Re: gpio-omap: add support gpiolib bias (pull-up/down) flags?

[Linus Walleij <linus.walleij@xxxxxxxxxx>]

On Thu, Apr 16, 2020 at 4:17 PM Grygorii Strashko
<grygorii.strashko@xxxxxx> wrote:

> (Changing MUX_MODE from user space sounds very unsafe for me.)

The way it works on a lot of platforms is to implement the
gpio_request_enable() callback such that it muxes the pin
when requested to use as GPIO.

How to handle that is up to the driver, but the simple ones
just assume that if (A) the pin is not muxed for something
else like SPI or MMC or whatever and (B) the pin can be
muxed into GPIO mode, then it goes ahead and does that.

But this policy is up to the driver maintainer.

Given that Beagles etc are pretty much for makers and
industrial control and such, a relaxed policy would be
beneficial for users that want to do some tinkerytink.
The reverse goes for users making airplane control
systems.

Yours,
Linus Walleij