obj-$(CONFIG_PM) += main.o
obj-$(CONFIG_PM_SLEEP) += console.o
obj-$(CONFIG_FREEZER) += process.o
+obj-$(CONFIG_SUSPEND) += suspend.o
+obj-$(CONFIG_PM_TEST_SUSPEND) += suspend_test.o
obj-$(CONFIG_HIBERNATION) += swsusp.o disk.o snapshot.o swap.o user.o
obj-$(CONFIG_MAGIC_SYSRQ) += poweroff.o
*
*/
-#include <linux/module.h>
-#include <linux/suspend.h>
#include <linux/kobject.h>
#include <linux/string.h>
-#include <linux/delay.h>
-#include <linux/errno.h>
-#include <linux/kmod.h>
-#include <linux/init.h>
-#include <linux/console.h>
-#include <linux/cpu.h>
#include <linux/resume-trace.h>
-#include <linux/freezer.h>
-#include <linux/vmstat.h>
-#include <linux/syscalls.h>
#include "power.h"
#endif /* CONFIG_PM_SLEEP */
-#ifdef CONFIG_SUSPEND
-
-static int suspend_test(int level)
-{
-#ifdef CONFIG_PM_DEBUG
- if (pm_test_level == level) {
- printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n");
- mdelay(5000);
- return 1;
- }
-#endif /* !CONFIG_PM_DEBUG */
- return 0;
-}
-
-#ifdef CONFIG_PM_TEST_SUSPEND
-
-/*
- * We test the system suspend code by setting an RTC wakealarm a short
- * time in the future, then suspending. Suspending the devices won't
- * normally take long ... some systems only need a few milliseconds.
- *
- * The time it takes is system-specific though, so when we test this
- * during system bootup we allow a LOT of time.
- */
-#define TEST_SUSPEND_SECONDS 5
-
-static unsigned long suspend_test_start_time;
-
-static void suspend_test_start(void)
-{
- /* FIXME Use better timebase than "jiffies", ideally a clocksource.
- * What we want is a hardware counter that will work correctly even
- * during the irqs-are-off stages of the suspend/resume cycle...
- */
- suspend_test_start_time = jiffies;
-}
-
-static void suspend_test_finish(const char *label)
-{
- long nj = jiffies - suspend_test_start_time;
- unsigned msec;
-
- msec = jiffies_to_msecs(abs(nj));
- pr_info("PM: %s took %d.%03d seconds\n", label,
- msec / 1000, msec % 1000);
-
- /* Warning on suspend means the RTC alarm period needs to be
- * larger -- the system was sooo slooowwww to suspend that the
- * alarm (should have) fired before the system went to sleep!
- *
- * Warning on either suspend or resume also means the system
- * has some performance issues. The stack dump of a WARN_ON
- * is more likely to get the right attention than a printk...
- */
- WARN(msec > (TEST_SUSPEND_SECONDS * 1000), "Component: %s\n", label);
-}
-
-#else
-
-static void suspend_test_start(void)
-{
-}
-
-static void suspend_test_finish(const char *label)
-{
-}
-
-#endif
-
-static struct platform_suspend_ops *suspend_ops;
-
-/**
- * suspend_set_ops - Set the global suspend method table.
- * @ops: Pointer to ops structure.
- */
-
-void suspend_set_ops(struct platform_suspend_ops *ops)
-{
- mutex_lock(&pm_mutex);
- suspend_ops = ops;
- mutex_unlock(&pm_mutex);
-}
-
-/**
- * suspend_valid_only_mem - generic memory-only valid callback
- *
- * Platform drivers that implement mem suspend only and only need
- * to check for that in their .valid callback can use this instead
- * of rolling their own .valid callback.
- */
-int suspend_valid_only_mem(suspend_state_t state)
-{
- return state == PM_SUSPEND_MEM;
-}
-
-/**
- * suspend_prepare - Do prep work before entering low-power state.
- *
- * This is common code that is called for each state that we're entering.
- * Run suspend notifiers, allocate a console and stop all processes.
