Re: [PATCH v3 32/38] drm/msm/dp: propagate MST state changes to dp mst module

[Yongxing Mou <yongxing.mou@oss.qualcomm.com>]

On 8/27/2025 2:43 AM, Dmitry Baryshkov wrote:
> On Mon, Aug 25, 2025 at 10:16:18PM +0800, Yongxing Mou wrote:
>> Introduce APIs to update the MST state change to MST framework when
>> device is plugged/unplugged.
>>
>> Signed-off-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
>> Signed-off-by: Yongxing Mou <yongxing.mou@oss.qualcomm.com>
>> ---
>>   drivers/gpu/drm/msm/dp/dp_display.c | 10 +++++++++-
>>   drivers/gpu/drm/msm/dp/dp_mst_drm.c | 15 +++++++++++++++
>>   drivers/gpu/drm/msm/dp/dp_mst_drm.h |  1 +
>>   3 files changed, 25 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
>> index 59720e1ad4b1193e33a4fc6aad0c401eaf9cbec8..909c84a5c97f56138d0d62c5d856d2fd18d36b8c 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_display.c
>> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
>> @@ -28,6 +28,7 @@
>>   #include "dp_drm.h"
>>   #include "dp_audio.h"
>>   #include "dp_debug.h"
>> +#include "dp_mst_drm.h"
>>   
>>   static bool psr_enabled = false;
>>   module_param(psr_enabled, bool, 0);
>> @@ -269,7 +270,6 @@ static int msm_dp_display_send_hpd_notification(struct msm_dp_display_private *d
>>   		dp->panel->video_test = false;
>>   	}
>>   
>> -
> 
> Unrelated
> 
Will drop it.
>>   	drm_dbg_dp(dp->drm_dev, "type=%d hpd=%d\n",
>>   			dp->msm_dp_display.connector_type, hpd);
>>   
>> @@ -386,6 +386,9 @@ static int msm_dp_display_process_hpd_high(struct msm_dp_display_private *dp)
>>   
>>   	msm_dp_link_reset_phy_params_vx_px(dp->link);
>>   
>> +	if (dp->msm_dp_display.mst_active)
>> +		msm_dp_mst_display_set_mgr_state(&dp->msm_dp_display, true);
> 
> I'd say, this should be a part of the previous patch.
> 
Will rework this chunk.
>> +
>>   	if (!dp->msm_dp_display.internal_hpd)
>>   		msm_dp_display_send_hpd_notification(dp, true);
>>   
>> @@ -608,6 +611,11 @@ static int msm_dp_hpd_unplug_handle(struct msm_dp_display_private *dp, u32 data)
>>   	if (!dp->msm_dp_display.internal_hpd)
>>   		msm_dp_display_send_hpd_notification(dp, false);
>>   
>> +	if (dp->msm_dp_display.mst_active) {
>> +		msm_dp_mst_display_set_mgr_state(&dp->msm_dp_display, false);
>> +		dp->msm_dp_display.mst_active = false;
>> +	}
>> +
>>   	/* signal the disconnect event early to ensure proper teardown */
>>   	msm_dp_display_handle_plugged_change(&dp->msm_dp_display, false);
>>   
>> diff --git a/drivers/gpu/drm/msm/dp/dp_mst_drm.c b/drivers/gpu/drm/msm/dp/dp_mst_drm.c
>> index 331d08854049d9c74d49aa231f3507539986099e..ca654b1963467c8220dd7ee073f25216455d0490 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_mst_drm.c
>> +++ b/drivers/gpu/drm/msm/dp/dp_mst_drm.c
>> @@ -924,6 +924,21 @@ msm_dp_mst_add_connector(struct drm_dp_mst_topology_mgr *mgr,
>>   	return connector;
>>   }
>>   
>> +int msm_dp_mst_display_set_mgr_state(struct msm_dp *dp_display, bool state)
>> +{
>> +	int rc;
>> +	struct msm_dp_mst *mst = dp_display->msm_dp_mst;
> 
> Reverse X-mas
> 
Got it.
>> +
>> +	rc = drm_dp_mst_topology_mgr_set_mst(&mst->mst_mgr, state);
>> +	if (rc < 0) {
>> +		DRM_ERROR("failed to set topology mgr state to %d. rc %d\n",
>> +			  state, rc);
>> +	}
>> +
>> +	drm_dbg_dp(dp_display->drm_dev, "dp_mst_display_set_mgr_state state:%d\n", state);
>> +	return rc;
>> +}
>> +
>>   static const struct drm_dp_mst_topology_cbs msm_dp_mst_drm_cbs = {
>>   	.add_connector = msm_dp_mst_add_connector,
>>   };
>> diff --git a/drivers/gpu/drm/msm/dp/dp_mst_drm.h b/drivers/gpu/drm/msm/dp/dp_mst_drm.h
>> index 5e1b4db8aea4506b0e1cc1cc68980dd617d3f72a..8fe6cbbe741da4abb232256b3a15ba6b16ca4f3e 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_mst_drm.h
>> +++ b/drivers/gpu/drm/msm/dp/dp_mst_drm.h
>> @@ -87,5 +87,6 @@ int msm_dp_mst_drm_bridge_init(struct msm_dp *dp, struct drm_encoder *encoder);
>>   int msm_dp_mst_init(struct msm_dp *dp_display, u32 max_streams, struct drm_dp_aux *drm_aux);
>>   
>>   void msm_dp_mst_display_hpd_irq(struct msm_dp *dp_display);
>> +int msm_dp_mst_display_set_mgr_state(struct msm_dp *dp_display, bool state);
>>   
>>   #endif /* _DP_MST_DRM_H_ */
>>
>> -- 
>> 2.34.1
>>
>