[v3,1/3] thermal: sun8i: add thermal driver for h6

Commit Message

Yangtao Li May 25, 2019, 6:13 p.m. UTC

This patch adds the support for allwinner thermal sensor, within
allwinner SoC. It will register sensors for thermal framework
and use device tree to bind cooling device.

Signed-off-by: Yangtao Li <[e-mail]>
---
 MAINTAINERS                     |   7 +
 drivers/thermal/Kconfig         |  14 +
 drivers/thermal/Makefile        |   1 +
 drivers/thermal/sun8i_thermal.c | 437 ++++++++++++++++++++++++++++++++
 4 files changed, 459 insertions(+)
 create mode 100644 drivers/thermal/sun8i_thermal.c

Comments

Maxime Ripard May 27, 2019, 12:27 p.m. UTC | #1

Hi!

Thanks for submitting a new version

On Sat, May 25, 2019 at 02:13:27PM -0400, Yangtao Li wrote:
> This patch adds the support for allwinner thermal sensor, within
> allwinner SoC. It will register sensors for thermal framework
> and use device tree to bind cooling device.
>
> Signed-off-by: Yangtao Li <[e-mail]>
> ---
>  MAINTAINERS                     |   7 +
>  drivers/thermal/Kconfig         |  14 +
>  drivers/thermal/Makefile        |   1 +
>  drivers/thermal/sun8i_thermal.c | 437 ++++++++++++++++++++++++++++++++
>  4 files changed, 459 insertions(+)
>  create mode 100644 drivers/thermal/sun8i_thermal.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 2336dd26ece4..d312f9eecf0d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -674,6 +674,13 @@ L:	[e-mail]
>  S:	Maintained
>  F:	drivers/crypto/sunxi-ss/
>
> +ALLWINNER THERMAL DRIVER
> +M:	Yangtao Li <[e-mail]>
> +L:	[e-mail]
> +S:	Maintained
> +F:	Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
> +F:	drivers/thermal/sun8i_thermal.c
> +
>  ALLWINNER VPU DRIVER
>  M:	Maxime Ripard <[e-mail]>
>  M:	Paul Kocialkowski <[e-mail]>
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index 9966364a6deb..e5465053d66f 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -262,6 +262,20 @@ config SPEAR_THERMAL
>  	  Enable this to plug the SPEAr thermal sensor driver into the Linux
>  	  thermal framework.
>
> +config SUN8I_THERMAL
> +	tristate "Allwinner sun8i thermal driver"
> +	depends on ARCH_SUNXI || COMPILE_TEST
> +	depends on HAS_IOMEM
> +	depends on NVMEM_SUNXI_SID

Do you? It looks from your binding as if it's optional. Also, it's
pretty uncommon to depend on a given driver, usually you'll want to
depend on the framework instead.

> +	depends on OF
> +	depends on RESET_CONTROLLER
> +	help
> +	  Support for the sun8i thermal sensor driver into the Linux thermal
> +	  framework.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called sun8i-thermal.
> +
>  config ROCKCHIP_THERMAL
>  	tristate "Rockchip thermal driver"
>  	depends on ARCH_ROCKCHIP || COMPILE_TEST
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index 74a37c7f847a..fa6f8b206281 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -31,6 +31,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
>  obj-y				+= broadcom/
>  obj-$(CONFIG_THERMAL_MMIO)		+= thermal_mmio.o
>  obj-$(CONFIG_SPEAR_THERMAL)	+= spear_thermal.o
> +obj-$(CONFIG_SUN8I_THERMAL)     += sun8i_thermal.o
>  obj-$(CONFIG_ROCKCHIP_THERMAL)	+= rockchip_thermal.o
>  obj-$(CONFIG_RCAR_THERMAL)	+= rcar_thermal.o
>  obj-$(CONFIG_RCAR_GEN3_THERMAL)	+= rcar_gen3_thermal.o
> diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
> new file mode 100644
> index 000000000000..a9cc2197f4cb
> --- /dev/null
> +++ b/drivers/thermal/sun8i_thermal.c
> @@ -0,0 +1,437 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Thermal sensor driver for Allwinner SOC
> + * Copyright (C) 2019 Yangtao Li
> + *
> + * Based on the work of Icenowy Zheng <[e-mail]>
> + * Based on the work of Ondrej Jirman <[e-mail]>
> + * Based on the work of Josef Gajdusek <[e-mail]>
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/device.h>
> +#include <linux/interrupt.h>
> +#include <linux/wait.h>
> +#include <linux/module.h>
> +#include <linux/nvmem-consumer.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include <linux/slab.h>
> +#include <linux/thermal.h>
> +
> +#define MAX_SENSOR_NUM	4
> +
> +#define FT_TEMP_MASK				GENMASK(11, 0)
> +#define TEMP_CALIB_MASK				GENMASK(11, 0)
> +#define TEMP_TO_REG				672
> +#define CALIBRATE_DEFAULT			0x800
> +
> +#define SUN50I_THS_CTRL0			0x00
> +#define SUN50I_H6_THS_ENABLE			0x04
> +#define SUN50I_H6_THS_PC			0x08
> +#define SUN50I_H6_THS_DIC			0x10
> +#define SUN50I_H6_THS_DIS			0x20
> +#define SUN50I_H6_THS_MFC			0x30
> +#define SUN50I_H6_THS_TEMP_CALIB		0xa0
> +#define SUN50I_H6_THS_TEMP_DATA			0xc0
> +
> +#define SUN50I_THS_CTRL0_T_ACQ(x)		((GENMASK(15, 0) & (x)) << 16)
> +#define SUN50I_THS_FILTER_EN			BIT(2)
> +#define SUN50I_THS_FILTER_TYPE(x)		(GENMASK(1, 0) & (x))
> +#define SUN50I_H6_THS_PC_TEMP_PERIOD(x)		((GENMASK(19, 0) & (x)) << 12)
> +#define SUN50I_H6_THS_DATA_IRQ_STS(x)		BIT(x)
> +
> +/* millidegree celsius */
> +#define SUN50I_H6_FT_DEVIATION			7000
> +
> +struct ths_device;
> +
> +struct tsensor {
> +	struct ths_device		*tmdev;
> +	struct thermal_zone_device	*tzd;
> +	int				id;
> +	wait_queue_head_t		wait_queue;
> +};
> +
> +struct ths_thermal_chip {
> +	int		sensor_num;
> +	int		offset;
> +	int		scale;
> +	int		ft_deviation;
> +	int		temp_calib_base;
> +	int		temp_data_base;
> +	int		(*calibrate)(struct ths_device *tmdev);
> +	int		(*init)(struct ths_device *tmdev);
> +	irqreturn_t	(*irq_thread)(int irq, void *data);
> +};

Again, you should remove these quirks structure at the moment and only
deal with the H6.

> +struct ths_device {
> +	const struct ths_thermal_chip		*chip;
> +	struct device				*dev;
> +	struct regmap				*regmap;
> +	struct reset_control			*reset;
> +	struct clk				*bus_clk;
> +	struct tsensor				sensor[MAX_SENSOR_NUM];
> +	int					data_ready;
> +};
> +
> +/* Temp Unit: millidegree Celsius */
> +static int sun8i_ths_reg2temp(struct ths_device *tmdev,
> +			      int reg)
> +{
> +	return (reg + tmdev->chip->offset) * tmdev->chip->scale;
> +}
> +
> +static int sun8i_ths_get_temp(void *data, int *temp)
> +{
> +	struct tsensor *s = data;
> +	struct ths_device *tmdev = s->tmdev;
> +	int val;
> +
> +	wait_event(s->wait_queue, tmdev->data_ready & BIT(s->id));
> +	tmdev->data_ready &= ~BIT(s->id);
> +
> +	regmap_read(tmdev->regmap, tmdev->chip->temp_data_base +
> +		    0x4 * s->id, &val);
> +
> +	*temp = sun8i_ths_reg2temp(tmdev, val);
> +	/*
> +	 * XX - According to the original sdk, there are some platforms(rarely)
> +	 * that add a fixed offset value after calculating the temperature
> +	 * value. We can't simply put it on the formula for calculating the
> +	 * temperature above, because the formula for calculating the
> +	 * temperature above is also used when the sensor is calibrated. If
> +	 * do this, the correct calibration formula is hard to know.
> +	 */
> +	if (tmdev->chip->ft_deviation)
> +		*temp += tmdev->chip->ft_deviation;
> +
> +	return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops ths_ops = {
> +	.get_temp = sun8i_ths_get_temp,
> +};
> +
> +static const struct regmap_config config = {
> +	.reg_bits = 32,
> +	.val_bits = 32,
> +	.reg_stride = 4,
> +	.fast_io = true,
> +};
> +
> +static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
> +{
> +	wait_queue_head_t *data_wait;
> +	struct ths_device *tmdev = data;
> +	int i, state;
> +
> +	regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
> +
> +	for (i = 0; i < tmdev->chip->sensor_num; i++) {
> +		data_wait = &tmdev->sensor[i].wait_queue;

You're only using data_wait in that scope, so you should define it
here.

> +
> +		if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
> +			/* clear data irq pending */
> +			regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
> +				     SUN50I_H6_THS_DATA_IRQ_STS(i));
> +
> +			tmdev->data_ready |= BIT(i);
> +			wake_up(data_wait);
> +		}
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int sun8i_ths_resource_init(struct ths_device *tmdev)
> +{
> +	struct device *dev = tmdev->dev;
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct resource *mem;
> +	void __iomem *base;
> +	int ret, irq;
> +
> +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	base = devm_ioremap_resource(dev, mem);
> +	if (IS_ERR(base))
> +		return PTR_ERR(base);
> +
> +	tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
> +	if (IS_ERR(tmdev->regmap))
> +		return PTR_ERR(tmdev->regmap);
> +
> +	tmdev->reset = devm_reset_control_get(dev, 0);
> +	if (IS_ERR(tmdev->reset))
> +		return PTR_ERR(tmdev->reset);
> +
> +	tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
> +	if (IS_ERR(tmdev->bus_clk))
> +		return PTR_ERR(tmdev->bus_clk);
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return irq;
> +
> +	ret = devm_request_threaded_irq(dev, irq, NULL,
> +					tmdev->chip->irq_thread,
> +					IRQF_ONESHOT, "ths", tmdev);
> +	if (ret)
> +		return ret;

Is there any particular reason to use a threaded interrupt?

Also, starting from here you can start having interrupts...

> +
> +	ret = reset_control_deassert(tmdev->reset);
> +	if (ret)
> +		return ret;
> +
> +	ret = clk_prepare_enable(tmdev->bus_clk);
> +	if (ret)
> +		goto assert_reset;
> +
> +	ret = tmdev->chip->calibrate(tmdev);
> +	if (ret)
> +		goto bus_disable;

While the device hasn't been properly initialized yet. Especially when
held in reset, some Allwinner controllers has been known to send
spurious interrupts, so we want to defer that to the very last minute
(so right before your call to sun8i_ths_register).

> +	return 0;
> +
> +bus_disable:
> +	clk_disable_unprepare(tmdev->bus_clk);
> +assert_reset:
> +	reset_control_assert(tmdev->reset);
> +
> +	return ret;
> +}
> +
> +static int sun50i_ths_calibrate(struct ths_device *tmdev)
> +{
> +	struct nvmem_cell *calcell;
> +	struct device *dev = tmdev->dev;
> +	u16 *caldata;
> +	size_t callen;
> +	int ft_temp;
> +	int i, ret = 0;
> +
> +	calcell = devm_nvmem_cell_get(dev, "calib");
> +	if (IS_ERR(calcell)) {
> +		if (PTR_ERR(calcell) == -EPROBE_DEFER)
> +			return -EPROBE_DEFER;
> +		/*
> +		 * Even if the external calibration data stored in sid is
> +		 * not accessible, the THS hardware can still work, although
> +		 * the data won't be so accurate.
> +		 *
> +		 * The default value of calibration register is 0x800 for
> +		 * every sensor, and the calibration value is usually 0x7xx
> +		 * or 0x8xx, so they won't be away from the default value
> +		 * for a lot.
> +		 *
> +		 * So here we do not return error if the calibartion data is
> +		 * not available, except the probe needs deferring.
> +		 */
> +		goto out;
> +	}
> +
> +	caldata = nvmem_cell_read(calcell, &callen);
> +	if (IS_ERR(caldata)) {
> +		ret = PTR_ERR(caldata);
> +		goto out;
> +	}
> +
> +	if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) {
> +		ret = -EINVAL;
> +		goto out_free;
> +	}
> +
> +	/*
> +	 * efuse layout:
> +	 *
> +	 *	0   11  16	 32
> +	 *	+-------+-------+-------+
> +	 *	|temp|  |sensor0|sensor1|
> +	 *	+-------+-------+-------+
> +	 *
> +	 * The calibration data on the H6 is the ambient temperature and
> +	 * sensor values that are filled during the factory test stage.
> +	 *
> +	 * The unit of stored FT temperature is 0.1 degreee celusis.
> +	 * Through the stored ambient temperature and the data read
> +	 * by the sensor, after a certain calculation, the calibration
> +	 * value to be compensated can be obtained.
> +	 */
> +	ft_temp = caldata[0] & FT_TEMP_MASK;
> +
> +	for (i = 0; i < tmdev->chip->sensor_num; i++) {
> +		int reg = (int)caldata[i + 1];
> +		int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
> +		int delta, cdata, calib_offest;
> +
> +		/*
> +		 * To calculate the calibration value:
> +		 *
> +		 * X(in Celsius) = Ts - ft_temp
> +		 * delta = X * 10000 / TEMP_TO_REG
> +		 * cdata = CALIBRATE_DEFAULT - delta
> +		 *
> +		 * cdata: calibration value
> +		 */
> +		delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
> +		cdata = CALIBRATE_DEFAULT - delta;
> +		if (cdata & ~TEMP_CALIB_MASK) {
> +			/*
> +			 * Calibration value more than 12-bit, but calibration
> +			 * register is 12-bit. In this case, ths hardware can
> +			 * still work without calibration, although the data
> +			 * won't be so accurate.
> +			 */
> +			dev_warn(dev, "sensor%d is not calibrated.\n", i);
> +
> +			continue;
> +		}
> +
> +		calib_offest = tmdev->chip->temp_calib_base + (i / 2) * 0x4;
> +
> +		if (i % 2) {
> +			int val;
> +
> +			regmap_read(tmdev->regmap, calib_offest, &val);
> +			val = (val & TEMP_CALIB_MASK) | (cdata << 16);
> +			regmap_write(tmdev->regmap, calib_offest, val);
> +		} else {
> +			regmap_write(tmdev->regmap, calib_offest, cdata);
> +		}
> +	}
> +
> +out_free:
> +	kfree(caldata);
> +out:
> +	return ret;
> +}
> +
> +static int sun8i_ths_register(struct ths_device *tmdev)
> +{
> +	struct thermal_zone_device *tzd;
> +	int i;
> +
> +	for (i = 0; i < tmdev->chip->sensor_num; i++) {
> +		tmdev->sensor[i].tmdev = tmdev;
> +		tmdev->sensor[i].id = i;
> +		tmdev->sensor[i].tzd =
> +			devm_thermal_zone_of_sensor_register(tmdev->dev,
> +							     i,
> +							     &tmdev->sensor[i],
> +							     &ths_ops);
> +		if (IS_ERR(tmdev->sensor[i].tzd))
> +			return PTR_ERR(tzd);
> +	}
> +
> +	return 0;
> +}
> +
> +static int sun8i_ths_probe(struct platform_device *pdev)
> +{
> +	struct ths_device *tmdev;
> +	struct device *dev = &pdev->dev;
> +	int i, ret;
> +
> +	tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
> +	if (!tmdev)
> +		return -ENOMEM;
> +
> +	tmdev->dev = dev;
> +	tmdev->chip = of_device_get_match_data(&pdev->dev);
> +	if (!tmdev->chip)
> +		return -EINVAL;
> +
> +	/*
> +	 * Initialize wait_queue in advance, to avoid calling wake_up
> +	 * before ths is registered in isr.
> +	 */
> +	for (i = 0; i < tmdev->chip->sensor_num; i++)
> +		init_waitqueue_head(&tmdev->sensor[i].wait_queue);
> +
> +	platform_set_drvdata(pdev, tmdev);
> +
> +	ret = sun8i_ths_resource_init(tmdev);
> +	if (ret)
> +		return ret;
> +
> +	ret = tmdev->chip->init(tmdev);
> +	if (ret)
> +		return ret;
> +
> +	ret = sun8i_ths_register(tmdev);
> +	if (ret)
> +		return ret;
> +
> +	return ret;
> +}
> +
> +static int sun8i_ths_remove(struct platform_device *pdev)
> +{
> +	struct ths_device *tmdev = platform_get_drvdata(pdev);
> +
> +	clk_disable_unprepare(tmdev->bus_clk);

I know that we discussed that already, but I'm not sure why you switch
back to a regular call to regmap_init_mmio, while regmap_init_mmio_clk
will take care of enabling and disabling the bus clock for you?

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Ondřej Jirman May 27, 2019, 2:25 p.m. UTC | #2

Hi Yangtao,

On Sat, May 25, 2019 at 02:13:27PM -0400, Yangtao Li wrote:
> This patch adds the support for allwinner thermal sensor, within
> allwinner SoC. It will register sensors for thermal framework
> and use device tree to bind cooling device.
> 
> Signed-off-by: Yangtao Li <[e-mail]>
> ---
>  MAINTAINERS                     |   7 +
>  drivers/thermal/Kconfig         |  14 +
>  drivers/thermal/Makefile        |   1 +
>  drivers/thermal/sun8i_thermal.c | 437 ++++++++++++++++++++++++++++++++
>  4 files changed, 459 insertions(+)
>  create mode 100644 drivers/thermal/sun8i_thermal.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 2336dd26ece4..d312f9eecf0d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -674,6 +674,13 @@ L:	[e-mail]
>  S:	Maintained
>  F:	drivers/crypto/sunxi-ss/
>  
> +ALLWINNER THERMAL DRIVER
> +M:	Yangtao Li <[e-mail]>
> +L:	[e-mail]
> +S:	Maintained
> +F:	Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
> +F:	drivers/thermal/sun8i_thermal.c
> +
>  ALLWINNER VPU DRIVER
>  M:	Maxime Ripard <[e-mail]>
>  M:	Paul Kocialkowski <[e-mail]>
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index 9966364a6deb..e5465053d66f 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -262,6 +262,20 @@ config SPEAR_THERMAL
>  	  Enable this to plug the SPEAr thermal sensor driver into the Linux
>  	  thermal framework.
>  
> +config SUN8I_THERMAL
> +	tristate "Allwinner sun8i thermal driver"
> +	depends on ARCH_SUNXI || COMPILE_TEST
> +	depends on HAS_IOMEM
> +	depends on NVMEM_SUNXI_SID
> +	depends on OF
> +	depends on RESET_CONTROLLER
> +	help
> +	  Support for the sun8i thermal sensor driver into the Linux thermal
> +	  framework.
> +
> +	  To compile this driver as a module, choose M here: the
> +	  module will be called sun8i-thermal.
> +
>  config ROCKCHIP_THERMAL
>  	tristate "Rockchip thermal driver"
>  	depends on ARCH_ROCKCHIP || COMPILE_TEST
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index 74a37c7f847a..fa6f8b206281 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -31,6 +31,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
>  obj-y				+= broadcom/
>  obj-$(CONFIG_THERMAL_MMIO)		+= thermal_mmio.o
>  obj-$(CONFIG_SPEAR_THERMAL)	+= spear_thermal.o
> +obj-$(CONFIG_SUN8I_THERMAL)     += sun8i_thermal.o
>  obj-$(CONFIG_ROCKCHIP_THERMAL)	+= rockchip_thermal.o
>  obj-$(CONFIG_RCAR_THERMAL)	+= rcar_thermal.o
>  obj-$(CONFIG_RCAR_GEN3_THERMAL)	+= rcar_gen3_thermal.o
> diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
> new file mode 100644
> index 000000000000..a9cc2197f4cb
> --- /dev/null
> +++ b/drivers/thermal/sun8i_thermal.c
> @@ -0,0 +1,437 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Thermal sensor driver for Allwinner SOC
> + * Copyright (C) 2019 Yangtao Li
> + *
> + * Based on the work of Icenowy Zheng <[e-mail]>
> + * Based on the work of Ondrej Jirman <[e-mail]>
> + * Based on the work of Josef Gajdusek <[e-mail]>
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/device.h>
> +#include <linux/interrupt.h>
> +#include <linux/wait.h>
> +#include <linux/module.h>
> +#include <linux/nvmem-consumer.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include <linux/slab.h>
> +#include <linux/thermal.h>
> +
> +#define MAX_SENSOR_NUM	4
> +
> +#define FT_TEMP_MASK				GENMASK(11, 0)
> +#define TEMP_CALIB_MASK				GENMASK(11, 0)
> +#define TEMP_TO_REG				672
> +#define CALIBRATE_DEFAULT			0x800
> +
> +#define SUN50I_THS_CTRL0			0x00
> +#define SUN50I_H6_THS_ENABLE			0x04
> +#define SUN50I_H6_THS_PC			0x08
> +#define SUN50I_H6_THS_DIC			0x10
> +#define SUN50I_H6_THS_DIS			0x20
> +#define SUN50I_H6_THS_MFC			0x30
> +#define SUN50I_H6_THS_TEMP_CALIB		0xa0
> +#define SUN50I_H6_THS_TEMP_DATA			0xc0
> +
> +#define SUN50I_THS_CTRL0_T_ACQ(x)		((GENMASK(15, 0) & (x)) << 16)
> +#define SUN50I_THS_FILTER_EN			BIT(2)
> +#define SUN50I_THS_FILTER_TYPE(x)		(GENMASK(1, 0) & (x))
> +#define SUN50I_H6_THS_PC_TEMP_PERIOD(x)		((GENMASK(19, 0) & (x)) << 12)
> +#define SUN50I_H6_THS_DATA_IRQ_STS(x)		BIT(x)
> +
> +/* millidegree celsius */
> +#define SUN50I_H6_FT_DEVIATION			7000
> +
> +struct ths_device;
> +
> +struct tsensor {
> +	struct ths_device		*tmdev;
> +	struct thermal_zone_device	*tzd;
> +	int				id;
> +	wait_queue_head_t		wait_queue;
> +};
> +
> +struct ths_thermal_chip {
> +	int		sensor_num;
> +	int		offset;
> +	int		scale;
> +	int		ft_deviation;
> +	int		temp_calib_base;
> +	int		temp_data_base;
> +	int		(*calibrate)(struct ths_device *tmdev);
> +	int		(*init)(struct ths_device *tmdev);
> +	irqreturn_t	(*irq_thread)(int irq, void *data);
> +};
> +
> +struct ths_device {
> +	const struct ths_thermal_chip		*chip;
> +	struct device				*dev;
> +	struct regmap				*regmap;
> +	struct reset_control			*reset;
> +	struct clk				*bus_clk;
> +	struct tsensor				sensor[MAX_SENSOR_NUM];
> +	int					data_ready;
> +};
> +
> +/* Temp Unit: millidegree Celsius */
> +static int sun8i_ths_reg2temp(struct ths_device *tmdev,
> +			      int reg)
> +{
> +	return (reg + tmdev->chip->offset) * tmdev->chip->scale;
> +}
> +
> +static int sun8i_ths_get_temp(void *data, int *temp)
> +{
> +	struct tsensor *s = data;
> +	struct ths_device *tmdev = s->tmdev;
> +	int val;
> +
> +	wait_event(s->wait_queue, tmdev->data_ready & BIT(s->id));
> +	tmdev->data_ready &= ~BIT(s->id);

I've looked at thermal_core.c and it looks like that the proper way to handle
this situation is just returning -EAGAIN.

