Hi Boris,
On Fri, Mar 23, 2018 at 12:00 PM, Boris Brezillon
<boris.brezillon@xxxxxxxxxxx> wrote:
> Document the Cadence I3C gpio expander bindings.
>
> Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxx>
Thanks for your patch!
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/gpio-cdns-i3c.txt
> @@ -0,0 +1,38 @@
> +* Cadence I3C GPIO expander
> +
> +The Cadence I3C GPIO expander provides 8 GPIOs controllable over I3C.
> +This GPIOs can be configured in output or input mode and if they are in input
> +mode they can generate IBIs (In Band Interrupts).
> +
> +Required properties for GPIO node:
> +- reg : 3 cells encoding the I3C static address (none in our case) and the I3C
> + Provisional ID. See Documentation/devicetree/bindings/i3c/i3c.txt for
> + more details.
> + Should be <0x0 0x392 0x0>.
No compatible value?
> +- gpio-controller : Marks the device node as a gpio controller.
> +- #gpio-cells : Should be two. The first cell is the pin number and
> + the second cell is used to specify the gpio polarity:
> + 0 = active high
> + 1 = active low
> +- interrupt-controller: Marks the device node as an interrupt controller.
> +- #interrupt-cells : Should be 2. The first cell is the GPIO number.
> + The second cell bits[3:0] is used to specify trigger type and level flags:
> + 1 = low-to-high edge triggered.
> + 2 = high-to-low edge triggered.
> + 3 = triggered on both edges.
> + 4 = active high level-sensitive.
> + 8 = active low level-sensitive.
> +
> +Example:
> +
> + i3c-master@xxx {
> + ...
> + i3c_gpio_expander: gpio@0,1c9,0 {
gpio@0,392,0?
> + reg = <0 0x392 0x0>;
> + gpio-controller;
> + #gpio-cells = <2>;
> + interrupt-controller;
> + #interrupt-cells = <2>;
> + };
> + ...
> + };
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
