In the case when the no_direct_complete flag is set for the ACPI device, we
can under some conditions during system sleep, avoid runtime resuming the
device in acpi_subsys_suspend|freeze(). This will of course improve the
time it takes for the system to suspend, but also avoid wasting power.
More precisely, from acpi_subsys_suspend|freeze(), let's call
acpi_dev_needs_resume() when the no_direct_complete flag is set, as it
tells us when runtime resume of the device is needed, thus let's avoid it
if possible.
Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
---
drivers/acpi/device_pm.c | 23 +++++++++++++++++++++--
1 file changed, 21 insertions(+), 2 deletions(-)
diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c
index e0324ab..f3061f9 100644
--- a/drivers/acpi/device_pm.c
+++ b/drivers/acpi/device_pm.c
@@ -1056,10 +1056,19 @@ EXPORT_SYMBOL_GPL(acpi_subsys_complete);
* @dev: Device to handle.
*
* Follow PCI and resume devices suspended at run time before running their
- * system suspend callbacks.
+ * system suspend callbacks. However, try to avoid it when no_direct_complete
+ * is set.
*/
int acpi_subsys_suspend(struct device *dev)
{
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+
+ if (!adev)
+ return 0;
+
+ if (adev->no_direct_complete && !acpi_dev_needs_resume(dev, adev))
+ return pm_generic_suspend(dev);
+
pm_runtime_resume(dev);
return pm_generic_suspend(dev);
}
@@ -1117,12 +1126,22 @@ EXPORT_SYMBOL_GPL(acpi_subsys_resume_early);
*/
int acpi_subsys_freeze(struct device *dev)
{
+ struct acpi_device *adev = ACPI_COMPANION(dev);
+
+ if (!adev)
+ return 0;
+
/*
* This used to be done in acpi_subsys_prepare() for all devices and
* some drivers may depend on it, so do it here. Ideally, however,
* runtime-suspended devices should not be touched during freeze/thaw
- * transitions.
+ * transitions. At least when no_direct_complete is set, let's try to
+ * avoid it.
*/
+
+ if (adev->no_direct_complete && !acpi_dev_needs_resume(dev, adev))
+ return pm_generic_freeze(dev);
+
pm_runtime_resume(dev);
return pm_generic_freeze(dev);
}
--
2.7.4
