drm/exynos: update crtc to plane safely

if old_crtc isn't same as encoder->crtc then it means that
user changed crtc id to another one so a plane to old_crtc
should be disabled so that current plane can be updated safely
and plane->crtc should be set to new crtc(encoder->crtc)

Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>

1 files changed, 56 insertions, 3 deletions

diff --git a/drivers/gpu/drm/exynos/exynos_drm_encoder.c b/drivers/gpu/drm/exynos/exynos_drm_encoder.c
index f4531167fda6..92f9acf77b7f 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_encoder.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_encoder.c
@@ -45,6 +45,7 @@
  * @dpms: store the encoder dpms value.
  */
 struct exynos_drm_encoder {
+        struct drm_crtc                 *old_crtc;
         struct drm_encoder              drm_encoder;
         struct exynos_drm_manager       *manager;
         int dpms;
@@ -124,22 +125,74 @@ exynos_drm_encoder_mode_fixup(struct drm_encoder *encoder,
         return true;
 }
 
+static void disable_plane_to_crtc(struct drm_device *dev,
+                                                struct drm_crtc *old_crtc,
+                                                struct drm_crtc *new_crtc)
+{
+        struct drm_plane *plane;
+
+        /*
+         * if old_crtc isn't same as encoder->crtc then it means that
+         * user changed crtc id to another one so the plane to old_crtc
+         * should be disabled and plane->crtc should be set to new_crtc
+         * (encoder->crtc)
+         */
+        list_for_each_entry(plane, &dev->mode_config.plane_list, head) {
+                if (plane->crtc == old_crtc) {
+                        /*
+                         * do not change below call order.
+                         *
+                         * plane->funcs->disable_plane call checks
+                         * if encoder->crtc is same as plane->crtc and if same
+                         * then overlay_ops->disable callback will be called
+                         * to diasble current hw overlay so plane->crtc should
+                         * have new_crtc because new_crtc was set to
+                         * encoder->crtc in advance.
+                         */
+                        plane->crtc = new_crtc;
+                        plane->funcs->disable_plane(plane);
+                }
+        }
+}
+
 static void exynos_drm_encoder_mode_set(struct drm_encoder *encoder,
                                          struct drm_display_mode *mode,
                                          struct drm_display_mode *adjusted_mode)
 {
         struct drm_device *dev = encoder->dev;
         struct drm_connector *connector;
-        struct exynos_drm_manager *manager = exynos_drm_get_manager(encoder);
-        struct exynos_drm_manager_ops *manager_ops = manager->ops;
+        struct exynos_drm_manager *manager;
+        struct exynos_drm_manager_ops *manager_ops;
 
         DRM_DEBUG_KMS("%s\n", __FILE__);
 
         list_for_each_entry(connector, &dev->mode_config.connector_list, head) {
-                if (connector->encoder == encoder)
+                if (connector->encoder == encoder) {
+                        struct exynos_drm_encoder *exynos_encoder;
+
+                        exynos_encoder = to_exynos_encoder(encoder);
+
+                        if (exynos_encoder->old_crtc != encoder->crtc &&
+                                        exynos_encoder->old_crtc) {
+
+                                /*
+                                 * disable a plane to old crtc and change
+                                 * crtc of the plane to new one.
+                                 */
+                                disable_plane_to_crtc(dev,
+                                                exynos_encoder->old_crtc,
+                                                encoder->crtc);
+                        }
+
+                        manager = exynos_drm_get_manager(encoder);
+                        manager_ops = manager->ops;
+
                         if (manager_ops && manager_ops->mode_set)
                                 manager_ops->mode_set(manager->dev,
                                                         adjusted_mode);
+
+                        exynos_encoder->old_crtc = encoder->crtc;
+                }
         }
 }