[PATCH] drm/atomic: clear plane's CRTC and FB when shutting down

[Rob Clark]

Otherwise we'd still end up w/ the plane attached to the CRTC, and
seemingly active, but without an FB.  Which ends up going *boom*
in the drivers.

Slightly modified version of Daniel's irc suggestion.

CC: Daniel Vetter <daniel at ffwll.ch>
Signed-off-by: Rob Clark <robdclark at gmail.com>
---
 drivers/gpu/drm/drm_atomic_helper.c | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index a348688..7d5e6c1 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1409,11 +1409,24 @@ retry:
 		goto fail;
 	}
 
+	primary_state = drm_atomic_get_plane_state(state, crtc->primary);
+	if (IS_ERR(primary_state)) {
+		ret = PTR_ERR(primary_state);
+		goto fail;
+	}
+
 	if (!set->mode) {
 		WARN_ON(set->fb);
 		WARN_ON(set->num_connectors);
 
 		crtc_state->enable = false;
+
+		ret = drm_atomic_set_crtc_for_plane(state, crtc->primary, NULL);
+		if (ret != 0)
+			goto fail;
+
+		drm_atomic_set_fb_for_plane(primary_state, NULL);
+
 		goto commit;
 	}
 
@@ -1423,12 +1436,6 @@ retry:
 	crtc_state->enable = true;
 	drm_mode_copy(&crtc_state->mode, set->mode);
 
-	primary_state = drm_atomic_get_plane_state(state, crtc->primary);
-	if (IS_ERR(primary_state)) {
-		ret = PTR_ERR(primary_state);
-		goto fail;
-	}
-
 	ret = drm_atomic_set_crtc_for_plane(state, crtc->primary, crtc);
 	if (ret != 0)
 		goto fail;
-- 
1.9.3