Re: [PATCH v4 08/39] drm/msm/dp: allow dp_ctrl stream APIs to use any panel passed to it

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

On 4/12/2026 1:38 AM, Dmitry Baryshkov wrote:
> On Fri, Apr 10, 2026 at 05:33:43PM +0800, Yongxing Mou wrote:
>> From: Abhinav Kumar <quic_abhinavk@quicinc.com>
>>
>> Currently, the dp_ctrl stream APIs operate on their own dp_panel
>> which is stored inside the dp_ctrl's private struct. However with MST,
>> the stored panel represents the fixed link and not the sinks which
>> are hotplugged. Allow the stream related APIs to work on the panel
>> which is passed to them rather than the stored one. For SST cases,
>> this shall continue to use the stored dp_panel.
> 
> Hmm. Why? Can't we get rid of it (in the followup patch)?
> 
In MST, the stream panel is bound to the connector, but in SST the panel 
is still stored in msm_dp_display_private and msm_dp_ctrl_private, so
   dropping it does not seem necessary at this point. The purpose of 
these changes is to allow the functions to operate on the MST panel data 
passed in per stream.
>>
>> 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_ctrl.c    | 21 +++++++++++----------
>>   drivers/gpu/drm/msm/dp/dp_ctrl.h    |  2 +-
>>   drivers/gpu/drm/msm/dp/dp_display.c |  2 +-
>>   3 files changed, 13 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.c b/drivers/gpu/drm/msm/dp/dp_ctrl.c
>> index cd58968d4e14..d0eed8c7df45 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_ctrl.c
>> +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.c
>> @@ -477,13 +477,14 @@ static void msm_dp_ctrl_config_misc1_misc0(struct msm_dp_ctrl_private *ctrl,
>>   	msm_dp_write_link(ctrl, REG_DP_MISC1_MISC0, misc_val);
>>   }
>>   
>> -static void msm_dp_ctrl_configure_source_params(struct msm_dp_ctrl_private *ctrl)
>> +static void msm_dp_ctrl_configure_source_params(struct msm_dp_ctrl_private *ctrl,
>> +						struct msm_dp_panel *msm_dp_panel)
>>   {
>> -	msm_dp_ctrl_config_ctrl_streams(ctrl, ctrl->panel);
>> +	msm_dp_ctrl_config_ctrl_streams(ctrl, msm_dp_panel);
>>   
>> -	msm_dp_ctrl_config_misc1_misc0(ctrl, ctrl->panel);
>> +	msm_dp_ctrl_config_misc1_misc0(ctrl, msm_dp_panel);
>>   
>> -	msm_dp_panel_timing_cfg(ctrl->panel, ctrl->msm_dp_ctrl.wide_bus_en);
>> +	msm_dp_panel_timing_cfg(msm_dp_panel, ctrl->msm_dp_ctrl.wide_bus_en);
>>   }
>>   
>>   /*
>> @@ -2523,7 +2524,7 @@ int msm_dp_ctrl_prepare_stream_on(struct msm_dp_ctrl *msm_dp_ctrl, bool force_li
>>   	return ret;
>>   }
>>   
>> -int msm_dp_ctrl_on_stream(struct msm_dp_ctrl *msm_dp_ctrl)
>> +int msm_dp_ctrl_on_stream(struct msm_dp_ctrl *msm_dp_ctrl, struct msm_dp_panel *msm_dp_panel)
>>   {
>>   	int ret = 0;
>>   	bool mainlink_ready = false;
>> @@ -2536,10 +2537,10 @@ int msm_dp_ctrl_on_stream(struct msm_dp_ctrl *msm_dp_ctrl)
>>   
>>   	ctrl = container_of(msm_dp_ctrl, struct msm_dp_ctrl_private, msm_dp_ctrl);
>>   
>> -	pixel_rate_orig = ctrl->panel->msm_dp_mode.drm_mode.clock;
>> +	pixel_rate_orig = msm_dp_panel->msm_dp_mode.drm_mode.clock;
>>   	pixel_rate = pixel_rate_orig;
>>   
>> -	if (msm_dp_ctrl->wide_bus_en || ctrl->panel->msm_dp_mode.out_fmt_is_yuv_420)
>> +	if (msm_dp_ctrl->wide_bus_en || msm_dp_panel->msm_dp_mode.out_fmt_is_yuv_420)
>>   		pixel_rate >>= 1;
>>   
>>   	drm_dbg_dp(ctrl->drm_dev, "pixel_rate=%lu\n", pixel_rate);
>> @@ -2571,14 +2572,14 @@ int msm_dp_ctrl_on_stream(struct msm_dp_ctrl *msm_dp_ctrl)
>>   	msm_dp_setup_peripheral_flush(ctrl);
>>   	msm_dp_ctrl_config_ctrl_link(ctrl);
>>   
>> -	msm_dp_ctrl_configure_source_params(ctrl);
>> +	msm_dp_ctrl_configure_source_params(ctrl, msm_dp_panel);
>>   
>>   	msm_dp_ctrl_config_msa(ctrl,
>>   		ctrl->link->link_params.rate,
>>   		pixel_rate_orig,
>> -		ctrl->panel->msm_dp_mode.out_fmt_is_yuv_420);
>> +		msm_dp_panel->msm_dp_mode.out_fmt_is_yuv_420);
>>   
>> -	msm_dp_panel_clear_dsc_dto(ctrl->panel);
>> +	msm_dp_panel_clear_dsc_dto(msm_dp_panel);
>>   
>>   	msm_dp_ctrl_setup_tr_unit(ctrl);
>>   
>> diff --git a/drivers/gpu/drm/msm/dp/dp_ctrl.h b/drivers/gpu/drm/msm/dp/dp_ctrl.h
>> index 5d615f50d13b..32196e97cbe9 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_ctrl.h
>> +++ b/drivers/gpu/drm/msm/dp/dp_ctrl.h
>> @@ -17,7 +17,7 @@ struct msm_dp_ctrl {
>>   struct phy;
>>   
>>   int msm_dp_ctrl_on_link(struct msm_dp_ctrl *msm_dp_ctrl);
>> -int msm_dp_ctrl_on_stream(struct msm_dp_ctrl *msm_dp_ctrl);
>> +int msm_dp_ctrl_on_stream(struct msm_dp_ctrl *msm_dp_ctrl, struct msm_dp_panel *msm_dp_panel);
>>   int msm_dp_ctrl_prepare_stream_on(struct msm_dp_ctrl *msm_dp_ctrl, bool force_link_train);
>>   void msm_dp_ctrl_off(struct msm_dp_ctrl *msm_dp_ctrl);
>>   void msm_dp_ctrl_push_idle(struct msm_dp_ctrl *msm_dp_ctrl);
>> diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
>> index 58c46d5ab4d8..1bf1335712bc 100644
>> --- a/drivers/gpu/drm/msm/dp/dp_display.c
>> +++ b/drivers/gpu/drm/msm/dp/dp_display.c
>> @@ -666,7 +666,7 @@ static int msm_dp_display_enable(struct msm_dp_display_private *dp)
>>   		return 0;
>>   	}
>>   
>> -	rc = msm_dp_ctrl_on_stream(dp->ctrl);
>> +	rc = msm_dp_ctrl_on_stream(dp->ctrl, dp->panel);
>>   	if (!rc)
>>   		msm_dp_display->power_on = true;
>>   
>>
>> -- 
>> 2.43.0
>>
>