- */
-static int suspend_prepare(void)
-{
- int error;
-
- if (!suspend_ops || !suspend_ops->enter)
- return -EPERM;
-
- pm_prepare_console();
-
- error = pm_notifier_call_chain(PM_SUSPEND_PREPARE);
- if (error)
- goto Finish;
-
- error = usermodehelper_disable();
- if (error)
- goto Finish;
-
- error = suspend_freeze_processes();
- if (!error)
- return 0;
-
- suspend_thaw_processes();
- usermodehelper_enable();
- Finish:
- pm_notifier_call_chain(PM_POST_SUSPEND);
- pm_restore_console();
- return error;
-}
-
-/* default implementation */
-void __attribute__ ((weak)) arch_suspend_disable_irqs(void)
-{
- local_irq_disable();
-}
-
-/* default implementation */
-void __attribute__ ((weak)) arch_suspend_enable_irqs(void)
-{
- local_irq_enable();
-}
-
-/**
- * suspend_enter - enter the desired system sleep state.
- * @state: state to enter
- *
- * This function should be called after devices have been suspended.
- */
-static int suspend_enter(suspend_state_t state)
-{
- int error;
-
- if (suspend_ops->prepare) {
- error = suspend_ops->prepare();
- if (error)
- return error;
- }
-
- error = dpm_suspend_noirq(PMSG_SUSPEND);
- if (error) {
- printk(KERN_ERR "PM: Some devices failed to power down\n");
- goto Platfrom_finish;
- }
-
- if (suspend_ops->prepare_late) {
- error = suspend_ops->prepare_late();
- if (error)
- goto Power_up_devices;
- }
-
- if (suspend_test(TEST_PLATFORM))
- goto Platform_wake;
-
- error = disable_nonboot_cpus();
- if (error || suspend_test(TEST_CPUS))
- goto Enable_cpus;
-
- arch_suspend_disable_irqs();
- BUG_ON(!irqs_disabled());
-
- error = sysdev_suspend(PMSG_SUSPEND);
- if (!error) {
- if (!suspend_test(TEST_CORE))
- error = suspend_ops->enter(state);
- sysdev_resume();
- }
-
- arch_suspend_enable_irqs();
- BUG_ON(irqs_disabled());
-
- Enable_cpus:
- enable_nonboot_cpus();
-
- Platform_wake:
- if (suspend_ops->wake)
- suspend_ops->wake();
-
- Power_up_devices:
- dpm_resume_noirq(PMSG_RESUME);
-
- Platfrom_finish:
- if (suspend_ops->finish)
- suspend_ops->finish();
-
- return error;
-}
-
-/**
- * suspend_devices_and_enter - suspend devices and enter the desired system
- * sleep state.
- * @state: state to enter
- */
-int suspend_devices_and_enter(suspend_state_t state)
-{
- int error;
-
- if (!suspend_ops)
- return -ENOSYS;
-
- if (suspend_ops->begin) {
- error = suspend_ops->begin(state);
- if (error)
- goto Close;
- }
- suspend_console();
- suspend_test_start();
- error = dpm_suspend_start(PMSG_SUSPEND);
- if (error) {
- printk(KERN_ERR "PM: Some devices failed to suspend\n");
- goto Recover_platform;
- }
- suspend_test_finish("suspend devices");
- if (suspend_test(TEST_DEVICES))
- goto Recover_platform;
-
- suspend_enter(state);
-
- Resume_devices:
- suspend_test_start();
- dpm_resume_end(PMSG_RESUME);
- suspend_test_finish("resume devices");
- resume_console();
- Close:
- if (suspend_ops->end)
- suspend_ops->end();
- return error;
-
- Recover_platform:
- if (suspend_ops->recover)
- suspend_ops->recover();
- goto Resume_devices;
-}
-
-/**
- * suspend_finish - Do final work before exiting suspend sequence.
- *
- * Call platform code to clean up, restart processes, and free the
- * console that we've allocated. This is not called for suspend-to-disk.
- */
-static void suspend_finish(void)
-{
- suspend_thaw_processes();
- usermodehelper_enable();
- pm_notifier_call_chain(PM_POST_SUSPEND);
- pm_restore_console();
-}
-
-
-
-
-static const char * const pm_states[PM_SUSPEND_MAX] = {
- [PM_SUSPEND_STANDBY] = "standby",
- [PM_SUSPEND_MEM] = "mem",
-};
-
-static inline int valid_state(suspend_state_t state)
-{
- /* All states need lowlevel support and need to be valid
- * to the lowlevel implementation, no valid callback
- * implies that none are valid. */
- if (!suspend_ops || !suspend_ops->valid || !suspend_ops->valid(state))
- return 0;
- return 1;
-}
-
-
-/**
- * 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(suspend_state_t state)
-{
- int error;
-
- if (!valid_state(state))
- return -ENODEV;
-
- if (!mutex_trylock(&pm_mutex))
- return -EBUSY;
-
- printk(KERN_INFO "PM: Syncing filesystems ... ");
- sys_sync();
- printk("done.\n");
-
- pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]);
- error = suspend_prepare();
- if (error)
- goto Unlock;
-
- if (suspend_test(TEST_FREEZER))
- goto Finish;
-
- pr_debug("PM: Entering %s sleep\n", pm_states[state]);
- error = suspend_devices_and_enter(state);
-
- Finish:
- pr_debug("PM: Finishing wakeup.\n");
- suspend_finish();
- Unlock:
- mutex_unlock(&pm_mutex);
- return error;
-}
-
-
-/**
- * pm_suspend - Externally visible function for suspending system.
