diff options
author | Lee Jones <lee@kernel.org> | 2024-03-07 11:47:13 +0300 |
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committer | Lee Jones <lee@kernel.org> | 2024-03-07 11:47:13 +0300 |
commit | 888cd6e721558a818f9900a98744088f5fca3f5c (patch) | |
tree | 0eabb137032db8aa2bd5e7b0349e87ee230279ac | |
parent | 5b2dd77be1d85ac3a8be3749f5605bf0830e2998 (diff) | |
parent | 7774f3d1dd3822e938e236df67766436c0debd11 (diff) | |
download | linux-888cd6e721558a818f9900a98744088f5fca3f5c.tar.xz |
Merge branches 'ib-qcom-leds-6.9' and 'ib-leds-backlight-6.9' into ibs-for-leds-merged
-rw-r--r-- | Documentation/devicetree/bindings/leds/backlight/kinetic,ktd2801.yaml | 46 | ||||
-rw-r--r-- | MAINTAINERS | 13 | ||||
-rw-r--r-- | drivers/leds/Kconfig | 4 | ||||
-rw-r--r-- | drivers/leds/Makefile | 3 | ||||
-rw-r--r-- | drivers/leds/flash/Kconfig | 3 | ||||
-rw-r--r-- | drivers/leds/flash/leds-ktd2692.c | 116 | ||||
-rw-r--r-- | drivers/leds/leds-expresswire.c | 72 | ||||
-rw-r--r-- | drivers/video/backlight/Kconfig | 7 | ||||
-rw-r--r-- | drivers/video/backlight/Makefile | 1 | ||||
-rw-r--r-- | drivers/video/backlight/ktd2801-backlight.c | 128 | ||||
-rw-r--r-- | include/linux/leds-expresswire.h | 38 |
11 files changed, 341 insertions, 90 deletions
diff --git a/Documentation/devicetree/bindings/leds/backlight/kinetic,ktd2801.yaml b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktd2801.yaml new file mode 100644 index 000000000000..b005065e0f48 --- /dev/null +++ b/Documentation/devicetree/bindings/leds/backlight/kinetic,ktd2801.yaml @@ -0,0 +1,46 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/leds/backlight/kinetic,ktd2801.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Kinetic Technologies KTD2801 one-wire backlight + +maintainers: + - Duje Mihanović <duje.mihanovic@skole.hr> + +description: | + The Kinetic Technologies KTD2801 is a LED backlight driver controlled + by a single GPIO line. The driver can be controlled with a PWM signal + or by pulsing the GPIO line to set the backlight level. This is called + "ExpressWire". + +allOf: + - $ref: common.yaml# + +properties: + compatible: + const: kinetic,ktd2801 + + ctrl-gpios: + maxItems: 1 + + default-brightness: true + max-brightness: true + +required: + - compatible + - ctrl-gpios + +additionalProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + + backlight { + compatible = "kinetic,ktd2801"; + ctrl-gpios = <&gpio 97 GPIO_ACTIVE_HIGH>; + max-brightness = <210>; + default-brightness = <100>; + }; diff --git a/MAINTAINERS b/MAINTAINERS index 8d1052fa6a69..01cd1a460907 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7979,6 +7979,13 @@ S: Maintained T: git git://git.kernel.org/pub/scm/linux/kernel/git/linkinjeon/exfat.git F: fs/exfat/ +EXPRESSWIRE PROTOCOL LIBRARY +M: Duje Mihanović <duje.mihanovic@skole.hr> +L: linux-leds@vger.kernel.org +S: Maintained +F: drivers/leds/leds-expresswire.c +F: include/linux/leds-expresswire.h + EXT2 FILE SYSTEM M: Jan Kara <jack@suse.com> L: linux-ext4@vger.kernel.org @@ -12045,6 +12052,12 @@ S: Maintained F: Documentation/devicetree/bindings/leds/backlight/kinetic,ktd253.yaml F: drivers/video/backlight/ktd253-backlight.c +KTD2801 BACKLIGHT DRIVER +M: Duje Mihanović <duje.mihanovic@skole.hr> +S: Maintained +F: Documentation/devicetree/bindings/leds/backlight/kinetic,ktd2801.yaml +F: drivers/video/backlight/ktd2801-backlight.c + KTEST M: Steven