bus_find_device — device iterator for locating a particular device.
| struct device * bus_find_device ( | struct bus_type * bus, | 
| struct device * start, | |
| void * data, | |
| int (*match) (struct device *dev, void *data)); | 
busbus type
startDevice to begin with
dataData to pass to match function
matchCallback function to check device
   This is similar to the bus_for_each_dev function above, but it
   returns a reference to a device that is 'found' for later use, as
   determined by the match callback.
   
The callback should return 0 if the device doesn't match and non-zero if it does. If the callback returns non-zero, this function will return to the caller and not iterate over any more devices.