diff options
Diffstat (limited to 'drivers/base/power/sysfs.c')
| -rw-r--r-- | drivers/base/power/sysfs.c | 735 |
1 files changed, 735 insertions, 0 deletions
diff --git a/drivers/base/power/sysfs.c b/drivers/base/power/sysfs.c new file mode 100644 index 000000000..d713738ce --- /dev/null +++ b/drivers/base/power/sysfs.c @@ -0,0 +1,735 @@ +/* + * drivers/base/power/sysfs.c - sysfs entries for device PM + */ + +#include <linux/device.h> +#include <linux/string.h> +#include <linux/export.h> +#include <linux/pm_qos.h> +#include <linux/pm_runtime.h> +#include <linux/atomic.h> +#include <linux/jiffies.h> +#include "power.h" + +/* + * control - Report/change current runtime PM setting of the device + * + * Runtime power management of a device can be blocked with the help of + * this attribute. All devices have one of the following two values for + * the power/control file: + * + * + "auto\n" to allow the device to be power managed at run time; + * + "on\n" to prevent the device from being power managed at run time; + * + * The default for all devices is "auto", which means that devices may be + * subject to automatic power management, depending on their drivers. + * Changing this attribute to "on" prevents the driver from power managing + * the device at run time. Doing that while the device is suspended causes + * it to be woken up. + * + * 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. + * + * async - Report/change current async suspend setting for the device + * + * Asynchronous suspend and resume of the device during system-wide power + * state transitions can be enabled by writing "enabled" to this file. + * Analogously, if "disabled" is written to this file, the device will be + * suspended and resumed synchronously. + * + * All devices have one of the following two values for power/async: + * + * + "enabled\n" to permit the asynchronous suspend/resume of the device; + * + "disabled\n" to forbid it; + * + * NOTE: It generally is unsafe to permit the asynchronous suspend/resume + * of a device unless it is certain that all of the PM dependencies of the + * device are known to the PM core. However, for some devices this + * attribute is set to "enabled" by bus type code or device drivers and in + * that cases it should be safe to leave the default value. + * + * autosuspend_delay_ms - Report/change a device's autosuspend_delay value + * + * Some drivers don't want to carry out a runtime suspend as soon as a + * device becomes idle; they want it always to remain idle for some period + * of time before suspending it. This period is the autosuspend_delay + * value (expressed in milliseconds) and it can be controlled by the user. + * If the value is negative then the device will never be runtime + * suspended. + * + * NOTE: The autosuspend_delay_ms attribute and the autosuspend_delay + * value are used only if the driver calls pm_runtime_use_autosuspend(). + * + * wakeup_count - Report the number of wakeup events related to the device + */ + +const char power_group_name[] = "power"; +EXPORT_SYMBOL_GPL(power_group_name); + +static const char ctrl_auto[] = "auto"; +static const char ctrl_on[] = "on"; + +static ssize_t control_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%s\n", + dev->power.runtime_auto ? ctrl_auto : ctrl_on); +} + +static ssize_t control_store(struct device * dev, struct device_attribute *attr, + const char * buf, size_t n) +{ + device_lock(dev); + if (sysfs_streq(buf, ctrl_auto)) + pm_runtime_allow(dev); + else if (sysfs_streq(buf, ctrl_on)) + pm_runtime_forbid(dev); + else + n = -EINVAL; + device_unlock(dev); + return n; +} + +static DEVICE_ATTR_RW(control); + +static ssize_t runtime_active_time_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int ret; + spin_lock_irq(&dev->power.lock); + update_pm_runtime_accounting(dev); + ret = sprintf(buf, "%i\n", jiffies_to_msecs(dev->power.active_jiffies)); + spin_unlock_irq(&dev->power.lock); + return ret; +} + +static DEVICE_ATTR_RO(runtime_active_time); + +static ssize_t runtime_suspended_time_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + int ret; + spin_lock_irq(&dev->power.lock); + update_pm_runtime_accounting(dev); + ret = sprintf(buf, "%i\n", + jiffies_to_msecs(dev->power.suspended_jiffies)); + spin_unlock_irq(&dev->power.lock); + return