Re: [PATCH 1/2] dt-bindings: reset: Add generic GPIO reset binding

[Sean Anderson]

(I forgot to finish my thought)

On 10/28/21 11:19 AM, Sean Anderson wrote:
> Hi Rob,
>
> On 10/26/21 10:27 PM, Rob Herring wrote:
> > On Mon, Oct 18, 2021 at 07:49:21PM -0400, Sean Anderson wrote:
> > > This adds a binding for a generic GPIO reset driver. This driver is
> > > designed to easily add a GPIO-based reset to a driver which expected a
> > > reset controller. It offers greater flexibility than a reset-gpios
> > > property, and allows for one code path to be shared for GPIO resets and
> > > MMIO-based resets.
> >
> > I would like to do this last part, but not requiring a binding change.
> > IOW, be able to register any 'reset-gpios' property as a reset provider
> > directly without this added level of indirection.
>
> That would be nice, but it seems like someone would have to go through
> every driver with a reset-gpios property and convert them. Since the
> reset GPIOs are
...effectively ad-hoc, I think it would be difficult to do a conversion
in a generic manner (especially since some devices will fail to probe if
they don't get control of the GPIOs). Maybe this could be done with a
single reset driver which has reset GPIOs added to it dynamically? E.g.
when a driver requests a reset named "some-name" and there is a
reset-gpios property, request the GPIOs and assign them to the reset
driver, then hand that reset back to the calling driver.

On the other hand, having a separate driver like this makes it easy to
incrementally convert existing drivers. Although it does require a
change in bindings.

--Sean