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

Wolfgang Ocker weo at reccoware.de
Thu Oct 16 00:00:47 EST 2008


The patch allows to specify that an SPI device needs an active high chip
select.

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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