See update_temperature() function in thermal_core.c.

That will suppress the warning about failure to read thermal zone. Also
it's much simpler than this wait_queue stuff. No other thermal driver uses this
either. Also get_temp is called under thermal_list_lock mutex and that would
block cooling device registrations and god knows what else.

Other than that, and what Maxime said, I don't see any more issues.

thank you,
	o.

> +	regmap_read(tmdev->regmap, tmdev->chip->temp_data_base +
> +		    0x4 * s->id, &val);
> +
> +	*temp = sun8i_ths_reg2temp(tmdev, val);
> +	/*
> +	 * XX - According to the original sdk, there are some platforms(rarely)
> +	 * that add a fixed offset value after calculating the temperature
> +	 * value. We can't simply put it on the formula for calculating the
> +	 * temperature above, because the formula for calculating the
> +	 * temperature above is also used when the sensor is calibrated. If
> +	 * do this, the correct calibration formula is hard to know.
> +	 */
> +	if (tmdev->chip->ft_deviation)
> +		*temp += tmdev->chip->ft_deviation;
> +
> +	return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops ths_ops = {
> +	.get_temp = sun8i_ths_get_temp,
> +};
> +
> +static const struct regmap_config config = {
> +	.reg_bits = 32,
> +	.val_bits = 32,
> +	.reg_stride = 4,
> +	.fast_io = true,
> +};
> +
> +static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
> +{
> +	wait_queue_head_t *data_wait;
> +	struct ths_device *tmdev = data;
> +	int i, state;
> +
> +	regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
> +
> +	for (i = 0; i < tmdev->chip->sensor_num; i++) {
> +		data_wait = &tmdev->sensor[i].wait_queue;
> +
> +		if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
> +			/* clear data irq pending */
> +			regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
> +				     SUN50I_H6_THS_DATA_IRQ_STS(i));
> +
> +			tmdev->data_ready |= BIT(i);
> +			wake_up(data_wait);
> +		}
> +	}
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static int sun8i_ths_resource_init(struct ths_device *tmdev)
> +{
> +	struct device *dev = tmdev->dev;
> +	struct platform_device *pdev = to_platform_device(dev);
> +	struct resource *mem;
> +	void __iomem *base;
> +	int ret, irq;
> +
> +	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +	base = devm_ioremap_resource(dev, mem);
> +	if (IS_ERR(base))
> +		return PTR_ERR(base);
> +
> +	tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
> +	if (IS_ERR(tmdev->regmap))
> +		return PTR_ERR(tmdev->regmap);
> +
> +	tmdev->reset = devm_reset_control_get(dev, 0);
> +	if (IS_ERR(tmdev->reset))
> +		return PTR_ERR(tmdev->reset);
> +
> +	tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
> +	if (IS_ERR(tmdev->bus_clk))
> +		return PTR_ERR(tmdev->bus_clk);
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0)
> +		return irq;
> +
> +	ret = devm_request_threaded_irq(dev, irq, NULL,
> +					tmdev->chip->irq_thread,
> +					IRQF_ONESHOT, "ths", tmdev);
> +	if (ret)
> +		return ret;
> +
> +	ret = reset_control_deassert(tmdev->reset);
> +	if (ret)
> +		return ret;
> +
> +	ret = clk_prepare_enable(tmdev->bus_clk);
> +	if (ret)
> +		goto assert_reset;
> +
> +	ret = tmdev->chip->calibrate(tmdev);
> +	if (ret)
> +		goto bus_disable;
> +
> +	return 0;
> +
> +bus_disable:
> +	clk_disable_unprepare(tmdev->bus_clk);
> +assert_reset:
> +	reset_control_assert(tmdev->reset);
> +
> +	return ret;
> +}
> +
> +static int sun50i_ths_calibrate(struct ths_device *tmdev)
> +{
> +	struct nvmem_cell *calcell;
> +	struct device *dev = tmdev->dev;
> +	u16 *caldata;
> +	size_t callen;
> +	int ft_temp;
> +	int i, ret = 0;
> +
> +	calcell = devm_nvmem_cell_get(dev, "calib");
> +	if (IS_ERR(calcell)) {
> +		if (PTR_ERR(calcell) == -EPROBE_DEFER)
> +			return -EPROBE_DEFER;
> +		/*
> +		 * Even if the external calibration data stored in sid is
> +		 * not accessible, the THS hardware can still work, although
> +		 * the data won't be so accurate.
> +		 *
> +		 * The default value of calibration register is 0x800 for
> +		 * every sensor, and the calibration value is usually 0x7xx
> +		 * or 0x8xx, so they won't be away from the default value
> +		 * for a lot.
> +		 *
> +		 * So here we do not return error if the calibartion data is
> +		 * not available, except the probe needs deferring.
> +		 */
> +		goto out;
> +	}
> +
> +	caldata = nvmem_cell_read(calcell, &callen);
> +	if (IS_ERR(caldata)) {
> +		ret = PTR_ERR(caldata);
> +		goto out;
> +	}
> +
> +	if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) {
> +		ret = -EINVAL;
> +		goto out_free;
> +	}
> +
> +	/*
> +	 * efuse layout:
> +	 *
> +	 *	0   11  16	 32
> +	 *	+-------+-------+-------+
> +	 *	|temp|  |sensor0|sensor1|
> +	 *	+-------+-------+-------+
> +	 *
> +	 * The calibration data on the H6 is the ambient temperature and
> +	 * sensor values that are filled during the factory test stage.
> +	 *
> +	 * The unit of stored FT temperature is 0.1 degreee celusis.
> +	 * Through the stored ambient temperature and the data read
> +	 * by the sensor, after a certain calculation, the calibration
> +	 * value to be compensated can be obtained.
> +	 */
> +	ft_temp = caldata[0] & FT_TEMP_MASK;
> +
> +	for (i = 0; i < tmdev->chip->sensor_num; i++) {
> +		int reg = (int)caldata[i + 1];
> +		int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
> +		int delta, cdata, calib_offest;
> +
> +		/*
> +		 * To calculate the calibration value:
> +		 *
> +		 * X(in Celsius) = Ts - ft_temp
> +		 * delta = X * 10000 / TEMP_TO_REG
> +		 * cdata = CALIBRATE_DEFAULT - delta
> +		 *
> +		 * cdata: calibration value
> +		 */
> +		delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
> +		cdata = CALIBRATE_DEFAULT - delta;
> +		if (cdata & ~TEMP_CALIB_MASK) {
> +			/*
> +			 * Calibration value more than 12-bit, but calibration
> +			 * register is 12-bit. In this case, ths hardware can
> +			 * still work without calibration, although the data
> +			 * won't be so accurate.
> +			 */
> +			dev_warn(dev, "sensor%d is not calibrated.\n", i);
> +
> +			continue;
> +		}
> +
> +		calib_offest = tmdev->chip->temp_calib_base + (i / 2) * 0x4;
> +
> +		if (i % 2) {
> +			int val;
> +
> +			regmap_read(tmdev->regmap, calib_offest, &val);
> +			val = (val & TEMP_CALIB_MASK) | (cdata << 16);
> +			regmap_write(tmdev->regmap, calib_offest, val);
> +		} else {
> +			regmap_write(tmdev->regmap, calib_offest, cdata);
> +		}
> +	}
> +
> +out_free:
> +	kfree(caldata);
> +out:
> +	return ret;
> +}
> +
> +static int sun8i_ths_register(struct ths_device *tmdev)
> +{
> +	struct thermal_zone_device *tzd;
> +	int i;
> +
> +	for (i = 0; i < tmdev->chip->sensor_num; i++) {
> +		tmdev->sensor[i].tmdev = tmdev;
> +		tmdev->sensor[i].id = i;
> +		tmdev->sensor[i].tzd =
> +			devm_thermal_zone_of_sensor_register(tmdev->dev,
> +							     i,
> +							     &tmdev->sensor[i],
> +							     &ths_ops);
> +		if (IS_ERR(tmdev->sensor[i].tzd))
> +			return PTR_ERR(tzd);
> +	}
> +
> +	return 0;
> +}
> +
> +static int sun8i_ths_probe(struct platform_device *pdev)
> +{
> +	struct ths_device *tmdev;
> +	struct device *dev = &pdev->dev;
> +	int i, ret;
> +
> +	tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
> +	if (!tmdev)
> +		return -ENOMEM;
> +
> +	tmdev->dev = dev;
> +	tmdev->chip = of_device_get_match_data(&pdev->dev);
> +	if (!tmdev->chip)
> +		return -EINVAL;
> +
> +	/*
> +	 * Initialize wait_queue in advance, to avoid calling wake_up
> +	 * before ths is registered in isr.
> +	 */
> +	for (i = 0; i < tmdev->chip->sensor_num; i++)
> +		init_waitqueue_head(&tmdev->sensor[i].wait_queue);
> +
> +	platform_set_drvdata(pdev, tmdev);
> +
> +	ret = sun8i_ths_resource_init(tmdev);
> +	if (ret)
> +		return ret;
> +
> +	ret = tmdev->chip->init(tmdev);
> +	if (ret)
> +		return ret;
> +
> +	ret = sun8i_ths_register(tmdev);
> +	if (ret)
> +		return ret;
> +
> +	return ret;
> +}
> +
> +static int sun8i_ths_remove(struct platform_device *pdev)
> +{
> +	struct ths_device *tmdev = platform_get_drvdata(pdev);
> +
> +	clk_disable_unprepare(tmdev->bus_clk);
> +	reset_control_assert(tmdev->reset);
> +
> +	return 0;
> +}
> +
> +static int sun50i_thermal_init(struct ths_device *tmdev)
> +{
> +	int val;
> +
> +	/*
> +	 * clkin = 24MHz
> +	 * T acquire = clkin / (x + 1)
> +	 *           = 20us
> +	 */
> +	regmap_write(tmdev->regmap, SUN50I_THS_CTRL0,
> +		     SUN50I_THS_CTRL0_T_ACQ(479));
> +	/* average over 4 samples */
> +	regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC,
> +		     SUN50I_THS_FILTER_EN |
> +		     SUN50I_THS_FILTER_TYPE(1));
> +	/* period = (x + 1) * 4096 / clkin; ~10ms */
> +	regmap_write(tmdev->regmap, SUN50I_H6_THS_PC,
> +		     SUN50I_H6_THS_PC_TEMP_PERIOD(58));
> +	/* enable sensor */
> +	val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> +	regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val);
> +	/* thermal data interrupt enable */
> +	val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> +	regmap_write(tmdev->regmap, SUN50I_H6_THS_DIC, val);
> +
> +	return 0;
> +}
> +
> +static const struct ths_thermal_chip sun50i_h6_ths = {
> +	.sensor_num = 2,
> +	.offset = -2794,
> +	.scale = -67,
> +	.ft_deviation = SUN50I_H6_FT_DEVIATION,
> +	.temp_calib_base = SUN50I_H6_THS_TEMP_CALIB,
> +	.temp_data_base = SUN50I_H6_THS_TEMP_DATA,
> +	.calibrate = sun50i_ths_calibrate,
> +	.init = sun50i_thermal_init,
> +	.irq_thread = sun50i_h6_irq_thread,
> +};
> +
> +static const struct of_device_id of_ths_match[] = {
> +	{ .compatible = "allwinner,sun50i-h6-ths", .data = &sun50i_h6_ths },
> +	{ /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, of_ths_match);
> +
> +static struct platform_driver ths_driver = {
> +	.probe = sun8i_ths_probe,
> +	.remove = sun8i_ths_remove,
> +	.driver = {
> +		.name = "sun8i-thermal",
> +		.of_match_table = of_ths_match,
> +	},
> +};
> +module_platform_driver(ths_driver);
> +
> +MODULE_DESCRIPTION("Thermal sensor driver for Allwinner SOC");
> +MODULE_LICENSE("GPL v2");
> -- 
> 2.17.0
> 
> 
> _______________________________________________
> linux-arm-kernel mailing list
> [e-mail]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Yangtao Li June 7, 2019, 1:34 p.m. UTC | #3

On Mon, May 27, 2019 at 8:27 PM Maxime Ripard <[e-mail]> wrote:
>
> Hi!
>
> Thanks for submitting a new version
>
> On Sat, May 25, 2019 at 02:13:27PM -0400, Yangtao Li wrote:
> > This patch adds the support for allwinner thermal sensor, within
> > allwinner SoC. It will register sensors for thermal framework
> > and use device tree to bind cooling device.
> >
> > Signed-off-by: Yangtao Li <[e-mail]>
> > ---
> >  MAINTAINERS                     |   7 +
> >  drivers/thermal/Kconfig         |  14 +
> >  drivers/thermal/Makefile        |   1 +
> >  drivers/thermal/sun8i_thermal.c | 437 ++++++++++++++++++++++++++++++++
> >  4 files changed, 459 insertions(+)
> >  create mode 100644 drivers/thermal/sun8i_thermal.c
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 2336dd26ece4..d312f9eecf0d 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -674,6 +674,13 @@ L:       [e-mail]
> >  S:   Maintained
> >  F:   drivers/crypto/sunxi-ss/
> >
> > +ALLWINNER THERMAL DRIVER
> > +M:   Yangtao Li <[e-mail]>
> > +L:   [e-mail]
> > +S:   Maintained
> > +F:   Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
> > +F:   drivers/thermal/sun8i_thermal.c
> > +
> >  ALLWINNER VPU DRIVER
> >  M:   Maxime Ripard <[e-mail]>
> >  M:   Paul Kocialkowski <[e-mail]>
> > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> > index 9966364a6deb..e5465053d66f 100644
> > --- a/drivers/thermal/Kconfig
> > +++ b/drivers/thermal/Kconfig
> > @@ -262,6 +262,20 @@ config SPEAR_THERMAL
> >         Enable this to plug the SPEAr thermal sensor driver into the Linux
> >         thermal framework.
> >
> > +config SUN8I_THERMAL
> > +     tristate "Allwinner sun8i thermal driver"
> > +     depends on ARCH_SUNXI || COMPILE_TEST
> > +     depends on HAS_IOMEM
> > +     depends on NVMEM_SUNXI_SID
>
> Do you? It looks from your binding as if it's optional. Also, it's
> pretty uncommon to depend on a given driver, usually you'll want to
> depend on the framework instead.
>
> > +     depends on OF
> > +     depends on RESET_CONTROLLER
> > +     help
> > +       Support for the sun8i thermal sensor driver into the Linux thermal
> > +       framework.
> > +
> > +       To compile this driver as a module, choose M here: the
> > +       module will be called sun8i-thermal.
> > +
> >  config ROCKCHIP_THERMAL
> >       tristate "Rockchip thermal driver"
> >       depends on ARCH_ROCKCHIP || COMPILE_TEST
> > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> > index 74a37c7f847a..fa6f8b206281 100644
> > --- a/drivers/thermal/Makefile
> > +++ b/drivers/thermal/Makefile
> > @@ -31,6 +31,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
> >  obj-y                                += broadcom/
> >  obj-$(CONFIG_THERMAL_MMIO)           += thermal_mmio.o
> >  obj-$(CONFIG_SPEAR_THERMAL)  += spear_thermal.o
> > +obj-$(CONFIG_SUN8I_THERMAL)     += sun8i_thermal.o
> >  obj-$(CONFIG_ROCKCHIP_THERMAL)       += rockchip_thermal.o
> >  obj-$(CONFIG_RCAR_THERMAL)   += rcar_thermal.o
> >  obj-$(CONFIG_RCAR_GEN3_THERMAL)      += rcar_gen3_thermal.o
> > diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
> > new file mode 100644
> > index 000000000000..a9cc2197f4cb
> > --- /dev/null
> > +++ b/drivers/thermal/sun8i_thermal.c
> > @@ -0,0 +1,437 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Thermal sensor driver for Allwinner SOC
> > + * Copyright (C) 2019 Yangtao Li
> > + *
> > + * Based on the work of Icenowy Zheng <[e-mail]>
> > + * Based on the work of Ondrej Jirman <[e-mail]>
> > + * Based on the work of Josef Gajdusek <[e-mail]>
> > + */
> > +
> > +#include <linux/clk.h>
> > +#include <linux/device.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/wait.h>
> > +#include <linux/module.h>
> > +#include <linux/nvmem-consumer.h>
> > +#include <linux/of_device.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/regmap.h>
> > +#include <linux/reset.h>
> > +#include <linux/slab.h>
> > +#include <linux/thermal.h>
> > +
> > +#define MAX_SENSOR_NUM       4
> > +
> > +#define FT_TEMP_MASK                         GENMASK(11, 0)
> > +#define TEMP_CALIB_MASK                              GENMASK(11, 0)
> > +#define TEMP_TO_REG                          672
> > +#define CALIBRATE_DEFAULT                    0x800
> > +
> > +#define SUN50I_THS_CTRL0                     0x00
> > +#define SUN50I_H6_THS_ENABLE                 0x04
> > +#define SUN50I_H6_THS_PC                     0x08
> > +#define SUN50I_H6_THS_DIC                    0x10
> > +#define SUN50I_H6_THS_DIS                    0x20
> > +#define SUN50I_H6_THS_MFC                    0x30
> > +#define SUN50I_H6_THS_TEMP_CALIB             0xa0
> > +#define SUN50I_H6_THS_TEMP_DATA                      0xc0
> > +
> > +#define SUN50I_THS_CTRL0_T_ACQ(x)            ((GENMASK(15, 0) & (x)) << 16)
> > +#define SUN50I_THS_FILTER_EN                 BIT(2)
> > +#define SUN50I_THS_FILTER_TYPE(x)            (GENMASK(1, 0) & (x))
> > +#define SUN50I_H6_THS_PC_TEMP_PERIOD(x)              ((GENMASK(19, 0) & (x)) << 12)
> > +#define SUN50I_H6_THS_DATA_IRQ_STS(x)                BIT(x)
> > +
> > +/* millidegree celsius */
> > +#define SUN50I_H6_FT_DEVIATION                       7000
> > +
> > +struct ths_device;
> > +
> > +struct tsensor {
> > +     struct ths_device               *tmdev;
> > +     struct thermal_zone_device      *tzd;
> > +     int                             id;
> > +     wait_queue_head_t               wait_queue;
> > +};
> > +
> > +struct ths_thermal_chip {
> > +     int             sensor_num;
> > +     int             offset;
> > +     int             scale;
> > +     int             ft_deviation;
> > +     int             temp_calib_base;
> > +     int             temp_data_base;
> > +     int             (*calibrate)(struct ths_device *tmdev);
> > +     int             (*init)(struct ths_device *tmdev);
> > +     irqreturn_t     (*irq_thread)(int irq, void *data);
> > +};
>
> Again, you should remove these quirks structure at the moment and only
> deal with the H6.
>
> > +struct ths_device {
> > +     const struct ths_thermal_chip           *chip;
> > +     struct device                           *dev;
> > +     struct regmap                           *regmap;
> > +     struct reset_control                    *reset;
> > +     struct clk                              *bus_clk;
> > +     struct tsensor                          sensor[MAX_SENSOR_NUM];
> > +     int                                     data_ready;
> > +};
> > +
> > +/* Temp Unit: millidegree Celsius */
> > +static int sun8i_ths_reg2temp(struct ths_device *tmdev,
> > +                           int reg)
> > +{
> > +     return (reg + tmdev->chip->offset) * tmdev->chip->scale;
> > +}
> > +
> > +static int sun8i_ths_get_temp(void *data, int *temp)
> > +{
> > +     struct tsensor *s = data;
> > +     struct ths_device *tmdev = s->tmdev;
> > +     int val;
> > +
> > +     wait_event(s->wait_queue, tmdev->data_ready & BIT(s->id));
> > +     tmdev->data_ready &= ~BIT(s->id);
> > +
> > +     regmap_read(tmdev->regmap, tmdev->chip->temp_data_base +
> > +                 0x4 * s->id, &val);
> > +
> > +     *temp = sun8i_ths_reg2temp(tmdev, val);
> > +     /*
> > +      * XX - According to the original sdk, there are some platforms(rarely)
> > +      * that add a fixed offset value after calculating the temperature
> > +      * value. We can't simply put it on the formula for calculating the
> > +      * temperature above, because the formula for calculating the
> > +      * temperature above is also used when the sensor is calibrated. If
> > +      * do this, the correct calibration formula is hard to know.
> > +      */
> > +     if (tmdev->chip->ft_deviation)
> > +             *temp += tmdev->chip->ft_deviation;
> > +
> > +     return 0;
> > +}
> > +
> > +static const struct thermal_zone_of_device_ops ths_ops = {
> > +     .get_temp = sun8i_ths_get_temp,
> > +};
> > +
> > +static const struct regmap_config config = {
> > +     .reg_bits = 32,
> > +     .val_bits = 32,
> > +     .reg_stride = 4,
> > +     .fast_io = true,
> > +};
> > +
> > +static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
> > +{
> > +     wait_queue_head_t *data_wait;
> > +     struct ths_device *tmdev = data;
> > +     int i, state;
> > +
> > +     regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
> > +
> > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > +             data_wait = &tmdev->sensor[i].wait_queue;
>
> You're only using data_wait in that scope, so you should define it
> here.
>
> > +
> > +             if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
> > +                     /* clear data irq pending */
> > +                     regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
> > +                                  SUN50I_H6_THS_DATA_IRQ_STS(i));
> > +
> > +                     tmdev->data_ready |= BIT(i);
> > +                     wake_up(data_wait);
> > +             }
> > +     }
> > +
> > +     return IRQ_HANDLED;
> > +}
> > +
> > +static int sun8i_ths_resource_init(struct ths_device *tmdev)
> > +{
> > +     struct device *dev = tmdev->dev;
> > +     struct platform_device *pdev = to_platform_device(dev);
> > +     struct resource *mem;
> > +     void __iomem *base;
> > +     int ret, irq;
> > +
> > +     mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +     base = devm_ioremap_resource(dev, mem);
> > +     if (IS_ERR(base))
> > +             return PTR_ERR(base);
> > +
> > +     tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
> > +     if (IS_ERR(tmdev->regmap))
> > +             return PTR_ERR(tmdev->regmap);
> > +
> > +     tmdev->reset = devm_reset_control_get(dev, 0);
> > +     if (IS_ERR(tmdev->reset))
> > +             return PTR_ERR(tmdev->reset);
> > +
> > +     tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
> > +     if (IS_ERR(tmdev->bus_clk))
> > +             return PTR_ERR(tmdev->bus_clk);
> > +
> > +     irq = platform_get_irq(pdev, 0);
> > +     if (irq < 0)
> > +             return irq;
> > +
> > +     ret = devm_request_threaded_irq(dev, irq, NULL,
> > +                                     tmdev->chip->irq_thread,
> > +                                     IRQF_ONESHOT, "ths", tmdev);
> > +     if (ret)
> > +             return ret;
>
> Is there any particular reason to use a threaded interrupt?

Just to improve real-time.

>
> Also, starting from here you can start having interrupts...
>
> > +
> > +     ret = reset_control_deassert(tmdev->reset);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = clk_prepare_enable(tmdev->bus_clk);
> > +     if (ret)
> > +             goto assert_reset;
> > +
> > +     ret = tmdev->chip->calibrate(tmdev);
> > +     if (ret)
> > +             goto bus_disable;
>
> While the device hasn't been properly initialized yet. Especially when
> held in reset, some Allwinner controllers has been known to send
> spurious interrupts, so we want to defer that to the very last minute
> (so right before your call to sun8i_ths_register).
>
> > +     return 0;
> > +
> > +bus_disable:
> > +     clk_disable_unprepare(tmdev->bus_clk);
> > +assert_reset:
> > +     reset_control_assert(tmdev->reset);
> > +
> > +     return ret;
> > +}
> > +
> > +static int sun50i_ths_calibrate(struct ths_device *tmdev)
> > +{
> > +     struct nvmem_cell *calcell;
> > +     struct device *dev = tmdev->dev;
> > +     u16 *caldata;
> > +     size_t callen;
> > +     int ft_temp;
> > +     int i, ret = 0;
> > +
> > +     calcell = devm_nvmem_cell_get(dev, "calib");
> > +     if (IS_ERR(calcell)) {
> > +             if (PTR_ERR(calcell) == -EPROBE_DEFER)
> > +                     return -EPROBE_DEFER;
> > +             /*
> > +              * Even if the external calibration data stored in sid is
> > +              * not accessible, the THS hardware can still work, although
> > +              * the data won't be so accurate.
> > +              *
> > +              * The default value of calibration register is 0x800 for
> > +              * every sensor, and the calibration value is usually 0x7xx
> > +              * or 0x8xx, so they won't be away from the default value
> > +              * for a lot.
> > +              *
> > +              * So here we do not return error if the calibartion data is
> > +              * not available, except the probe needs deferring.
> > +              */
> > +             goto out;
> > +     }
> > +
> > +     caldata = nvmem_cell_read(calcell, &callen);
> > +     if (IS_ERR(caldata)) {
> > +             ret = PTR_ERR(caldata);
> > +             goto out;
> > +     }
> > +
> > +     if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) {
> > +             ret = -EINVAL;
> > +             goto out_free;
> > +     }
> > +
> > +     /*
> > +      * efuse layout:
> > +      *
> > +      *      0   11  16       32
> > +      *      +-------+-------+-------+
> > +      *      |temp|  |sensor0|sensor1|
> > +      *      +-------+-------+-------+
> > +      *
> > +      * The calibration data on the H6 is the ambient temperature and
> > +      * sensor values that are filled during the factory test stage.
> > +      *
> > +      * The unit of stored FT temperature is 0.1 degreee celusis.
> > +      * Through the stored ambient temperature and the data read
> > +      * by the sensor, after a certain calculation, the calibration
> > +      * value to be compensated can be obtained.
> > +      */
> > +     ft_temp = caldata[0] & FT_TEMP_MASK;
> > +
> > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > +             int reg = (int)caldata[i + 1];
> > +             int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
> > +             int delta, cdata, calib_offest;
> > +
> > +             /*
> > +              * To calculate the calibration value:
> > +              *
> > +              * X(in Celsius) = Ts - ft_temp
> > +              * delta = X * 10000 / TEMP_TO_REG
> > +              * cdata = CALIBRATE_DEFAULT - delta
> > +              *
> > +              * cdata: calibration value
> > +              */
> > +             delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
> > +             cdata = CALIBRATE_DEFAULT - delta;
> > +             if (cdata & ~TEMP_CALIB_MASK) {
> > +                     /*
> > +                      * Calibration value more than 12-bit, but calibration
> > +                      * register is 12-bit. In this case, ths hardware can
> > +                      * still work without calibration, although the data
> > +                      * won't be so accurate.
> > +                      */
> > +                     dev_warn(dev, "sensor%d is not calibrated.\n", i);
> > +
> > +                     continue;
> > +             }
> > +
> > +             calib_offest = tmdev->chip->temp_calib_base + (i / 2) * 0x4;
> > +
> > +             if (i % 2) {
> > +                     int val;
> > +
> > +                     regmap_read(tmdev->regmap, calib_offest, &val);
> > +                     val = (val & TEMP_CALIB_MASK) | (cdata << 16);
> > +                     regmap_write(tmdev->regmap, calib_offest, val);
> > +             } else {
> > +                     regmap_write(tmdev->regmap, calib_offest, cdata);
> > +             }
> > +     }
> > +
> > +out_free:
> > +     kfree(caldata);
> > +out:
> > +     return ret;
> > +}
> > +
> > +static int sun8i_ths_register(struct ths_device *tmdev)
> > +{
> > +     struct thermal_zone_device *tzd;
> > +     int i;
> > +
> > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > +             tmdev->sensor[i].tmdev = tmdev;
> > +             tmdev->sensor[i].id = i;
> > +             tmdev->sensor[i].tzd =
> > +                     devm_thermal_zone_of_sensor_register(tmdev->dev,
> > +                                                          i,
> > +                                                          &tmdev->sensor[i],
> > +                                                          &ths_ops);
> > +             if (IS_ERR(tmdev->sensor[i].tzd))
> > +                     return PTR_ERR(tzd);
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int sun8i_ths_probe(struct platform_device *pdev)
> > +{
> > +     struct ths_device *tmdev;
> > +     struct device *dev = &pdev->dev;
> > +     int i, ret;
> > +
> > +     tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
> > +     if (!tmdev)
> > +             return -ENOMEM;
> > +
> > +     tmdev->dev = dev;
> > +     tmdev->chip = of_device_get_match_data(&pdev->dev);
> > +     if (!tmdev->chip)
> > +             return -EINVAL;
> > +
> > +     /*
> > +      * Initialize wait_queue in advance, to avoid calling wake_up
> > +      * before ths is registered in isr.
> > +      */
> > +     for (i = 0; i < tmdev->chip->sensor_num; i++)
> > +             init_waitqueue_head(&tmdev->sensor[i].wait_queue);
> > +
> > +     platform_set_drvdata(pdev, tmdev);
> > +
> > +     ret = sun8i_ths_resource_init(tmdev);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = tmdev->chip->init(tmdev);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = sun8i_ths_register(tmdev);
> > +     if (ret)
> > +             return ret;
> > +
> > +     return ret;
> > +}
> > +
> > +static int sun8i_ths_remove(struct platform_device *pdev)
> > +{
> > +     struct ths_device *tmdev = platform_get_drvdata(pdev);
> > +
> > +     clk_disable_unprepare(tmdev->bus_clk);
>
> I know that we discussed that already, but I'm not sure why you switch
> back to a regular call to regmap_init_mmio, while regmap_init_mmio_clk
> will take care of enabling and disabling the bus clock for you?

It seems that regmap_init_mmio_clk just get clk and prepare clk
but no enable.

Yangtao
>
> Maxime
>
> --
> Maxime Ripard, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com

Yangtao Li June 7, 2019, 1:50 p.m. UTC | #4

HI Ondřej,


On Mon, May 27, 2019 at 10:25 PM Ondřej Jirman <[e-mail]> wrote:
>
> Hi Yangtao,
>
> On Sat, May 25, 2019 at 02:13:27PM -0400, Yangtao Li wrote:
> > This patch adds the support for allwinner thermal sensor, within
> > allwinner SoC. It will register sensors for thermal framework
> > and use device tree to bind cooling device.
> >
> > Signed-off-by: Yangtao Li <[e-mail]>
> > ---
> >  MAINTAINERS                     |   7 +
> >  drivers/thermal/Kconfig         |  14 +
> >  drivers/thermal/Makefile        |   1 +
> >  drivers/thermal/sun8i_thermal.c | 437 ++++++++++++++++++++++++++++++++
> >  4 files changed, 459 insertions(+)
> >  create mode 100644 drivers/thermal/sun8i_thermal.c
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 2336dd26ece4..d312f9eecf0d 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -674,6 +674,13 @@ L:       [e-mail]
> >  S:   Maintained
> >  F:   drivers/crypto/sunxi-ss/
> >
> > +ALLWINNER THERMAL DRIVER
> > +M:   Yangtao Li <[e-mail]>
> > +L:   [e-mail]
> > +S:   Maintained
> > +F:   Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
> > +F:   drivers/thermal/sun8i_thermal.c
> > +
> >  ALLWINNER VPU DRIVER
> >  M:   Maxime Ripard <[e-mail]>
> >  M:   Paul Kocialkowski <[e-mail]>
> > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> > index 9966364a6deb..e5465053d66f 100644
> > --- a/drivers/thermal/Kconfig
> > +++ b/drivers/thermal/Kconfig
> > @@ -262,6 +262,20 @@ config SPEAR_THERMAL
> >         Enable this to plug the SPEAr thermal sensor driver into the Linux
> >         thermal framework.
> >
> > +config SUN8I_THERMAL
> > +     tristate "Allwinner sun8i thermal driver"
> > +     depends on ARCH_SUNXI || COMPILE_TEST
> > +     depends on HAS_IOMEM
> > +     depends on NVMEM_SUNXI_SID
> > +     depends on OF
> > +     depends on RESET_CONTROLLER
> > +     help
> > +       Support for the sun8i thermal sensor driver into the Linux thermal
> > +       framework.
> > +
> > +       To compile this driver as a module, choose M here: the
> > +       module will be called sun8i-thermal.
> > +
> >  config ROCKCHIP_THERMAL
> >       tristate "Rockchip thermal driver"
> >       depends on ARCH_ROCKCHIP || COMPILE_TEST
> > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> > index 74a37c7f847a..fa6f8b206281 100644
> > --- a/drivers/thermal/Makefile
> > +++ b/drivers/thermal/Makefile
> > @@ -31,6 +31,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
> >  obj-y                                += broadcom/
> >  obj-$(CONFIG_THERMAL_MMIO)           += thermal_mmio.o
> >  obj-$(CONFIG_SPEAR_THERMAL)  += spear_thermal.o
> > +obj-$(CONFIG_SUN8I_THERMAL)     += sun8i_thermal.o
> >  obj-$(CONFIG_ROCKCHIP_THERMAL)       += rockchip_thermal.o
> >  obj-$(CONFIG_RCAR_THERMAL)   += rcar_thermal.o
> >  obj-$(CONFIG_RCAR_GEN3_THERMAL)      += rcar_gen3_thermal.o
> > diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
> > new file mode 100644
> > index 000000000000..a9cc2197f4cb
> > --- /dev/null
> > +++ b/drivers/thermal/sun8i_thermal.c
> > @@ -0,0 +1,437 @@
> > +// SPDX-License-Identifier: GPL-2.0
> > +/*
> > + * Thermal sensor driver for Allwinner SOC
> > + * Copyright (C) 2019 Yangtao Li
> > + *
> > + * Based on the work of Icenowy Zheng <[e-mail]>
> > + * Based on the work of Ondrej Jirman <[e-mail]>
> > + * Based on the work of Josef Gajdusek <[e-mail]>
> > + */
> > +
> > +#include <linux/clk.h>
> > +#include <linux/device.h>
> > +#include <linux/interrupt.h>
> > +#include <linux/wait.h>
> > +#include <linux/module.h>
> > +#include <linux/nvmem-consumer.h>
> > +#include <linux/of_device.h>
> > +#include <linux/platform_device.h>
> > +#include <linux/regmap.h>
> > +#include <linux/reset.h>
> > +#include <linux/slab.h>
> > +#include <linux/thermal.h>
> > +
> > +#define MAX_SENSOR_NUM       4
> > +
> > +#define FT_TEMP_MASK                         GENMASK(11, 0)
> > +#define TEMP_CALIB_MASK                              GENMASK(11, 0)
> > +#define TEMP_TO_REG                          672
> > +#define CALIBRATE_DEFAULT                    0x800
> > +
> > +#define SUN50I_THS_CTRL0                     0x00
> > +#define SUN50I_H6_THS_ENABLE                 0x04
> > +#define SUN50I_H6_THS_PC                     0x08
> > +#define SUN50I_H6_THS_DIC                    0x10
> > +#define SUN50I_H6_THS_DIS                    0x20
> > +#define SUN50I_H6_THS_MFC                    0x30
> > +#define SUN50I_H6_THS_TEMP_CALIB             0xa0
> > +#define SUN50I_H6_THS_TEMP_DATA                      0xc0
> > +
> > +#define SUN50I_THS_CTRL0_T_ACQ(x)            ((GENMASK(15, 0) & (x)) << 16)
> > +#define SUN50I_THS_FILTER_EN                 BIT(2)
> > +#define SUN50I_THS_FILTER_TYPE(x)            (GENMASK(1, 0) & (x))
> > +#define SUN50I_H6_THS_PC_TEMP_PERIOD(x)              ((GENMASK(19, 0) & (x)) << 12)
> > +#define SUN50I_H6_THS_DATA_IRQ_STS(x)                BIT(x)
> > +
> > +/* millidegree celsius */
> > +#define SUN50I_H6_FT_DEVIATION                       7000
> > +
> > +struct ths_device;
> > +
> > +struct tsensor {
> > +     struct ths_device               *tmdev;
> > +     struct thermal_zone_device      *tzd;
> > +     int                             id;
> > +     wait_queue_head_t               wait_queue;
> > +};
> > +
> > +struct ths_thermal_chip {
> > +     int             sensor_num;
> > +     int             offset;
> > +     int             scale;
> > +     int             ft_deviation;
> > +     int             temp_calib_base;
> > +     int             temp_data_base;
> > +     int             (*calibrate)(struct ths_device *tmdev);
> > +     int             (*init)(struct ths_device *tmdev);
> > +     irqreturn_t     (*irq_thread)(int irq, void *data);
> > +};
> > +
> > +struct ths_device {
> > +     const struct ths_thermal_chip           *chip;
> > +     struct device                           *dev;
> > +     struct regmap                           *regmap;
> > +     struct reset_control                    *reset;
> > +     struct clk                              *bus_clk;
> > +     struct tsensor                          sensor[MAX_SENSOR_NUM];
> > +     int                                     data_ready;
> > +};
> > +
> > +/* Temp Unit: millidegree Celsius */
> > +static int sun8i_ths_reg2temp(struct ths_device *tmdev,
> > +                           int reg)
> > +{
> > +     return (reg + tmdev->chip->offset) * tmdev->chip->scale;
> > +}
> > +
> > +static int sun8i_ths_get_temp(void *data, int *temp)
> > +{
> > +     struct tsensor *s = data;
> > +     struct ths_device *tmdev = s->tmdev;
> > +     int val;
> > +
> > +     wait_event(s->wait_queue, tmdev->data_ready & BIT(s->id));
> > +     tmdev->data_ready &= ~BIT(s->id);
>
> I've looked at thermal_core.c and it looks like that the proper way to handle
> this situation is just returning -EAGAIN.

What we are doing now is to turn it into an interrupt-based program.
Every time we use temperature data, we need to wait until new data is collected.

>
> See update_temperature() function in thermal_core.c.
>
> That will suppress the warning about failure to read thermal zone. Also
> it's much simpler than this wait_queue stuff. No other thermal driver uses this
> either. Also get_temp is called under thermal_list_lock mutex and that would
> block cooling device registrations and god knows what else.

Since there is no valid temperature data, it cannot be blocked.

MBR,
Yangtao

>
> Other than that, and what Maxime said, I don't see any more issues.
>
> thank you,
>         o.
>
> > +     regmap_read(tmdev->regmap, tmdev->chip->temp_data_base +
> > +                 0x4 * s->id, &val);
> > +
> > +     *temp = sun8i_ths_reg2temp(tmdev, val);
> > +     /*
> > +      * XX - According to the original sdk, there are some platforms(rarely)
> > +      * that add a fixed offset value after calculating the temperature
> > +      * value. We can't simply put it on the formula for calculating the
> > +      * temperature above, because the formula for calculating the
> > +      * temperature above is also used when the sensor is calibrated. If
> > +      * do this, the correct calibration formula is hard to know.
> > +      */
> > +     if (tmdev->chip->ft_deviation)
> > +             *temp += tmdev->chip->ft_deviation;
> > +
> > +     return 0;
> > +}
> > +
> > +static const struct thermal_zone_of_device_ops ths_ops = {
> > +     .get_temp = sun8i_ths_get_temp,
> > +};
> > +
> > +static const struct regmap_config config = {
> > +     .reg_bits = 32,
> > +     .val_bits = 32,
> > +     .reg_stride = 4,
> > +     .fast_io = true,
> > +};
> > +
> > +static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
> > +{
> > +     wait_queue_head_t *data_wait;
> > +     struct ths_device *tmdev = data;
> > +     int i, state;
> > +
> > +     regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
> > +
> > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > +             data_wait = &tmdev->sensor[i].wait_queue;
> > +
> > +             if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
> > +                     /* clear data irq pending */
> > +                     regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
> > +                                  SUN50I_H6_THS_DATA_IRQ_STS(i));
> > +
> > +                     tmdev->data_ready |= BIT(i);
> > +                     wake_up(data_wait);
> > +             }
> > +     }
> > +
> > +     return IRQ_HANDLED;
> > +}
> > +
> > +static int sun8i_ths_resource_init(struct ths_device *tmdev)
> > +{
> > +     struct device *dev = tmdev->dev;
> > +     struct platform_device *pdev = to_platform_device(dev);
> > +     struct resource *mem;
> > +     void __iomem *base;
> > +     int ret, irq;
> > +
> > +     mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > +     base = devm_ioremap_resource(dev, mem);
> > +     if (IS_ERR(base))
> > +             return PTR_ERR(base);
> > +
> > +     tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
> > +     if (IS_ERR(tmdev->regmap))
> > +             return PTR_ERR(tmdev->regmap);
> > +
> > +     tmdev->reset = devm_reset_control_get(dev, 0);
> > +     if (IS_ERR(tmdev->reset))
> > +             return PTR_ERR(tmdev->reset);
> > +
> > +     tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
> > +     if (IS_ERR(tmdev->bus_clk))
> > +             return PTR_ERR(tmdev->bus_clk);
> > +
> > +     irq = platform_get_irq(pdev, 0);
> > +     if (irq < 0)
> > +             return irq;
> > +
> > +     ret = devm_request_threaded_irq(dev, irq, NULL,
> > +                                     tmdev->chip->irq_thread,
> > +                                     IRQF_ONESHOT, "ths", tmdev);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = reset_control_deassert(tmdev->reset);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = clk_prepare_enable(tmdev->bus_clk);
> > +     if (ret)
> > +             goto assert_reset;
> > +
> > +     ret = tmdev->chip->calibrate(tmdev);
> > +     if (ret)
> > +             goto bus_disable;
> > +
> > +     return 0;
> > +
> > +bus_disable:
> > +     clk_disable_unprepare(tmdev->bus_clk);
> > +assert_reset:
> > +     reset_control_assert(tmdev->reset);
> > +
> > +     return ret;
> > +}
> > +
> > +static int sun50i_ths_calibrate(struct ths_device *tmdev)
> > +{
> > +     struct nvmem_cell *calcell;
> > +     struct device *dev = tmdev->dev;
> > +     u16 *caldata;
> > +     size_t callen;
> > +     int ft_temp;
> > +     int i, ret = 0;
> > +
> > +     calcell = devm_nvmem_cell_get(dev, "calib");
> > +     if (IS_ERR(calcell)) {
> > +             if (PTR_ERR(calcell) == -EPROBE_DEFER)
> > +                     return -EPROBE_DEFER;
> > +             /*
> > +              * Even if the external calibration data stored in sid is
> > +              * not accessible, the THS hardware can still work, although
> > +              * the data won't be so accurate.
> > +              *
> > +              * The default value of calibration register is 0x800 for
> > +              * every sensor, and the calibration value is usually 0x7xx
> > +              * or 0x8xx, so they won't be away from the default value
> > +              * for a lot.
> > +              *
> > +              * So here we do not return error if the calibartion data is
> > +              * not available, except the probe needs deferring.
> > +              */
> > +             goto out;
> > +     }
> > +
> > +     caldata = nvmem_cell_read(calcell, &callen);
> > +     if (IS_ERR(caldata)) {
> > +             ret = PTR_ERR(caldata);
> > +             goto out;
> > +     }
> > +
> > +     if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) {
> > +             ret = -EINVAL;
> > +             goto out_free;
> > +     }
> > +
> > +     /*
> > +      * efuse layout:
> > +      *
> > +      *      0   11  16       32
> > +      *      +-------+-------+-------+
> > +      *      |temp|  |sensor0|sensor1|
> > +      *      +-------+-------+-------+
> > +      *
> > +      * The calibration data on the H6 is the ambient temperature and
> > +      * sensor values that are filled during the factory test stage.
> > +      *
> > +      * The unit of stored FT temperature is 0.1 degreee celusis.
> > +      * Through the stored ambient temperature and the data read
> > +      * by the sensor, after a certain calculation, the calibration
> > +      * value to be compensated can be obtained.
> > +      */
> > +     ft_temp = caldata[0] & FT_TEMP_MASK;
> > +
> > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > +             int reg = (int)caldata[i + 1];
> > +             int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
> > +             int delta, cdata, calib_offest;
> > +
> > +             /*
> > +              * To calculate the calibration value:
> > +              *
> > +              * X(in Celsius) = Ts - ft_temp
> > +              * delta = X * 10000 / TEMP_TO_REG
> > +              * cdata = CALIBRATE_DEFAULT - delta
> > +              *
> > +              * cdata: calibration value
> > +              */
> > +             delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
> > +             cdata = CALIBRATE_DEFAULT - delta;
> > +             if (cdata & ~TEMP_CALIB_MASK) {
> > +                     /*
> > +                      * Calibration value more than 12-bit, but calibration
> > +                      * register is 12-bit. In this case, ths hardware can
> > +                      * still work without calibration, although the data
> > +                      * won't be so accurate.
> > +                      */
> > +                     dev_warn(dev, "sensor%d is not calibrated.\n", i);
> > +
> > +                     continue;
> > +             }
> > +
> > +             calib_offest = tmdev->chip->temp_calib_base + (i / 2) * 0x4;
> > +
> > +             if (i % 2) {
> > +                     int val;
> > +
> > +                     regmap_read(tmdev->regmap, calib_offest, &val);
> > +                     val = (val & TEMP_CALIB_MASK) | (cdata << 16);
> > +                     regmap_write(tmdev->regmap, calib_offest, val);
> > +             } else {
> > +                     regmap_write(tmdev->regmap, calib_offest, cdata);
> > +             }
> > +     }
> > +
> > +out_free:
> > +     kfree(caldata);
> > +out:
> > +     return ret;
> > +}
> > +
> > +static int sun8i_ths_register(struct ths_device *tmdev)
> > +{
> > +     struct thermal_zone_device *tzd;
> > +     int i;
> > +
> > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > +             tmdev->sensor[i].tmdev = tmdev;
> > +             tmdev->sensor[i].id = i;
> > +             tmdev->sensor[i].tzd =
> > +                     devm_thermal_zone_of_sensor_register(tmdev->dev,
> > +                                                          i,
> > +                                                          &tmdev->sensor[i],
> > +                                                          &ths_ops);
> > +             if (IS_ERR(tmdev->sensor[i].tzd))
> > +                     return PTR_ERR(tzd);
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +static int sun8i_ths_probe(struct platform_device *pdev)
> > +{
> > +     struct ths_device *tmdev;
> > +     struct device *dev = &pdev->dev;
> > +     int i, ret;
> > +
> > +     tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
> > +     if (!tmdev)
> > +             return -ENOMEM;
> > +
> > +     tmdev->dev = dev;
> > +     tmdev->chip = of_device_get_match_data(&pdev->dev);
> > +     if (!tmdev->chip)
> > +             return -EINVAL;
> > +
> > +     /*
> > +      * Initialize wait_queue in advance, to avoid calling wake_up
> > +      * before ths is registered in isr.
> > +      */
> > +     for (i = 0; i < tmdev->chip->sensor_num; i++)
> > +             init_waitqueue_head(&tmdev->sensor[i].wait_queue);
> > +
> > +     platform_set_drvdata(pdev, tmdev);
> > +
> > +     ret = sun8i_ths_resource_init(tmdev);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = tmdev->chip->init(tmdev);
> > +     if (ret)
> > +             return ret;
> > +
> > +     ret = sun8i_ths_register(tmdev);
> > +     if (ret)
> > +             return ret;
> > +
> > +     return ret;
> > +}
> > +
> > +static int sun8i_ths_remove(struct platform_device *pdev)
> > +{
> > +     struct ths_device *tmdev = platform_get_drvdata(pdev);
> > +
> > +     clk_disable_unprepare(tmdev->bus_clk);
> > +     reset_control_assert(tmdev->reset);
> > +
> > +     return 0;
> > +}
> > +
> > +static int sun50i_thermal_init(struct ths_device *tmdev)
> > +{
> > +     int val;
> > +
> > +     /*
> > +      * clkin = 24MHz
> > +      * T acquire = clkin / (x + 1)
> > +      *           = 20us
> > +      */
> > +     regmap_write(tmdev->regmap, SUN50I_THS_CTRL0,
> > +                  SUN50I_THS_CTRL0_T_ACQ(479));
> > +     /* average over 4 samples */
> > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC,
> > +                  SUN50I_THS_FILTER_EN |
> > +                  SUN50I_THS_FILTER_TYPE(1));
> > +     /* period = (x + 1) * 4096 / clkin; ~10ms */
> > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_PC,
> > +                  SUN50I_H6_THS_PC_TEMP_PERIOD(58));
> > +     /* enable sensor */
> > +     val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val);
> > +     /* thermal data interrupt enable */
> > +     val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_DIC, val);
> > +
> > +     return 0;
> > +}
> > +
> > +static const struct ths_thermal_chip sun50i_h6_ths = {
> > +     .sensor_num = 2,
> > +     .offset = -2794,
> > +     .scale = -67,
> > +     .ft_deviation = SUN50I_H6_FT_DEVIATION,
> > +     .temp_calib_base = SUN50I_H6_THS_TEMP_CALIB,
> > +     .temp_data_base = SUN50I_H6_THS_TEMP_DATA,
> > +     .calibrate = sun50i_ths_calibrate,
> > +     .init = sun50i_thermal_init,
> > +     .irq_thread = sun50i_h6_irq_thread,
> > +};
> > +
> > +static const struct of_device_id of_ths_match[] = {
> > +     { .compatible = "allwinner,sun50i-h6-ths", .data = &sun50i_h6_ths },
> > +     { /* sentinel */ },
> > +};
> > +MODULE_DEVICE_TABLE(of, of_ths_match);
> > +
> > +static struct platform_driver ths_driver = {
> > +     .probe = sun8i_ths_probe,
> > +     .remove = sun8i_ths_remove,
> > +     .driver = {
> > +             .name = "sun8i-thermal",
> > +             .of_match_table = of_ths_match,
> > +     },
> > +};
> > +module_platform_driver(ths_driver);
> > +
> > +MODULE_DESCRIPTION("Thermal sensor driver for Allwinner SOC");
> > +MODULE_LICENSE("GPL v2");
> > --
> > 2.17.0
> >
> >
> > _______________________________________________
> > linux-arm-kernel mailing list
> > [e-mail]
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Yangtao Li June 7, 2019, 1:52 p.m. UTC | #5

