video: iris33: ensure AON spare register to become zero

Poll for AON spare register BIT(0) to become zero before
asserting XO reset from video driver to ensure CVP/EVA driver
is not asserting XO reset around the same time. Asserting
XO reset by both driver at the same time may result in
unpredictable behavior.

Change-Id: I71a0bd0175ef7701c9a855abbf3c2e741d937dfb
Signed-off-by: Maheshwar Ajja <[email protected]>

driver/variant/iris33/src/msm_vidc_iris33.c

@@ -457,9 +457,13 @@ static int __power_off_iris33_controller(struct msm_vidc_core *core)
 	if (rc)
 		return rc;
 
-	rc = __read_register(core, AON_WRAPPER_SPARE, &value);
-	if (rc)
-		return rc;
+	/* poll AON spare register bit0 to become zero with 50ms timeout */
+	rc = __read_register_with_poll_timeout(core, AON_WRAPPER_SPARE,
+			0x1, 0x0, 1000, 50 * 1000);
+        if (rc)
+                d_vpr_e("%s: AON spare register is not zero\n", __func__);
+
+	/* enable bit(1) to avoid cvp noc xo reset */
 	rc = __write_register(core, AON_WRAPPER_SPARE, value|0x2);
 	if (rc)
 		return rc;
@@ -473,7 +477,7 @@ static int __power_off_iris33_controller(struct msm_vidc_core *core)
 	rc = __write_register_masked(core, AON_WRAPPER_MVP_NOC_CORE_SW_RESET,
 			0x0, BIT(0));
 	if (rc)
-		return rc;
+		d_vpr_e("%s: MVP_NOC_CORE_SW_RESET failed\n", __func__);
 
 	/* De-assert video_cc XO reset */
 	usleep_range(80, 100);
@@ -481,6 +485,11 @@ static int __power_off_iris33_controller(struct msm_vidc_core *core)
 	if (rc)
 		d_vpr_e("%s: deassert video_xo_reset failed\n", __func__);
 
+	/* reset AON spare register */
+	rc = __write_register(core, AON_WRAPPER_SPARE, 0x0);
+	if (rc)
+		return rc;
+
 	/* Enable MVP NoC clock */
 	rc = __write_register_masked(core, AON_WRAPPER_MVP_NOC_CORE_CLK_CONTROL,
 			0x0, BIT(0));