Re: [RFC/RFT PATCH] gpiolib: reverse-assign the fwnode to struct gpio_chip

From: Andy Shevchenko
Date: Fri Oct 06 2023 - 09:24:13 EST


On Fri, Oct 06, 2023 at 01:51:47PM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
>
> struct gpio_chip is not only used to carry the information needed to
> set-up a GPIO device but is also used in all GPIOLIB callbacks and is
> passed to the matching functions of lookup helpers.
>
> In that last case, it is currently impossible to match a GPIO device by
> fwnode unless it was explicitly assigned to the chip in the provider
> code. If the fwnode is taken from the parent device, the pointer in
> struct gpio_chip will remain NULL.
>
> If we have a parent device but gc->fwnode was not assigned by the
> provider, let's assign it ourselves so that lookup by fwnode can work in
> all cases.

...

> + gc->fwnode = parent_fwnode;

Ah, this is basically reverts my commit, the whole idea of which was to go
towards constant struct gpio_chip object that is supplied by a provider.

--
With Best Regards,
Andy Shevchenko