drm/omap: DMM: Print information if we received an error interrupt

To help diagnose DMM errors, print out information if any of the error bits
are set in the interrupt status register.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
diff --git a/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c b/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
index 5a18f0e..09d0973 100644
--- a/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
+++ b/drivers/gpu/drm/omapdrm/omap_dmm_tiler.c
@@ -166,6 +166,11 @@
 	dmm_write(dmm, status, DMM_PAT_IRQSTATUS);
 
 	for (i = 0; i < dmm->num_engines; i++) {
+		if (status & DMM_IRQSTAT_ERR_MASK)
+			dev_err(dmm->dev,
+				"irq error(engine%d): IRQSTAT 0x%02x\n",
+				i, status & 0xff);
+
 		if (status & DMM_IRQSTAT_LST) {
 			if (dmm->engines[i].async)
 				release_engine(&dmm->engines[i]);