[PATCH v4 4/4] drm/i915/display: Error codes for async flip failures

[Arun R Murthy <arun.r.murthy@intel.com>]

For failures in async flip atomic check/commit path return user readable
error codes in struct drm_atomic_state.

Signed-off-by: Arun R Murthy <arun.r.murthy@intel.com>
---
 drivers/gpu/drm/i915/display/intel_display.c | 31 +++++++++++++++++++++-------
 1 file changed, 23 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index c1a3a95c65f0b66c24ddd64f47dfdc67bbde86c9..41b054764fdec37e4d9410fa7fbe62dbcbd3a11f 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -5935,6 +5935,7 @@ static int intel_async_flip_check_uapi(struct intel_atomic_state *state,
 	struct intel_plane_state *new_plane_state;
 	struct intel_plane *plane;
 	int i;
+	char *err_string;
 
 	if (!new_crtc_state->uapi.async_flip)
 		return 0;
@@ -5947,9 +5948,13 @@ static int intel_async_flip_check_uapi(struct intel_atomic_state *state,
 	}
 
 	if (intel_crtc_needs_modeset(new_crtc_state)) {
-		drm_dbg_kms(display->drm,
-			    "[CRTC:%d:%s] modeset required\n",
-			    crtc->base.base.id, crtc->base.name);
+		err_string = "requires full modeset";
+		drm_dbg_kms(display->drm, "[CRTC:%d:%s] %s\n",
+			    crtc->base.base.id, crtc->base.name,
+			    err_string);
+		drm_mode_atomic_add_error_msg(state->base.error_code,
+					      DRM_MODE_ATOMIC_CRTC_NEED_FULL_MODESET,
+					      err_string);
 		return -EINVAL;
 	}
 
@@ -6001,6 +6006,7 @@ static int intel_async_flip_check_hw(struct intel_atomic_state *state, struct in
 	const struct intel_plane_state *new_plane_state, *old_plane_state;
 	struct intel_plane *plane;
 	int i;
+	char *err_string;
 
 	old_crtc_state = intel_atomic_get_old_crtc_state(state, crtc);
 	new_crtc_state = intel_atomic_get_new_crtc_state(state, crtc);
@@ -6016,9 +6022,13 @@ static int intel_async_flip_check_hw(struct intel_atomic_state *state, struct in
 	}
 
 	if (intel_crtc_needs_modeset(new_crtc_state)) {
-		drm_dbg_kms(display->drm,
-			    "[CRTC:%d:%s] modeset required\n",
-			    crtc->base.base.id, crtc->base.name);
+		err_string = "requires full modeset";
+		drm_dbg_kms(display->drm, "[CRTC:%d:%s] %s\n",
+			    crtc->base.base.id, crtc->base.name,
+			    err_string);
+		drm_mode_atomic_add_error_msg(state->base.error_code,
+					      DRM_MODE_ATOMIC_CRTC_NEED_FULL_MODESET,
+					      err_string);
 		return -EINVAL;
 	}
 
@@ -6056,11 +6066,16 @@ static int intel_async_flip_check_hw(struct intel_atomic_state *state, struct in
 
 		if (!intel_plane_can_async_flip(plane, new_plane_state->hw.fb->format->format,
 						new_plane_state->hw.fb->modifier)) {
+			err_string = "modifier does not support async flip";
 			drm_dbg_kms(display->drm,
-				    "[PLANE:%d:%s] pixel format %p4cc / modifier 0x%llx does not support async flip\n",
+				    "[PLANE:%d:%s] pixel format %p4cc / 0x%llx %s\n",
 				    plane->base.base.id, plane->base.name,
 				    &new_plane_state->hw.fb->format->format,
-				    new_plane_state->hw.fb->modifier);
+				    new_plane_state->hw.fb->modifier,
+				    err_string);
+			drm_mode_atomic_add_error_msg(state->base.error_code,
+						      DRM_MODE_ATOMIC_ASYNC_MODIFIER_NOT_SUPP,
+						      err_string);
 			return -EINVAL;
 		}
 

-- 
2.25.1