drm/i915: lock around link status and link training.
We need to take the connection mutex around the link status
check for non-MST case, but also around the MST link training
on short HPDs.
I suspect we actually should have a dpcd lock in the future as
well, that just lock the local copies of dpcd and flags stored
from that.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index ea6ff71..eb52ecf 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -3535,11 +3535,13 @@
void
intel_dp_check_link_status(struct intel_dp *intel_dp)
{
+ struct drm_device *dev = intel_dp_to_dev(intel_dp);
struct intel_encoder *intel_encoder = &dp_to_dig_port(intel_dp)->base;
u8 sink_irq_vector;
u8 link_status[DP_LINK_STATUS_SIZE];
- /* FIXME: This access isn't protected by any locks. */
+ WARN_ON(!drm_modeset_is_locked(&dev->mode_config.connection_mutex));
+
if (!intel_encoder->connectors_active)
return;
@@ -4058,7 +4060,9 @@
* we'll check the link status via the normal hot plug path later -
* but for short hpds we should check it now
*/
+ drm_modeset_lock(&dev->mode_config.connection_mutex, NULL);
intel_dp_check_link_status(intel_dp);
+ drm_modeset_unlock(&dev->mode_config.connection_mutex);
}
}
return false;