ret; +} + +static DEVICE_ATTR_RO(runtime_suspended_time); + +static ssize_t runtime_status_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + const char *p; + + if (dev->power.runtime_error) { + p = "error\n"; + } else if (dev->power.disable_depth) { + p = "unsupported\n"; + } else { + switch (dev->power.runtime_status) { + case RPM_SUSPENDED: + p = "suspended\n"; + break; + case RPM_SUSPENDING: + p = "suspending\n"; + break; + case RPM_RESUMING: + p = "resuming\n"; + break; + case RPM_ACTIVE: + p = "active\n"; + break; + default: + return -EIO; + } + } + return sprintf(buf, p); +} + +static DEVICE_ATTR_RO(runtime_status); + +static ssize_t autosuspend_delay_ms_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + if (!dev->power.use_autosuspend) + return -EIO; + return sprintf(buf, "%d\n", dev->power.autosuspend_delay); +} + +static ssize_t autosuspend_delay_ms_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t n) +{ + long delay; + + if (!dev->power.use_autosuspend) + return -EIO; + + if (kstrtol(buf, 10, &delay) != 0 || delay != (int) delay) + return -EINVAL; + + device_lock(dev); + pm_runtime_set_autosuspend_delay(dev, delay); + device_unlock(dev); + return n; +} + +static DEVICE_ATTR_RW(autosuspend_delay_ms); + +static ssize_t pm_qos_resume_latency_us_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + s32 value = dev_pm_qos_requested_resume_latency(dev); + + if (value == 0) + return sprintf(buf, "n/a\n"); + if (value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT) + value = 0; + + return sprintf(buf, "%d\n", value); +} + +static ssize_t pm_qos_resume_latency_us_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t n) +{ + s32 value; + int ret; + + if (!kstrtos32(buf, 0, &value)) { + /* + * Prevent users from writing negative or "no constraint" values + * directly. + */ + if (value < 0 || value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT) + return -EINVAL; + + if (value == 0) + value = PM_QOS_RESUME_LATENCY_NO_CONSTRAINT; + } else if (sysfs_streq(buf, "n/a")) { + value = 0; + } else { + return -EINVAL; + } + + ret = dev_pm_qos_update_request(dev->power.qos->resume_latency_req, + value); + return ret < 0 ? ret : n; +} + +static DEVICE_ATTR_RW(pm_qos_resume_latency_us); + +static ssize_t pm_qos_latency_tolerance_us_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + s32 value = dev_pm_qos_get_user_latency_tolerance(dev); + + if (value < 0) + return sprintf(buf, "auto\n"); + if (value == PM_QOS_LATENCY_ANY) + return sprintf(buf, "any\n"); + + return sprintf(buf, "%d\n", value); +} + +static ssize_t pm_qos_latency_tolerance_us_store(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t n) +{ + s32 value; + int ret; + + if (kstrtos32(buf, 0, &value) == 0) { + /* Users can't write negative values directly */ + if (value < 0) + return -EINVAL; + } else { + if (sysfs_streq(buf, "auto")) + value = PM_QOS_LATENCY_TOLERANCE_NO_CONSTRAINT; + else if (sysfs_streq(buf, "any")) + value = PM_QOS_LATENCY_ANY; + else + return -EINVAL; + } + ret = dev_pm_qos_update_user_latency_tolerance(dev, value); + return ret < 0 ? ret : n; +} + +static DEVICE_ATTR_RW(pm_qos_latency_tolerance_us); + +static ssize_t pm_qos_no_power_off_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev) + & PM_QOS_FLAG_NO_POWER_OFF)); +} + +static ssize_t pm_qos_no_power_off_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_NO_POWER_OFF, ret); + return ret < 0 ? ret : n; +} + +static DEVICE_ATTR_RW(pm_qos_no_power_off); + +#ifdef CONFIG_PM_SLEEP +static const char _enabled[] = "enabled"; +static const char _disabled[] = "disabled"; + +static ssize_t wakeup_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 wakeup_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t n) +{ + if (!device_can_wakeup(dev)) + return -EINVAL; + + if (sysfs_streq(buf, _enabled)) + device_set_wakeup_enable(dev, 1); + else if (sysfs_streq(buf, _disabled)) + device_set_wakeup_enable(dev, 0); + else + return -EINVAL; + return n; +} + +static DEVICE_ATTR_RW(wakeup); + +static ssize_t wakeup_count_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + unsigned long count = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + count = dev->power.wakeup->wakeup_count; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR_RO(wakeup_count); + +static