driver_for_each_device - Iterator for devices bound to a driver.
int driver_for_each_device (struct device_driver * drv, struct device * start, void * data, int (*fn) <funcparams>struct device *, void *</funcparams>);
drv Driver we’re iterating. start Device to begin with data Data to pass to the callback. fn Function to call for each device.
Iterate over the drv’s list of devices calling fn for each one.