Re: [PATCH 12/18] gpio: add support for the sl28cpld GPIO controller

[Michael Walle]

Am 2020-03-27 11:20, schrieb Linus Walleij:
> On Thu, Mar 26, 2020 at 9:06 PM Michael Walle <michael@xxxxxxxx> wrote:
> > Am 2020-03-25 12:50, schrieb Bartosz Golaszewski:
>
> > > In that case maybe you should use the disable_locking option in
> > > regmap_config and provide your own callbacks that you can use in the
> > > irqchip code too?
> >
> > But how would that solve problem (1). And keep in mind, that the
> > reqmap_irqchip is actually used for the interrupt controller, which
> > is not this gpio controller.
> >
> > Ie. the interrupt controller of the sl28cpld uses the regmap_irqchip
> > and all interrupt phandles pointing to the interrupt controller will
> > reference the toplevel node. Any phandles pointing to the gpio
> > controller will reference the GPIO subnode.
>
> Ideally we would create something generic that has been on my
> mind for some time, like a generic GPIO regmap irqchip now that
> there are a few controllers like that.
>
> I don't know how feasible it is or how much work it would be. But
> as with GPIO_GENERIC (for MMIO) it would be helpful since we
> can then implement things like .set_multiple() and .get_multiple()
> for everyone.

For starters, would that be a drivers/gpio/gpio-regmap.c or a
drivers/base/regmap/regmap-gpio.c? I would assume the first,
because the stuff in drivers/base/regmap operates on a given
regmap and we'd just be using one, correct? On the other hand
there is also the reqmap-irq.c. But as pointed out before, it
will add an interrupt controller to the regmap, not a device
so to speak.

-michael