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path: root/drivers/base/power/suspend.c
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Diffstat (limited to 'drivers/base/power/suspend.c')
-rw-r--r--drivers/base/power/suspend.c122
1 files changed, 92 insertions, 30 deletions
diff --git a/drivers/base/power/suspend.c b/drivers/base/power/suspend.c
index 69509e02f703c6..10e8032aee1afe 100644
--- a/drivers/base/power/suspend.c
+++ b/drivers/base/power/suspend.c
@@ -65,7 +65,19 @@ int suspend_device(struct device * dev, pm_message_t state)
dev->power.prev_state = dev->power.power_state;
- if (dev->bus && dev->bus->suspend && !dev->power.power_state.event) {
+ if (dev->class && dev->class->suspend && !dev->power.power_state.event) {
+ dev_dbg(dev, "class %s%s\n",
+ suspend_verb(state.event),
+ ((state.event == PM_EVENT_SUSPEND)
+ && device_may_wakeup(dev))
+ ? ", may wakeup"
+ : ""
+ );
+ error = dev->class->suspend(dev, state);
+ suspend_report_result(dev->class->suspend, error);
+ }
+
+ if (!error && dev->bus && dev->bus->suspend && !dev->power.power_state.event) {
dev_dbg(dev, "%s%s\n",
suspend_verb(state.event),
((state.event == PM_EVENT_SUSPEND)
@@ -81,15 +93,74 @@ int suspend_device(struct device * dev, pm_message_t state)
}
+/*
+ * This is called with interrupts off, only a single CPU
+ * running. We can't do down() on a semaphore (and we don't
+ * need the protection)
+ */
+static int suspend_device_late(struct device *dev, pm_message_t state)
+{
+ int error = 0;
+
+ if (dev->power.power_state.event) {
+ dev_dbg(dev, "PM: suspend_late %d-->%d\n",
+ dev->power.power_state.event, state.event);
+ }
+
+ if (dev->bus && dev->bus->suspend_late && !dev->power.power_state.event) {
+ dev_dbg(dev, "LATE %s%s\n",
+ suspend_verb(state.event),
+ ((state.event == PM_EVENT_SUSPEND)
+ && device_may_wakeup(dev))
+ ? ", may wakeup"
+ : ""
+ );
+ error = dev->bus->suspend_late(dev, state);
+ suspend_report_result(dev->bus->suspend_late, error);
+ }
+ return error;
+}
+
+/**
+ * device_prepare_suspend - save state and prepare to suspend
+ *
+ * NOTE! Devices cannot detach at this point - not only do we
+ * hold the device list semaphores over the whole prepare, but
+ * the whole point is to do non-invasive preparatory work, not
+ * the actual suspend.
+ */
+int device_prepare_suspend(pm_message_t state)
+{
+ int error = 0;
+ struct device * dev;
+
+ down(&dpm_sem);
+ down(&dpm_list_sem);
+ list_for_each_entry_reverse(dev, &dpm_active, power.entry) {
+ if (!dev->bus || !dev->bus->suspend_prepare)
+ continue;
+ error = dev->bus->suspend_prepare(dev, state);
+ if (error)
+ break;
+ }
+ up(&dpm_list_sem);
+ up(&dpm_sem);
+ return error;
+}
+
/**
* device_suspend - Save state and stop all devices in system.
* @state: Power state to put each device in.
*
* Walk the dpm_active list, call ->suspend() for each device, and move
- * it to dpm_off.
- * Check the return value for each. If it returns 0, then we move the
- * the device to the dpm_off list. If it returns -EAGAIN, we move it to
- * the dpm_off_irq list. If we get a different error, try and back out.
+ * it to the dpm_off list.
+ *
+ * (For historical reasons, if it returns -EAGAIN, that used to mean
+ * that the device would be called again with interrupts disabled.
+ * These days, we use the "suspend_late()" callback for that, so we
+ * print a warning and consider it an error).
+ *
+ * If we get a different error, try and back out.
*
* If we hit a failure with any of the devices, call device_resume()
* above to bring the suspended devices back to life.
@@ -115,39 +186,27 @@ int device_suspend(pm_message_t state)
/* Check if the device got removed */
if (!list_empty(&dev->power.entry)) {
- /* Move it to the dpm_off or dpm_off_irq list */
+ /* Move it to the dpm_off list */
if (!error)
list_move(&dev->power.entry, &dpm_off);
- else if (error == -EAGAIN) {
- list_move(&dev->power.entry, &dpm_off_irq);
- error = 0;
- }
}
if (error)
printk(KERN_ERR "Could not suspend device %s: "
- "error %d\n", kobject_name(&dev->kobj), error);
+ "error %d%s\n",
+ kobject_name(&dev->kobj), error,
+ error == -EAGAIN ? " (please convert to suspend_late)" : "");
put_device(dev);
}
up(&dpm_list_sem);
- if (error) {
- /* we failed... before resuming, bring back devices from
- * dpm_off_irq list back to main dpm_off list, we do want
- * to call resume() on them, in case they partially suspended
- * despite returning -EAGAIN
- */
- while (!list_empty(&dpm_off_irq)) {
- struct list_head * entry = dpm_off_irq.next;
- list_move(entry, &dpm_off);
- }
+ if (error)
dpm_resume();
- }
+
up(&dpm_sem);
return error;
}
EXPORT_SYMBOL_GPL(device_suspend);
-
/**
* device_power_down - Shut down special devices.
* @state: Power state to enter.
@@ -162,14 +221,17 @@ int device_power_down(pm_message_t state)
int error = 0;
struct device * dev;
- list_for_each_entry_reverse(dev, &dpm_off_irq, power.entry) {
- if ((error = suspend_device(dev, state)))
- break;
+ while (!list_empty(&dpm_off)) {
+ struct list_head * entry = dpm_off.prev;
+
+ dev = to_device(entry);
+ error = suspend_device_late(dev, state);
+ if (error)
+ goto Error;
+ list_move(&dev->power.entry, &dpm_off_irq);
}
- if (error)
- goto Error;
- if ((error = sysdev_suspend(state)))
- goto Error;
+
+ error = sysdev_suspend(state);
Done:
return error;
Error: