centos man page for pci_get_class

PCI_GET_CLASS(9)						Hardware Interfaces						  PCI_GET_CLASS(9)

NAME
       pci_get_class - begin or continue searching for a PCI device by class

SYNOPSIS
       struct pci_dev * pci_get_class(unsigned int class, struct pci_dev * from);

ARGUMENTS
       class
	   search for a PCI device with this class designation

       from
	   Previous PCI device found in search, or NULL for new search.

DESCRIPTION
       Iterates through the list of known PCI devices. If a PCI device is found with a matching class, the reference count to the device is
       incremented and a pointer to its device structure is returned. Otherwise, NULL is returned. A new search is initiated by passing NULL as
       the from argument. Otherwise if from is not NULL, searches continue from next device on the global list. The reference count for from is
       always decremented if it is not NULL.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014							  PCI_GET_CLASS(9)