1USB_INTERFACE_ID(9) Kernel Mode Gadget API USB_INTERFACE_ID(9)
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6 usb_interface_id - allocate an unused interface ID
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9 int usb_interface_id(struct usb_configuration * config,
10 struct usb_function * function);
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13 config
14 configuration associated with the interface
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16 function
17 function handling the interface
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20 single threaded during gadget setup
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23 usb_interface_id is called from usb_function.bind callbacks to allocate
24 new interface IDs. The function driver will then store that ID in
25 interface, association, CDC union, and other descriptors. It will also
26 handle any control requests targetted at that interface, particularly
27 changing its altsetting via set_alt. There may also be class-specific
28 or vendor-specific requests to handle.
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30 All interface identifier should be allocated using this routine, to
31 ensure that for example different functions don't wrongly assign
32 different meanings to the same identifier. Note that since interface
33 identifers are configuration-specific, functions used in more than one
34 configuration (or more than once in a given configuration) need
35 multiple versions of the relevant descriptors.
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37 Returns the interface ID which was allocated; or -ENODEV if no more
38 interface IDs can be allocated.
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41 David Brownell <dbrownell@users.sourceforge.net>
42 Author.
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45Kernel Hackers Manual 2.6. November 2011 USB_INTERFACE_ID(9)