kernel/linux.git/drivers/base/power/main.c, branch v4.4.171

PM / core: Clear the direct_complete flag on errors

2018-10-13T07:11:32+00:00

commit 69e445ab8b66a9f30519842ef18be555d3ee9b51 upstream. If __device_suspend() runs asynchronously (in which case the device passed to it is in dpm_suspended_list at that point) and it returns early on an error or pending wakeup, and the power.direct_complete flag has been set for the device already, the subsequent device_resume() will be confused by that and it will call pm_runtime_enable() incorrectly, as runtime PM has not been disabled for the device by __device_suspend(). To avoid that, clear power.direct_complete if __device_suspend() is not going to disable runtime PM for the device before returning. Fixes: aae4518b3124 (PM / sleep: Mechanism to avoid resuming runtime-suspended devices unnecessarily) Reported-by: Al Cooper Tested-by: Al Cooper Reviewed-by: Ulf Hansson Cc: 3.16+ # 3.16+ Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM / sleep: don't suspend parent when async child suspend_{noirq, late} fails

2016-11-26T08:54:53+00:00

commit 6f75c3fd56daf547d684127a7f83c283c3c160d1 upstream. Consider two devices, A and B, where B is a child of A, and B utilizes asynchronous suspend (it does not matter whether A is sync or async). If B fails to suspend_noirq() or suspend_late(), or is interrupted by a wakeup (pm_wakeup_pending()), then it aborts and sets the async_error variable. However, device A does not (immediately) check the async_error variable; it may continue to run its own suspend_noirq()/suspend_late() callback. This is bad. We can resolve this problem by doing our error and wakeup checking (particularly, for the async_error flag) after waiting for children to suspend, instead of before. This also helps align the logic for the noirq and late suspend cases with the logic in __device_suspend(). It's easy to observe this erroneous behavior by, for example, forcing a device to sleep a bit in its suspend_noirq() (to ensure the parent is waiting for the child to complete), then return an error, and watch the parent suspend_noirq() still get called. (Or similarly, fake a wakeup event at the right (or is it wrong?) time.) Fixes: de377b397272 (PM / sleep: Asynchronous threads for suspend_late) Fixes: 28b6fd6e3779 (PM / sleep: Asynchronous threads for suspend_noirq) Reported-by: Jeffy Chen Signed-off-by: Brian Norris Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM / sleep: Handle failures in device_suspend_late() consistently

2016-06-08T01:14:37+00:00

commit 3a17fb329da68cb00558721aff876a80bba2fdb9 upstream. Grygorii Strashko reports: The PM runtime will be left disabled for the device if its .suspend_late() callback fails and async suspend is not allowed for this device. In this case device will not be added in dpm_late_early_list and dpm_resume_early() will ignore this device, as result PM runtime will be disabled for it forever (side effect: after 8 subsequent failures for the same device the PM runtime will be reenabled due to disable_depth overflow). To fix this problem, add devices to dpm_late_early_list regardless of whether or not device_suspend_late() returns errors for them. That will ensure failures in there to be handled consistently for all devices regardless of their async suspend/resume status. Reported-by: Grygorii Strashko Tested-by: Grygorii Strashko Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

PM / sleep: Allow devices without runtime PM to do direct-complete

2015-07-21T21:14:22+00:00

Don't unset the direct_complete flag on devices that have runtime PM disabled, if they are runtime suspended. This is needed because otherwise ancestor devices wouldn't be able to do direct_complete without adding runtime PM support to all its descendants. Also removes pm_runtime_suspended_if_enabled() because it's now unused. Signed-off-by: Tomeu Vizoso Signed-off-by: Alan Stern Signed-off-by: Rafael J. Wysocki

Merge branch 'pm-wakeirq'

2015-06-18T23:18:14+00:00

* pm-wakeirq: PM / wakeirq: Fix typo in prototype for dev_pm_set_dedicated_wake_irq PM / Wakeirq: Add automated device wake IRQ handling

PM / sleep: trace_device_pm_callback coverage in dpm_prepare/complete

2015-06-10T00:24:49+00:00

Move the trace_device_pm_callback locations for dpm_prepare and dpm_complete to encompass the attempt to capture the device mutex prior to callback. This is needed by analyze_suspend to identify gaps in the trace output caused by the delay in locking the mutex for a device. Signed-off-by: Todd Brandt Signed-off-by: Rafael J. Wysocki

PM / Wakeirq: Add automated device wake IRQ handling

2015-05-19T23:56:31+00:00

Turns out we can automate the handling for the device_may_wakeup() quite a bit by using the kernel wakeup source list as suggested by Rafael J. Wysocki . And as some hardware has separate dedicated wake-up interrupt in addition to the IO interrupt, we can automate the handling by adding a generic threaded interrupt handler that just calls the device PM runtime to wake up the device. This allows dropping code from device drivers as we currently are doing it in multiple ways, and often wrong. For most drivers, we should be able to drop the following boilerplate code from runtime_suspend and runtime_resume functions: ... device_init_wakeup(dev, true); ... if (device_may_wakeup(dev)) enable_irq_wake(irq); ... if (device_may_wakeup(dev)) disable_irq_wake(irq); ... device_init_wakeup(dev, false); ... We can replace it with just the following init and exit time code: ... device_init_wakeup(dev, true); dev_pm_set_wake_irq(dev, irq); ... dev_pm_clear_wake_irq(dev); device_init_wakeup(dev, false); ... And for hardware with dedicated wake-up interrupts: ... device_init_wakeup(dev, true); dev_pm_set_dedicated_wake_irq(dev, irq); ... dev_pm_clear_wake_irq(dev); device_init_wakeup(dev, false); ... Signed-off-by: Tony Lindgren Signed-off-by: Rafael J. Wysocki

PM / sleep: add pm-trace support for suspending phase

2015-03-18T14:54:27+00:00

Occasionally, the system can't come back up after suspend/resume due to problems of device suspending phase. This patch make PM_TRACE infrastructure cover device suspending phase of suspend/resume process, and the information in RTC can tell developers which device suspending function make system hang. Signed-off-by: Zhonghui Fu Signed-off-by: Rafael J. Wysocki

PM / Sleep: fix async suspend_late/freeze_late error handling

2014-10-27T17:42:26+00:00

If an asynchronous suspend_late or freeze_late callback fails during the SUSPEND, FREEZE or QUIESCE phases, we don't propagate the corresponding error correctly, in effect ignoring the error and continuing the suspend-to-ram/hibernation. During suspend-to-ram this could leave some devices without a valid saved context, leading to a failure to reinitialize them during resume. During hibernation this could leave some devices active interfeering with the creation / restoration of the hibernation image. Also this could leave the corresponding devices without a valid saved context and failure to reinitialize them during resume. Fixes: de377b397272 (PM / sleep: Asynchronous threads for suspend_late) Signed-off-by: Imre Deak Cc: 3.15+ # 3.15+ Signed-off-by: Rafael J. Wysocki

PM / sleep: Export dpm_suspend_late/noirq() and dpm_resume_early/noirq()

2014-09-30T19:05:59+00:00

Subsequent change sets will add platform-related operations between dpm_suspend_late() and dpm_suspend_noirq() as well as between dpm_resume_noirq() and dpm_resume_early() in suspend_enter(), so export these functions for suspend_enter() to be able to call them separately and split the invocations of dpm_suspend_end() and dpm_resume_start() in there accordingly. Signed-off-by: Rafael J. Wysocki