- * @state: Enumerated value of state to enter.
- *
- * Determine whether or not value is within range, get state
- * structure, and enter (above).
- */
-
-int pm_suspend(suspend_state_t state)
-{
- if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX)
- return enter_state(state);
- return -EINVAL;
-}
-
-EXPORT_SYMBOL(pm_suspend);
-
-#endif /* CONFIG_SUSPEND */
-
struct kobject *power_kobj;
/**
* store() accepts one of those strings, translates it into the
* proper enumerated value, and initiates a suspend transition.
*/
-
static ssize_t state_show(struct kobject *kobj, struct kobj_attribute *attr,
char *buf)
{
.attrs = g,
};
-
static int __init pm_init(void)
{
power_kobj = kobject_create_and_add("power", NULL);
}
core_initcall(pm_init);
-
-
-#ifdef CONFIG_PM_TEST_SUSPEND
-
-#include <linux/rtc.h>
-
-/*
- * To test system suspend, we need a hands-off mechanism to resume the
- * system. RTCs wake alarms are a common self-contained mechanism.
- */
-
-static void __init test_wakealarm(struct rtc_device *rtc, suspend_state_t state)
-{
- static char err_readtime[] __initdata =
- KERN_ERR "PM: can't read %s time, err %d\n";
- static char err_wakealarm [] __initdata =
- KERN_ERR "PM: can't set %s wakealarm, err %d\n";
- static char err_suspend[] __initdata =
- KERN_ERR "PM: suspend test failed, error %d\n";
- static char info_test[] __initdata =
- KERN_INFO "PM: test RTC wakeup from '%s' suspend\n";
-
- unsigned long now;
- struct rtc_wkalrm alm;
- int status;
-
- /* this may fail if the RTC hasn't been initialized */
- status = rtc_read_time(rtc, &alm.time);
- if (status < 0) {
- printk(err_readtime, dev_name(&rtc->dev), status);
- return;
- }
- rtc_tm_to_time(&alm.time, &now);
-
- memset(&alm, 0, sizeof alm);
- rtc_time_to_tm(now + TEST_SUSPEND_SECONDS, &alm.time);
- alm.enabled = true;
-
- status = rtc_set_alarm(rtc, &alm);
- if (status < 0) {
- printk(err_wakealarm, dev_name(&rtc->dev), status);
- return;
- }
-
- if (state == PM_SUSPEND_MEM) {
- printk(info_test, pm_states[state]);
- status = pm_suspend(state);
- if (status == -ENODEV)
- state = PM_SUSPEND_STANDBY;
- }
- if (state == PM_SUSPEND_STANDBY) {
- printk(info_test, pm_states[state]);
- status = pm_suspend(state);
- }
- if (status < 0)
- printk(err_suspend, status);
-
- /* Some platforms can't detect that the alarm triggered the
- * wakeup, or (accordingly) disable it after it afterwards.
- * It's supposed to give oneshot behavior; cope.
- */
- alm.enabled = false;
- rtc_set_alarm(rtc, &alm);
-}
-
-static int __init has_wakealarm(struct device *dev, void *name_ptr)
-{
- struct rtc_device *candidate = to_rtc_device(dev);
-
- if (!candidate->ops->set_alarm)
- return 0;
- if (!device_may_wakeup(candidate->dev.parent))
- return 0;
-
- *(const char **)name_ptr = dev_name(dev);
- return 1;
-}
-
-/*
- * Kernel options like "test_suspend=mem" force suspend/resume sanity tests
- * at startup time. They're normally disabled, for faster boot and because
- * we can't know which states really work on this particular system.