ssize_t wakeup_active_count_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + unsigned long count = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + count = dev->power.wakeup->active_count; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR_RO(wakeup_active_count); + +static ssize_t wakeup_abort_count_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + unsigned long count = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + count = dev->power.wakeup->wakeup_count; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR_RO(wakeup_abort_count); + +static ssize_t wakeup_expire_count_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + unsigned long count = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + count = dev->power.wakeup->expire_count; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lu\n", count) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR_RO(wakeup_expire_count); + +static ssize_t wakeup_active_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + unsigned int active = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + active = dev->power.wakeup->active; + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%u\n", active) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR_RO(wakeup_active); + +static ssize_t wakeup_total_time_ms_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + s64 msec = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + msec = ktime_to_ms(dev->power.wakeup->total_time); + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR_RO(wakeup_total_time_ms); + +static ssize_t wakeup_max_time_ms_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + s64 msec = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + msec = ktime_to_ms(dev->power.wakeup->max_time); + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR_RO(wakeup_max_time_ms); + +static ssize_t wakeup_last_time_ms_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + s64 msec = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + msec = ktime_to_ms(dev->power.wakeup->last_time); + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR_RO(wakeup_last_time_ms); + +#ifdef CONFIG_PM_AUTOSLEEP +static ssize_t wakeup_prevent_sleep_time_ms_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + s64 msec = 0; + bool enabled = false; + + spin_lock_irq(&dev->power.lock); + if (dev->power.wakeup) { + msec = ktime_to_ms(dev->power.wakeup->prevent_sleep_time); + enabled = true; + } + spin_unlock_irq(&dev->power.lock); + return enabled ? sprintf(buf, "%lld\n", msec) : sprintf(buf, "\n"); +} + +static DEVICE_ATTR_RO(wakeup_prevent_sleep_time_ms); +#endif /* CONFIG_PM_AUTOSLEEP */ +#endif /* CONFIG_PM_SLEEP */ + +#ifdef CONFIG_PM_ADVANCED_DEBUG +static ssize_t runtime_usage_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count)); +} +static DEVICE_ATTR_RO(runtime_usage); + +static ssize_t runtime_active_kids_show(struct device *dev, + struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", dev->power.ignore_children ? + 0 : atomic_read(&dev->power.child_count)); +} +static DEVICE_ATTR_RO(runtime_active_kids); + +static ssize_t runtime_enabled_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + if (dev->power.disable_depth && (dev->power.runtime_auto == false)) + return sprintf(buf, "disabled & forbidden\n"); + if (dev->power.disable_depth) + return sprintf(buf, "disabled\n"); + if (dev->power.runtime_auto == false) + return sprintf(buf, "forbidden\n"); + return sprintf(buf, "enabled\n"); +} +static DEVICE_ATTR_RO(runtime_enabled); + +#ifdef CONFIG_PM_SLEEP +static ssize_t async_show(struct device *dev, struct device_attribute *attr, + char *buf) +{ + return sprintf(buf, "%s\n", + device_async_suspend_enabled(dev) ? + _enabled : _disabled); +} + +static ssize_t async_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t n) +{ + if (sysfs_streq(buf, _enabled)) + device_enable_async_suspend(dev); + else if (sysfs_streq(buf, _disabled)) + device_disable_async_suspend(dev); + else + return -EINVAL; + return n; +} + +static DEVICE_ATTR_RW(async); + +#endif /* CONFIG_PM_SLEEP */ +#endif /* CONFIG_PM_ADVANCED_DEBUG */ + +static struct attribute *power_attrs[] = { +#ifdef CONFIG_PM_ADVANCED_DEBUG +#ifdef CONFIG_PM_SLEEP + &dev_attr_async.attr, +#endif + &dev_attr_runtime_status.attr, + &dev_attr_runtime_usage.attr, + &dev_attr_runtime_active_kids.attr, + &dev_attr_runtime_enabled.attr, +#endif /* CONFIG_PM_ADVANCED_DEBUG */ + NULL, +}; +static const struct attribute_group pm_attr_group = { + .name = power_group_name, + .attrs = power_attrs, +}; + +static struct attribute *wakeup_attrs[] = { +#ifdef CONFIG_PM_SLEEP + &dev_attr_wakeup.attr, + &dev_attr_wakeup_count.attr, + &dev_attr_wakeup_active_count.attr, + &dev_attr_wakeup_abort_count.attr, + &dev_attr_wakeup_expire_count.attr, + &dev_attr_wakeup_active.attr, + &dev_attr_wakeup_total_time_ms.attr, + &dev_attr_wakeup_max_time_ms.attr, + &dev_attr_wakeup_last_time_ms.attr, +#ifdef CONFIG_PM_AUTOSLEEP + &dev_attr_wakeup_prevent_sleep_time_ms.attr, +#endif +#endif + NULL, +}; +static const struct attribute_group pm_wakeup_attr_group = { + .name = power_group_name, + .attrs = wakeup_attrs, +}; + +static struct attribute *runtime_attrs[] = { +#ifndef CONFIG_PM_ADVANCED_DEBUG + &dev_attr_runtime_status.attr, +#endif + &dev_attr_control.attr, + &dev_attr_runtime_suspended_time.attr, + &dev_attr_runtime_active_time.attr, + &dev_attr_autosuspend_delay_ms.attr, + NULL, +}; +static const struct attribute_group pm_runtime_attr_group = { + .name = power_group_name, + .attrs = runtime_attrs, +}; + +static struct attribute *pm_qos_resume_latency_attrs[] = { + &dev_attr_pm_qos_resume_latency_us.attr, + NULL, +}; +static const struct attribute_group pm_qos_resume_latency_attr_group = { + .name = power_group_name, + .attrs = pm_qos_resume_latency_attrs, +}; + +static struct attribute *pm_qos_latency_tolerance_attrs[] = { + &dev_attr_pm_qos_latency_tolerance_us.attr, + NULL, +}; +static const struct attribute_group pm_qos_latency_tolerance_attr_group = { + .name = power_group_name, + .attrs = pm_qos_latency_tolerance_attrs, +}; + +static struct attribute *pm_qos_flags_attrs[] = { + &dev_attr_pm_qos_no_power_off.attr, + NULL, +}; +static const struct attribute_group pm_qos_flags_attr_group = { + .name = power_group_name, + .attrs = pm_qos_flags_attrs, +}; + +int dpm_sysfs_add(struct device *dev) +{ + int rc; + + rc = sysfs_create_group(&dev->kobj, &pm_attr_group); + if (rc) + return rc; + + if (pm_runtime_callbacks_present(dev)) { + rc = sysfs_merge_group(&dev->kobj, &pm_runtime_attr_group); + if (rc) + goto err_out; + } + if (device_can_wakeup(dev)) { + rc = sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group); + if (rc) + goto err_runtime; + } + if (dev->power.set_latency_tolerance) { + rc = sysfs_merge_group(&dev->kobj, + &pm_qos_latency_tolerance_attr_group); + if (rc) + goto err_wakeup; + } + return 0; + + err_wakeup: + sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group); + err_runtime: + sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group); + err_out: + sysfs_remove_group(&dev->kobj, &pm_attr_group); + return rc; +} + +int wakeup_sysfs_add(struct device *dev) +{ + return sysfs_merge_group(&dev->kobj, &pm_wakeup_attr_group); +} + +void wakeup_sysfs_remove(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group); +} + +int pm_qos_sysfs_add_resume_latency(struct device *dev) +{ + return sysfs_merge_group(&dev->kobj, &pm_qos_resume_latency_attr_group); +} + +void pm_qos_sysfs_remove_resume_latency(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_qos_resume_latency_attr_group); +} + +int pm_qos_sysfs_add_flags(struct device *dev) +{ + return sysfs_merge_group(&dev->kobj, &pm_qos_flags_attr_group); +} + +void pm_qos_sysfs_remove_flags(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_qos_flags_attr_group); +} + +int pm_qos_sysfs_add_latency_tolerance(struct device *dev) +{ + return sysfs_merge_group(&dev->kobj, + &pm_qos_latency_tolerance_attr_group); +} + +void pm_qos_sysfs_remove_latency_tolerance(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group); +} + +void rpm_sysfs_remove(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_runtime_attr_group); +} + +void dpm_sysfs_remove(struct device *dev) +{ + sysfs_unmerge_group(&dev->kobj, &pm_qos_latency_tolerance_attr_group); + dev_pm_qos_constraints_destroy(dev); + rpm_sysfs_remove(dev); + sysfs_unmerge_group(&dev->kobj, &pm_wakeup_attr_group); + sysfs_remove_group(&dev->kobj, &pm_attr_group); +} |