Re: [PATCH 2/2] ata: make PATA_PLATFORM selectable only for suitable architectures

[Arnd Bergmann]

On Wed, Sep 14, 2022, at 4:27 PM, Lukas Bulwahn wrote:
> It is currently possible to select "Generic platform device PATA support"
> in two situations:
>
>   - architecture allows the generic platform device PATA support and
>     indicates that with "select HAVE_PATA_PLATFORM".
>   - if the user claims to be an EXPERT by setting CONFIG_EXPERT to yes
>
> However, there is no use case to have Generic platform device PATA support
> in a kernel build if the architecture definition, i.e., the selection of
> configs by an architecture, does not support it.
>
> If the architecture definition is wrong, i.e., it just misses a 'select
> HAVE_PATA_PLATFORM', then even an expert that configures the kernel build
> should not just fix that by overruling the claimed support by an
> architecture. If the architecture definition is wrong, the expert should
> just provide a patch to correct the architecture definition instead---in
> the end, if the user is an expert, sending a quick one-line patch should
> not be an issue.
>
> In other words, I do not see the deeper why an expert can overrule the
> architecture definition in this case, as the expert may not overrule the
> config selections defined by the architecture in the large majority
> ---or probably all other (modulo some mistakes)---of similar cases.
>
> Signed-off-by: Lukas Bulwahn <lukas.bulwahn@xxxxxxxxx>

Sounds reasonable. My best guess about the intention of the EXPERT
dependency is that it would be used for users with third-party
board files or dts files referencing these. We can't really help
users with out-of-tree boardfiles, and the external dts case would
be covered by your patch 1/2.

Reviewed-by: Arnd Bergmann <arnd@xxxxxxxx>