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

[Daniel Vetter]

On Wed, Nov 26, 2014 at 06:58:04PM -0500, Rob Clark wrote:
> 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>

I think the problem here really is just that legacy state (plane->fb/crtc)
and atomic state get out of sync. Leaving planes around while the crtc
goes down is already possible with ->disable_plane and overlays, drivers
should be able to cope with that.

Merged into my atomic fixes pile, thanks.
-Daniel

> ---
>  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
> 

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch