Merge back earlier suspend/hibernate material for v4.1.

Documentation/kernel-parameters.txt

@@ -3462,6 +3462,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			improve throughput, but will also increase the
 			amount of memory reserved for use by the client.
 
+	suspend.pm_test_delay=
+			[SUSPEND]
+			Sets the number of seconds to remain in a suspend test
+			mode before resuming the system (see
+			/sys/power/pm_test). Only available when CONFIG_PM_DEBUG
+			is set. Default value is 5.
+
 	swapaccount=[0|1]
 			[KNL] Enable accounting of swap in memory resource
 			controller if no parameter or 1 is given or disable

Documentation/power/basic-pm-debugging.txt

@@ -75,12 +75,14 @@ you should do the following:
 # echo platform > /sys/power/disk
 # echo disk > /sys/power/state
 
-Then, the kernel will try to freeze processes, suspend devices, wait 5 seconds,
-resume devices and thaw processes.  If "platform" is written to
+Then, the kernel will try to freeze processes, suspend devices, wait a few
+seconds (5 by default, but configurable by the suspend.pm_test_delay module
+parameter), resume devices and thaw processes.  If "platform" is written to
 /sys/power/pm_test , then after suspending devices the kernel will additionally
 invoke the global control methods (eg. ACPI global control methods) used to
-prepare the platform firmware for hibernation.  Next, it will wait 5 seconds and
-invoke the platform (eg. ACPI) global methods used to cancel hibernation etc.
+prepare the platform firmware for hibernation.  Next, it will wait a
+configurable number of seconds and invoke the platform (eg. ACPI) global
+methods used to cancel hibernation etc.
 
 Writing "none" to /sys/power/pm_test causes the kernel to switch to the normal
 hibernation/suspend operations.  Also, when open for reading, /sys/power/pm_test

arch/x86/include/asm/resume-trace.h → arch/x86/include/asm/pm-trace.h

@@ -1,5 +1,5 @@
-#ifndef _ASM_X86_RESUME_TRACE_H
-#define _ASM_X86_RESUME_TRACE_H
+#ifndef _ASM_X86_PM_TRACE_H
+#define _ASM_X86_PM_TRACE_H
 
 #include <asm/asm.h>
 
@@ -14,8 +14,10 @@ do {								\
 			     ".previous"			\
 			     :"=r" (tracedata)			\
 			     : "i" (__LINE__), "i" (__FILE__));	\
-		generate_resume_trace(tracedata, user);		\
+		generate_pm_trace(tracedata, user);		\
 	}							\
 } while (0)
 
-#endif /* _ASM_X86_RESUME_TRACE_H */
+#define TRACE_SUSPEND(user)	TRACE_RESUME(user)
+
+#endif /* _ASM_X86_PM_TRACE_H */

drivers/base/power/main.c

@@ -23,7 +23,7 @@
 #include <linux/mutex.h>
 #include <linux/pm.h>
 #include <linux/pm_runtime.h>
-#include <linux/resume-trace.h>
+#include <linux/pm-trace.h>
 #include <linux/interrupt.h>
 #include <linux/sched.h>
 #include <linux/async.h>
@@ -1017,6 +1017,9 @@ static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool a
 	char *info = NULL;
 	int error = 0;
 
+	TRACE_DEVICE(dev);
+	TRACE_SUSPEND(0);
+
 	if (async_error)
 		goto Complete;
 
@@ -1057,6 +1060,7 @@ static int __device_suspend_noirq(struct device *dev, pm_message_t state, bool a
 
 Complete:
 	complete_all(&dev->power.completion);
+	TRACE_SUSPEND(error);
 	return error;
 }
 
@@ -1078,7 +1082,7 @@ static int device_suspend_noirq(struct device *dev)
 {
 	reinit_completion(&dev->power.completion);
 
-	if (pm_async_enabled && dev->power.async_suspend) {
+	if (is_async(dev)) {
 		get_device(dev);
 		async_schedule(async_suspend_noirq, dev);
 		return 0;
@@ -1157,6 +1161,9 @@ static int __device_suspend_late(struct device *dev, pm_message_t state, bool as
 	char *info = NULL;
 	int error = 0;
 
