[Intel-gfx] [PATCH v5 13/22] drm/modes: Introduce the tv_mode property as a command-line option

[Noralf Trønnes]

Den 16.10.2022 19.51, skrev Mateusz Kwiatkowski:
> Hi Maxime, Noralf & everyone,
> 
> I'd like to address Noralf here in particular, and refer to these discussions
> from the past:
> 
> - https://lore.kernel.org/linux-arm-kernel/2f607c7d-6da1-c8df-1c02-8dd344a92343@gmail.com/
> - https://lore.kernel.org/linux-arm-kernel/9e76a508-f469-a54d-ecd7-b5868ca99af4@tronnes.org/
> 
>> @@ -2230,20 +2256,22 @@ struct drm_named_mode {
>>  	unsigned int xres;
>>  	unsigned int yres;
>>  	unsigned int flags;
>> +	unsigned int tv_mode;
>>  };
> 
> I saw that you (Noralf) opposed my suggestion about the DRM_MODE_TV_MODE_NONE
> enum value in enum drm drm_connector_tv_mode. I get your argumentation, and I'm
> not gonna argue, but I still don't like the fact that struct drm_named_mode now
> includes a field that is only relevant for analog TV modes, has no "none" value,
> and yet the type is supposed to be generic enough to be usable for other types
> of outputs as well.
> 
> It's true that it can just be ignored (as Maxime mentioned in his response to
> my e-mail linked above), and now the value of 0 corresponds to
> DRM_MODE_TV_MODE_NTSC, which is a rather sane default, but it still feels messy
> to me.
> 
> I'm not gonna force my opinion here, but I wanted to bring your attention to
> this issue, maybe you have some other solution in mind for this problem. Or if
> you don't see that as a problem at all, that's fine, too.
> 

I hadn't looked at this patch in detail before, but you're right this,
together with drm_atomic_helper_connector_tv_reset(), will overwrite
tv.mode unconditionally regardless of tv_mode being present in video= or
not. We need a tv_mode_specified flag like we have for bpp and refresh.

Noralf.