On Tue, Jun 13, 2017 at 4:39 AM, Zhang Bo [off-list ref] wrote:

This reverts commit 5ab92a7cb82c66bf30685583a38a18538e3807db.

System cannot enter suspend mode because of heartbeat led trigger.
In autosleep_wq, try_to_suspend function will try to enter suspend
mode in specific period. it will get wakeup_count then call pm_notifier
chain callback function and freeze processes.
Heartbeat_pm_notifier is called and it call led_trigger_unregister to
change the trigger of led device to none. It will send uevent message
and the wakeup source count changed. As wakeup_count changed, suspend
will abort.

Signed-off-by: Zhang Bo <redacted>

OK I was stupid, lesson learned.
Reviewed-by: Linus Walleij <redacted>

Yours,
Linus Walleij