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/rs600.c b/drivers/gpu/drm/radeon/rs600.c
index 6364ba1..fd5ab01 100644
--- a/drivers/gpu/drm/radeon/rs600.c
+++ b/drivers/gpu/drm/radeon/rs600.c
@@ -388,6 +388,7 @@
 {
 	uint32_t status, msi_rearm;
 	uint32_t r500_disp_int;
+	bool queue_hotplug = false;
 
 	status = rs600_irq_ack(rdev, &r500_disp_int);
 	if (!status && !r500_disp_int) {
@@ -403,13 +404,17 @@
 		if (G_007EDC_LB_D2_VBLANK_INTERRUPT(r500_disp_int))
 			drm_handle_vblank(rdev->ddev, 1);
 		if (G_007EDC_DC_HOT_PLUG_DETECT1_INTERRUPT(r500_disp_int)) {
-			DRM_INFO("HPD1\n");
+			queue_hotplug = true;
+			DRM_DEBUG("HPD1\n");
 		}
 		if (G_007EDC_DC_HOT_PLUG_DETECT2_INTERRUPT(r500_disp_int)) {
-			DRM_INFO("HPD2\n");
+			queue_hotplug = true;
+			DRM_DEBUG("HPD2\n");
 		}
 		status = rs600_irq_ack(rdev, &r500_disp_int);
 	}
+	if (queue_hotplug)
+		queue_work(rdev->wq, &rdev->hotplug_work);
 	if (rdev->msi_enabled) {
 		switch (rdev->family) {
 		case CHIP_RS600: