Merge tag 'backlight-next-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight

Pull backlight updates from Lee Jones:
 "New Functionality:
   - Add support for an enable GPIO; lm3630a_bl
   - Add support for short circuit handling; qcom-wled
   - Add support for automatic string detection; qcom-wled

  Fix-ups:
   - Update Device Tree bindings; lm3630a-backlight, led-backlight,
     qcom-wled
   - Constify; ipaq_micro_bl
   - Optimise for CPU cycles; pwm_bl
   - Coding style fix-ups; pwm_bl
   - Trivial fix-ups (white space, comments, renaming); pwm_bl,
     gpio_backlight, qcom-wled
   - Kconfig dependency hacking; LCD_HP700
   - Rename, refactor and add peripherals; pm8941-wled => qcom-wled
   - Make use of GPIO look-up tables; tosa_bl, tosa_lcd
   - Remove superfluous code; gpio_backlight
   - Adapt GPIO direction handling; gpio_backlight
   - Remove legacy use of platform data; gpio_backlight

  Bug Fixes:
   - Provide modules aliases; lm3630a_bl"

* tag 'backlight-next-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight: (32 commits)
  backlight: qcom-wled: Fix spelling mistake "trigged" -> "triggered"
  backlight: gpio: Pull gpio_backlight_initial_power_state() into probe
  backlight: gpio: Use a helper variable for &pdev->dev
  backlight: gpio: Remove unused fields from platform data
  sh: ecovec24: don't set unused fields in platform data
  backlight: gpio: Simplify the platform data handling
  sh: ecovec24: add additional properties to the backlight device
  backlight: gpio: Explicitly set the direction of the GPIO
  backlight: gpio: Remove stray newline
  backlight: gpio: Remove unneeded include
  video: backlight: tosa: Use GPIO lookup table
  backlight: qcom-wled: Add auto string detection logic
  backlight: qcom-wled: Add support for short circuit handling
  backlight: qcom-wled: Add support for WLED4 peripheral
  backlight: qcom-wled: Restructure the driver for WLED3
  backlight: qcom-wled: Rename PM8941* to WLED3
  backlight: qcom-wled: Add new properties for PMI8998
  backlight: qcom-wled: Restructure the qcom-wled bindings
  backlight: qcom-wled: Rename pm8941-wled.c to qcom-wled.c
  dt-bindings: backlight: lm3630a: Fix missing include
  ...

11 files changed, 1418 insertions, 544 deletions

diff --git a/drivers/video/backlight/Kconfig b/drivers/video/backlight/Kconfig
index 40676be2e46a..403707a3e503 100644
--- a/drivers/video/backlight/Kconfig
+++ b/drivers/video/backlight/Kconfig
@@ -99,7 +99,7 @@ config LCD_TOSA
 
 config LCD_HP700
 	tristate "HP Jornada 700 series LCD Driver"
-	depends on SA1100_JORNADA720_SSP && !PREEMPT
+	depends on SA1100_JORNADA720_SSP && !PREEMPTION
 	default y
 	help
 	  If you have an HP Jornada 700 series handheld (710/720/728)
@@ -228,7 +228,7 @@ config BACKLIGHT_HP680
 
 config BACKLIGHT_HP700
 	tristate "HP Jornada 700 series Backlight Driver"
-	depends on SA1100_JORNADA720_SSP && !PREEMPT
+	depends on SA1100_JORNADA720_SSP && !PREEMPTION
 	default y
 	help
 	  If you have an HP Jornada 700 series,
@@ -282,12 +282,12 @@ config BACKLIGHT_TOSA
 	  If you have an Sharp SL-6000 Zaurus say Y to enable a driver
 	  for its backlight
 
-config BACKLIGHT_PM8941_WLED
-	tristate "Qualcomm PM8941 WLED Driver"
+config BACKLIGHT_QCOM_WLED
+	tristate "Qualcomm PMIC WLED Driver"
 	select REGMAP
 	help
-	  If you have the Qualcomm PM8941, say Y to enable a driver for the
-	  WLED block.
+	  If you have the Qualcomm PMIC, say Y to enable a driver for the
+	  WLED block. Currently it supports PM8941 and PMI8998.
 
 config BACKLIGHT_SAHARA
 	tristate "Tabletkiosk Sahara Touch-iT Backlight Driver"
diff --git a/drivers/video/backlight/Makefile b/drivers/video/backlight/Makefile
index 63c507c07437..6f8777037c37 100644
--- a/drivers/video/backlight/Makefile
+++ b/drivers/video/backlight/Makefile
@@ -48,8 +48,8 @@ obj-$(CONFIG_BACKLIGHT_OMAP1)		+= omap1_bl.o
 obj-$(CONFIG_BACKLIGHT_OT200)		+= ot200_bl.o
 obj-$(CONFIG_BACKLIGHT_PANDORA)		+= pandora_bl.o
 obj-$(CONFIG_BACKLIGHT_PCF50633)	+= pcf50633-backlight.o
-obj-$(CONFIG_BACKLIGHT_PM8941_WLED)	+= pm8941-wled.o
 obj-$(CONFIG_BACKLIGHT_PWM)		+= pwm_bl.o
+obj-$(CONFIG_BACKLIGHT_QCOM_WLED)	+= qcom-wled.o
 obj-$(CONFIG_BACKLIGHT_SAHARA)		+= kb3886_bl.o
 obj-$(CONFIG_BACKLIGHT_SKY81452)	+= sky81452-backlight.o
 obj-$(CONFIG_BACKLIGHT_TOSA)		+= tosa_bl.o
diff --git a/drivers/video/backlight/gpio_backlight.c b/drivers/video/backlight/gpio_backlight.c
index 18e053e4716c..75409ddfba3e 100644
--- a/drivers/video/backlight/gpio_backlight.c
+++ b/drivers/video/backlight/gpio_backlight.c
@@ -6,29 +6,23 @@
 #include <linux/backlight.h>
 #include <linux/err.h>
 #include <linux/fb.h>
-#include <linux/gpio.h> /* Only for legacy support */
 #include <linux/gpio/consumer.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/of.h>
-#include <linux/of_gpio.h>
 #include <linux/platform_data/gpio_backlight.h>
 #include <linux/platform_device.h>
 #include <linux/property.h>
 #include <linux/slab.h>
 
