diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/power/devices.txt | 26 |
1 files changed, 0 insertions, 26 deletions
diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt index 88880839ece4..ff923fe67d98 100644 --- a/Documentation/power/devices.txt +++ b/Documentation/power/devices.txt @@ -549,32 +549,6 @@ callbacks. The other platforms need not implement it or take it into account in any way. -System Devices --------------- -System devices (sysdevs) follow a slightly different API, which can be found in - - include/linux/sysdev.h - drivers/base/sys.c - -System devices will be suspended with interrupts disabled, and after all other -devices have been suspended. On resume, they will be resumed before any other -devices, and also with interrupts disabled. These things occur in special -"sysdev_driver" phases, which affect only system devices. - -Thus, after the suspend_noirq (or freeze_noirq or poweroff_noirq) phase, when -the non-boot CPUs are all offline and IRQs are disabled on the remaining online -CPU, then a sysdev_driver.suspend phase is carried out, and the system enters a -sleep state (or a system image is created). During resume (or after the image -has been created or loaded) a sysdev_driver.resume phase is carried out, IRQs -are enabled on the only online CPU, the non-boot CPUs are enabled, and the -resume_noirq (or thaw_noirq or restore_noirq) phase begins. - -Code to actually enter and exit the system-wide low power state sometimes -involves hardware details that are only known to the boot firmware, and -may leave a CPU running software (from SRAM or flash memory) that monitors -the system and manages its wakeup sequence. - - Device Low Power (suspend) States --------------------------------- Device low-power states aren't standard. One device might only handle |