[v2,1/3] drm/msm/dp: check sink_count before update is_connected status
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Message ID 1618355470-5226-1-git-send-email-khsieh@codeaurora.org
State New, archived
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  • [v2,1/3] drm/msm/dp: check sink_count before update is_connected status
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Commit Message

Kuogee Hsieh April 13, 2021, 11:11 p.m. UTC
Link status is different from display connected status in the case
of something like an Apple dongle where the type-c plug can be
connected, and therefore the link is connected, but no sink is
connected until an HDMI cable is plugged into the dongle.
The sink_count of DPCD of dongle will increase to 1 once an HDMI
cable is plugged into the dongle so that display connected status
will become true. This checking also apply at pm_resume.

Fixes: 94e58e2d06e3 ("drm/msm/dp: reset dp controller only at boot up and pm_resume")
Reported-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
---
 drivers/gpu/drm/msm/dp/dp_display.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

Comments

Stephen Boyd April 14, 2021, 2:41 a.m. UTC | #1
Quoting Kuogee Hsieh (2021-04-13 16:11:10)
> Link status is different from display connected status in the case
> of something like an Apple dongle where the type-c plug can be
> connected, and therefore the link is connected, but no sink is
> connected until an HDMI cable is plugged into the dongle.
> The sink_count of DPCD of dongle will increase to 1 once an HDMI
> cable is plugged into the dongle so that display connected status
> will become true. This checking also apply at pm_resume.
> 
> Fixes: 94e58e2d06e3 ("drm/msm/dp: reset dp controller only at boot up and pm_resume")
> Reported-by: Stephen Boyd <swboyd@chromium.org>
> Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
> ---

Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Tested-by: Stephen Boyd <swboyd@chromium.org>

Patch
diff mbox series

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 5a39da6..0ba71c7 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -586,10 +586,8 @@  static int dp_connect_pending_timeout(struct dp_display_private *dp, u32 data)
 	mutex_lock(&dp->event_mutex);
 
 	state = dp->hpd_state;
-	if (state == ST_CONNECT_PENDING) {
-		dp_display_enable(dp, 0);
+	if (state == ST_CONNECT_PENDING)
 		dp->hpd_state = ST_CONNECTED;
-	}
 
 	mutex_unlock(&dp->event_mutex);
 
@@ -669,10 +667,8 @@  static int dp_disconnect_pending_timeout(struct dp_display_private *dp, u32 data
 	mutex_lock(&dp->event_mutex);
 
 	state =  dp->hpd_state;
-	if (state == ST_DISCONNECT_PENDING) {
-		dp_display_disable(dp, 0);
+	if (state == ST_DISCONNECT_PENDING)
 		dp->hpd_state = ST_DISCONNECTED;
-	}
 
 	mutex_unlock(&dp->event_mutex);
 
@@ -1272,7 +1268,12 @@  static int dp_pm_resume(struct device *dev)
 
 	status = dp_catalog_link_is_connected(dp->catalog);
 
-	if (status)
+	/*
+	 * can not declared display is connected unless
+	 * HDMI cable is plugged in and sink_count of
+	 * dongle become 1
+	 */
+	if (status && dp->link->sink_count)
 		dp->dp_display.is_connected = true;
 	else
 		dp->dp_display.is_connected = false;