On Fri, Oct 7, 2016 at 4:56 PM, <ttha...@opensource.altera.com> wrote:
> From: Thor Thayer <ttha...@opensource.altera.com>
>
> Some SPI masters require the slave to be selected before a
> transaction can occur - even in the case of GPIO chip select.
>
> This patch adds a GPIO slave select parameter to indicate
> the slave needs to be selected in the GPIO CS case.
>
> Signed-off-by: Thor Thayer <ttha...@opensource.altera.com>
> ---
> v2 Add to SPI framework - add bindings.
> ---
> Documentation/devicetree/bindings/spi/spi-bus.txt | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/Documentation/devicetree/bindings/spi/spi-bus.txt
> b/Documentation/devicetree/bindings/spi/spi-bus.txt
> index 4b1d6e7..3a006bc 100644
> --- a/Documentation/devicetree/bindings/spi/spi-bus.txt
> +++ b/Documentation/devicetree/bindings/spi/spi-bus.txt
> @@ -24,6 +24,7 @@ support describing the chip select layout.
> Optional properties:
> - cs-gpios - gpios chip select.
> - num-cs - total number of chipselects.
> +- gpio-ss - use internal slave select with gpio chip select.
>
> If cs-gpios is used the number of chip selects will be increased
> automatically
> with max(cs-gpios > hw cs).
To me, this looks more like a new flag the SPI controller driver should
set in spi_master.flags, instead of a DT property.
Gr{oetje,eeting}s,
Geert
--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- ge...@linux-m68k.org
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