On Fri, Jun 7, 2019 at 9:50 PM Frank Lee <[e-mail]> wrote:
>
> HI Ondřej,
>
>
> On Mon, May 27, 2019 at 10:25 PM Ondřej Jirman <[e-mail]> wrote:
> >
> > Hi Yangtao,
> >
> > On Sat, May 25, 2019 at 02:13:27PM -0400, Yangtao Li wrote:
> > > This patch adds the support for allwinner thermal sensor, within
> > > allwinner SoC. It will register sensors for thermal framework
> > > and use device tree to bind cooling device.
> > >
> > > Signed-off-by: Yangtao Li <[e-mail]>
> > > ---
> > >  MAINTAINERS                     |   7 +
> > >  drivers/thermal/Kconfig         |  14 +
> > >  drivers/thermal/Makefile        |   1 +
> > >  drivers/thermal/sun8i_thermal.c | 437 ++++++++++++++++++++++++++++++++
> > >  4 files changed, 459 insertions(+)
> > >  create mode 100644 drivers/thermal/sun8i_thermal.c
> > >
> > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > index 2336dd26ece4..d312f9eecf0d 100644
> > > --- a/MAINTAINERS
> > > +++ b/MAINTAINERS
> > > @@ -674,6 +674,13 @@ L:       [e-mail]
> > >  S:   Maintained
> > >  F:   drivers/crypto/sunxi-ss/
> > >
> > > +ALLWINNER THERMAL DRIVER
> > > +M:   Yangtao Li <[e-mail]>
> > > +L:   [e-mail]
> > > +S:   Maintained
> > > +F:   Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
> > > +F:   drivers/thermal/sun8i_thermal.c
> > > +
> > >  ALLWINNER VPU DRIVER
> > >  M:   Maxime Ripard <[e-mail]>
> > >  M:   Paul Kocialkowski <[e-mail]>
> > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> > > index 9966364a6deb..e5465053d66f 100644
> > > --- a/drivers/thermal/Kconfig
> > > +++ b/drivers/thermal/Kconfig
> > > @@ -262,6 +262,20 @@ config SPEAR_THERMAL
> > >         Enable this to plug the SPEAr thermal sensor driver into the Linux
> > >         thermal framework.
> > >
> > > +config SUN8I_THERMAL
> > > +     tristate "Allwinner sun8i thermal driver"
> > > +     depends on ARCH_SUNXI || COMPILE_TEST
> > > +     depends on HAS_IOMEM
> > > +     depends on NVMEM_SUNXI_SID
> > > +     depends on OF
> > > +     depends on RESET_CONTROLLER
> > > +     help
> > > +       Support for the sun8i thermal sensor driver into the Linux thermal
> > > +       framework.
> > > +
> > > +       To compile this driver as a module, choose M here: the
> > > +       module will be called sun8i-thermal.
> > > +
> > >  config ROCKCHIP_THERMAL
> > >       tristate "Rockchip thermal driver"
> > >       depends on ARCH_ROCKCHIP || COMPILE_TEST
> > > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> > > index 74a37c7f847a..fa6f8b206281 100644
> > > --- a/drivers/thermal/Makefile
> > > +++ b/drivers/thermal/Makefile
> > > @@ -31,6 +31,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
> > >  obj-y                                += broadcom/
> > >  obj-$(CONFIG_THERMAL_MMIO)           += thermal_mmio.o
> > >  obj-$(CONFIG_SPEAR_THERMAL)  += spear_thermal.o
> > > +obj-$(CONFIG_SUN8I_THERMAL)     += sun8i_thermal.o
> > >  obj-$(CONFIG_ROCKCHIP_THERMAL)       += rockchip_thermal.o
> > >  obj-$(CONFIG_RCAR_THERMAL)   += rcar_thermal.o
> > >  obj-$(CONFIG_RCAR_GEN3_THERMAL)      += rcar_gen3_thermal.o
> > > diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
> > > new file mode 100644
> > > index 000000000000..a9cc2197f4cb
> > > --- /dev/null
> > > +++ b/drivers/thermal/sun8i_thermal.c
> > > @@ -0,0 +1,437 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +/*
> > > + * Thermal sensor driver for Allwinner SOC
> > > + * Copyright (C) 2019 Yangtao Li
> > > + *
> > > + * Based on the work of Icenowy Zheng <[e-mail]>
> > > + * Based on the work of Ondrej Jirman <[e-mail]>
> > > + * Based on the work of Josef Gajdusek <[e-mail]>
> > > + */
> > > +
> > > +#include <linux/clk.h>
> > > +#include <linux/device.h>
> > > +#include <linux/interrupt.h>
> > > +#include <linux/wait.h>
> > > +#include <linux/module.h>
> > > +#include <linux/nvmem-consumer.h>
> > > +#include <linux/of_device.h>
> > > +#include <linux/platform_device.h>
> > > +#include <linux/regmap.h>
> > > +#include <linux/reset.h>
> > > +#include <linux/slab.h>
> > > +#include <linux/thermal.h>
> > > +
> > > +#define MAX_SENSOR_NUM       4
> > > +
> > > +#define FT_TEMP_MASK                         GENMASK(11, 0)
> > > +#define TEMP_CALIB_MASK                              GENMASK(11, 0)
> > > +#define TEMP_TO_REG                          672
> > > +#define CALIBRATE_DEFAULT                    0x800
> > > +
> > > +#define SUN50I_THS_CTRL0                     0x00
> > > +#define SUN50I_H6_THS_ENABLE                 0x04
> > > +#define SUN50I_H6_THS_PC                     0x08
> > > +#define SUN50I_H6_THS_DIC                    0x10
> > > +#define SUN50I_H6_THS_DIS                    0x20
> > > +#define SUN50I_H6_THS_MFC                    0x30
> > > +#define SUN50I_H6_THS_TEMP_CALIB             0xa0
> > > +#define SUN50I_H6_THS_TEMP_DATA                      0xc0
> > > +
> > > +#define SUN50I_THS_CTRL0_T_ACQ(x)            ((GENMASK(15, 0) & (x)) << 16)
> > > +#define SUN50I_THS_FILTER_EN                 BIT(2)
> > > +#define SUN50I_THS_FILTER_TYPE(x)            (GENMASK(1, 0) & (x))
> > > +#define SUN50I_H6_THS_PC_TEMP_PERIOD(x)              ((GENMASK(19, 0) & (x)) << 12)
> > > +#define SUN50I_H6_THS_DATA_IRQ_STS(x)                BIT(x)
> > > +
> > > +/* millidegree celsius */
> > > +#define SUN50I_H6_FT_DEVIATION                       7000
> > > +
> > > +struct ths_device;
> > > +
> > > +struct tsensor {
> > > +     struct ths_device               *tmdev;
> > > +     struct thermal_zone_device      *tzd;
> > > +     int                             id;
> > > +     wait_queue_head_t               wait_queue;
> > > +};
> > > +
> > > +struct ths_thermal_chip {
> > > +     int             sensor_num;
> > > +     int             offset;
> > > +     int             scale;
> > > +     int             ft_deviation;
> > > +     int             temp_calib_base;
> > > +     int             temp_data_base;
> > > +     int             (*calibrate)(struct ths_device *tmdev);
> > > +     int             (*init)(struct ths_device *tmdev);
> > > +     irqreturn_t     (*irq_thread)(int irq, void *data);
> > > +};
> > > +
> > > +struct ths_device {
> > > +     const struct ths_thermal_chip           *chip;
> > > +     struct device                           *dev;
> > > +     struct regmap                           *regmap;
> > > +     struct reset_control                    *reset;
> > > +     struct clk                              *bus_clk;
> > > +     struct tsensor                          sensor[MAX_SENSOR_NUM];
> > > +     int                                     data_ready;
> > > +};
> > > +
> > > +/* Temp Unit: millidegree Celsius */
> > > +static int sun8i_ths_reg2temp(struct ths_device *tmdev,
> > > +                           int reg)
> > > +{
> > > +     return (reg + tmdev->chip->offset) * tmdev->chip->scale;
> > > +}
> > > +
> > > +static int sun8i_ths_get_temp(void *data, int *temp)
> > > +{
> > > +     struct tsensor *s = data;
> > > +     struct ths_device *tmdev = s->tmdev;
> > > +     int val;
> > > +
> > > +     wait_event(s->wait_queue, tmdev->data_ready & BIT(s->id));
> > > +     tmdev->data_ready &= ~BIT(s->id);
> >
> > I've looked at thermal_core.c and it looks like that the proper way to handle
> > this situation is just returning -EAGAIN.
>
> What we are doing now is to turn it into an interrupt-based program.
> Every time we use temperature data, we need to wait until new data is collected.
>
> >
> > See update_temperature() function in thermal_core.c.
> >
> > That will suppress the warning about failure to read thermal zone. Also
> > it's much simpler than this wait_queue stuff. No other thermal driver uses this
> > either. Also get_temp is called under thermal_list_lock mutex and that would
> > block cooling device registrations and god knows what else.
>
> Since there is no valid temperature data, it cannot be blocked.

Since there is no valid temperature data, why can't it be blocked?

>
> MBR,
> Yangtao
>
> >
> > Other than that, and what Maxime said, I don't see any more issues.
> >
> > thank you,
> >         o.
> >
> > > +     regmap_read(tmdev->regmap, tmdev->chip->temp_data_base +
> > > +                 0x4 * s->id, &val);
> > > +
> > > +     *temp = sun8i_ths_reg2temp(tmdev, val);
> > > +     /*
> > > +      * XX - According to the original sdk, there are some platforms(rarely)
> > > +      * that add a fixed offset value after calculating the temperature
> > > +      * value. We can't simply put it on the formula for calculating the
> > > +      * temperature above, because the formula for calculating the
> > > +      * temperature above is also used when the sensor is calibrated. If
> > > +      * do this, the correct calibration formula is hard to know.
> > > +      */
> > > +     if (tmdev->chip->ft_deviation)
> > > +             *temp += tmdev->chip->ft_deviation;
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static const struct thermal_zone_of_device_ops ths_ops = {
> > > +     .get_temp = sun8i_ths_get_temp,
> > > +};
> > > +
> > > +static const struct regmap_config config = {
> > > +     .reg_bits = 32,
> > > +     .val_bits = 32,
> > > +     .reg_stride = 4,
> > > +     .fast_io = true,
> > > +};
> > > +
> > > +static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
> > > +{
> > > +     wait_queue_head_t *data_wait;
> > > +     struct ths_device *tmdev = data;
> > > +     int i, state;
> > > +
> > > +     regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
> > > +
> > > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > +             data_wait = &tmdev->sensor[i].wait_queue;
> > > +
> > > +             if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
> > > +                     /* clear data irq pending */
> > > +                     regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
> > > +                                  SUN50I_H6_THS_DATA_IRQ_STS(i));
> > > +
> > > +                     tmdev->data_ready |= BIT(i);
> > > +                     wake_up(data_wait);
> > > +             }
> > > +     }
> > > +
> > > +     return IRQ_HANDLED;
> > > +}
> > > +
> > > +static int sun8i_ths_resource_init(struct ths_device *tmdev)
> > > +{
> > > +     struct device *dev = tmdev->dev;
> > > +     struct platform_device *pdev = to_platform_device(dev);
> > > +     struct resource *mem;
> > > +     void __iomem *base;
> > > +     int ret, irq;
> > > +
> > > +     mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > +     base = devm_ioremap_resource(dev, mem);
> > > +     if (IS_ERR(base))
> > > +             return PTR_ERR(base);
> > > +
> > > +     tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
> > > +     if (IS_ERR(tmdev->regmap))
> > > +             return PTR_ERR(tmdev->regmap);
> > > +
> > > +     tmdev->reset = devm_reset_control_get(dev, 0);
> > > +     if (IS_ERR(tmdev->reset))
> > > +             return PTR_ERR(tmdev->reset);
> > > +
> > > +     tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
> > > +     if (IS_ERR(tmdev->bus_clk))
> > > +             return PTR_ERR(tmdev->bus_clk);
> > > +
> > > +     irq = platform_get_irq(pdev, 0);
> > > +     if (irq < 0)
> > > +             return irq;
> > > +
> > > +     ret = devm_request_threaded_irq(dev, irq, NULL,
> > > +                                     tmdev->chip->irq_thread,
> > > +                                     IRQF_ONESHOT, "ths", tmdev);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     ret = reset_control_deassert(tmdev->reset);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     ret = clk_prepare_enable(tmdev->bus_clk);
> > > +     if (ret)
> > > +             goto assert_reset;
> > > +
> > > +     ret = tmdev->chip->calibrate(tmdev);
> > > +     if (ret)
> > > +             goto bus_disable;
> > > +
> > > +     return 0;
> > > +
> > > +bus_disable:
> > > +     clk_disable_unprepare(tmdev->bus_clk);
> > > +assert_reset:
> > > +     reset_control_assert(tmdev->reset);
> > > +
> > > +     return ret;
> > > +}
> > > +
> > > +static int sun50i_ths_calibrate(struct ths_device *tmdev)
> > > +{
> > > +     struct nvmem_cell *calcell;
> > > +     struct device *dev = tmdev->dev;
> > > +     u16 *caldata;
> > > +     size_t callen;
> > > +     int ft_temp;
> > > +     int i, ret = 0;
> > > +
> > > +     calcell = devm_nvmem_cell_get(dev, "calib");
> > > +     if (IS_ERR(calcell)) {
> > > +             if (PTR_ERR(calcell) == -EPROBE_DEFER)
> > > +                     return -EPROBE_DEFER;
> > > +             /*
> > > +              * Even if the external calibration data stored in sid is
> > > +              * not accessible, the THS hardware can still work, although
> > > +              * the data won't be so accurate.
> > > +              *
> > > +              * The default value of calibration register is 0x800 for
> > > +              * every sensor, and the calibration value is usually 0x7xx
> > > +              * or 0x8xx, so they won't be away from the default value
> > > +              * for a lot.
> > > +              *
> > > +              * So here we do not return error if the calibartion data is
> > > +              * not available, except the probe needs deferring.
> > > +              */
> > > +             goto out;
> > > +     }
> > > +
> > > +     caldata = nvmem_cell_read(calcell, &callen);
> > > +     if (IS_ERR(caldata)) {
> > > +             ret = PTR_ERR(caldata);
> > > +             goto out;
> > > +     }
> > > +
> > > +     if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) {
> > > +             ret = -EINVAL;
> > > +             goto out_free;
> > > +     }
> > > +
> > > +     /*
> > > +      * efuse layout:
> > > +      *
> > > +      *      0   11  16       32
> > > +      *      +-------+-------+-------+
> > > +      *      |temp|  |sensor0|sensor1|
> > > +      *      +-------+-------+-------+
> > > +      *
> > > +      * The calibration data on the H6 is the ambient temperature and
> > > +      * sensor values that are filled during the factory test stage.
> > > +      *
> > > +      * The unit of stored FT temperature is 0.1 degreee celusis.
> > > +      * Through the stored ambient temperature and the data read
> > > +      * by the sensor, after a certain calculation, the calibration
> > > +      * value to be compensated can be obtained.
> > > +      */
> > > +     ft_temp = caldata[0] & FT_TEMP_MASK;
> > > +
> > > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > +             int reg = (int)caldata[i + 1];
> > > +             int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
> > > +             int delta, cdata, calib_offest;
> > > +
> > > +             /*
> > > +              * To calculate the calibration value:
> > > +              *
> > > +              * X(in Celsius) = Ts - ft_temp
> > > +              * delta = X * 10000 / TEMP_TO_REG
> > > +              * cdata = CALIBRATE_DEFAULT - delta
> > > +              *
> > > +              * cdata: calibration value
> > > +              */
> > > +             delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
> > > +             cdata = CALIBRATE_DEFAULT - delta;
> > > +             if (cdata & ~TEMP_CALIB_MASK) {
> > > +                     /*
> > > +                      * Calibration value more than 12-bit, but calibration
> > > +                      * register is 12-bit. In this case, ths hardware can
> > > +                      * still work without calibration, although the data
> > > +                      * won't be so accurate.
> > > +                      */
> > > +                     dev_warn(dev, "sensor%d is not calibrated.\n", i);
> > > +
> > > +                     continue;
> > > +             }
> > > +
> > > +             calib_offest = tmdev->chip->temp_calib_base + (i / 2) * 0x4;
> > > +
> > > +             if (i % 2) {
> > > +                     int val;
> > > +
> > > +                     regmap_read(tmdev->regmap, calib_offest, &val);
> > > +                     val = (val & TEMP_CALIB_MASK) | (cdata << 16);
> > > +                     regmap_write(tmdev->regmap, calib_offest, val);
> > > +             } else {
> > > +                     regmap_write(tmdev->regmap, calib_offest, cdata);
> > > +             }
> > > +     }
> > > +
> > > +out_free:
> > > +     kfree(caldata);
> > > +out:
> > > +     return ret;
> > > +}
> > > +
> > > +static int sun8i_ths_register(struct ths_device *tmdev)
> > > +{
> > > +     struct thermal_zone_device *tzd;
> > > +     int i;
> > > +
> > > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > +             tmdev->sensor[i].tmdev = tmdev;
> > > +             tmdev->sensor[i].id = i;
> > > +             tmdev->sensor[i].tzd =
> > > +                     devm_thermal_zone_of_sensor_register(tmdev->dev,
> > > +                                                          i,
> > > +                                                          &tmdev->sensor[i],
> > > +                                                          &ths_ops);
> > > +             if (IS_ERR(tmdev->sensor[i].tzd))
> > > +                     return PTR_ERR(tzd);
> > > +     }
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int sun8i_ths_probe(struct platform_device *pdev)
> > > +{
> > > +     struct ths_device *tmdev;
> > > +     struct device *dev = &pdev->dev;
> > > +     int i, ret;
> > > +
> > > +     tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
> > > +     if (!tmdev)
> > > +             return -ENOMEM;
> > > +
> > > +     tmdev->dev = dev;
> > > +     tmdev->chip = of_device_get_match_data(&pdev->dev);
> > > +     if (!tmdev->chip)
> > > +             return -EINVAL;
> > > +
> > > +     /*
> > > +      * Initialize wait_queue in advance, to avoid calling wake_up
> > > +      * before ths is registered in isr.
> > > +      */
> > > +     for (i = 0; i < tmdev->chip->sensor_num; i++)
> > > +             init_waitqueue_head(&tmdev->sensor[i].wait_queue);
> > > +
> > > +     platform_set_drvdata(pdev, tmdev);
> > > +
> > > +     ret = sun8i_ths_resource_init(tmdev);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     ret = tmdev->chip->init(tmdev);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     ret = sun8i_ths_register(tmdev);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     return ret;
> > > +}
> > > +
> > > +static int sun8i_ths_remove(struct platform_device *pdev)
> > > +{
> > > +     struct ths_device *tmdev = platform_get_drvdata(pdev);
> > > +
> > > +     clk_disable_unprepare(tmdev->bus_clk);
> > > +     reset_control_assert(tmdev->reset);
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int sun50i_thermal_init(struct ths_device *tmdev)
> > > +{
> > > +     int val;
> > > +
> > > +     /*
> > > +      * clkin = 24MHz
> > > +      * T acquire = clkin / (x + 1)
> > > +      *           = 20us
> > > +      */
> > > +     regmap_write(tmdev->regmap, SUN50I_THS_CTRL0,
> > > +                  SUN50I_THS_CTRL0_T_ACQ(479));
> > > +     /* average over 4 samples */
> > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC,
> > > +                  SUN50I_THS_FILTER_EN |
> > > +                  SUN50I_THS_FILTER_TYPE(1));
> > > +     /* period = (x + 1) * 4096 / clkin; ~10ms */
> > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_PC,
> > > +                  SUN50I_H6_THS_PC_TEMP_PERIOD(58));
> > > +     /* enable sensor */
> > > +     val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val);
> > > +     /* thermal data interrupt enable */
> > > +     val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_DIC, val);
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static const struct ths_thermal_chip sun50i_h6_ths = {
> > > +     .sensor_num = 2,
> > > +     .offset = -2794,
> > > +     .scale = -67,
> > > +     .ft_deviation = SUN50I_H6_FT_DEVIATION,
> > > +     .temp_calib_base = SUN50I_H6_THS_TEMP_CALIB,
> > > +     .temp_data_base = SUN50I_H6_THS_TEMP_DATA,
> > > +     .calibrate = sun50i_ths_calibrate,
> > > +     .init = sun50i_thermal_init,
> > > +     .irq_thread = sun50i_h6_irq_thread,
> > > +};
> > > +
> > > +static const struct of_device_id of_ths_match[] = {
> > > +     { .compatible = "allwinner,sun50i-h6-ths", .data = &sun50i_h6_ths },
> > > +     { /* sentinel */ },
> > > +};
> > > +MODULE_DEVICE_TABLE(of, of_ths_match);
> > > +
> > > +static struct platform_driver ths_driver = {
> > > +     .probe = sun8i_ths_probe,
> > > +     .remove = sun8i_ths_remove,
> > > +     .driver = {
> > > +             .name = "sun8i-thermal",
> > > +             .of_match_table = of_ths_match,
> > > +     },
> > > +};
> > > +module_platform_driver(ths_driver);
> > > +
> > > +MODULE_DESCRIPTION("Thermal sensor driver for Allwinner SOC");
> > > +MODULE_LICENSE("GPL v2");
> > > --
> > > 2.17.0
> > >
> > >
> > > _______________________________________________
> > > linux-arm-kernel mailing list
> > > [e-mail]
> > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Ondřej Jirman June 7, 2019, 5:18 p.m. UTC | #6

