Commit graph

2 commits

Author SHA1 Message Date
Rasmus Villemoes
24e8c0e3b3 gpio/mpc83xx_spisel_boot.c: include log.h
Fix build failure, it used to get this implicitly through common.h
until f7ae49fc4f (common: Drop log.h from common header).

Signed-off-by: Rasmus Villemoes <rasmus.villemoes@prevas.dk>
Reviewed-by: Heiko Schocher <hs@denx.de>
2020-09-22 11:05:32 -04:00
Klaus H. Sorensen
3fb22bc2f8 gpio/mpc83xx_spisel_boot.c: gpio driver for SPISEL_BOOT signal
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>
2020-03-31 10:06:52 -04:00