From 243ce64b2b371cdf2cbc39c9422cb3047cab6de7 Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann Date: Mon, 13 Oct 2025 12:51:57 +0200 Subject: [PATCH 1/7] backlight: Do not include in header file The backlight interfaces don't require anything from , so don't include it. Signed-off-by: Thomas Zimmermann Reviewed-by: Daniel Thompson (RISCstar) Reviewed-by: Simona Vetter Link: https://patch.msgid.link/20251013105553.836715-1-tzimmermann@suse.de Signed-off-by: Lee Jones --- include/linux/backlight.h | 1 - 1 file changed, 1 deletion(-) diff --git a/include/linux/backlight.h b/include/linux/backlight.h index 10e626db7eee..f29a9ef1052e 100644 --- a/include/linux/backlight.h +++ b/include/linux/backlight.h @@ -10,7 +10,6 @@ #define _LINUX_BACKLIGHT_H #include -#include #include #include From d95963e309bc1211e28051314e72638d98225614 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Duje=20Mihanovi=C4=87?= Date: Tue, 29 Jul 2025 19:18:30 +0200 Subject: [PATCH 2/7] backlight: ktd2801: Depend on GPIOLIB MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The LEDS_EXPRESSWIRE library used by the driver requires GPIOLIB. Make sure this dependency is not left unsatisfied. Reported-by: Randy Dunlap Closes: https://lore.kernel.org/all/b6c481bb-e854-405e-a428-90301789fe20@infradead.org/ Signed-off-by: Duje Mihanović Reviewed-by: Daniel Thompson (RISCstar) Reviewed-by: Randy Dunlap Tested-by: Randy Dunlap Acked-by: Randy Dunlap Link: https://patch.msgid.link/20250729-expresswire-dep-fix-v1-2-635cd4cc746b@dujemihanovic.xyz Signed-off-by: Lee Jones --- drivers/video/backlight/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index d9374d208cee..37341474beb9 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -185,6 +185,7 @@ config BACKLIGHT_KTD253 config BACKLIGHT_KTD2801 tristate "Backlight Driver for Kinetic KTD2801" + depends on GPIOLIB || COMPILE_TEST select LEDS_EXPRESSWIRE help Say Y to enable the backlight driver for the Kinetic KTD2801 1-wire From 9341d6698f4cfdfc374fb6944158d111ebe16a9d Mon Sep 17 00:00:00 2001 From: Luca Ceresoli Date: Mon, 19 May 2025 22:19:11 +0200 Subject: [PATCH 3/7] backlight: led-bl: Add devlink to supplier LEDs LED Backlight is a consumer of one or multiple LED class devices, but devlink is currently unable to create correct supplier-producer links when the supplier is a class device. It creates instead a link where the supplier is the parent of the expected device. One consequence is that removal order is not correctly enforced. Issues happen for example with the following sections in a device tree overlay: // An LED driver chip pca9632@62 { compatible = "nxp,pca9632"; reg = <0x62>; // ... addon_led_pwm: led-pwm@3 { reg = <3>; label = "addon:led:pwm"; }; }; backlight-addon { compatible = "led-backlight"; leds = <&addon_led_pwm>; brightness-levels = <255>; default-brightness-level = <255>; }; In this example, the devlink should be created between the backlight-addon (consumer) and the pca9632@62 (supplier). Instead it is created between the backlight-addon (consumer) and the parent of the pca9632@62, which is typically the I2C bus adapter. On removal of the above overlay, the LED driver can be removed before the backlight device, resulting in: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010 ... Call trace: led_put+0xe0/0x140 devm_led_release+0x6c/0x98 Another way to