Merge bk://linux.bkbits.net/linux-2.5

into kernel.bkbits.net:/home/mochel/linux-2.5-power

drivers/base/power/main.c

@@ -76,6 +76,7 @@ int device_pm_add(struct device * dev)
 
 	pr_debug("PM: Adding info for %s:%s\n",
 		 dev->bus ? dev->bus->name : "No Bus", dev->kobj.name);
+	atomic_set(&dev->power.pm_users,0);
 	down(&dpm_sem);
 	list_add_tail(&dev->power.entry,&dpm_active);
 	device_pm_set_parent(dev,dev->parent);

include/linux/pm.h

@@ -186,9 +186,36 @@ static inline void pm_dev_idle(struct pm_dev *dev) {}
 
 #endif /* CONFIG_PM */
 
+
+/*
+ * Callbacks for platform drivers to implement.
+ */
 extern void (*pm_idle)(void);
 extern void (*pm_power_off)(void);
 
+enum {
+	PM_SUSPEND_ON,
+	PM_SUSPEND_STANDBY,
+	PM_SUSPEND_MEM,
+	PM_SUSPEND_DISK,
+	PM_SUSPEND_MAX,
+};
+
+struct pm_ops {
+	int (*prepare)(u32 state);
+	int (*enter)(u32 state);
+	int (*finish)(u32 state);
+};
+
+extern void pm_set_ops(struct pm_ops *);
+
+extern int pm_suspend(u32 state);
+
+
+/*
+ * Device power management
+ */
+
 struct device;
 
 struct dev_pm_info {

kernel/power/main.c

@@ -8,6 +8,7 @@
  *
  */
 
+#include <linux/suspend.h>
 #include <linux/kobject.h>
 #include <linux/string.h>
 #include <linux/errno.h>
@@ -15,42 +16,194 @@
 #include <linux/pm.h>
 
 
+static DECLARE_MUTEX(pm_sem);
 
-static int standby(void)
+static struct pm_ops * pm_ops = NULL;
+
+/**
+ *	pm_set_ops - Set the global power method table. 
+ *	@ops:	Pointer to ops structure.
+ */
+
+void pm_set_ops(struct pm_ops * ops)
 {
-	return 0;
+	down(&pm_sem);
+	pm_ops = ops;
+	up(&pm_sem);
 }
 
-static int suspend(void)
+
+/**
+ *	pm_suspend_standby - Enter 'standby' state.
+ *	
+ *	'standby' is also known as 'Power-On Suspend'. Here, we power down
+ *	devices, disable interrupts, and enter the state.
+ */
+
+static int pm_suspend_standby(void)
 {
-	return 0;
+	int error = 0;
+	unsigned long flags;
+
+	if (!pm_ops || !pm_ops->enter)
+		return -EPERM;
+
+	if ((error = device_pm_power_down(PM_SUSPEND_STANDBY)))
+		goto Done;
+	local_irq_save(flags);
+	error = pm_ops->enter(PM_SUSPEND_STANDBY);
+	local_irq_restore(flags);
+	device_pm_power_up();
+ Done:
+	return error;
+}
+
+
+/**
+ *	pm_suspend_mem - Enter suspend-to-RAM state.
+ *
+ *	Identical to pm_suspend_standby() - we power down devices, disable 
+ *	interrupts, and enter the low-power state.
+ */
+
+static int pm_suspend_mem(void)
+{
+	int error = 0;
+	unsigned long flags;
+
+	if (!pm_ops || !pm_ops->enter)
+		return -EPERM;
+
+	if ((error = device_pm_power_down(PM_SUSPEND_STANDBY)))
+		goto Done;
+	local_irq_save(flags);
+	error = pm_ops->enter(PM_SUSPEND_STANDBY);
+	local_irq_restore(flags);
+	device_pm_power_up();
+ Done:
+	return error;
 }
 
-static int hibernate(void)
+static int pm_suspend_disk(void)
 {
 	return 0;
 }
 
 #define decl_state(_name) \
-	{ .name = __stringify(_name), .fn = _name }
+	{ .name = __stringify(_name), .fn = pm_suspend_##_name }
 
 struct pm_state {
 	char * name;
 	int (*fn)(void);
 } pm_states[] = {
-	decl_state(standby),
-	decl_state(suspend),
-	decl_state(hibernate),
+	[PM_SUSPEND_STANDBY]	= decl_state(standby),
+	[PM_SUSPEND_MEM]	= decl_state(mem),
+	[PM_SUSPEND_DISK]	= decl_state(disk),
 	{ NULL },
 };
 
