| Message ID | 99519eef99d2324019f0b44a4296c518eac47f95.1433263218.git.cyrille.pitchen@atmel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Le 02/06/2015 18:49, Cyrille Pitchen a écrit : > Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com> > > This driver supports the new Atmel Flexcom. The Flexcom is a wrapper which > integrates one SPI controller, one I2C controller and one USART. Only one > function can be enabled at a time. This driver selects the function once for > all, when the Flexcom is probed, according to the value of the new > "atmel,flexcom-mode" device tree property. > > This driver has chosen to present the Flexcom to the system as a clock so the > implementation is seamless for the existing Atmel SPI, I2C and USART drivers. > > Also the Flexcom embeds FIFOs: the latest patches of the SPI, I2C and USART > drivers take advantage of this new feature. > > Conflicts: > drivers/clk/at91/Makefile issue with the commit message: sending a new series Cyrille > --- > arch/arm/mach-at91/Kconfig | 3 + > drivers/clk/at91/Makefile | 1 + > drivers/clk/at91/clk-flexcom.c | 160 +++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 164 insertions(+) > create mode 100644 drivers/clk/at91/clk-flexcom.c > > diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig > index fd95f34..8ce9b73 100644 > --- a/arch/arm/mach-at91/Kconfig > +++ b/arch/arm/mach-at91/Kconfig > @@ -90,6 +90,9 @@ config HAVE_AT91_SMD > config HAVE_AT91_H32MX > bool > > +config HAVE_AT91_FLEXCOM > + bool > + > config SOC_SAM_V4_V5 > bool > > diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile > index 89a48a7..74711b8 100644 > --- a/drivers/clk/at91/Makefile > +++ b/drivers/clk/at91/Makefile > @@ -10,3 +10,4 @@ obj-$(CONFIG_HAVE_AT91_UTMI) += clk-utmi.o > obj-$(CONFIG_HAVE_AT91_USB_CLK) += clk-usb.o > obj-$(CONFIG_HAVE_AT91_SMD) += clk-smd.o > obj-$(CONFIG_HAVE_AT91_H32MX) += clk-h32mx.o > +obj-$(CONFIG_HAVE_AT91_FLEXCOM) += clk-flexcom.o > diff --git a/drivers/clk/at91/clk-flexcom.c b/drivers/clk/at91/clk-flexcom.c > new file mode 100644 > index 0000000..ce39093 > --- /dev/null > +++ b/drivers/clk/at91/clk-flexcom.c > @@ -0,0 +1,160 @@ > +/* > + * Driver for Atmel AT91 Flexcom > + * > + * Copyright (C) 2014 Atmel Corporation > + * > + * Author: Cyrille Pitchen <cyrille.pitchen@atmel.com> > + * > + * Based on drivers/clk/clk-axi-clkgen.c > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + * > + */ > + > +#include <linux/platform_device.h> > +#include <linux/clk-provider.h> > +#include <linux/of.h> > +#include <linux/module.h> > + > + > +#define FX_MR 0x0 > +#define FX_RHR 0x10 > +#define FX_THR 0x20 > +#define FX_VERSION 0xfc > + > +#define FX_MR_NO_COM 0 > +#define FX_MR_USART 1 > +#define FX_MR_SPI 2 > +#define FX_MR_TWI 3 > + > +struct clk_flexcom { > + struct clk_hw hw; > + struct device *dev; > + u8 __iomem *base; > + u32 mr; > + bool show_once; > +}; > + > +#define to_clk_flexcom(_hw) container_of(_hw, struct clk_flexcom, hw) > + > + > +static int at91_flexcom_enable(struct clk_hw *hw) > +{ > + struct clk_flexcom *dev = to_clk_flexcom(hw); > + u32 version; > + > + if (!dev->show_once) { > + dev->show_once = true; > + version = __raw_readl(dev->base + FX_VERSION); > + dev_info(dev->dev, "version: %#x\n", version); > + } > + > + __raw_writel(dev->mr, dev->base + FX_MR); > + return 0; > +} > + > +static void at91_flexcom_disable(struct clk_hw *hw) > +{ > + struct clk_flexcom *dev = to_clk_flexcom(hw); > + > + __raw_writel(FX_MR_NO_COM, dev->base + FX_MR); > +} > + > +static const struct clk_ops at91_flexcom_ops = { > + .enable = at91_flexcom_enable, > + .disable = at91_flexcom_disable, > +}; > + > +static int at91_flexcom_probe(struct platform_device *pdev) > +{ > + struct device_node *np = pdev->dev.of_node; > + struct