Lines Matching full:runtime
2 Runtime Power Management Framework for I/O Devices
14 Support for runtime power management (runtime PM) of I/O devices is provided
19 used for queuing all work items related to runtime PM, because this allows
24 * A number of runtime PM fields in the 'power' member of 'struct device' (which
26 be used for synchronizing runtime PM operations with one another.
28 * Three device runtime PM callbacks in 'struct dev_pm_ops' (defined in
31 * A set of helper functions defined in drivers/base/power/runtime.c that can be
32 used for carrying out runtime PM operations in such a way that the
36 The runtime PM callbacks present in 'struct dev_pm_ops', the device runtime PM
38 runtime PM are described below.
40 2. Device Runtime PM Callbacks
43 There are three device runtime PM callbacks defined in 'struct dev_pm_ops'::
98 RAM until the appropriate resume callback is executed for it. The runtime
102 * If the suspend callback returns -EBUSY or -EAGAIN, the device's runtime PM
131 I/O operations as needed. The runtime PM status of the device is then
155 0, then the PM core will attempt to carry out a runtime suspend of the device,
164 that the following constraints are met with respect to runtime PM callbacks for
176 ->runtime_suspend() for the devices the runtime PM status of which is
185 PM core will only execute ->runtime_resume() for the devices the runtime
205 3. Runtime PM Device Fields
208 The following device runtime PM fields are present in 'struct dev_pm_info', as
240 equal to zero); the initial value of it is 1 (i.e. runtime PM is
264 - the runtime PM status of the device; this field's initial value is
275 - indicates that the device does not use the runtime PM callbacks (see
302 4. Runtime PM Device Helper Functions
305 The following runtime PM helper functions are defined in
306 drivers/base/power/runtime.c and include/linux/pm_runtime.h:
309 - initialize the device runtime PM fields in 'struct dev_pm_info'
312 - make sure that the runtime PM of the device will be disabled after
323 success, 1 if the device's runtime PM status was already 'suspended', or
336 success, 1 if the device's runtime PM status was already 'active' or
361 runtime status was already 'suspended', or error code if the request
369 success, 1 if the device's runtime PM status was already 'active', or
389 runtime PM status is RPM_ACTIVE and the runtime PM usage counter is
395 runtime PM status is RPM_ACTIVE, and either ign_usage_count is true
424 to zero, the runtime PM helper functions can execute subsystem-level
429 field was previously zero, this prevents subsystem-level runtime PM
431 pending runtime PM operations on the device are either completed or
438 (synchronously) in that case, cancel any other pending runtime PM requests
439 regarding it and wait for all runtime PM operations on it in progress to
448 - clear the device's 'power.runtime_error' flag, set the device's runtime
456 - clear the device's 'power.runtime_error' flag, set the device's runtime
463 - return true if the device's runtime PM status is 'active' or its
467 - return true if the device's runtime PM status is 'suspended' and its
471 - return true if the device's runtime PM status is 'suspended'
484 - set the power.no_callbacks flag for the device and remove the runtime
489 - set the power.irq_safe flag for the device, causing the runtime-PM
494 the runtime-PM callbacks to be invoked with interrupts off
511 milliseconds); if 'delay' is negative then runtime suspends are
557 5. Runtime PM Initialization, Device Probing and Removal
560 Initially, the runtime PM is disabled for all devices, which means that the
561 majority of the runtime PM helper functions described in Section 4 will return
564 In addition to that, the initial runtime PM status of all devices is
567 runtime PM status must be changed to 'active', with the help of
570 However, if the device has a parent and the parent's runtime PM is enabled,
575 runtime PM is still disabled (i.e. pm_runtime_enable() hasn't been called for
578 should be called for it too as soon as reasonably possible or its runtime PM
582 If the default initial runtime PM status of the device (i.e. 'suspended')
586 should be used. Of course, for this purpose the device's runtime PM has to be
598 time. A driver that makes use of the runtime autosuspend feature may want to
601 Moreover, the driver core prevents runtime PM callbacks from racing with the bus
604 runtime PM functionality. It does so by calling pm_runtime_get_sync() before
613 drivers to make their ->remove() callbacks avoid races with runtime PM directly,
617 Drivers in ->remove() callback should undo the runtime PM changes done
625 runtime power management of the device until the user space turns it on.
626 Namely, during the initialization the driver can make sure that the runtime PM
633 6. Runtime PM and System Sleep
636 Runtime PM and system sleep (i.e., system suspend and hibernation, also known
641 The device may have different wake-up settings for runtime PM and system sleep.
642 For example, remote wake-up may be enabled for runtime suspend but disallowed
648 or other settings for runtime suspend and system sleep.
667 likely it would need a runtime resume in the near future anyway.
670 brought back to full power during resume, then its runtime PM status will have
678 The PM core always increments the runtime usage counter before calling the
680 Hence disabling runtime PM temporarily like this will not cause any runtime
700 that the device appears to be runtime-suspended and its state is fine, so it
701 may be left in runtime suspend provided that all of its descendants are also
702 left in runtime suspend. If that happens, the PM core will not execute any
710 the runtime PM and system suspend/resume (and hibernation) callbacks by carrying
752 if successful, change the device's runtime PM status to 'active'
789 if successful, change the device's runtime PM status to 'active'
802 poweroff and runtime suspend callback, and similarly for system resume, thaw,
803 restore, and runtime resume, can achieve this with the help of the
814 need of runtime PM callbacks; if the callbacks did exist, ->runtime_suspend()
822 prevent the non-debugging runtime PM sysfs attributes from being created.
830 or driver about runtime power changes. Instead, the driver for the device's
836 the runtime PM callbacks needs to be implemented, a platform dependent PM
839 in subsystems/drivers, the PM core allows runtime PM callbacks to be
851 at runtime until they have been inactive for some minimum period. Even when
857 the appropriate PM routines); rather it means that runtime suspends will