diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-power | 13 | ||||
| -rw-r--r-- | drivers/base/power/main.c | 7 | ||||
| -rw-r--r-- | drivers/base/power/power.h | 6 | ||||
| -rw-r--r-- | kernel/power/main.c | 31 |
4 files changed, 50 insertions, 7 deletions
diff --git a/Documentation/ABI/testing/sysfs-power b/Documentation/ABI/testing/sysfs-power index dcff4d0623a..d6a801f45b4 100644 --- a/Documentation/ABI/testing/sysfs-power +++ b/Documentation/ABI/testing/sysfs-power @@ -101,3 +101,16 @@ Description: CAUTION: Using it will cause your machine's real-time (CMOS) clock to be set to a random invalid time after a resume. + +What: /sys/power/pm_async +Date: January 2009 +Contact: Rafael J. Wysocki <rjw@sisk.pl> +Description: + The /sys/power/pm_async file controls the switch allowing the + user space to enable or disable asynchronous suspend and resume + of devices. If enabled, this feature will cause some device + drivers' suspend and resume callbacks to be executed in parallel + with each other and with the main suspend thread. It is enabled + if this file contains "1", which is the default. It may be + disabled by writing "0" to this file, in which case all devices + will be suspended and resumed synchronously. diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 3b44c201dda..7e79201b09b 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -201,7 +201,7 @@ static void dpm_wait(struct device *dev, bool async) if (!dev) return; - if (async || dev->power.async_suspend) + if (async || (pm_async_enabled && dev->power.async_suspend)) wait_for_completion(&dev->power.completion); } @@ -563,7 +563,8 @@ static int device_resume(struct device *dev) { INIT_COMPLETION(dev->power.completion); - if (dev->power.async_suspend && !pm_trace_is_enabled()) { + if (pm_async_enabled && dev->power.async_suspend + && !pm_trace_is_enabled()) { get_device(dev); async_schedule(async_resume, dev); return 0; @@ -867,7 +868,7 @@ static int device_suspend(struct device *dev) { INIT_COMPLETION(dev->power.completion); - if (dev->power.async_suspend) { + if (pm_async_enabled && dev->power.async_suspend) { get_device(dev); async_schedule(async_suspend, dev); return 0; diff --git a/drivers/base/power/power.h b/drivers/base/power/power.h index b8fa1aa5225..c0bd03c83b9 100644 --- a/drivers/base/power/power.h +++ b/drivers/base/power/power.h @@ -12,10 +12,10 @@ static inline void pm_runtime_remove(struct device *dev) {} #ifdef CONFIG_PM_SLEEP -/* - * main.c - */ +/* kernel/power/main.c */ +extern int pm_async_enabled; +/* drivers/base/power/main.c */ extern struct list_head dpm_list; /* The active device list */ static inline struct device *to_device(struct list_head *entry) diff --git a/kernel/power/main.c b/kernel/power/main.c index 0998c713905..b58800b21fc 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -44,6 +44,32 @@ int pm_notifier_call_chain(unsigned long val) == NOTIFY_BAD) ? -EINVAL : 0; } +/* If set, devices may be suspended and resumed asynchronously. */ +int pm_async_enabled = 1; + +static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + return sprintf(buf, "%d\n", pm_async_enabled); +} + +static ssize_t pm_async_store(struct kobject *kobj, struct kobj_attribute *attr, + const char *buf, size_t n) +{ + unsigned long val; + + if (strict_strtoul(buf, 10, &val)) + return -EINVAL; + + if (val > 1) + return -EINVAL; + + pm_async_enabled = val; + return n; +} + +power_attr(pm_async); + #ifdef CONFIG_PM_DEBUG int pm_test_level = TEST_NONE; @@ -208,9 +234,12 @@ static struct attribute * g[] = { #ifdef CONFIG_PM_TRACE &pm_trace_attr.attr, #endif -#if defined(CONFIG_PM_SLEEP) && defined(CONFIG_PM_DEBUG) +#ifdef CONFIG_PM_SLEEP + &pm_async_attr.attr, +#ifdef CONFIG_PM_DEBUG &pm_test_attr.attr, #endif +#endif NULL, }; |