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| author | Lina Iyer <lina.iyer@linaro.org> | 2016-10-24 23:38:47 +0200 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2016-10-24 23:48:22 +0200 |
| commit | 411bf2a8db76d7ed6f710df77121e5113ee8fe64 (patch) | |
| tree | a31018fadf532930745d47525d867c5c5764fe15 /Documentation/power | |
| parent | PM / Domains: Support IRQ safe PM domains (diff) | |
| download | linux-411bf2a8db76d7ed6f710df77121e5113ee8fe64.tar.xz linux-411bf2a8db76d7ed6f710df77121e5113ee8fe64.zip | |
PM / doc: Update device documentation for devices in IRQ-safe PM domains
Update documentation to reflect the changes made to support IRQ safe PM
domains.
Suggested-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: Lina Iyer <lina.iyer@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'Documentation/power')
| -rw-r--r-- | Documentation/power/devices.txt | 14 |
1 files changed, 13 insertions, 1 deletions
diff --git a/Documentation/power/devices.txt b/Documentation/power/devices.txt index 8ba6625fdd63..73ddea39a9ce 100644 --- a/Documentation/power/devices.txt +++ b/Documentation/power/devices.txt @@ -607,7 +607,9 @@ individually. Instead, a set of devices sharing a power resource can be put into a low-power state together at the same time by turning off the shared power resource. Of course, they also need to be put into the full-power state together, by turning the shared power resource on. A set of devices with this -property is often referred to as a power domain. +property is often referred to as a power domain. A power domain may also be +nested inside another power domain. The nested domain is referred to as the +sub-domain of the parent domain. Support for power domains is provided through the pm_domain field of struct device. This field is a pointer to an object of type struct dev_pm_domain, @@ -629,6 +631,16 @@ support for power domains into subsystem-level callbacks, for example by modifying the platform bus type. Other platforms need not implement it or take it into account in any way. +Devices may be defined as IRQ-safe which indicates to the PM core that their +runtime PM callbacks may be invoked with disabled interrupts (see +Documentation/power/runtime_pm.txt for more information). If an IRQ-safe +device belongs to a PM domain, the runtime PM of the domain will be +disallowed, unless the domain itself is defined as IRQ-safe. However, it +makes sense to define a PM domain as IRQ-safe only if all the devices in it +are IRQ-safe. Moreover, if an IRQ-safe domain has a parent domain, the runtime +PM of the parent is only allowed if the parent itself is IRQ-safe too with the +additional restriction that all child domains of an IRQ-safe parent must also +be IRQ-safe. Device Low Power (suspend) States --------------------------------- |