From: Rafael J. Wysocki <rafael.j.wyso...@intel.com>

Rework the ACPI PM domain's PM callbacks to avoid resuming devices
during system suspend (in order to modify their wakeup settings etc.)
if that isn't necessary.

Signed-off-by: Rafael J. Wysocki <rafael.j.wyso...@intel.com>
---
 drivers/acpi/device_pm.c |   46 ++++++++++++++++++++++++++++++++++++++++++----
 drivers/acpi/scan.c      |    4 ++++
 include/acpi/acpi_bus.h  |    3 ++-
 3 files changed, 48 insertions(+), 5 deletions(-)

Index: linux-pm/drivers/acpi/device_pm.c
===================================================================
--- linux-pm.orig/drivers/acpi/device_pm.c
+++ linux-pm/drivers/acpi/device_pm.c
@@ -907,20 +907,44 @@ int acpi_subsys_prepare(struct device *d
        if (dev->power.ignore_children)
                pm_runtime_resume(dev);
 
+       pm_set_direct_resume(dev, true);
        return pm_generic_prepare(dev);
 }
 EXPORT_SYMBOL_GPL(acpi_subsys_prepare);
 
 /**
- * acpi_subsys_suspend - Run the device driver's suspend callback.
+ * acpi_subsys_suspend - Handle device suspend stage of system suspend.
  * @dev: Device to handle.
- *
- * Follow PCI and resume devices suspended at run time before running their
- * system suspend callbacks.
  */
 int acpi_subsys_suspend(struct device *dev)
 {
+       struct acpi_device *adev = ACPI_COMPANION(dev);
+       u32 sys_target;
+
+       if (!adev || !pm_runtime_enabled_and_suspended(dev)) {
+               pm_set_direct_resume(dev, false);
+               goto out;
+       }
+       if (!pm_direct_resume_is_set(dev)
+           || device_may_wakeup(dev) != !!adev->wakeup.prepare_count)
+               goto resume;
+
+       sys_target = acpi_target_system_state();
+       if (sys_target != ACPI_STATE_S0) {
+               int ret, state;
+
+               if (adev->power.flags.dsw_present)
+                       goto resume;
+
+               ret = acpi_dev_pm_get_state(dev, adev, sys_target, NULL, 
&state);
+               if (!ret && state == adev->power.state)
+                       return 0;
+       }
+
+ resume:
        pm_runtime_resume(dev);
+
+ out:
        return pm_generic_suspend(dev);
 }
 
@@ -954,6 +978,19 @@ int acpi_subsys_resume_early(struct devi
 EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
 
 /**
+ * acpi_subsys_resume - Handle device resume stage of system resume.
+ * @dev: Device to handle.
+ */
+int acpi_subsys_resume(struct device *dev)
+{
+       if (pm_direct_resume_is_set(dev)) {
+               pm_runtime_resume(dev);
+               return 0;
+       }
+       return pm_generic_resume(dev);
+}
+
+/**
  * acpi_subsys_freeze - Run the device driver's freeze callback.
  * @dev: Device to handle.
  */
@@ -982,6 +1019,7 @@ static struct dev_pm_domain acpi_general
                .suspend = acpi_subsys_suspend,
                .suspend_late = acpi_subsys_suspend_late,
                .resume_early = acpi_subsys_resume_early,
+               .resume = acpi_subsys_resume,
                .freeze = acpi_subsys_freeze,
                .poweroff = acpi_subsys_suspend,
                .poweroff_late = acpi_subsys_suspend_late,
Index: linux-pm/include/acpi/acpi_bus.h
===================================================================
--- linux-pm.orig/include/acpi/acpi_bus.h
+++ linux-pm/include/acpi/acpi_bus.h
@@ -261,7 +261,8 @@ struct acpi_device_power_flags {
        u32 inrush_current:1;   /* Serialize Dx->D0 */
        u32 power_removed:1;    /* Optimize Dx->D0 */
        u32 ignore_parent:1;    /* Power is independent of parent power state */
-       u32 reserved:27;
+       u32 dsw_present:1;      /* _DSW present? */
+       u32 reserved:26;
 };
 
 struct acpi_device_power_state {
Index: linux-pm/drivers/acpi/scan.c
===================================================================
--- linux-pm.orig/drivers/acpi/scan.c
+++ linux-pm/drivers/acpi/scan.c
@@ -1551,9 +1551,13 @@ static void acpi_bus_get_power_flags(str
         */
        if (acpi_has_method(device->handle, "_PSC"))
                device->power.flags.explicit_get = 1;
+
        if (acpi_has_method(device->handle, "_IRC"))
                device->power.flags.inrush_current = 1;
 
+       if (acpi_has_method(device->handle, "_DSW"))
+               device->power.flags.dsw_present = 1;
+
        /*
         * Enumerate supported power management states
         */

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to