diff options
Diffstat (limited to 'Documentation/power/devices.txt')
-rw-r--r-- | Documentation/power/devices.txt | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt index c53d263..461e4f1 100644 --- a/Documentation/power/devices.txt +++ b/Documentation/power/devices.txt @@ -310,9 +310,12 @@ used with suspend-to-disk: PM_EVENT_SUSPEND -- quiesce the driver and put hardware into a low-power state. When used with system sleep states like "suspend-to-RAM" or "standby", the upcoming resume() call will often be able to rely on - state kept in hardware, or issue system wakeup events. When used - instead with suspend-to-disk, few devices support this capability; - most are completely powered off. + state kept in hardware, or issue system wakeup events. + + PM_EVENT_HIBERNATE -- Put hardware into a low-power state and enable wakeup + events as appropriate. It is only used with hibernation + (suspend-to-disk) and few devices are able to wake up the system from + this state; most are completely powered off. PM_EVENT_FREEZE -- quiesce the driver, but don't necessarily change into any low power mode. A system snapshot is about to be taken, often @@ -329,8 +332,8 @@ used with suspend-to-disk: wakeup events nor DMA are allowed. To enter "standby" (ACPI S1) or "Suspend to RAM" (STR, ACPI S3) states, or -the similarly named APM states, only PM_EVENT_SUSPEND is used; for "Suspend -to Disk" (STD, hibernate, ACPI S4), all of those event codes are used. +the similarly named APM states, only PM_EVENT_SUSPEND is used; the other event +codes are used for hibernation ("Suspend to Disk", STD, ACPI S4). There's also PM_EVENT_ON, a value which never appears as a suspend event but is sometimes used to record the "not suspended" device state. |