[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