Hello Frank,

On Fri, Jun 07, 2019 at 09:50:08PM +0800, Frank Lee wrote:
> HI Ondřej,
> 
> 
> On Mon, May 27, 2019 at 10:25 PM Ondřej Jirman <[e-mail]> wrote:
> >
> > Hi Yangtao,
> >
> > On Sat, May 25, 2019 at 02:13:27PM -0400, Yangtao Li wrote:
> > > This patch adds the support for allwinner thermal sensor, within
> > > allwinner SoC. It will register sensors for thermal framework
> > > and use device tree to bind cooling device.
> > >
> > > Signed-off-by: Yangtao Li <[e-mail]>
> > > ---
> > >  MAINTAINERS                     |   7 +
> > >  drivers/thermal/Kconfig         |  14 +
> > >  drivers/thermal/Makefile        |   1 +
> > >  drivers/thermal/sun8i_thermal.c | 437 ++++++++++++++++++++++++++++++++
> > >  4 files changed, 459 insertions(+)
> > >  create mode 100644 drivers/thermal/sun8i_thermal.c
> > >
> > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > index 2336dd26ece4..d312f9eecf0d 100644
> > > --- a/MAINTAINERS
> > > +++ b/MAINTAINERS
> > > @@ -674,6 +674,13 @@ L:       [e-mail]
> > >  S:   Maintained
> > >  F:   drivers/crypto/sunxi-ss/
> > >
> > > +ALLWINNER THERMAL DRIVER
> > > +M:   Yangtao Li <[e-mail]>
> > > +L:   [e-mail]
> > > +S:   Maintained
> > > +F:   Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
> > > +F:   drivers/thermal/sun8i_thermal.c
> > > +
> > >  ALLWINNER VPU DRIVER
> > >  M:   Maxime Ripard <[e-mail]>
> > >  M:   Paul Kocialkowski <[e-mail]>
> > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> > > index 9966364a6deb..e5465053d66f 100644
> > > --- a/drivers/thermal/Kconfig
> > > +++ b/drivers/thermal/Kconfig
> > > @@ -262,6 +262,20 @@ config SPEAR_THERMAL
> > >         Enable this to plug the SPEAr thermal sensor driver into the Linux
> > >         thermal framework.
> > >
> > > +config SUN8I_THERMAL
> > > +     tristate "Allwinner sun8i thermal driver"
> > > +     depends on ARCH_SUNXI || COMPILE_TEST
> > > +     depends on HAS_IOMEM
> > > +     depends on NVMEM_SUNXI_SID
> > > +     depends on OF
> > > +     depends on RESET_CONTROLLER
> > > +     help
> > > +       Support for the sun8i thermal sensor driver into the Linux thermal
> > > +       framework.
> > > +
> > > +       To compile this driver as a module, choose M here: the
> > > +       module will be called sun8i-thermal.
> > > +
> > >  config ROCKCHIP_THERMAL
> > >       tristate "Rockchip thermal driver"
> > >       depends on ARCH_ROCKCHIP || COMPILE_TEST
> > > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> > > index 74a37c7f847a..fa6f8b206281 100644
> > > --- a/drivers/thermal/Makefile
> > > +++ b/drivers/thermal/Makefile
> > > @@ -31,6 +31,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
> > >  obj-y                                += broadcom/
> > >  obj-$(CONFIG_THERMAL_MMIO)           += thermal_mmio.o
> > >  obj-$(CONFIG_SPEAR_THERMAL)  += spear_thermal.o
> > > +obj-$(CONFIG_SUN8I_THERMAL)     += sun8i_thermal.o
> > >  obj-$(CONFIG_ROCKCHIP_THERMAL)       += rockchip_thermal.o
> > >  obj-$(CONFIG_RCAR_THERMAL)   += rcar_thermal.o
> > >  obj-$(CONFIG_RCAR_GEN3_THERMAL)      += rcar_gen3_thermal.o
> > > diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
> > > new file mode 100644
> > > index 000000000000..a9cc2197f4cb
> > > --- /dev/null
> > > +++ b/drivers/thermal/sun8i_thermal.c
> > > @@ -0,0 +1,437 @@
> > > +// SPDX-License-Identifier: GPL-2.0
> > > +/*
> > > + * Thermal sensor driver for Allwinner SOC
> > > + * Copyright (C) 2019 Yangtao Li
> > > + *
> > > + * Based on the work of Icenowy Zheng <[e-mail]>
> > > + * Based on the work of Ondrej Jirman <[e-mail]>
> > > + * Based on the work of Josef Gajdusek <[e-mail]>
> > > + */
> > > +
> > > +#include <linux/clk.h>
> > > +#include <linux/device.h>
> > > +#include <linux/interrupt.h>
> > > +#include <linux/wait.h>
> > > +#include <linux/module.h>
> > > +#include <linux/nvmem-consumer.h>
> > > +#include <linux/of_device.h>
> > > +#include <linux/platform_device.h>
> > > +#include <linux/regmap.h>
> > > +#include <linux/reset.h>
> > > +#include <linux/slab.h>
> > > +#include <linux/thermal.h>
> > > +
> > > +#define MAX_SENSOR_NUM       4
> > > +
> > > +#define FT_TEMP_MASK                         GENMASK(11, 0)
> > > +#define TEMP_CALIB_MASK                              GENMASK(11, 0)
> > > +#define TEMP_TO_REG                          672
> > > +#define CALIBRATE_DEFAULT                    0x800
> > > +
> > > +#define SUN50I_THS_CTRL0                     0x00
> > > +#define SUN50I_H6_THS_ENABLE                 0x04
> > > +#define SUN50I_H6_THS_PC                     0x08
> > > +#define SUN50I_H6_THS_DIC                    0x10
> > > +#define SUN50I_H6_THS_DIS                    0x20
> > > +#define SUN50I_H6_THS_MFC                    0x30
> > > +#define SUN50I_H6_THS_TEMP_CALIB             0xa0
> > > +#define SUN50I_H6_THS_TEMP_DATA                      0xc0
> > > +
> > > +#define SUN50I_THS_CTRL0_T_ACQ(x)            ((GENMASK(15, 0) & (x)) << 16)
> > > +#define SUN50I_THS_FILTER_EN                 BIT(2)
> > > +#define SUN50I_THS_FILTER_TYPE(x)            (GENMASK(1, 0) & (x))
> > > +#define SUN50I_H6_THS_PC_TEMP_PERIOD(x)              ((GENMASK(19, 0) & (x)) << 12)
> > > +#define SUN50I_H6_THS_DATA_IRQ_STS(x)                BIT(x)
> > > +
> > > +/* millidegree celsius */
> > > +#define SUN50I_H6_FT_DEVIATION                       7000
> > > +
> > > +struct ths_device;
> > > +
> > > +struct tsensor {
> > > +     struct ths_device               *tmdev;
> > > +     struct thermal_zone_device      *tzd;
> > > +     int                             id;
> > > +     wait_queue_head_t               wait_queue;
> > > +};
> > > +
> > > +struct ths_thermal_chip {
> > > +     int             sensor_num;
> > > +     int             offset;
> > > +     int             scale;
> > > +     int             ft_deviation;
> > > +     int             temp_calib_base;
> > > +     int             temp_data_base;
> > > +     int             (*calibrate)(struct ths_device *tmdev);
> > > +     int             (*init)(struct ths_device *tmdev);
> > > +     irqreturn_t     (*irq_thread)(int irq, void *data);
> > > +};
> > > +
> > > +struct ths_device {
> > > +     const struct ths_thermal_chip           *chip;
> > > +     struct device                           *dev;
> > > +     struct regmap                           *regmap;
> > > +     struct reset_control                    *reset;
> > > +     struct clk                              *bus_clk;
> > > +     struct tsensor                          sensor[MAX_SENSOR_NUM];
> > > +     int                                     data_ready;
> > > +};
> > > +
> > > +/* Temp Unit: millidegree Celsius */
> > > +static int sun8i_ths_reg2temp(struct ths_device *tmdev,
> > > +                           int reg)
> > > +{
> > > +     return (reg + tmdev->chip->offset) * tmdev->chip->scale;
> > > +}
> > > +
> > > +static int sun8i_ths_get_temp(void *data, int *temp)
> > > +{
> > > +     struct tsensor *s = data;
> > > +     struct ths_device *tmdev = s->tmdev;
> > > +     int val;
> > > +
> > > +     wait_event(s->wait_queue, tmdev->data_ready & BIT(s->id));
> > > +     tmdev->data_ready &= ~BIT(s->id);
> >
> > I've looked at thermal_core.c and it looks like that the proper way to handle
> > this situation is just returning -EAGAIN.
> 
> What we are doing now is to turn it into an interrupt-based program.
> Every time we use temperature data, we need to wait until new data is collected.

No you don't need to wait, and by waiting you're blocking a lot of tings in
thermal_core.c for no reason.

> >
> > See update_temperature() function in thermal_core.c.
> >
> > That will suppress the warning about failure to read thermal zone. Also
> > it's much simpler than this wait_queue stuff. No other thermal driver uses this
> > either. Also get_temp is called under thermal_list_lock mutex and that would
> > block cooling device registrations and god knows what else.
> 
> Since there is no valid temperature data, it cannot be blocked.

Sorry, I don't understand your meaning here. get_temp will block in
wait_event, and the above mentioned lock in tz code will be held during all this
time, until you get data_ready condition satisified sometimes in the future.

https://elixir.bootlin.com/linux/latest/source/drivers/thermal/thermal_core.c#L43

This will prevent all time zones in the system from being updated, regsitered,
etc, because it's a driver level lock.

Given that this is called from __thermal_cooling_device_register:

https://elixir.bootlin.com/linux/latest/source/drivers/thermal/thermal_core.c#L997

This will stop all other thermal zones from registering for no reason.

Just return -EAGAIN, as expected here:

https://elixir.bootlin.com/linux/latest/source/drivers/thermal/thermal_core.c#L431

And the driver will work in both interrupt driven and polled mode just fine,
without any warnings or delays or taking this lock for no reason for too long.

thank you and regards,
	o.

> MBR,
> Yangtao
> 
> >
> > Other than that, and what Maxime said, I don't see any more issues.
> >
> > thank you,
> >         o.
> >
> > > +     regmap_read(tmdev->regmap, tmdev->chip->temp_data_base +
> > > +                 0x4 * s->id, &val);
> > > +
> > > +     *temp = sun8i_ths_reg2temp(tmdev, val);
> > > +     /*
> > > +      * XX - According to the original sdk, there are some platforms(rarely)
> > > +      * that add a fixed offset value after calculating the temperature
> > > +      * value. We can't simply put it on the formula for calculating the
> > > +      * temperature above, because the formula for calculating the
> > > +      * temperature above is also used when the sensor is calibrated. If
> > > +      * do this, the correct calibration formula is hard to know.
> > > +      */
> > > +     if (tmdev->chip->ft_deviation)
> > > +             *temp += tmdev->chip->ft_deviation;
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static const struct thermal_zone_of_device_ops ths_ops = {
> > > +     .get_temp = sun8i_ths_get_temp,
> > > +};
> > > +
> > > +static const struct regmap_config config = {
> > > +     .reg_bits = 32,
> > > +     .val_bits = 32,
> > > +     .reg_stride = 4,
> > > +     .fast_io = true,
> > > +};
> > > +
> > > +static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
> > > +{
> > > +     wait_queue_head_t *data_wait;
> > > +     struct ths_device *tmdev = data;
> > > +     int i, state;
> > > +
> > > +     regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
> > > +
> > > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > +             data_wait = &tmdev->sensor[i].wait_queue;
> > > +
> > > +             if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
> > > +                     /* clear data irq pending */
> > > +                     regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
> > > +                                  SUN50I_H6_THS_DATA_IRQ_STS(i));
> > > +
> > > +                     tmdev->data_ready |= BIT(i);
> > > +                     wake_up(data_wait);
> > > +             }
> > > +     }
> > > +
> > > +     return IRQ_HANDLED;
> > > +}
> > > +
> > > +static int sun8i_ths_resource_init(struct ths_device *tmdev)
> > > +{
> > > +     struct device *dev = tmdev->dev;
> > > +     struct platform_device *pdev = to_platform_device(dev);
> > > +     struct resource *mem;
> > > +     void __iomem *base;
> > > +     int ret, irq;
> > > +
> > > +     mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > +     base = devm_ioremap_resource(dev, mem);
> > > +     if (IS_ERR(base))
> > > +             return PTR_ERR(base);
> > > +
> > > +     tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
> > > +     if (IS_ERR(tmdev->regmap))
> > > +             return PTR_ERR(tmdev->regmap);
> > > +
> > > +     tmdev->reset = devm_reset_control_get(dev, 0);
> > > +     if (IS_ERR(tmdev->reset))
> > > +             return PTR_ERR(tmdev->reset);
> > > +
> > > +     tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
> > > +     if (IS_ERR(tmdev->bus_clk))
> > > +             return PTR_ERR(tmdev->bus_clk);
> > > +
> > > +     irq = platform_get_irq(pdev, 0);
> > > +     if (irq < 0)
> > > +             return irq;
> > > +
> > > +     ret = devm_request_threaded_irq(dev, irq, NULL,
> > > +                                     tmdev->chip->irq_thread,
> > > +                                     IRQF_ONESHOT, "ths", tmdev);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     ret = reset_control_deassert(tmdev->reset);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     ret = clk_prepare_enable(tmdev->bus_clk);
> > > +     if (ret)
> > > +             goto assert_reset;
> > > +
> > > +     ret = tmdev->chip->calibrate(tmdev);
> > > +     if (ret)
> > > +             goto bus_disable;
> > > +
> > > +     return 0;
> > > +
> > > +bus_disable:
> > > +     clk_disable_unprepare(tmdev->bus_clk);
> > > +assert_reset:
> > > +     reset_control_assert(tmdev->reset);
> > > +
> > > +     return ret;
> > > +}
> > > +
> > > +static int sun50i_ths_calibrate(struct ths_device *tmdev)
> > > +{
> > > +     struct nvmem_cell *calcell;
> > > +     struct device *dev = tmdev->dev;
> > > +     u16 *caldata;
> > > +     size_t callen;
> > > +     int ft_temp;
> > > +     int i, ret = 0;
> > > +
> > > +     calcell = devm_nvmem_cell_get(dev, "calib");
> > > +     if (IS_ERR(calcell)) {
> > > +             if (PTR_ERR(calcell) == -EPROBE_DEFER)
> > > +                     return -EPROBE_DEFER;
> > > +             /*
> > > +              * Even if the external calibration data stored in sid is
> > > +              * not accessible, the THS hardware can still work, although
> > > +              * the data won't be so accurate.
> > > +              *
> > > +              * The default value of calibration register is 0x800 for
> > > +              * every sensor, and the calibration value is usually 0x7xx
> > > +              * or 0x8xx, so they won't be away from the default value
> > > +              * for a lot.
> > > +              *
> > > +              * So here we do not return error if the calibartion data is
> > > +              * not available, except the probe needs deferring.
> > > +              */
> > > +             goto out;
> > > +     }
> > > +
> > > +     caldata = nvmem_cell_read(calcell, &callen);
> > > +     if (IS_ERR(caldata)) {
> > > +             ret = PTR_ERR(caldata);
> > > +             goto out;
> > > +     }
> > > +
> > > +     if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) {
> > > +             ret = -EINVAL;
> > > +             goto out_free;
> > > +     }
> > > +
> > > +     /*
> > > +      * efuse layout:
> > > +      *
> > > +      *      0   11  16       32
> > > +      *      +-------+-------+-------+
> > > +      *      |temp|  |sensor0|sensor1|
> > > +      *      +-------+-------+-------+
> > > +      *
> > > +      * The calibration data on the H6 is the ambient temperature and
> > > +      * sensor values that are filled during the factory test stage.
> > > +      *
> > > +      * The unit of stored FT temperature is 0.1 degreee celusis.
> > > +      * Through the stored ambient temperature and the data read
> > > +      * by the sensor, after a certain calculation, the calibration
> > > +      * value to be compensated can be obtained.
> > > +      */
> > > +     ft_temp = caldata[0] & FT_TEMP_MASK;
> > > +
> > > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > +             int reg = (int)caldata[i + 1];
> > > +             int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
> > > +             int delta, cdata, calib_offest;
> > > +
> > > +             /*
> > > +              * To calculate the calibration value:
> > > +              *
> > > +              * X(in Celsius) = Ts - ft_temp
> > > +              * delta = X * 10000 / TEMP_TO_REG
> > > +              * cdata = CALIBRATE_DEFAULT - delta
> > > +              *
> > > +              * cdata: calibration value
> > > +              */
> > > +             delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
> > > +             cdata = CALIBRATE_DEFAULT - delta;
> > > +             if (cdata & ~TEMP_CALIB_MASK) {
> > > +                     /*
> > > +                      * Calibration value more than 12-bit, but calibration
> > > +                      * register is 12-bit. In this case, ths hardware can
> > > +                      * still work without calibration, although the data
> > > +                      * won't be so accurate.
> > > +                      */
> > > +                     dev_warn(dev, "sensor%d is not calibrated.\n", i);
> > > +
> > > +                     continue;
> > > +             }
> > > +
> > > +             calib_offest = tmdev->chip->temp_calib_base + (i / 2) * 0x4;
> > > +
> > > +             if (i % 2) {
> > > +                     int val;
> > > +
> > > +                     regmap_read(tmdev->regmap, calib_offest, &val);
> > > +                     val = (val & TEMP_CALIB_MASK) | (cdata << 16);
> > > +                     regmap_write(tmdev->regmap, calib_offest, val);
> > > +             } else {
> > > +                     regmap_write(tmdev->regmap, calib_offest, cdata);
> > > +             }
> > > +     }
> > > +
> > > +out_free:
> > > +     kfree(caldata);
> > > +out:
> > > +     return ret;
> > > +}
> > > +
> > > +static int sun8i_ths_register(struct ths_device *tmdev)
> > > +{
> > > +     struct thermal_zone_device *tzd;
> > > +     int i;
> > > +
> > > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > +             tmdev->sensor[i].tmdev = tmdev;
> > > +             tmdev->sensor[i].id = i;
> > > +             tmdev->sensor[i].tzd =
> > > +                     devm_thermal_zone_of_sensor_register(tmdev->dev,
> > > +                                                          i,
> > > +                                                          &tmdev->sensor[i],
> > > +                                                          &ths_ops);
> > > +             if (IS_ERR(tmdev->sensor[i].tzd))
> > > +                     return PTR_ERR(tzd);
> > > +     }
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int sun8i_ths_probe(struct platform_device *pdev)
> > > +{
> > > +     struct ths_device *tmdev;
> > > +     struct device *dev = &pdev->dev;
> > > +     int i, ret;
> > > +
> > > +     tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
> > > +     if (!tmdev)
> > > +             return -ENOMEM;
> > > +
> > > +     tmdev->dev = dev;
> > > +     tmdev->chip = of_device_get_match_data(&pdev->dev);
> > > +     if (!tmdev->chip)
> > > +             return -EINVAL;
> > > +
> > > +     /*
> > > +      * Initialize wait_queue in advance, to avoid calling wake_up
> > > +      * before ths is registered in isr.
> > > +      */
> > > +     for (i = 0; i < tmdev->chip->sensor_num; i++)
> > > +             init_waitqueue_head(&tmdev->sensor[i].wait_queue);
> > > +
> > > +     platform_set_drvdata(pdev, tmdev);
> > > +
> > > +     ret = sun8i_ths_resource_init(tmdev);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     ret = tmdev->chip->init(tmdev);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     ret = sun8i_ths_register(tmdev);
> > > +     if (ret)
> > > +             return ret;
> > > +
> > > +     return ret;
> > > +}
> > > +
> > > +static int sun8i_ths_remove(struct platform_device *pdev)
> > > +{
> > > +     struct ths_device *tmdev = platform_get_drvdata(pdev);
> > > +
> > > +     clk_disable_unprepare(tmdev->bus_clk);
> > > +     reset_control_assert(tmdev->reset);
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static int sun50i_thermal_init(struct ths_device *tmdev)
> > > +{
> > > +     int val;
> > > +
> > > +     /*
> > > +      * clkin = 24MHz
> > > +      * T acquire = clkin / (x + 1)
> > > +      *           = 20us
> > > +      */
> > > +     regmap_write(tmdev->regmap, SUN50I_THS_CTRL0,
> > > +                  SUN50I_THS_CTRL0_T_ACQ(479));
> > > +     /* average over 4 samples */
> > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC,
> > > +                  SUN50I_THS_FILTER_EN |
> > > +                  SUN50I_THS_FILTER_TYPE(1));
> > > +     /* period = (x + 1) * 4096 / clkin; ~10ms */
> > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_PC,
> > > +                  SUN50I_H6_THS_PC_TEMP_PERIOD(58));
> > > +     /* enable sensor */
> > > +     val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val);
> > > +     /* thermal data interrupt enable */
> > > +     val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_DIC, val);
> > > +
> > > +     return 0;
> > > +}
> > > +
> > > +static const struct ths_thermal_chip sun50i_h6_ths = {
> > > +     .sensor_num = 2,
> > > +     .offset = -2794,
> > > +     .scale = -67,
> > > +     .ft_deviation = SUN50I_H6_FT_DEVIATION,
> > > +     .temp_calib_base = SUN50I_H6_THS_TEMP_CALIB,
> > > +     .temp_data_base = SUN50I_H6_THS_TEMP_DATA,
> > > +     .calibrate = sun50i_ths_calibrate,
> > > +     .init = sun50i_thermal_init,
> > > +     .irq_thread = sun50i_h6_irq_thread,
> > > +};
> > > +
> > > +static const struct of_device_id of_ths_match[] = {
> > > +     { .compatible = "allwinner,sun50i-h6-ths", .data = &sun50i_h6_ths },
> > > +     { /* sentinel */ },
> > > +};
> > > +MODULE_DEVICE_TABLE(of, of_ths_match);
> > > +
> > > +static struct platform_driver ths_driver = {
> > > +     .probe = sun8i_ths_probe,
> > > +     .remove = sun8i_ths_remove,
> > > +     .driver = {
> > > +             .name = "sun8i-thermal",
> > > +             .of_match_table = of_ths_match,
> > > +     },
> > > +};
> > > +module_platform_driver(ths_driver);
> > > +
> > > +MODULE_DESCRIPTION("Thermal sensor driver for Allwinner SOC");
> > > +MODULE_LICENSE("GPL v2");
> > > --
> > > 2.17.0
> > >
> > >
> > > _______________________________________________
> > > linux-arm-kernel mailing list
> > > [e-mail]
> > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> 
> _______________________________________________
> linux-arm-kernel mailing list
> [e-mail]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Ondřej Jirman June 7, 2019, 5:25 p.m. UTC | #7

