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Date:   Wed, 23 Feb 2022 19:34:54 +0100
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Subject: Re: [PATCH v3] simplefb: Enable boot time VESA graphic mode
 selection.
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To:     =?UTF-8?Q?Michal_Such=c3=a1nek?= <msuchanek@suse.de>
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From:   Javier Martinez Canillas <javierm@redhat.com>
In-Reply-To: <20220223182341.GG3113@kunlun.suse.cz>
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On 2/23/22 19:23, Michal Suchánek wrote:

[snip]

>> My point about the subject line remains thought, I would use something like:
>>
>> firmware: sysfb: Enable boot time VESA graphic mode selection for simplefb
> 
> I see where the confusion comes from.
>

Yeah. And just to clarify, the "simplefb" in the subject line I proposed
was about the sysfb simplefb and not the fbdev simplefb :)
 
> The efifb (and probably vesafb) has implicit unstated dependency on
> sysfb. So the drivers that select BOOT_VESA_SUPPORT should instead
> depend on SYSFB, and then SYSFB can select BOOT_VESA_SUPPORT, and it
> will look much saner.
>

That indeed would be much nicer. And I agree with you that there's an
implicit dependency that should be made explicit since SYSFB is what
registers the "efi-framebuffer" or "vesa-framebuffer" if SYSFB_SIMPLEFB
is not enabled.

Should SYSFB should only select BOOT_VESA_SUPPORT if x86 ? I know that
in practice shouldn't matter because BOOT_VESA_SUPPORT is under x86 but
I guess is more correct if that's the case.

And I think that FB_SIMPLE should depend on SYSFB_SIMPLEFB if !OF (since
a "simple-framebuffer" platform device could be registered by OF if a
Device Tree node with compatible "simple-framebuffer" exists).

Best regards, -- 
Javier Martinez Canillas
Linux Engineering
Red Hat