diff --git a/Documentation/gpu/todo.rst b/Documentation/gpu/todo.rst
index 68bdafa0284f..e3b272c97758 100644
--- a/Documentation/gpu/todo.rst
+++ b/Documentation/gpu/todo.rst
@@ -452,6 +452,30 @@ Contact: Thomas Zimmermann <tzimmermann@suse.de>
 
 Level: Starter
 
+Clean up checks for already prepared/enabled in panels
+------------------------------------------------------
+
+In a whole pile of panel drivers, we have code to make the
+prepare/unprepare/enable/disable callbacks behave as no-ops if they've already
+been called. To get some idea of the duplicated code, try:
+  git grep 'if.*>prepared' -- drivers/gpu/drm/panel
+  git grep 'if.*>enabled' -- drivers/gpu/drm/panel
+
+In the patch ("drm/panel: Check for already prepared/enabled in drm_panel")
+we've moved this check to the core. Now we can most definitely remove the
+check from the individual panels and save a pile of code.
+
+In adition to removing the check from the individual panels, it is believed
+that even the core shouldn't need this check and that should be considered
+an error if other code ever relies on this check. The check in the core
+currently prints a warning whenever something is relying on this check with
+dev_warn(). After a little while, we likely want to promote this to a
+WARN(1) to help encourage folks not to rely on this behavior.
+
+Contact: Douglas Anderson <dianders@chromium.org>
+
+Level: Starter/Intermediate
+
 
 Core refactorings
 =================
diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
index f634371c717a..4e1c4e42575b 100644
--- a/drivers/gpu/drm/drm_panel.c
+++ b/drivers/gpu/drm/drm_panel.c
@@ -105,11 +105,22 @@ EXPORT_SYMBOL(drm_panel_remove);
  */
 int drm_panel_prepare(struct drm_panel *panel)
 {
+	int ret;
+
 	if (!panel)
 		return -EINVAL;
 
-	if (panel->funcs && panel->funcs->prepare)
-		return panel->funcs->prepare(panel);
+	if (panel->prepared) {
+		dev_warn(panel->dev, "Skipping prepare of already prepared panel\n");
+		return 0;
+	}
+
+	if (panel->funcs && panel->funcs->prepare) {
+		ret = panel->funcs->prepare(panel);
+		if (ret < 0)
+			return ret;
+	}
+	panel->prepared = true;
 
 	return 0;
 }
@@ -128,11 +139,22 @@ EXPORT_SYMBOL(drm_panel_prepare);
  */
 int drm_panel_unprepare(struct drm_panel *panel)
 {
+	int ret;
+
 	if (!panel)
 		return -EINVAL;
 
-	if (panel->funcs && panel->funcs->unprepare)
-		return panel->funcs->unprepare(panel);
+	if (!panel->prepared) {
+		dev_warn(panel->dev, "Skipping unprepare of already unprepared panel\n");
+		return 0;
+	}
+
+	if (panel->funcs && panel->funcs->unprepare) {
+		ret = panel->funcs->unprepare(panel);
+		if (ret < 0)
+			return ret;
+	}
+	panel->prepared = false;
 
 	return 0;
 }
@@ -155,11 +177,17 @@ int drm_panel_enable(struct drm_panel *panel)
 	if (!panel)
 		return -EINVAL;
 
+	if (panel->enabled) {
+		dev_warn(panel->dev, "Skipping enable of already enabled panel\n");
+		return 0;
+	}
+
 	if (panel->funcs && panel->funcs->enable) {
 		ret = panel->funcs->enable(panel);
 		if (ret < 0)
 			return ret;
 	}
+	panel->enabled = true;
 
 	ret = backlight_enable(panel->backlight);
 	if (ret < 0)
@@ -187,13 +215,22 @@ int drm_panel_disable(struct drm_panel *panel)
 	if (!panel)
 		return -EINVAL;
 
+	if (!panel->enabled) {
+		dev_warn(panel->dev, "Skipping disable of already disabled panel\n");
+		return 0;
+	}
+
 	ret = backlight_disable(panel->backlight);
 	if (ret < 0)
 		DRM_DEV_INFO(panel->dev, "failed to disable backlight: %d\n",
 			     ret);
 
-	if (panel->funcs && panel->funcs->disable)
-		return panel->funcs->disable(panel);
+	if (panel->funcs && panel->funcs->disable) {
+		ret = panel->funcs->disable(panel);
+		if (ret < 0)
+			return ret;
+	}
+	panel->enabled = false;
 
 	return 0;
 }
diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
index 432fab2347eb..c6cf75909389 100644
--- a/include/drm/drm_panel.h
+++ b/include/drm/drm_panel.h
@@ -198,6 +198,20 @@ struct drm_panel {
 	 * the panel is powered up.
 	 */
 	bool prepare_prev_first;
+
+	/**
+	 * @prepared:
+	 *
+	 * If true then the panel has been prepared.
+	 */
+	bool prepared;
+
+	/**
+	 * @enabled:
+	 *
+	 * If true then the panel has been enabled.
+	 */
+	bool enabled;
 };
 
 void drm_panel_init(struct drm_panel *panel, struct device *dev,
