Re: [PATCH 09/11] dt-bindings: spi/spi-pxa2xx: Add ready GPIO signal
From: Geert Uytterhoeven
Date: Thu Oct 11 2018 - 03:26:54 EST
On Wed, Oct 10, 2018 at 7:10 PM Lubomir Rintel <lkundrak@xxxxx> wrote:
> This this is used to let the SPI master know that our FIFO is filled and
> we're ready to service a transfer. Only useful in slave mode.
> A signal like this is used by an embedded controller on a OLPC XO 1.75
> machine, that happens to be a SPI master.
> Signed-off-by: Lubomir Rintel <lkundrak@xxxxx>
Thanks for your patch!
> --- a/Documentation/devicetree/bindings/spi/spi-pxa2xx.txt
> +++ b/Documentation/devicetree/bindings/spi/spi-pxa2xx.txt
> @@ -12,6 +12,8 @@ Optional properties:
> - cs-gpios: list of GPIO chip selects. See the SPI bus bindings,
> - spi-slave: Empty property indicating the SPI controller is used in slave mode.
> +- ready-gpio: GPIO used to signal a SPI master that the FIFO is filled
"GPIO properties named "[<name>-]gpio" are valid and old
bindings use it, but are only supported for compatibility reasons
and should not
be used for newer bindings since it has been deprecated."
> + and we're ready to service a transfer. Only useful in slave mode.
> Child nodes represent devices on the SPI bus
> See ../spi/spi-bus.txt
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