[PATCH v2 2/3] pinctrl: Add msm8x74 configuration

Bjorn Andersson bjorn.andersson at sonymobile.com
Thu Dec 12 23:24:17 EST 2013


On Thu 12 Dec 11:15 PST 2013, Linus Walleij wrote:

> On Wed, Dec 11, 2013 at 2:49 AM, Stephen Boyd <sboyd at codeaurora.org> wrote:
...
> > I don't follow what Linus is recommending. How could
> > .gpio_request_enable()/.gpio_disable_free() help us here?
> 
> That removes the need to define a single group for each pin that
> can be used as GPIO.

For the TLMM chip the pin can not be used as GPIO when another function is
selected for the pin. And upon leaving a state with a function defined the
choosen mux is disabled, turning the pin back to a GPIO pin.
So I don't think this is applicable for us, any unused pin is a GPIO pin.


The reason why there are 1 pingroup per pin is because a pingroup represent
a configurable entity, i.e. a config register in the TLMM chip; which is one
per pin for the GPIO pins.

Regards,
Bjorn



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