Re: [PATCH 2/3] spi: sh-msiof: Convert to spi core auto_runtime_pm framework

[Magnus Damm <magnus.damm@gmail.com>]

Hi Laurent,

On Wed, Mar 12, 2014 at 8:26 PM, Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
> Hi Magnus,
>
> On Wednesday 12 March 2014 10:23:48 Magnus Damm wrote:
>> On Wed, Mar 12, 2014 at 1:32 AM, Laurent Pinchart wrote:
>> > On Tuesday 11 March 2014 17:23:37 Geert Uytterhoeven wrote:
>> >> Hi Laurent,
>> >>
>> >> On Tue, Mar 11, 2014 at 4:55 PM, Laurent Pinchart wrote:
>> >> > Does this require drivers/sh/pm_runtime.c to be compiled in ?
>> >>
>> >> Let's check...
>> >>
>> >> My koelsch-legacy kernel has drivers/sh/pm_runtime.c compiled in.
>> >> My koelsch-reference kernel hasn't.
>> >>
>> >> However, under the -reference kernel many MSTP clocks (incl. MSIOF)
>> >> seem to be enabled all the time, while under -legacy they are enabled and
>> >> disabled on demand.
>> >
>> > Is PM_RUNTIME enabled in both cases ?
>> >
>> > There's something fishy in there that we should try to fix without too
>> > further much delay. Ben Dooks has pointed out the problem a couple of
>> > months ago, but the discussion on the mailing list just died.
>>
>> Yes, Runtime PM is not working as expected in the multiplatform case,
>> that is true. I propose that we keep Runtime PM disabled in the
>> Kconfig for R-Car Gen2 for now to keep things simple.
>
> Isn't it ? I thought it was only broken with regard to clocks, but I might be
> missing something.

Perhaps the correct way to put it is that we have not yet figured out
how to enable Runtime PM in a way that is suitable for multiplatform.
Which means that clocks are behaving differently in the legacy case
and in the multiplatform case.

Thanks,

/ magnus