[PATCH] powerpc: SPI: specify chip select active high

Grant Likely grant.likely at secretlab.ca
Thu Oct 16 01:22:28 EST 2008


On Wed, Oct 15, 2008 at 03:00:47PM +0200, Wolfgang Ocker wrote:
> The patch allows to specify that an SPI device needs an active high chip
> select.

This look reasonable to me.  Anyone else have comments on this binding?

g.

> 
> Signed-off-by: Wolfgang Ocker <weo at reccoware.de>
> ---
> 
> --- linux-2.6.27-rc7/drivers/of/of_spi.c.of_spi_cshigh	2008-09-22 00:29:55.000000000 +0200
> +++ linux-2.6.27-rc7/drivers/of/of_spi.c	2008-09-29 13:43:06.000000000 +0200
> @@ -61,6 +61,8 @@
>  			spi->mode |= SPI_CPHA;
>  		if (of_find_property(nc, "spi-cpol", NULL))
>  			spi->mode |= SPI_CPOL;
> +		if (of_find_property(nc, "spi-cs-high", NULL))
> +			spi->mode |= SPI_CS_HIGH;
>  
>  		/* Device speed */
>  		prop = of_get_property(nc, "spi-max-frequency", &len);
> --- linux-2.6.27-rc7/Documentation/powerpc/booting-without-of.txt.of_spi_cshigh	2008-09-29 14:14:08.000000000 +0200
> +++ linux-2.6.27-rc7/Documentation/powerpc/booting-without-of.txt	2008-09-29 14:24:26.000000000 +0200
> @@ -1917,6 +1917,8 @@
>  			inverse clock polarity (CPOL) mode
>      - spi-cpha        - (optional) Empty property indicating device requires
>  			shifted clock phase (CPHA) mode
> +    - spi-cs-high     - (optional) Empty property indicating device requires
> +			chip select active high
>  
>      SPI example for an MPC5200 SPI bus:
>  		spi at f00 {
> 
> 
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