• Prasad Sodagudi's avatar
    PM: sleep: core: Avoid setting power.must_resume to false · 4a9344cd
    Prasad Sodagudi authored
    There are variables(power.may_skip_resume and dev->power.must_resume)
    and DPM_FLAG_MAY_SKIP_RESUME flags to control the resume of devices after
    a system wide suspend transition.
    
    Setting the DPM_FLAG_MAY_SKIP_RESUME flag means that the driver allows
    its "noirq" and "early" resume callbacks to be skipped if the device
    can be left in suspend after a system-wide transition into the working
    state. PM core determines that the driver's "noirq" and "early" resume
    callbacks should be skipped or not with dev_pm_skip_resume() function by
    checking power.may_skip_resume variable.
    
    power.must_resume variable is getting set to false in __device_suspend()
    function without checking device's DPM_FLAG_MAY_SKIP_RESUME settings.
    In problematic scenario, where all the devices in the suspend_late
    stage are successful and some device can fail to suspend in
    suspend_noirq phase. So some devices successfully suspended in suspend_late
    stage are not getting chance to execute __device_suspend_noirq()
    to set dev->power.must_resume variable to true and not getting
    resumed in early_resume phase.
    
    Add a check for device's DPM_FLAG_MAY_SKIP_RESUME flag before
    setting power.must_resume variable in __device_suspend function.
    
    Fixes: 6e176bf8 ("PM: sleep: core: Do not skip callbacks in the resume phase")
    Signed-off-by: default avatarPrasad Sodagudi <psodagud@codeaurora.org>
    Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
    4a9344cd
main.c 49.9 KB