centos man page for pci_set_power_state

PCI_SET_POWER_STATE(9)						Hardware Interfaces					    PCI_SET_POWER_STATE(9)

NAME
       pci_set_power_state - Set the power state of a PCI device

SYNOPSIS
       int pci_set_power_state(struct pci_dev * dev, pci_power_t state);

ARGUMENTS
       dev
	   PCI device to handle.

       state
	   PCI power state (D0, D1, D2, D3hot) to put the device into.

DESCRIPTION
       Transition a device to a new power state, using the platform firmware and/or the device's PCI PM registers.

RETURN VALUE
       -EINVAL if the requested state is invalid. -EIO if device does not support PCI PM or its PM capabilities register has a wrong version, or
       device doesn't support the requested state. 0 if device already is in the requested state. 0 if device's power state has been successfully
       changed.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014						    PCI_SET_POWER_STATE(9)