drm/atomic: Print debug message on atomic check failure

Does what it says on the label, it's a little confusing debugging atomic
check failures otherwise.

Cc: Manasi Navare <manasi.d.navare@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180411234302.2896-2-lyude@redhat.com

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 7d25c42f22dbcf8d3efc8949b1db59999eda693e..0da8c5e134b2fb5502c0e92282c5fdfa0d68aecf 100644 (file)
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -1702,11 +1702,15 @@ int drm_atomic_check_only(struct drm_atomic_state *state)
                }
        }
 
-       if (config->funcs->atomic_check)
+       if (config->funcs->atomic_check) {
                ret = config->funcs->atomic_check(state->dev, state);
 
-       if (ret)
-               return ret;
+               if (ret) {
+                       DRM_DEBUG_ATOMIC("atomic driver check for %p failed: %d\n",
+                                        state, ret);
+                       return ret;
+               }
+       }
 
        if (!state->allow_modeset) {
                for_each_new_crtc_in_state(state, crtc, crtc_state, i) {