Documentation: fix driver-api doc refs

This document only covers the aspects of power management specific to PCI

This document only covers the aspects of power management specific to PCI

devices.  For general description of the kernel's interfaces related to device

devices.  For general description of the kernel's interfaces related to device

power management refer to Documentation/power/admin-guide/devices.rst and

power management refer to Documentation/driver-api/pm/devices.rst and

Documentation/power/runtime_pm.txt.

Documentation/power/runtime_pm.txt.

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2.4. System-Wide Power Transitions

2.4. System-Wide Power Transitions

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There are a few different types of system-wide power transitions, described in

There are a few different types of system-wide power transitions, described in

Documentation/power/admin-guide/devices.rst.  Each of them requires devices to be handled

Documentation/driver-api/pm/devices.rst.  Each of them requires devices to be handled

in a specific way and the PM core executes subsystem-level power management

in a specific way and the PM core executes subsystem-level power management

callbacks for this purpose.  They are executed in phases such that each phase

callbacks for this purpose.  They are executed in phases such that each phase

involves executing the same subsystem-level callback for every device belonging

involves executing the same subsystem-level callback for every device belonging

pre-hibernation memory contents to be restored before the pre-hibernation system

pre-hibernation memory contents to be restored before the pre-hibernation system

activity can be resumed.

activity can be resumed.

As described in Documentation/power/admin-guide/devices.rst, the hibernation image is loaded

As described in Documentation/driver-api/pm/devices.rst, the hibernation image is loaded

into memory by a fresh instance of the kernel, called the boot kernel, which in

into memory by a fresh instance of the kernel, called the boot kernel, which in

turn is loaded and run by a boot loader in the usual way.  After the boot kernel

turn is loaded and run by a boot loader in the usual way.  After the boot kernel

has loaded the image, it needs to replace its own code and data with the code

has loaded the image, it needs to replace its own code and data with the code

At the time of this writing there are two ways to define power management

At the time of this writing there are two ways to define power management

callbacks for a PCI device driver, the recommended one, based on using a

callbacks for a PCI device driver, the recommended one, based on using a

dev_pm_ops structure described in Documentation/power/admin-guide/devices.rst, and the

dev_pm_ops structure described in Documentation/driver-api/pm/devices.rst, and the

"legacy" one, in which the .suspend(), .suspend_late(), .resume_early(), and

"legacy" one, in which the .suspend(), .suspend_late(), .resume_early(), and

.resume() callbacks from struct pci_driver are used.  The legacy approach,

.resume() callbacks from struct pci_driver are used.  The legacy approach,

however, doesn't allow one to define runtime power management callbacks and is

however, doesn't allow one to define runtime power management callbacks and is

PCI Bus Power Management Interface Specification, Rev. 1.2

PCI Bus Power Management Interface Specification, Rev. 1.2

Advanced Configuration and Power Interface (ACPI) Specification, Rev. 3.0b

Advanced Configuration and Power Interface (ACPI) Specification, Rev. 3.0b

PCI Express Base Specification, Rev. 2.0

PCI Express Base Specification, Rev. 2.0

Documentation/power/admin-guide/devices.rst

Documentation/driver-api/pm/devices.rst

Documentation/power/runtime_pm.txt

Documentation/power/runtime_pm.txt

system suspend and resume callbacks for all of those devices, except for the

system suspend and resume callbacks for all of those devices, except for the

complete callback, which is then entirely responsible for handling the device

complete callback, which is then entirely responsible for handling the device

as appropriate.  This only applies to system suspend transitions that are not

as appropriate.  This only applies to system suspend transitions that are not

related to hibernation (see Documentation/power/admin-guide/devices.rst for more

related to hibernation (see Documentation/driver-api/pm/devices.rst for more

information).

information).

The PM core does its best to reduce the probability of race conditions between

The PM core does its best to reduce the probability of race conditions between

		anything.  For the driver testing instructions see

		anything.  For the driver testing instructions see

		Documentation/power/drivers-testing.txt and for a relatively

		Documentation/power/drivers-testing.txt and for a relatively

		complete overview of the power management issues related to

		complete overview of the power management issues related to

		drivers see Documentation/power/admin-guide/devices.rst .

		drivers see Documentation/driver-api/pm/devices.rst.

Control:

Control:

		In general if there is active maintenance of a driver by

		In general if there is active maintenance of a driver by