[1/4] drm/panel: seperate panel power control from panel prepare/unprepare

diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c
index 0ddc37551194..a19c96e710fc 100644
--- a/drivers/gpu/drm/bridge/panel.c
+++ b/drivers/gpu/drm/bridge/panel.c
@@ -125,6 +125,23 @@  static int panel_bridge_get_modes(struct drm_bridge *bridge,
 	return drm_panel_get_modes(panel_bridge->panel, connector);
 }
 
+int panel_bridge_prepare_power(struct drm_bridge *bridge)
+{
+	struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
+
+	return drm_panel_prepare_power(panel_bridge->panel);
+}
+EXPORT_SYMBOL(panel_bridge_prepare_power);
+
+int panel_bridge_unprepare_power(struct drm_bridge *bridge)
+{
+        struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge);
+
+        return drm_panel_unprepare_power(panel_bridge->panel);
+}
+EXPORT_SYMBOL(panel_bridge_unprepare_power);
+
+
 static const struct drm_bridge_funcs panel_bridge_bridge_funcs = {
 	.attach = panel_bridge_attach,
 	.detach = panel_bridge_detach,
diff --git a/drivers/gpu/drm/drm_panel.c b/drivers/gpu/drm/drm_panel.c
index f634371c717a..7bb5185db17d 100644
--- a/drivers/gpu/drm/drm_panel.c
+++ b/drivers/gpu/drm/drm_panel.c
@@ -115,6 +115,24 @@  int drm_panel_prepare(struct drm_panel *panel)
 }
 EXPORT_SYMBOL(drm_panel_prepare);
 
+/**
+ * drm_panel_prepare_power - power on a panel's power
+ * @panel: DRM panel
+ *
+ * Calling this function will enable power and deassert any reset signals to
+ * the panel.
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int drm_panel_prepare_power(struct drm_panel *panel)
+{
+	if (panel && panel->funcs && panel->funcs->prepare_power)
+		return panel->funcs->prepare_power(panel);
+
+	return panel ? -ENOSYS : -EINVAL;
+}
+EXPORT_SYMBOL(drm_panel_prepare_power);
+
 /**
  * drm_panel_unprepare - power off a panel
  * @panel: DRM panel
@@ -138,6 +156,26 @@  int drm_panel_unprepare(struct drm_panel *panel)
 }
 EXPORT_SYMBOL(drm_panel_unprepare);
 
+/**
+ * drm_panel_unprepare_power - power off a panel
+ * @panel: DRM panel
+ *
+ * Calling this function will completely power off a panel (assert the panel's
+ * reset, turn off power supplies, ...). After this function has completed, it
+ * is usually no longer possible to communicate with the panel until another
+ * call to drm_panel_prepare_power and drm_panel_prepare().
+ *
+ * Return: 0 on success or a negative error code on failure.
+ */
+int drm_panel_unprepare_power(struct drm_panel *panel)
+{
+	if (panel && panel->funcs && panel->funcs->unprepare_power)
+		return panel->funcs->unprepare_power(panel);
+
+	return panel ? -ENOSYS : -EINVAL;
+}
+EXPORT_SYMBOL(drm_panel_unprepare_power);
+
 /**
  * drm_panel_enable - enable a panel
  * @panel: DRM panel
diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
index 2195daa289d2..cc94c9da47d8 100644
--- a/include/drm/drm_bridge.h
+++ b/include/drm/drm_bridge.h
@@ -892,6 +892,8 @@  struct drm_bridge *devm_drm_panel_bridge_add_typed(struct device *dev,
 						   struct drm_panel *panel,
 						   u32 connector_type);
 struct drm_connector *drm_panel_bridge_connector(struct drm_bridge *bridge);
+int panel_bridge_prepare_power(struct drm_bridge *bridge);
+int panel_bridge_unprepare_power(struct drm_bridge *bridge);
 #endif
 
 #endif
diff --git a/include/drm/drm_panel.h b/include/drm/drm_panel.h
index 33605c3f0eba..48e83712ad44 100644
--- a/include/drm/drm_panel.h
+++ b/include/drm/drm_panel.h
@@ -68,6 +68,13 @@  enum drm_panel_orientation;
  * functionality to enable/disable backlight.
  */
 struct drm_panel_funcs {
+	/**
+	 * @prepare_power:
+	 *
+	 * Turn on panel power.
+	 */
+	int (*prepare_power)(struct drm_panel *panel);
+
 	/**
 	 * @prepare:
 	 *
@@ -115,6 +122,13 @@  struct drm_panel_funcs {
 	int (*get_modes)(struct drm_panel *panel,
 			 struct drm_connector *connector);
 
+	/**
+	 * @unprepare_power:
+	 *
+	 * Turn off panel_power.
+	 */
+	int (*unprepare_power)(struct drm_panel *panel);
+
 	/**
 	 * @get_timings:
 	 *
@@ -180,6 +194,9 @@  void drm_panel_init(struct drm_panel *panel, struct device *dev,
 void drm_panel_add(struct drm_panel *panel);
 void drm_panel_remove(struct drm_panel *panel);
 
+int drm_panel_prepare_power(struct drm_panel *panel);
+int drm_panel_unprepare_power(struct drm_panel *panel);
+
 int drm_panel_prepare(struct drm_panel *panel);
 int drm_panel_unprepare(struct drm_panel *panel);