| Message ID | 20241217133713.326853-3-alexander.sverdlin@siemens.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | leds: TI LP8864/LP8866 support | expand |
On 12/17/24 7:37 AM, A. Sverdlin wrote: > From: Alexander Sverdlin <alexander.sverdlin@siemens.com> > > Add driver for TI LP8864, LP8864S, LP8866 4/6 channel LED-backlight drivers > with I2C interface. > > Link: https://www.ti.com/lit/gpn/lp8864-q1 > Link: https://www.ti.com/lit/gpn/lp8864s-q1 > Link: https://www.ti.com/lit/gpn/lp8866-q1 > Link: https://www.ti.com/lit/gpn/lp8866s-q1 > Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com> > --- > Changelog: > v4: > - better separated comments from register defines > - removed NULL from fault text arrays for two regs with odd-even structure > - changed HW fault printf from errors to warnings > - renamed "buf" -> "val" > - reflowed the code with up to 100 symbols per line > - added comments for 8<->16-bit linear scaling in set/get callbacks > - removed register names from error messages > v3: > - dropped lp8864_init(), REGCACHE_NONE, %pe in dev_err_probe(), > i2c_set_clientdata() > - added devm_add_action_or_reset() return value check, dev_err_probe() after > devm_regmap_init_i2c() > v2: no changes > > MAINTAINERS | 7 + > drivers/leds/Kconfig | 12 ++ > drivers/leds/Makefile | 1 + > drivers/leds/leds-lp8864.c | 296 +++++++++++++++++++++++++++++++++++++ > 4 files changed, 316 insertions(+) > create mode 100644 drivers/leds/leds-lp8864.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index b332995b3350..d4268a3bbc5a 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -23322,6 +23322,13 @@ S: Supported > F: Documentation/devicetree/bindings/iio/dac/ti,dac7612.yaml > F: drivers/iio/dac/ti-dac7612.c > > +TEXAS INSTRUMENTS' LB8864 LED BACKLIGHT DRIVER > +M: Alexander Sverdlin <alexander.sverdlin@siemens.com> > +L: linux-leds@vger.kernel.org > +S: Maintained > +F: Documentation/devicetree/bindings/leds/backlight/ti,lp8864.yaml > +F: drivers/leds/leds-lp8864.c > + > TEXAS INSTRUMENTS' SYSTEM CONTROL INTERFACE (TISCI) PROTOCOL DRIVER > M: Nishanth Menon <nm@ti.com> > M: Tero Kristo <kristo@kernel.org> > diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig > index 3bf51a4e01d7..5dde8f46100c 100644 > --- a/drivers/leds/Kconfig > +++ b/drivers/leds/Kconfig > @@ -513,6 +513,18 @@ config LEDS_LP8860 > on the LP8860 4 channel LED driver using the I2C communication > bus. > > +config LEDS_LP8864 > + tristate "LED support for the TI LP8864/LP8866 4/6 channel LED drivers" > + depends on LEDS_CLASS && I2C && OF > + select REGMAP_I2C > + help > + If you say yes here you get support for the TI LP8864-Q1, > + LP8864S-Q1, LP8866-Q1, LP8866S-Q1 4/6 channel LED backlight > + drivers with I2C interface. > + > + To compile this driver as a module, choose M here: the > + module will be called leds-lp8864. > + > config LEDS_CLEVO_MAIL > tristate "Mail LED on Clevo notebook" > depends on LEDS_CLASS && BROKEN > diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile > index e7982938ddc1..8a2caa48343b 100644 > --- a/drivers/leds/Makefile > +++ b/drivers/leds/Makefile > @@ -57,6 +57,7 @@ obj-$(CONFIG_LEDS_LP55XX_COMMON) += leds-lp55xx-common.o > obj-$(CONFIG_LEDS_LP8501) += leds-lp8501.o > obj-$(CONFIG_LEDS_LP8788) += leds-lp8788.o > obj-$(CONFIG_LEDS_LP8860) += leds-lp8860.o > +obj-$(CONFIG_LEDS_LP8864) += leds-lp8864.o > obj-$(CONFIG_LEDS_LT3593) += leds-lt3593.o > obj-$(CONFIG_LEDS_MAX5970) += leds-max5970.o > obj-$(CONFIG_LEDS_MAX77650) += leds-max77650.o > diff --git a/drivers/leds/leds-lp8864.c b/drivers/leds/leds-lp8864.c > new file mode 100644 > index 000000000000..9ee9e5e0df3c > --- /dev/null > +++ b/drivers/leds/leds-lp8864.c > @@ -0,0 +1,296 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * TI LP8864/LP8866 4/6 Channel LED Driver > + * > + * Copyright (C) 2024 Siemens AG > + * > + * Based on LP8860 driver by Dan Murphy <dmurphy@ti.com> > + */ > + > +#include <linux/gpio/consumer.h> > +#include <linux/i2c.h> > +#include <linux/init.h> > +#include <linux/leds.h> > +#include <linux/module.h> > +#include <linux/mutex.h> > +#include <linux/of.h> > +#include <linux/regmap.h> > +#include <linux/regulator/consumer.h> > +#include <linux/slab.h> > + > +#define LP8864_BRT_CONTROL 0x00 > +#define LP8864_USER_CONFIG1 0x04 > +#define LP8864_BRT_MODE_MASK GENMASK(9, 8) > +#define LP8864_BRT_MODE_REG BIT(9) /* Brightness control by DISPLAY_BRT reg */ > +#define LP8864_SUPPLY_STATUS 0x0e > +#define LP8864_BOOST_STATUS 0x10 > +#define LP8864_LED_STATUS 0x12 > +#define LP8864_LED_STATUS_WR_MASK GENMASK(14, 9 /* Writeable bits in the LED_STATUS reg */ Missing the closing ) ? > + > +/* Textual meaning for status bits, starting from bit 1 */ > +static const char *const lp8864_supply_status_msg[] = { > + "Vin under-voltage fault", > + "Vin over-voltage fault", > + "Vdd under-voltage fault", > + "Vin over-current fault", > + "Missing charge pump fault", > + "Charge pump fault", > + "Missing boost sync fault", > + "CRC error fault ", > +}; > + > +/* Textual meaning for status bits, starting from bit 1 */ > +static const char *const lp8864_boost_status_msg[] = { > + "Boost OVP low fault", > + "Boost OVP high fault", > + "Boost over-current fault", > + "Missing boost FSET resistor fault", > + "Missing MODE SEL resistor fault", > + "Missing LED resistor fault", > + "ISET resistor short to ground fault", > + "Thermal shutdown fault", > +}; > + > +/* Textual meaning for every register bit */ > +static const char *const lp8864_led_status_msg[] = { > + "LED 1 fault", > + "LED 2 fault", > + "LED 3 fault", > + "LED 4 fault", > + "LED 5 fault", > + "LED 6 fault", > + "LED open fault", > + "LED internal short fault", > + "LED short to GND fault", > + NULL, NULL, NULL, > + "Invalid string configuration fault", > + NULL, > + "I2C time out fault", > +}; > + > +/** > + * struct lp8864_led > + * @client: Pointer to the I2C client > + * @led_dev: led class device pointer > + * @regmap: Devices register map > + * @led_status_mask: Helps to report LED fault only once > + */ > +struct lp8864_led { > + struct i2c_client *client; > + struct led_classdev led_dev; > + struct regmap *regmap; > + u16 led_status_mask; > +}; > + > +static int lp8864_fault_check(struct lp8864_led *led) > +{ > + int ret, i; > + unsigned int val; > + > + ret = regmap_read(led->regmap, LP8864_SUPPLY_STATUS, &val); > + if (ret) > + goto err; You could probably keep this simple and print the exact error here and return, vs the common error message at the end > + > + /* Odd bits are status bits, even bits are clear bits */ > + for (i = 0; i < ARRAY_SIZE(lp8864_supply_status_msg); i++) > + if (val & BIT(i * 2 + 1)) > + dev_warn(&led->client->dev, "%s\n", lp8864_supply_status_msg[i]); > + > + /* > + * Clear bits have an index preceding the corresponding Status bits; > + * both have to be written "1" simultaneously to clear the corresponding > + * Status bit. > + */ > + if (val) > + ret = regmap_write(led->regmap, LP8864_SUPPLY_STATUS, val >> 1 | val); > + if (ret) > + goto err; > + > + ret = regmap_read(led->regmap, LP8864_BOOST_STATUS, &val); > + if (ret) > + goto err; > + > + /* Odd bits are status bits, even bits are clear bits */ > + for (i = 0; i < ARRAY_SIZE(lp8864_boost_status_msg); i++) > + if (val & BIT(i * 2 + 1)) > + dev_warn(&led->client->dev, "%s\n", lp8864_boost_status_msg[i]); > + > + if (val) > + ret = regmap_write(led->regmap, LP8864_BOOST_STATUS, val >> 1 | val); > + if (ret) > + goto err; > + > + ret = regmap_read(led->regmap, LP8864_LED_STATUS, &val); > + if (ret) > + goto err; > + > + /* > + * Clear already reported faults that maintain their value until device > + * power-down > + */ > + val &= ~led->led_status_mask; > + > + for (i = 0; i < ARRAY_SIZE(lp8864_led_status_msg); i++) > + if (lp8864_led_status_msg[i] && val & BIT(i)) > + dev_warn(&led->client->dev, "%s\n", lp8864_led_status_msg[i]); > + > + /* > + * Mark those which maintain their value until device power-down as > + * "already reported" > + */ > + led->led_status_mask |= val & ~LP8864_LED_STATUS_WR_MASK; > + > + /* > + * Only bits 14, 12, 10 have to be cleared here, but others are RO, > + * we don't care what we write to them. > + */ > + if (val & LP8864_LED_STATUS_WR_MASK) > + ret = regmap_write(led->regmap, LP8864_LED_STATUS, val >> 1 | val); > + if (ret) > + goto err; > + > + return 0; > + > +err: > + dev_err(&led->client->dev, "Failed to read/clear faults (%pe)\n", ERR_PTR(ret)); > + > + return ret; > +} > + > +static int lp8864_brightness_set(struct led_classdev *led_cdev, > + enum led_brightness brt_val) > +{ > + struct lp8864_led *led = container_of(led_cdev, struct lp8864_led, led_dev); > + /* Scale 0..LED_FULL into 16-bit HW brightness */ > + unsigned int val = brt_val * 0xffff / LED_FULL; > + int ret; > + > + ret = lp8864_fault_check(led); > + if (ret) > + return ret; > + > + ret = regmap_write(led->regmap, LP8864_BRT_CONTROL, val); > + if (ret) > + dev_err(&led->client->dev, "Failed to write brightness value\n"); > + > + return ret; > +} > + > +static enum led_brightness lp8864_brightness_get(struct led_classdev *led_cdev) > +{ > + struct lp8864_led *led = container_of(led_cdev, struct lp8864_led, led_dev); > + unsigned int val; > + int ret; > + > + ret = regmap_read(led->regmap, LP8864_BRT_CONTROL, &val); > + if (ret) { > + dev_err(&led->client->dev, "Failed to read brightness value\n"); > + return ret; > + } > + > + /* Scale 16-bit HW brightness into 0..LED_FULL */ > + return val * LED_FULL / 0xffff; > +} > + > +static const struct regmap_config lp8864_regmap_config = { > + .reg_bits = 8, > + .val_bits = 16, > + .val_format_endian = REGMAP_ENDIAN_LITTLE, > +}; > + > +static void lp8864_disable_gpio(void *data) > +{ > + struct gpio_desc *gpio = data; > + > + gpiod_set_value(gpio, 0); > +} > + > +static int lp8864_probe(struct i2c_client *client) > +{ > + int ret; > + struct lp8864_led *led; > + struct device_node *np = dev_of_node(&client->dev); > + struct device_node *child_node; > + struct led_init_data init_data = {}; > + struct gpio_desc *enable_gpio; > + > + led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL); > + if (!led) > + return -ENOMEM; > + > + child_node = of_get_next_available_child(np, NULL); > + if (!child_node) { > + dev_err(&client->dev, "No LED function defined\n"); > + return -EINVAL; > + } > + > + ret = devm_regulator_get_enable_optional(&client->dev, "vled"); > + if (ret && ret != -ENODEV) > + return dev_err_probe(&client->dev, ret, "Failed to enable vled regulator\n"); > + > + enable_gpio = devm_gpiod_get_optional(&client->dev, "enable", GPIOD_OUT_HIGH); > + if (IS_ERR(enable_gpio)) > + return dev_err_probe(&client->dev, PTR_ERR(enable_gpio), > + "Failed to get enable GPIO\n"); > + > + ret = devm_add_action_or_reset(&client->dev, lp8864_disable_gpio, enable_gpio); > + if (ret) > + return ret; > + > + led->client = client; > + led->led_dev.brightness_set_blocking = lp8864_brightness_set; > + led->led_dev.brightness_get = lp8864_brightness_get; > + > + led->regmap = devm_regmap_init_i2c(client, &lp8864_regmap_config); > + if (IS_ERR(led->regmap)) > + return dev_err_probe(&client->dev, PTR_ERR(led->regmap), > + "Failed to allocate regmap\n"); > + > + /* Control brightness by DISPLAY_BRT register */ > + ret = regmap_update_bits(led->regmap, LP8864_USER_CONFIG1, LP8864_BRT_MODE_MASK, > + LP8864_BRT_MODE_REG); > + if (ret) { > + dev_err(&led->client->dev, "Failed to set brightness control mode\n"); > + return ret; > + } > + > + ret = lp8864_fault_check(led); > + if (ret) > + return ret; > + > + init_data.fwnode = of_fwnode_handle(child_node); > + init_data.devicename = "lp8864"; > + init_data.default_label = ":display_cluster"; > + > + ret = devm_led_classdev_register_ext(&client->dev, &led->led_dev, &init_data); > + if (ret) > + dev_err(&client->dev, "Failed to register LED device (%pe)\n", ERR_PTR(ret)); > + > + return ret; > +} > + > +static const struct i2c_device_id lp8864_id[] = { > + { "lp8864" }, > + {} > +}; > +MODULE_DEVICE_TABLE(i2c, lp8864_id); > + > +static const struct of_device_id of_lp8864_leds_match[] = { > + { .compatible = "ti,lp8864" }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, of_lp8864_leds_match); > + > +static struct i2c_driver lp8864_driver = { > + .driver = { > + .name = "lp8864", > + .of_match_table = of_lp8864_leds_match, > + }, > + .probe = lp8864_probe, > + .id_table = lp8864_id, > +}; > +module_i2c_driver(lp8864_driver); > + > +MODULE_DESCRIPTION("Texas Instruments LP8864/LP8866 LED driver"); > +MODULE_AUTHOR("Alexander Sverdlin <alexander.sverdlin@siemens.com>"); > +MODULE_LICENSE("GPL");
Hi Andrew! On Tue, 2024-12-17 at 09:56 -0600, Andrew Davis wrote: > On 12/17/24 7:37 AM, A. Sverdlin wrote: > > From: Alexander Sverdlin <alexander.sverdlin@siemens.com> > > > > Add driver for TI LP8864, LP8864S, LP8866 4/6 channel LED-backlight drivers > > with I2C interface. > > > > Link: https://www.ti.com/lit/gpn/lp8864-q1 > > Link: https://www.ti.com/lit/gpn/lp8864s-q1 > > Link: https://www.ti.com/lit/gpn/lp8866-q1 > > Link: https://www.ti.com/lit/gpn/lp8866s-q1 > > Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com> > > --- > > Changelog: > > v4: > > - better separated comments from register defines > > - removed NULL from fault text arrays for two regs with odd-even structure > > - changed HW fault printf from errors to warnings > > - renamed "buf" -> "val" > > - reflowed the code with up to 100 symbols per line > > - added comments for 8<->16-bit linear scaling in set/get callbacks > > - removed register names from error messages > > v3: > > - dropped lp8864_init(), REGCACHE_NONE, %pe in dev_err_probe(), > > i2c_set_clientdata() > > - added devm_add_action_or_reset() return value check, dev_err_probe() after > > devm_regmap_init_i2c() > > v2: no changes > > > > MAINTAINERS | 7 + > > drivers/leds/Kconfig | 12 ++ > > drivers/leds/Makefile | 1 + > > drivers/leds/leds-lp8864.c | 296 +++++++++++++++++++++++++++++++++++++ > > 4 files changed, 316 insertions(+) > > create mode 100644 drivers/leds/leds-lp8864.c > > > > diff --git a/MAINTAINERS b/MAINTAINERS > > index b332995b3350..d4268a3bbc5a 100644 > > --- a/MAINTAINERS > > +++ b/MAINTAINERS > > @@ -23322,6 +23322,13 @@ S: Supported > > F: Documentation/devicetree/bindings/iio/dac/ti,dac7612.yaml > > F: drivers/iio/dac/ti-dac7612.c > > > > +TEXAS INSTRUMENTS' LB8864 LED BACKLIGHT DRIVER > > +M: Alexander Sverdlin <alexander.sverdlin@siemens.com> > > +L: linux-leds@vger.kernel.org > > +S: Maintained > > +F: Documentation/devicetree/bindings/leds/backlight/ti,lp8864.yaml > > +F: drivers/leds/leds-lp8864.c > > + > > TEXAS INSTRUMENTS' SYSTEM CONTROL INTERFACE (TISCI) PROTOCOL DRIVER > > M: Nishanth Menon <nm@ti.com> > > M: Tero Kristo <kristo@kernel.org> > > diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig > > index 3bf51a4e01d7..5dde8f46100c 100644 > > --- a/drivers/leds/Kconfig > > +++ b/drivers/leds/Kconfig > > @@ -513,6 +513,18 @@ config LEDS_LP8860 > > on the LP8860 4 channel LED driver using the I2C communication > > bus. > > > > +config LEDS_LP8864 > > + tristate "LED support for the TI LP8864/LP8866 4/6 channel LED drivers" > > + depends on LEDS_CLASS && I2C && OF > > + select REGMAP_I2C > > + help > > + If you say yes here you get support for the TI LP8864-Q1, > > + LP8864S-Q1, LP8866-Q1, LP8866S-Q1 4/6 channel LED backlight > > + drivers with I2C interface. > > + > > + To compile this driver as a module, choose M here: the > > + module will be called leds-lp8864. > > + > > config LEDS_CLEVO_MAIL > > tristate "Mail LED on Clevo notebook" > > depends on LEDS_CLASS && BROKEN > > diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile > > index e7982938ddc1..8a2caa48343b 100644 > > --- a/drivers/leds/Makefile > > +++ b/drivers/leds/Makefile > > @@ -57,6 +57,7 @@ obj-$(CONFIG_LEDS_LP55XX_COMMON) += leds-lp55xx-common.o > > obj-$(CONFIG_LEDS_LP8501) += leds-lp8501.o > > obj-$(CONFIG_LEDS_LP8788) += leds-lp8788.o > > obj-$(CONFIG_LEDS_LP8860) += leds-lp8860.o > > +obj-$(CONFIG_LEDS_LP8864) += leds-lp8864.o > > obj-$(CONFIG_LEDS_LT3593) += leds-lt3593.o > > obj-$(CONFIG_LEDS_MAX5970) += leds-max5970.o > > obj-$(CONFIG_LEDS_MAX77650) += leds-max77650.o > > diff --git a/drivers/leds/leds-lp8864.c b/drivers/leds/leds-lp8864.c > > new file mode 100644 > > index 000000000000..9ee9e5e0df3c > > --- /dev/null > > +++ b/drivers/leds/leds-lp8864.c > > @@ -0,0 +1,296 @@ > > +// SPDX-License-Identifier: GPL-2.0-only > > +/* > > + * TI LP8864/LP8866 4/6 Channel LED Driver > > + * > > + * Copyright (C) 2024 Siemens AG > > + * > > + * Based on LP8860 driver by Dan Murphy <dmurphy@ti.com> > > + */ > > + > > +#include <linux/gpio/consumer.h> > > +#include <linux/i2c.h> > > +#include <linux/init.h> > > +#include <linux/leds.h> > > +#include <linux/module.h> > > +#include <linux/mutex.h> > > +#include <linux/of.h> > > +#include <linux/regmap.h> > > +#include <linux/regulator/consumer.h> > > +#include <linux/slab.h> > > + > > +#define LP8864_BRT_CONTROL 0x00 > > +#define LP8864_USER_CONFIG1 0x04 > > +#define LP8864_BRT_MODE_MASK GENMASK(9, 8) > > +#define LP8864_BRT_MODE_REG BIT(9) /* Brightness control by DISPLAY_BRT reg */ > > +#define LP8864_SUPPLY_STATUS 0x0e > > +#define LP8864_BOOST_STATUS 0x10 > > +#define LP8864_LED_STATUS 0x12 > > +#define LP8864_LED_STATUS_WR_MASK GENMASK(14, 9 /* Writeable bits in the LED_STATUS reg */ > > Missing the closing ) ? Thanks for the review! Seems that my testing went seriously wrong :[ ]
