PM: Check power.needs_force_resume in pm_runtime_force_suspend()
Add a power.needs_force_resume check to pm_runtime_force_suspend() so it need not rely on the runtime PM status of the device when deciding whether or not to return early. With the new check in place, pm_runtime_force_suspend() will also skip devices with the runtime PM status equal to RPM_ACTIVE if they have power.needs_force_resume set, so it won't need to change the RPM status of the device to RPM_SUSPENDED in addition to setting power.needs_force_resume in the case when pm_runtime_need_not_resume() return false. That allows the runtime PM status update to be removed from pm_runtime_force_resume(), so the runtime PM status remains unchanged between the pm_runtime_force_suspend() and pm_runtime_force_resume() calls. This change potentially unbreaks drivers that call pm_runtime_force_suspend() from their ->remove() callbacks because currently, if the device being unbound from its driver has a parent with enabled runtime PM and/or (possibly) device links respecting runtime PM to suppliers, and it is RPM_ACTIVE when the remove takes place, pm_runtime_force_suspend() will not drop the parent's child count and the suppliers' runtime PM usage counters after force-suspending the device unless pm_runtime_need_not_resume() returns 'true' for it. Moreover, because pm_runtime_force_suspend() changes the device's runtime PM status to RPM_SUSPENDED, in the above case pm_runtime_reinit() will not cause those counters to drop, so they will remain nonzero forever effectively preventing the devices in question from runtime-suspending going forward. This change is also needed for pm_runtime_force_suspend() to work with PCI PM and ACPI PM after subsequent changes. Namely, say DPM_FLAG_SMART_SUSPEND is set for a PCI device and its driver uses pm_runtime_force_suspend() as its ->suspend() callback. If pm_runtime_force_suspend() changed the runtime PM status of the device to RPM_SUSPENDED, pci_pm_suspend_noirq() would skip the device due to the dev_pm_skip_suspend() check. Signed-off-by:Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by:
Ulf Hansson <ulf.hansson@linaro.org> Link: https://patch.msgid.link/1855933.VLH7GnMWUR@rjwysocki.net
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