d288e47c47
The various wakeup flags and their accessor macros in struct
dev_pm_info should be available whenever CONFIG_PM is enabled, not
just when CONFIG_PM_SLEEP is on. Otherwise remote wakeup won't always
be configurable for runtime power management. This patch (as1056b)
fixes the oversight.
David Brownell adds:
More accurately, fixes the "regression" ... as noted sometime
last summer, after 296699de6b
introduced CONFIG_SUSPEND. But that didn't make the regression
list for that kernel, ergo the delay in fixing it.
[rjw: rebased]
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
101 lines
3 KiB
C
101 lines
3 KiB
C
/*
|
|
* drivers/base/power/sysfs.c - sysfs entries for device PM
|
|
*/
|
|
|
|
#include <linux/device.h>
|
|
#include <linux/string.h>
|
|
#include "power.h"
|
|
|
|
int (*platform_enable_wakeup)(struct device *dev, int is_on);
|
|
|
|
|
|
/*
|
|
* wakeup - Report/change current wakeup option for device
|
|
*
|
|
* Some devices support "wakeup" events, which are hardware signals
|
|
* used to activate devices from suspended or low power states. Such
|
|
* devices have one of three values for the sysfs power/wakeup file:
|
|
*
|
|
* + "enabled\n" to issue the events;
|
|
* + "disabled\n" not to do so; or
|
|
* + "\n" for temporary or permanent inability to issue wakeup.
|
|
*
|
|
* (For example, unconfigured USB devices can't issue wakeups.)
|
|
*
|
|
* Familiar examples of devices that can issue wakeup events include
|
|
* keyboards and mice (both PS2 and USB styles), power buttons, modems,
|
|
* "Wake-On-LAN" Ethernet links, GPIO lines, and more. Some events
|
|
* will wake the entire system from a suspend state; others may just
|
|
* wake up the device (if the system as a whole is already active).
|
|
* Some wakeup events use normal IRQ lines; other use special out
|
|
* of band signaling.
|
|
*
|
|
* It is the responsibility of device drivers to enable (or disable)
|
|
* wakeup signaling as part of changing device power states, respecting
|
|
* the policy choices provided through the driver model.
|
|
*
|
|
* Devices may not be able to generate wakeup events from all power
|
|
* states. Also, the events may be ignored in some configurations;
|
|
* for example, they might need help from other devices that aren't
|
|
* active, or which may have wakeup disabled. Some drivers rely on
|
|
* wakeup events internally (unless they are disabled), keeping
|
|
* their hardware in low power modes whenever they're unused. This
|
|
* saves runtime power, without requiring system-wide sleep states.
|
|
*/
|
|
|
|
static const char enabled[] = "enabled";
|
|
static const char disabled[] = "disabled";
|
|
|
|
static ssize_t
|
|
wake_show(struct device * dev, struct device_attribute *attr, char * buf)
|
|
{
|
|
return sprintf(buf, "%s\n", device_can_wakeup(dev)
|
|
? (device_may_wakeup(dev) ? enabled : disabled)
|
|
: "");
|
|
}
|
|
|
|
static ssize_t
|
|
wake_store(struct device * dev, struct device_attribute *attr,
|
|
const char * buf, size_t n)
|
|
{
|
|
char *cp;
|
|
int len = n;
|
|
|
|
if (!device_can_wakeup(dev))
|
|
return -EINVAL;
|
|
|
|
cp = memchr(buf, '\n', n);
|
|
if (cp)
|
|
len = cp - buf;
|
|
if (len == sizeof enabled - 1
|
|
&& strncmp(buf, enabled, sizeof enabled - 1) == 0)
|
|
device_set_wakeup_enable(dev, 1);
|
|
else if (len == sizeof disabled - 1
|
|
&& strncmp(buf, disabled, sizeof disabled - 1) == 0)
|
|
device_set_wakeup_enable(dev, 0);
|
|
else
|
|
return -EINVAL;
|
|
return n;
|
|
}
|
|
|
|
static DEVICE_ATTR(wakeup, 0644, wake_show, wake_store);
|
|
|
|
|
|
static struct attribute * power_attrs[] = {
|
|
&dev_attr_wakeup.attr,
|
|
NULL,
|
|
};
|
|
static struct attribute_group pm_attr_group = {
|
|
.name = "power",
|
|
.attrs = power_attrs,
|
|
};
|
|
|
|
int dpm_sysfs_add(struct device * dev)
|
|
{
|
|
return sysfs_create_group(&dev->kobj, &pm_attr_group);
|
|
}
|
|
|
|
void dpm_sysfs_remove(struct device * dev)
|
|
{
|
|
sysfs_remove_group(&dev->kobj, &pm_attr_group);
|
|
}
|