 struct gpio_backlight {
-	struct device *dev;
 	struct device *fbdev;
-
 	struct gpio_desc *gpiod;
-	int def_value;
 };
 
-static int gpio_backlight_update_status(struct backlight_device *bl)
+static int gpio_backlight_get_next_brightness(struct backlight_device *bl)
 {
-	struct gpio_backlight *gbl = bl_get_data(bl);
 	int brightness = bl->props.brightness;
 
 	if (bl->props.power != FB_BLANK_UNBLANK ||
@@ -36,6 +30,14 @@ static int gpio_backlight_update_status(struct backlight_device *bl)
 	    bl->props.state & (BL_CORE_SUSPENDED | BL_CORE_FBBLANK))
 		brightness = 0;
 
+	return brightness;
+}
+
+static int gpio_backlight_update_status(struct backlight_device *bl)
+{
+	struct gpio_backlight *gbl = bl_get_data(bl);
+	int brightness = gpio_backlight_get_next_brightness(bl);
+
 	gpiod_set_value_cansleep(gbl->gpiod, brightness);
 
 	return 0;
@@ -55,105 +57,63 @@ static const struct backlight_ops gpio_backlight_ops = {
 	.check_fb	= gpio_backlight_check_fb,
 };
 
-static int gpio_backlight_probe_dt(struct platform_device *pdev,
-				   struct gpio_backlight *gbl)
-{
-	struct device *dev = &pdev->dev;
-	int ret;
-
-	gbl->def_value = device_property_read_bool(dev, "default-on");
-
-	gbl->gpiod = devm_gpiod_get(dev, NULL, GPIOD_ASIS);
-	if (IS_ERR(gbl->gpiod)) {
-		ret = PTR_ERR(gbl->gpiod);
-
-		if (ret != -EPROBE_DEFER) {
-			dev_err(dev,
-				"Error: The gpios parameter is missing or invalid.\n");
-		}
-		return ret;
-	}
-
-	return 0;
-}
-
-static int gpio_backlight_initial_power_state(struct gpio_backlight *gbl)
-{
-	struct device_node *node = gbl->dev->of_node;
-
-	/* Not booted with device tree or no phandle link to the node */
-	if (!node || !node->phandle)
-		return gbl->def_value ? FB_BLANK_UNBLANK : FB_BLANK_POWERDOWN;
-
-	/* if the enable GPIO is disabled, do not enable the backlight */
-	if (gpiod_get_value_cansleep(gbl->gpiod) == 0)
-		return FB_BLANK_POWERDOWN;
-
-	return FB_BLANK_UNBLANK;
-}
-
-
 static int gpio_backlight_probe(struct platform_device *pdev)
 {
-	struct gpio_backlight_platform_data *pdata =
-		dev_get_platdata(&pdev->dev);
+	struct device *dev = &pdev->dev;
+	struct gpio_backlight_platform_data *pdata = dev_get_platdata(dev);
+	struct device_node *of_node = dev->of_node;
 	struct backlight_properties props;
 	struct backlight_device *bl;
 	struct gpio_backlight *gbl;
-	int ret;
+	int ret, init_brightness, def_value;
 
-	gbl = devm_kzalloc(&pdev->dev, sizeof(*gbl), GFP_KERNEL);
+	gbl = devm_kzalloc(dev, sizeof(*gbl), GFP_KERNEL);
 	if (gbl == NULL)
 		return -ENOMEM;
 
-	gbl->dev = &pdev->dev;
+	if (pdata)
+		gbl->fbdev = pdata->fbdev;
 
-	if (pdev->dev.fwnode) {
-		ret = gpio_backlight_probe_dt(pdev, gbl);
-		if (ret)
-			return ret;
-	} else if (pdata) {
-		/*
-		 * Legacy platform data GPIO retrieveal. Do not expand
-		 * the use of this code path, currently only used by one
-		 * SH board.
-		 */
-		unsigned long flags = GPIOF_DIR_OUT;
+	def_value = device_property_read_bool(dev, "default-on");
 