Rostedt <rostedt@goodmis.org> M: John Hawley <warthog9@eaglescrag.net> diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig index d721b254e1e4..64bb2de237e9 100644 --- a/drivers/leds/Kconfig +++ b/drivers/leds/Kconfig @@ -186,6 +186,10 @@ config LEDS_EL15203000 To compile this driver as a module, choose M here: the module will be called leds-el15203000. +config LEDS_EXPRESSWIRE + bool + depends on GPIOLIB + config LEDS_TURRIS_OMNIA tristate "LED support for CZ.NIC's Turris Omnia" depends on LEDS_CLASS_MULTICOLOR diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile index ce07dc295ff0..effdfc6f1e95 100644 --- a/drivers/leds/Makefile +++ b/drivers/leds/Makefile @@ -91,6 +91,9 @@ obj-$(CONFIG_LEDS_WM831X_STATUS) += leds-wm831x-status.o obj-$(CONFIG_LEDS_WM8350) += leds-wm8350.o obj-$(CONFIG_LEDS_WRAP) += leds-wrap.o +# Kinetic ExpressWire Protocol +obj-$(CONFIG_LEDS_EXPRESSWIRE) += leds-expresswire.o + # LED SPI Drivers obj-$(CONFIG_LEDS_CR0014114) += leds-cr0014114.o obj-$(CONFIG_LEDS_DAC124S085) += leds-dac124s085.o diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig index 4e08dbc05709..24722d581369 100644 --- a/drivers/leds/flash/Kconfig +++ b/drivers/leds/flash/Kconfig @@ -23,7 +23,8 @@ config LEDS_AS3645A config LEDS_KTD2692 tristate "LED support for Kinetic KTD2692 flash LED controller" depends on OF - depends on GPIOLIB || COMPILE_TEST + depends on GPIOLIB + select LEDS_EXPRESSWIRE help This option enables support for Kinetic KTD2692 LED flash connected through ExpressWire interface. diff --git a/drivers/leds/flash/leds-ktd2692.c b/drivers/leds/flash/leds-ktd2692.c index 598eee5daa52..7bb0aa2753e3 100644 --- a/drivers/leds/flash/leds-ktd2692.c +++ b/drivers/leds/flash/leds-ktd2692.c @@ -6,9 +6,9 @@ * Ingi Kim <ingi2.kim@samsung.com> */ -#include <linux/delay.h> #include <linux/err.h> #include <linux/gpio/consumer.h> +#include <linux/leds-expresswire.h> #include <linux/led-class-flash.h> #include <linux/module.h> #include <linux/mutex.h> @@ -37,22 +37,9 @@ #define KTD2692_REG_FLASH_CURRENT_BASE 0x80 #define KTD2692_REG_MODE_BASE 0xA0 -/* Set bit coding time for expresswire interface */ -#define KTD2692_TIME_RESET_US 700 -#define KTD2692_TIME_DATA_START_TIME_US 10 -#define KTD2692_TIME_HIGH_END_OF_DATA_US 350 -#define KTD2692_TIME_LOW_END_OF_DATA_US 10 -#define KTD2692_TIME_SHORT_BITSET_US 4 -#define KTD2692_TIME_LONG_BITSET_US 12 - /* KTD2692 default length of name */ #define KTD2692_NAME_LENGTH 20 -enum ktd2692_bitset { - KTD2692_LOW = 0, - KTD2692_HIGH, -}; - /* Movie / Flash Mode Control */ enum ktd2692_led_mode { KTD2692_MODE_DISABLE = 0, /* default */ @@ -71,7 +58,19 @@ struct ktd2692_led_config_data { enum led_brightness max_brightness; }; +const struct expresswire_timing ktd2692_timing = { + .poweroff_us = 700, + .data_start_us = 10, + .end_of_data_low_us = 10, + .end_of_data_high_us = 350, + .short_bitset_us = 4, + .long_bitset_us = 12 +}; + struct ktd2692_context { + /* Common ExpressWire properties (ctrl GPIO and timing) */ + struct expresswire_common_props props; + /* Related LED Flash class device */ struct led_classdev_flash fled_cdev; @@ -80,7 +79,6 @@ struct ktd2692_context { struct regulator *regulator; struct gpio_desc *aux_gpio; - struct gpio_desc *ctrl_gpio; enum ktd2692_led_mode mode; enum led_brightness torch_brightness; @@ -92,67 +90,6 @@ static struct ktd2692_context *fled_cdev_to_led( return container_of(fled_cdev, struct