[PATCH] GPIOLIB: add generic gpio_set_pull API

[Linus Walleij]

On Wed, Jun 20, 2012 at 4:31 PM, Paul Mundt <lethal at linux-sh.org> wrote:
> On Wed, Jun 20, 2012 at 10:15:01AM +0200, Linus Walleij wrote:
>> On Tue, Jun 19, 2012 at 5:25 AM, Barry Song <21cnbao at gmail.com> wrote:
>> > but i think at least the macros of GPIO_PULL_NONE, GPIO_PULL_UP and
>> > GPIO_PULL_DOWN should be standardized.
>>
>> You find an attempt at standardization in drivers/pinctrl/pinconf-generic.c
>> which is also used by the composite U300+COH901 drivers. Drivers
>> can select this support library and use the flags from
>> <linux/pinctrl/pinconf-generic.h>
>>
> What's with PIN_CONFIG_END using such an insane value?

This: PIN_CONFIG_END = 0x7FFF

It's just that I reserved 16 bits for the different stuff, and then
the bitstuffing
functions below use 16 bits for this. If it's too much we can shrink
it.

> I'm happy to consolidate on the provided definitions and add my own on top
> of that, but I'm not going to waste an insane amount of bits that I could
> be using for driver-specific data and so on instead to comply with the
> PIN_CONFIG_END comment. Is there any valid reason why this would ever
> need to exceed 4 bits?

I think we need more than 4 bits for sure, but not more than 8.

If you want to patch it down to have 8 bits for the param and 24 bits
for the argument, go ahead, it won't hurt.

Yours,
Linus Walleij