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author | Daniel Vetter <daniel.vetter@ffwll.ch> | 2014-07-25 21:34:03 (GMT) |
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committer | Daniel Vetter <daniel.vetter@ffwll.ch> | 2014-08-11 12:25:21 (GMT) |
commit | e8450f51a4b39cfe0878b4aee339820b2bfff240 (patch) | |
tree | ee6cf4685f8524bf47cf49911d61ba21c77a5b33 /drivers/gpu/drm/drm_irq.c | |
parent | 2a0d7cfd9482ca4c10a4d8794791760a6a7ce40c (diff) | |
download | linux-e8450f51a4b39cfe0878b4aee339820b2bfff240.tar.xz |
drm/irq: Implement a generic vblank_wait function
As usual in both a crtc index and a struct drm_crtc * version.
The function assumes that no one drivers their display below 10Hz, and
it will complain if the vblank wait takes longer than that.
v2: Also check dev->max_vblank_counter since some drivers register a
fake get_vblank_counter function.
v3: Use drm_vblank_count instead of calling the low-level
->get_vblank_counter callback. That way we'll get the sw-cooked
counter for platforms without proper vblank support and so can ditch
the max_vblank_counter check again.
v4: Review from Michel Dänzer:
- Restore lost notes about v3:
- Spelling in kerneldoc.
- Inline wait_event condition.
- s/vblank_wait/wait_one_vblank/
Cc: Michel Dänzer <michel@daenzer.net>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Diffstat (limited to 'drivers/gpu/drm/drm_irq.c')
-rw-r--r-- | drivers/gpu/drm/drm_irq.c | 44 |
1 files changed, 44 insertions, 0 deletions
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c index 6f16a10..e64d249 100644 --- a/drivers/gpu/drm/drm_irq.c +++ b/drivers/gpu/drm/drm_irq.c @@ -1010,6 +1010,50 @@ 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 * @crtc: CRTC in question |