-		gbl->fbdev = pdata->fbdev;
-		gbl->def_value = pdata->def_value;
-		flags |= gbl->def_value ? GPIOF_INIT_HIGH : GPIOF_INIT_LOW;
-
-		ret = devm_gpio_request_one(gbl->dev, pdata->gpio, flags,
-					    pdata ? pdata->name : "backlight");
-		if (ret < 0) {
-			dev_err(&pdev->dev, "unable to request GPIO\n");
-			return ret;
-		}
-		gbl->gpiod = gpio_to_desc(pdata->gpio);
-		if (!gbl->gpiod)
-			return -EINVAL;
-	} else {
-		dev_err(&pdev->dev,
-			"failed to find platform data or device tree node.\n");
-		return -ENODEV;
+	gbl->gpiod = devm_gpiod_get(dev, NULL, GPIOD_ASIS);
+	if (IS_ERR(gbl->gpiod)) {
+		ret = PTR_ERR(gbl->gpiod);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev,
+				"Error: The gpios parameter is missing or invalid.\n");
+		return ret;
 	}
 
 	memset(&props, 0, sizeof(props));
 	props.type = BACKLIGHT_RAW;
 	props.max_brightness = 1;
-	bl = devm_backlight_device_register(&pdev->dev, dev_name(&pdev->dev),
-					&pdev->dev, gbl, &gpio_backlight_ops,
-					&props);
+	bl = devm_backlight_device_register(dev, dev_name(dev), dev, gbl,
+					    &gpio_backlight_ops, &props);
 	if (IS_ERR(bl)) {
-		dev_err(&pdev->dev, "failed to register backlight\n");
+		dev_err(dev, "failed to register backlight\n");
 		return PTR_ERR(bl);
 	}
 
-	bl->props.power = gpio_backlight_initial_power_state(gbl);
+	/* Set the initial power state */
+	if (!of_node || !of_node->phandle)
+		/* Not booted with device tree or no phandle link to the node */
+		bl->props.power = def_value ? FB_BLANK_UNBLANK
+					    : FB_BLANK_POWERDOWN;
+	else if (gpiod_get_direction(gbl->gpiod) == 0 &&
+		 gpiod_get_value_cansleep(gbl->gpiod) == 0)
+		bl->props.power = FB_BLANK_POWERDOWN;
+	else
+		bl->props.power = FB_BLANK_UNBLANK;
+
 	bl->props.brightness = 1;
 
-	backlight_update_status(bl);
+	init_brightness = gpio_backlight_get_next_brightness(bl);
+	ret = gpiod_direction_output(gbl->gpiod, init_brightness);
+	if (ret) {
+		dev_err(dev, "failed to set initial brightness\n");
+		return ret;
+	}
 
 	platform_set_drvdata(pdev, bl);
 	return 0;
diff --git a/drivers/video/backlight/ipaq_micro_bl.c b/drivers/video/backlight/ipaq_micro_bl.c
index 1123f67c12b3..85b16cc82878 100644
--- a/drivers/video/backlight/ipaq_micro_bl.c
+++ b/drivers/video/backlight/ipaq_micro_bl.c
@@ -44,7 +44,7 @@ static const struct backlight_ops micro_bl_ops = {
 	.update_status  = micro_bl_update_status,
 };
 
-static struct backlight_properties micro_bl_props = {
+static const struct backlight_properties micro_bl_props = {
 	.type = BACKLIGHT_RAW,
 	.max_brightness = 255,
 	.power = FB_BLANK_UNBLANK,
diff --git a/drivers/video/backlight/lm3630a_bl.c b/drivers/video/backlight/lm3630a_bl.c
index 2d8e8192e4e2..ee320883b710 100644
--- a/drivers/video/backlight/lm3630a_bl.c
+++ b/drivers/video/backlight/lm3630a_bl.c
@@ -12,6 +12,7 @@
 #include <linux/uaccess.h>
 #include <linux/interrupt.h>
 #include <linux/regmap.h>
+#include <linux/gpio/consumer.h>
 #include <linux/pwm.h>
 #include <linux/platform_data/lm3630a_bl.h>
 
@@ -48,6 +49,7 @@ struct lm3630a_chip {
 	struct lm3630a_platform_data *pdata;
 	struct backlight_device *bleda;
 	struct backlight_device *bledb;
+	struct gpio_desc *enable_gpio;
 	struct regmap *regmap;
 	struct pwm_device *pwmd;
 };
@@ -534,6 +536,13 @@ static int lm3630a_probe(struct i2c_client *client,
 	}
 	pchip->pdata = pdata;
 
+	pchip->enable_gpio = devm_gpiod_get_optional(&client->dev, "enable",
+						GPIOD_OUT_HIGH);
+	if (IS_ERR(pchip->enable_gpio)) {
+		rval = PTR_ERR(pchip->enable_gpio);
+		return rval;
+	}
+
 	/* chip initialize */
 	rval = lm3630a_chip_init(pchip);
 	if (rval < 0) {
@@ -598,12 +607,14 @@ static const struct i2c_device_id lm3630a_id[] = {
 	{}
 };
 
+MODULE_DEVICE_TABLE(i2c, lm3630a_id);
+
 static const struct of_device_id lm3630a_match_table[] = {
 	{ .compatible = "ti,lm3630a", },
 	{ },
 };
 
-MODULE_DEVICE_TABLE(i2c, lm3630a_id);
+MODULE_DEVICE_TABLE(of, lm3630a_match_table);
 
 static struct i2c_driver lm3630a_i2c_driver = {
 	.driver = {
diff --git a/drivers/video/backlight/pm8941-wled.c b/drivers/video/backlight/pm8941-wled.c
deleted file mode 100644
index 82b85725a22a..000000000000
--- a/drivers/video/backlight/pm8941-wled.c
+++ /dev/null
@@ -1,424 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/* Copyright (c) 2015, Sony Mobile Communications, AB.
- */
-
-#include <linux/kernel.h>
-#include <linux/backlight.h>
-#include <linux/module.h>
-#include <linux/of.h>
-#include <linux/of_device.h>
-#include <linux/regmap.h>
-
-/* From DT binding */
-#define PM8941_WLED_DEFAULT_BRIGHTNESS		2048
-
-#define PM8941_WLED_REG_VAL_BASE		0x40
-#define  PM8941_WLED_REG_VAL_MAX		0xFFF
-
-#define PM8941_WLED_REG_MOD_EN			0x46
-#define  PM8941_WLED_REG_MOD_EN_BIT		BIT(7)
-#define  PM8941_WLED_REG_MOD_EN_MASK		BIT(7)
-
-#define PM8941_WLED_REG_SYNC			0x47
-#define  PM8941_WLED_REG_SYNC_MASK		0x07
-#define  PM8941_WLED_REG_SYNC_LED1		BIT(0)
-#define  PM8941_WLED_REG_SYNC_LED2		BIT(1)
-#define  PM8941_WLED_REG_SYNC_LED3		BIT(2)
-#define  PM8941_WLED_REG_SYNC_ALL		0x07
-#define  PM8941_WLED_REG_SYNC_CLEAR		0x00
-
-#define PM8941_WLED_REG_FREQ			0x4c
-#define  PM8941_WLED_REG_FREQ_MASK		0x0f
-
-#define PM8941_WLED_REG_OVP			0x4d
-#define  PM8941_WLED_REG_OVP_MASK		0x03
-
-#define PM8941_WLED_REG_BOOST			0x4e
-#define  PM8941_WLED_REG_BOOST_MASK		0x07
-
-#define PM8941_WLED_REG_SINK			0x4f
-#define  PM8941_WLED_REG_SINK_MASK		0xe0
-#define  PM8941_WLED_REG_SINK_SHFT		0x05
-
-/* Per-'string' registers below */
-#define PM8941_WLED_REG_STR_OFFSET		0x10
-
-#define PM8941_WLED_REG_STR_MOD_EN_BASE		0x60
-#define  PM8941_WLED_REG_STR_MOD_MASK		BIT(7)
-#define  PM8941_WLED_REG_STR_MOD_EN		BIT(7)
-
-#define PM8941_WLED_REG_STR_SCALE_BASE		0x62
-#define  PM8941_WLED_REG_STR_SCALE_MASK		0x1f
-
-#define PM8941_WLED_REG_STR_MOD_SRC_BASE	0x63
-#define  PM8941_WLED_REG_STR_MOD_SRC_MASK	0x01
-#define  PM8941_WLED_REG_STR_MOD_SRC_INT	0x00
-#define  PM8941_WLED_REG_STR_MOD_SRC_EXT	0x01
-
-#define PM8941_WLED_REG_STR_CABC_BASE		0x66
-#define  PM8941_WLED_REG_STR_CABC_MASK		BIT(7)
-#define  PM8941_WLED_REG_STR_CABC_EN		BIT(7)
-
-struct pm8941_wled_config {
-	u32 i_boost_limit;
-	u32 ovp;
-	u32 switch_freq;
-	u32 num_strings;
-	u32 i_limit;
-	bool cs_out_en;
-	bool ext_gen;
-	bool cabc_en;
-};
-
-struct pm8941_wled {
-	const char *name;
-	struct regmap *regmap;
-	u16 addr;
-
-	struct pm8941_wled_config cfg;
-};
-
-static int pm8941_wled_update_status(struct backlight_device *bl)
-{
-	struct pm8941_wled *wled = bl_get_data(bl);
-	u16 val = bl->props.brightness;
-	u8 ctrl = 0;
-	int rc;
-	int i;
-
-	if (bl->props.power != FB_BLANK_UNBLANK ||
-	    bl->props.fb_blank != FB_BLANK_UNBLANK ||
-	    bl->props.state & BL_CORE_FBBLANK)
-		val = 0;
-
-	if (val != 0)
-		ctrl = PM8941_WLED_REG_MOD_EN_BIT;
-
-	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_MOD_EN,
-			PM8941_WLED_REG_MOD_EN_MASK, ctrl);
-	if (rc)
-		return rc;
-
-	for (i = 0; i < wled->cfg.num_strings; ++i) {
-		u8 v[2] = { val & 0xff, (val >> 8) & 0xf };
-
-		rc = regmap_bulk_write(wled->regmap,
-				wled->addr + PM8941_WLED_REG_VAL_BASE + 2 * i,
-				v, 2);
-		if (rc)
-			return rc;
-	}
-
-	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_SYNC,
-			PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_ALL);
-	if (rc)
-		return rc;
-
-	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_SYNC,
-			PM8941_WLED_REG_SYNC_MASK, PM8941_WLED_REG_SYNC_CLEAR);
-	return rc;
-}
-
-static int pm8941_wled_setup(struct pm8941_wled *wled)
-{
-	int rc;
-	int i;
-
-	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_OVP,
-			PM8941_WLED_REG_OVP_MASK, wled->cfg.ovp);
-	if (rc)
-		return rc;
-
-	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_BOOST,
-			PM8941_WLED_REG_BOOST_MASK, wled->cfg.i_boost_limit);
-	if (rc)
-		return rc;
-
-	rc = regmap_update_bits(wled->regmap,
-			wled->addr + PM8941_WLED_REG_FREQ,
-			PM8941_WLED_REG_FREQ_MASK, wled->cfg.switch_freq);
-	if (rc)
-		return rc;
-
-	if (wled->cfg.cs_out_en) {
-		u8 all = (BIT(wled->cfg.num_strings) - 1)
-				<< PM8941_WLED_REG_SINK_SHFT;
-
-		rc = regmap_update_bits(wled->regmap,
-				wled->addr + PM8941_WLED_REG_SINK,
-				PM8941_WLED_REG_SINK_MASK, all);
-		if (rc)
-			return rc;
-	}
-
-	for (i = 0; i < wled->cfg.num_strings; ++i) {
-		u16 addr = wled->addr + PM8941_WLED_REG_STR_OFFSET * i;
-
-		rc = regmap_update_bits(wled->regmap,
-				addr + PM8941_WLED_REG_STR_MOD_EN_BASE,
-				PM8941_WLED_REG_STR_MOD_MASK,
-				PM8941_WLED_REG_STR_MOD_EN);
-		if (rc)
-			return rc;
-
-		if (wled->cfg.ext_gen) {
-			rc = regmap_update_bits(wled->regmap,
-					addr + PM8941_WLED_REG_STR_MOD_SRC_BASE,
-					PM8941_WLED_REG_STR_MOD_SRC_MASK,
-					PM8941_WLED_REG_STR_MOD_SRC_EXT);
-			if (rc)
-				return rc;
-		}
-
-		rc = regmap_update_bits(wled->regmap,
-				addr + PM8941_WLED_REG_STR_SCALE_BASE,
-				PM8941_WLED_REG_STR_SCALE_MASK,
-				wled->cfg.i_limit);
-		if (rc)
-			return rc;
-
-		rc = regmap_update_bits(wled->regmap,
-				addr + PM8941_WLED_REG_STR_CABC_BASE,
-				PM8941_WLED_REG_STR_CABC_MASK,
-				wled->cfg.cabc_en ?
-					PM8941_WLED_REG_STR_CABC_EN : 0);
-		if (rc)
-			return rc;
-	}
-
-	return 0;
-}
-
-static const struct pm8941_wled_config pm8941_wled_config_defaults = {
-	.i_boost_limit = 3,
-	.i_limit = 20,
-	.ovp = 2,
-	.switch_freq = 5,
-	.num_strings = 0,
-	.cs_out_en = false,
-	.ext_gen = false,
-	.cabc_en = false,
-};
-
-struct pm8941_wled_var_cfg {
-	const u32 *values;
-	u32 (*fn)(u32);
-	int size;
-};
-
-static const u32 pm8941_wled_i_boost_limit_values[] = {
-	105, 385, 525, 805, 980, 1260, 1400, 1680,
-};
-
-static const struct pm8941_wled_var_cfg pm8941_wled_i_boost_limit_cfg = {
-	.values = pm8941_wled_i_boost_limit_values,
-	.size = ARRAY_SIZE(pm8941_wled_i_boost_limit_values),
-};
-
-static const u32 pm8941_wled_ovp_values[] = {
-	35, 32, 29, 27,
-};
-
-static const struct pm8941_wled_var_cfg pm8941_wled_ovp_cfg = {
-	.values = pm8941_wled_ovp_values,
-	.size = ARRAY_SIZE(pm8941_wled_ovp_values),
-};
-
-static u32 pm8941_wled_num_strings_values_fn(u32 idx)
-{
-	return idx + 1;
-}
-
-static const struct pm8941_wled_var_cfg pm8941_wled_num_strings_cfg = {
-	.fn = pm8941_wled_num_strings_values_fn,
-	.size = 3,
-};
-
-static u32 pm8941_wled_switch_freq_values_fn(u32 idx)
-{
-	return 19200 / (2 * (1 + idx));
-}
-
-static const struct pm8941_wled_var_cfg pm8941_wled_switch_freq_cfg = {
-	.fn = pm8941_wled_switch_freq_values_fn,
-	.size = 16,
-};
-
-static const struct pm8941_wled_var_cfg pm8941_wled_i_limit_cfg = {
-	.size = 26,
-};
-
-static u32 pm8941_wled_values(const struct pm8941_wled_var_cfg *cfg, u32 idx)
-{
-	if (idx >= cfg->size)
-		return UINT_MAX;
-	if (cfg->fn)
-		return cfg->fn(idx);
-	if (cfg->values)
-		return cfg->values[idx];
-	return idx;
-}
-
-static int pm8941_wled_configure(struct pm8941_wled *wled, struct device *dev)
-{
-	struct pm8941_wled_config *cfg = &wled->cfg;
-	u32 val;
-	int rc;
-	u32 c;
-	int i;
-	int j;
-
-	const struct {
-		const char *name;
-		u32 *val_ptr;
-		const struct pm8941_wled_var_cfg *cfg;
-	} u32_opts[] = {
-		{
-			"qcom,current-boost-limit",
-			&cfg->i_boost_limit,
-			.cfg = &pm8941_wled_i_boost_limit_cfg,
-		},
-		{
-			"qcom,current-limit",
-			&cfg->i_limit,
-			.cfg = &pm8941_wled_i_limit_cfg,
-		},
