powerpc/of: added documentation for spi chipselects

Added devicetree binding documentation for gpios used as chipselect. The
code to evaluate these is already present in spi_mpc8xxx.c.

Signed-off-by: Ernst Schwab <eschwab@online.de>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
This commit is contained in:
Ernst Schwab 2010-02-17 07:33:02 -07:00 committed by Grant Likely
parent e9cb0a4924
commit 85cd7467f3

View File

@ -13,6 +13,11 @@ Required properties:
- interrupt-parent : the phandle for the interrupt controller that
services interrupts for this device.
Optional properties:
- gpios : specifies the gpio pins to be used for chipselects.
The gpios will be referred to as reg = <index> in the SPI child nodes.
If unspecified, a single SPI device without a chip select can be used.
Example:
spi@4c0 {
cell-index = <0>;
@ -21,4 +26,6 @@ Example:
interrupts = <82 0>;
interrupt-parent = <700>;
mode = "cpu";
gpios = <&gpio 18 1 // device reg=<0>
&gpio 19 1>; // device reg=<1>
};