Hi Linus, On Wed, Mar 29, 2017 at 12:15 PM, Linus Walleij <linus.walleij@xxxxxxxxxx> wrote: > On Wed, Mar 29, 2017 at 9:35 AM, Geert Uytterhoeven > <geert@xxxxxxxxxxxxxx> wrote: >>> See for example: >>> include/dt-bindings/pinctrl/mt65xx.h >>> >>> And how that is used in: >>> arch/arm/boot/dts/mt2701-pinfunc.h >>> arch/arm/boot/dts/mt2701-evb.dts >>> >>> The docs are here: >>> Documentation/devicetree/bindings/pinctrl/pinctrl-mt65xx.txt >> >> All of the above pack the information for a pin into a single 32-bit integer. >> Is that what you want us to use, too? >> Currently we use two integers: 1) pin index, and 2) function/flags combo. > > I don't really know what you need, sorry. But some kind of figure, yes. > I would say whatever makes sense. 16+16 bits makes sense in most > combinatorial spaces does it not? If you split 32 bits in 16 bits for > pin and 16 bits for function, do you have more than 2^16 pins or 2^16 > functions? > > If you really do we may need to go for u64 but ... really? Is there > a rational reason for that other than "we did it like this first"? > > I do not understand the notion of "flags" here. I hope that is not referring Flags refers to BI_DIR, SWIO_IN, and SWIO_OUT, from https://patchwork.kernel.org/patch/9643047/ 32-bit should be enough to cover pins, function, and flags. > to pin config, because I expect that to use the standard pin config > bindings outside of the pinmux value which should just define the > pin+function combo: > > node { > pinmux = <PIN_NUMBER_PINMUX>; > GENERIC_PINCONFIG; > }; > > Example from Mediatek: > > i2c1_pins_a: i2c1@0 { > pins { > pinmux = <MT8135_PIN_195_SDA1__FUNC_SDA1>, > <MT8135_PIN_196_SCL1__FUNC_SCL1>; If we follow this example, then we can list all combinations in include/dt-bindings/pinctrl/r7s72100-pinctrl.h, instead of creating the value by combining the bits using a macro where we need it in the DTS. It's gonna be a long list, though... > bias-pull-up = <55>; > }; > }; > > So this allows for a combine pin+function number but pull ups, > bias etc are not baked into the thing, they have to be added on > separately with the generic bindings, which is nice and very readable. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
