drm/vblank: Switch drm_driver->get_vblank_timestamp to return a bool
There's really no reason for anything more:
- Calling this while the crtc vblank stuff isn't set up is a driver
bug. Those places alrready DRM_ERROR.
- Calling this when the crtc is off is either a driver bug (calling
drm_crtc_handle_vblank at the wrong time) or a core bug (for
anything else). Again, we DRM_ERROR.
- EINVAL is checked at higher levels already, and if we'd use struct
drm_crtc * instead of (dev, pipe) it would be real obvious that
those are again core bugs.
The only valid failure mode is crap hardware that couldn't sample a
useful timestamp, to ask the core to just grab a not-so-accurate
timestamp. Bool is perfectly fine for that.
v2: Also fix up the one caller, I lost that in the shuffling (Jani).
v3: Fixup commit message (Neil).
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
Cc: Eric Anholt <eric@anholt.net>
Cc: Rob Clark <robdclark@gmail.com>
Cc: linux-arm-msm@vger.kernel.org
Cc: freedreno@lists.freedesktop.org
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Cc: Ben Skeggs <bskeggs@redhat.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Acked-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170509140329.24114-1-daniel.vetter@ffwll.ch
diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 8c866ca..677b37b 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -724,43 +724,32 @@ EXPORT_SYMBOL(drm_calc_timestamping_constants);
* active. Higher level code is expected to handle this.
*
* Returns:
- * Negative value on error, failure or if not supported in current
- * video mode:
*
- * -EINVAL Invalid CRTC.
- * -EAGAIN Temporary unavailable, e.g., called before initial modeset.
- * -ENOTSUPP Function not supported in current display mode.
- * -EIO Failed, e.g., due to failed scanout position query.
- *
- * Returns or'ed positive status flags on success:
- *
- * DRM_VBLANKTIME_SCANOUTPOS_METHOD - Signal this method used for timestamping.
- * DRM_VBLANKTIME_INVBL - Timestamp taken while scanout was in vblank interval.
- *
+ * Returns true on success, and false on failure, i.e. when no accurate
+ * timestamp could be acquired.
*/
-int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
- unsigned int pipe,
- int *max_error,
- struct timeval *vblank_time,
- unsigned flags,
- const struct drm_display_mode *mode)
+bool drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
+ unsigned int pipe,
+ int *max_error,
+ struct timeval *vblank_time,
+ unsigned flags,
+ const struct drm_display_mode *mode)
{
struct timeval tv_etime;
ktime_t stime, etime;
unsigned int vbl_status;
- int ret = DRM_VBLANKTIME_SCANOUTPOS_METHOD;
int vpos, hpos, i;
int delta_ns, duration_ns;
if (pipe >= dev->num_crtcs) {
DRM_ERROR("Invalid crtc %u\n", pipe);
- return -EINVAL;
+ return false;
}
/* Scanout position query not supported? Should not happen. */
if (!dev->driver->get_scanout_position) {
DRM_ERROR("Called from driver w/o get_scanout_position()!?\n");
- return -EIO;
+ return false;
}
/* If mode timing undefined, just return as no-op:
@@ -768,7 +757,7 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
*/
if (mode->crtc_clock == 0) {
DRM_DEBUG("crtc %u: Noop due to uninitialized mode.\n", pipe);
- return -EAGAIN;
+ return false;
}
/* Get current scanout position with system timestamp.
@@ -792,7 +781,7 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
if (!(vbl_status & DRM_SCANOUTPOS_VALID)) {
DRM_DEBUG("crtc %u : scanoutpos query failed [0x%x].\n",
pipe, vbl_status);
- return -EIO;
+ return false;
}
/* Compute uncertainty in timestamp of scanout position query. */
@@ -836,7 +825,7 @@ int drm_calc_vbltimestamp_from_scanoutpos(struct drm_device *dev,
(long)vblank_time->tv_sec, (long)vblank_time->tv_usec,
duration_ns/1000, i);
- return ret;
+ return true;
}
EXPORT_SYMBOL(drm_calc_vbltimestamp_from_scanoutpos);
@@ -872,25 +861,23 @@ static bool
drm_get_last_vbltimestamp(struct drm_device *dev, unsigned int pipe,
struct timeval *tvblank, unsigned flags)
{
- int ret;
+ bool ret = false;
/* Define requested maximum error on timestamps (nanoseconds). */
int max_error = (int) drm_timestamp_precision * 1000;
/* Query driver if possible and precision timestamping enabled. */
- if (dev->driver->get_vblank_timestamp && (max_error > 0)) {
+ if (dev->driver->get_vblank_timestamp && (max_error > 0))
ret = dev->driver->get_vblank_timestamp(dev, pipe, &max_error,
tvblank, flags);
- if (ret > 0)
- return true;
- }
/* GPU high precision timestamp query unsupported or failed.
* Return current monotonic/gettimeofday timestamp as best estimate.
*/
- *tvblank = get_drm_timestamp();
+ if (!ret)
+ *tvblank = get_drm_timestamp();
- return false;
+ return ret;
}
/**
