pci_get_class — begin or continue searching for a PCI device by class
| struct pci_dev * pci_get_class ( | unsigned int class, | 
| struct pci_dev * from ); | 
classsearch for a PCI device with this class designation
from
     Previous PCI device found in search, or NULL for new search.
    
   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.