[PATCH] drm/i915: Disable high-precision vblank timestamping for UMS

We only have sufficient information for accurate (sub-frame) timestamping when the modesetting is under our control.

Reported-by: Chris Clayton chris2553@googlemail.com Signed-off-by: Chris Wilson chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/i915_drv.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index 59eb19b..66796bb 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -752,6 +752,9 @@ static int __init i915_init(void) driver.driver_features &= ~DRIVER_MODESET; #endif

+ if (!(driver.driver_features & DRIVER_MODESET)) + driver.get_vblank_timestamp = NULL; + return drm_init(&driver); }