Some SoCs in the mpc83xx family, e.g. mpc8309, have a dedicated spi
chip select, SPISEL_BOOT, that is used by the boot code to boot from
flash.
This chip select will typically be used to select a SPI boot
flash. The SPISEL_BOOT signal is controlled by a single bit in the
SPI_CS register.
Implement a gpio driver for the spi chip select register. This allows a
spi driver capable of using gpios as chip select, to bind a chip select
to SPISEL_BOOT.
It may be a little odd to do this as a GPIO driver, since the signal
is neither GP or I, but it is quite convenient to present it to the
spi driver that way. The alternative it to teach mpc8xxx_spi to handle
the SPISEL_BOOT signal itself (that is how it's done in the linux
kernel, see commit 69b921acae8a)
Signed-off-by: Klaus H. Sorensen <khso@prevas.dk>
Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Device Tree Bindings Staging Area
=================================
This directory contains device tree bindings for U-Boot.
These follow along with Linux kernel bindings, with a few additions. By
adding the files here, U-Boot patches can clearly show thees additions.
This makes it easier for device tree people to review these additions in
patches sent to the U-Boot mailing list.
The intent IS to commit these files to U-Boot. Hopefully at some point
the files will be stored in another repo (shared with Linux) which is
brought in as needed. Changes here are intended to mirror changes in the
Linux Documentation/devicetree/bindings/ directory.
sjg@chromium.org
17-Jan-12
3fb22bc2f8