drm/i915: Can't do accurate vblank timestamps with UMS
Disable this feature when KMS is not running by setting the
driver->get_vblank_timestamp function pointer to NULL.
Signed-off-by: Keith Packard <keithp@keithp.com>
Tested-by: Justin P. Mattock <justinmattock@gmail.com>
diff --git a/drivers/gpu/drm/i915/i915_irq.c b/drivers/gpu/drm/i915/i915_irq.c
index 02f96fd..9cbb0cd 100644
--- a/drivers/gpu/drm/i915/i915_irq.c
+++ b/drivers/gpu/drm/i915/i915_irq.c
@@ -2058,8 +2058,10 @@
dev->driver->get_vblank_counter = gm45_get_vblank_counter;
}
-
- dev->driver->get_vblank_timestamp = i915_get_vblank_timestamp;
+ if (drm_core_check_feature(dev, DRIVER_MODESET))
+ dev->driver->get_vblank_timestamp = i915_get_vblank_timestamp;
+ else
+ dev->driver->get_vblank_timestamp = NULL;
dev->driver->get_scanout_position = i915_get_crtc_scanoutpos;
if (IS_IVYBRIDGE(dev)) {