===================================================================
@@ -26,6 +26,7 @@
#include <linux/spinlock.h>
#include <linux/wait.h>
#include <linux/timer.h>
+#include <linux/completion.h>
/*
* Callbacks for platform drivers to implement.
@@ -412,9 +413,11 @@ struct dev_pm_info {
pm_message_t power_state;
unsigned int can_wakeup:1;
unsigned int should_wakeup:1;
+ unsigned async_suspend:1;
enum dpm_state status; /* Owned by the PM core */
#ifdef CONFIG_PM_SLEEP
struct list_head entry;
+ struct completion completion;
#endif
#ifdef CONFIG_PM_RUNTIME
struct timer_list suspend_timer;
===================================================================
@@ -25,6 +25,7 @@
#include <linux/resume-trace.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
+#include <linux/async.h>
#include "../base.h"
#include "power.h"
@@ -42,6 +43,7 @@
LIST_HEAD(dpm_list);
static DEFINE_MUTEX(dpm_list_mtx);
+static pm_message_t pm_transition;
/*
* Set once the preparation of devices for a PM transition has started, reset
@@ -56,6 +58,7 @@ static bool transition_started;
void device_pm_init(struct device *dev)
{
dev->power.status = DPM_ON;
+ init_completion(&dev->power.completion);
pm_runtime_init(dev);
}
@@ -111,6 +114,7 @@ void device_pm_remove(struct device *dev
pr_debug("PM: Removing info for %s:%s\n",
dev->bus ? dev->bus->name : "No Bus",
kobject_name(&dev->kobj));
+ complete_all(&dev->power.completion);
mutex_lock(&dpm_list_mtx);
list_del_init(&dev->power.entry);
mutex_unlock(&dpm_list_mtx);
@@ -188,6 +192,31 @@ static void initcall_debug_report(struct
}
/**
+ * dpm_wait - Wait for a PM operation to complete.
+ * @dev: Device to wait for.
+ * @async: If unset, wait only if the device's power.async_suspend flag is set.
+ */
+static void dpm_wait(struct device *dev, bool async)
+{
+ if (!dev)
+ return;
+
+ if (async || dev->power.async_suspend)
+ wait_for_completion(&dev->power.completion);
+}
+
+static int dpm_wait_fn(struct device *dev, void *async_ptr)
+{
+ dpm_wait(dev, *((bool *)async_ptr));
+ return 0;
+}
+
+static void dpm_wait_for_children(struct device *dev, bool async)
+{
+ device_for_each_child(dev, &async, dpm_wait_fn);
+}
+
+/**
* pm_op - Execute the PM operation appropriate for given PM event.
* @dev: Device to handle.
* @ops: PM operations to choose from.
@@ -466,17 +495,19 @@ static int legacy_resume(struct device *
}
/**
- * device_resume - Execute "resume" callbacks for given device.
+ * __device_resume - Execute "resume" callbacks for given device.
* @dev: Device to handle.
* @state: PM transition of the system being carried out.
+ * @async: If true, the device is being resumed asynchronously.
*/
-static int device_resume(struct device *dev, pm_message_t state)
+static int __device_resume(struct device *dev, pm_message_t state, bool async)
{
int error = 0;
TRACE_DEVICE(dev);
TRACE_RESUME(0);
+ dpm_wait(dev->parent, async);
down(&dev->sem);
if (dev->bus) {
@@ -511,11 +542,36 @@ static int device_resume(struct device *
}
End:
up(&dev->sem);
+ complete_all(&dev->power.completion);
TRACE_RESUME(error);
return error;
}
+static void async_resume(void *data, async_cookie_t cookie)
+{
+ struct device *dev = (struct device *)data;
+ int error;
+
+ error = __device_resume(dev, pm_transition, true);
+ if (error)
+ pm_dev_err(dev, pm_transition, " async", error);
+ put_device(dev);
+}
+
+static int device_resume(struct device *dev)
+{
+ INIT_COMPLETION(dev->power.completion);
+
+ if (dev->power.async_suspend && !pm_trace_is_enabled()) {
+ get_device(dev);
+ async_schedule(async_resume, dev);
+ return 0;
+ }
+
+ return __device_resume(dev, pm_transition, false);
+}
+
/**
* dpm_resume - Execute "resume" callbacks for non-sysdev devices.
* @state: PM transition of the system being carried out.