-		{
-			"qcom,ovp",
-			&cfg->ovp,
-			.cfg = &pm8941_wled_ovp_cfg,
-		},
-		{
-			"qcom,switching-freq",
-			&cfg->switch_freq,
-			.cfg = &pm8941_wled_switch_freq_cfg,
-		},
-		{
-			"qcom,num-strings",
-			&cfg->num_strings,
-			.cfg = &pm8941_wled_num_strings_cfg,
-		},
-	};
-	const struct {
-		const char *name;
-		bool *val_ptr;
-	} bool_opts[] = {
-		{ "qcom,cs-out", &cfg->cs_out_en, },
-		{ "qcom,ext-gen", &cfg->ext_gen, },
-		{ "qcom,cabc", &cfg->cabc_en, },
-	};
-
-	rc = of_property_read_u32(dev->of_node, "reg", &val);
-	if (rc || val > 0xffff) {
-		dev_err(dev, "invalid IO resources\n");
-		return rc ? rc : -EINVAL;
-	}
-	wled->addr = val;
-
-	rc = of_property_read_string(dev->of_node, "label", &wled->name);
-	if (rc)
-		wled->name = devm_kasprintf(dev, GFP_KERNEL, "%pOFn", dev->of_node);
-
-	*cfg = pm8941_wled_config_defaults;
-	for (i = 0; i < ARRAY_SIZE(u32_opts); ++i) {
-		rc = of_property_read_u32(dev->of_node, u32_opts[i].name, &val);
-		if (rc == -EINVAL) {
-			continue;
-		} else if (rc) {
-			dev_err(dev, "error reading '%s'\n", u32_opts[i].name);
-			return rc;
-		}
-
-		c = UINT_MAX;
-		for (j = 0; c != val; j++) {
-			c = pm8941_wled_values(u32_opts[i].cfg, j);
-			if (c == UINT_MAX) {
-				dev_err(dev, "invalid value for '%s'\n",
-					u32_opts[i].name);
-				return -EINVAL;
-			}
-		}
-
-		dev_dbg(dev, "'%s' = %u\n", u32_opts[i].name, c);
-		*u32_opts[i].val_ptr = j;
-	}
-
-	for (i = 0; i < ARRAY_SIZE(bool_opts); ++i) {
-		if (of_property_read_bool(dev->of_node, bool_opts[i].name))
-			*bool_opts[i].val_ptr = true;
-	}
-
-	cfg->num_strings = cfg->num_strings + 1;
-
-	return 0;
-}
-
-static const struct backlight_ops pm8941_wled_ops = {
-	.update_status = pm8941_wled_update_status,
-};
-
-static int pm8941_wled_probe(struct platform_device *pdev)
-{
-	struct backlight_properties props;
-	struct backlight_device *bl;
-	struct pm8941_wled *wled;
-	struct regmap *regmap;
-	u32 val;
-	int rc;
-
-	regmap = dev_get_regmap(pdev->dev.parent, NULL);
-	if (!regmap) {
-		dev_err(&pdev->dev, "Unable to get regmap\n");
-		return -EINVAL;
-	}
-
-	wled = devm_kzalloc(&pdev->dev, sizeof(*wled), GFP_KERNEL);
-	if (!wled)
-		return -ENOMEM;
-
-	wled->regmap = regmap;
-
-	rc = pm8941_wled_configure(wled, &pdev->dev);
-	if (rc)
-		return rc;
-
-	rc = pm8941_wled_setup(wled);
-	if (rc)
-		return rc;
-
-	val = PM8941_WLED_DEFAULT_BRIGHTNESS;
-	of_property_read_u32(pdev->dev.of_node, "default-brightness", &val);
-
-	memset(&props, 0, sizeof(struct backlight_properties));
-	props.type = BACKLIGHT_RAW;
-	props.brightness = val;
-	props.max_brightness = PM8941_WLED_REG_VAL_MAX;
-	bl = devm_backlight_device_register(&pdev->dev, wled->name,
-					    &pdev->dev, wled,
-					    &pm8941_wled_ops, &props);
-	return PTR_ERR_OR_ZERO(bl);
-};
-
-static const struct of_device_id pm8941_wled_match_table[] = {
-	{ .compatible = "qcom,pm8941-wled" },
-	{}
-};
-MODULE_DEVICE_TABLE(of, pm8941_wled_match_table);
-
-static struct platform_driver pm8941_wled_driver = {
-	.probe = pm8941_wled_probe,
-	.driver	= {
-		.name = "pm8941-wled",
-		.of_match_table	= pm8941_wled_match_table,
-	},
-};
-
-module_platform_driver(pm8941_wled_driver);
-
-MODULE_DESCRIPTION("pm8941 wled driver");
-MODULE_LICENSE("GPL v2");
diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c
index 746eebc411df..efb4efc2a13d 100644
--- a/drivers/video/backlight/pwm_bl.c
+++ b/drivers/video/backlight/pwm_bl.c
@@ -125,8 +125,9 @@ static int pwm_backlight_update_status(struct backlight_device *bl)
 		state.duty_cycle = compute_duty_cycle(pb, brightness);
 		pwm_apply_state(pb->pwm, &state);
 		pwm_backlight_power_on(pb);
-	} else
+	} else {
 		pwm_backlight_power_off(pb);
+	}
 
