Re: [PATCH v2 02/18] drm/exynos: use wait_event_timeout() for safety usage
From: Daniel Kurtz <hidden>
Date: 2014-05-21 06:01:12
Also in:
dri-devel, linux-samsung-soc
On Wed, May 21, 2014 at 12:42 PM, YoungJun Cho [off-list ref] wrote:
quoted hunk ↗ jump to hunk
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. And clears exynos_crtc->pending_flip in exynos_drm_crtc_page_flip() when exynos_drm_crtc_mode_set_commit() is failed. Signed-off-by: YoungJun Cho <redacted> Acked-by: Inki Dae <inki.dae@samsung.com> Acked-by: Kyungmin Park <kyungmin.park@samsung.com> --- drivers/gpu/drm/exynos/exynos_drm_crtc.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)diff --git a/drivers/gpu/drm/exynos/exynos_drm_crtc.c b/drivers/gpu/drm/exynos/exynos_drm_crtc.c index 95c9435..3bf091d 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_crtc.c +++ b/drivers/gpu/drm/exynos/exynos_drm_crtc.c@@ -69,8 +69,10 @@ 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); + if (!wait_event_timeout(exynos_crtc->pending_flip_queue, + !atomic_read(&exynos_crtc->pending_flip), + HZ/20)) + atomic_set(&exynos_crtc->pending_flip, 0);
I meant that changing this to wait_event_timeout() seems to be masking the original problem, that pending_flip wasn't being cleared. Now that you are now clearing pending_flip in the error path, you don't need the timeout, right? -Dan
quoted hunk ↗ jump to hunk
drm_vblank_off(crtc->dev, exynos_crtc->pipe); }@@ -259,6 +261,7 @@ static int exynos_drm_crtc_page_flip(struct drm_crtc *crtc, spin_lock_irq(&dev->event_lock); drm_vblank_put(dev, exynos_crtc->pipe); list_del(&event->base.link); + atomic_set(&exynos_crtc->pending_flip, 0); spin_unlock_irq(&dev->event_lock); goto out; --1.7.9.5