1 files changed, 45 insertions, 0 deletions

diff --git a/kernel/power/main.c b/kernel/power/main.c
index 428f8a034e96..f458238109cc 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -235,6 +235,47 @@ late_initcall(pm_debugfs_init);
 
 #endif /* CONFIG_PM_SLEEP */
 
+#ifdef CONFIG_PM_SLEEP_DEBUG
+/*
+ * pm_print_times: print time taken by devices to suspend and resume.
+ *
+ * show() returns whether printing of suspend and resume times is enabled.
+ * store() accepts 0 or 1.  0 disables printing and 1 enables it.
+ */
+bool pm_print_times_enabled;
+
+static ssize_t pm_print_times_show(struct kobject *kobj,
+                                   struct kobj_attribute *attr, char *buf)
+{
+        return sprintf(buf, "%d\n", pm_print_times_enabled);
+}
+
+static ssize_t pm_print_times_store(struct kobject *kobj,
+                                    struct kobj_attribute *attr,
+                                    const char *buf, size_t n)
+{
+        unsigned long val;
+
+        if (kstrtoul(buf, 10, &val))
+                return -EINVAL;
+
+        if (val > 1)
+                return -EINVAL;
+
+        pm_print_times_enabled = !!val;
+        return n;
+}
+
+power_attr(pm_print_times);
+
+static inline void pm_print_times_init(void)
+{
+        pm_print_times_enabled = !!initcall_debug;
+}
+#else /* !CONFIG_PP_SLEEP_DEBUG */
+static inline void pm_print_times_init(void) {}
+#endif /* CONFIG_PM_SLEEP_DEBUG */
+
 struct kobject *power_kobj;
 
 /**
@@ -531,6 +572,9 @@ static struct attribute * g[] = {
 #ifdef CONFIG_PM_DEBUG
         &pm_test_attr.attr,
 #endif
+#ifdef CONFIG_PM_SLEEP_DEBUG
+        &pm_print_times_attr.attr,
+#endif
 #endif
         NULL,
 };
@@ -566,6 +610,7 @@ static int __init pm_init(void)
         error = sysfs_create_group(power_kobj, &attr_group);
         if (error)
                 return error;
+        pm_print_times_init();
         return pm_autosleep_init();
 }