Apollolake: Enter/exit from S0ix based on host commands from kernel

This patch changes the entry/exit model for S0ix from a PCH
SLP_S0 signal based model to a hybrid host event/direct interrupt
model. The kernel will send host events on kernel freeze/thaw exit;
EC will initiate the S0ix entry based on host command and exit via
another host command from kernel.

The assertion of SLP_S0 comes later than HC(suspend) and deasserion
of SLP_S0 comes earlier than HC(resume).
        ________                        ________
SLP_S0          |______________________|
        _____                             ________
HC           |___________________________|

BRANCH=none
BUG=chrome-os-partner:58740
TEST=Build/flash EC and check 'echo freeze > /sys/power/state'
command in OS shell. Verify idle state transitions during display off
and periodic wakes from S0ix do not lead to state transitions in EC.

Change-Id: Ie18c6c2ac8998f59141641567d1d740cd72c2d2e
Signed-off-by: Kyoung Kim <kyoung.il.kim@intel.com>
Signed-off-by: Subramony Sesha <subramony.sesha@intel.com>
Signed-off-by: Divagar Mohandass <divagar.mohandass@intel.com>
Signed-off-by: Archana Patni <archana.patni@intel.com>
Reviewed-on: https://chromium-review.googlesource.com/401072
Commit-Ready: Vijay P Hiremath <vijay.p.hiremath@intel.com>
Tested-by: Vijay P Hiremath <vijay.p.hiremath@intel.com>
Reviewed-by: Shawn N <shawnn@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@chromium.org>

0 files changed, 0 insertions, 0 deletions