+	TRACE_DEVICE(dev);
+	TRACE_SUSPEND(0);
+
 	__pm_runtime_disable(dev, false);
 
 	if (async_error)
@@ -1198,6 +1205,7 @@ static int __device_suspend_late(struct device *dev, pm_message_t state, bool as
 		async_error = error;
 
 Complete:
+	TRACE_SUSPEND(error);
 	complete_all(&dev->power.completion);
 	return error;
 }
@@ -1219,7 +1227,7 @@ static int device_suspend_late(struct device *dev)
 {
 	reinit_completion(&dev->power.completion);
 
-	if (pm_async_enabled && dev->power.async_suspend) {
+	if (is_async(dev)) {
 		get_device(dev);
 		async_schedule(async_suspend_late, dev);
 		return 0;
@@ -1338,6 +1346,9 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
 	int error = 0;
 	DECLARE_DPM_WATCHDOG_ON_STACK(wd);
 
+	TRACE_DEVICE(dev);
+	TRACE_SUSPEND(0);
+
 	dpm_wait_for_children(dev, async);
 
 	if (async_error)
@@ -1444,6 +1455,7 @@ static int __device_suspend(struct device *dev, pm_message_t state, bool async)
 	if (error)
 		async_error = error;
 
+	TRACE_SUSPEND(error);
 	return error;
 }
 
@@ -1465,7 +1477,7 @@ static int device_suspend(struct device *dev)
 {
 	reinit_completion(&dev->power.completion);
 
-	if (pm_async_enabled && dev->power.async_suspend) {
+	if (is_async(dev)) {
 		get_device(dev);
 		async_schedule(async_suspend, dev);
 		return 0;

drivers/base/power/trace.c

@@ -7,7 +7,7 @@
  * devices may be working.
  */
 
-#include <linux/resume-trace.h>
+#include <linux/pm-trace.h>
 #include <linux/export.h>
 #include <linux/rtc.h>
 
@@ -154,7 +154,7 @@ EXPORT_SYMBOL(set_trace_device);
  * it's not any guarantee, but it's a high _likelihood_ that
  * the match is valid).
  */
-void generate_resume_trace(const void *tracedata, unsigned int user)
+void generate_pm_trace(const void *tracedata, unsigned int user)
 {
 	unsigned short lineno = *(unsigned short *)tracedata;
 	const char *file = *(const char **)(tracedata + 2);
@@ -164,7 +164,7 @@ void generate_resume_trace(const void *tracedata, unsigned int user)
 	file_hash_value = hash_string(lineno, file, FILEHASH);
 	set_magic_time(user_hash_value, file_hash_value, dev_hash_value);
 }
-EXPORT_SYMBOL(generate_resume_trace);
+EXPORT_SYMBOL(generate_pm_trace);
 
 extern char __tracedata_start, __tracedata_end;
 static int show_file_hash(unsigned int value)

drivers/watchdog/iTCO_wdt.c

@@ -51,6 +51,7 @@
 #define DRV_VERSION	"1.11"
 
 /* Includes */
+#include <linux/acpi.h>			/* For ACPI support */
 #include <linux/module.h>		/* For module specific items */
 #include <linux/moduleparam.h>		/* For new moduleparam's */
 #include <linux/types.h>		/* For standard types (like size_t) */
@@ -103,6 +104,8 @@ static struct {		/* this is private data for the iTCO_wdt device */
 	struct platform_device *dev;
 	/* the PCI-device */
 	struct pci_dev *pdev;
+	/* whether or not the watchdog has been suspended */
+	bool suspended;
 } iTCO_wdt_private;
 
 /* module parameters */
@@ -571,12 +574,60 @@ static void iTCO_wdt_shutdown(struct platform_device *dev)
 	iTCO_wdt_stop(NULL);
 }
 