 
-static int enter_state(struct pm_state * state)
+/**
+ *	suspend_prepare - Do prep work before entering low-power state.
+ *	@state:		State we're entering.
+ *
+ *	This is common code that is called for each state that we're 
+ *	entering. Allocate a console, stop all processes, then make sure
+ *	the platform can enter the requested state.
+ */
+
+static int suspend_prepare(u32 state)
+{
+	int error = 0;
+
+	pm_prepare_console();
+
+	if (freeze_processes()) {
+		error = -EAGAIN;
+		goto Thaw;
+	}
+
+	if (pm_ops && pm_ops->prepare) {
+		if ((error = pm_ops->prepare(state)))
+			goto Thaw;
+	}
+ Done:
+	pm_restore_console();
+	return error;
+ Thaw:
+	thaw_processes();
+	goto Done;
+}
+
+
+/**
+ *	suspend_finish - Do final work before exiting suspend sequence.
+ *	@state:		State we're coming out of.
+ *
+ *	Call platform code to clean up, restart processes, and free the 
+ *	console that we've allocated.
+ */
+
+static void suspend_finish(u32 state)
+{
+	if (pm_ops && pm_ops->finish)
+		pm_ops->finish(state);
+	thaw_processes();
+	pm_restore_console();
+}
+
+
+/**
+ *	enter_state - Do common work of entering low-power state.
+ *	@state:		pm_state structure for state we're entering.
+ *
+ *	Make sure we're the only ones trying to enter a sleep state. Fail
+ *	if someone has beat us to it, since we don't want anything weird to
+ *	happen when we wake up.
+ *	Then, do the setup for suspend, enter the state, and cleaup (after
+ *	we've woken up).
+ */
+
+static int enter_state(u32 state)
 {
-	return state->fn();
+	int error;
+	struct pm_state * s = &pm_states[state];
+
+	if (down_trylock(&pm_sem))
+		return -EBUSY;
+
+	if ((error = suspend_prepare(state)))
+		goto Unlock;
+
+	if ((error = device_pm_suspend(state)))
+		goto Finish;
+
+	error = s->fn();
+
+	device_pm_resume();
+ Finish:
+	suspend_finish(state);
+ Unlock:
+	up(&pm_sem);
+	return error;
 }
 
 
+/**
+ *	pm_suspend - Externally visible function for suspending system.
+ *	@state:		Enumarted value of state to enter.
+ *
+ *	Determine whether or not value is within range, get state 
+ *	structure, and enter (above).
+ */
+
+int pm_suspend(u32 state)
+{
+	if (state > PM_SUSPEND_ON && state < PM_SUSPEND_MAX)
+		return enter_state(state);
+	return -EINVAL;
+}
+
 
 decl_subsys(power,NULL,NULL);
 
@@ -69,8 +222,8 @@ static struct subsys_attribute _name##_attr = {	\
  *	state - control system power state.
  *
  *	show() returns what states are supported, which is hard-coded to
- *	'standby' (Power-On Suspend), 'suspend' (Suspend-to-RAM), and
- *	'hibernate' (Suspend-to-Disk).
+ *	'standby' (Power-On Suspend), 'mem' (Suspend-to-RAM), and
+ *	'disk' (Suspend-to-Disk).
  *
  *	store() accepts one of those strings, translates it into the 
  *	proper enumerated value, and initiates a suspend transition.
@@ -87,22 +240,25 @@ static ssize_t state_show(struct subsystem * subsys, char * buf)
 	return (s - buf);
 }
 
-static ssize_t state_store(struct subsystem * s, const char * buf, size_t n)
+static ssize_t state_store(struct subsystem * subsys, const char * buf, size_t n)
 {
-	struct pm_state * state;
+	u32 state;
+	struct pm_state * s;
 	int error;
 	char * end = strchr(buf,'\n');
 	
 	if (end)
 		*end = '\0';
 
-	for (state = &pm_states[0]; state; state++) {
-		if (!strcmp(buf,state->name))
+	for (state = 0; state < PM_SUSPEND_MAX; state++) {
+		s = &pm_states[state];
+		if (s->name && !strcmp(buf,s->name))
 			break;
 	}
-	if (!state)
-		return -EINVAL;
+	if (s)
 		error = enter_state(state);
+	else
+		error = -EINVAL;
 	return error ? error : n;
 }