diff options
-rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 12 | ||||
-rw-r--r-- | kernel/power/main.c | 9 |
2 files changed, 21 insertions, 0 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index f1f2c0874da9..06beacf208de 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -5000,6 +5000,18 @@ that number, otherwise (e.g., 'pmu_override=on'), MMCR1 remains 0. + pm_async= [PM] + Format: off + This parameter sets the initial value of the + /sys/power/pm_async sysfs knob at boot time. + If set to "off", disables asynchronous suspend and + resume of devices during system-wide power transitions. + This can be useful on platforms where device + dependencies are not well-defined, or for debugging + power management issues. Asynchronous operations are + enabled by default. + + pm_debug_messages [SUSPEND,KNL] Enable suspend/resume debug messages during boot up. diff --git a/kernel/power/main.c b/kernel/power/main.c index 3d484630505a..3cf2d7e72567 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -8,6 +8,7 @@ #include <linux/acpi.h> #include <linux/export.h> +#include <linux/init.h> #include <linux/kobject.h> #include <linux/string.h> #include <linux/pm-trace.h> @@ -112,6 +113,14 @@ int pm_notifier_call_chain(unsigned long val) /* If set, devices may be suspended and resumed asynchronously. */ int pm_async_enabled = 1; +static int __init pm_async_setup(char *str) +{ + if (!strcmp(str, "off")) + pm_async_enabled = 0; + return 1; +} +__setup("pm_async=", pm_async_setup); + static ssize_t pm_async_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) { |