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-rw-r--r--drivers/base/power/main.c344
1 files changed, 340 insertions, 4 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index eb9f38d..0ab4ab2 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -20,19 +20,24 @@
*/
#include <linux/device.h>
+#include <linux/kallsyms.h>
#include <linux/mutex.h>
+#include <linux/pm.h>
+#include <linux/resume-trace.h>
+#include "../base.h"
#include "power.h"
LIST_HEAD(dpm_active);
-LIST_HEAD(dpm_off);
-LIST_HEAD(dpm_off_irq);
+static LIST_HEAD(dpm_off);
+static LIST_HEAD(dpm_off_irq);
-DEFINE_MUTEX(dpm_mtx);
-DEFINE_MUTEX(dpm_list_mtx);
+static DEFINE_MUTEX(dpm_mtx);
+static DEFINE_MUTEX(dpm_list_mtx);
int (*platform_enable_wakeup)(struct device *dev, int is_on);
+
int device_pm_add(struct device *dev)
{
int error;
@@ -61,3 +66,334 @@ void device_pm_remove(struct device *dev)
}
+/*------------------------- Resume routines -------------------------*/
+
+/**
+ * resume_device - Restore state for one device.
+ * @dev: Device.
+ *
+ */
+
+static int resume_device(struct device * dev)
+{
+ int error = 0;
+
+ TRACE_DEVICE(dev);
+ TRACE_RESUME(0);
+
+ down(&dev->sem);
+
+ if (dev->bus && dev->bus->resume) {
+ dev_dbg(dev,"resuming\n");
+ error = dev->bus->resume(dev);
+ }
+
+ if (!error && dev->type && dev->type->resume) {
+ dev_dbg(dev,"resuming\n");
+ error = dev->type->resume(dev);
+ }
+
+ if (!error && dev->class && dev->class->resume) {
+ dev_dbg(dev,"class resume\n");
+ error = dev->class->resume(dev);
+ }
+
+ up(&dev->sem);
+
+ TRACE_RESUME(error);
+ return error;
+}
+
+
+static int resume_device_early(struct device * dev)
+{
+ int error = 0;
+
+ TRACE_DEVICE(dev);
+ TRACE_RESUME(0);
+ if (dev->bus && dev->bus->resume_early) {
+ dev_dbg(dev,"EARLY resume\n");
+ error = dev->bus->resume_early(dev);
+ }
+ TRACE_RESUME(error);
+ return error;
+}
+
+/*
+ * Resume the devices that have either not gone through
+ * the late suspend, or that did go through it but also
+ * went through the early resume
+ */
+static void dpm_resume(void)
+{
+ mutex_lock(&dpm_list_mtx);
+ while(!list_empty(&dpm_off)) {
+ struct list_head * entry = dpm_off.next;
+ struct device * dev = to_device(entry);
+
+ get_device(dev);
+ list_move_tail(entry, &dpm_active);
+
+ mutex_unlock(&dpm_list_mtx);
+ resume_device(dev);
+ mutex_lock(&dpm_list_mtx);
+ put_device(dev);
+ }
+ mutex_unlock(&dpm_list_mtx);
+}
+
+
+/**
+ * device_resume - Restore state of each device in system.
+ *
+ * Walk the dpm_off list, remove each entry, resume the device,
+ * then add it to the dpm_active list.
+ */
+
+void device_resume(void)
+{
+ might_sleep();
+ mutex_lock(&dpm_mtx);
+ dpm_resume();
+ mutex_unlock(&dpm_mtx);
+}
+
+EXPORT_SYMBOL_GPL(device_resume);
+
+
+/**
+ * dpm_power_up - Power on some devices.
+ *
+ * Walk the dpm_off_irq list and power each device up. This
+ * is used for devices that required they be powered down with
+ * interrupts disabled. As devices are powered on, they are moved
+ * to the dpm_active list.
+ *
+ * Interrupts must be disabled when calling this.
+ */
+
+static void dpm_power_up(void)
+{
+ while(!list_empty(&dpm_off_irq)) {
+ struct list_head * entry = dpm_off_irq.next;
+ struct device * dev = to_device(entry);
+
+ list_move_tail(entry, &dpm_off);
+ resume_device_early(dev);
+ }
+}
+
+
+/**
+ * device_power_up - Turn on all devices that need special attention.
+ *
+ * Power on system devices then devices that required we shut them down
+ * with interrupts disabled.
+ * Called with interrupts disabled.
+ */
+
+void device_power_up(void)
+{
+ sysdev_resume();
+ dpm_power_up();
+}
+
+EXPORT_SYMBOL_GPL(device_power_up);
+
+
+/*------------------------- Suspend routines -------------------------*/
+
+/*
+ * 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.
+ *
+ * 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.
+ *
+ * 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)";
+ }
+}
+
+
+static void
+suspend_device_dbg(struct device *dev, pm_message_t state, char *info)
+{
+ dev_dbg(dev, "%s%s%s\n", info, suspend_verb(state.event),
+ ((state.event == PM_EVENT_SUSPEND) && device_may_wakeup(dev)) ?
+ ", may wakeup" : "");
+}
+
+/**
+ * suspend_device - Save state of one device.
+ * @dev: Device.
+ * @state: Power state device is entering.
+ */
+
+static int suspend_device(struct device * dev, pm_message_t state)
+{
+ int error = 0;
+
+ 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->class && dev->class->suspend) {
+ suspend_device_dbg(dev, state, "class ");
+ error = dev->class->suspend(dev, state);
+ suspend_report_result(dev->class->suspend, error);
+ }
+
+ if (!error && dev->type && dev->type->suspend) {
+ suspend_device_dbg(dev, state, "type ");
+ error = dev->type->suspend(dev, state);
+ suspend_report_result(dev->type->suspend, error);
+ }
+
+ if (!error && dev->bus && dev->bus->suspend) {
+ suspend_device_dbg(dev, state, "");
+ 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 acquire a mutex or 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) {
+ suspend_device_dbg(dev, state, "LATE ");
+ 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.
+ *
+ * Walk the dpm_active list, call ->suspend() for each device, and move
+ * 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.
+ *
+ */
+
+int device_suspend(pm_message_t state)
+{
+ int error = 0;
+
+ might_sleep();
+ mutex_lock(&dpm_mtx);
+ mutex_lock(&dpm_list_mtx);
+ while (!list_empty(&dpm_active) && error == 0) {
+ struct list_head * entry = dpm_active.prev;
+ struct device * dev = to_device(entry);
+
+ get_device(dev);
+ mutex_unlock(&dpm_list_mtx);
+
+ error = suspend_device(dev, state);
+
+ mutex_lock(&dpm_list_mtx);
+
+ /* 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);
+ }
+ mutex_unlock(&dpm_list_mtx);
+ if (error)
+ dpm_resume();
+
+ mutex_unlock(&dpm_mtx);
+ return error;
+}
+
+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.
+ */
+
+int device_power_down(pm_message_t state)
+{
+ int error = 0;
+ struct device * dev;
+
+ 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_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);
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