- */
-static suspend_state_t test_state __initdata = PM_SUSPEND_ON;
-
-static char warn_bad_state[] __initdata =
- KERN_WARNING "PM: can't test '%s' suspend state\n";
-
-static int __init setup_test_suspend(char *value)
-{
- unsigned i;
-
- /* "=mem" ==> "mem" */
- value++;
- for (i = 0; i < PM_SUSPEND_MAX; i++) {
- if (!pm_states[i])
- continue;
- if (strcmp(pm_states[i], value) != 0)
- continue;
- test_state = (__force suspend_state_t) i;
- return 0;
- }
- printk(warn_bad_state, value);
- return 0;
-}
-__setup("test_suspend", setup_test_suspend);
-
-static int __init test_suspend(void)
-{
- static char warn_no_rtc[] __initdata =
- KERN_WARNING "PM: no wakealarm-capable RTC driver is ready\n";
-
- char *pony = NULL;
- struct rtc_device *rtc = NULL;
-
- /* PM is initialized by now; is that state testable? */
- if (test_state == PM_SUSPEND_ON)
- goto done;
- if (!valid_state(test_state)) {
- printk(warn_bad_state, pm_states[test_state]);
- goto done;
- }
-
- /* RTCs have initialized by now too ... can we use one? */
- class_find_device(rtc_class, NULL, &pony, has_wakealarm);
- if (pony)
- rtc = rtc_class_open(pony);
- if (!rtc) {
- printk(warn_no_rtc);
- goto done;
- }
-
- /* go for it */
- test_wakealarm(rtc, test_state);
- rtc_class_close(rtc);
-done:
- return 0;
-}
-late_initcall(test_suspend);
-
-#endif /* CONFIG_PM_TEST_SUSPEND */
unsigned int, char *);
#ifdef CONFIG_SUSPEND
-/* kernel/power/main.c */
+/* kernel/power/suspend.c */
+extern const char *const pm_states[];
+
+extern bool valid_state(suspend_state_t state);
extern int suspend_devices_and_enter(suspend_state_t state);
+extern int enter_state(suspend_state_t state);
#else /* !CONFIG_SUSPEND */
static inline int suspend_devices_and_enter(suspend_state_t state)
{
return -ENOSYS;
}
+static inline int enter_state(suspend_state_t state) { return -ENOSYS; }
+static inline bool valid_state(suspend_state_t state) { return false; }
#endif /* !CONFIG_SUSPEND */
+#ifdef CONFIG_PM_TEST_SUSPEND
+/* kernel/power/suspend_test.c */
+extern void suspend_test_start(void);
+extern void suspend_test_finish(const char *label);
+#else /* !CONFIG_PM_TEST_SUSPEND */
+static inline void suspend_test_start(void) {}
+static inline void suspend_test_finish(const char *label) {}
+#endif /* !CONFIG_PM_TEST_SUSPEND */
+
#ifdef CONFIG_PM_SLEEP
/* kernel/power/main.c */
extern int pm_notifier_call_chain(unsigned long val);
--- /dev/null
+/*
+ * kernel/power/suspend.c - Suspend to RAM and standby functionality.
+ *
+ * Copyright (c) 2003 Patrick Mochel
+ * Copyright (c) 2003 Open Source Development Lab
+ * Copyright (c) 2009 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc.
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/string.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/cpu.h>
+#include <linux/syscalls.h>
+
+#include "power.h"
+
+const char *const pm_states[PM_SUSPEND_MAX] = {
+ [PM_SUSPEND_STANDBY] = "standby",
+ [PM_SUSPEND_MEM] = "mem",
+};
+
+static struct platform_suspend_ops *suspend_ops;
+
+/**
+ * suspend_set_ops - Set the global suspend method table.
+ * @ops: Pointer to ops structure.
+ */
+void suspend_set_ops(struct platform_suspend_ops *ops)
+{
+ mutex_lock(&pm_mutex);
+ suspend_ops = ops;
+ mutex_unlock(&pm_mutex);
+}
+
+bool valid_state(suspend_state_t state)
+{
+ /*
+ * All states need lowlevel support and need to be valid to the lowlevel
+ * implementation, no valid callback implies that none are valid.
+ */
+ return suspend_ops && suspend_ops->valid && suspend_ops->valid(state);
+}
+
+/**
+ * suspend_valid_only_mem - generic memory-only valid callback
+ *
+ * Platform drivers that implement mem suspend only and only need
+ * to check for that in their .valid callback can use this instead
+ * of rolling their own .valid callback.
