Commit 20f97caf authored by Rafael J. Wysocki's avatar Rafael J. Wysocki
Browse files

PM / QoS: Drop PM_QOS_FLAG_REMOTE_WAKEUP 



The PM QoS flag PM_QOS_FLAG_REMOTE_WAKEUP is not used consistently
and the vast majority of code simply assumes that remote wakeup
should be enabled for devices in runtime suspend if they can
generate wakeup signals, so drop it.

Signed-off-by: default avatarRafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Reviewed-by: default avatarMika Westerberg <mika.westerberg@linux.intel.com>
parent 8a5776a5

Documentation/ABI/testing/sysfs-devices-power

+0 −16
Original line number Diff line number Diff line
@@ -258,19 +258,3 @@ Description: 


		This attribute has no effect on system-wide suspend/resume and

		hibernation.
 


What:		/sys/devices/.../power/pm_qos_remote_wakeup

Date:		September 2012

Contact:	Rafael J. Wysocki <rjw@rjwysocki.net>

Description:

		The /sys/devices/.../power/pm_qos_remote_wakeup attribute

		is used for manipulating the PM QoS "remote wakeup required"

		flag.  If set, this flag indicates to the kernel that the

		device is a source of user events that have to be signaled from

		its low-power states.



		Not all drivers support this attribute.  If it isn't supported,

		it is not present.



		This attribute has no effect on system-wide suspend/resume and

		hibernation.

Documentation/power/pm_qos_interface.txt

+6 −7
Original line number Diff line number Diff line
@@ -98,8 +98,7 @@ Values are updated in response to changes of the request list. 
The target values of resume latency and active state latency tolerance are

simply the minimum of the request values held in the parameter list elements.

The PM QoS flags aggregate value is a gather (bitwise OR) of all list elements'

values.  Two device PM QoS flags are defined currently: PM_QOS_FLAG_NO_POWER_OFF

and PM_QOS_FLAG_REMOTE_WAKEUP.

values.  One device PM QoS flag is defined currently: PM_QOS_FLAG_NO_POWER_OFF.



Note: The aggregated target values are implemented in such a way that reading

the aggregated value does not require any locking mechanism.
@@ -153,14 +152,14 @@ PM QoS list of resume latency constraints and remove sysfs attribute 
pm_qos_resume_latency_us from the device's power directory.



int dev_pm_qos_expose_flags(device, value)

Add a request to the device's PM QoS list of flags and create sysfs attributes

pm_qos_no_power_off and pm_qos_remote_wakeup under the device's power directory

allowing user space to change these flags' value.

Add a request to the device's PM QoS list of flags and create sysfs attribute

pm_qos_no_power_off under the device's power directory allowing user space to

change the value of the PM_QOS_FLAG_NO_POWER_OFF flag.



void dev_pm_qos_hide_flags(device)

Drop the request added by dev_pm_qos_expose_flags() from the device's PM QoS list

of flags and remove sysfs attributes pm_qos_no_power_off and pm_qos_remote_wakeup

under the device's power directory.

of flags and remove sysfs attribute pm_qos_no_power_off from the device's power

directory.



Notification mechanisms:

The per-device PM QoS framework has a per-device notification tree.

drivers/acpi/device_pm.c

+2 −4
Original line number Diff line number Diff line
@@ -581,8 +581,7 @@ static int acpi_dev_pm_get_state(struct device *dev, struct acpi_device *adev, 
		d_min = ret;

		wakeup = device_may_wakeup(dev) && adev->wakeup.flags.valid

			&& adev->wakeup.sleep_state >= target_state;

	} else if (dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) !=

			PM_QOS_FLAGS_NONE) {

	} else {

		wakeup = adev->wakeup.flags.valid;

	}
@@ -865,8 +864,7 @@ int acpi_dev_runtime_suspend(struct device *dev) 
	if (!adev)

		return 0;



	remote_wakeup = dev_pm_qos_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP) >

				PM_QOS_FLAGS_NONE;

	remote_wakeup = acpi_device_can_wakeup(adev);

	if (remote_wakeup) {

		error = acpi_device_wakeup_enable(adev, ACPI_STATE_S0);

		if (error)

drivers/base/power/domain.c

+1 −3
Original line number Diff line number Diff line
@@ -346,9 +346,7 @@ static int genpd_power_off(struct generic_pm_domain *genpd, bool one_dev_on, 
	list_for_each_entry(pdd, &genpd->dev_list, list_node) {

		enum pm_qos_flags_status stat;



		stat = dev_pm_qos_flags(pdd->dev,

					PM_QOS_FLAG_NO_POWER_OFF

						| PM_QOS_FLAG_REMOTE_WAKEUP);

		stat = dev_pm_qos_flags(pdd->dev, PM_QOS_FLAG_NO_POWER_OFF);

		if (stat > PM_QOS_FLAGS_NONE)

			return -EBUSY;

drivers/base/power/sysfs.c

+0 −28
Original line number Diff line number Diff line
@@ -309,33 +309,6 @@ static ssize_t pm_qos_no_power_off_store(struct device *dev, 
static DEVICE_ATTR(pm_qos_no_power_off, 0644,

		   pm_qos_no_power_off_show, pm_qos_no_power_off_store);



static ssize_t pm_qos_remote_wakeup_show(struct device *dev,

					 struct device_attribute *attr,

					 char *buf)

{

	return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev)

					& PM_QOS_FLAG_REMOTE_WAKEUP));

}



static ssize_t pm_qos_remote_wakeup_store(struct device *dev,

					  struct device_attribute *attr,

					  const char *buf, size_t n)

{

	int ret;



	if (kstrtoint(buf, 0, &ret))

		return -EINVAL;



	if (ret != 0 && ret != 1)

		return -EINVAL;



	ret = dev_pm_qos_update_flags(dev, PM_QOS_FLAG_REMOTE_WAKEUP, ret);

	return ret < 0 ? ret : n;

}



static DEVICE_ATTR(pm_qos_remote_wakeup, 0644,

		   pm_qos_remote_wakeup_show, pm_qos_remote_wakeup_store);



#ifdef CONFIG_PM_SLEEP

static const char _enabled[] = "enabled";

static const char _disabled[] = "disabled";
@@ -671,7 +644,6 @@ static const struct attribute_group pm_qos_latency_tolerance_attr_group = { 


static struct attribute *pm_qos_flags_attrs[] = {

	&dev_attr_pm_qos_no_power_off.attr,

	&dev_attr_pm_qos_remote_wakeup.attr,

	NULL,

};

static const struct attribute_group pm_qos_flags_attr_group = {

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