ktd2692_context, fled_cdev); } -static void ktd2692_expresswire_start(struct ktd2692_context *led) -{ - gpiod_direction_output(led->ctrl_gpio, KTD2692_HIGH); - udelay(KTD2692_TIME_DATA_START_TIME_US); -} - -static void ktd2692_expresswire_reset(struct ktd2692_context *led) -{ - gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW); - udelay(KTD2692_TIME_RESET_US); -} - -static void ktd2692_expresswire_end(struct ktd2692_context *led) -{ - gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW); - udelay(KTD2692_TIME_LOW_END_OF_DATA_US); - gpiod_direction_output(led->ctrl_gpio, KTD2692_HIGH); - udelay(KTD2692_TIME_HIGH_END_OF_DATA_US); -} - -static void ktd2692_expresswire_set_bit(struct ktd2692_context *led, bool bit) -{ - /* - * The Low Bit(0) and High Bit(1) is based on a time detection - * algorithm between time low and time high - * Time_(L_LB) : Low time of the Low Bit(0) - * Time_(H_LB) : High time of the LOW Bit(0) - * Time_(L_HB) : Low time of the High Bit(1) - * Time_(H_HB) : High time of the High Bit(1) - * - * It can be simplified to: - * Low Bit(0) : 2 * Time_(H_LB) < Time_(L_LB) - * High Bit(1) : 2 * Time_(L_HB) < Time_(H_HB) - * HIGH ___ ____ _.. _________ ___ - * |_________| |_.. |____| |__| - * LOW <L_LB> <H_LB> <L_HB> <H_HB> - * [ Low Bit (0) ] [ High Bit(1) ] - */ - if (bit) { - gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW); - udelay(KTD2692_TIME_SHORT_BITSET_US); - gpiod_direction_output(led->ctrl_gpio, KTD2692_HIGH); - udelay(KTD2692_TIME_LONG_BITSET_US); - } else { - gpiod_direction_output(led->ctrl_gpio, KTD2692_LOW); - udelay(KTD2692_TIME_LONG_BITSET_US); - gpiod_direction_output(led->ctrl_gpio, KTD2692_HIGH); - udelay(KTD2692_TIME_SHORT_BITSET_US); - } -} - -static void ktd2692_expresswire_write(struct ktd2692_context *led, u8 value) -{ - int i; - - ktd2692_expresswire_start(led); - for (i = 7; i >= 0; i--) - ktd2692_expresswire_set_bit(led, value & BIT(i)); - ktd2692_expresswire_end(led); -} - static int ktd2692_led_brightness_set(struct led_classdev *led_cdev, enum led_brightness brightness) { @@ -163,14 +100,14 @@ static int ktd2692_led_brightness_set(struct led_classdev *led_cdev, if (brightness == LED_OFF) { led->mode = KTD2692_MODE_DISABLE; - gpiod_direction_output(led->aux_gpio, KTD2692_LOW); + gpiod_direction_output(led->aux_gpio, 0); } else { - ktd2692_expresswire_write(led, brightness | + expresswire_write_u8(&led->props, brightness | KTD2692_REG_MOVIE_CURRENT_BASE); led->mode = KTD2692_MODE_MOVIE; } - ktd2692_expresswire_write(led, led->mode | KTD2692_REG_MODE_BASE); + expresswire_write_u8(&led->props, led->mode | KTD2692_REG_MODE_BASE); mutex_unlock(&led->lock); return 0; @@ -187,17 +124,17 @@ static int ktd2692_led_flash_strobe_set(struct led_classdev_flash *fled_cdev, if (state) { flash_tm_reg = GET_TIMEOUT_OFFSET(timeout->val, timeout->step); - ktd2692_expresswire_write(led, flash_tm_reg + expresswire_write_u8(&led->props, flash_tm_reg | KTD2692_REG_FLASH_TIMEOUT_BASE); led->mode = KTD2692_MODE_FLASH; - gpiod_direction_output(led->aux_gpio, KTD2692_HIGH); + gpiod_direction_output(led->aux_gpio, 1); } else { led->mode = KTD2692_MODE_DISABLE; - gpiod_direction_output(led->aux_gpio, KTD2692_LOW); + gpiod_direction_output(led->aux_gpio, 0); } - ktd2692_expresswire_write(led, led->mode | KTD2692_REG_MODE_BASE); + expresswire_write_u8(&led->props, led->mode | KTD2692_REG_MODE_BASE); fled_cdev->led_cdev.brightness = LED_OFF; led->mode = KTD2692_MODE_DISABLE; @@ -247,12 +184,12 @@ static void ktd2692_init_flash_timeout(struct led_classdev_flash *fled_cdev, static void ktd2692_setup(struct ktd2692_context *led) { led->mode = KTD2692_MODE_DISABLE; - ktd2692_expresswire_reset(led); - gpiod_direction_output(led->aux_gpio, KTD2692_LOW); + expresswire_power_off(&led->props); + gpiod_direction_output(led->aux_gpio, 0); - ktd2692_expresswire_write(led, (KTD2692_MM_MIN_CURR_THRESHOLD_SCALE - 1) + expresswire_write_u8(&led->props, (KTD2692_MM_MIN_CURR_THRESHOLD_SCALE - 1) | KTD2692_REG_MM_MIN_CURR_THRESHOLD_BASE); - ktd2692_expresswire_write(led, KTD2692_FLASH_MODE_CURR_PERCENT(45) + expresswire_write_u8(&led->props, KTD2692_FLASH_MODE_CURR_PERCENT(45) | KTD2692_REG_FLASH_CURRENT_BASE); } @@ -277,8 +214,8 @@ static int ktd2692_parse_dt(struct ktd2692_context *led, struct device *dev, if (!np) return -ENXIO; - led->ctrl_gpio = devm_gpiod_get(dev, "ctrl", GPIOD_ASIS); - ret = PTR_ERR_OR_ZERO(led->ctrl_gpio); + led->props.ctrl_gpio = devm_gpiod_get(dev, "ctrl", GPIOD_ASIS); + ret = PTR_ERR_OR_ZERO(led->props.ctrl_gpio); if (ret) return dev_err_probe(dev, ret, "cannot get ctrl-gpios\n"); @@ -412,6 +349,7 @@ static struct platform_driver ktd2692_driver = { module_platform_driver(ktd2692_driver); +MODULE_IMPORT_NS(EXPRESSWIRE); MODULE_AUTHOR("Ingi Kim <ingi2.kim@samsung.com>"); MODULE_DESCRIPTION("Kinetic KTD2692 LED driver"); MODULE_LICENSE("GPL v2"); diff --git a/drivers/leds/leds-expresswire.c b/drivers/leds/leds-expresswire.c new file mode 100644 index 000000000000..e4937a8e0f44 --- /dev/null +++ b/drivers/leds/leds-expresswire.c @@ -0,0 +1,72 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Shared library for Kinetic's ExpressWire protocol. + * This protocol works by pulsing the ExpressWire IC's control GPIO. + * ktd2692 and ktd2801 are known to use this protocol. + */ + +#include <linux/bits.h> +#include <linux/delay.h> +#include <linux/export.h> +#include <linux/gpio/consumer.h> +#include <linux/types.h> + +#include <linux/leds-expresswire.h> + +void expresswire_power_off(struct expresswire_common_props *props) +{ + gpiod_set_value_cansleep(props->ctrl_gpio, 0); + usleep_range(props->timing.poweroff_us, props->timing.poweroff_us * 2); +} +EXPORT_SYMBOL_NS_GPL(expresswire_power_off, EXPRESSWIRE); + +void expresswire_enable(struct expresswire_common_props *props) +{ + gpiod_set_value(props->ctrl_gpio, 1); + udelay(props->timing.detect_delay_us); + gpiod_set_value(props->ctrl_gpio, 0); + udelay(props->timing.detect_us); + gpiod_set_value(props->ctrl_gpio, 1); +} +EXPORT_SYMBOL_NS_GPL(expresswire_enable, EXPRESSWIRE); + +void expresswire_start(struct expresswire_common_props *props) +{ + gpiod_set_value(props->ctrl_gpio, 1); + udelay(props->timing.data_start_us); +} +EXPORT_SYMBOL_NS_GPL(expresswire_start, EXPRESSWIRE); + +void expresswire_end(struct expresswire_common_props *props) +{ + gpiod_set_value(props->ctrl_gpio, 0); + udelay(props->timing.end_of_data_low_us); + gpiod_set_value(props->ctrl_gpio, 1); + udelay(props->timing.end_of_data_high_us); +} +EXPORT_SYMBOL_NS_GPL(expresswire_end, EXPRESSWIRE); + +void expresswire_set_bit(struct expresswire_common_props *props, bool bit) +{ + if (bit) { + gpiod_set_value(props->ctrl_gpio, 0); + udelay(props->timing.short_bitset_us); + gpiod_set_value(props->ctrl_gpio, 