[PATCH v3 0/4] drm/mxsfb: Fix runtime PM for unpowering lcdif block

[Leonard Crestez <leonard.crestez@nxp.com>]

Adding lcdif nodes to a power domain currently does work, it results in
black/corrupted screens or hangs. While the driver does enable runtime
pm it does not deal correctly with the block being unpowered.

Changes since v2:
 * Split into multiple commits.
 * Use #ifdef CONFIG_PM_SLEEP.
 * Switch to drm_atomic_helper_commit_tail_rpm

Patch 1 was split because it's useful alone.

Patches 2/3 could maybe be squashed.

I'm not sure patch 4 handles vblanks correctly. It does not replace
patch 1 because there is still a small window between enabling the pipe
and the first atomic_update and also somebody needs to write to
NEXT_BUF.

Link to v2: https://lkml.org/lkml/2018/7/17/414

 drivers/gpu/drm/mxsfb/mxsfb_crtc.c | 42 +++++++++++++++++++++---------
 drivers/gpu/drm/mxsfb/mxsfb_drv.c  | 40 ++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+), 13 deletions(-)

-- 
2.17.1