1 files changed, 53 insertions, 24 deletions

diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c
index 77c5cb2a44e2..3267acf8dc5b 100644
--- a/drivers/video/backlight/lcd.c
+++ b/drivers/video/backlight/lcd.c
@@ -20,6 +20,24 @@
 
 #if defined(CONFIG_FB) || (defined(CONFIG_FB_MODULE) && \
 			   defined(CONFIG_LCD_CLASS_DEVICE_MODULE))
+static int to_lcd_power(int fb_blank)
+{
+	switch (fb_blank) {
+	case FB_BLANK_UNBLANK:
+		return LCD_POWER_ON;
+	/* deprecated; TODO: should become 'off' */
+	case FB_BLANK_NORMAL:
+		return LCD_POWER_REDUCED;
+	case FB_BLANK_VSYNC_SUSPEND:
+		return LCD_POWER_REDUCED_VSYNC_SUSPEND;
+	/* 'off' */
+	case FB_BLANK_HSYNC_SUSPEND:
+	case FB_BLANK_POWERDOWN:
+	default:
+		return LCD_POWER_OFF;
+	}
+}
+
 /* This callback gets called when something important happens inside a
  * framebuffer driver. We're looking if that important event is blanking,
  * and if it is, we're switching lcd power as well ...
@@ -27,24 +45,32 @@
 static int fb_notifier_callback(struct notifier_block *self,
 				 unsigned long event, void *data)
 {
-	struct lcd_device *ld;
+	struct lcd_device *ld = container_of(self, struct lcd_device, fb_notif);
 	struct fb_event *evdata = data;
+	struct fb_info *info = evdata->info;
+	struct lcd_device *fb_lcd = fb_lcd_device(info);
+
+	guard(mutex)(&ld->ops_lock);
 
-	ld = container_of(self, struct lcd_device, fb_notif);
 	if (!ld->ops)
 		return 0;
+	if (ld->ops->controls_device && !ld->ops->controls_device(ld, info->device))
+		return 0;
+	if (fb_lcd && fb_lcd != ld)
+		return 0;
 
-	mutex_lock(&ld->ops_lock);
-	if (!ld->ops->check_fb || ld->ops->check_fb(ld, evdata->info)) {
-		if (event == FB_EVENT_BLANK) {
-			if (ld->ops->set_power)
-				ld->ops->set_power(ld, *(int *)evdata->data);
-		} else {
-			if (ld->ops->set_mode)
-				ld->ops->set_mode(ld, evdata->data);
-		}
+	if (event == FB_EVENT_BLANK) {
+		int power = to_lcd_power(*(int *)evdata->data);
+
+		if (ld->ops->set_power)
+			ld->ops->set_power(ld, power);
+	} else {
+		const struct fb_videomode *videomode = evdata->data;
+
+		if (ld->ops->set_mode)
+			ld->ops->set_mode(ld, videomode->xres, videomode->yres);
 	}
-	mutex_unlock(&ld->ops_lock);
+
 	return 0;
 }
 
@@ -159,8 +185,6 @@ static ssize_t max_contrast_show(struct device *dev,
 }
 static DEVICE_ATTR_RO(max_contrast);
 
-static struct class *lcd_class;
-
 static void lcd_device_release(struct device *dev)
 {
 	struct lcd_device *ld = to_lcd_device(dev);
@@ -175,6 +199,11 @@ static struct attribute *lcd_device_attrs[] = {
 };
 ATTRIBUTE_GROUPS(lcd_device);
 
+static const struct class lcd_class = {
+	.name = "lcd",
+	.dev_groups = lcd_device_groups,
+};
+
 /**
  * lcd_device_register - register a new object of lcd_device class.
  * @name: the name of the new object(must be the same as the name of the
@@ -188,7 +217,7 @@ ATTRIBUTE_GROUPS(lcd_device);
  * or a pointer to the newly allocated device.
  */
 struct lcd_device *lcd_device_register(const char *name, struct device *parent,
-		void *devdata, struct lcd_ops *ops)
+		void *devdata, const struct lcd_ops *ops)
 {
 	struct lcd_device *new_ld;
 	int rc;
@@ -202,7 +231,7 @@ struct lcd_device *lcd_device_register(const char *name, struct device *parent,
 	mutex_init(&new_ld->ops_lock);
 	mutex_init(&new_ld->update_lock);
 
-	new_ld->dev.class = lcd_class;
+	new_ld->dev.class = &lcd_class;
 	new_ld->dev.parent = parent;
 	new_ld->dev.release = lcd_device_release;
 	dev_set_name(&new_ld->dev, "%s", name);
@@ -276,7 +305,7 @@ static int devm_lcd_device_match(struct device *dev, void *res, void *data)
  */
 struct lcd_device *devm_lcd_device_register(struct device *dev,
 		const char *name, struct device *parent,
-		void *devdata, struct lcd_ops *ops)
+		void *devdata, const struct lcd_ops *ops)
 {
 	struct lcd_device **ptr, *lcd;
 
@@ -318,19 +347,19 @@ EXPORT_SYMBOL(devm_lcd_device_unregister);
 
 static void __exit lcd_class_exit(void)
 {
-	class_destroy(lcd_class);
+	class_unregister(&lcd_class);
 }
 
 static int __init lcd_class_init(void)
 {
-	lcd_class = class_create("lcd");
-	if (IS_ERR(lcd_class)) {
-		pr_warn("Unable to create backlight class; errno = %ld\n",
-			PTR_ERR(lcd_class));
-		return PTR_ERR(lcd_class);
+	int ret;
+
+	ret = class_register(&lcd_class);
+	if (ret) {
+		pr_warn("Unable to create backlight class; errno = %d\n", ret);
+		return ret;
 	}
 
-	lcd_class->dev_groups = lcd_device_groups;
 	return 0;
 }