reproduce the bug without any device tree overlays is unbinding the LED class device (pca9632@62) before unbinding the consumer (backlight-addon): echo 11-0062 >/sys/bus/i2c/drivers/leds-pca963x/unbind echo ...backlight-dock >/sys/bus/platform/drivers/led-backlight/unbind Fix by adding a devlink between the consuming led-backlight device and the supplying LED device, as other drivers and subsystems do as well. Fixes: ae232e45acf9 ("backlight: add led-backlight driver") Signed-off-by: Luca Ceresoli Reviewed-by: Daniel Thompson (RISCstar) Reviewed-by: Herve Codina Tested-by: Alexander Sverdlin Link: https://patch.msgid.link/20250519-led-backlight-add-devlink-to-supplier-class-device-v6-1-845224aeb2ce@bootlin.com Signed-off-by: Lee Jones --- drivers/video/backlight/led_bl.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/video/backlight/led_bl.c b/drivers/video/backlight/led_bl.c index efc5e380669a..f7ab9b360731 100644 --- a/drivers/video/backlight/led_bl.c +++ b/drivers/video/backlight/led_bl.c @@ -210,6 +210,19 @@ static int led_bl_probe(struct platform_device *pdev) return PTR_ERR(priv->bl_dev); } + for (i = 0; i < priv->nb_leds; i++) { + struct device_link *link; + + link = device_link_add(&pdev->dev, priv->leds[i]->dev->parent, + DL_FLAG_AUTOREMOVE_CONSUMER); + if (!link) { + dev_err(&pdev->dev, "Failed to add devlink (consumer %s, supplier %s)\n", + dev_name(&pdev->dev), dev_name(priv->leds[i]->dev->parent)); + backlight_device_unregister(priv->bl_dev); + return -EINVAL; + } + } + for (i = 0; i < priv->nb_leds; i++) { mutex_lock(&priv->leds[i]->led_access); led_sysfs_disable(priv->leds[i]); From 147b38a5ad068c43d601addc668937af6b4fe533 Mon Sep 17 00:00:00 2001 From: Junjie Cao Date: Sun, 9 Nov 2025 11:22:40 +0800 Subject: [PATCH 4/7] backlight: aw99706: Add support for Awinic AW99706 backlight Add support for Awinic AW99706 backlight, which can be found in tablet and notebook backlight, one case is the Lenovo Legion Y700 Gen4. This driver refers to the official datasheets and android driver, they can be found in [1]. [1] https://www.awinic.com/en/productDetail/AW99706QNR Signed-off-by: Junjie Cao Tested-by: Pengyu Luo Signed-off-by: Pengyu Luo Reviewed-by: Daniel Thompson (RISCstar) Link: https://patch.msgid.link/20251109032240.3422503-3-caojunjie650@gmail.com Signed-off-by: Lee Jones --- MAINTAINERS | 6 + drivers/video/backlight/Kconfig | 8 + drivers/video/backlight/Makefile | 1 + drivers/video/backlight/aw99706.c | 471 ++++++++++++++++++++++++++++++ 4 files changed, 486 insertions(+) create mode 100644 drivers/video/backlight/aw99706.c diff --git a/MAINTAINERS b/MAINTAINERS index 46126ce2f968..601856d48188 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -4123,6 +4123,12 @@ S: Maintained F: Documentation/devicetree/bindings/iio/adc/avia-hx711.yaml F: drivers/iio/adc/hx711.c +AWINIC AW99706 WLED BACKLIGHT DRIVER +M: Junjie Cao +S: Maintained +F: Documentation/devicetree/bindings/leds/backlight/awinic,aw99706.yaml +F: drivers/video/backlight/aw99706.c + AX.25 NETWORK LAYER L: linux-hams@vger.kernel.org S: Orphan diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig index 37341474beb9..a1422ddd1c22 100644 --- a/drivers/video/backlight/Kconfig +++ b/drivers/video/backlight/Kconfig @@ -156,6 +156,14 @@ config BACKLIGHT_ATMEL_LCDC If in doubt, it's safe to enable this option; it doesn't kick in unless