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SubjectRe: [PATCH 1/2] pinctrl: palmas: do not abort pin configuration for BIAS_DEFAULT
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On Fri, Sep 27, 2013 at 6:06 PM, Stephen Warren <swarren@wwwdotorg.org> wrote:
> [Laxman]
>> Hmm.. When I added the PIN_DEFAULT, I just though that do not update
>> anything in the register and implemented like that.
>> There is nothing "default" option in HW.
>
> The description of that pinconfig option is:
>
>> 7970cb77 (Heiko Stübner 2013-06-06 16:44:25 +0200 43) * @PIN_CONFIG_BIAS_PULL_PIN_DEFAULT: the pin will be pulled up or down based
>> 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 44) * on embedded knowledge of the controller hardware, like current mux
>> 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 45) * function. The pull direction and possibly strength too will normally
>> 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 46) * be decided completely inside the hardware block and not be readable
>> 70637a6d (Heiko Stübner 2013-06-25 14:55:42 +0200 47) * from the kernel side.
>> 5ca3353b (Linus Walleij 2013-06-16 12:43:06 +0200 48) * If the argument is != 0 pull up/down is enabled, if it is 0, the
>> 5ca3353b (Linus Walleij 2013-06-16 12:43:06 +0200 49) * configuration is ignored. The proper way to disable it is to use
>> 5ca3353b (Linus Walleij 2013-06-16 12:43:06 +0200 50) * @PIN_CONFIG_BIAS_DISABLE.
>
> If the HW doesn't support any concept of a default pull, I think the
> driver shouldn't support that option; it should return an error if asked
> to program it.

Yes that's how I remember it and how we specified it.
Correct Heiko?

> Presumably given this, LinusW shouldn't have actually applied this
> patch, since presumably it prevents any other driver from accepting
> PIN_CONFIG_BIAS_DISABLE even in cases where it is appropriate?

There are many patches I shouldn't have applied ...

Anyway I'm not quite following, this patch affected the Palmas
driver only I think so how can it prevent any other drivers from doing
the right thing?

We'll just have to follow up with a patch that return -EINVAL for
PIN_CONFIG_BIAS_DISABLE I guess, Laxman is this what you're
doing now?

Yours,
Linus Walleij
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