[PATCH 2/5] ARM: PXA: Zipit Z2: Add USB host and device support

Vasily Khoruzhick anarsoul at gmail.com
Mon Nov 5 12:31:45 EST 2012


On Sat, Nov 3, 2012 at 12:29 AM, Vasily Khoruzhick <anarsoul at gmail.com> wrote:

>>
>> I prefer to use pinctrl-single driver instead. I'm updating mmp
>> pinctrol driver to
>> pinctrl-single driver framework. You can find them in mailist. I'm submitting
>> a third round in these days.
>>
>> Regards
>> Haojian
>
> OK, one more question:
>
> On PXA2xx GPIO and PINMUX are not separate blocks. Each pin can be
> either input or output and have 4 modes (gpio + 3 alternate functions)
> == 8 states , so we have: gpio in, gpio out, 3 alt in, 3 alt out.
> To control pin mode one should write to GPDR (direction register) and
> GAFR (alternate function register). pxa-gpio driver controls both of
> those registers, so does pxa2xx-mfp.
>
> I'm not sure what to do in this case. Should I move code controlling
> GPDR and GAFR into some pinctrl-pxa2xx driver, and modify pxa-gpio
> driver to use it?
>
> Regards
> Vasily

Daniel, Haojian, any suggestion?

I'm stuck at the moment, and have no idea how to handle it...
pinmux/gpio are connected in hardware
and I don't see a way to handle them with 2 separate drivers (gpio and
pinmux) in software...

Regards
Vasily



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