Re: [PATCH v9 1/1] gpio: mpfs: add polarfire soc gpio support

[Bartosz Golaszewski <brgl@xxxxxxxx>]

On Fri, Nov 1, 2024 at 2:37 PM Conor Dooley <conor@xxxxxxxxxx> wrote:
>
> On Fri, Nov 01, 2024 at 02:09:06PM +0100, Bartosz Golaszewski wrote:
> > On Fri, Nov 1, 2024 at 1:17 PM Conor Dooley <conor@xxxxxxxxxx> wrote:
> > >
> > > On Thu, Oct 31, 2024 at 02:00:22PM +0100, Bartosz Golaszewski wrote:
> > > > On Thu, Oct 31, 2024 at 1:04 PM Conor Dooley <conor@xxxxxxxxxx> wrote:
> > >
> > > > > +       mpfs_gpio->gc.direction_input = mpfs_gpio_direction_input;
> > > > > +       mpfs_gpio->gc.direction_output = mpfs_gpio_direction_output;
> > > > > +       mpfs_gpio->gc.get_direction = mpfs_gpio_get_direction;
> > > > > +       mpfs_gpio->gc.get = mpfs_gpio_get;
> > > > > +       mpfs_gpio->gc.set = mpfs_gpio_set;
> > > > > +       mpfs_gpio->gc.base = -1;
> > > > > +       mpfs_gpio->gc.ngpio = ngpios;
> > > >
> > > > The "ngpios" property will be parsed by GPIO core so no need to set it.
> > >
> > > Are you sure it'll work here? I tried dropping the ngpios parsing, but I
> > > get:
> > > gpiochip_add_data_with_key: GPIOs 0..-1 (20122000.gpio) failed to register, -22
> > >
> > > That's coming from the device_property_read_u32(dev, "ngpios", &ngpios);
> > > in gpiochip_get_ngpios(). Checking against the bluefield driver and the
> > > code in gpiochip_add_data_with_key(), it's not immediately obvious what
> > > I am missing.
> >
> > Does dev have an fwnode correctly assigned? What does dev_fwnode(dev) return?
>
> It's not a null pointer or something obviously wrong by virtue of being
> null-adjacent, it is a virtual address but not one that %ps can identify.

This is an OF system right? If you do dev_of_node(dev), does the
returned node->name show the OF node you expect? Does it have the
"ngpios" property? Can you read it with of_property_read_u32()?

Bart