@@ -530,6 +586,7 @@ static void dpm_resume(pm_message_t stat
INIT_LIST_HEAD(&list);
mutex_lock(&dpm_list_mtx);
+ pm_transition = state;
while (!list_empty(&dpm_list)) {
struct device *dev = to_device(dpm_list.next);
@@ -540,7 +597,7 @@ static void dpm_resume(pm_message_t stat
dev->power.status = DPM_RESUMING;
mutex_unlock(&dpm_list_mtx);
- error = device_resume(dev, state);
+ error = device_resume(dev);
mutex_lock(&dpm_list_mtx);
if (error)
@@ -555,6 +612,7 @@ static void dpm_resume(pm_message_t stat
}
list_splice(&list, &dpm_list);
mutex_unlock(&dpm_list_mtx);
+ async_synchronize_full();
dpm_show_time(starttime, state, NULL);
}
@@ -732,17 +790,24 @@ static int legacy_suspend(struct device
return error;
}
+static int async_error;
+
/**
* device_suspend - Execute "suspend" callbacks for given device.
* @dev: Device to handle.
* @state: PM transition of the system being carried out.
+ * @async: If true, the device is being suspended asynchronously.
*/
-static int device_suspend(struct device *dev, pm_message_t state)
+static int __device_suspend(struct device *dev, pm_message_t state, bool async)
{
int error = 0;
+ dpm_wait_for_children(dev, async);
down(&dev->sem);
+ if (async_error)
+ goto End;
+
if (dev->class) {
if (dev->class->pm) {
pm_dev_dbg(dev, state, "class ");
@@ -773,12 +838,44 @@ static int device_suspend(struct device
error = legacy_suspend(dev, state, dev->bus->suspend);
}
}
+
+ if (!error)
+ dev->power.status = DPM_OFF;
+
End:
up(&dev->sem);
+ complete_all(&dev->power.completion);
return error;
}
+static void async_suspend(void *data, async_cookie_t cookie)
+{
+ struct device *dev = (struct device *)data;
+ int error;
+
+ error = __device_suspend(dev, pm_transition, true);
+ if (error) {
+ pm_dev_err(dev, pm_transition, " async", error);
+ async_error = error;
+ }
+
+ put_device(dev);
+}
+
+static int device_suspend(struct device *dev)
+{
+ INIT_COMPLETION(dev->power.completion);
+
+ if (dev->power.async_suspend) {
+ get_device(dev);
+ async_schedule(async_suspend, dev);
+ return 0;
+ }
+
+ return __device_suspend(dev, pm_transition, false);
+}
+
/**
* dpm_suspend - Execute "suspend" callbacks for all non-sysdev devices.
* @state: PM transition of the system being carried out.
@@ -791,13 +888,15 @@ static int dpm_suspend(pm_message_t stat
INIT_LIST_HEAD(&list);
mutex_lock(&dpm_list_mtx);
+ pm_transition = state;
+ async_error = 0;
while (!list_empty(&dpm_list)) {
struct device *dev = to_device(dpm_list.prev);
get_device(dev);
mutex_unlock(&dpm_list_mtx);
- error = device_suspend(dev, state);
+ error = device_suspend(dev);
mutex_lock(&dpm_list_mtx);
if (error) {
@@ -805,13 +904,17 @@ static int dpm_suspend(pm_message_t stat
put_device(dev);
break;
}
- dev->power.status = DPM_OFF;
if (!list_empty(&dev->power.entry))
list_move(&dev->power.entry, &list);
put_device(dev);
+ if (async_error)
+ break;
}
list_splice(&list, dpm_list.prev);
mutex_unlock(&dpm_list_mtx);
+ async_synchronize_full();
+ if (!error)
+ error = async_error;
if (!error)
dpm_show_time(starttime, state, NULL);
return error;
===================================================================
@@ -6,6 +6,11 @@
extern int pm_trace_enabled;
+static inline int pm_trace_is_enabled(void)
+{
+ return pm_trace_enabled;
+}
+
struct device;
extern void set_trace_device(struct device *);
extern void generate_resume_trace(const void *tracedata, unsigned int user);
@@ -17,6 +22,8 @@ extern void generate_resume_trace(const
#else
+static inline int pm_trace_is_enabled(void) { return 0; }
+
#define TRACE_DEVICE(dev) do { } while (0)
#define TRACE_RESUME(dev) do { } while (0)
===================================================================
@@ -472,6 +472,12 @@ static inline int device_is_registered(s
return dev->kobj.state_in_sysfs;
}
+static inline void device_enable_async_suspend(struct device *dev)
+{
+ if (dev->power.status == DPM_ON)
+ dev->power.async_suspend = true;
+}
+
void driver_init(void);
/*