drm/msm/dp: update is_connected status base on sink count at dp_pm_resume()
PATCH v3 1/1 drm/msm/dp: update is_connected status base on sink count at dp_pm_resume()
Currently at dp_pm_resume() is_connected state is decided base on hpd connection status only. This will put is_connected in wrongly "true" state at the scenario that dongle attached to DUT but without hmdi cable connecting to it. Fix this problem by adding read sink count from dongle and decided is_connected state base on both sink count and hpd connection status.
Changes in v2:
-- remove dp_get_sink_count() cand call drm_dp_read_sink_count()
Changes in v3:
-- delete status local variable from dp_pm_resume()
--- drivers/gpu/drm/msm/dp/dp_display.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-)
drivers/gpu/drm/msm/dp/dp_display.c +15 -3
@@ -1313,7 +1313,7 @@ static int dp_pm_resume(struct device *dev)struct platform_device *pdev =to_platform_device (dev);struct msm_dp *dp_display =platform_get_drvdata (pdev);struct dp_display_private *dp; -u32 status; +int sink_count =0 ; dp = container_of(dp_display, struct dp_display_private, dp_display);
@@ -1327,14 +1327,26 @@ static int dp_pm_resume(struct device *dev)dp_catalog_ctrl_hpd_config (dp->catalog); - status =dp_catalog_link_is_connected (dp->catalog); +/* +* set sink to normal operation mode -- D0 +* before dpcd read +*/ +dp_link_psm_config (dp->link, &dp->panel->link_info, false); + +/* if sink conencted, do dpcd read sink count */ +if (dp_catalog_link_is_connected (dp->catalog)) { + sink_count =drm_dp_read_sink_count (dp->aux); +if (sink_count <0 ) + sink_count =0 ; + } + dp->link->sink_count = sink_count;/* * 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) +if (dp->link->sink_count) dp->dp_display.is_connected = true;else dp->dp_display.is_connected = false;
Signature · 2 lines
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Quoting Kuogee Hsieh (2021-08-03 09:25:13)
Quoted 33 lines
Currently at
dp_pm_resume()is_connectedstate is decided base on hpd connection status only. This will putis_connectedin wrongly "true" state at the scenario that dongle attached to DUT but without hmdi cable connecting to it. Fix this problem by adding read sink count from dongle and decidedis_connectedstate base on both sink count and hpd connection status.Changes in v2:
-- removedp_get_sink_count()cand calldrm_dp_read_sink_count()Changes in v3:
-- delete status local variable fromdp_pm_resume()Fixes d9aa6571b28ba ("drm/msm/dp: check sink_count before update is_connected status")Signed-off-by Kuogee Hsieh <[email protected]>--- drivers/gpu/drm/msm/dp/dp_display.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-)drivers/gpu/drm/msm/dp/dp_display.c +1
-1@@ -1313,7 +1313,7 @@ static int dp_pm_resume(struct device *dev)struct platform_device *pdev =to_platform_device (dev);struct msm_dp *dp_display =platform_get_drvdata (pdev);struct dp_display_private *dp; -u32 status; +int sink_count =0 ; dp = container_of(dp_display, struct dp_display_private, dp_display);@@ -1327,14 +1327,26 @@ static int dp_pm_resume(struct device *dev)
drivers/gpu/drm/msm/dp/dp_display.c static int dp_pm_resume(struct device *dev) · line 1336
Quoted 10 lines
drivers/gpu/drm/msm/dp/dp_display.c +7
-1dp_catalog_ctrl_hpd_config (dp->catalog); - status =dp_catalog_link_is_connected (dp->catalog); +/* +* set sink to normal operation mode -- D0 +* before dpcd read +*/ +dp_link_psm_config (dp->link, &dp->panel->link_info, false); + +/* if sink conencted, do dpcd read sink count */
s/conencted/connected/
This also just says what the code is doing. Why do we only read the sink count if the link is connected? Can we read the sink count even if the link isn't connected and then consider sink count as 0 if trying to read fails?
