drm/panel: sharp-lq101r1sx01: use drm_panel backlight support

Use the backlight support in drm_panel to simplify the driver
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20191207140353.23967-21-sam@ravnborg.org

drivers/gpu/drm/panel/panel-sharp-lq101r1sx01.c

@@ -3,7 +3,6 @@
  * Copyright (C) 2014 NVIDIA Corporation
  */
 
-#include <linux/backlight.h>
 #include <linux/delay.h>
 #include <linux/gpio/consumer.h>
 #include <linux/module.h>
@@ -23,7 +22,6 @@ struct sharp_panel {
 	struct mipi_dsi_device *link1;
 	struct mipi_dsi_device *link2;
 
-	struct backlight_device *backlight;
 	struct regulator *supply;
 
 	bool prepared;
@@ -94,8 +92,6 @@ static int sharp_panel_disable(struct drm_panel *panel)
 	if (!sharp->enabled)
 		return 0;
 
-	backlight_disable(sharp->backlight);
-
 	sharp->enabled = false;
 
 	return 0;
@@ -258,8 +254,6 @@ static int sharp_panel_enable(struct drm_panel *panel)
 	if (sharp->enabled)
 		return 0;
 
-	backlight_enable(sharp->backlight);
-
 	sharp->enabled = true;
 
 	return 0;
@@ -317,7 +311,7 @@ MODULE_DEVICE_TABLE(of, sharp_of_match);
 
 static int sharp_panel_add(struct sharp_panel *sharp)
 {
-	struct device *dev = &sharp->link1->dev;
+	int ret;
 
 	sharp->mode = &default_mode;
 
@@ -325,14 +319,13 @@ static int sharp_panel_add(struct sharp_panel *sharp)
 	if (IS_ERR(sharp->supply))
 		return PTR_ERR(sharp->supply);
 
-	sharp->backlight = devm_of_find_backlight(dev);
-
-	if (IS_ERR(sharp->backlight))
-		return PTR_ERR(sharp->backlight);
-
 	drm_panel_init(&sharp->base, &sharp->link1->dev, &sharp_panel_funcs,
 		       DRM_MODE_CONNECTOR_DSI);
 
+	ret = drm_panel_of_backlight(&sharp->base);
+	if (ret)
+		return ret;
+
 	return drm_panel_add(&sharp->base);
 }
 
@@ -408,7 +401,7 @@ static int sharp_panel_remove(struct mipi_dsi_device *dsi)
 		return 0;
 	}
 
-	err = sharp_panel_disable(&sharp->base);
+	err = drm_panel_disable(&sharp->base);
 	if (err < 0)
 		dev_err(&dsi->dev, "failed to disable panel: %d\n", err);
 
@@ -429,7 +422,7 @@ static void sharp_panel_shutdown(struct mipi_dsi_device *dsi)
 	if (!sharp)
 		return;
 
-	sharp_panel_disable(&sharp->base);
+	drm_panel_disable(&sharp->base);
 }
 
 static struct mipi_dsi_driver sharp_panel_driver = {