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 c53d26361919..461e4f1dbec4 100644 --- a/Documentation/power/devices.txt +++ b/Documentation/power/devices.txt | |||
@@ -310,9 +310,12 @@ used with suspend-to-disk: | |||
310 | PM_EVENT_SUSPEND -- quiesce the driver and put hardware into a low-power | 310 | PM_EVENT_SUSPEND -- quiesce the driver and put hardware into a low-power |
311 | state. When used with system sleep states like "suspend-to-RAM" or | 311 | state. When used with system sleep states like "suspend-to-RAM" or |
312 | "standby", the upcoming resume() call will often be able to rely on | 312 | "standby", the upcoming resume() call will often be able to rely on |
313 | state kept in hardware, or issue system wakeup events. When used | 313 | state kept in hardware, or issue system wakeup events. |
314 | instead with suspend-to-disk, few devices support this capability; | 314 | |
315 | most are completely powered off. | 315 | PM_EVENT_HIBERNATE -- Put hardware into a low-power state and enable wakeup |
316 | events as appropriate. It is only used with hibernation | ||
317 | (suspend-to-disk) and few devices are able to wake up the system from | ||
318 | this state; most are completely powered off. | ||
316 | 319 | ||
317 | PM_EVENT_FREEZE -- quiesce the driver, but don't necessarily change into | 320 | PM_EVENT_FREEZE -- quiesce the driver, but don't necessarily change into |
318 | any low power mode. A system snapshot is about to be taken, often | 321 | any low power mode. A system snapshot is about to be taken, often |
@@ -329,8 +332,8 @@ used with suspend-to-disk: | |||
329 | wakeup events nor DMA are allowed. | 332 | wakeup events nor DMA are allowed. |
330 | 333 | ||
331 | To enter "standby" (ACPI S1) or "Suspend to RAM" (STR, ACPI S3) states, or | 334 | To enter "standby" (ACPI S1) or "Suspend to RAM" (STR, ACPI S3) states, or |
332 | the similarly named APM states, only PM_EVENT_SUSPEND is used; for "Suspend | 335 | the similarly named APM states, only PM_EVENT_SUSPEND is used; the other event |
333 | to Disk" (STD, hibernate, ACPI S4), all of those event codes are used. | 336 | codes are used for hibernation ("Suspend to Disk", STD, ACPI S4). |
334 | 337 | ||
335 | There's also PM_EVENT_ON, a value which never appears as a suspend event | 338 | There's also PM_EVENT_ON, a value which never appears as a suspend event |
336 | but is sometimes used to record the "not suspended" device state. | 339 | but is sometimes used to record the "not suspended" device state. |