1); + udelay(props->timing.long_bitset_us); + } else { + gpiod_set_value(props->ctrl_gpio, 0); + udelay(props->timing.long_bitset_us); + gpiod_set_value(props->ctrl_gpio, 1); + udelay(props->timing.short_bitset_us); + } +} +EXPORT_SYMBOL_NS_GPL(expresswire_set_bit, EXPRESSWIRE); + +void expresswire_write_u8(struct expresswire_common_props *props, u8 val) +{ + expresswire_start(props); + for (int i = 7; i >= 0; i--) + expresswire_set_bit(props, val & BIT(i)); + expresswire_end(props); +} +EXPORT_SYMBOL_NS_GPL(expresswire_write_u8, EXPRESSWIRE); diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index ea2d0d69bd8c..230bca07b09d 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -183,6 +183,13 @@ config BACKLIGHT_KTD253 which is a 1-wire GPIO-controlled backlight found in some mobile phones. +config BACKLIGHT_KTD2801 + tristate "Backlight Driver for Kinetic KTD2801" + select LEDS_EXPRESSWIRE + help + Say Y to enable the backlight driver for the Kinetic KTD2801 1-wire + GPIO-controlled backlight found in Samsung Galaxy Core Prime VE LTE. + config BACKLIGHT_KTZ8866 tristate "Backlight Driver for Kinetic KTZ8866" depends on I2C diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index 06966cb20459..8d2cb252042d 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -34,6 +34,7 @@ obj-$(CONFIG_BACKLIGHT_HP680) += hp680_bl.o obj-$(CONFIG_BACKLIGHT_HP700) += jornada720_bl.o obj-$(CONFIG_BACKLIGHT_IPAQ_MICRO) += ipaq_micro_bl.o obj-$(CONFIG_BACKLIGHT_KTD253) += ktd253-backlight.o +obj-$(CONFIG_BACKLIGHT_KTD2801) += ktd2801-backlight.o obj-$(CONFIG_BACKLIGHT_KTZ8866) += ktz8866.o obj-$(CONFIG_BACKLIGHT_LM3533) += lm3533_bl.o obj-$(CONFIG_BACKLIGHT_LM3630A) += lm3630a_bl.o diff --git a/drivers/video/backlight/ktd2801-backlight.c b/drivers/video/backlight/ktd2801-backlight.c new file mode 100644 index 000000000000..d295c2766025 --- /dev/null +++ b/drivers/video/backlight/ktd2801-backlight.c @@ -0,0 +1,128 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Datasheet: + * https://www.kinet-ic.com/uploads/web/KTD2801/KTD2801-04b.pdf + */ +#include <linux/backlight.h> +#include <linux/gpio/consumer.h> +#include <linux/leds-expresswire.h> +#include <linux/platform_device.h> +#include <linux/property.h> + +#define KTD2801_DEFAULT_BRIGHTNESS 100 +#define KTD2801_MAX_BRIGHTNESS 255 + +/* These values have been extracted from Samsung's driver. */ +static const struct expresswire_timing ktd2801_timing = { + .poweroff_us = 2600, + .detect_delay_us = 150, + .detect_us = 270, + .data_start_us = 5, + .short_bitset_us = 5, + .long_bitset_us = 15, + .end_of_data_low_us = 10, + .end_of_data_high_us = 350 +}; + +struct ktd2801_backlight { + struct expresswire_common_props props; + struct backlight_device *bd; + bool was_on; +}; + +static int ktd2801_update_status(struct backlight_device *bd) +{ + struct ktd2801_backlight *ktd2801 = bl_get_data(bd); + u8 brightness = (u8) backlight_get_brightness(bd); + + if (backlight_is_blank(bd)) { + expresswire_power_off(&ktd2801->props); + ktd2801->was_on = false; + return 0; + } + + if (!ktd2801->was_on) { + expresswire_enable(&ktd2801->props); + ktd2801->was_on = true; + } + + expresswire_write_u8(&ktd2801->props, brightness); + + return 0; +} + +static const struct backlight_ops ktd2801_backlight_ops = { + .update_status = ktd2801_update_status, +}; + +static int ktd2801_backlight_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct backlight_device *bd; + struct ktd2801_backlight *ktd2801; + u32 brightness, max_brightness; + int ret; + + ktd2801 = devm_kzalloc(dev, sizeof(*ktd2801), GFP_KERNEL); + if (!ktd2801) + return -ENOMEM; + ktd2801->was_on = true; + ktd2801->props.timing = ktd2801_timing; + + ret = device_property_read_u32(dev, "max-brightness", &max_brightness); + if (ret) + max_brightness = KTD2801_MAX_BRIGHTNESS; + if (max_brightness > KTD2801_MAX_BRIGHTNESS) { + dev_err(dev, "illegal max brightness specified\n"); + max_brightness = KTD2801_MAX_BRIGHTNESS; + } + + ret = device_property_read_u32(dev, "default-brightness", &brightness); + if (ret) + brightness = KTD2801_DEFAULT_BRIGHTNESS; + if (brightness > max_brightness) { + dev_err(dev, "default brightness exceeds max\n"); + brightness = max_brightness; + } + + ktd2801->props.ctrl_gpio = devm_gpiod_get(dev, "ctrl", GPIOD_OUT_HIGH); + if (IS_ERR(ktd2801->props.ctrl_gpio)) + return dev_err_probe(dev, PTR_ERR(ktd2801->props.ctrl_gpio), + "failed to get backlight GPIO"); + gpiod_set_consumer_name(ktd2801->props.ctrl_gpio, dev_name(dev)); + + bd = devm_backlight_device_register(dev, dev_name(dev), dev, ktd2801, + &ktd2801_backlight_ops, NULL); + if (IS_ERR(bd)) + return dev_err_probe(dev, PTR_ERR(bd), + "failed to register backlight"); + + bd->props.max_brightness = max_brightness; + bd->props.brightness = brightness; + + ktd2801->bd = bd; + platform_set_drvdata(pdev, bd); + backlight_update_status(bd); + + return 0; +} + +static const struct of_device_id ktd2801_of_match[] = { + { .compatible = "kinetic,ktd2801" }, + { } +}; +MODULE_DEVICE_TABLE(of, ktd2801_of_match); + +static struct platform_driver ktd2801_backlight_driver = { + .driver = { + .name = "ktd2801-backlight", + .of_match_table = ktd2801_of_match, + }, + .probe = ktd2801_backlight_probe, +}; +module_platform_driver(ktd2801_backlight_driver); + +MODULE_IMPORT_NS(EXPRESSWIRE); +MODULE_AUTHOR("Duje Mihanović <duje.mihanovic@skole.hr>"); +MODULE_DESCRIPTION("Kinetic KTD2801 Backlight Driver"); +MODULE_LICENSE("GPL"); diff --git a/include/linux/leds-expresswire.h b/include/linux/leds-expresswire.h new file mode 100644 index 000000000000..a422921f4159 --- /dev/null +++ b/include/linux/leds-expresswire.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Shared library for Kinetic's ExpressWire protocol. + * This protocol works by pulsing the ExpressWire IC's control GPIO. + * ktd2692 and ktd2801 are known to use this protocol. + */ + +#ifndef _LEDS_EXPRESSWIRE_H +#define _LEDS_EXPRESSWIRE_H + +#include <linux/types.h> + +struct gpio_desc; + +struct expresswire_timing { + unsigned long poweroff_us; + unsigned long detect_delay_us; + unsigned long detect_us; + unsigned long data_start_us; + unsigned long end_of_data_low_us; + unsigned long end_of_data_high_us; + unsigned long short_bitset_us; + unsigned long long_bitset_us; +}; + +struct expresswire_common_props { + struct gpio_desc *ctrl_gpio; + struct expresswire_timing timing; +}; + +void expresswire_power_off(struct expresswire_common_props *props); +void expresswire_enable(struct expresswire_common_props *props); +void expresswire_start(struct expresswire_common_props *props); +void expresswire_end(struct expresswire_common_props *props); +void expresswire_set_bit(struct expresswire_common_props *props, bool bit); +void expresswire_write_u8(struct expresswire_common_props *props, u8 val); + +#endif /* _LEDS_EXPRESSWIRE_H */ |