On Fri, Jun 07, 2019 at 07:18:21PM +0200, verejna wrote:
> Hello Frank,
> 
> On Fri, Jun 07, 2019 at 09:50:08PM +0800, Frank Lee wrote:
> > HI Ondřej,
> > 
> > 
> > On Mon, May 27, 2019 at 10:25 PM Ondřej Jirman <[e-mail]> wrote:
> > >
> > > Hi Yangtao,
> > >
> > > On Sat, May 25, 2019 at 02:13:27PM -0400, Yangtao Li wrote:
> > > > This patch adds the support for allwinner thermal sensor, within
> > > > allwinner SoC. It will register sensors for thermal framework
> > > > and use device tree to bind cooling device.
> > > >
> > > > Signed-off-by: Yangtao Li <[e-mail]>
> > > > ---
> > > >  MAINTAINERS                     |   7 +
> > > >  drivers/thermal/Kconfig         |  14 +
> > > >  drivers/thermal/Makefile        |   1 +
> > > >  drivers/thermal/sun8i_thermal.c | 437 ++++++++++++++++++++++++++++++++
> > > >  4 files changed, 459 insertions(+)
> > > >  create mode 100644 drivers/thermal/sun8i_thermal.c
> > > >
> > > > diff --git a/MAINTAINERS b/MAINTAINERS
> > > > index 2336dd26ece4..d312f9eecf0d 100644
> > > > --- a/MAINTAINERS
> > > > +++ b/MAINTAINERS
> > > > @@ -674,6 +674,13 @@ L:       [e-mail]
> > > >  S:   Maintained
> > > >  F:   drivers/crypto/sunxi-ss/
> > > >
> > > > +ALLWINNER THERMAL DRIVER
> > > > +M:   Yangtao Li <[e-mail]>
> > > > +L:   [e-mail]
> > > > +S:   Maintained
> > > > +F:   Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
> > > > +F:   drivers/thermal/sun8i_thermal.c
> > > > +
> > > >  ALLWINNER VPU DRIVER
> > > >  M:   Maxime Ripard <[e-mail]>
> > > >  M:   Paul Kocialkowski <[e-mail]>
> > > > diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> > > > index 9966364a6deb..e5465053d66f 100644
> > > > --- a/drivers/thermal/Kconfig
> > > > +++ b/drivers/thermal/Kconfig
> > > > @@ -262,6 +262,20 @@ config SPEAR_THERMAL
> > > >         Enable this to plug the SPEAr thermal sensor driver into the Linux
> > > >         thermal framework.
> > > >
> > > > +config SUN8I_THERMAL
> > > > +     tristate "Allwinner sun8i thermal driver"
> > > > +     depends on ARCH_SUNXI || COMPILE_TEST
> > > > +     depends on HAS_IOMEM
> > > > +     depends on NVMEM_SUNXI_SID
> > > > +     depends on OF
> > > > +     depends on RESET_CONTROLLER
> > > > +     help
> > > > +       Support for the sun8i thermal sensor driver into the Linux thermal
> > > > +       framework.
> > > > +
> > > > +       To compile this driver as a module, choose M here: the
> > > > +       module will be called sun8i-thermal.
> > > > +
> > > >  config ROCKCHIP_THERMAL
> > > >       tristate "Rockchip thermal driver"
> > > >       depends on ARCH_ROCKCHIP || COMPILE_TEST
> > > > diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> > > > index 74a37c7f847a..fa6f8b206281 100644
> > > > --- a/drivers/thermal/Makefile
> > > > +++ b/drivers/thermal/Makefile
> > > > @@ -31,6 +31,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
> > > >  obj-y                                += broadcom/
> > > >  obj-$(CONFIG_THERMAL_MMIO)           += thermal_mmio.o
> > > >  obj-$(CONFIG_SPEAR_THERMAL)  += spear_thermal.o
> > > > +obj-$(CONFIG_SUN8I_THERMAL)     += sun8i_thermal.o
> > > >  obj-$(CONFIG_ROCKCHIP_THERMAL)       += rockchip_thermal.o
> > > >  obj-$(CONFIG_RCAR_THERMAL)   += rcar_thermal.o
> > > >  obj-$(CONFIG_RCAR_GEN3_THERMAL)      += rcar_gen3_thermal.o
> > > > diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
> > > > new file mode 100644
> > > > index 000000000000..a9cc2197f4cb
> > > > --- /dev/null
> > > > +++ b/drivers/thermal/sun8i_thermal.c
> > > > @@ -0,0 +1,437 @@
> > > > +// SPDX-License-Identifier: GPL-2.0
> > > > +/*
> > > > + * Thermal sensor driver for Allwinner SOC
> > > > + * Copyright (C) 2019 Yangtao Li
> > > > + *
> > > > + * Based on the work of Icenowy Zheng <[e-mail]>
> > > > + * Based on the work of Ondrej Jirman <[e-mail]>
> > > > + * Based on the work of Josef Gajdusek <[e-mail]>
> > > > + */
> > > > +
> > > > +#include <linux/clk.h>
> > > > +#include <linux/device.h>
> > > > +#include <linux/interrupt.h>
> > > > +#include <linux/wait.h>
> > > > +#include <linux/module.h>
> > > > +#include <linux/nvmem-consumer.h>
> > > > +#include <linux/of_device.h>
> > > > +#include <linux/platform_device.h>
> > > > +#include <linux/regmap.h>
> > > > +#include <linux/reset.h>
> > > > +#include <linux/slab.h>
> > > > +#include <linux/thermal.h>
> > > > +
> > > > +#define MAX_SENSOR_NUM       4
> > > > +
> > > > +#define FT_TEMP_MASK                         GENMASK(11, 0)
> > > > +#define TEMP_CALIB_MASK                              GENMASK(11, 0)
> > > > +#define TEMP_TO_REG                          672
> > > > +#define CALIBRATE_DEFAULT                    0x800
> > > > +
> > > > +#define SUN50I_THS_CTRL0                     0x00
> > > > +#define SUN50I_H6_THS_ENABLE                 0x04
> > > > +#define SUN50I_H6_THS_PC                     0x08
> > > > +#define SUN50I_H6_THS_DIC                    0x10
> > > > +#define SUN50I_H6_THS_DIS                    0x20
> > > > +#define SUN50I_H6_THS_MFC                    0x30
> > > > +#define SUN50I_H6_THS_TEMP_CALIB             0xa0
> > > > +#define SUN50I_H6_THS_TEMP_DATA                      0xc0
> > > > +
> > > > +#define SUN50I_THS_CTRL0_T_ACQ(x)            ((GENMASK(15, 0) & (x)) << 16)
> > > > +#define SUN50I_THS_FILTER_EN                 BIT(2)
> > > > +#define SUN50I_THS_FILTER_TYPE(x)            (GENMASK(1, 0) & (x))
> > > > +#define SUN50I_H6_THS_PC_TEMP_PERIOD(x)              ((GENMASK(19, 0) & (x)) << 12)
> > > > +#define SUN50I_H6_THS_DATA_IRQ_STS(x)                BIT(x)
> > > > +
> > > > +/* millidegree celsius */
> > > > +#define SUN50I_H6_FT_DEVIATION                       7000
> > > > +
> > > > +struct ths_device;
> > > > +
> > > > +struct tsensor {
> > > > +     struct ths_device               *tmdev;
> > > > +     struct thermal_zone_device      *tzd;
> > > > +     int                             id;
> > > > +     wait_queue_head_t               wait_queue;
> > > > +};
> > > > +
> > > > +struct ths_thermal_chip {
> > > > +     int             sensor_num;
> > > > +     int             offset;
> > > > +     int             scale;
> > > > +     int             ft_deviation;
> > > > +     int             temp_calib_base;
> > > > +     int             temp_data_base;
> > > > +     int             (*calibrate)(struct ths_device *tmdev);
> > > > +     int             (*init)(struct ths_device *tmdev);
> > > > +     irqreturn_t     (*irq_thread)(int irq, void *data);
> > > > +};
> > > > +
> > > > +struct ths_device {
> > > > +     const struct ths_thermal_chip           *chip;
> > > > +     struct device                           *dev;
> > > > +     struct regmap                           *regmap;
> > > > +     struct reset_control                    *reset;
> > > > +     struct clk                              *bus_clk;
> > > > +     struct tsensor                          sensor[MAX_SENSOR_NUM];
> > > > +     int                                     data_ready;
> > > > +};
> > > > +
> > > > +/* Temp Unit: millidegree Celsius */
> > > > +static int sun8i_ths_reg2temp(struct ths_device *tmdev,
> > > > +                           int reg)
> > > > +{
> > > > +     return (reg + tmdev->chip->offset) * tmdev->chip->scale;
> > > > +}
> > > > +
> > > > +static int sun8i_ths_get_temp(void *data, int *temp)
> > > > +{
> > > > +     struct tsensor *s = data;
> > > > +     struct ths_device *tmdev = s->tmdev;
> > > > +     int val;
> > > > +
> > > > +     wait_event(s->wait_queue, tmdev->data_ready & BIT(s->id));
> > > > +     tmdev->data_ready &= ~BIT(s->id);
> > >
> > > I've looked at thermal_core.c and it looks like that the proper way to handle
> > > this situation is just returning -EAGAIN.
> > 
> > What we are doing now is to turn it into an interrupt-based program.
> > Every time we use temperature data, we need to wait until new data is collected.
> 
> No you don't need to wait, and by waiting you're blocking a lot of tings in
> thermal_core.c for no reason.
> 
> > >
> > > See update_temperature() function in thermal_core.c.
> > >
> > > That will suppress the warning about failure to read thermal zone. Also
> > > it's much simpler than this wait_queue stuff. No other thermal driver uses this
> > > either. Also get_temp is called under thermal_list_lock mutex and that would
> > > block cooling device registrations and god knows what else.
> > 
> > Since there is no valid temperature data, it cannot be blocked.
> 
> Sorry, I don't understand your meaning here. get_temp will block in
> wait_event, and the above mentioned lock in tz code will be held during all this
> time, until you get data_ready condition satisified sometimes in the future.
> 
> https://elixir.bootlin.com/linux/latest/source/drivers/thermal/thermal_core.c#L43
> 
> This will prevent all time zones in the system from being updated, regsitered,
> etc, because it's a driver level lock.
> 
> Given that this is called from __thermal_cooling_device_register:
> 
> https://elixir.bootlin.com/linux/latest/source/drivers/thermal/thermal_core.c#L997

Other effect I guess, since this is a driver registration function is that this
will end up blocking boot on the thermal_list_lock if you have more than
1 cooling device until you get the first sample, which is not really acceptable.

regards,
	o.

> This will stop all other thermal zones from registering for no reason.
> 
> Just return -EAGAIN, as expected here:
> 
> https://elixir.bootlin.com/linux/latest/source/drivers/thermal/thermal_core.c#L431
> 
> And the driver will work in both interrupt driven and polled mode just fine,
> without any warnings or delays or taking this lock for no reason for too long.
> 
> thank you and regards,
> 	o.
> 
> > MBR,
> > Yangtao
> > 
> > >
> > > Other than that, and what Maxime said, I don't see any more issues.
> > >
> > > thank you,
> > >         o.
> > >
> > > > +     regmap_read(tmdev->regmap, tmdev->chip->temp_data_base +
> > > > +                 0x4 * s->id, &val);
> > > > +
> > > > +     *temp = sun8i_ths_reg2temp(tmdev, val);
> > > > +     /*
> > > > +      * XX - According to the original sdk, there are some platforms(rarely)
> > > > +      * that add a fixed offset value after calculating the temperature
> > > > +      * value. We can't simply put it on the formula for calculating the
> > > > +      * temperature above, because the formula for calculating the
> > > > +      * temperature above is also used when the sensor is calibrated. If
> > > > +      * do this, the correct calibration formula is hard to know.
> > > > +      */
> > > > +     if (tmdev->chip->ft_deviation)
> > > > +             *temp += tmdev->chip->ft_deviation;
> > > > +
> > > > +     return 0;
> > > > +}
> > > > +
> > > > +static const struct thermal_zone_of_device_ops ths_ops = {
> > > > +     .get_temp = sun8i_ths_get_temp,
> > > > +};
> > > > +
> > > > +static const struct regmap_config config = {
> > > > +     .reg_bits = 32,
> > > > +     .val_bits = 32,
> > > > +     .reg_stride = 4,
> > > > +     .fast_io = true,
> > > > +};
> > > > +
> > > > +static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
> > > > +{
> > > > +     wait_queue_head_t *data_wait;
> > > > +     struct ths_device *tmdev = data;
> > > > +     int i, state;
> > > > +
> > > > +     regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
> > > > +
> > > > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > > +             data_wait = &tmdev->sensor[i].wait_queue;
> > > > +
> > > > +             if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
> > > > +                     /* clear data irq pending */
> > > > +                     regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
> > > > +                                  SUN50I_H6_THS_DATA_IRQ_STS(i));
> > > > +
> > > > +                     tmdev->data_ready |= BIT(i);
> > > > +                     wake_up(data_wait);
> > > > +             }
> > > > +     }
> > > > +
> > > > +     return IRQ_HANDLED;
> > > > +}
> > > > +
> > > > +static int sun8i_ths_resource_init(struct ths_device *tmdev)
> > > > +{
> > > > +     struct device *dev = tmdev->dev;
> > > > +     struct platform_device *pdev = to_platform_device(dev);
> > > > +     struct resource *mem;
> > > > +     void __iomem *base;
> > > > +     int ret, irq;
> > > > +
> > > > +     mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > > > +     base = devm_ioremap_resource(dev, mem);
> > > > +     if (IS_ERR(base))
> > > > +             return PTR_ERR(base);
> > > > +
> > > > +     tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
> > > > +     if (IS_ERR(tmdev->regmap))
> > > > +             return PTR_ERR(tmdev->regmap);
> > > > +
> > > > +     tmdev->reset = devm_reset_control_get(dev, 0);
> > > > +     if (IS_ERR(tmdev->reset))
> > > > +             return PTR_ERR(tmdev->reset);
> > > > +
> > > > +     tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
> > > > +     if (IS_ERR(tmdev->bus_clk))
> > > > +             return PTR_ERR(tmdev->bus_clk);
> > > > +
> > > > +     irq = platform_get_irq(pdev, 0);
> > > > +     if (irq < 0)
> > > > +             return irq;
> > > > +
> > > > +     ret = devm_request_threaded_irq(dev, irq, NULL,
> > > > +                                     tmdev->chip->irq_thread,
> > > > +                                     IRQF_ONESHOT, "ths", tmdev);
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     ret = reset_control_deassert(tmdev->reset);
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     ret = clk_prepare_enable(tmdev->bus_clk);
> > > > +     if (ret)
> > > > +             goto assert_reset;
> > > > +
> > > > +     ret = tmdev->chip->calibrate(tmdev);
> > > > +     if (ret)
> > > > +             goto bus_disable;
> > > > +
> > > > +     return 0;
> > > > +
> > > > +bus_disable:
> > > > +     clk_disable_unprepare(tmdev->bus_clk);
> > > > +assert_reset:
> > > > +     reset_control_assert(tmdev->reset);
> > > > +
> > > > +     return ret;
> > > > +}
> > > > +
> > > > +static int sun50i_ths_calibrate(struct ths_device *tmdev)
> > > > +{
> > > > +     struct nvmem_cell *calcell;
> > > > +     struct device *dev = tmdev->dev;
> > > > +     u16 *caldata;
> > > > +     size_t callen;
> > > > +     int ft_temp;
> > > > +     int i, ret = 0;
> > > > +
> > > > +     calcell = devm_nvmem_cell_get(dev, "calib");
> > > > +     if (IS_ERR(calcell)) {
> > > > +             if (PTR_ERR(calcell) == -EPROBE_DEFER)
> > > > +                     return -EPROBE_DEFER;
> > > > +             /*
> > > > +              * Even if the external calibration data stored in sid is
> > > > +              * not accessible, the THS hardware can still work, although
> > > > +              * the data won't be so accurate.
> > > > +              *
> > > > +              * The default value of calibration register is 0x800 for
> > > > +              * every sensor, and the calibration value is usually 0x7xx
> > > > +              * or 0x8xx, so they won't be away from the default value
> > > > +              * for a lot.
> > > > +              *
> > > > +              * So here we do not return error if the calibartion data is
> > > > +              * not available, except the probe needs deferring.
> > > > +              */
> > > > +             goto out;
> > > > +     }
> > > > +
> > > > +     caldata = nvmem_cell_read(calcell, &callen);
> > > > +     if (IS_ERR(caldata)) {
> > > > +             ret = PTR_ERR(caldata);
> > > > +             goto out;
> > > > +     }
> > > > +
> > > > +     if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) {
> > > > +             ret = -EINVAL;
> > > > +             goto out_free;
> > > > +     }
> > > > +
> > > > +     /*
> > > > +      * efuse layout:
> > > > +      *
> > > > +      *      0   11  16       32
> > > > +      *      +-------+-------+-------+
> > > > +      *      |temp|  |sensor0|sensor1|
> > > > +      *      +-------+-------+-------+
> > > > +      *
> > > > +      * The calibration data on the H6 is the ambient temperature and
> > > > +      * sensor values that are filled during the factory test stage.
> > > > +      *
> > > > +      * The unit of stored FT temperature is 0.1 degreee celusis.
> > > > +      * Through the stored ambient temperature and the data read
> > > > +      * by the sensor, after a certain calculation, the calibration
> > > > +      * value to be compensated can be obtained.
> > > > +      */
> > > > +     ft_temp = caldata[0] & FT_TEMP_MASK;
> > > > +
> > > > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > > +             int reg = (int)caldata[i + 1];
> > > > +             int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
> > > > +             int delta, cdata, calib_offest;
> > > > +
> > > > +             /*
> > > > +              * To calculate the calibration value:
> > > > +              *
> > > > +              * X(in Celsius) = Ts - ft_temp
> > > > +              * delta = X * 10000 / TEMP_TO_REG
> > > > +              * cdata = CALIBRATE_DEFAULT - delta
> > > > +              *
> > > > +              * cdata: calibration value
> > > > +              */
> > > > +             delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
> > > > +             cdata = CALIBRATE_DEFAULT - delta;
> > > > +             if (cdata & ~TEMP_CALIB_MASK) {
> > > > +                     /*
> > > > +                      * Calibration value more than 12-bit, but calibration
> > > > +                      * register is 12-bit. In this case, ths hardware can
> > > > +                      * still work without calibration, although the data
> > > > +                      * won't be so accurate.
> > > > +                      */
> > > > +                     dev_warn(dev, "sensor%d is not calibrated.\n", i);
> > > > +
> > > > +                     continue;
> > > > +             }
> > > > +
> > > > +             calib_offest = tmdev->chip->temp_calib_base + (i / 2) * 0x4;
> > > > +
> > > > +             if (i % 2) {
> > > > +                     int val;
> > > > +
> > > > +                     regmap_read(tmdev->regmap, calib_offest, &val);
> > > > +                     val = (val & TEMP_CALIB_MASK) | (cdata << 16);
> > > > +                     regmap_write(tmdev->regmap, calib_offest, val);
> > > > +             } else {
> > > > +                     regmap_write(tmdev->regmap, calib_offest, cdata);
> > > > +             }
> > > > +     }
> > > > +
> > > > +out_free:
> > > > +     kfree(caldata);
> > > > +out:
> > > > +     return ret;
> > > > +}
> > > > +
> > > > +static int sun8i_ths_register(struct ths_device *tmdev)
> > > > +{
> > > > +     struct thermal_zone_device *tzd;
> > > > +     int i;
> > > > +
> > > > +     for (i = 0; i < tmdev->chip->sensor_num; i++) {
> > > > +             tmdev->sensor[i].tmdev = tmdev;
> > > > +             tmdev->sensor[i].id = i;
> > > > +             tmdev->sensor[i].tzd =
> > > > +                     devm_thermal_zone_of_sensor_register(tmdev->dev,
> > > > +                                                          i,
> > > > +                                                          &tmdev->sensor[i],
> > > > +                                                          &ths_ops);
> > > > +             if (IS_ERR(tmdev->sensor[i].tzd))
> > > > +                     return PTR_ERR(tzd);
> > > > +     }
> > > > +
> > > > +     return 0;
> > > > +}
> > > > +
> > > > +static int sun8i_ths_probe(struct platform_device *pdev)
> > > > +{
> > > > +     struct ths_device *tmdev;
> > > > +     struct device *dev = &pdev->dev;
> > > > +     int i, ret;
> > > > +
> > > > +     tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
> > > > +     if (!tmdev)
> > > > +             return -ENOMEM;
> > > > +
> > > > +     tmdev->dev = dev;
> > > > +     tmdev->chip = of_device_get_match_data(&pdev->dev);
> > > > +     if (!tmdev->chip)
> > > > +             return -EINVAL;
> > > > +
> > > > +     /*
> > > > +      * Initialize wait_queue in advance, to avoid calling wake_up
> > > > +      * before ths is registered in isr.
> > > > +      */
> > > > +     for (i = 0; i < tmdev->chip->sensor_num; i++)
> > > > +             init_waitqueue_head(&tmdev->sensor[i].wait_queue);
> > > > +
> > > > +     platform_set_drvdata(pdev, tmdev);
> > > > +
> > > > +     ret = sun8i_ths_resource_init(tmdev);
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     ret = tmdev->chip->init(tmdev);
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     ret = sun8i_ths_register(tmdev);
> > > > +     if (ret)
> > > > +             return ret;
> > > > +
> > > > +     return ret;
> > > > +}
> > > > +
> > > > +static int sun8i_ths_remove(struct platform_device *pdev)
> > > > +{
> > > > +     struct ths_device *tmdev = platform_get_drvdata(pdev);
> > > > +
> > > > +     clk_disable_unprepare(tmdev->bus_clk);
> > > > +     reset_control_assert(tmdev->reset);
> > > > +
> > > > +     return 0;
> > > > +}
> > > > +
> > > > +static int sun50i_thermal_init(struct ths_device *tmdev)
> > > > +{
> > > > +     int val;
> > > > +
> > > > +     /*
> > > > +      * clkin = 24MHz
> > > > +      * T acquire = clkin / (x + 1)
> > > > +      *           = 20us
> > > > +      */
> > > > +     regmap_write(tmdev->regmap, SUN50I_THS_CTRL0,
> > > > +                  SUN50I_THS_CTRL0_T_ACQ(479));
> > > > +     /* average over 4 samples */
> > > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC,
> > > > +                  SUN50I_THS_FILTER_EN |
> > > > +                  SUN50I_THS_FILTER_TYPE(1));
> > > > +     /* period = (x + 1) * 4096 / clkin; ~10ms */
> > > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_PC,
> > > > +                  SUN50I_H6_THS_PC_TEMP_PERIOD(58));
> > > > +     /* enable sensor */
> > > > +     val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> > > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val);
> > > > +     /* thermal data interrupt enable */
> > > > +     val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> > > > +     regmap_write(tmdev->regmap, SUN50I_H6_THS_DIC, val);
> > > > +
> > > > +     return 0;
> > > > +}
> > > > +
> > > > +static const struct ths_thermal_chip sun50i_h6_ths = {
> > > > +     .sensor_num = 2,
> > > > +     .offset = -2794,
> > > > +     .scale = -67,
> > > > +     .ft_deviation = SUN50I_H6_FT_DEVIATION,
> > > > +     .temp_calib_base = SUN50I_H6_THS_TEMP_CALIB,
> > > > +     .temp_data_base = SUN50I_H6_THS_TEMP_DATA,
> > > > +     .calibrate = sun50i_ths_calibrate,
> > > > +     .init = sun50i_thermal_init,
> > > > +     .irq_thread = sun50i_h6_irq_thread,
> > > > +};
> > > > +
> > > > +static const struct of_device_id of_ths_match[] = {
> > > > +     { .compatible = "allwinner,sun50i-h6-ths", .data = &sun50i_h6_ths },
> > > > +     { /* sentinel */ },
> > > > +};
> > > > +MODULE_DEVICE_TABLE(of, of_ths_match);
> > > > +
> > > > +static struct platform_driver ths_driver = {
> > > > +     .probe = sun8i_ths_probe,
> > > > +     .remove = sun8i_ths_remove,
> > > > +     .driver = {
> > > > +             .name = "sun8i-thermal",
> > > > +             .of_match_table = of_ths_match,
> > > > +     },
> > > > +};
> > > > +module_platform_driver(ths_driver);
> > > > +
> > > > +MODULE_DESCRIPTION("Thermal sensor driver for Allwinner SOC");
> > > > +MODULE_LICENSE("GPL v2");
> > > > --
> > > > 2.17.0
> > > >
> > > >
> > > > _______________________________________________
> > > > linux-arm-kernel mailing list
> > > > [e-mail]
> > > > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> > 
> > _______________________________________________
> > linux-arm-kernel mailing list
> > [e-mail]
> > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
> 
> _______________________________________________
> linux-arm-kernel mailing list
> [e-mail]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Vasily Khoruzhick June 10, 2019, 11:29 p.m. UTC | #8

On Sat, May 25, 2019 at 11:17 AM Yangtao Li <[e-mail]> wrote:
>
> This patch adds the support for allwinner thermal sensor, within
> allwinner SoC. It will register sensors for thermal framework
> and use device tree to bind cooling device.