diff --git a/MAINTAINERS b/MAINTAINERS index b332995b3350..d4268a3bbc5a 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -23322,6 +23322,13 @@ S: Supported F: Documentation/devicetree/bindings/iio/dac/ti,dac7612.yaml F: drivers/iio/dac/ti-dac7612.c +TEXAS INSTRUMENTS' LB8864 LED BACKLIGHT DRIVER +M: Alexander Sverdlin <alexander.sverdlin@siemens.com> +L: linux-leds@vger.kernel.org +S: Maintained +F: Documentation/devicetree/bindings/leds/backlight/ti,lp8864.yaml +F: drivers/leds/leds-lp8864.c + TEXAS INSTRUMENTS' SYSTEM CONTROL INTERFACE (TISCI) PROTOCOL DRIVER M: Nishanth Menon <nm@ti.com> M: Tero Kristo <kristo@kernel.org> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index 3bf51a4e01d7..5dde8f46100c 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -513,6 +513,18 @@ config LEDS_LP8860 on the LP8860 4 channel LED driver using the I2C communication bus. +config LEDS_LP8864 + tristate "LED support for the TI LP8864/LP8866 4/6 channel LED drivers" + depends on LEDS_CLASS && I2C && OF + select REGMAP_I2C + help + If you say yes here you get support for the TI LP8864-Q1, + LP8864S-Q1, LP8866-Q1, LP8866S-Q1 4/6 channel LED backlight + drivers with I2C interface. + + To compile this driver as a module, choose M here: the + module will be called leds-lp8864. + config LEDS_CLEVO_MAIL tristate "Mail LED on Clevo notebook" depends on LEDS_CLASS && BROKEN diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index e7982938ddc1..8a2caa48343b 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -57,6 +57,7 @@ obj-$(CONFIG_LEDS_LP55XX_COMMON) += leds-lp55xx-common.o obj-$(CONFIG_LEDS_LP8501) += leds-lp8501.o obj-$(CONFIG_LEDS_LP8788) += leds-lp8788.o obj-$(CONFIG_LEDS_LP8860) += leds-lp8860.o +obj-$(CONFIG_LEDS_LP8864) += leds-lp8864.o obj-$(CONFIG_LEDS_LT3593) += leds-lt3593.o obj-$(CONFIG_LEDS_MAX5970) += leds-max5970.o obj-$(CONFIG_LEDS_MAX77650) += leds-max77650.o diff --git a/drivers/leds/leds-lp8864.c b/drivers/leds/leds-lp8864.c new file mode 100644 index 000000000000..9ee9e5e0df3c --- /dev/null +++ b/drivers/leds/leds-lp8864.c @@ -0,0 +1,296 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * TI LP8864/LP8866 4/6 Channel LED Driver + * + * Copyright (C) 2024 Siemens AG + * + * Based on LP8860 driver by Dan Murphy <dmurphy@ti.com> + */ + +#include <linux/gpio/consumer.h> +#include <linux/i2c.h> +#include <linux/init.h> +#include <linux/leds.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/of.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> +#include <linux/slab.h> + +#define LP8864_BRT_CONTROL 0x00 +#define LP8864_USER_CONFIG1 0x04 +#define LP8864_BRT_MODE_MASK GENMASK(9, 8) +#define LP8864_BRT_MODE_REG BIT(9) /* Brightness control by DISPLAY_BRT reg */ +#define LP8864_SUPPLY_STATUS 0x0e +#define LP8864_BOOST_STATUS 0x10 +#define LP8864_LED_STATUS 0x12 +#define LP8864_LED_STATUS_WR_MASK GENMASK(14, 9 /* Writeable bits in the LED_STATUS reg */ + +/* Textual meaning for status bits, starting from bit 1 */ +static const char *const lp8864_supply_status_msg[] = { + "Vin under-voltage fault", + "Vin over-voltage fault", + "Vdd under-voltage fault", + "Vin over-current fault", + "Missing charge pump fault", + "Charge pump fault", + "Missing boost sync fault", + "CRC error fault ", +}; + +/* Textual meaning for status