drm/msm/hdmi: rework HDMI IRQ handler

Disable the HPD interrupt when acking it, to avoid spurious
interrupt.
Signed-off-by: Jilai Wang <jilaiw@codeaurora.org>

drivers/gpu/drm/msm/hdmi/hdmi_connector.c

@@ -251,11 +251,11 @@ void hdmi_connector_irq(struct drm_connector *connector)
 			(hpd_int_status & HDMI_HPD_INT_STATUS_INT)) {
 		bool detected = !!(hpd_int_status & HDMI_HPD_INT_STATUS_CABLE_DETECTED);
 
-		DBG("status=%04x, ctrl=%04x", hpd_int_status, hpd_int_ctrl);
-
-		/* ack the irq: */
+		/* ack & disable (temporarily) HPD events: */
 		hdmi_write(hdmi, REG_HDMI_HPD_INT_CTRL,
-				hpd_int_ctrl | HDMI_HPD_INT_CTRL_INT_ACK);
+			HDMI_HPD_INT_CTRL_INT_ACK);
+
+		DBG("status=%04x, ctrl=%04x", hpd_int_status, hpd_int_ctrl);
 
 		/* detect disconnect if we are connected or visa versa: */
 		hpd_int_ctrl = HDMI_HPD_INT_CTRL_INT_EN;