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author | David Brownell <dbrownell@users.sourceforge.net> | 2008-06-20 00:52:58 (GMT) |
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committer | Greg Kroah-Hartman <gregkh@suse.de> | 2008-07-21 22:16:01 (GMT) |
commit | 40982be52d8f64c3e10adce17e66ab755a4fa26b (patch) | |
tree | 15abb3e3e99a5e8043648bf6b8b1214a75a43476 /Documentation/DocBook/gadget.tmpl | |
parent | a4c39c41bf3592684e36fa0dbbd4ab1a31f969b9 (diff) | |
download | linux-40982be52d8f64c3e10adce17e66ab755a4fa26b.tar.xz |
usb gadget: composite gadget core
Add <linux/usb/composite.h> interfaces for composite gadget drivers, and
basic implementation support behind it:
- struct usb_function ... groups one or more interfaces into a function
managed as one unit within a configuration, to which it's added by
usb_add_function().
- struct usb_configuration ... groups one or more such functions into
a configuration managed as one unit by a driver, to which it's added
by usb_add_config(). These operate at either high or full/low speeds
and at a given bMaxPower.
- struct usb_composite_driver ... groups one or more such configurations
into a gadget driver, which may be registered or unregistered.
- struct usb_composite_dev ... a usb_composite_driver manages this; it
wraps the usb_gadget exposed by the controller driver.
This also includes some basic kerneldoc.
How to use it (the short version): provide a usb_composite_driver with a
bind() that calls usb_add_config() for each of the needed configurations.
The configurations in turn have bind() calls, which will usb_add_function()
for each function required. Each function's bind() allocates resources
needed to perform its tasks, like endpoints; sometimes configurations will
allocate resources too.
Separate patches will convert most gadget drivers to this infrastructure.
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'Documentation/DocBook/gadget.tmpl')
-rw-r--r-- | Documentation/DocBook/gadget.tmpl | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/Documentation/DocBook/gadget.tmpl b/Documentation/DocBook/gadget.tmpl index 5a8ffa7..478bfe1 100644 --- a/Documentation/DocBook/gadget.tmpl +++ b/Documentation/DocBook/gadget.tmpl @@ -524,6 +524,41 @@ These utilities include endpoint autoconfiguration. <!-- !Edrivers/usb/gadget/epautoconf.c --> </sect1> +<sect1 id="composite"><title>Composite Device Framework</title> + +<para>The core API is sufficient for writing drivers for composite +USB devices (with more than one function in a given configuration), +and also multi-configuration devices (also more than one function, +but not necessarily sharing a given configuration). +There is however an optional framework which makes it easier to +reuse and combine functions. +</para> + +<para>Devices using this framework provide a <emphasis>struct +usb_composite_driver</emphasis>, which in turn provides one or +more <emphasis>struct usb_configuration</emphasis> instances. +Each such configuration includes at least one +<emphasis>struct usb_function</emphasis>, which packages a user +visible role such as "network link" or "mass storage device". +Management functions may also exist, such as "Device Firmware +Upgrade". +</para> + +!Iinclude/linux/usb/composite.h +!Edrivers/usb/gadget/composite.c + +</sect1> + +<sect1 id="functions"><title>Composite Device Functions</title> + +<para>At this writing, a few of the current gadget drivers have +been converted to this framework. +Near-term plans include converting all of them, except for "gadgetfs". +</para> + +</sect1> + + </chapter> <chapter id="controllers"><title>Peripheral Controller Drivers</title> |