bits, starting from bit 1 */ +static const char *const lp8864_boost_status_msg[] = { + "Boost OVP low fault", + "Boost OVP high fault", + "Boost over-current fault", + "Missing boost FSET resistor fault", + "Missing MODE SEL resistor fault", + "Missing LED resistor fault", + "ISET resistor short to ground fault", + "Thermal shutdown fault", +}; + +/* Textual meaning for every register bit */ +static const char *const lp8864_led_status_msg[] = { + "LED 1 fault", + "LED 2 fault", + "LED 3 fault", + "LED 4 fault", + "LED 5 fault", + "LED 6 fault", + "LED open fault", + "LED internal short fault", + "LED short to GND fault", + NULL, NULL, NULL, + "Invalid string configuration fault", + NULL, + "I2C time out fault", +}; + +/** + * struct lp8864_led + * @client: Pointer to the I2C client + * @led_dev: led class device pointer + * @regmap: Devices register map + * @led_status_mask: Helps to report LED fault only once + */ +struct lp8864_led { + struct i2c_client *client; + struct led_classdev led_dev; + struct regmap *regmap; + u16 led_status_mask; +}; + +static int lp8864_fault_check(struct lp8864_led *led) +{ + int ret, i; + unsigned int val; + + ret = regmap_read(led->regmap, LP8864_SUPPLY_STATUS, &val); + if (ret) + goto err; + + /* Odd bits are status bits, even bits are clear bits */ + for (i = 0; i < ARRAY_SIZE(lp8864_supply_status_msg); i++) + if (val & BIT(i * 2 + 1)) + dev_warn(&led->client->dev, "%s\n", lp8864_supply_status_msg[i]); + + /* + * Clear bits have an index preceding the corresponding Status bits; + * both have to be written "1" simultaneously to clear the corresponding + * Status bit. + */ + if (val) + ret = regmap_write(led->regmap, LP8864_SUPPLY_STATUS, val >> 1 | val); + if (ret) + goto err; + + ret = regmap_read(led->regmap, LP8864_BOOST_STATUS, &val); + if (ret) + goto err; + + /* Odd bits are status bits, even bits are clear bits */ + for (i = 0; i < ARRAY_SIZE(lp8864_boost_status_msg); i++) + if (val & BIT(i * 2 + 1)) + dev_warn(&led->client->dev, "%s\n", lp8864_boost_status_msg[i]); + + if (val) + ret = regmap_write(led->regmap, LP8864_BOOST_STATUS, val >> 1 | val); + if (ret) + goto err; + + ret = regmap_read(led->regmap, LP8864_LED_STATUS, &val); + if (ret) + goto err; + + /* + * Clear already reported faults that maintain their value until device + * power-down + */ + val &= ~led->led_status_mask; + + for (i = 0; i < ARRAY_SIZE(lp8864_led_status_msg); i++) + if (lp8864_led_status_msg[i] && val & BIT(i)) + dev_warn(&led->client->dev, "%s\n", lp8864_led_status_msg[i]); + + /* + * Mark those which maintain their value until device power-down as + * "already reported" + */ + led->led_status_mask |= val & ~LP8864_LED_STATUS_WR_MASK; + + /* + * Only bits 14, 12, 10 have to be cleared here, but others are RO, + * we don't care what we write to them. + */ + if (val & LP8864_LED_STATUS_WR_MASK) + ret = regmap_write(led->regmap, LP8864_LED_STATUS, val >> 1 | val); + if (ret) + goto err; + + return 0; + +err: + dev_err(&led->client->dev, "Failed to read/clear faults (%pe)\n", ERR_PTR(ret)); + + return ret; +} + +static int lp8864_brightness_set(struct led_classdev *led_cdev, + enum led_brightness brt_val) +{ + struct lp8864_led *led = container_of(led_cdev, struct lp8864_led, led_dev); + /* Scale 0..LED_FULL into 16-bit HW brightness */ + unsigned int val = brt_val * 0xffff / LED_FULL; + int ret; + + ret = lp8864_fault_check(led); + if (ret) + return ret; + + ret = regmap_write(led->regmap, LP8864_BRT_CONTROL, val); + if (ret) + dev_err(&led->client->dev, "Failed to write brightness value\n"); + + return ret; +} + +static enum led_brightness lp8864_brightness_get(struct led_classdev *led_cdev) +{ + struct lp8864_led *led = container_of(led_cdev, struct lp8864_led, led_dev); + unsigned int val; + int ret; + + ret = regmap_read(led->regmap, LP8864_BRT_CONTROL, &val); + if (ret) { + dev_err(&led->client->dev, "Failed to read brightness value\n"); + return ret; + } + + /* Scale 16-bit HW brightness into 0..LED_FULL */ + return val * LED_FULL / 0xffff; +} + +static const struct regmap_config lp8864_regmap_config = { + .reg_bits = 8, + .val_bits = 16, + .val_format_endian = REGMAP_ENDIAN_LITTLE, +}; + +static void lp8864_disable_gpio(void *data) +{ + struct gpio_desc *gpio = data; + + gpiod_set_value(gpio, 0); +} + +static int lp8864_probe(struct i2c_client *client) +{ + int ret; + struct lp8864_led *led; + struct device_node *np = dev_of_node(&client->dev); + struct device_node *child_node; + struct led_init_data init_data = {}; + struct gpio_desc *enable_gpio; + + led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL); + if (!led) + return -ENOMEM; + + child_node = of_get_next_available_child(np, NULL); + if (!child_node) { + dev_err(&client->dev, "No LED function defined\n"); + return -EINVAL; + } + + ret = devm_regulator_get_enable_optional(&client->dev, "vled"); + if (ret && ret != -ENODEV) + return dev_err_probe(&client->dev, ret, "Failed to enable vled regulator\n"); + + enable_gpio = devm_gpiod_get_optional(&client->dev, "enable", GPIOD_OUT_HIGH); + if (IS_ERR(enable_gpio)) + return dev_err_probe(&client->dev, PTR_ERR(enable_gpio), + "Failed to get enable GPIO\n"); + + ret = devm_add_action_or_reset(&client->dev, lp8864_disable_gpio, enable_gpio); + if (ret) + return ret; + + led->client = client; + led->led_dev.brightness_set_blocking = lp8864_brightness_set; + led->led_dev.brightness_get = lp8864_brightness_get; + + led->regmap = devm_regmap_init_i2c(client, &lp8864_regmap_config); + if (IS_ERR(led->regmap)) + return dev_err_probe(&client->dev, PTR_ERR(led->regmap), + "Failed to allocate regmap\n"); + + /* Control brightness by DISPLAY_BRT register */ + ret = regmap_update_bits(led->regmap, LP8864_USER_CONFIG1, LP8864_BRT_MODE_MASK, + LP8864_BRT_MODE_REG); + if (ret) { + dev_err(&led->client->dev, "Failed to set brightness control mode\n"); + return ret; + } + + ret = lp8864_fault_check(led); + if (ret) + return ret; + + init_data.fwnode = of_fwnode_handle(child_node); + init_data.devicename = "lp8864"; + init_data.default_label = ":display_cluster"; + + ret = devm_led_classdev_register_ext(&client->dev, &led->led_dev, &init_data); + if (ret) + dev_err(&client->dev, "Failed to register LED device (%pe)\n", ERR_PTR(ret)); + + return ret; +} + +static const struct i2c_device_id lp8864_id[] = { + { "lp8864" }, + {} +}; +MODULE_DEVICE_TABLE(i2c, lp8864_id); + +static const struct of_device_id of_lp8864_leds_match[] = { + { .compatible = "ti,lp8864" }, + {} +}; +MODULE_DEVICE_TABLE(of, of_lp8864_leds_match); + +static struct i2c_driver lp8864_driver = { + .driver = { + .name = "lp8864", + .of_match_table = of_lp8864_leds_match, + }, + .probe = lp8864_probe, + .id_table = lp8864_id, +}; +module_i2c_driver(lp8864_driver); + +MODULE_DESCRIPTION("Texas Instruments LP8864/LP8866 LED driver"); +MODULE_AUTHOR("Alexander Sverdlin <alexander.sverdlin@siemens.com>"); +MODULE_LICENSE("GPL");