the board's description says it's wired that way. +config BACKLIGHT_AW99706 + tristate "Backlight Driver for Awinic AW99706" + depends on I2C + select REGMAP_I2C + help + If you have a LCD backlight connected to the WLED output of AW99706 + WLED output, say Y here to enable this driver. + config BACKLIGHT_EP93XX tristate "Cirrus EP93xx Backlight Driver" depends on FB_EP93XX diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile index dfbb169bf6ea..a5d62b018102 100644 --- a/drivers/video/backlight/Makefile +++ b/drivers/video/backlight/Makefile @@ -25,6 +25,7 @@ obj-$(CONFIG_BACKLIGHT_ADP8870) += adp8870_bl.o obj-$(CONFIG_BACKLIGHT_APPLE) += apple_bl.o obj-$(CONFIG_BACKLIGHT_APPLE_DWI) += apple_dwi_bl.o obj-$(CONFIG_BACKLIGHT_AS3711) += as3711_bl.o +obj-$(CONFIG_BACKLIGHT_AW99706) += aw99706.o obj-$(CONFIG_BACKLIGHT_BD6107) += bd6107.o obj-$(CONFIG_BACKLIGHT_CLASS_DEVICE) += backlight.o obj-$(CONFIG_BACKLIGHT_DA903X) += da903x_bl.o diff --git a/drivers/video/backlight/aw99706.c b/drivers/video/backlight/aw99706.c new file mode 100644 index 000000000000..b7c1d24b17ac --- /dev/null +++ b/drivers/video/backlight/aw99706.c @@ -0,0 +1,471 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * aw99706 - Backlight driver for the AWINIC AW99706 + * + * Copyright (C) 2025 Junjie Cao + * Copyright (C) 2025 Pengyu Luo + * + * Based on vendor driver: + * Copyright (c) 2023 AWINIC Technology CO., LTD + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +#define AW99706_MAX_BRT_LVL 4095 +#define AW99706_REG_MAX 0x1F +#define AW99706_ID 0x07 + +/* registers list */ +#define AW99706_CFG0_REG 0x00 +#define AW99706_DIM_MODE_MASK GENMASK(1, 0) + +#define AW99706_CFG1_REG 0x01 +#define AW99706_SW_FREQ_MASK GENMASK(3, 0) +#define AW99706_SW_ILMT_MASK GENMASK(5, 4) + +#define AW99706_CFG2_REG 0x02 +#define AW99706_ILED_MAX_MASK GENMASK(6, 0) +#define AW99706_UVLOSEL_MASK BIT(7) + +#define AW99706_CFG3_REG 0x03 +#define AW99706_CFG4_REG 0x04 +#define AW99706_BRT_MSB_MASK GENMASK(3, 0) + +#define AW99706_CFG5_REG 0x05 +#define AW99706_BRT_LSB_MASK GENMASK(7, 0) + +#define AW99706_CFG6_REG 0x06 +#define AW99706_RAMP_CTL_MASK GENMASK(7, 6) + +#define AW99706_CFG7_REG 0x07 +#define AW99706_CFG8_REG 0x08 +#define AW99706_CFG9_REG 0x09 +#define AW99706_CFGA_REG 0x0A +#define AW99706_CFGB_REG 0x0B +#define AW99706_CFGC_REG 0x0C +#define AW99706_CFGD_REG 0x0D +#define AW99706_FLAG_REG 0x10 +#define AW99706_BACKLIGHT_EN_MASK BIT(7) + +#define AW99706_CHIPID_REG 0x11 +#define AW99706_LED_OPEN_FLAG_REG 0x12 +#define AW99706_LED_SHORT_FLAG_REG 0x13 +#define AW99706_MTPLDOSEL_REG 0x1E +#define AW99706_MTPRUN_REG 0x1F + +#define RESV 0 + +/* Boost switching frequency table, in Hz */ +static const u32 aw99706_sw_freq_tbl[] = { + RESV, RESV, RESV, RESV, 300000, 400000, 500000, 600000, + 660000, 750000, 850000, 1000000, 1200000, 1330000, 1500000, 1700000 +}; + +/* Switching current limitation table, in uA */ +static const u32 aw99706_sw_ilmt_tbl[] = { + 1500000, 2000000, 2500000, 3000000 +}; + +/* ULVO threshold table, in uV */ +static const u32 aw99706_ulvo_thres_tbl[] = { + 2200000, 5000000 +}; + +struct aw99706_dt_prop { + const char * const name; + int (*lookup)(const struct aw99706_dt_prop *prop, u32 dt_val, u8 *val); + const u32 * const lookup_tbl; + u8 tbl_size; + u8 reg; + u8 mask; + u32 def_val; +}; + +static int aw99706_dt_property_lookup(const