1 files changed, 22 insertions, 18 deletions

diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index f554516ec2a4..738a4294d820 100644
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -565,14 +565,13 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
 
         DRM_DEBUG_KMS("\n");
 
-        if (!set)
-                return -EINVAL;
+        BUG_ON(!set);
+        BUG_ON(!set->crtc);
+        BUG_ON(!set->crtc->helper_private);
 
-        if (!set->crtc)
-                return -EINVAL;
-
-        if (!set->crtc->helper_private)
-                return -EINVAL;
+        /* Enforce sane interface api - has been abused by the fb helper. */
+        BUG_ON(!set->mode && set->fb);
+        BUG_ON(set->fb && set->num_connectors == 0);
 
         crtc_funcs = set->crtc->helper_private;
 
@@ -646,11 +645,6 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
                         mode_changed = true;
                 } else if (set->fb == NULL) {
                         mode_changed = true;
-                } else if (set->fb->depth != set->crtc->fb->depth) {
-                        mode_changed = true;
-                } else if (set->fb->bits_per_pixel !=
-                           set->crtc->fb->bits_per_pixel) {
-                        mode_changed = true;
                 } else if (set->fb->pixel_format !=
                            set->crtc->fb->pixel_format) {
                         mode_changed = true;
@@ -760,12 +754,6 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
                                 ret = -EINVAL;
                                 goto fail;
                         }
-                        DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
-                        for (i = 0; i < set->num_connectors; i++) {
-                                DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
-                                              drm_get_connector_name(set->connectors[i]));
-                                set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
-                        }
                 }
                 drm_helper_disable_unused_functions(dev);
         } else if (fb_changed) {
@@ -783,6 +771,22 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
                 }
         }
 
+        /*
+         * crtc set_config helpers implicit set the crtc and all connected
+         * encoders to DPMS on for a full mode set. But for just an fb update it
+         * doesn't do that. To not confuse userspace, do an explicit DPMS_ON
+         * unconditionally. This will also ensure driver internal dpms state is
+         * consistent again.
+         */
+        if (set->crtc->enabled) {
+                DRM_DEBUG_KMS("Setting connector DPMS state to on\n");
+                for (i = 0; i < set->num_connectors; i++) {
+                        DRM_DEBUG_KMS("\t[CONNECTOR:%d:%s] set DPMS on\n", set->connectors[i]->base.id,
+                                      drm_get_connector_name(set->connectors[i]));
+                        set->connectors[i]->funcs->dpms(set->connectors[i], DRM_MODE_DPMS_ON);
+                }
+        }
+
         kfree(save_connectors);
         kfree(save_encoders);
         kfree(save_crtcs);