clk_flexcom *dev; > + struct resource *mem; > + const char *parent_name, *clk_name, *mode; > + struct clk *clk; > + struct clk_init_data init; > + u32 mr = FX_MR_NO_COM; > + int err; > + > + if (!np) > + return -ENODEV; > + > + err = of_property_read_string(np, "atmel,flexcom-mode", &mode); > + if (err) > + return err; > + > + if (!strcmp(mode, "usart")) > + mr = FX_MR_USART; > + else if (!strcmp(mode, "spi")) > + mr = FX_MR_SPI; > + else if (!strcmp(mode, "twi") || !strcmp(mode, "i2c")) > + mr = FX_MR_TWI; > + else > + return -EINVAL; > + > + dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); > + if (!dev) > + return -ENOMEM; > + > + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + dev->base = devm_ioremap_resource(&pdev->dev, mem); > + if (IS_ERR(dev->base)) > + return PTR_ERR(dev->base); > + > + parent_name = of_clk_get_parent_name(np, 0); > + if (!parent_name) > + return -EINVAL; > + > + clk_name = np->name; > + of_property_read_string(np, "clock-output-names", &clk_name); > + > + init.name = clk_name; > + init.ops = &at91_flexcom_ops; > + init.flags = 0; > + init.parent_names = &parent_name; > + init.num_parents = 1; > + > + dev->hw.init = &init; > + dev->dev = &pdev->dev; > + dev->mr = mr; > + platform_set_drvdata(pdev, dev); > + > + clk = devm_clk_register(&pdev->dev, &dev->hw); > + if (IS_ERR(clk)) > + return PTR_ERR(clk); > + > + return of_clk_add_provider(np, of_clk_src_simple_get, clk); > +} > + > +static int at91_flexcom_remove(struct platform_device *pdev) > +{ > + of_clk_del_provider(pdev->dev.of_node); > + > + return 0; > +} > + > +static const struct of_device_id at91_flexcom_dt_ids[] = { > + { .compatible = "atmel,sama5d2-flexcom" }, > + { /* sentinel */ } > +}; > + > +MODULE_DEVICE_TABLE(of, at91_flexcom_dt_ids); > + > +static struct platform_driver at91_flexcom_driver = { > + .driver = { > + .name = "at91_flexcom", > + .of_match_table = of_match_ptr(at91_flexcom_dt_ids), > + }, > + .probe = at91_flexcom_probe, > + .remove = at91_flexcom_remove, > +}; > +module_platform_driver(at91_flexcom_driver); > + > +MODULE_ALIAS("platform:at91_flexcom"); > +MODULE_DESCRIPTION("Atmel AT91 Flexcom driver"); > +MODULE_AUTHOR("Cyrille Pitchen <cyrille.pitchen@atmel.com>"); > +MODULE_LICENSE("GPL v2"); > + >
diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig index fd95f34..8ce9b73 100644 --- a/arch/arm/mach-at91/Kconfig +++ b/arch/arm/mach-at91/Kconfig @@ -90,6 +90,9 @@ config HAVE_AT91_SMD config HAVE_AT91_H32MX bool +config HAVE_AT91_FLEXCOM + bool + config SOC_SAM_V4_V5 bool diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile index 89a48a7..74711b8 100644 --- a/drivers/clk/at91/Makefile +++ b/drivers/clk/at91/Makefile @@ -10,3 +10,4 @@ obj-$(CONFIG_HAVE_AT91_UTMI) += clk-utmi.o obj-$(CONFIG_HAVE_AT91_USB_CLK) += clk-usb.o obj-$(CONFIG_HAVE_AT91_SMD) += clk-smd.o obj-$(CONFIG_HAVE_AT91_H32MX) += clk-h32mx.o +obj-$(CONFIG_HAVE_AT91_FLEXCOM) += clk-flexcom.o diff --git a/drivers/clk/at91/clk-flexcom.c b/drivers/clk/at91/clk-flexcom.c new file mode 100644 index 0000000..ce39093 --- /dev/null +++ b/drivers/clk/at91/clk-flexcom.c @@ -0,0 +1,160 @@ +/* + * Driver for Atmel AT91 Flexcom + * + * Copyright (C) 2014 Atmel Corporation + * + * Author: Cyrille Pitchen <cyrille.pitchen@atmel.com> + * + * Based on drivers/clk/clk-axi-clkgen.c + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + */ + +#include <linux/platform_device.h> +#include <linux/clk-provider.h> +#include <linux/of.h> +#include <linux/module.h> + + +#define FX_MR 0x0 +#define FX_RHR 0x10 +#define FX_THR 0x20 +#define FX_VERSION 0xfc + +#define FX_MR_NO_COM 0 +#define FX_MR_USART 1 +#define FX_MR_SPI 2 +#define FX_MR_TWI 3 + +struct clk_flexcom { + struct clk_hw hw; + struct device *dev; + u8 __iomem *base; + u32 mr; + bool