/*
- * suspend.c - Functions for putting devices to sleep.
+ * suspend.c - Functions for putting devices to sleep.
*
* Copyright (c) 2003 Patrick Mochel
* Copyright (c) 2003 Open Source Development Labs
*/
#include <linux/device.h>
+#include <linux/kallsyms.h>
+#include <linux/pm.h>
+#include "../base.h"
#include "power.h"
-
-extern int sysdev_suspend(u32 state);
/*
* The entries in the dpm_active list are in a depth first order, simply
- * because children are guaranteed to be discovered after parents, and
- * are inserted at the back of the list on discovery.
- *
+ * because children are guaranteed to be discovered after parents, and
+ * are inserted at the back of the list on discovery.
+ *
* All list on the suspend path are done in reverse order, so we operate
* on the leaves of the device tree (or forests, depending on how you want
- * to look at it ;) first. As nodes are removed from the back of the list,
- * they are inserted into the front of their destintation lists.
+ * to look at it ;) first. As nodes are removed from the back of the list,
+ * they are inserted into the front of their destintation lists.
*
* Things are the reverse on the resume path - iterations are done in
* forward order, and nodes are inserted at the back of their destination
* lists. This way, the ancestors will be accessed before their descendents.
*/
+static inline char *suspend_verb(u32 event)
+{
+ switch (event) {
+ case PM_EVENT_SUSPEND: return "suspend";
+ case PM_EVENT_FREEZE: return "freeze";
+ case PM_EVENT_PRETHAW: return "prethaw";
+ default: return "(unknown suspend event)";
+ }
+}
+
/**
* suspend_device - Save state of one device.
* @state: Power state device is entering.
*/
-int suspend_device(struct device * dev, u32 state)
+int suspend_device(struct device * dev, pm_message_t state)
{
int error = 0;
- if (dev->bus && dev->bus->suspend)
- error = dev->bus->suspend(dev,state);
+ down(&dev->sem);
+ if (dev->power.power_state.event) {
+ dev_dbg(dev, "PM: suspend %d-->%d\n",
+ dev->power.power_state.event, state.event);
+ }
+ if (dev->power.pm_parent
+ && dev->power.pm_parent->power.power_state.event) {
+ dev_err(dev,
+ "PM: suspend %d->%d, parent %s already %d\n",
+ dev->power.power_state.event, state.event,
+ dev->power.pm_parent->bus_id,
+ dev->power.pm_parent->power.power_state.event);
+ }
- if (!error) {
- list_del(&dev->power.entry);
- list_add(&dev->power.entry,&dpm_off);
- } else if (error == -EAGAIN) {
- list_del(&dev->power.entry);
- list_add(&dev->power.entry,&dpm_off_irq);
+ dev->power.prev_state = dev->power.power_state;
+
+ 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)
+ && device_may_wakeup(dev))
+ ? ", may wakeup"
+ : ""
+ );
+ error = dev->bus->suspend(dev, state);
+ suspend_report_result(dev->bus->suspend, error);
+ }
+ up(&dev->sem);
return error;
}
+/*
+ * 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->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_suspend - Save state and stop all devices in system.
- * @state: Power state to put each device in.
+ * @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.
*
- * If we hit a failure with any of the devices, call device_resume()
- * above to bring the suspended devices back to life.
+ * (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).
*
- * Note this function leaves dpm_sem held to
- * a) block other devices from registering.
- * b) prevent other PM operations from happening after we've begun.
- * c) make sure we're exclusive when we disable interrupts.
+ * 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.
*
*/
-int device_suspend(u32 state)
+int device_suspend(pm_message_t state)
{
int error = 0;
+ might_sleep();
down(&dpm_sem);
- while(!list_empty(&dpm_active)) {
+ down(&dpm_list_sem);
+ while (!list_empty(&dpm_active) && error == 0) {
struct list_head * entry = dpm_active.prev;
struct device * dev = to_device(entry);
- if ((error = suspend_device(dev,state))) {
- if (error != -EAGAIN)
- goto Error;
- else
- error = 0;
+
+ get_device(dev);
+ up(&dpm_list_sem);
+
+ error = suspend_device(dev, state);
+
+ down(&dpm_list_sem);
+
+ /* Check if the device got removed */
+ if (!list_empty(&dev->power.entry)) {
+ /* Move it to the dpm_off list */
+ if (!error)
+ list_move(&dev->power.entry, &dpm_off);
}
+ if (error)
+ printk(KERN_ERR "Could not suspend device %s: "
+ "error %d%s\n",
+ kobject_name(&dev->kobj), error,
+ error == -EAGAIN ? " (please convert to suspend_late)" : "");
+ put_device(dev);
}
- Done:
+ up(&dpm_list_sem);
+ if (error)
+ dpm_resume();
+
up(&dpm_sem);
return error;
- Error:
- dpm_resume();
- goto Done;
}
-EXPORT_SYMBOL(device_suspend);
-
+EXPORT_SYMBOL_GPL(device_suspend);
/**
* device_power_down - Shut down special devices.
* @state: Power state to enter.
*
* Walk the dpm_off_irq list, calling ->power_down() for each device that
- * couldn't power down the device with interrupts enabled. When we're
- * done, power down system devices.
+ * couldn't power down the device with interrupts enabled. When we're
+ * done, power down system devices.
*/
-int device_power_down(u32 state)
+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;
- }
- if (error)
- goto Error;
- if ((error = sysdev_suspend(state)))
- goto Error;
+ 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);
+ }
+
+ error = sysdev_suspend(state);
Done:
return error;
Error:
+ printk(KERN_ERR "Could not power down device %s: "
+ "error %d\n", kobject_name(&dev->kobj), error);
dpm_power_up();
goto Done;
}
-EXPORT_SYMBOL(device_power_down);
+EXPORT_SYMBOL_GPL(device_power_down);
+void __suspend_report_result(const char *function, void *fn, int ret)
+{
+ if (ret) {
+ printk(KERN_ERR "%s(): ", function);
+ print_fn_descriptor_symbol("%s() returns ", (unsigned long)fn);
+ printk("%d\n", ret);
+ }
+}
+EXPORT_SYMBOL_GPL(__suspend_report_result);
git://git.onelab.eu / linux-2.6.git / blobdiff