 	if (pb->notify_after)
 		pb->notify_after(pb->dev, brightness);
@@ -148,15 +149,16 @@ static const struct backlight_ops pwm_backlight_ops = {
 };
 
 #ifdef CONFIG_OF
-#define PWM_LUMINANCE_SCALE	10000 /* luminance scale */
+#define PWM_LUMINANCE_SHIFT	16
+#define PWM_LUMINANCE_SCALE	(1 << PWM_LUMINANCE_SHIFT) /* luminance scale */
 
 /*
  * CIE lightness to PWM conversion.
  *
  * The CIE 1931 lightness formula is what actually describes how we perceive
  * light:
- *          Y = (L* / 902.3)           if L* ≤ 0.08856
- *          Y = ((L* + 16) / 116)^3    if L* > 0.08856
+ *          Y = (L* / 903.3)           if L* ≤ 8
+ *          Y = ((L* + 16) / 116)^3    if L* > 8
  *
  * Where Y is the luminance, the amount of light coming out of the screen, and
  * is a number between 0.0 and 1.0; and L* is the lightness, how bright a human
@@ -165,16 +167,25 @@ static const struct backlight_ops pwm_backlight_ops = {
  * The following function does the fixed point maths needed to implement the
  * above formula.
  */
-static u64 cie1931(unsigned int lightness, unsigned int scale)
+static u64 cie1931(unsigned int lightness)
 {
 	u64 retval;
 
+	/*
+	 * @lightness is given as a number between 0 and 1, expressed
+	 * as a fixed-point number in scale
+	 * PWM_LUMINANCE_SCALE. Convert to a percentage, still
+	 * expressed as a fixed-point number, so the above formulas
+	 * can be applied.
+	 */
 	lightness *= 100;
-	if (lightness <= (8 * scale)) {
-		retval = DIV_ROUND_CLOSEST_ULL(lightness * 10, 9023);
+	if (lightness <= (8 * PWM_LUMINANCE_SCALE)) {
+		retval = DIV_ROUND_CLOSEST(lightness * 10, 9033);
 	} else {
-		retval = int_pow((lightness + (16 * scale)) / 116, 3);
-		retval = DIV_ROUND_CLOSEST_ULL(retval, (scale * scale));
+		retval = (lightness + (16 * PWM_LUMINANCE_SCALE)) / 116;
+		retval *= retval * retval;
+		retval += 1ULL << (2*PWM_LUMINANCE_SHIFT - 1);
+		retval >>= 2*PWM_LUMINANCE_SHIFT;
 	}
 
 	return retval;
@@ -208,8 +219,7 @@ int pwm_backlight_brightness_default(struct device *dev,
 	/* Fill the table using the cie1931 algorithm */
 	for (i = 0; i < data->max_brightness; i++) {
 		retval = cie1931((i * PWM_LUMINANCE_SCALE) /
-				 data->max_brightness, PWM_LUMINANCE_SCALE) *
-				 period;
+				 data->max_brightness) * period;
 		retval = DIV_ROUND_CLOSEST_ULL(retval, PWM_LUMINANCE_SCALE);
 		if (retval > UINT_MAX)
 			return -EINVAL;
@@ -564,18 +574,17 @@ static int pwm_backlight_probe(struct platform_device *pdev)
 	memset(&props, 0, sizeof(struct backlight_properties));
 
 	if (data->levels) {
+		pb->levels = data->levels;
+
 		/*
 		 * For the DT case, only when brightness levels is defined
 		 * data->levels is filled. For the non-DT case, data->levels
 		 * can come from platform data, however is not usual.
 		 */
-		for (i = 0; i <= data->max_brightness; i++) {
+		for (i = 0; i <= data->max_brightness; i++)
 			if (data->levels[i] > pb->scale)
 				pb->scale = data->levels[i];
 
