[PATCH v6 7/9] drm/msm: dp: handle the IRQ_HPD events reported by USB-C

[Dmitry Baryshkov]

The DisplayPort standard defines a special kind of HPD events called
IRQ_HPD. These events are used to notify DP Source about the events on
the Sink side, for example DP MST events.

Let the MSM DisplayPort driver properly track and handle IRQ_HPD
delivered over the OOB events (e.g. from the USB-C AltMode handler).

Reviewed-by: Pengyu Luo <mitltlatltl at gmail.com>
Acked-by: Heikki Krogerus <heikki.krogerus at linux.intel.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at oss.qualcomm.com>
---
 drivers/gpu/drm/msm/dp/dp_display.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index ce919a26fba2..6a8b3b8e1fe7 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -1566,11 +1566,13 @@ void msm_dp_bridge_hpd_notify(struct drm_bridge *bridge,
 		if (hpd_link_status == ISR_HPD_REPLUG_COUNT) {
 			msm_dp_hpd_unplug_handle(dp);
 			msm_dp_hpd_plug_handle(dp);
-		} else if (hpd_link_status == ISR_IRQ_HPD_PULSE_COUNT) {
-			msm_dp_irq_hpd_handle(dp);
 		} else {
 			msm_dp_hpd_plug_handle(dp);
 		}
+
+		if (hpd_link_status == ISR_IRQ_HPD_PULSE_COUNT ||
+		    event == DRM_CONNECTOR_DP_IRQ_HPD) {
+			msm_dp_irq_hpd_handle(dp);
 	} else {
 		msm_dp_hpd_unplug_handle(dp);
 	}

-- 
2.47.3