Re: MCP23S08 Pincontroller Bias Configuration and GpioLib

[Matt Walker <m@xxxxxxxxxxxx>]

On Thu, Sep 19, 2024 at 12:11 AM Kent Gibson <warthog618@xxxxxxxxx> wrote:
> On Wed, Sep 18, 2024 at 09:21:11PM -0400, Matt Walker wrote:
> > ... I thought the pin controller was solely responsible for
> > configuration of bias and that the gpiolib would magically know that
> > it needs to call pinconf_ops.pin_config_set. Since it seems like an
> > unnecessary duplication of effort to set bias config in both pinctrl
> > and gpiochip, I figure I'm missing something. I thought it might be
> > that the MCP driver does not have an explicit call to
> > gpiochip_add_pin_range, but that wasn't it.
>
> Not my bailiwick, but looking through the code (both gpiolib and drivers)
> it seems to me you should set
>
>         mcp->chip.set_config = gpiochip_generic_config;
>
> to hook into the magic that you are expecting.

Thanks Kent! I think that is the magic, it's even listed plainly in
the documentation that my eyes managed to glaze over. It's not working
as a drop in, but it definitely gives me a string to pull for the
correct way of doing this.