drm/radeon/kms: enable hpd support

This enabled interrupt driven hpd support for all
radeon chips.  Assuming the hpd pin is wired up
correctly, the driver will generate uevents on
digital monitor connect and disconnect and retrain
DP monitors automatically.

Signed-off-by: Alex Deucher <alexdeucher@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/radeon/radeon.h b/drivers/gpu/drm/radeon/radeon.h
index 29c6e0a..a15cf9c 100644
--- a/drivers/gpu/drm/radeon/radeon.h
+++ b/drivers/gpu/drm/radeon/radeon.h
@@ -809,6 +809,8 @@
 	struct r600_blit r600_blit;
 	int msi_enabled; /* msi enabled */
 	struct r600_ih ih; /* r6/700 interrupt ring */
+	struct workqueue_struct *wq;
+	struct work_struct hotplug_work;
 };
 
 int radeon_device_init(struct radeon_device *rdev,