Linux Device Drivers Development

Bus registration

The bus controller is a device itself, and in 99% of cases buses are platform devices (even buses that offer enumeration). For example, the PCI controller is a platform device, and so is its respective driver. One must use the bus_register(struct *bus_type) function in order to register a bus with the kernel. The packt bus structure looks like this:

/* 
 * This is our bus structure 
 */ 
struct bus_type packt_bus_type = { 
   .name      = "packt", 
   .match     = packt_device_match, 
   .probe     = packt_device_probe, 
   .remove    = packt_device_remove, 
   .shutdown  = packt_device_shutdown, 
}; 

The bus controller is a device itself; it has to be registered with the kernel, and will be used as a parent of the device siting on the bus. This is done in the bus ...