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| author |   Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2016-10-30 17:32:31 +0100 |
|---|---|---|
| committer |   Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-10-31 11:42:51 -0600 |
| commit | 21d5c57b3726166421251e94dabab047baaf8ce4 (patch) | |
| tree | 11534c3ef07222913f2527c9c8ff41478d259777 /include/linux/pm_runtime.h | |
| parent | PM / sleep: Make async suspend/resume of devices use device links (diff) | |
| download | linux-dev-21d5c57b3726166421251e94dabab047baaf8ce4.tar.xz linux-dev-21d5c57b3726166421251e94dabab047baaf8ce4.zip | |
PM / runtime: Use device links
Modify the runtime PM framework to use device links to ensure that
supplier devices will not be suspended if any of their consumer
devices are active.
The idea is to reference count suppliers on the consumer's resume
and drop references to them on its suspend. The information on
whether or not the supplier has been reference counted by the
consumer's (runtime) resume is stored in a new field (rpm_active)
in the link object for each link.
It may be necessary to clean up those references when the
supplier is unbinding and that's why the links whose status is
DEVICE_LINK_SUPPLIER_UNBIND are skipped by the runtime suspend
and resume code.
The above means that if the consumer device is probed in the
runtime-active state, the supplier has to be resumed and reference
counted by device_link_add() so the code works as expected on its
(runtime) suspend. There is a new flag, DEVICE_LINK_RPM_ACTIVE,
to tell device_link_add() about that (in which case the caller
is responsible for making sure that the consumer really will
be runtime-active when runtime PM is enabled for it).
The other new link flag, DEVICE_LINK_PM_RUNTIME, tells the core
whether or not the link should be used for runtime PM at all.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/pm_runtime.h')
| -rw-r--r-- | include/linux/pm_runtime.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/pm_runtime.h b/include/linux/pm_runtime.h index 2e14d2667b6c..c2ee87138e4a 100644 --- a/include/linux/pm_runtime.h +++ b/include/linux/pm_runtime.h @@ -55,6 +55,9 @@ extern unsigned long pm_runtime_autosuspend_expiration(struct device *dev); extern void pm_runtime_update_max_time_suspended(struct device *dev, s64 delta_ns); extern void pm_runtime_set_memalloc_noio(struct device *dev, bool enable); +extern void pm_runtime_clean_up_links(struct device *dev); +extern void pm_runtime_get_suppliers(struct device *dev); +extern void pm_runtime_put_suppliers(struct device *dev); static inline void pm_suspend_ignore_children(struct device *dev, bool enable) { @@ -186,6 +189,9 @@ static inline unsigned long pm_runtime_autosuspend_expiration( struct device *dev) { return 0; } static inline void pm_runtime_set_memalloc_noio(struct device *dev, bool enable){} +static inline void pm_runtime_clean_up_links(struct device *dev) {} +static inline void pm_runtime_get_suppliers(struct device *dev) {} +static inline void pm_runtime_put_suppliers(struct device *dev) {} #endif /* !CONFIG_PM */ |