Hi Yangtao,

Any plans on v4 of this series?

> Signed-off-by: Yangtao Li <[e-mail]>
> ---
>  MAINTAINERS                     |   7 +
>  drivers/thermal/Kconfig         |  14 +
>  drivers/thermal/Makefile        |   1 +
>  drivers/thermal/sun8i_thermal.c | 437 ++++++++++++++++++++++++++++++++
>  4 files changed, 459 insertions(+)
>  create mode 100644 drivers/thermal/sun8i_thermal.c
>
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 2336dd26ece4..d312f9eecf0d 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -674,6 +674,13 @@ L: [e-mail]
>  S:     Maintained
>  F:     drivers/crypto/sunxi-ss/
>
> +ALLWINNER THERMAL DRIVER
> +M:     Yangtao Li <[e-mail]>
> +L:     [e-mail]
> +S:     Maintained
> +F:     Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
> +F:     drivers/thermal/sun8i_thermal.c
> +
>  ALLWINNER VPU DRIVER
>  M:     Maxime Ripard <[e-mail]>
>  M:     Paul Kocialkowski <[e-mail]>
> diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
> index 9966364a6deb..e5465053d66f 100644
> --- a/drivers/thermal/Kconfig
> +++ b/drivers/thermal/Kconfig
> @@ -262,6 +262,20 @@ config SPEAR_THERMAL
>           Enable this to plug the SPEAr thermal sensor driver into the Linux
>           thermal framework.
>
> +config SUN8I_THERMAL
> +       tristate "Allwinner sun8i thermal driver"
> +       depends on ARCH_SUNXI || COMPILE_TEST
> +       depends on HAS_IOMEM
> +       depends on NVMEM_SUNXI_SID
> +       depends on OF
> +       depends on RESET_CONTROLLER
> +       help
> +         Support for the sun8i thermal sensor driver into the Linux thermal
> +         framework.
> +
> +         To compile this driver as a module, choose M here: the
> +         module will be called sun8i-thermal.
> +
>  config ROCKCHIP_THERMAL
>         tristate "Rockchip thermal driver"
>         depends on ARCH_ROCKCHIP || COMPILE_TEST
> diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
> index 74a37c7f847a..fa6f8b206281 100644
> --- a/drivers/thermal/Makefile
> +++ b/drivers/thermal/Makefile
> @@ -31,6 +31,7 @@ thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
>  obj-y                          += broadcom/
>  obj-$(CONFIG_THERMAL_MMIO)             += thermal_mmio.o
>  obj-$(CONFIG_SPEAR_THERMAL)    += spear_thermal.o
> +obj-$(CONFIG_SUN8I_THERMAL)     += sun8i_thermal.o
>  obj-$(CONFIG_ROCKCHIP_THERMAL) += rockchip_thermal.o
>  obj-$(CONFIG_RCAR_THERMAL)     += rcar_thermal.o
>  obj-$(CONFIG_RCAR_GEN3_THERMAL)        += rcar_gen3_thermal.o
> diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
> new file mode 100644
> index 000000000000..a9cc2197f4cb
> --- /dev/null
> +++ b/drivers/thermal/sun8i_thermal.c
> @@ -0,0 +1,437 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * Thermal sensor driver for Allwinner SOC
> + * Copyright (C) 2019 Yangtao Li
> + *
> + * Based on the work of Icenowy Zheng <[e-mail]>
> + * Based on the work of Ondrej Jirman <[e-mail]>
> + * Based on the work of Josef Gajdusek <[e-mail]>
> + */
> +
> +#include <linux/clk.h>
> +#include <linux/device.h>
> +#include <linux/interrupt.h>
> +#include <linux/wait.h>
> +#include <linux/module.h>
> +#include <linux/nvmem-consumer.h>
> +#include <linux/of_device.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>
> +#include <linux/reset.h>
> +#include <linux/slab.h>
> +#include <linux/thermal.h>
> +
> +#define MAX_SENSOR_NUM 4
> +
> +#define FT_TEMP_MASK                           GENMASK(11, 0)
> +#define TEMP_CALIB_MASK                                GENMASK(11, 0)
> +#define TEMP_TO_REG                            672
> +#define CALIBRATE_DEFAULT                      0x800
> +
> +#define SUN50I_THS_CTRL0                       0x00
> +#define SUN50I_H6_THS_ENABLE                   0x04
> +#define SUN50I_H6_THS_PC                       0x08
> +#define SUN50I_H6_THS_DIC                      0x10
> +#define SUN50I_H6_THS_DIS                      0x20
> +#define SUN50I_H6_THS_MFC                      0x30
> +#define SUN50I_H6_THS_TEMP_CALIB               0xa0
> +#define SUN50I_H6_THS_TEMP_DATA                        0xc0
> +
> +#define SUN50I_THS_CTRL0_T_ACQ(x)              ((GENMASK(15, 0) & (x)) << 16)
> +#define SUN50I_THS_FILTER_EN                   BIT(2)
> +#define SUN50I_THS_FILTER_TYPE(x)              (GENMASK(1, 0) & (x))
> +#define SUN50I_H6_THS_PC_TEMP_PERIOD(x)                ((GENMASK(19, 0) & (x)) << 12)
> +#define SUN50I_H6_THS_DATA_IRQ_STS(x)          BIT(x)
> +
> +/* millidegree celsius */
> +#define SUN50I_H6_FT_DEVIATION                 7000
> +
> +struct ths_device;
> +
> +struct tsensor {
> +       struct ths_device               *tmdev;
> +       struct thermal_zone_device      *tzd;
> +       int                             id;
> +       wait_queue_head_t               wait_queue;
> +};
> +
> +struct ths_thermal_chip {
> +       int             sensor_num;
> +       int             offset;
> +       int             scale;
> +       int             ft_deviation;
> +       int             temp_calib_base;
> +       int             temp_data_base;
> +       int             (*calibrate)(struct ths_device *tmdev);
> +       int             (*init)(struct ths_device *tmdev);
> +       irqreturn_t     (*irq_thread)(int irq, void *data);
> +};
> +
> +struct ths_device {
> +       const struct ths_thermal_chip           *chip;
> +       struct device                           *dev;
> +       struct regmap                           *regmap;
> +       struct reset_control                    *reset;
> +       struct clk                              *bus_clk;
> +       struct tsensor                          sensor[MAX_SENSOR_NUM];
> +       int                                     data_ready;
> +};
> +
> +/* Temp Unit: millidegree Celsius */
> +static int sun8i_ths_reg2temp(struct ths_device *tmdev,
> +                             int reg)
> +{
> +       return (reg + tmdev->chip->offset) * tmdev->chip->scale;
> +}
> +
> +static int sun8i_ths_get_temp(void *data, int *temp)
> +{
> +       struct tsensor *s = data;
> +       struct ths_device *tmdev = s->tmdev;
> +       int val;
> +
> +       wait_event(s->wait_queue, tmdev->data_ready & BIT(s->id));
> +       tmdev->data_ready &= ~BIT(s->id);
> +
> +       regmap_read(tmdev->regmap, tmdev->chip->temp_data_base +
> +                   0x4 * s->id, &val);
> +
> +       *temp = sun8i_ths_reg2temp(tmdev, val);
> +       /*
> +        * XX - According to the original sdk, there are some platforms(rarely)
> +        * that add a fixed offset value after calculating the temperature
> +        * value. We can't simply put it on the formula for calculating the
> +        * temperature above, because the formula for calculating the
> +        * temperature above is also used when the sensor is calibrated. If
> +        * do this, the correct calibration formula is hard to know.
> +        */
> +       if (tmdev->chip->ft_deviation)
> +               *temp += tmdev->chip->ft_deviation;
> +
> +       return 0;
> +}
> +
> +static const struct thermal_zone_of_device_ops ths_ops = {
> +       .get_temp = sun8i_ths_get_temp,
> +};
> +
> +static const struct regmap_config config = {
> +       .reg_bits = 32,
> +       .val_bits = 32,
> +       .reg_stride = 4,
> +       .fast_io = true,
> +};
> +
> +static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
> +{
> +       wait_queue_head_t *data_wait;
> +       struct ths_device *tmdev = data;
> +       int i, state;
> +
> +       regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
> +
> +       for (i = 0; i < tmdev->chip->sensor_num; i++) {
> +               data_wait = &tmdev->sensor[i].wait_queue;
> +
> +               if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
> +                       /* clear data irq pending */
> +                       regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
> +                                    SUN50I_H6_THS_DATA_IRQ_STS(i));
> +
> +                       tmdev->data_ready |= BIT(i);
> +                       wake_up(data_wait);
> +               }
> +       }
> +
> +       return IRQ_HANDLED;
> +}
> +
> +static int sun8i_ths_resource_init(struct ths_device *tmdev)
> +{
> +       struct device *dev = tmdev->dev;
> +       struct platform_device *pdev = to_platform_device(dev);
> +       struct resource *mem;
> +       void __iomem *base;
> +       int ret, irq;
> +
> +       mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> +       base = devm_ioremap_resource(dev, mem);
> +       if (IS_ERR(base))
> +               return PTR_ERR(base);
> +
> +       tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
> +       if (IS_ERR(tmdev->regmap))
> +               return PTR_ERR(tmdev->regmap);
> +
> +       tmdev->reset = devm_reset_control_get(dev, 0);
> +       if (IS_ERR(tmdev->reset))
> +               return PTR_ERR(tmdev->reset);
> +
> +       tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
> +       if (IS_ERR(tmdev->bus_clk))
> +               return PTR_ERR(tmdev->bus_clk);
> +
> +       irq = platform_get_irq(pdev, 0);
> +       if (irq < 0)
> +               return irq;
> +
> +       ret = devm_request_threaded_irq(dev, irq, NULL,
> +                                       tmdev->chip->irq_thread,
> +                                       IRQF_ONESHOT, "ths", tmdev);
> +       if (ret)
> +               return ret;
> +
> +       ret = reset_control_deassert(tmdev->reset);
> +       if (ret)
> +               return ret;
> +
> +       ret = clk_prepare_enable(tmdev->bus_clk);
> +       if (ret)
> +               goto assert_reset;
> +
> +       ret = tmdev->chip->calibrate(tmdev);
> +       if (ret)
> +               goto bus_disable;
> +
> +       return 0;
> +
> +bus_disable:
> +       clk_disable_unprepare(tmdev->bus_clk);
> +assert_reset:
> +       reset_control_assert(tmdev->reset);
> +
> +       return ret;
> +}
> +
> +static int sun50i_ths_calibrate(struct ths_device *tmdev)
> +{
> +       struct nvmem_cell *calcell;
> +       struct device *dev = tmdev->dev;
> +       u16 *caldata;
> +       size_t callen;
> +       int ft_temp;
> +       int i, ret = 0;
> +
> +       calcell = devm_nvmem_cell_get(dev, "calib");
> +       if (IS_ERR(calcell)) {
> +               if (PTR_ERR(calcell) == -EPROBE_DEFER)
> +                       return -EPROBE_DEFER;
> +               /*
> +                * Even if the external calibration data stored in sid is
> +                * not accessible, the THS hardware can still work, although
> +                * the data won't be so accurate.
> +                *
> +                * The default value of calibration register is 0x800 for
> +                * every sensor, and the calibration value is usually 0x7xx
> +                * or 0x8xx, so they won't be away from the default value
> +                * for a lot.
> +                *
> +                * So here we do not return error if the calibartion data is
> +                * not available, except the probe needs deferring.
> +                */
> +               goto out;
> +       }
> +
> +       caldata = nvmem_cell_read(calcell, &callen);
> +       if (IS_ERR(caldata)) {
> +               ret = PTR_ERR(caldata);
> +               goto out;
> +       }
> +
> +       if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) {
> +               ret = -EINVAL;
> +               goto out_free;
> +       }
> +
> +       /*
> +        * efuse layout:
> +        *
> +        *      0   11  16       32
> +        *      +-------+-------+-------+
> +        *      |temp|  |sensor0|sensor1|
> +        *      +-------+-------+-------+
> +        *
> +        * The calibration data on the H6 is the ambient temperature and
> +        * sensor values that are filled during the factory test stage.
> +        *
> +        * The unit of stored FT temperature is 0.1 degreee celusis.
> +        * Through the stored ambient temperature and the data read
> +        * by the sensor, after a certain calculation, the calibration
> +        * value to be compensated can be obtained.
> +        */
> +       ft_temp = caldata[0] & FT_TEMP_MASK;
> +
> +       for (i = 0; i < tmdev->chip->sensor_num; i++) {
> +               int reg = (int)caldata[i + 1];
> +               int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
> +               int delta, cdata, calib_offest;
> +
> +               /*
> +                * To calculate the calibration value:
> +                *
> +                * X(in Celsius) = Ts - ft_temp
> +                * delta = X * 10000 / TEMP_TO_REG
> +                * cdata = CALIBRATE_DEFAULT - delta
> +                *
> +                * cdata: calibration value
> +                */
> +               delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
> +               cdata = CALIBRATE_DEFAULT - delta;
> +               if (cdata & ~TEMP_CALIB_MASK) {
> +                       /*
> +                        * Calibration value more than 12-bit, but calibration
> +                        * register is 12-bit. In this case, ths hardware can
> +                        * still work without calibration, although the data
> +                        * won't be so accurate.
> +                        */
> +                       dev_warn(dev, "sensor%d is not calibrated.\n", i);
> +
> +                       continue;
> +               }
> +
> +               calib_offest = tmdev->chip->temp_calib_base + (i / 2) * 0x4;
> +
> +               if (i % 2) {
> +                       int val;
> +
> +                       regmap_read(tmdev->regmap, calib_offest, &val);
> +                       val = (val & TEMP_CALIB_MASK) | (cdata << 16);
> +                       regmap_write(tmdev->regmap, calib_offest, val);
> +               } else {
> +                       regmap_write(tmdev->regmap, calib_offest, cdata);
> +               }
> +       }
> +
> +out_free:
> +       kfree(caldata);
> +out:
> +       return ret;
> +}
> +
> +static int sun8i_ths_register(struct ths_device *tmdev)
> +{
> +       struct thermal_zone_device *tzd;
> +       int i;
> +
> +       for (i = 0; i < tmdev->chip->sensor_num; i++) {
> +               tmdev->sensor[i].tmdev = tmdev;
> +               tmdev->sensor[i].id = i;
> +               tmdev->sensor[i].tzd =
> +                       devm_thermal_zone_of_sensor_register(tmdev->dev,
> +                                                            i,
> +                                                            &tmdev->sensor[i],
> +                                                            &ths_ops);
> +               if (IS_ERR(tmdev->sensor[i].tzd))
> +                       return PTR_ERR(tzd);
> +       }
> +
> +       return 0;
> +}
> +
> +static int sun8i_ths_probe(struct platform_device *pdev)
> +{
> +       struct ths_device *tmdev;
> +       struct device *dev = &pdev->dev;
> +       int i, ret;
> +
> +       tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
> +       if (!tmdev)
> +               return -ENOMEM;
> +
> +       tmdev->dev = dev;
> +       tmdev->chip = of_device_get_match_data(&pdev->dev);
> +       if (!tmdev->chip)
> +               return -EINVAL;
> +
> +       /*
> +        * Initialize wait_queue in advance, to avoid calling wake_up
> +        * before ths is registered in isr.
> +        */
> +       for (i = 0; i < tmdev->chip->sensor_num; i++)
> +               init_waitqueue_head(&tmdev->sensor[i].wait_queue);
> +
> +       platform_set_drvdata(pdev, tmdev);
> +
> +       ret = sun8i_ths_resource_init(tmdev);
> +       if (ret)
> +               return ret;
> +
> +       ret = tmdev->chip->init(tmdev);
> +       if (ret)
> +               return ret;
> +
> +       ret = sun8i_ths_register(tmdev);
> +       if (ret)
> +               return ret;
> +
> +       return ret;
> +}
> +
> +static int sun8i_ths_remove(struct platform_device *pdev)
> +{
> +       struct ths_device *tmdev = platform_get_drvdata(pdev);
> +
> +       clk_disable_unprepare(tmdev->bus_clk);
> +       reset_control_assert(tmdev->reset);
> +
> +       return 0;
> +}
> +
> +static int sun50i_thermal_init(struct ths_device *tmdev)
> +{
> +       int val;
> +
> +       /*
> +        * clkin = 24MHz
> +        * T acquire = clkin / (x + 1)
> +        *           = 20us
> +        */
> +       regmap_write(tmdev->regmap, SUN50I_THS_CTRL0,
> +                    SUN50I_THS_CTRL0_T_ACQ(479));
> +       /* average over 4 samples */
> +       regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC,
> +                    SUN50I_THS_FILTER_EN |
> +                    SUN50I_THS_FILTER_TYPE(1));
> +       /* period = (x + 1) * 4096 / clkin; ~10ms */
> +       regmap_write(tmdev->regmap, SUN50I_H6_THS_PC,
> +                    SUN50I_H6_THS_PC_TEMP_PERIOD(58));
> +       /* enable sensor */
> +       val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> +       regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val);
> +       /* thermal data interrupt enable */
> +       val = GENMASK(tmdev->chip->sensor_num - 1, 0);
> +       regmap_write(tmdev->regmap, SUN50I_H6_THS_DIC, val);
> +
> +       return 0;
> +}
> +
> +static const struct ths_thermal_chip sun50i_h6_ths = {
> +       .sensor_num = 2,
> +       .offset = -2794,
> +       .scale = -67,
> +       .ft_deviation = SUN50I_H6_FT_DEVIATION,
> +       .temp_calib_base = SUN50I_H6_THS_TEMP_CALIB,
> +       .temp_data_base = SUN50I_H6_THS_TEMP_DATA,
> +       .calibrate = sun50i_ths_calibrate,
> +       .init = sun50i_thermal_init,
> +       .irq_thread = sun50i_h6_irq_thread,
> +};
> +
> +static const struct of_device_id of_ths_match[] = {
> +       { .compatible = "allwinner,sun50i-h6-ths", .data = &sun50i_h6_ths },
> +       { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, of_ths_match);
> +
> +static struct platform_driver ths_driver = {
> +       .probe = sun8i_ths_probe,
> +       .remove = sun8i_ths_remove,
> +       .driver = {
> +               .name = "sun8i-thermal",
> +               .of_match_table = of_ths_match,
> +       },
> +};
> +module_platform_driver(ths_driver);
> +
> +MODULE_DESCRIPTION("Thermal sensor driver for Allwinner SOC");
> +MODULE_LICENSE("GPL v2");
> --
> 2.17.0
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> [e-mail]
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Yangtao Li June 11, 2019, 12:31 a.m. UTC | #9

On Tue, Jun 11, 2019 at 7:29 AM Vasily Khoruzhick <[e-mail]> wrote:
>
> On Sat, May 25, 2019 at 11:17 AM Yangtao Li <[e-mail]> wrote:
> >
> > This patch adds the support for allwinner thermal sensor, within
> > allwinner SoC. It will register sensors for thermal framework
> > and use device tree to bind cooling device.
>
> Hi Yangtao,
>
> Any plans on v4 of this series?
>

I am waiting for comment from Maxime.

I’ll support both h3 and h6 in v4.

Yangtao

Vasily Khoruzhick June 11, 2019, 12:34 a.m. UTC | #10

On Mon, Jun 10, 2019 at 5:31 PM Frank Lee <[e-mail]> wrote:
>
> On Tue, Jun 11, 2019 at 7:29 AM Vasily Khoruzhick <[e-mail]> wrote:
> >
> > On Sat, May 25, 2019 at 11:17 AM Yangtao Li <[e-mail]> wrote:
> > >
> > > This patch adds the support for allwinner thermal sensor, within
> > > allwinner SoC. It will register sensors for thermal framework
> > > and use device tree to bind cooling device.
> >
> > Hi Yangtao,
> >
> > Any plans on v4 of this series?
> >
>
> I am waiting for comment from Maxime.
>
> I’ll support both h3 and h6 in v4.

If you have a git tree I'll be happy to contribute A64 support. IIRC
it was quite similar to H3.

> Yangtao

Maxime Ripard June 12, 2019, 3:43 p.m. UTC | #11

On Fri, Jun 07, 2019 at 09:34:44PM +0800, Frank Lee wrote:
> On Mon, May 27, 2019 at 8:27 PM Maxime Ripard <[e-mail]> wrote:
> > > +     ret = devm_request_threaded_irq(dev, irq, NULL,
> > > +                                     tmdev->chip->irq_thread,
> > > +                                     IRQF_ONESHOT, "ths", tmdev);
> > > +     if (ret)
> > > +             return ret;
> >
> > Is there any particular reason to use a threaded interrupt?
>
> Just to improve real-time.

What do you mean by real-time here? If anything, that will increase
the latency of the interrupts here.

And in preempt-rt, regular top-half interrupts will be forced into a
threaded interrupt anyway.

> > > +static int sun8i_ths_remove(struct platform_device *pdev)
> > > +{
> > > +     struct ths_device *tmdev = platform_get_drvdata(pdev);
> > > +
> > > +     clk_disable_unprepare(tmdev->bus_clk);
> >
> > I know that we discussed that already, but I'm not sure why you switch
> > back to a regular call to regmap_init_mmio, while regmap_init_mmio_clk
> > will take care of enabling and disabling the bus clock for you?
>
> It seems that regmap_init_mmio_clk just get clk and prepare clk
> but no enable.

At init time, yes. But it will enable it only when you access the
registers, which is what you want anyway.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Yangtao Li June 12, 2019, 4:49 p.m. UTC | #12

> If you have a git tree I'll be happy to contribute A64 support. IIRC
> it was quite similar to H3.

