FROMGIT: spi: spi-mtk-nor: Add power management support

This patch adds dev_pm_ops to mtk-nor to support suspend/resume,
auto suspend delay is set to -1 by default.

Accessing registers are only permitted after its clock is enabled
to deal with unknown state of operating clk at probe time.

Signed-off-by: Ikjoon Jang <ikjn@chromium.org>
Link: https://lore.kernel.org/r/20201006155010.v5.4.I68983b582d949a91866163bab588ff3c2a0d0275@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>
(cherry picked from commit 3bfd9103c7af07915a84a6849e718622936233c1
 git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git for-next)

BUG=b:157602285
TEST=check status on {auto|system} suspend, resume

Change-Id: Ia3173acc463137e059d47ec2eaa0a2dfdc82b76e
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/2467563
Reviewed-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-by: Sean Paul <seanpaul@chromium.org>
Commit-Queue: Ikjoon Jang <ikjn@chromium.org>
Tested-by: Ikjoon Jang <ikjn@chromium.org>
1 file changed