+ */
+int suspend_valid_only_mem(suspend_state_t state)
+{
+ return state == PM_SUSPEND_MEM;
+}
+
+static int suspend_test(int level)
+{
+#ifdef CONFIG_PM_DEBUG
+ if (pm_test_level == level) {
+ printk(KERN_INFO "suspend debug: Waiting for 5 seconds.\n");
+ mdelay(5000);
+ return 1;
+ }
+#endif /* !CONFIG_PM_DEBUG */
+ return 0;
+}
+
+/**
+ * suspend_prepare - Do prep work before entering low-power state.
+ *
+ * This is common code that is called for each state that we're entering.
+ * Run suspend notifiers, allocate a console and stop all processes.
+ */
+static int suspend_prepare(void)
+{
+ int error;
+
+ if (!suspend_ops || !suspend_ops->enter)
+ return -EPERM;
+
+ pm_prepare_console();
+
+ error = pm_notifier_call_chain(PM_SUSPEND_PREPARE);
+ if (error)
+ goto Finish;
+
+ error = usermodehelper_disable();
+ if (error)
+ goto Finish;
+
+ error = suspend_freeze_processes();
+ if (!error)
+ return 0;
+
+ suspend_thaw_processes();
+ usermodehelper_enable();
+ Finish:
+ pm_notifier_call_chain(PM_POST_SUSPEND);
+ pm_restore_console();
+ return error;
+}
+
+/* default implementation */
+void __attribute__ ((weak)) arch_suspend_disable_irqs(void)
+{
+ local_irq_disable();
+}
+
+/* default implementation */
+void __attribute__ ((weak)) arch_suspend_enable_irqs(void)
+{
+ local_irq_enable();
+}
+
+/**
+ * suspend_enter - enter the desired system sleep state.
+ * @state: state to enter
+ *
+ * This function should be called after devices have been suspended.
+ */
+static int suspend_enter(suspend_state_t state)
+{
+ int error;
+
+ if (suspend_ops->prepare) {
+ error = suspend_ops->prepare();
+ if (error)
+ return error;
+ }
+
+ error = dpm_suspend_noirq(PMSG_SUSPEND);
+ if (error) {
+ printk(KERN_ERR "PM: Some devices failed to power down\n");
+ goto Platfrom_finish;
+ }
+
+ if (suspend_ops->prepare_late) {
+ error = suspend_ops->prepare_late();
+ if (error)
+ goto Power_up_devices;
+ }
+
+ if (suspend_test(TEST_PLATFORM))
+ goto Platform_wake;
+
+ error = disable_nonboot_cpus();
+ if (error || suspend_test(TEST_CPUS))
+ goto Enable_cpus;
+
+ arch_suspend_disable_irqs();
+ BUG_ON(!irqs_disabled());
+
+ error = sysdev_suspend(PMSG_SUSPEND);
+ if (!error) {
+ if (!suspend_test(TEST_CORE))
+ error = suspend_ops->enter(state);
+ sysdev_resume();
+ }
+
+ arch_suspend_enable_irqs();
+ BUG_ON(irqs_disabled());
+
+ Enable_cpus:
+ enable_nonboot_cpus();
+
+ Platform_wake:
+ if (suspend_ops->wake)
+ suspend_ops->wake();
+
+ Power_up_devices:
+ dpm_resume_noirq(PMSG_RESUME);
+
+ Platfrom_finish:
+ if (suspend_ops->finish)
+ suspend_ops->finish();
+
+ return error;
+}
+
+/**
+ * suspend_devices_and_enter - suspend devices and enter the desired system
+ * sleep state.
+ * @state: state to enter
+ */
+int suspend_devices_and_enter(suspend_state_t state)
+{
+ int error;
+
+ if (!suspend_ops)
+ return -ENOSYS;
+
+ if (suspend_ops->begin) {
+ error = suspend_ops->begin(state);
+ if (error)
+ goto Close;
+ }
+ suspend_console();
+ suspend_test_start();
+ error = dpm_suspend_start(PMSG_SUSPEND);
+ if (error) {
+ printk(KERN_ERR "PM: Some devices failed to suspend\n");
+ goto Recover_platform;
+ }
+ suspend_test_finish("suspend devices");
+ if (suspend_test(TEST_DEVICES))
+ goto Recover_platform;
+
+ suspend_enter(state);
+
+ Resume_devices:
+ suspend_test_start();
+ dpm_resume_end(PMSG_RESUME);
+ suspend_test_finish("resume devices");
+ resume_console();
+ Close:
+ if (suspend_ops->end)
+ suspend_ops->end();
+ return error;
+
+ Recover_platform:
+ if (suspend_ops->recover)
+ suspend_ops->recover();
+ goto Resume_devices;
+}
+
+/**
+ * suspend_finish - Do final work before exiting suspend sequence.
