From 812e7465a7decf3cca0b5f71977a25eecd9626a4 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Ville=20Syrj=C3=A4l=C3=A4?= Date: Wed, 6 Aug 2014 14:49:48 +0300 Subject: [PATCH] drm: Have the vblank counter account for the time between vblank irq disable and drm_vblank_off() MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit If the vblank irq has already been disabled (via the disable timer) when we call drm_vblank_off() sample the counter and timestamp one last time. This will make the sure that the user space visible counter will account for time between vblank irq disable and drm_vblank_off(). Reviewed-by: Matt Roper Reviewed-by: Daniel Vetter Signed-off-by: Ville Syrjälä Signed-off-by: Daniel Vetter --- drivers/gpu/drm/drm_irq.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index af965174b083..1f86f6c6ecc6 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -140,6 +140,19 @@ static void vblank_disable_and_save(struct drm_device *dev, int crtc) */ spin_lock_irqsave(&dev->vblank_time_lock, irqflags); + /* + * If the vblank interrupt was already disbled update the count + * and timestamp to maintain the appearance that the counter + * has been ticking all along until this time. This makes the + * count account for the entire time between drm_vblank_on() and + * drm_vblank_off(). + */ + if (!dev->vblank[crtc].enabled) { + drm_update_vblank_count(dev, crtc); + spin_unlock_irqrestore(&dev->vblank_time_lock, irqflags); + return; + } + dev->driver->disable_vblank(dev, crtc); dev->vblank[crtc].enabled = false; -- 2.20.1