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Diffstat (limited to 'kernel/Documentation/power/devices.txt')
| -rw-r--r-- | kernel/Documentation/power/devices.txt | 7 |
1 files changed, 7 insertions, 0 deletions
diff --git a/kernel/Documentation/power/devices.txt b/kernel/Documentation/power/devices.txt index d172bce0f..8ba6625fd 100644 --- a/kernel/Documentation/power/devices.txt +++ b/kernel/Documentation/power/devices.txt @@ -341,6 +341,13 @@ the phases are: and is entirely responsible for bringing the device back to the functional state as appropriate. + Note that this direct-complete procedure applies even if the device is + disabled for runtime PM; only the runtime-PM status matters. It follows + that if a device has system-sleep callbacks but does not support runtime + PM, then its prepare callback must never return a positive value. This + is because all devices are initially set to runtime-suspended with + runtime PM disabled. + 2. The suspend methods should quiesce the device to stop it from performing I/O. They also may save the device registers and put it into the appropriate low-power state, depending on the bus type the device is on, |