+ *
+ * Call platform code to clean up, restart processes, and free the
+ * console that we've allocated. This is not called for suspend-to-disk.
+ */
+static void suspend_finish(void)
+{
+ suspend_thaw_processes();
+ usermodehelper_enable();
+ pm_notifier_call_chain(PM_POST_SUSPEND);
+ 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).
+ */
+int enter_state(suspend_state_t state)
+{
+ int error;
+
+ if (!valid_state(state))
+ return -ENODEV;
+
+ if (!mutex_trylock(&pm_mutex))
+ return -EBUSY;
+
+ printk(KERN_INFO "PM: Syncing filesystems ... ");
+ sys_sync();
+ printk("done.\n");
+
+ pr_debug("PM: Preparing system for %s sleep\n", pm_states[state]);
+ error = suspend_prepare();
+ if (error)
+ goto Unlock;
+
+ if (suspend_test(TEST_FREEZER))
+ goto Finish;
+
+ pr_debug("PM: Entering %s sleep\n", pm_states[state]);
+ error = suspend_devices_and_enter(state);
+
+ Finish:
+ pr_debug("PM: Finishing wakeup.\n");
+ suspend_finish();
+ Unlock:
+ mutex_unlock(&pm_mutex);
+ return error;
+}
+
+/**
+ * pm_suspend - Externally visible function for suspending system.
+ * @state: Enumerated value of state to enter.
+ *
+ * Determine whether or not value is within range, get state
+ * structure, and enter (above).
+ */
+int pm_suspend(suspend_state_t state)
+{
+ if (state > PM_SUSPEND_ON && state <= PM_SUSPEND_MAX)
+ return enter_state(state);
+ return -EINVAL;
+}
+EXPORT_SYMBOL(pm_suspend);
--- /dev/null
+/*
+ * kernel/power/suspend_test.c - Suspend to RAM and standby test facility.
+ *
+ * Copyright (c) 2009 Pavel Machek <pavel@ucw.cz>
+ *
+ * This file is released under the GPLv2.
+ */
+
+#include <linux/init.h>
+#include <linux/rtc.h>
+
+#include "power.h"
+
+/*
+ * We test the system suspend code by setting an RTC wakealarm a short
+ * time in the future, then suspending. Suspending the devices won't
+ * normally take long ... some systems only need a few milliseconds.
+ *
+ * The time it takes is system-specific though, so when we test this
+ * during system bootup we allow a LOT of time.
+ */
+#define TEST_SUSPEND_SECONDS 5
+
+static unsigned long suspend_test_start_time;
+
+void suspend_test_start(void)
+{
+ /* FIXME Use better timebase than "jiffies", ideally a clocksource.
+ * What we want is a hardware counter that will work correctly even
+ * during the irqs-are-off stages of the suspend/resume cycle...
+ */
+ suspend_test_start_time = jiffies;
+}
+
+void suspend_test_finish(const char *label)
+{
+ long nj = jiffies - suspend_test_start_time;
+ unsigned msec;
+
+ msec = jiffies_to_msecs(abs(nj));
+ pr_info("PM: %s took %d.%03d seconds\n", label,
+ msec / 1000, msec % 1000);
+
+ /* Warning on suspend means the RTC alarm period needs to be
+ * larger -- the system was sooo slooowwww to suspend that the
+ * alarm (should have) fired before the system went to sleep!
+ *
+ * Warning on either suspend or resume also means the system
+ * has some performance issues. The stack dump of a WARN_ON
+ * is more likely to get the right attention than a printk...
+ */
+ WARN(msec > (TEST_SUSPEND_SECONDS * 1000), "Component: %s\n", label);
+}
+
+/*
+ * To test system suspend, we need a hands-off mechanism to resume the
+ * system. RTCs wake alarms are a common self-contained mechanism.