+#ifdef CONFIG_PM_SLEEP
+/*
+ * Suspend-to-idle requires this, because it stops the ticks and timekeeping, so
+ * the watchdog cannot be pinged while in that state.  In ACPI sleep states the
+ * watchdog is stopped by the platform firmware.
+ */
+
+#ifdef CONFIG_ACPI
+static inline bool need_suspend(void)
+{
+	return acpi_target_system_state() == ACPI_STATE_S0;
+}
+#else
+static inline bool need_suspend(void) { return true; }
+#endif
+
+static int iTCO_wdt_suspend_noirq(struct device *dev)
+{
+	int ret = 0;
+
+	iTCO_wdt_private.suspended = false;
+	if (watchdog_active(&iTCO_wdt_watchdog_dev) && need_suspend()) {
+		ret = iTCO_wdt_stop(&iTCO_wdt_watchdog_dev);
+		if (!ret)
+			iTCO_wdt_private.suspended = true;
+	}
+	return ret;
+}
+
+static int iTCO_wdt_resume_noirq(struct device *dev)
+{
+	if (iTCO_wdt_private.suspended)
+		iTCO_wdt_start(&iTCO_wdt_watchdog_dev);
+
+	return 0;
+}
+
+static struct dev_pm_ops iTCO_wdt_pm = {
+	.suspend_noirq = iTCO_wdt_suspend_noirq,
+	.resume_noirq = iTCO_wdt_resume_noirq,
+};
+
+#define ITCO_WDT_PM_OPS	(&iTCO_wdt_pm)
+#else
+#define ITCO_WDT_PM_OPS	NULL
+#endif /* CONFIG_PM_SLEEP */
+
 static struct platform_driver iTCO_wdt_driver = {
 	.probe          = iTCO_wdt_probe,
 	.remove         = iTCO_wdt_remove,
 	.shutdown       = iTCO_wdt_shutdown,
 	.driver         = {
 		.name   = DRV_NAME,
+		.pm     = ITCO_WDT_PM_OPS,
 	},
 };
 

include/linux/resume-trace.h → include/linux/pm-trace.h

@@ -1,8 +1,8 @@
-#ifndef RESUME_TRACE_H
-#define RESUME_TRACE_H
+#ifndef PM_TRACE_H
+#define PM_TRACE_H
 
 #ifdef CONFIG_PM_TRACE
-#include <asm/resume-trace.h>
+#include <asm/pm-trace.h>
 #include <linux/types.h>
 
 extern int pm_trace_enabled;
@@ -14,7 +14,7 @@ static inline int pm_trace_is_enabled(void)
 
 struct device;
 extern void set_trace_device(struct device *);
-extern void generate_resume_trace(const void *tracedata, unsigned int user);
+extern void generate_pm_trace(const void *tracedata, unsigned int user);
 extern int show_trace_dev_match(char *buf, size_t size);
 
 #define TRACE_DEVICE(dev) do { \
@@ -28,6 +28,7 @@ static inline int pm_trace_is_enabled(void) { return 0; }
 
 #define TRACE_DEVICE(dev) do { } while (0)
 #define TRACE_RESUME(dev) do { } while (0)
+#define TRACE_SUSPEND(dev) do { } while (0)
 
 #endif
 

kernel/power/main.c

@@ -11,7 +11,7 @@
 #include <linux/export.h>
 #include <linux/kobject.h>
 #include <linux/string.h>
-#include <linux/resume-trace.h>
+#include <linux/pm-trace.h>
 #include <linux/workqueue.h>
 #include <linux/debugfs.h>
 #include <linux/seq_file.h>

kernel/power/suspend.c

@@ -28,6 +28,7 @@
 #include <linux/ftrace.h>
 #include <trace/events/power.h>
 #include <linux/compiler.h>
+#include <linux/moduleparam.h>
 
 #include "power.h"
 
@@ -233,12 +234,20 @@ static bool platform_suspend_again(suspend_state_t state)
 		suspend_ops->suspend_again() : false;
 }
 
+#ifdef CONFIG_PM_DEBUG
+static unsigned int pm_test_delay = 5;
+module_param(pm_test_delay, uint, 0644);
+MODULE_PARM_DESC(pm_test_delay,
+		 "Number of seconds to wait before resuming from suspend test");
+#endif
+
 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);
+		printk(KERN_INFO "suspend debug: Waiting for %d second(s).\n",
+				pm_test_delay);
+		mdelay(pm_test_delay * 1000);
 		return 1;
 	}
 #endif /* !CONFIG_PM_DEBUG */