drm/atomic-helper: Check encoder/crtc constraints

This was totally lost when I originally created the atomic helpers.

We probably should also check possible_clones in the helpers, but
since the legacy ones didn't do that this is for a separate patch.

Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Daniel Stone <daniels@collabora.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Tested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1447868808-10266-1-git-send-email-daniel.vetter@ffwll.ch

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index cd398a245d2e..e5aec45bf985 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -210,6 +210,14 @@ update_connector_routing(struct drm_atomic_state *state, int conn_idx)
                 return -EINVAL;
         }
 
+        if (!drm_encoder_crtc_ok(new_encoder, connector_state->crtc)) {
+                DRM_DEBUG_ATOMIC("[ENCODER:%d:%s] incompatible with [CRTC:%d]\n",
+                                 new_encoder->base.id,
+                                 new_encoder->name,
+                                 connector_state->crtc->base.id);
+                return -EINVAL;
+        }
+
         if (new_encoder == connector_state->best_encoder) {
                 DRM_DEBUG_ATOMIC("[CONNECTOR:%d:%s] keeps [ENCODER:%d:%s], now on [CRTC:%d]\n",
                                  connector->base.id,