-			pb->levels = data->levels;
-		}
-
 		if (pwm_backlight_is_linear(data))
 			props.scale = BACKLIGHT_SCALE_LINEAR;
 		else
diff --git a/drivers/video/backlight/qcom-wled.c b/drivers/video/backlight/qcom-wled.c
new file mode 100644
index 000000000000..d46052d8ff41
--- /dev/null
+++ b/drivers/video/backlight/qcom-wled.c
@@ -0,0 +1,1296 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright (c) 2015, Sony Mobile Communications, AB.
+ */
+
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/ktime.h>
+#include <linux/kernel.h>
+#include <linux/backlight.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_address.h>
+#include <linux/regmap.h>
+
+/* From DT binding */
+#define WLED_MAX_STRINGS				4
+
+#define WLED_DEFAULT_BRIGHTNESS				2048
+#define WLED_SOFT_START_DLY_US				10000
+#define WLED3_SINK_REG_BRIGHT_MAX			0xFFF
+
+/* WLED3/WLED4 control registers */
+#define WLED3_CTRL_REG_FAULT_STATUS			0x08
+#define  WLED3_CTRL_REG_ILIM_FAULT_BIT			BIT(0)
+#define  WLED3_CTRL_REG_OVP_FAULT_BIT			BIT(1)
+#define  WLED4_CTRL_REG_SC_FAULT_BIT			BIT(2)
+
+#define WLED3_CTRL_REG_INT_RT_STS			0x10
+#define  WLED3_CTRL_REG_OVP_FAULT_STATUS		BIT(1)
+
+#define WLED3_CTRL_REG_MOD_EN				0x46
+#define  WLED3_CTRL_REG_MOD_EN_MASK			BIT(7)
+#define  WLED3_CTRL_REG_MOD_EN_SHIFT			7
+
+#define WLED3_CTRL_REG_FEEDBACK_CONTROL			0x48
+
+#define WLED3_CTRL_REG_FREQ				0x4c
+#define  WLED3_CTRL_REG_FREQ_MASK			GENMASK(3, 0)
+
+#define WLED3_CTRL_REG_OVP				0x4d
+#define  WLED3_CTRL_REG_OVP_MASK			GENMASK(1, 0)
+
+#define WLED3_CTRL_REG_ILIMIT				0x4e
+#define  WLED3_CTRL_REG_ILIMIT_MASK			GENMASK(2, 0)
+
+/* WLED3/WLED4 sink registers */
+#define WLED3_SINK_REG_SYNC				0x47
+#define  WLED3_SINK_REG_SYNC_CLEAR			0x00
+
+#define WLED3_SINK_REG_CURR_SINK			0x4f
+#define  WLED3_SINK_REG_CURR_SINK_MASK			GENMASK(7, 5)
+#define  WLED3_SINK_REG_CURR_SINK_SHFT			5
+
+/* WLED3 specific per-'string' registers below */
+#define WLED3_SINK_REG_BRIGHT(n)			(0x40 + n)
+
+#define WLED3_SINK_REG_STR_MOD_EN(n)			(0x60 + (n * 0x10))
+#define  WLED3_SINK_REG_STR_MOD_MASK			BIT(7)
+
+#define WLED3_SINK_REG_STR_FULL_SCALE_CURR(n)		(0x62 + (n * 0x10))
+#define  WLED3_SINK_REG_STR_FULL_SCALE_CURR_MASK	GENMASK(4, 0)
+
+#define WLED3_SINK_REG_STR_MOD_SRC(n)			(0x63 + (n * 0x10))
+#define  WLED3_SINK_REG_STR_MOD_SRC_MASK		BIT(0)
+#define  WLED3_SINK_REG_STR_MOD_SRC_INT			0x00
+#define  WLED3_SINK_REG_STR_MOD_SRC_EXT			0x01
+
+#define WLED3_SINK_REG_STR_CABC(n)			(0x66 + (n * 0x10))
+#define  WLED3_SINK_REG_STR_CABC_MASK			BIT(7)
+
+/* WLED4 specific control registers */
+#define WLED4_CTRL_REG_SHORT_PROTECT			0x5e
+#define  WLED4_CTRL_REG_SHORT_EN_MASK			BIT(7)
+
+#define WLED4_CTRL_REG_SEC_ACCESS			0xd0
+#define  WLED4_CTRL_REG_SEC_UNLOCK			0xa5
+
+#define WLED4_CTRL_REG_TEST1				0xe2
+#define  WLED4_CTRL_REG_TEST1_EXT_FET_DTEST2		0x09
+
+/* WLED4 specific sink registers */
+#define WLED4_SINK_REG_CURR_SINK			0x46
+#define  WLED4_SINK_REG_CURR_SINK_MASK			GENMASK(7, 4)
+#define  WLED4_SINK_REG_CURR_SINK_SHFT			4
+
+/* WLED4 specific per-'string' registers below */
+#define WLED4_SINK_REG_STR_MOD_EN(n)			(0x50 + (n * 0x10))
+#define  WLED4_SINK_REG_STR_MOD_MASK			BIT(7)
+
+#define WLED4_SINK_REG_STR_FULL_SCALE_CURR(n)		(0x52 + (n * 0x10))
+#define  WLED4_SINK_REG_STR_FULL_SCALE_CURR_MASK	GENMASK(3, 0)
+
+#define WLED4_SINK_REG_STR_MOD_SRC(n)			(0x53 + (n * 0x10))
+#define  WLED4_SINK_REG_STR_MOD_SRC_MASK		BIT(0)
+#define  WLED4_SINK_REG_STR_MOD_SRC_INT			0x00
+#define  WLED4_SINK_REG_STR_MOD_SRC_EXT			0x01
+
+#define WLED4_SINK_REG_STR_CABC(n)			(0x56 + (n * 0x10))
+#define  WLED4_SINK_REG_STR_CABC_MASK			BIT(7)
+
+#define WLED4_SINK_REG_BRIGHT(n)			(0x57 + (n * 0x10))
+
+struct wled_var_cfg {
+	const u32 *values;
+	u32 (*fn)(u32);
+	int size;
+};
+
+struct wled_u32_opts {
+	con