Add a SPI command class to `struct flashchip`

This is a backport of `commit 31b5e3bf` upstream;

By default, we want to probe for SPI25 chips only. Other SPI use cases,
like the ENE/EDI protocol, might use commands that can confuse these
common chips.

Now, flashrom will probe for a chip only if one of these conditions is
true:
1) no chip has been specified AND the chip uses the SPI25 commands
2) this chip has been specified by -c | --chip <chipname>

The CLI can later be extended to probe for a specific class of chips.

Signed-off-by: Mike Banon <mikebdp2@gmail.com>
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/23262
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Kocialkowski <contact@paulk.fr>

BUG=chromium:478356
BRANCH=none
TEST=still builds

Change-Id: I9e1943311a8a9f9427cc0cff6e2762c966a7ad84
Signed-off-by: Edward O'Callaghan <quasisec@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1484920
Reviewed-by: Patrick Georgi <pgeorgi@chromium.org>
Reviewed-by: Stefan Reinauer <reinauer@chromium.org>
2 files changed