In This Chapter
Bootstrap Essentials: Linux USB Hub
Linux USB Hub Framework
The universal serial bus (USB) standard supports up to 127 physical device connections by a host. But a typical host computer supports a limited number of ports and thus can connect only a few devices. The USB specification defines a device model referred to as a hub device that allows a host to extend its port and connect multiple devices. A USB host controller is integrated with a root hub to provide one or more attachment points. Figure 8.1 illustrates a typical host, root hub, hub, and device relationship.
Figure 8.1. A USB host, hub, and device relationship ...