From 1368d06dd2c99186174290c03d79c132db16efe2 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Duje=20Mihanovi=C4=87?= Date: Thu, 25 Jan 2024 16:30:53 +0100 Subject: [PATCH 1/7] leds: Introduce ExpressWire library MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The ExpressWire protocol is shared between at least KTD2692 and KTD2801 with slight differences such as timings and the former not having a defined set of pulses for enabling the protocol (possibly because it does not support PWM unlike KTD2801). Despite these differences the ExpressWire handling code can be shared between the two, so in preparation for adding KTD2801 support introduce a library implementing this protocol. Suggested-by: Daniel Thompson Reviewed-by: Linus Walleij Reviewed-by: Daniel Thompson Signed-off-by: Duje Mihanović Link: https://lore.kernel.org/r/20240125-ktd2801-v5-1-e22da232a825@skole.hr Signed-off-by: Lee Jones --- MAINTAINERS | 7 ++++ drivers/leds/Kconfig | 4 ++ drivers/leds/Makefile | 3 ++ drivers/leds/leds-expresswire.c | 68 ++++++++++++++++++++++++++++++++ include/linux/leds-expresswire.h | 36 +++++++++++++++++ 5 files changed, 118 insertions(+) create mode 100644 drivers/leds/leds-expresswire.c create mode 100644 include/linux/leds-expresswire.h diff --git a/MAINTAINERS b/MAINTAINERS index 8d1052fa6a69..e1c83e0e837a 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 +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 L: linux-ext4@vger.kernel.org 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/leds-expresswire.c b/drivers/leds/leds-expresswire.c new file mode 100644 index 000000000000..89e147b0e019 --- /dev/null +++ b/drivers/leds/leds-expresswire.c @@ -0,0 +1,68 @@ +// 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 +#include +#include + +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/include/linux/leds-expresswire.h b/include/linux/leds-expresswire.h new file mode 100644 index 000000000000..3c61902ccac8 --- /dev/null +++ b/include/linux/leds-expresswire.h @@ -0,0 +1,36 @@ +/* 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 + +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 */ From b5a8c50e5c1896b913c289e09f98b539fd1740ac Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Duje=20Mihanovi=C4=87?= Date: Thu, 25 Jan 2024 16:30:54 +0100 Subject: [PATCH 2/7] leds: ktd2692: Convert to use ExpressWire library MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The KTD2692 uses the ExpressWire protocol implemented in the newly introduced ExpressWire library. Convert the driver to use the library. Suggested-by: Daniel Thompson Reviewed-by: Linus Walleij Reviewed-by: Daniel Thompson Signed-off-by: Duje Mihanović Link: https://lore.kernel.org/r/20240125-ktd2801-v5-2-e22da232a825@skole.hr Signed-off-by: Lee Jones --- drivers/leds/flash/Kconfig | 2 +- drivers/leds/flash/leds-ktd2692.c | 116 +++++++----------------------- 2 files changed, 28 insertions(+), 90 deletions(-) diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig index 4e08dbc05709..a0fb755b58dc 100644 --- a/drivers/leds/flash/Kconfig +++ b/drivers/leds/flash/Kconfig @@ -23,7 +23,7 @@ config LEDS_AS3645A config LEDS_KTD2692 tristate "LED support for Kinetic KTD2692 flash LED controller" depends on OF - depends on GPIOLIB || COMPILE_TEST + 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 */ -#include #include #include +#include #include #include #include @@ -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 - * [ 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 "); MODULE_DESCRIPTION("Kinetic KTD2692 LED driver"); MODULE_LICENSE("GPL v2"); From 922235a9b89417e4c355ca813a1049c755b89570 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Duje=20Mihanovi=C4=87?= Date: Thu, 25 Jan 2024 16:30:55 +0100 Subject: [PATCH 3/7] dt-bindings: backlight: Add Kinetic KTD2801 binding MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit KTD2801 is a LED backlight driver IC found in samsung,coreprimevelte. The brightness can be set using PWM or the ExpressWire protocol. Add a DT binding for the KTD2801. Reviewed-by: Krzysztof Kozlowski Reviewed-by: Linus Walleij Reviewed-by: Daniel Thompson Signed-off-by: Duje Mihanović Link: https://lore.kernel.org/r/20240125-ktd2801-v5-3-e22da232a825@skole.hr Signed-off-by: Lee Jones --- .../leds/backlight/kinetic,ktd2801.yaml | 46 +++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/backlight/kinetic,ktd2801.yaml 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 + +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 + + backlight { + compatible = "kinetic,ktd2801"; + ctrl-gpios = <&gpio 97 GPIO_ACTIVE_HIGH>; + max-brightness = <210>; + default-brightness = <100>; + }; From a5554f1b5bc3be5d01f41b7550aa5b05b7c88c09 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Duje=20Mihanovi=C4=87?= Date: Thu, 25 Jan 2024 16:30:56 +0100 Subject: [PATCH 4/7] backlight: Add Kinetic KTD2801 Backlight support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit KTD2801 is a LED backlight driver IC found in samsung,coreprimevelte. The brightness can be set using PWM or the ExpressWire protocol. Add support for the KTD2801. Reviewed-by: Linus Walleij Reviewed-by: Daniel Thompson Signed-off-by: Duje Mihanović Link: https://lore.kernel.org/r/20240125-ktd2801-v5-4-e22da232a825@skole.hr Signed-off-by: Lee Jones --- MAINTAINERS | 6 + drivers/video/backlight/Kconfig | 7 ++ drivers/video/backlight/Makefile | 1 + drivers/video/backlight/ktd2801-backlight.c | 128 ++++++++++++++++++++ 4 files changed, 142 insertions(+) create mode 100644 drivers/video/backlight/ktd2801-backlight.c diff --git a/MAINTAINERS b/MAINTAINERS index e1c83e0e837a..01cd1a460907 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -12052,6 +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 +S: Maintained +F: Documentation/devicetree/bindings/leds/backlight/kinetic,ktd2801.yaml +F: drivers/video/backlight/ktd2801-backlight.c + KTEST M: Steven Rostedt M: John Hawley 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..c020acff40f1 --- /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 +#include +#include +#include +#include + +#define KTD2801_DEFAULT_BRIGHTNESS 100 +#define KTD2801_MAX_BRIGHTNESS 255 + +/* These values have been extracted from Samsung's driver. */ +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 "); +MODULE_DESCRIPTION("Kinetic KTD2801 Backlight Driver"); +MODULE_LICENSE("GPL"); From 7534904d421e92d0b1ab46c29f899f7c96697f4c Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Duje=20Mihanovi=C4=87?= Date: Sat, 10 Feb 2024 17:16:17 +0100 Subject: [PATCH 5/7] backlight: ktd2801: Make timing struct static MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The struct containing the KTD2801 timing can be made static as it's not referenced outside the KTD2801 driver. Do this to prevent sparse complaints. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202402100625.M0RkJhMh-lkp@intel.com/ Signed-off-by: Duje Mihanović Reviewed-by: Daniel Thompson Link: https://lore.kernel.org/r/20240210-ktd2801-static-v1-1-90ad2e2e8483@skole.hr Signed-off-by: Lee Jones --- drivers/video/backlight/ktd2801-backlight.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/video/backlight/ktd2801-backlight.c b/drivers/video/backlight/ktd2801-backlight.c index c020acff40f1..d295c2766025 100644 --- a/drivers/video/backlight/ktd2801-backlight.c +++ b/drivers/video/backlight/ktd2801-backlight.c @@ -13,7 +13,7 @@ #define KTD2801_MAX_BRIGHTNESS 255 /* These values have been extracted from Samsung's driver. */ -const struct expresswire_timing ktd2801_timing = { +static const struct expresswire_timing ktd2801_timing = { .poweroff_us = 2600, .detect_delay_us = 150, .detect_us = 270, From d48ece99f2d90be333dad38cba0dc6fadc7dff8c Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 13 Feb 2024 17:55:50 +0100 Subject: [PATCH 6/7] leds: ktd2692: Add GPIOLIB dependency The expresswire module requires gpiolib, so anything selecting it also needs this dependency: WARNING: unmet direct dependencies detected for LEDS_EXPRESSWIRE Depends on [n]: NEW_LEDS [=y] && GPIOLIB [=n] Selected by [y]: - LEDS_KTD2692 [=y] && NEW_LEDS [=y] && LEDS_CLASS_FLASH [=y] && OF [=y] Fixes: e59a15af7aa6 ("leds: ktd2692: Convert to use ExpressWire library") Signed-off-by: Arnd Bergmann Reviewed-by: Daniel Thompson Link: https://lore.kernel.org/r/20240213165602.2230970-1-arnd@kernel.org Signed-off-by: Lee Jones --- drivers/leds/flash/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/leds/flash/Kconfig b/drivers/leds/flash/Kconfig index a0fb755b58dc..24722d581369 100644 --- a/drivers/leds/flash/Kconfig +++ b/drivers/leds/flash/Kconfig @@ -23,6 +23,7 @@ config LEDS_AS3645A config LEDS_KTD2692 tristate "LED support for Kinetic KTD2692 flash LED controller" depends on OF + depends on GPIOLIB select LEDS_EXPRESSWIRE help This option enables support for Kinetic KTD2692 LED flash connected From 7774f3d1dd3822e938e236df67766436c0debd11 Mon Sep 17 00:00:00 2001 From: Andy Shevchenko Date: Fri, 23 Feb 2024 22:30:00 +0200 Subject: [PATCH 7/7] leds: expresswire: Don't use "proxy" headers MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Update header inclusions to follow IWYU (Include What You Use) principle. Signed-off-by: Andy Shevchenko Reviewed-by: Duje Mihanović Link: https://lore.kernel.org/r/20240223203010.881065-1-andriy.shevchenko@linux.intel.com Signed-off-by: Lee Jones --- drivers/leds/leds-expresswire.c | 4 ++++ include/linux/leds-expresswire.h | 4 +++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/leds/leds-expresswire.c b/drivers/leds/leds-expresswire.c index 89e147b0e019..e4937a8e0f44 100644 --- a/drivers/leds/leds-expresswire.c +++ b/drivers/leds/leds-expresswire.c @@ -5,8 +5,12 @@ * ktd2692 and ktd2801 are known to use this protocol. */ +#include #include +#include #include +#include + #include void expresswire_power_off(struct expresswire_common_props *props) diff --git a/include/linux/leds-expresswire.h b/include/linux/leds-expresswire.h index 3c61902ccac8..a422921f4159 100644 --- a/include/linux/leds-expresswire.h +++ b/include/linux/leds-expresswire.h @@ -8,7 +8,9 @@ #ifndef _LEDS_EXPRESSWIRE_H #define _LEDS_EXPRESSWIRE_H -#include +#include + +struct gpio_desc; struct expresswire_timing { unsigned long poweroff_us;