diff options
Diffstat (limited to 'Documentation/power')
| -rw-r--r-- | Documentation/power/devices.txt | 7 | ||||
| -rw-r--r-- | Documentation/power/runtime_pm.txt | 4 | ||||
| -rw-r--r-- | Documentation/power/suspend-and-cpuhotplug.txt | 6 |
3 files changed, 10 insertions, 7 deletions
diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt index d172bce0fd49..8ba6625fdd63 100644 --- a/Documentation/power/devices.txt +++ b/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, diff --git a/Documentation/power/runtime_pm.txt b/Documentation/power/runtime_pm.txt index e76dc0ad4d2b..0784bc3a2ab5 100644 --- a/Documentation/power/runtime_pm.txt +++ b/Documentation/power/runtime_pm.txt @@ -445,10 +445,6 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h: bool pm_runtime_status_suspended(struct device *dev); - return true if the device's runtime PM status is 'suspended' - bool pm_runtime_suspended_if_enabled(struct device *dev); - - return true if the device's runtime PM status is 'suspended' and its - 'power.disable_depth' field is equal to 1 - void pm_runtime_allow(struct device *dev); - set the power.runtime_auto flag for the device and decrease its usage counter (used by the /sys/devices/.../power/control interface to diff --git a/Documentation/power/suspend-and-cpuhotplug.txt b/Documentation/power/suspend-and-cpuhotplug.txt index 2850df3bf957..2fc909502db5 100644 --- a/Documentation/power/suspend-and-cpuhotplug.txt +++ b/Documentation/power/suspend-and-cpuhotplug.txt @@ -72,7 +72,7 @@ More details follow: | v Disable regular cpu hotplug - by setting cpu_hotplug_disabled=1 + by increasing cpu_hotplug_disabled | v Release cpu_add_remove_lock @@ -89,7 +89,7 @@ Resuming back is likewise, with the counterparts being (in the order of execution during resume): * enable_nonboot_cpus() which involves: | Acquire cpu_add_remove_lock - | Reset cpu_hotplug_disabled to 0, thereby enabling regular cpu hotplug + | Decrease cpu_hotplug_disabled, thereby enabling regular cpu hotplug | Call _cpu_up() [for all those cpus in the frozen_cpus mask, in a loop] | Release cpu_add_remove_lock v @@ -120,7 +120,7 @@ after the entire cycle is complete (i.e., suspend + resume). Acquire cpu_add_remove_lock | v - If cpu_hotplug_disabled is 1 + If cpu_hotplug_disabled > 0 return gracefully | | |