Unlike other compositors, we don't get a crtc disable from weston when the cable is unplugged. As such, when the cable is re-plugged the kernel doesn't detect an enable/mode change and initiates a simple plane update instead of a modeset.

This patch clears the mode when all planes are off.

Signed-off-by: Sean Paul seanpaul@chromium.org ---

Sorry for the wide distribution, I'm not 100% on whether this is the right place to fix this.

Is this expected behavior from weston? Once we have solid fill support, it seems reasonable that a crtc might be left on if no planes are active (for blanking the screen, etc). However, hotplug is currently borked, so I don't want to just leave it as-is if this should be handled in the kernel.

Suggestions welcome!

Sean

drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c b/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c index 63dcc39b5efd..e89e46a4014e 100644 --- a/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c +++ b/drivers/gpu/drm/msm/disp/mdp5/mdp5_crtc.c @@ -645,7 +645,7 @@ static int mdp5_crtc_atomic_check(struct drm_crtc *crtc,

/* bail out early if there aren't any planes */ if (!cnt) - return 0; + return drm_atomic_set_mode_for_crtc(state, NULL);

hw_cfg = mdp5_cfg_get_hw_config(mdp5_kms->cfg);