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by Sebastien JAN
Initial Texas Instruments OMAP4 kernel for 2.6.34 |
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To understand all the Linux-USB framework, you'll use these resources: |
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* This source code. This is necessarily an evolving work, and |
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includes kerneldoc that should help you get a current overview. |
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("make pdfdocs", and then look at "usb.pdf" for host side and |
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"gadget.pdf" for peripheral side.) Also, Documentation/usb has |
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more information. |
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* The USB 2.0 specification (from www.usb.org), with supplements |
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such as those for USB OTG and the various device classes. |
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The USB specification has a good overview chapter, and USB |
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peripherals conform to the widely known "Chapter 9". |
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* Chip specifications for USB controllers. Examples include |
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host controllers (on PCs, servers, and more); peripheral |
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controllers (in devices with Linux firmware, like printers or |
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cell phones); and hard-wired peripherals like Ethernet adapters. |
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* Specifications for other protocols implemented by USB peripheral |
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functions. Some are vendor-specific; others are vendor-neutral |
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but just standardized outside of the www.usb.org team. |
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Here is a list of what each subdirectory here is, and what is contained in |
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them. |
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core/ - This is for the core USB host code, including the |
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usbfs files and the hub class driver ("khubd"). |
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host/ - This is for USB host controller drivers. This |
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includes UHCI, OHCI, EHCI, and others that might |
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be used with more specialized "embedded" systems. |
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gadget/ - This is for USB peripheral controller drivers and |
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the various gadget drivers which talk to them. |
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Individual USB driver directories. A new driver should be added to the |
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first subdirectory in the list below that it fits into. |
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image/ - This is for still image drivers, like scanners or |
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digital cameras. |
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../input/ - This is for any driver that uses the input subsystem, |
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like keyboard, mice, touchscreens, tablets, etc. |
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../media/ - This is for multimedia drivers, like video cameras, |
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radios, and any other drivers that talk to the v4l |
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subsystem. |
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../net/ - This is for network drivers. |
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serial/ - This is for USB to serial drivers. |
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storage/ - This is for USB mass-storage drivers. |
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class/ - This is for all USB device drivers that do not fit |
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into any of the above categories, and work for a range |
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of USB Class specified devices. |
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misc/ - This is for all USB device drivers that do not fit |
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into any of the above categories. |