struct aw99706_dt_prop *prop, + u32 dt_val, u8 *val) +{ + int i; + + if (!prop->lookup_tbl) { + *val = dt_val; + return 0; + } + + for (i = 0; i < prop->tbl_size; i++) + if (prop->lookup_tbl[i] == dt_val) + break; + + *val = i; + + return i == prop->tbl_size ? -1 : 0; +} + +#define MIN_ILED_MAX 5000 +#define MAX_ILED_MAX 50000 +#define STEP_ILED_MAX 500 + +static int +aw99706_dt_property_iled_max_convert(const struct aw99706_dt_prop *prop, + u32 dt_val, u8 *val) +{ + if (dt_val > MAX_ILED_MAX || dt_val < MIN_ILED_MAX) + return -1; + + *val = (dt_val - MIN_ILED_MAX) / STEP_ILED_MAX; + + return (dt_val - MIN_ILED_MAX) % STEP_ILED_MAX; +} + +static const struct aw99706_dt_prop aw99706_dt_props[] = { + { + "awinic,dim-mode", aw99706_dt_property_lookup, + NULL, 0, + AW99706_CFG0_REG, AW99706_DIM_MODE_MASK, 1, + }, + { + "awinic,sw-freq", aw99706_dt_property_lookup, + aw99706_sw_freq_tbl, ARRAY_SIZE(aw99706_sw_freq_tbl), + AW99706_CFG1_REG, AW99706_SW_FREQ_MASK, 750000, + }, + { + "awinic,sw-ilmt", aw99706_dt_property_lookup, + aw99706_sw_ilmt_tbl, ARRAY_SIZE(aw99706_sw_ilmt_tbl), + AW99706_CFG1_REG, AW99706_SW_ILMT_MASK, 3000000, + }, + { + "awinic,iled-max", aw99706_dt_property_iled_max_convert, + NULL, 0, + AW99706_CFG2_REG, AW99706_ILED_MAX_MASK, 20000, + + }, + { + "awinic,uvlo-thres", aw99706_dt_property_lookup, + aw99706_ulvo_thres_tbl, ARRAY_SIZE(aw99706_ulvo_thres_tbl), + AW99706_CFG2_REG, AW99706_UVLOSEL_MASK, 2200000, + }, + { + "awinic,ramp-ctl", aw99706_dt_property_lookup, + NULL, 0, + AW99706_CFG6_REG, AW99706_RAMP_CTL_MASK, 2, + } +}; + +struct reg_init_data { + u8 reg; + u8 mask; + u8 val; +}; + +struct aw99706_device { + struct i2c_client *client; + struct device *dev; + struct regmap *regmap; + struct backlight_device *bl_dev; + struct gpio_desc *hwen_gpio; + struct reg_init_data init_tbl[ARRAY_SIZE(aw99706_dt_props)]; + bool bl_enable; +}; + +enum reg_access { + REG_NONE_ACCESS = 0, + REG_RD_ACCESS = 1, + REG_WR_ACCESS = 2, +}; + +static const u8 aw99706_regs[AW99706_REG_MAX + 1] = { + [AW99706_CFG0_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFG1_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFG2_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFG3_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFG4_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFG5_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFG6_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFG7_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFG8_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFG9_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFGA_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFGB_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFGC_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_CFGD_REG] = REG_RD_ACCESS | REG_WR_ACCESS, + [AW99706_FLAG_REG] = REG_RD_ACCESS, + [AW99706_CHIPID_REG] = REG_RD_ACCESS, + [AW99706_LED_OPEN_FLAG_REG] = REG_RD_ACCESS, + [AW99706_LED_SHORT_FLAG_REG] = REG_RD_ACCESS, + + /* + * Write bit is dropped here, writing BIT(0) to MTPLDOSEL will unlock + * Multi-time Programmable (MTP). + */ + [AW99706_MTPLDOSEL_REG] = REG_RD_ACCESS, + [AW99706_MTPRUN_REG] = REG_NONE_ACCESS, +}; + +static bool aw99706_readable_reg(struct device *dev, unsigned int reg) +{ + return aw99706_regs[reg] & REG_RD_ACCESS; +} + +static bool aw99706_writeable_reg(struct