[PATCH 03/13] drm/amd/display: parse display name from drm_eld

[Melissa Wen]

On 14/04/2025 07:10, Jani Nikula wrote:
> On Fri, 11 Apr 2025, Melissa Wen <mwen at igalia.com> wrote:
>> We don't need to parse dc_edid to get the display name since it's
>> already set in drm_eld which in turn had it values updated when updating
>> connector with the opaque drm_edid.
>>
>> Signed-off-by: Melissa Wen <mwen at igalia.com>
>> ---
>>   .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c  | 10 ++++++----
>>   1 file changed, 6 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
>> index e93adb7e48a5..faea6b7fb3f3 100644
>> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
>> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
>> @@ -34,7 +34,7 @@
>>   #include <drm/amdgpu_drm.h>
>>   #include <drm/drm_edid.h>
>>   #include <drm/drm_fixed.h>
>> -
>> +#include <drm/drm_eld.h>
>>   #include "dm_services.h"
>>   #include "amdgpu.h"
>>   #include "dc.h"
>> @@ -90,6 +90,7 @@ static void apply_edid_quirks(struct drm_device *dev, struct edid *edid, struct
>>   	}
>>   }
>>   
>> +#define AMDGPU_ELD_DISPLAY_NAME_SIZE_IN_CHARS 13
>>   /**
>>    * dm_helpers_parse_edid_caps() - Parse edid caps
>>    *
>> @@ -132,9 +133,10 @@ enum dc_edid_status dm_helpers_parse_edid_caps(
>>   	edid_caps->manufacture_week = product_id.week_of_manufacture;
>>   	edid_caps->manufacture_year = product_id.year_of_manufacture;
>>   
>> -	drm_edid_get_monitor_name(edid_buf,
>> -				  edid_caps->display_name,
>> -				  AUDIO_INFO_DISPLAY_NAME_SIZE_IN_CHARS);
>> +	memset(edid_caps->display_name, 0, AUDIO_INFO_DISPLAY_NAME_SIZE_IN_CHARS);
>> +	memcpy(edid_caps->display_name,
>> +	       &connector->eld[DRM_ELD_MONITOR_NAME_STRING],
>> +	       AMDGPU_ELD_DISPLAY_NAME_SIZE_IN_CHARS);
> It's not that simple. The monitor name in ELD is not fixed length (see
> drm_eld_mnl()) and neither is it guaranteed to be NUL terminated.
I see. Thanks for raising these points.
I need to looking for a better solution then.

Melissa
>
> BR,
> Jani.
>
>
>>   
>>   	edid_caps->edid_hdmi = connector->display_info.is_hdmi;