+ */
+
+static void __init test_wakealarm(struct rtc_device *rtc, suspend_state_t state)
+{
+ static char err_readtime[] __initdata =
+ KERN_ERR "PM: can't read %s time, err %d\n";
+ static char err_wakealarm [] __initdata =
+ KERN_ERR "PM: can't set %s wakealarm, err %d\n";
+ static char err_suspend[] __initdata =
+ KERN_ERR "PM: suspend test failed, error %d\n";
+ static char info_test[] __initdata =
+ KERN_INFO "PM: test RTC wakeup from '%s' suspend\n";
+
+ unsigned long now;
+ struct rtc_wkalrm alm;
+ int status;
+
+ /* this may fail if the RTC hasn't been initialized */
+ status = rtc_read_time(rtc, &alm.time);
+ if (status < 0) {
+ printk(err_readtime, dev_name(&rtc->dev), status);
+ return;
+ }
+ rtc_tm_to_time(&alm.time, &now);
+
+ memset(&alm, 0, sizeof alm);
+ rtc_time_to_tm(now + TEST_SUSPEND_SECONDS, &alm.time);
+ alm.enabled = true;
+
+ status = rtc_set_alarm(rtc, &alm);
+ if (status < 0) {
+ printk(err_wakealarm, dev_name(&rtc->dev), status);
+ return;
+ }
+
+ if (state == PM_SUSPEND_MEM) {
+ printk(info_test, pm_states[state]);
+ status = pm_suspend(state);
+ if (status == -ENODEV)
+ state = PM_SUSPEND_STANDBY;
+ }
+ if (state == PM_SUSPEND_STANDBY) {
+ printk(info_test, pm_states[state]);
+ status = pm_suspend(state);
+ }
+ if (status < 0)
+ printk(err_suspend, status);
+
+ /* Some platforms can't detect that the alarm triggered the
+ * wakeup, or (accordingly) disable it after it afterwards.
+ * It's supposed to give oneshot behavior; cope.
+ */
+ alm.enabled = false;
+ rtc_set_alarm(rtc, &alm);
+}
+
+static int __init has_wakealarm(struct device *dev, void *name_ptr)
+{
+ struct rtc_device *candidate = to_rtc_device(dev);
+
+ if (!candidate->ops->set_alarm)
+ return 0;
+ if (!device_may_wakeup(candidate->dev.parent))
+ return 0;
+
+ *(const char **)name_ptr = dev_name(dev);
+ return 1;
+}
+
+/*
+ * Kernel options like "test_suspend=mem" force suspend/resume sanity tests
+ * at startup time. They're normally disabled, for faster boot and because
+ * we can't know which states really work on this particular system.
+ */
+static suspend_state_t test_state __initdata = PM_SUSPEND_ON;
+
+static char warn_bad_state[] __initdata =
+ KERN_WARNING "PM: can't test '%s' suspend state\n";
+
+static int __init setup_test_suspend(char *value)
+{
+ unsigned i;
+
+ /* "=mem" ==> "mem" */
+ value++;
+ for (i = 0; i < PM_SUSPEND_MAX; i++) {
+ if (!pm_states[i])
+ continue;
+ if (strcmp(pm_states[i], value) != 0)
+ continue;
+ test_state = (__force suspend_state_t) i;
+ return 0;
+ }
+ printk(warn_bad_state, value);
+ return 0;
+}
+__setup("test_suspend", setup_test_suspend);
+
+static int __init test_suspend(void)
+{
+ static char warn_no_rtc[] __initdata =
+ KERN_WARNING "PM: no wakealarm-capable RTC driver is ready\n";
+
+ char *pony = NULL;
+ struct rtc_device *rtc = NULL;
+
+ /* PM is initialized by now; is that state testable? */
+ if (test_state == PM_SUSPEND_ON)
+ goto done;
+ if (!valid_state(test_state)) {
+ printk(warn_bad_state, pm_states[test_state]);
+ goto done;
+ }
+
+ /* RTCs have initialized by now too ... can we use one? */
+ class_find_device(rtc_class, NULL, &pony, has_wakealarm);
+ if (pony)
+ rtc = rtc_class_open(pony);
+ if (!rtc) {
+ printk(warn_no_rtc);
+ goto done;
+ }
+
+ /* go for it */
+ test_wakealarm(rtc, test_state);
+ rtc_class_close(rtc);
+done:
+ return 0;
+}
+late_initcall(test_suspend);
projects / GitHub / MotorolaMobilityLLC / kernel-slsi.git / commitdiff