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Date: Mon, 22 Feb 2016 19:03:44 -0800
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Subject: Re: [PATCH v3 00/12] pwm: add support for atomic update
From: Doug Anderson <dianders@google.com>
To: Mark Brown <broonie@kernel.org>
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Mark,

On Mon, Feb 22, 2016 at 1:24 PM, Mark Brown <broonie@kernel.org> wrote:
> On Mon, Feb 22, 2016 at 11:15:09AM -0800, Doug Anderson wrote:
>
>> Note that historically I remember that Linus Torvalds has stated that
>> there is no stable API within the Linux kernel and that forcing the
>> in-kernel API to never change was bad for software development.  I
>> tracked down my memory and found
>> <http://lwn.net/1999/0211/a/lt-binary.html>.  Linus is rabid about not
>> breaking userspace, but in general there's no strong requirement to
>> never change the driver API inside the kernel.  That being said,
>> changing the driver API causes a lot of churn, so presumably changing
>> it in a backward compatible way (like adding to the API instead of
>> changing it) will make things happier.
>
> You do need to fix the users though, change is fine but you can't cause
> people's systems to break.

Yes, of course!  :)  Thanks for clarifying.

-Doug