[PATCH 01/16] pwm: samsung: Update DT bindings documentation to cover clocks
Tomasz Figa
tomasz.figa at gmail.com
Tue Aug 20 18:32:06 EDT 2013
On Tuesday 20 of August 2013 14:34:30 Stephen Warren wrote:
> On 08/20/2013 11:31 AM, Tomasz Figa wrote:
> > PWM driver consumes at least one and up to three clocks, which need to
> > be specified in device tree when used. This patch updates bindings
> > documentation to add information about clocks.
> >
> > diff --git a/Documentation/devicetree/bindings/pwm/pwm-samsung.txt
> > b/Documentation/devicetree/bindings/pwm/pwm-samsung.txt
> >
> > +- clock-names: should contain all following required clock names:
> > + - "timers" - PWM base clock used to generate PWM signals,
> > + and any subset of following optional clock names:
> > + - "pwm-tclk0" - first external PWM clock source,
> > + - "pwm-tclk1" - second external PWM clock source.
> > + Note that not all IP variants allow using all external clock
> > sources. + Refer to SoC documentation to learn which clock source
> > configurations + are available.
>
> It might be nice to explicitly enumerate which variants (or rather, I
> suppose which exact compatible values) support which optional clocks.
> However, I suppose it's fine to just say "go read the HW manual"
> instead.
I don't have enough information about some of the variants, so I decided
to put it this way, instead of making an incomplete list or speculating
about things.
> So, this patch,
> Acked-by: Stephen Warren <swarren at nvidia.com>
Thanks.
> (although this patch isn't backwards-compatible since before now, DT
> nodes didn't need to provide any entries in clocks)
The thing is that the clocks were supposed to be there from the beginning,
but in a hurry I forgot to specify them in original bindings documentation
and things were running over compatibility clkdev aliases anyway, so
nobody (including me) noticed.
Best regards,
Tomasz
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