1 files changed, 33 insertions, 15 deletions

diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index e490e69db21e..964c5eb1fada 100644
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -480,6 +480,7 @@ bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
         int saved_x, saved_y;
         struct drm_encoder *encoder;
         bool ret = true;
+        bool depth_changed, bpp_changed;
 
         adjusted_mode = drm_mode_duplicate(dev, mode);
 
@@ -488,6 +489,15 @@ bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
         if (!crtc->enabled)
                 return true;
 
+        if (old_fb && crtc->fb) {
+                depth_changed = (old_fb->depth != crtc->fb->depth);
+                bpp_changed = (old_fb->bits_per_pixel !=
+                               crtc->fb->bits_per_pixel);
+        } else {
+                depth_changed = true;
+                bpp_changed = true;
+        }
+
         saved_mode = crtc->mode;
         saved_x = crtc->x;
         saved_y = crtc->y;
@@ -500,7 +510,8 @@ bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
         crtc->y = y;
 
         if (drm_mode_equal(&saved_mode, &crtc->mode)) {
-                if (saved_x != crtc->x || saved_y != crtc->y) {
+                if (saved_x != crtc->x || saved_y != crtc->y ||
+                    depth_changed || bpp_changed) {
                         crtc_funcs->mode_set_base(crtc, crtc->x, crtc->y,
                                                   old_fb);
                         goto done;
@@ -606,8 +617,8 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
         struct drm_encoder **save_encoders, *new_encoder;
         struct drm_framebuffer *old_fb;
         bool save_enabled;
-        bool changed = false;
-        bool flip_or_move = false;
+        bool mode_changed = false;
+        bool fb_changed = false;
         struct drm_connector *connector;
         int count = 0, ro, fail = 0;
         struct drm_crtc_helper_funcs *crtc_funcs;
@@ -635,7 +646,10 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
         /* save previous config */
         save_enabled = set->crtc->enabled;
 
-        /* this is meant to be num_connector not num_crtc */
+        /*
+         * We do mode_config.num_connectors here since we'll look at the
+         * CRTC and encoder associated with each connector later.
+         */
         save_crtcs = kzalloc(dev->mode_config.num_connector *
                              sizeof(struct drm_crtc *), GFP_KERNEL);
         if (!save_crtcs)
@@ -651,21 +665,25 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
         /* We should be able to check here if the fb has the same properties
          * and then just flip_or_move it */
         if (set->crtc->fb != set->fb) {
-                /* if we have no fb then its a change not a flip */
+                /* If we have no fb then treat it as a full mode set */
                 if (set->crtc->fb == NULL)
-                        changed = true;
+                        mode_changed = true;
+                else if ((set->fb->bits_per_pixel !=
+                         set->crtc->fb->bits_per_pixel) ||
+                         set->fb->depth != set->crtc->fb->depth)
+                        fb_changed = true;
                 else
-                        flip_or_move = true;
+                        fb_changed = true;
         }
 
         if (set->x != set->crtc->x || set->y != set->crtc->y)
-                flip_or_move = true;
+                fb_changed = true;
 
         if (set->mode && !drm_mode_equal(set->mode, &set->crtc->mode)) {
                 DRM_DEBUG("modes are different\n");
                 drm_mode_debug_printmodeline(&set->crtc->mode);
                 drm_mode_debug_printmodeline(set->mode);
-                changed = true;
+                mode_changed = true;
         }
 
         /* a) traverse passed in connector list and get encoders for them */
@@ -688,7 +706,7 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
                 }
 
                 if (new_encoder != connector->encoder) {
-                        changed = true;
+                        mode_changed = true;
                         connector->encoder = new_encoder;
                 }
         }
@@ -715,16 +733,16 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
                                 new_crtc = set->crtc;
                 }
                 if (new_crtc != connector->encoder->crtc) {
-                        changed = true;
+                        mode_changed = true;
                         connector->encoder->crtc = new_crtc;
                 }
         }
 
         /* mode_set_base is not a required function */
-        if (flip_or_move && !crtc_funcs->mode_set_base)
-                changed = true;
+        if (fb_changed && !crtc_funcs->mode_set_base)
+                mode_changed = true;
 
-        if (changed) {
+        if (mode_changed) {
                 old_fb = set->crtc->fb;
                 set->crtc->fb = set->fb;
                 set->crtc->enabled = (set->mode != NULL);
@@ -743,7 +761,7 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
                         set->crtc->desired_mode = set->mode;
                 }
                 drm_helper_disable_unused_functions(dev);
-        } else if (flip_or_move) {
+        } else if (fb_changed) {
                 old_fb = set->crtc->fb;
                 if (set->crtc->fb != set->fb)
                         set->crtc->fb = set->fb;