I built a ths branch and I will do some work later.

https://github.com/TinyWindzz/linux/tree/ths

Yangtao Li June 13, 2019, 3:35 p.m. UTC | #13

On Thu, Jun 13, 2019 at 9:26 PM Maxime Ripard <[e-mail]> wrote:
>
> On Fri, Jun 07, 2019 at 09:34:44PM +0800, Frank Lee wrote:
> > On Mon, May 27, 2019 at 8:27 PM Maxime Ripard <[e-mail]> wrote:
> > > > +     ret = devm_request_threaded_irq(dev, irq, NULL,
> > > > +                                     tmdev->chip->irq_thread,
> > > > +                                     IRQF_ONESHOT, "ths", tmdev);
> > > > +     if (ret)
> > > > +             return ret;
> > >
> > > Is there any particular reason to use a threaded interrupt?
> >
> > Just to improve real-time.
>
> What do you mean by real-time here? If anything, that will increase
> the latency of the interrupts here.
>
> And in preempt-rt, regular top-half interrupts will be forced into a
> threaded interrupt anyway.
>
> > > > +static int sun8i_ths_remove(struct platform_device *pdev)
> > > > +{
> > > > +     struct ths_device *tmdev = platform_get_drvdata(pdev);
> > > > +
> > > > +     clk_disable_unprepare(tmdev->bus_clk);
> > >
> > > I know that we discussed that already, but I'm not sure why you switch
> > > back to a regular call to regmap_init_mmio, while regmap_init_mmio_clk
> > > will take care of enabling and disabling the bus clock for you?
> >
> > It seems that regmap_init_mmio_clk just get clk and prepare clk
> > but no enable.
>
> At init time, yes. But it will enable it only when you access the
> registers, which is what you want anyway.

But after accessing the register, it turns the clock off, which
affects the ad conversion and the occurrence of the interrupt.

In addition, when resuming from suspend, we need to enable
the clock, so I think it is necessary to have a clock pointer.

Yangtao

>
> Maxime
>
> --
> Maxime Ripard, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com

Maxime Ripard June 14, 2019, 8:02 a.m. UTC | #14

Hi,

On Thu, Jun 13, 2019 at 11:35:15PM +0800, Frank Lee wrote:
> On Thu, Jun 13, 2019 at 9:26 PM Maxime Ripard <[e-mail]> wrote:
> >
> > On Fri, Jun 07, 2019 at 09:34:44PM +0800, Frank Lee wrote:
> > > On Mon, May 27, 2019 at 8:27 PM Maxime Ripard <[e-mail]> wrote:
> > > > > +     ret = devm_request_threaded_irq(dev, irq, NULL,
> > > > > +                                     tmdev->chip->irq_thread,
> > > > > +                                     IRQF_ONESHOT, "ths", tmdev);
> > > > > +     if (ret)
> > > > > +             return ret;
> > > >
> > > > Is there any particular reason to use a threaded interrupt?
> > >
> > > Just to improve real-time.
> >
> > What do you mean by real-time here? If anything, that will increase
> > the latency of the interrupts here.
> >
> > And in preempt-rt, regular top-half interrupts will be forced into a
> > threaded interrupt anyway.
> >
> > > > > +static int sun8i_ths_remove(struct platform_device *pdev)
> > > > > +{
> > > > > +     struct ths_device *tmdev = platform_get_drvdata(pdev);
> > > > > +
> > > > > +     clk_disable_unprepare(tmdev->bus_clk);
> > > >
> > > > I know that we discussed that already, but I'm not sure why you switch
> > > > back to a regular call to regmap_init_mmio, while regmap_init_mmio_clk
> > > > will take care of enabling and disabling the bus clock for you?
> > >
> > > It seems that regmap_init_mmio_clk just get clk and prepare clk
> > > but no enable.
> >
> > At init time, yes. But it will enable it only when you access the
> > registers, which is what you want anyway.
>
> But after accessing the register, it turns the clock off, which
> affects the ad conversion and the occurrence of the interrupt.

Ah, so that's how it works. Yeah, it makes sense then.

> In addition, when resuming from suspend, we need to enable
> the clock, so I think it is necessary to have a clock pointer.

Yep, indeed.

Maxime

--
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Vasily Khoruzhick June 14, 2019, 11:07 p.m. UTC | #15

On Wed, Jun 12, 2019 at 9:50 AM Frank Lee <[e-mail]> wrote:
>
> > If you have a git tree I'll be happy to contribute A64 support. IIRC
> > it was quite similar to H3.
>
> I built a ths branch and I will do some work later.
>
> https://github.com/TinyWindzz/linux/tree/ths

Looks like you forgot to add your patches to this branch.

Yangtao Li June 16, 2019, 3:27 p.m. UTC | #16

On Sat, Jun 15, 2019 at 7:08 AM Vasily Khoruzhick <[e-mail]> wrote:
>
> On Wed, Jun 12, 2019 at 9:50 AM Frank Lee <[e-mail]> wrote:
> >
> > > If you have a git tree I'll be happy to contribute A64 support. IIRC
> > > it was quite similar to H3.
> >
> > I built a ths branch and I will do some work later.
> >
> > https://github.com/TinyWindzz/linux/tree/ths
>
> Looks like you forgot to add your patches to this branch.

Frankly, I started the new version this weekend. There is still a
small part of the
hand that has not been completed, and I will push patches to my branch
these two days.

MBR,
Yangtao

Yangtao Li June 18, 2019, 7:04 p.m. UTC | #17

On Sat, Jun 15, 2019 at 7:08 AM Vasily Khoruzhick <[e-mail]> wrote:
>
> On Wed, Jun 12, 2019 at 9:50 AM Frank Lee <[e-mail]> wrote:
> >
> > > If you have a git tree I'll be happy to contribute A64 support. IIRC
> > > it was quite similar to H3.
> >
> > I built a ths branch and I will do some work later.
> >
> > https://github.com/TinyWindzz/linux/tree/ths
>
> Looks like you forgot to add your patches to this branch.

Done.

Patch

diff --git a/MAINTAINERS b/MAINTAINERS
index 2336dd26ece4..d312f9eecf0d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -674,6 +674,13 @@  L:	[e-mail]
 S:	Maintained
 F:	drivers/crypto/sunxi-ss/
 
+ALLWINNER THERMAL DRIVER
+M:	Yangtao Li <[e-mail]>
+L:	[e-mail]
+S:	Maintained
+F:	Documentation/devicetree/bindings/thermal/sun8i-thermal.yaml
+F:	drivers/thermal/sun8i_thermal.c
+
 ALLWINNER VPU DRIVER
 M:	Maxime Ripard <[e-mail]>
 M:	Paul Kocialkowski <[e-mail]>
diff --git a/drivers/thermal/Kconfig b/drivers/thermal/Kconfig
index 9966364a6deb..e5465053d66f 100644
--- a/drivers/thermal/Kconfig
+++ b/drivers/thermal/Kconfig
@@ -262,6 +262,20 @@  config SPEAR_THERMAL
 	  Enable this to plug the SPEAr thermal sensor driver into the Linux
 	  thermal framework.
 
+config SUN8I_THERMAL
+	tristate "Allwinner sun8i thermal driver"
+	depends on ARCH_SUNXI || COMPILE_TEST
+	depends on HAS_IOMEM
+	depends on NVMEM_SUNXI_SID
+	depends on OF
+	depends on RESET_CONTROLLER
+	help
+	  Support for the sun8i thermal sensor driver into the Linux thermal
+	  framework.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called sun8i-thermal.
+
 config ROCKCHIP_THERMAL
 	tristate "Rockchip thermal driver"
 	depends on ARCH_ROCKCHIP || COMPILE_TEST
diff --git a/drivers/thermal/Makefile b/drivers/thermal/Makefile
index 74a37c7f847a..fa6f8b206281 100644
--- a/drivers/thermal/Makefile
+++ b/drivers/thermal/Makefile
@@ -31,6 +31,7 @@  thermal_sys-$(CONFIG_DEVFREQ_THERMAL) += devfreq_cooling.o
 obj-y				+= broadcom/
 obj-$(CONFIG_THERMAL_MMIO)		+= thermal_mmio.o
 obj-$(CONFIG_SPEAR_THERMAL)	+= spear_thermal.o
+obj-$(CONFIG_SUN8I_THERMAL)     += sun8i_thermal.o
 obj-$(CONFIG_ROCKCHIP_THERMAL)	+= rockchip_thermal.o
 obj-$(CONFIG_RCAR_THERMAL)	+= rcar_thermal.o
 obj-$(CONFIG_RCAR_GEN3_THERMAL)	+= rcar_gen3_thermal.o
diff --git a/drivers/thermal/sun8i_thermal.c b/drivers/thermal/sun8i_thermal.c
new file mode 100644
index 000000000000..a9cc2197f4cb
--- /dev/null
+++ b/drivers/thermal/sun8i_thermal.c
@@ -0,0 +1,437 @@ 
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Thermal sensor driver for Allwinner SOC
+ * Copyright (C) 2019 Yangtao Li
+ *
+ * Based on the work of Icenowy Zheng <[e-mail]>
+ * Based on the work of Ondrej Jirman <[e-mail]>
+ * Based on the work of Josef Gajdusek <[e-mail]>
+ */
+
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/interrupt.h>
+#include <linux/wait.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/thermal.h>
+
+#define MAX_SENSOR_NUM	4
+
+#define FT_TEMP_MASK				GENMASK(11, 0)
+#define TEMP_CALIB_MASK				GENMASK(11, 0)
+#define TEMP_TO_REG				672
+#define CALIBRATE_DEFAULT			0x800
+
+#define SUN50I_THS_CTRL0			0x00
+#define SUN50I_H6_THS_ENABLE			0x04
+#define SUN50I_H6_THS_PC			0x08
+#define SUN50I_H6_THS_DIC			0x10
+#define SUN50I_H6_THS_DIS			0x20
+#define SUN50I_H6_THS_MFC			0x30
+#define SUN50I_H6_THS_TEMP_CALIB		0xa0
+#define SUN50I_H6_THS_TEMP_DATA			0xc0
+
+#define SUN50I_THS_CTRL0_T_ACQ(x)		((GENMASK(15, 0) & (x)) << 16)
+#define SUN50I_THS_FILTER_EN			BIT(2)
+#define SUN50I_THS_FILTER_TYPE(x)		(GENMASK(1, 0) & (x))
+#define SUN50I_H6_THS_PC_TEMP_PERIOD(x)		((GENMASK(19, 0) & (x)) << 12)
+#define SUN50I_H6_THS_DATA_IRQ_STS(x)		BIT(x)
+
+/* millidegree celsius */
+#define SUN50I_H6_FT_DEVIATION			7000
+
+struct ths_device;
+
+struct tsensor {
+	struct ths_device		*tmdev;
+	struct thermal_zone_device	*tzd;
+	int				id;
+	wait_queue_head_t		wait_queue;
+};
+
+struct ths_thermal_chip {
+	int		sensor_num;
+	int		offset;
+	int		scale;
+	int		ft_deviation;
+	int		temp_calib_base;
+	int		temp_data_base;
+	int		(*calibrate)(struct ths_device *tmdev);
+	int		(*init)(struct ths_device *tmdev);
+	irqreturn_t	(*irq_thread)(int irq, void *data);
+};
+
+struct ths_device {
+	const struct ths_thermal_chip		*chip;
+	struct device				*dev;
+	struct regmap				*regmap;
+	struct reset_control			*reset;
+	struct clk				*bus_clk;
+	struct tsensor				sensor[MAX_SENSOR_NUM];
+	int					data_ready;
+};
+
+/* Temp Unit: millidegree Celsius */
+static int sun8i_ths_reg2temp(struct ths_device *tmdev,
+			      int reg)
+{
+	return (reg + tmdev->chip->offset) * tmdev->chip->scale;
+}
+
+static int sun8i_ths_get_temp(void *data, int *temp)
+{
+	struct tsensor *s = data;
+	struct ths_device *tmdev = s->tmdev;
+	int val;
+
+	wait_event(s->wait_queue, tmdev->data_ready & BIT(s->id));
+	tmdev->data_ready &= ~BIT(s->id);
+
+	regmap_read(tmdev->regmap, tmdev->chip->temp_data_base +
+		    0x4 * s->id, &val);
+
+	*temp = sun8i_ths_reg2temp(tmdev, val);
+	/*
+	 * XX - According to the original sdk, there are some platforms(rarely)
+	 * that add a fixed offset value after calculating the temperature
+	 * value. We can't simply put it on the formula for calculating the
+	 * temperature above, because the formula for calculating the
+	 * temperature above is also used when the sensor is calibrated. If
+	 * do this, the correct calibration formula is hard to know.
+	 */
+	if (tmdev->chip->ft_deviation)
+		*temp += tmdev->chip->ft_deviation;
+
+	return 0;
+}
+
+static const struct thermal_zone_of_device_ops ths_ops = {
+	.get_temp = sun8i_ths_get_temp,
+};
+
+static const struct regmap_config config = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.fast_io = true,
+};
+
+static irqreturn_t sun50i_h6_irq_thread(int irq, void *data)
+{
+	wait_queue_head_t *data_wait;
+	struct ths_device *tmdev = data;
+	int i, state;
+
+	regmap_read(tmdev->regmap, SUN50I_H6_THS_DIS, &state);
+
+	for (i = 0; i < tmdev->chip->sensor_num; i++) {
+		data_wait = &tmdev->sensor[i].wait_queue;
+
+		if (state & SUN50I_H6_THS_DATA_IRQ_STS(i)) {
+			/* clear data irq pending */
+			regmap_write(tmdev->regmap, SUN50I_H6_THS_DIS,
+				     SUN50I_H6_THS_DATA_IRQ_STS(i));
+
+			tmdev->data_ready |= BIT(i);
+			wake_up(data_wait);
+		}
+	}
+
+	return IRQ_HANDLED;
+}
+
+static int sun8i_ths_resource_init(struct ths_device *tmdev)
+{
+	struct device *dev = tmdev->dev;
+	struct platform_device *pdev = to_platform_device(dev);
+	struct resource *mem;
+	void __iomem *base;
+	int ret, irq;
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	base = devm_ioremap_resource(dev, mem);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	tmdev->regmap = devm_regmap_init_mmio(dev, base, &config);
+	if (IS_ERR(tmdev->regmap))
+		return PTR_ERR(tmdev->regmap);
+
+	tmdev->reset = devm_reset_control_get(dev, 0);
+	if (IS_ERR(tmdev->reset))
+		return PTR_ERR(tmdev->reset);
+
+	tmdev->bus_clk = devm_clk_get(&pdev->dev, "bus");
+	if (IS_ERR(tmdev->bus_clk))
+		return PTR_ERR(tmdev->bus_clk);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	ret = devm_request_threaded_irq(dev, irq, NULL,
+					tmdev->chip->irq_thread,
+					IRQF_ONESHOT, "ths", tmdev);
+	if (ret)
+		return ret;
+
+	ret = reset_control_deassert(tmdev->reset);
+	if (ret)
+		return ret;
+
+	ret = clk_prepare_enable(tmdev->bus_clk);
+	if (ret)
+		goto assert_reset;
+
+	ret = tmdev->chip->calibrate(tmdev);
+	if (ret)
+		goto bus_disable;
+
+	return 0;
+
+bus_disable:
+	clk_disable_unprepare(tmdev->bus_clk);
+assert_reset:
+	reset_control_assert(tmdev->reset);
+
+	return ret;
+}
+
+static int sun50i_ths_calibrate(struct ths_device *tmdev)
+{
+	struct nvmem_cell *calcell;
+	struct device *dev = tmdev->dev;
+	u16 *caldata;
+	size_t callen;
+	int ft_temp;
+	int i, ret = 0;
+
+	calcell = devm_nvmem_cell_get(dev, "calib");
+	if (IS_ERR(calcell)) {
+		if (PTR_ERR(calcell) == -EPROBE_DEFER)
+			return -EPROBE_DEFER;
+		/*
+		 * Even if the external calibration data stored in sid is
+		 * not accessible, the THS hardware can still work, although
+		 * the data won't be so accurate.
+		 *
+		 * The default value of calibration register is 0x800 for
+		 * every sensor, and the calibration value is usually 0x7xx
+		 * or 0x8xx, so they won't be away from the default value
+		 * for a lot.
+		 *
+		 * So here we do not return error if the calibartion data is
+		 * not available, except the probe needs deferring.
+		 */
+		goto out;
+	}
+
+	caldata = nvmem_cell_read(calcell, &callen);
+	if (IS_ERR(caldata)) {
+		ret = PTR_ERR(caldata);
+		goto out;
+	}
+
+	if (!caldata[0] || callen < 2 + 2 * tmdev->chip->sensor_num) {
+		ret = -EINVAL;
+		goto out_free;
+	}
+
+	/*
+	 * efuse layout:
+	 *
+	 *	0   11  16	 32
+	 *	+-------+-------+-------+
+	 *	|temp|  |sensor0|sensor1|
+	 *	+-------+-------+-------+
+	 *
+	 * The calibration data on the H6 is the ambient temperature and
+	 * sensor values that are filled during the factory test stage.
+	 *
+	 * The unit of stored FT temperature is 0.1 degreee celusis.
+	 * Through the stored ambient temperature and the data read
+	 * by the sensor, after a certain calculation, the calibration
+	 * value to be compensated can be obtained.
+	 */
+	ft_temp = caldata[0] & FT_TEMP_MASK;
+
+	for (i = 0; i < tmdev->chip->sensor_num; i++) {
+		int reg = (int)caldata[i + 1];
+		int sensor_temp = sun8i_ths_reg2temp(tmdev, reg);
+		int delta, cdata, calib_offest;
+
+		/*
+		 * To calculate the calibration value:
+		 *
+		 * X(in Celsius) = Ts - ft_temp
+		 * delta = X * 10000 / TEMP_TO_REG
+		 * cdata = CALIBRATE_DEFAULT - delta
+		 *
+		 * cdata: calibration value
+		 */
+		delta = (sensor_temp - ft_temp * 100) * 10 / TEMP_TO_REG;
+		cdata = CALIBRATE_DEFAULT - delta;
+		if (cdata & ~TEMP_CALIB_MASK) {
+			/*
+			 * Calibration value more than 12-bit, but calibration
+			 * register is 12-bit. In this case, ths hardware can
+			 * still work without calibration, although the data
+			 * won't be so accurate.
+			 */
+			dev_warn(dev, "sensor%d is not calibrated.\n", i);
+
+			continue;
+		}
+
+		calib_offest = tmdev->chip->temp_calib_base + (i / 2) * 0x4;
+
+		if (i % 2) {
+			int val;
+
+			regmap_read(tmdev->regmap, calib_offest, &val);
+			val = (val & TEMP_CALIB_MASK) | (cdata << 16);
+			regmap_write(tmdev->regmap, calib_offest, val);
+		} else {
+			regmap_write(tmdev->regmap, calib_offest, cdata);
+		}
+	}
+
+out_free:
+	kfree(caldata);
+out:
+	return ret;
+}
+
+static int sun8i_ths_register(struct ths_device *tmdev)
+{
+	struct thermal_zone_device *tzd;
+	int i;
+
+	for (i = 0; i < tmdev->chip->sensor_num; i++) {
+		tmdev->sensor[i].tmdev = tmdev;
+		tmdev->sensor[i].id = i;
+		tmdev->sensor[i].tzd =
+			devm_thermal_zone_of_sensor_register(tmdev->dev,
+							     i,
+							     &tmdev->sensor[i],
+							     &ths_ops);
+		if (IS_ERR(tmdev->sensor[i].tzd))
+			return PTR_ERR(tzd);
+	}
+
+	return 0;
+}
+
+static int sun8i_ths_probe(struct platform_device *pdev)
+{
+	struct ths_device *tmdev;
+	struct device *dev = &pdev->dev;
+	int i, ret;
+
+	tmdev = devm_kzalloc(dev, sizeof(*tmdev), GFP_KERNEL);
+	if (!tmdev)
+		return -ENOMEM;
+
+	tmdev->dev = dev;
+	tmdev->chip = of_device_get_match_data(&pdev->dev);
+	if (!tmdev->chip)
+		return -EINVAL;
+
+	/*
+	 * Initialize wait_queue in advance, to avoid calling wake_up
+	 * before ths is registered in isr.
+	 */
+	for (i = 0; i < tmdev->chip->sensor_num; i++)
+		init_waitqueue_head(&tmdev->sensor[i].wait_queue);
+
+	platform_set_drvdata(pdev, tmdev);
+
+	ret = sun8i_ths_resource_init(tmdev);
+	if (ret)
+		return ret;
+
+	ret = tmdev->chip->init(tmdev);
+	if (ret)
+		return ret;
+
+	ret = sun8i_ths_register(tmdev);
+	if (ret)
+		return ret;
+
+	return ret;
+}
+
+static int sun8i_ths_remove(struct platform_device *pdev)
+{
+	struct ths_device *tmdev = platform_get_drvdata(pdev);
+
+	clk_disable_unprepare(tmdev->bus_clk);
+	reset_control_assert(tmdev->reset);
+
+	return 0;
+}
+
+static int sun50i_thermal_init(struct ths_device *tmdev)
+{
+	int val;
+
+	/*
+	 * clkin = 24MHz
+	 * T acquire = clkin / (x + 1)
+	 *           = 20us
+	 */
+	regmap_write(tmdev->regmap, SUN50I_THS_CTRL0,
+		     SUN50I_THS_CTRL0_T_ACQ(479));
+	/* average over 4 samples */
+	regmap_write(tmdev->regmap, SUN50I_H6_THS_MFC,
+		     SUN50I_THS_FILTER_EN |
+		     SUN50I_THS_FILTER_TYPE(1));
+	/* period = (x + 1) * 4096 / clkin; ~10ms */
+	regmap_write(tmdev->regmap, SUN50I_H6_THS_PC,
+		     SUN50I_H6_THS_PC_TEMP_PERIOD(58));
+	/* enable sensor */
+	val = GENMASK(tmdev->chip->sensor_num - 1, 0);
+	regmap_write(tmdev->regmap, SUN50I_H6_THS_ENABLE, val);
+	/* thermal data interrupt enable */
+	val = GENMASK(tmdev->chip->sensor_num - 1, 0);
+	regmap_write(tmdev->regmap, SUN50I_H6_THS_DIC, val);
+
+	return 0;
+}
+
+static const struct ths_thermal_chip sun50i_h6_ths = {
+	.sensor_num = 2,
+	.offset = -2794,
+	.scale = -67,
+	.ft_deviation = SUN50I_H6_FT_DEVIATION,
+	.temp_calib_base = SUN50I_H6_THS_TEMP_CALIB,
+	.temp_data_base = SUN50I_H6_THS_TEMP_DATA,
+	.calibrate = sun50i_ths_calibrate,
+	.init = sun50i_thermal_init,
+	.irq_thread = sun50i_h6_irq_thread,
+};
+
+static const struct of_device_id of_ths_match[] = {
+	{ .compatible = "allwinner,sun50i-h6-ths", .data = &sun50i_h6_ths },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, of_ths_match);
+
+static struct platform_driver ths_driver = {
+	.probe = sun8i_ths_probe,
+	.remove = sun8i_ths_remove,
+	.driver = {
+		.name = "sun8i-thermal",
+		.of_match_table = of_ths_match,
+	},
+};
+module_platform_driver(ths_driver);
+
+MODULE_DESCRIPTION("Thermal sensor driver for Allwinner SOC");
+MODULE_LICENSE("GPL v2");