tree 8ec807be43adf3b5c9f66a2701b7bf0ea3a4a11f
parent bd72a470b9b58386b52ca4568313be71b4d2c472
author Nico Huber <nico.h@gmx.de> 1704476681 +0100
committer Nico Huber <nico.h@gmx.de> 1721642927 +0000

spi: Prepare for multi i/o and dummy bytes

Multi-i/o commands split SPI transactions into multiple phases that
can be transferred over 1, 2 or 4 wires. For this, we adapt `struct
spi_command` with a new enum, specifying the transfer mode, and ad-
ditional size fields.  While we are at it, move everything related
into a new header file `spi_command.h` so we won't further clutter
`flash.h`.

On the master side, we add respective feature flags for the multi-
i/o modes.

See also the comment in `spi_command.h` about multi-i/o commands.

Change-Id: I79debb845f1c8fec77e0556853ffb01735e73ab8
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.sourcearcade.org/c/flashprog/+/44
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>