ACPI / PM: Support for LEAVE_SUSPENDED driver flag in ACPI PM domain

Add support for DPM_FLAG_LEAVE_SUSPENDED to the ACPI PM domain by
making it (a) set the power.may_skip_resume status bit for devices
that, from its perspective, may be left in suspend after system
wakeup from sleep and (b) return early from acpi_subsys_resume_noirq()
for devices whose remaining resume callbacks during the transition
under way are going to be skipped by the PM core.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 24 insertions, 3 deletions

diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index e4ffaeec9ec2..5cfe794c36bd 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -990,7 +990,7 @@ void acpi_subsys_complete(struct device *dev)
          * the sleep state it is going out of and it has never been resumed till
          * now, resume it in case the firmware powered it up.
          */
-        if (dev->power.direct_complete && pm_resume_via_firmware())
+        if (pm_runtime_suspended(dev) && pm_resume_via_firmware())
                 pm_request_resume(dev);
 }
 EXPORT_SYMBOL_GPL(acpi_subsys_complete);
@@ -1039,10 +1039,28 @@ EXPORT_SYMBOL_GPL(acpi_subsys_suspend_late);
  */
 int acpi_subsys_suspend_noirq(struct device *dev)
 {
-        if (dev_pm_smart_suspend_and_suspended(dev))
+        int ret;
+
+        if (dev_pm_smart_suspend_and_suspended(dev)) {
+                dev->power.may_skip_resume = true;
                 return 0;
+        }
+
+        ret = pm_generic_suspend_noirq(dev);
+        if (ret)
+                return ret;
+
+        /*
+         * If the target system sleep state is suspend-to-idle, it is sufficient
+         * to check whether or not the device's wakeup settings are good for
+         * runtime PM.  Otherwise, the pm_resume_via_firmware() check will cause
+         * acpi_subsys_complete() to take care of fixing up the device's state
+         * anyway, if need be.
+         */
+        dev->power.may_skip_resume = device_may_wakeup(dev) ||
+                                        !device_can_wakeup(dev);
 
-        return pm_generic_suspend_noirq(dev);
+        return 0;
 }
 EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq);
 
@@ -1052,6 +1070,9 @@ EXPORT_SYMBOL_GPL(acpi_subsys_suspend_noirq);
  */
 int acpi_subsys_resume_noirq(struct device *dev)
 {
+        if (dev_pm_may_skip_resume(dev))
+                return 0;
+
         /*
          * Devices with DPM_FLAG_SMART_SUSPEND may be left in runtime suspend
          * during system suspend, so update their runtime PM status to "active"