Re: [RFC Patch] gpio: add GPIO hogging mechanism

Linus Walleij
2014-11-03T09:43:52Z

On Wed, Oct 29, 2014 at 9:53 AM, Pantelis Antoniou
<pantelis.antoniou@gmail.com> wrote:

> 3) I’m not very fond of having this being part of the gpio controller. This
> configuration conceptually has little to do with the gpio controller per se,
> it is more of a board specific thing. Why not come up with a gpio-hog driver that
> references GPIOs? That way with a single gpio-hog driver instance you could setup
> all the GPIO-hogging configuration for all GPIOs on the board, even one that
> lie on different GPIO controllers.

You have a point. But it's vital that we set up hogs at the same time as the
gpio_chip is probed, not later, or there may be a race as to who
gets the GPIO line, and that should be avoided at any cost.

Yours,
Linus Walleij