[RFC v2 PATCH 03/14] drm/exynos: use wait_event_timeout() for safety usage

YoungJun Cho
2014-04-21T12:28:30Z

There could be the case that the page flip operation isn't finished correctly
with some abnormal condition such as panel reset. So this patch replaces
wait_event() with wait_event_timeout() to avoid waiting for page flip completion
infinitely.

Signed-off-by: YoungJun Cho <yj44.cho-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
Acked-by: Inki Dae <inki.dae-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
Acked-by: Kyungmin Park <kyungmin.park-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
---
drivers/gpu/drm/exynos/exynos_drm_crtc.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/exynos/exynos_drm_crtc.c b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
index e930d4f..1419d11 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_crtc.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_crtc.c
@@ -69,8 +69,9 @@ static void exynos_drm_crtc_dpms(struct drm_crtc *crtc, int mode)

if (mode > DRM_MODE_DPMS_ON) {
/* wait for the completion of page flip. */
- wait_event(exynos_crtc->pending_flip_queue,
- atomic_read(&exynos_crtc->pending_flip) == 0);
+ wait_event_timeout(exynos_crtc->pending_flip_queue,
+ !atomic_read(&exynos_crtc->pending_flip),
+ HZ/20);
drm_vblank_off(crtc->dev, exynos_crtc->pipe);
}

--
1.7.9.5

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