device *dev, unsigned int reg) +{ + return aw99706_regs[reg] & REG_WR_ACCESS; +} + +static inline int aw99706_i2c_read(struct aw99706_device *aw, u8 reg, + unsigned int *val) +{ + return regmap_read(aw->regmap, reg, val); +} + +static inline int aw99706_i2c_write(struct aw99706_device *aw, u8 reg, u8 val) +{ + return regmap_write(aw->regmap, reg, val); +} + +static inline int aw99706_i2c_update_bits(struct aw99706_device *aw, u8 reg, + u8 mask, u8 val) +{ + return regmap_update_bits(aw->regmap, reg, mask, val); +} + +static void aw99706_dt_parse(struct aw99706_device *aw, + struct backlight_properties *bl_props) +{ + const struct aw99706_dt_prop *prop; + u32 dt_val; + int ret, i; + u8 val; + + for (i = 0; i < ARRAY_SIZE(aw99706_dt_props); i++) { + prop = &aw99706_dt_props[i]; + ret = device_property_read_u32(aw->dev, prop->name, &dt_val); + if (ret < 0) + dt_val = prop->def_val; + + if (prop->lookup(prop, dt_val, &val)) { + dev_warn(aw->dev, "invalid value %d for property %s, using default value %d\n", + dt_val, prop->name, prop->def_val); + + prop->lookup(prop, prop->def_val, &val); + } + + aw->init_tbl[i].reg = prop->reg; + aw->init_tbl[i].mask = prop->mask; + aw->init_tbl[i].val = val << __ffs(prop->mask); + } + + bl_props->brightness = AW99706_MAX_BRT_LVL >> 1; + bl_props->max_brightness = AW99706_MAX_BRT_LVL; + device_property_read_u32(aw->dev, "default-brightness", + &bl_props->brightness); + device_property_read_u32(aw->dev, "max-brightness", + &bl_props->max_brightness); + + if (bl_props->max_brightness > AW99706_MAX_BRT_LVL) + bl_props->max_brightness = AW99706_MAX_BRT_LVL; + + if (bl_props->brightness > bl_props->max_brightness) + bl_props->brightness = bl_props->max_brightness; +} + +static int aw99706_hw_init(struct aw99706_device *aw) +{ + int ret, i; + + gpiod_set_value_cansleep(aw->hwen_gpio, 1); + + for (i = 0; i < ARRAY_SIZE(aw->init_tbl); i++) { + ret = aw99706_i2c_update_bits(aw, aw->init_tbl[i].reg, + aw->init_tbl[i].mask, + aw->init_tbl[i].val); + if (ret < 0) { + dev_err(aw->dev, "Failed to write init data %d\n", ret); + return ret; + } + } + + return 0; +} + +static int aw99706_bl_enable(struct aw99706_device *aw, bool en) +{ + int ret; + u8 val; + + val = FIELD_PREP(AW99706_BACKLIGHT_EN_MASK, en); + ret = aw99706_i2c_update_bits(aw, AW99706_CFGD_REG, + AW99706_BACKLIGHT_EN_MASK, val); + if (ret) + dev_err(aw->dev, "Failed to enable backlight!\n"); + + return ret; +} + +static int aw99706_update_brightness(struct aw99706_device *aw, u32 brt_lvl) +{ + bool bl_enable_now = !!brt_lvl; + int ret; + + ret = aw99706_i2c_write(aw, AW99706_CFG4_REG, + (brt_lvl >> 8) & AW99706_BRT_MSB_MASK); + if (ret < 0) + return ret; + + ret = aw99706_i2c_write(aw, AW99706_CFG5_REG, + brt_lvl & AW99706_BRT_LSB_MASK); + if (ret < 0) + return ret; + + if (aw->bl_enable != bl_enable_now) { + ret = aw99706_bl_enable(aw, bl_enable_now); + if (!ret) + aw->bl_enable = bl_enable_now; + } + + return ret; +} + +static int aw99706_bl_update_status(struct backlight_device *bl) +{ + struct aw99706_device *aw = bl_get_data(bl); + + return aw99706_update_brightness(aw, bl->props.brightness); +} + +static const struct backlight_ops aw99706_bl_ops = { + .options = BL_CORE_SUSPENDRESUME, + .update_status = aw99706_bl_update_status, +}; + +static const struct regmap_config