LddDriverModelOverview < Training2

%SECTION0{name=LddDriverModelOverview}% How does it all fit together?

*Simplified example:*

   1. bus driver is loaded (Platform, USB, PCI...)
      * knows how to match devices and drivers
      * usually knows how to detect a device on the bus
      * maybe generates hotplug events for userspace
   1. bus driver detects devices:
      * statically by platform code
      * during bus driver initalization
      * when a device is hotplugged
   1. somewhere during startup some drivers get loaded
      * bus driver tries to match when new drivers or devices appear
   1. matching:
      * driver usually exports table of handled devices
      * matching is bus dependant, can not be implemented generically
      * no match && hotplugging enabled:
         * old: setup environment and call hotplug function (/proc/sys/kernel/hotplug)
         * today: udev/udevd handles this
         * try to autoload / modprobe correct module
         * if success retry matching
   1. if match:
      * call driver probe() function:
         * if < 0: failure
         * if >= 0: ok, driver is bound to device

5.5.1. Driver model and sysfs		1. Denx Training Topics		5.5.3. Driver model and flattened device tree
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