Merge tag 'backlight-for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight

Pull backlight updates from Lee Jones:
  Fix-ups:
   - Take heed of GPIO default-on requests; gpio_backlight
   - Enable DT probing; tps65217_bl

  Bug Fixes:
   - Free resources in error path; pwm_bl
   - Fix uninitialised variable warning; adp8860_bl, adp8870_bl
   - Protect unconditional DT look-ups from non-DT platforms; pwm_bl
   - Fix backlight flicker; pwm_bl

* tag 'backlight-for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/backlight:
  backlight: pwm_bl: Free PWM requested by legacy API on error path
  backlight: adp8860: Fix another uninitialized variable use
  backlight: gpio-backlight: Use default-on on GPIO request
  backlight: pwm_bl: Fix broken PWM backlight for non-dt platforms
  backlight: tps65217_bl: Add MODULE_DEVICE_TABLE
  backlight: pwm_bl: Avoid backlight flicker when probed from DT
  backlight: adp88x0: Fix uninitialized variable use

drivers/video/backlight/adp8860_bl.c

@@ -566,11 +566,13 @@ static ssize_t adp8860_bl_ambient_light_level_show(struct device *dev,
 
 	mutex_lock(&data->lock);
 	error = adp8860_read(data->client, ADP8860_PH1LEVL, &reg_val);
-	ret_val = reg_val;
-	error |= adp8860_read(data->client, ADP8860_PH1LEVH, &reg_val);
+	if (!error) {
+		ret_val = reg_val;
+		error = adp8860_read(data->client, ADP8860_PH1LEVH, &reg_val);
+	}
 	mutex_unlock(&data->lock);
 
-	if (error < 0)
+	if (error)
 		return error;
 
 	/* Return 13-bit conversion value for the first light sensor */
@@ -621,10 +623,12 @@ static ssize_t adp8860_bl_ambient_light_zone_store(struct device *dev,
 
 		/* Set user supplied ambient light zone */
 		mutex_lock(&data->lock);
-		adp8860_read(data->client, ADP8860_CFGR, &reg_val);
-		reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT);
-		reg_val |= (val - 1) << CFGR_BLV_SHIFT;
-		adp8860_write(data->client, ADP8860_CFGR, reg_val);
+		ret = adp8860_read(data->client, ADP8860_CFGR, &reg_val);
+		if (!ret) {
+			reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT);
+			reg_val |= (val - 1) << CFGR_BLV_SHIFT;
+			adp8860_write(data->client, ADP8860_CFGR, reg_val);
+		}
 		mutex_unlock(&data->lock);
 	}
 

drivers/video/backlight/adp8870_bl.c

@@ -807,10 +807,12 @@ static ssize_t adp8870_bl_ambient_light_zone_store(struct device *dev,
 
 		/* Set user supplied ambient light zone */
 		mutex_lock(&data->lock);
-		adp8870_read(data->client, ADP8870_CFGR, &reg_val);
-		reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT);
-		reg_val |= (val - 1) << CFGR_BLV_SHIFT;
-		adp8870_write(data->client, ADP8870_CFGR, reg_val);
+		ret = adp8870_read(data->client, ADP8870_CFGR, &reg_val);
+		if (!ret) {
+			reg_val &= ~(CFGR_BLV_MASK << CFGR_BLV_SHIFT);
+			reg_val |= (val - 1) << CFGR_BLV_SHIFT;
+			adp8870_write(data->client, ADP8870_CFGR, reg_val);
+		}
 		mutex_unlock(&data->lock);
 	}
 

drivers/video/backlight/gpio_backlight.c

@@ -89,6 +89,7 @@ static int gpio_backlight_probe(struct platform_device *pdev)
 	struct backlight_device *bl;
 	struct gpio_backlight *gbl;
 	struct device_node *np = pdev->dev.of_node;
+	unsigned long flags = GPIOF_DIR_OUT;
 	int ret;
 
 	if (!pdata && !np) {
@@ -114,9 +115,12 @@ static int gpio_backlight_probe(struct platform_device *pdev)
 		gbl->def_value = pdata->def_value;
 	}
 
