Chapter 3. Driver Initialisation

Table of Contents

3.1. Identifying an USB Device
3.2. Finding appropriate device driver
3.3. Module Device Drivers
3.3.1. Using the new device message
3.3.2. Module finalisation
3.4. Driver started by USB system
3.4.1. Format of the command string
3.5. Unclaimed Devices
3.5.1. Finding and using unclaimed devices
3.6. Returning devices after use

When a USB device is attached to a port, either on the host controller or on a hub the USB system performs several actions:

  1. Configures the USB address of the device.

  2. Reads the device configuration.

  3. Checks that power and bandwidth requirements do not exceed available resources.

  4. Creates the necessary USB resources for the devices reported configuration.

  5. Searches for an appropriate driver to handle the device.