diff options
Diffstat (limited to 'drivers/gpu/drm/drm_vblank.c')
| -rw-r--r-- | drivers/gpu/drm/drm_vblank.c | 31 |
1 files changed, 23 insertions, 8 deletions
diff --git a/drivers/gpu/drm/drm_vblank.c b/drivers/gpu/drm/drm_vblank.c index c781cb426bf1..28cdcf76b6f9 100644 --- a/drivers/gpu/drm/drm_vblank.c +++ b/drivers/gpu/drm/drm_vblank.c @@ -120,6 +120,9 @@ static u32 __get_vblank_counter(struct drm_device *dev, unsigned int pipe) if (drm_core_check_feature(dev, DRIVER_MODESET)) { struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); + if (WARN_ON(!crtc)) + return 0; + if (crtc->funcs->get_vblank_counter) return crtc->funcs->get_vblank_counter(crtc); } @@ -318,6 +321,9 @@ static void __disable_vblank(struct drm_device *dev, unsigned int pipe) if (drm_core_check_feature(dev, DRIVER_MODESET)) { struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); + if (WARN_ON(!crtc)) + return; + if (crtc->funcs->disable_vblank) { crtc->funcs->disable_vblank(crtc); return; @@ -920,6 +926,9 @@ static int __enable_vblank(struct drm_device *dev, unsigned int pipe) if (drm_core_check_feature(dev, DRIVER_MODESET)) { struct drm_crtc *crtc = drm_crtc_from_index(dev, pipe); + if (WARN_ON(!crtc)) + return 0; + if (crtc->funcs->enable_vblank) return crtc->funcs->enable_vblank(crtc); } @@ -1238,12 +1247,15 @@ void drm_crtc_vblank_on(struct drm_crtc *crtc) EXPORT_SYMBOL(drm_crtc_vblank_on); /** - * drm_vblank_restore - estimated vblanks using timestamps and update it. + * drm_vblank_restore - estimate missed vblanks and update vblank count. + * @dev: DRM device + * @pipe: CRTC index * * Power manamement features can cause frame counter resets between vblank - * disable and enable. Drivers can then use this function in their - * &drm_crtc_funcs.enable_vblank implementation to estimate the vblanks since - * the last &drm_crtc_funcs.disable_vblank. + * disable and enable. Drivers can use this function in their + * &drm_crtc_funcs.enable_vblank implementation to estimate missed vblanks since + * the last &drm_crtc_funcs.disable_vblank using timestamps and update the + * vblank counter. * * This function is the legacy version of drm_crtc_vblank_restore(). */ @@ -1284,11 +1296,14 @@ void drm_vblank_restore(struct drm_device *dev, unsigned int pipe) EXPORT_SYMBOL(drm_vblank_restore); /** - * drm_crtc_vblank_restore - estimate vblanks using timestamps and update it. + * drm_crtc_vblank_restore - estimate missed vblanks and update vblank count. + * @crtc: CRTC in question + * * Power manamement features can cause frame counter resets between vblank - * disable and enable. Drivers can then use this function in their - * &drm_crtc_funcs.enable_vblank implementation to estimate the vblanks since - * the last &drm_crtc_funcs.disable_vblank. + * disable and enable. Drivers can use this function in their + * &drm_crtc_funcs.enable_vblank implementation to estimate missed vblanks since + * the last &drm_crtc_funcs.disable_vblank using timestamps and update the + * vblank counter. */ void drm_crtc_vblank_restore(struct drm_crtc *crtc) { |