mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-07 13:44:29 +00:00
3fb22bc2f8
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>
22 lines
598 B
Text
22 lines
598 B
Text
MPC83xx SPISEL_BOOT gpio controller
|
|
|
|
Provide access to MPC83xx SPISEL_BOOT signal as a gpio to allow it to be
|
|
easily bound as a SPI controller chip select.
|
|
|
|
The SPISEL_BOOT signal is always an output.
|
|
|
|
Required properties:
|
|
|
|
- compatible: must be "fsl,mpc83xx-spisel-boot" or "fsl,mpc8309-spisel-boot".
|
|
- reg: must point to the SPI_CS register in the SoC register map.
|
|
- ngpios: number of gpios provided by driver, normally 1.
|
|
|
|
Example:
|
|
|
|
spisel_boot: spisel_boot@14c {
|
|
compatible = "fsl,mpc8309-spisel-boot";
|
|
reg = <0x14c 0x04>;
|
|
#gpio-cells = <2>;
|
|
device_type = "gpio";
|
|
ngpios = <1>;
|
|
};
|