Re: [PATCH v3 2/4] ARM: bcm2835: add rpi power domain driver

[Ulf Hansson <ulf.hansson@linaro.org>]

On 16 December 2015 at 02:27, Krzysztof Kozlowski
<k.kozlowski@samsung.com> wrote:
> 2015-12-16 10:11 GMT+09:00 Sebastian Reichel <sre@ring0.de>:
>> Hi,
>>
>> On Tue, Dec 15, 2015 at 04:53:31PM -0800, Eric Anholt wrote:
>>> >>> What motivated the location of this power domain driver in
>>> >>> arch/arm/mach-bcm? Should not we have this in drivers/power/ or
>>> >>> somewhere in drivers/ at the very least?
>>> >>
>>> >> ls stronly suggests that power contains drivers for power supplies and
>>> >> batteries, not power domains.
>>
>> Indeed it's used for fuel gauges and chargers, but also for
>> reboot/powerdown and adaptive voltage scaling, so another
>> subdirectory for power-domains wouldn't be that odd.
>>
>>> >> There are 6 power domain drivers in
>>> >> arch/arm, 3 in drivers/clk, and 3 in drivers/soc.
>>> >
>>> > If we ever have to support a different architecture which happens to use
>>> > a similar power domain, then we want it to be in a location which makes
>>> > it easy for sharing it in the first place. As it stands today, it does
>>> > not seem useful to me to have this code in arch/arm/mach-bcm/ at all.
>>> >
>>> > Maybe there is room from a drivers/power/domains/ of some kind?
>>
>> I like the idea, but let's include generic power domain maintainers
>> in this discussion, as I suggested here (I got a power domain driver
>> patch for drivers/power just a few days ago):
>>
>> https://lkml.org/lkml/2015/12/15/815
>>
>> Also somebody would have to step up to maintain that directory.
>
> This could go into drivers/soc. We put there a lot of mach-specific
> stuff which we want to make a little more generic (like generic enough
> multiplatform, multiarchitecture etc). Rockchip has its own power
> domains there. Dove and Mediatek seem as well but I am not sure. Some
> other architectures keep this still in arm/mach (exynos, ux500, zx,
> imx, s34c64xx, shmobile) but this looks more of like a legacy choice.

Agree, drivers/soc is good.

>
> However, since the generic power domains have its own maintainers entry
> and reside under drivers/base/power, maybe making a separate directory
> for power domains drivers makes sense?

That could work as well, but I have no strong opinion.
Perhaps it would become a bit more clear, although in that case I
would also move drivers/base/power/domain* in there.

If that happens, I am willing to help maintain it.

Kind regards
Uffe