aw99706_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = AW99706_REG_MAX, + .writeable_reg = aw99706_writeable_reg, + .readable_reg = aw99706_readable_reg, +}; + +static int aw99706_chip_id_read(struct aw99706_device *aw) +{ + int ret; + unsigned int val; + + ret = aw99706_i2c_read(aw, AW99706_CHIPID_REG, &val); + if (ret < 0) + return ret; + + return val; +} + +static int aw99706_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct aw99706_device *aw; + struct backlight_device *bl_dev; + struct backlight_properties props = {}; + int ret = 0; + + aw = devm_kzalloc(dev, sizeof(*aw), GFP_KERNEL); + if (!aw) + return -ENOMEM; + + aw->client = client; + aw->dev = dev; + i2c_set_clientdata(client, aw); + + aw->regmap = devm_regmap_init_i2c(client, &aw99706_regmap_config); + if (IS_ERR(aw->regmap)) + return dev_err_probe(dev, PTR_ERR(aw->regmap), + "Failed to init regmap\n"); + + ret = aw99706_chip_id_read(aw); + if (ret != AW99706_ID) + return dev_err_probe(dev, -ENODEV, + "Unknown chip id 0x%02x\n", ret); + + aw99706_dt_parse(aw, &props); + + aw->hwen_gpio = devm_gpiod_get(aw->dev, "enable", GPIOD_OUT_LOW); + if (IS_ERR(aw->hwen_gpio)) + return dev_err_probe(dev, PTR_ERR(aw->hwen_gpio), + "Failed to get enable gpio\n"); + + ret = aw99706_hw_init(aw); + if (ret < 0) + return dev_err_probe(dev, ret, + "Failed to initialize the chip\n"); + + props.type = BACKLIGHT_RAW; + props.scale = BACKLIGHT_SCALE_LINEAR; + + bl_dev = devm_backlight_device_register(dev, "aw99706-backlight", dev, + aw, &aw99706_bl_ops, &props); + if (IS_ERR(bl_dev)) + return dev_err_probe(dev, PTR_ERR(bl_dev), + "Failed to register backlight!\n"); + + aw->bl_dev = bl_dev; + + return 0; +} + +static void aw99706_remove(struct i2c_client *client) +{ + struct aw99706_device *aw = i2c_get_clientdata(client); + + aw99706_update_brightness(aw, 0); + + msleep(50); + + gpiod_set_value_cansleep(aw->hwen_gpio, 0); +} + +static int aw99706_suspend(struct device *dev) +{ + struct aw99706_device *aw = dev_get_drvdata(dev); + + return aw99706_update_brightness(aw, 0); +} + +static int aw99706_resume(struct device *dev) +{ + struct aw99706_device *aw = dev_get_drvdata(dev); + + return aw99706_hw_init(aw); +} + +static SIMPLE_DEV_PM_OPS(aw99706_pm_ops, aw99706_suspend, aw99706_resume); + +static const struct i2c_device_id aw99706_ids[] = { + { "aw99706" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, aw99706_ids); + +static const struct of_device_id aw99706_match_table[] = { + { .compatible = "awinic,aw99706", }, + { } +}; +MODULE_DEVICE_TABLE(of, aw99706_match_table); + +static struct i2c_driver aw99706_i2c_driver = { + .probe = aw99706_probe, + .remove = aw99706_remove, + .id_table = aw99706_ids, + .driver = { + .name = "aw99706", + .of_match_table = aw99706_match_table, + .pm = &aw99706_pm_ops, + }, +}; + +module_i2c_driver(aw99706_i2c_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("BackLight driver for aw99706"); From 25c2b404cd3fe00f3a1c61b6dffd6c98a0a70170 Mon Sep 17 00:00:00 2001 From: Junjie Cao Date: Sun, 9 Nov 2025 11:22:39 +0800 Subject: [PATCH 5/7] dt-bindings: leds: backlight: Add Awinic AW99706 backlight Add Awinic AW99706 backlight binding documentation. Signed-off-by: Junjie Cao Reviewed-by: Daniel Thompson (RISCstar) Reviewed-by: Krzysztof Kozlowski Link: https://patch.msgid.link/20251109032240.3422503-2-caojunjie650@gmail.com Signed-off-by: Lee Jones --- .../leds/backlight/awinic,aw99706.yaml | 101 ++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 Documentation/devicetree/bindings/leds/backlight/awinic,aw99706.yaml diff --git a/Documentation/devicetree/bindings/leds/backlight/awinic,aw99706.yaml b/Documentation/devicetree/bindings/leds/backlight/awinic,aw99706.yaml new file mode 100644 index 000000000000..f48ce7a3434d --- /dev/null +++ b/Documentation/devicetree/bindings/leds/backlight/awinic,aw99706.yaml @@ -0,0 +1,101 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/leds/backlight/awinic,aw99706.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Awinic AW99706 6-channel WLED Backlight Driver + +maintainers: + - Junjie Cao + +allOf: + - $ref: common.yaml# + +properties: + compatible: + const: awinic,aw99706 + + reg: + maxItems: 1 + + enable-gpios: + description: GPIO to use to enable/disable the backlight (HWEN pin). + maxItems: 1 + + awinic,dim-mode: + $ref: /schemas/types.yaml#/definitions/uint32 + description: > + Select dimming mode of the device. + 0 = Bypass mode. + 1 = DC mode. + 2 = MIX mode(PWM at low brightness and DC at high brightness). + 3 = MIX-26k mode(MIX mode with different PWM frequency). + enum: [ 0, 1, 2, 3 ] + default: 1 + + awinic,sw-freq-hz: + description: Boost switching frequency in Hz. + enum: [ 300000, 400000, 500000, 600000, 660000, 750000, 850000, 1000000, + 1200000, 1330000, 1500000, 1700000 ] + default: 750000 + + awinic,sw-ilmt-microamp: + description: Switching current limitation in uA. + enum: [ 1500000, 2000000, 2500000, 3000000 ] + default: 3000000 + + awinic,iled-max-microamp: + description: Maximum LED current setting in uA. + minimum: 5000 + maximum: 50000 + multipleOf: 500 + default: 20000 + + awinic,uvlo-thres-microvolt: + description: UVLO(Under Voltage Lock Out) in uV. + enum: [ 2200000, 5000000 ] + default: 2200000 + + awinic,ramp-ctl: + $ref: /schemas/types.yaml#/definitions/uint32 + description: > + Select ramp control and filter of the device. + 0 = Fade in/fade out. + 1 = Light filter. + 2 = Medium filter. + 3 = Heavy filter. + enum: [ 0, 1, 2, 3 ] + default: 2 + +required: + - compatible + - reg + - enable-gpios + +unevaluatedProperties: false + +examples: + - | + #include + + i2c { + #address-cells = <1>; + #size-cells = <0>; + + backlight@76 { + compatible = "awinic,aw99706"; + reg = <0x76>; + enable-gpios = <&tlmm 88 GPIO_ACTIVE_HIGH>; + default-brightness = <2047>; + max-brightness = <4095>; + awinic,dim-mode = <1>; + awinic,sw-freq-hz = <750000>; + awinic,sw-ilmt-microamp = <3000000>; + awinic,uvlo-thres-microvolt = <2200000>; + awinic,iled-max-microamp = <20000>; + awinic,ramp-ctl = <2>; + }; + }; + +... From 2d45db63260c6ae3cf007361e04a1c41bd265084 Mon Sep 17 00:00:00 2001 From: Randy Dunlap Date: Mon, 10 Nov 2025 22:09:16 -0800 Subject: [PATCH 6/7] backlight: lp855x: Fix lp855x.h kernel-doc warnings Add a missing struct short description and a missing leading " *" to lp855x.h to avoid kernel-doc warnings: Warning: include/linux/platform_data/lp855x.h:126 missing initial short description on line: * struct lp855x_platform_data Warning: include/linux/platform_data/lp855x.h:131 bad line: Only valid when mode is PWM_BASED. Fixes: 7be865ab8634 ("backlight: new backlight driver for LP855x devices") Signed-off-by: Randy Dunlap Reviewed-by: Daniel Thompson (RISCstar) Link: https://patch.msgid.link/20251111060916.1995920-1-rdunlap@infradead.org Signed-off-by: Lee Jones --- include/linux/platform_data/lp855x.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/platform_data/lp855x.h b/include/linux/platform_data/lp855x.h index ab222dd05bbc..3b4a891acefe 100644 --- a/include/linux/platform_data/lp855x.h +++ b/include/linux/platform_data/lp855x.h @@ -124,12 +124,12 @@ struct lp855x_rom_data { }; /** - * struct lp855x_platform_data + * struct lp855x_platform_data - lp855 platform-specific data * @name : Backlight driver name. If it is not defined, default name is set. * @device_control : value of DEVICE CONTROL register * @initial_brightness : initial value of backlight brightness * @period_ns : platform specific pwm period value. unit is nano. - Only valid when mode is PWM_BASED. + * Only valid when mode is PWM_BASED. * @size_program : total size of lp855x_rom_data * @rom_data : list of new eeprom/eprom registers */ From d3cc7cd7bc46af587747399e956cf4508221476f Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Thu, 20 Nov 2025 13:22:46 -0700 Subject: [PATCH 7/7] backlight: aw99706: Fix unused function warnings from suspend/resume ops When building for a platform without CONFIG_PM_SLEEP, such as s390, there are two unused function warnings: drivers/video/backlight/aw99706.c:436:12: error: 'aw99706_resume' defined but not used [-Werror=unused-function] 436 | static int aw99706_resume(struct device *dev) | ^~~~~~~~~~~~~~ drivers/video/backlight/aw99706.c:429:12: error: 'aw99706_suspend' defined but not used [-Werror=unused-function] 429 | static int aw99706_suspend(struct device *dev) | ^~~~~~~~~~~~~~~ SET_SYSTEM_SLEEP_PM_OPS, used within SIMPLE_DEV_PM_OPS, expands to nothing when CONFIG_PM_SLEEP is not set, so these functions are completely unused in this configuration. SIMPLE_DEV_PM_OPS is deprecated in favor of DEFINE_SIMPLE_DEV_PM_OPS, which avoids this issue by using pm_sleep_ptr to make these callbacks NULL when CONFIG_PM_SLEEP is unset while making the callback functions always appear used to the compiler regardless of configuration. Switch to DEFINE_SIMPLE_DEV_PM_OPS for aw99706_pm_ops to clear up the warning. Additionally, wrap the pointer to aw99706_pm_ops in pm_ptr() in aw99706_i2c_driver to ensure that the structure is completely eliminated in configurations without CONFIG_PM. Fixes: 88a8e9b49ee8 ("backlight: aw99706: Add support for Awinic AW99706 backlight") Signed-off-by: Nathan Chancellor Link: https://patch.msgid.link/20251120-backlight-aw99706-fix-unused-pm-functions-v1-1-8b9c17c4e783@kernel.org Signed-off-by: Lee Jones --- drivers/video/backlight/aw99706.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/video/backlight/aw99706.c b/drivers/video/backlight/aw99706.c index b7c1d24b17ac..df5b23b2f753 100644 --- a/drivers/video/backlight/aw99706.c +++ b/drivers/video/backlight/aw99706.c @@ -440,7 +440,7 @@ static int aw99706_resume(struct device *dev) return aw99706_hw_init(aw); } -static SIMPLE_DEV_PM_OPS(aw99706_pm_ops, aw99706_suspend, aw99706_resume); +static DEFINE_SIMPLE_DEV_PM_OPS(aw99706_pm_ops, aw99706_suspend, aw99706_resume); static const struct i2c_device_id aw99706_ids[] = { { "aw99706" }, @@ -461,7 +461,7 @@ static struct i2c_driver aw99706_i2c_driver = { .driver = { .name = "aw99706", .of_match_table = aw99706_match_table, - .pm = &aw99706_pm_ops, + .pm = pm_ptr(&aw99706_pm_ops), }, };