Commit f618ebfc authored Oct 15, 2008 by Wolfgang Ocker Committed by Kumar Gala Oct 20, 2008

of/spi: Support specifying chip select as active high via device tree



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

Signed-off-by: Wolfgang Ocker <weo@reccoware.de>
Signed-off-by: Kumar Gala <galak@kernel.crashing.org>

parent fd657efc

Documentation/powerpc/booting-without-of.txt

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -1917,6 +1917,8 @@ platforms are moved over to use the flattened-device-tree model.
	inverse clock polarity (CPOL) mode		inverse clock polarity (CPOL) mode
	- spi-cpha - (optional) Empty property indicating device requires		- spi-cpha - (optional) Empty property indicating device requires
	shifted clock phase (CPHA) mode		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 example for an MPC5200 SPI bus:
	spi@f00 {		spi@f00 {

drivers/of/of_spi.c

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -61,6 +61,8 @@ void of_register_spi_devices(struct spi_master master, struct device_node np)
	spi->mode \|= SPI_CPHA;		spi->mode \|= SPI_CPHA;
	if (of_find_property(nc, "spi-cpol", NULL))		if (of_find_property(nc, "spi-cpol", NULL))
	spi->mode \|= SPI_CPOL;		spi->mode \|= SPI_CPOL;
			if (of_find_property(nc, "spi-cs-high", NULL))
			spi->mode \|= SPI_CS_HIGH;

	/* Device speed */		/* Device speed */
	prop = of_get_property(nc, "spi-max-frequency", &len);		prop = of_get_property(nc, "spi-max-frequency", &len);