-	ret = devm_gpio_request_one(gbl->dev, gbl->gpio, GPIOF_DIR_OUT |
-				    (gbl->active ? GPIOF_INIT_LOW
-						 : GPIOF_INIT_HIGH),
+	if (gbl->active)
+		flags |= gbl->def_value ? GPIOF_INIT_HIGH : GPIOF_INIT_LOW;
+	else
+		flags |= gbl->def_value ? GPIOF_INIT_LOW : GPIOF_INIT_HIGH;
+
+	ret = devm_gpio_request_one(gbl->dev, gbl->gpio, flags,
 				    pdata ? pdata->name : "backlight");
 	if (ret < 0) {
 		dev_err(&pdev->dev, "unable to request GPIO\n");

drivers/video/backlight/pwm_bl.c

@@ -198,7 +198,9 @@ static int pwm_backlight_probe(struct platform_device *pdev)
 	struct platform_pwm_backlight_data defdata;
 	struct backlight_properties props;
 	struct backlight_device *bl;
+	struct device_node *node = pdev->dev.of_node;
 	struct pwm_bl_data *pb;
+	int initial_blank = FB_BLANK_UNBLANK;
 	int ret;
 
 	if (!data) {
@@ -242,7 +244,7 @@ static int pwm_backlight_probe(struct platform_device *pdev)
 	pb->enabled = false;
 
 	pb->enable_gpio = devm_gpiod_get_optional(&pdev->dev, "enable",
-						  GPIOD_OUT_HIGH);
+						  GPIOD_ASIS);
 	if (IS_ERR(pb->enable_gpio)) {
 		ret = PTR_ERR(pb->enable_gpio);
 		goto err_alloc;
@@ -264,15 +266,32 @@ static int pwm_backlight_probe(struct platform_device *pdev)
 		pb->enable_gpio = gpio_to_desc(data->enable_gpio);
 	}
 
+	if (pb->enable_gpio) {
+		/*
+		 * If the driver is probed from the device tree and there is a
+		 * phandle link pointing to the backlight node, it is safe to
+		 * assume that another driver will enable the backlight at the
+		 * appropriate time. Therefore, if it is disabled, keep it so.
+		 */
+		if (node && node->phandle &&
+		    gpiod_get_direction(pb->enable_gpio) == GPIOF_DIR_OUT &&
+		    gpiod_get_value(pb->enable_gpio) == 0)
+			initial_blank = FB_BLANK_POWERDOWN;
+		else
+			gpiod_direction_output(pb->enable_gpio, 1);
+	}
+
 	pb->power_supply = devm_regulator_get(&pdev->dev, "power");
 	if (IS_ERR(pb->power_supply)) {
 		ret = PTR_ERR(pb->power_supply);
 		goto err_alloc;
 	}
 
+	if (node && node->phandle && !regulator_is_enabled(pb->power_supply))
+		initial_blank = FB_BLANK_POWERDOWN;
+
 	pb->pwm = devm_pwm_get(&pdev->dev, NULL);
-	if (IS_ERR(pb->pwm) && PTR_ERR(pb->pwm) != -EPROBE_DEFER
-	    && !pdev->dev.of_node) {
+	if (IS_ERR(pb->pwm) && PTR_ERR(pb->pwm) != -EPROBE_DEFER && !node) {
 		dev_err(&pdev->dev, "unable to request PWM, trying legacy API\n");
 		pb->legacy = true;
 		pb->pwm = pwm_request(data->pwm_id, "pwm-backlight");
@@ -309,6 +328,8 @@ static int pwm_backlight_probe(struct platform_device *pdev)
 	if (IS_ERR(bl)) {
 		dev_err(&pdev->dev, "failed to register backlight\n");
 		ret = PTR_ERR(bl);
+		if (pb->legacy)
+			pwm_free(pb->pwm);
 		goto err_alloc;
 	}
 
@@ -320,6 +341,7 @@ static int pwm_backlight_probe(struct platform_device *pdev)
 	}
 
 	bl->props.brightness = data->dft_brightness;
+	bl->props.power = initial_blank;
 	backlight_update_status(bl);
 
 	platform_set_drvdata(pdev, bl);

drivers/video/backlight/tps65217_bl.c

@@ -320,10 +320,19 @@ static int tps65217_bl_probe(struct platform_device *pdev)
 	return 0;
 }
 
+#ifdef CONFIG_OF
+static const struct of_device_id tps65217_bl_of_match[] = {
+	{ .compatible = "ti,tps65217-bl", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, tps65217_bl_of_match);
+#endif
+
 static struct platform_driver tps65217_bl_driver = {
 	.probe		= tps65217_bl_probe,
 	.driver		= {
 		.name	= "tps65217-bl",
+		.of_match_table = of_match_ptr(tps65217_bl_of_match),
 	},
 };