Re: pinctrl-single: num_maps in generic pinconf support?

[Tony Lindgren <tony@atomide.com>]

* Drew Fustini <drew@beagleboard.org> [200528 12:54]:
> Would you be able to describe what you think AM33XX_PADCONF would look
> like if the mux and conf are seperated?

Yes it would just slightly change, see your example below.

> Is there an example you know of for another SoC?

I think the other driver already keep the padconf and mux separate.

So not sure where all #pinctrl-cells could be used. It would make
pinctrl-single.c a bit nicer though, and probably would make it
easier to implement further features.

Some hardware may need it to have #pinctrl-cells = <3> if GPIO
features are there too, ideally pinctrl-single would not even
care but just work for what is configured for the hardware.

> Currently, the macro takes dir and mux:
> 
> include/dt-bindings/pinctrl/omap.h:
> #define AM33XX_PADCONF(pa, dir, mux) OMAP_IOPAD_OFFSET((pa), 0x0800) ((dir) | (mux))

So after fixing up pinctrl-single.c, and changing the SoC dts
to have #pinctrl-cells = <2> instead of <1>, the macro would
then need to be:

#define AM33XX_PADCONF(pa, dir, mux) OMAP_IOPAD_OFFSET((pa), 0x0800) (dir), (mux))

> For example, in arch/arm/boot/dts/am335x-bone-common.dtsi:
> AM33XX_PADCONF(AM335X_PIN_I2C0_SDA, PIN_INPUT_PULLUP, MUX_MODE0)

Yeah so no change needed for the use.

> I think it might be more accurate to rename 'dir' to 'conf'.

Sure makes sense to rename it in the macro.

Regards,

Tony