Re: [PATCH] mfd: syscon: Use of_io_request_and_map() for IO mapping

[Arnd Bergmann]

On Thu, Mar 30, 2023, at 15:22, Loic Poulain wrote:
> On Thu, 30 Mar 2023 at 14:45, Arnd Bergmann <arnd@xxxxxxxx> wrote:
>> On Thu, Mar 30, 2023, at 13:42, Lee Jones wrote:
>> > On Mon, 20 Mar 2023, Loic Poulain wrote:
>>
>> Thanks for pinging me. I would indeed expect this to cause
>> problems, as syscon mappings are likely to be used in a way
>> that is not entirely clean, with other devices defining
>> overlapping ranges.
>
> Isn't syscon exactly here to address that collision/overlapping issue?
> From a syscon perspective, it seems to be handled correctly at least
> since the mapping is only setup once, with the first user device (in
> syscon_node_to_regmap). Or are you thinking about non syscon devices
> overlapping the syscon area?

I meant them overlapping with other devices. Ideally this should
not exist, but most likely we have to deal with dtb files where
some other device does overlap with a syscon.

     Arnd