Re: [PATCH v3 1/1] pinctrl: add Intel BayTrail GPIO/pinctrl support

[Mathias Nyman <mathias.nyman@linux.intel.com>]

On 04/12/2014 01:54 AM, Timur Tabi wrote:
> On Tue, Jun 18, 2013 at 6:33 AM, Mathias Nyman
> <mathias.nyman@linux.intel.com> wrote:
>>
>> Pins may be muxed to alternate function instead of gpio by firmware.
>> This driver does not touch the pin muxing and expect firmare
>> to set pin muxing and pullup/down properties properly.
>>
>> Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
>> ---
>>   drivers/pinctrl/Kconfig            |   12 +
>>   drivers/pinctrl/Makefile           |    1 +
>>   drivers/pinctrl/pinctrl-baytrail.c |  543 ++++++++++++++++++++++++++++++++++++
>
>
> I know it's been ten months since you posted this driver, but I have a
> question.  If this driver does not touch the pin muxing, and it
> doesn't even call pinctrl_register(), then why is it in
> drivers/pinctrl?  It's not a pinctrl driver.  Why isn't this a regular
> GPIO drivers in drivers/gpio?
>

This was the conclusion we reached after some discussion with Linus W.
Initially this was just a GPIO driver, but Linus correctly spotted that 
Baytrail has many pinctrl-like features (like pin muxing, etc) that we 
might need to address in the future.

threads where this was discussed:

http://marc.info/?l=linux-kernel&m=136994203308585&w=2
http://marc.info/?l=linux-kernel&m=137113578604763&w=2

-Mathias