show_once; +}; + +#define to_clk_flexcom(_hw) container_of(_hw, struct clk_flexcom, hw) + + +static int at91_flexcom_enable(struct clk_hw *hw) +{ + struct clk_flexcom *dev = to_clk_flexcom(hw); + u32 version; + + if (!dev->show_once) { + dev->show_once = true; + version = __raw_readl(dev->base + FX_VERSION); + dev_info(dev->dev, "version: %#x\n", version); + } + + __raw_writel(dev->mr, dev->base + FX_MR); + return 0; +} + +static void at91_flexcom_disable(struct clk_hw *hw) +{ + struct clk_flexcom *dev = to_clk_flexcom(hw); + + __raw_writel(FX_MR_NO_COM, dev->base + FX_MR); +} + +static const struct clk_ops at91_flexcom_ops = { + .enable = at91_flexcom_enable, + .disable = at91_flexcom_disable, +}; + +static int at91_flexcom_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct clk_flexcom *dev; + struct resource *mem; + const char *parent_name, *clk_name, *mode; + struct clk *clk; + struct clk_init_data init; + u32 mr = FX_MR_NO_COM; + int err; + + if (!np) + return -ENODEV; + + err = of_property_read_string(np, "atmel,flexcom-mode", &mode); + if (err) + return err; + + if (!strcmp(mode, "usart")) + mr = FX_MR_USART; + else if (!strcmp(mode, "spi")) + mr = FX_MR_SPI; + else if (!strcmp(mode, "twi") || !strcmp(mode, "i2c")) + mr = FX_MR_TWI; + else + return -EINVAL; + + dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + + mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + dev->base = devm_ioremap_resource(&pdev->dev, mem); + if (IS_ERR(dev->base)) + return PTR_ERR(dev->base); + + parent_name = of_clk_get_parent_name(np, 0); + if (!parent_name) + return -EINVAL; + + clk_name = np->name; + of_property_read_string(np, "clock-output-names", &clk_name); + + init.name = clk_name; + init.ops = &at91_flexcom_ops; + init.flags = 0; + init.parent_names = &parent_name; + init.num_parents = 1; + + dev->hw.init = &init; + dev->dev = &pdev->dev; + dev->mr = mr; + platform_set_drvdata(pdev, dev); + + clk = devm_clk_register(&pdev->dev, &dev->hw); + if (IS_ERR(clk)) + return PTR_ERR(clk); + + return of_clk_add_provider(np, of_clk_src_simple_get, clk); +} + +static int at91_flexcom_remove(struct platform_device *pdev) +{ + of_clk_del_provider(pdev->dev.of_node); + + return 0; +} + +static const struct of_device_id at91_flexcom_dt_ids[] = { + { .compatible = "atmel,sama5d2-flexcom" }, + { /* sentinel */ } +}; + +MODULE_DEVICE_TABLE(of, at91_flexcom_dt_ids); + +static struct platform_driver at91_flexcom_driver = { + .driver = { + .name = "at91_flexcom", + .of_match_table = of_match_ptr(at91_flexcom_dt_ids), + }, + .probe = at91_flexcom_probe, + .remove = at91_flexcom_remove, +}; +module_platform_driver(at91_flexcom_driver); + +MODULE_ALIAS("platform:at91_flexcom"); +MODULE_DESCRIPTION("Atmel AT91 Flexcom driver"); +MODULE_AUTHOR("Cyrille Pitchen <cyrille.pitchen@atmel.com>"); +MODULE_LICENSE("GPL v2"); +
Signed-off-by: Cyrille Pitchen <cyrille.pitchen@atmel.com> This driver supports the new Atmel Flexcom. The Flexcom is a wrapper which integrates one SPI controller, one I2C controller and one USART. Only one function can be enabled at a time. This driver selects the function once for all, when the Flexcom is probed, according to the value of the new "atmel,flexcom-mode" device tree property. This driver has chosen to present the Flexcom to the system as a clock so the implementation is seamless for the existing Atmel SPI, I2C and USART drivers. Also the Flexcom embeds FIFOs: the latest patches of the SPI, I2C and USART drivers take advantage of this new feature. Conflicts: drivers/clk/at91/Makefile --- arch/arm/mach-at91/Kconfig | 3 + drivers/clk/at91/Makefile | 1 + drivers/clk/at91/clk-flexcom.c | 160 +++++++++++++++++++++++++++++++++++++++++ 3 files changed, 164 insertions(+) create mode 100644 drivers/clk/at91/clk-flexcom.c