diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index 6f16a104d6d0d8cc6b35aa830ffa6f136fb558dc..e64d24951fc2a8fd5df44d32aec67b2464562792 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -1009,6 +1009,50 @@ void drm_crtc_vblank_put(struct drm_crtc *crtc) } EXPORT_SYMBOL(drm_crtc_vblank_put); +/** + * drm_wait_one_vblank - wait for one vblank + * @dev: DRM device + * @crtc: crtc index + * + * This waits for one vblank to pass on @crtc, using the irq driver interfaces. + * It is a failure to call this when the vblank irq for @crtc is disabled, e.g. + * due to lack of driver support or because the crtc is off. + */ +void drm_wait_one_vblank(struct drm_device *dev, int crtc) +{ + int ret; + u32 last; + + ret = drm_vblank_get(dev, crtc); + if (WARN_ON(ret)) + return; + + last = drm_vblank_count(dev, crtc); + + ret = wait_event_timeout(dev->vblank[crtc].queue, + last != drm_vblank_count(dev, crtc), + msecs_to_jiffies(100)); + + WARN_ON(ret == 0); + + drm_vblank_put(dev, crtc); +} +EXPORT_SYMBOL(drm_wait_one_vblank); + +/** + * drm_crtc_wait_one_vblank - wait for one vblank + * @crtc: DRM crtc + * + * This waits for one vblank to pass on @crtc, using the irq driver interfaces. + * It is a failure to call this when the vblank irq for @crtc is disabled, e.g. + * due to lack of driver support or because the crtc is off. + */ +void drm_crtc_wait_one_vblank(struct drm_crtc *crtc) +{ + drm_wait_one_vblank(crtc->dev, drm_crtc_index(crtc)); +} +EXPORT_SYMBOL(drm_crtc_wait_one_vblank); + /** * drm_vblank_off - disable vblank events on a CRTC * @dev: DRM device diff --git a/include/drm/drmP.h b/include/drm/drmP.h index d3d9be6b83efe13a0aa1425656f83c46429b4e46..c2209178981f9bfe40c0e4b4f725a03677695567 100644 --- a/include/drm/drmP.h +++ b/include/drm/drmP.h @@ -1327,6 +1327,8 @@ extern int drm_vblank_get(struct drm_device *dev, int crtc); extern void drm_vblank_put(struct drm_device *dev, int crtc); extern int drm_crtc_vblank_get(struct drm_crtc *crtc); extern void drm_crtc_vblank_put(struct drm_crtc *crtc); +extern void drm_wait_one_vblank(struct drm_device *dev, int crtc); +extern void drm_crtc_wait_one_vblank(struct drm_crtc *crtc); extern void drm_vblank_off(struct drm_device *dev, int crtc); extern void drm_vblank_on(struct drm_device *dev, int crtc); extern void drm_crtc_vblank_off(struct drm_crtc *crtc);