1 To understand all the Linux-USB framework, you'll use these resources:
3 * This source code. This is necessarily an evolving work, and
4 includes kerneldoc that should help you get a current overview.
5 ("make pdfdocs", and then look at "usb.pdf" for host side and
6 "gadget.pdf" for peripheral side.) Also, Documentation/usb has
7 more information.
9 * The USB 2.0 specification (from www.usb.org), with supplements
10 such as those for USB OTG and the various device classes.
11 The USB specification has a good overview chapter, and USB
12 peripherals conform to the widely known "Chapter 9".
14 * Chip specifications for USB controllers. Examples include
15 host controllers (on PCs, servers, and more); peripheral
16 controllers (in devices with Linux firmware, like printers or
17 cell phones); and hard-wired peripherals like Ethernet adapters.
19 * Specifications for other protocols implemented by USB peripheral
20 functions. Some are vendor-specific; others are vendor-neutral
21 but just standardized outside of the www.usb.org team.
23 Here is a list of what each subdirectory here is, and what is contained in
26 core/ - This is for the core USB host code, including the
27 usbfs files and the hub class driver ("hub_wq").
29 host/ - This is for USB host controller drivers. This
30 includes UHCI, OHCI, EHCI, and others that might
31 be used with more specialized "embedded" systems.
33 gadget/ - This is for USB peripheral controller drivers and
34 the various gadget drivers which talk to them.
37 Individual USB driver directories. A new driver should be added to the
38 first subdirectory in the list below that it fits into.
40 image/ - This is for still image drivers, like scanners or
41 digital cameras.
42 ../input/ - This is for any driver that uses the input subsystem,
43 like keyboard, mice, touchscreens, tablets, etc.
44 ../media/ - This is for multimedia drivers, like video cameras,
45 radios, and any other drivers that talk to the v4l
47 ../net/ - This is for network drivers.
48 serial/ - This is for USB to serial drivers.
49 storage/ - This is for USB mass-storage drivers.
50 class/ - This is for all USB device drivers that do not fit
51 into any of the above categories, and work for a range
52 of USB Class specified devices.
53 misc/ - This is for all USB device drivers that do not fit
54 into any of the above categories.