Quoted 17 lines
drivers/gpu/drm/msm/dp/dp_display.c +7
-1+if (dp_catalog_link_is_connected (dp->catalog)) { + sink_count =drm_dp_read_sink_count (dp->aux); +if (sink_count <0 ) + sink_count =0 ; + } + dp->link->sink_count = sink_count;/* * 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) +if (dp->link->sink_count) dp->dp_display.is_connected = true;else dp->dp_display.is_connected = false;
Quoted 48 lines · Stephen Boyd
Quoting Kuogee Hsieh (2021-08-03 09:25:13)
Quoted 34 lines
Currently at
dp_pm_resume()is_connectedstate is decided base on hpd connection status only. This will putis_connectedin wrongly "true" state at the scenario that dongle attached to DUT but without hmdi cable connecting to it. Fix this problem by adding read sink count from dongle and decidedis_connectedstate base on both sink count and hpd connection status.Changes in v2:
-- removedp_get_sink_count()cand calldrm_dp_read_sink_count()Changes in v3:
-- delete status local variable fromdp_pm_resume()Fixes d9aa6571b28ba ("drm/msm/dp: check sink_count before update is_connected status")Signed-off-by Kuogee Hsieh <[email protected]>--- drivers/gpu/drm/msm/dp/dp_display.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-)drivers/gpu/drm/msm/dp/dp_display.c +1
-1@@ -1313,7 +1313,7 @@ static int dp_pm_resume(struct device *dev)struct platform_device *pdev =to_platform_device (dev);struct msm_dp *dp_display =platform_get_drvdata (pdev);struct dp_display_private *dp; -u32 status; +int sink_count =0 ; dp = container_of(dp_display, struct dp_display_private, dp_display);@@ -1327,14 +1327,26 @@ static int dp_pm_resume(struct device *dev)drivers/gpu/drm/msm/dp/dp_display.c static int dp_pm_resume(struct device *dev) · line 1336
Quoted 10 lines
drivers/gpu/drm/msm/dp/dp_display.c +7
-1dp_catalog_ctrl_hpd_config (dp->catalog); - status =dp_catalog_link_is_connected (dp->catalog); +/* +* set sink to normal operation mode -- D0 +* before dpcd read +*/ +dp_link_psm_config (dp->link, &dp->panel->link_info, false); + +/* if sink conencted, do dpcd read sink count */ s/conencted/connected/
Quoted 5 lines
This also just says what the code is doing. Why do we only read the sink count if the link is connected? Can we read the sink count even if the link isn't connected and then consider sink count as 0 if trying to read fails?
yes, we can do that.
But it will suffer aux time out and retry.
i think it is better to avoid this overhead by check connection first.
Quoted 17 lines
Quoted 17 lines
drivers/gpu/drm/msm/dp/dp_display.c +7
-1+if (dp_catalog_link_is_connected (dp->catalog)) { + sink_count =drm_dp_read_sink_count (dp->aux); +if (sink_count <0 ) + sink_count =0 ; + } + dp->link->sink_count = sink_count;/* * 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) +if (dp->link->sink_count) dp->dp_display.is_connected = true;else dp->dp_display.is_connected = false;
Quoting [email protected] (2021-08-04 08:48:04)
Quoted 24 lines · Stephen Boyd
Quoted 16 lines
Quoting Kuogee Hsieh (2021-08-03 09:25:13)
drivers/gpu/drm/msm/dp/dp_display.c static int dp_pm_resume(struct device *dev) · line 1336
Quoted 12 lines
drivers/gpu/drm/msm/dp/dp_display.c +7
-1@@ -1327,14 +1327,26 @@ static int dp_pm_resume(struct device *dev)dp_catalog_ctrl_hpd_config (dp->catalog); - status =dp_catalog_link_is_connected (dp->catalog); +/* +* set sink to normal operation mode -- D0 +* before dpcd read +*/ +dp_link_psm_config (dp->link, &dp->panel->link_info, false); + +/* if sink conencted, do dpcd read sink count */ s/conencted/connected/
Quoted 7 lines
This also just says what the code is doing. Why do we only read the sink
count if the link is connected? Can we read the sink count even if the link isn't connected and then consider sink count as 0 if trying to read
fails?
Quoted 4 lines
yes, we can do that.
But it will suffer aux time out and retry.
i think it is better to avoid this overhead by check connection first.
Hmm ok. Maybe something is wrong with the aux channel where it doesn't avoid the timeout if the connection is obviously not established yet.