Merge tag 'backlight-next-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight

Pull backlight updates from Lee Jones:
 "New Functionality:

   - Ensure correct includes are present and remove some that are not
     required

   - Drop redundant of_match_ptr() call to cast pointer to NULL

  Bug Fixes:

   - Revert to old (expected) behaviour of initialising PWM state on
     first brightness change

   - Correctly handle / propagate errors

   - Fix 'sometimes-uninitialised' issues"

* tag 'backlight-next-6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: led_bl: Remove redundant of_match_ptr()
  backlight: lp855x: Drop ret variable in brightness change function
  backlight: gpio_backlight: Drop output GPIO direction check for initial power state
  backlight: lp855x: Catch errors when changing brightness
  backlight: lp855x: Initialize PWM state on first brightness change
  backlight: qcom-wled: Explicitly include correct DT includes

Author: torvalds

drivers/video/backlight/gpio_backlight.c

@@ -87,8 +87,7 @@ static int gpio_backlight_probe(struct platform_device *pdev)
 		/* 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)
+	else if (gpiod_get_value_cansleep(gbl->gpiod) == 0)
 		bl->props.power = FB_BLANK_POWERDOWN;
 	else
 		bl->props.power = FB_BLANK_UNBLANK;

drivers/video/backlight/led_bl.c

@@ -243,7 +243,7 @@ MODULE_DEVICE_TABLE(of, led_bl_of_match);
 static struct platform_driver led_bl_driver = {
 	.driver		= {
 		.name		= "led-backlight",
-		.of_match_table	= of_match_ptr(led_bl_of_match),
+		.of_match_table	= led_bl_of_match,
 	},
 	.probe		= led_bl_probe,
 	.remove_new	= led_bl_remove,

drivers/video/backlight/lp855x_bl.c

@@ -71,6 +71,7 @@ struct lp855x {
 	struct device *dev;
 	struct lp855x_platform_data *pdata;
 	struct pwm_device *pwm;
+	bool needs_pwm_init;
 	struct regulator *supply;	/* regulator for VDD input */
 	struct regulator *enable;	/* regulator for EN/VDDIO input */
 };
@@ -216,16 +217,24 @@ static int lp855x_configure(struct lp855x *lp)
 	return ret;
 }
 
-static void lp855x_pwm_ctrl(struct lp855x *lp, int br, int max_br)
+static int lp855x_pwm_ctrl(struct lp855x *lp, int br, int max_br)
 {
 	struct pwm_state state;
 
-	pwm_get_state(lp->pwm, &state);
+	if (lp->needs_pwm_init) {
+		pwm_init_state(lp->pwm, &state);
+		/* Legacy platform data compatibility */
+		if (lp->pdata->period_ns > 0)
+			state.period = lp->pdata->period_ns;
+		lp->needs_pwm_init = false;
+	} else {
+		pwm_get_state(lp->pwm, &state);
+	}
 
 	state.duty_cycle = div_u64(br * state.period, max_br);
 	state.enabled = state.duty_cycle;
 
-	pwm_apply_state(lp->pwm, &state);
+	return pwm_apply_state(lp->pwm, &state);
 }
 
 static int lp855x_bl_update_status(struct backlight_device *bl)
@@ -237,11 +246,12 @@ static int lp855x_bl_update_status(struct backlight_device *bl)
 		brightness = 0;
 
 	if (lp->mode == PWM_BASED)
-		lp855x_pwm_ctrl(lp, brightness, bl->props.max_brightness);
+		return lp855x_pwm_ctrl(lp, brightness,
+				      bl->props.max_brightness);
 	else if (lp->mode == REGISTER_BASED)
-		lp855x_write_byte(lp, lp->cfg->reg_brightness, (u8)brightness);
-
-	return 0;
+		return lp855x_write_byte(lp, lp->cfg->reg_brightness,
+					(u8)brightness);
+	return -EINVAL;
 }
 
 static const struct backlight_ops lp855x_bl_ops = {
@@ -387,7 +397,6 @@ static int lp855x_probe(struct i2c_client *cl)
 	const struct i2c_device_id *id = i2c_client_get_device_id(cl);
 	const struct acpi_device_id *acpi_id = NULL;
 	struct device *dev = &cl->dev;
-	struct pwm_state pwmstate;
 	struct lp855x *lp;
 	int ret;
 
@@ -470,15 +479,11 @@ static int lp855x_probe(struct i2c_client *cl)
 		else
 			return dev_err_probe(dev, ret, "getting PWM\n");
 
+		lp->needs_pwm_init = false;
 		lp->mode = REGISTER_BASED;
 		dev_dbg(dev, "mode: register based\n");
 	} else {
-		pwm_init_state(lp->pwm, &pwmstate);
-		/* Legacy platform data compatibility */
-		if (lp->pdata->period_ns > 0)
-			pwmstate.period = lp->pdata->period_ns;
-		pwm_apply_state(lp->pwm, &pwmstate);
-
+		lp->needs_pwm_init = true;
 		lp->mode = PWM_BASED;
 		dev_dbg(dev, "mode: PWM based\n");
 	}

drivers/video/backlight/qcom-wled.c

@@ -9,8 +9,8 @@
 #include <linux/backlight.h>
 #include <linux/module.h>
 #include <linux/of.h>
-#include <linux/of_device.h>
 #include <linux/of_address.h>
+#include <linux/platform_device.h>
 #include <linux/regmap.h>
 
 /* From DT binding */