With this commit we can modify single values within an array of a dts
This is useful if we have for example a pwm-backlight where we want to
modifiy the pwm frequency per u-boot script.
The pwm is described in dts like this:
pwms = <0x0000002b 0x00000000 0x004c4b40>;
For changing the frequency, here the 3rd parameter, we simply type:
fdt set /backlight pwms <? ? 0x1E8480>;
For doing all this we:
- backup the property content into our 'SCRATCHPAD'
- only modify the array-cell if the new content doesn't start with '?'
Signed-off-by: Hannes Schmelzer <firstname.lastname@example.org>
Reviewed-by: Simon Glass <email@example.com>