OpenCloudOS-Kernel/include/linux/usb/functionfs.h

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USB: f_fs: the FunctionFS driver The FunctionFS is a USB composite function that can be used with the composite framework to create an USB gadget. >From kernel point of view it is just a composite function with some unique behaviour. It may be added to an USB configuration only after the user space driver has registered by writing descriptors and strings (the user space program has to provide the same information that kernel level composite functions provide when they are added to the configuration). >From user space point of view it is a file system which when mounted provide an "ep0" file. User space driver need to write descriptors and strings to that file. It does not need to worry about endpoints, interfaces or strings numbers but simply provide descriptors such as if the function was the only one (endpoints and strings numbers starting from one and interface numbers starting from core). The FunctionFS changes numbers of those as needed also handling situation when numbers differ in different configurations. When descriptors and strings are written "ep#" files appear (one for each declared endpoint) which handle communication on a single endpoint. Again, FunctionFS takes care of the real numbers and changing of the configuration (which means that "ep1" file may be really mapped to (say) endpoint 3 (and when configuration changes to (say) endpoint 2)). "ep0" is used for receiving events and handling setup requests. When all files are closed the function disables itself. Signed-off-by: Michal Nazarewicz <m.nazarewicz@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-05 18:53:14 +08:00
#ifndef __LINUX_FUNCTIONFS_H__
#define __LINUX_FUNCTIONFS_H__ 1
#include <uapi/linux/usb/functionfs.h>
USB: f_fs: the FunctionFS driver The FunctionFS is a USB composite function that can be used with the composite framework to create an USB gadget. >From kernel point of view it is just a composite function with some unique behaviour. It may be added to an USB configuration only after the user space driver has registered by writing descriptors and strings (the user space program has to provide the same information that kernel level composite functions provide when they are added to the configuration). >From user space point of view it is a file system which when mounted provide an "ep0" file. User space driver need to write descriptors and strings to that file. It does not need to worry about endpoints, interfaces or strings numbers but simply provide descriptors such as if the function was the only one (endpoints and strings numbers starting from one and interface numbers starting from core). The FunctionFS changes numbers of those as needed also handling situation when numbers differ in different configurations. When descriptors and strings are written "ep#" files appear (one for each declared endpoint) which handle communication on a single endpoint. Again, FunctionFS takes care of the real numbers and changing of the configuration (which means that "ep1" file may be really mapped to (say) endpoint 3 (and when configuration changes to (say) endpoint 2)). "ep0" is used for receiving events and handling setup requests. When all files are closed the function disables itself. Signed-off-by: Michal Nazarewicz <m.nazarewicz@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-05 18:53:14 +08:00
struct ffs_data;
struct usb_composite_dev;
struct usb_configuration;
static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
__attribute__((warn_unused_result, nonnull));
static void functionfs_unbind(struct ffs_data *ffs)
__attribute__((nonnull));
static int functionfs_bind_config(struct usb_composite_dev *cdev,
struct usb_configuration *c,
struct ffs_data *ffs)
USB: f_fs: the FunctionFS driver The FunctionFS is a USB composite function that can be used with the composite framework to create an USB gadget. >From kernel point of view it is just a composite function with some unique behaviour. It may be added to an USB configuration only after the user space driver has registered by writing descriptors and strings (the user space program has to provide the same information that kernel level composite functions provide when they are added to the configuration). >From user space point of view it is a file system which when mounted provide an "ep0" file. User space driver need to write descriptors and strings to that file. It does not need to worry about endpoints, interfaces or strings numbers but simply provide descriptors such as if the function was the only one (endpoints and strings numbers starting from one and interface numbers starting from core). The FunctionFS changes numbers of those as needed also handling situation when numbers differ in different configurations. When descriptors and strings are written "ep#" files appear (one for each declared endpoint) which handle communication on a single endpoint. Again, FunctionFS takes care of the real numbers and changing of the configuration (which means that "ep1" file may be really mapped to (say) endpoint 3 (and when configuration changes to (say) endpoint 2)). "ep0" is used for receiving events and handling setup requests. When all files are closed the function disables itself. Signed-off-by: Michal Nazarewicz <m.nazarewicz@samsung.com> Cc: Kyungmin Park <kyungmin.park@samsung.com> Cc: Marek Szyprowski <m.szyprowski@samsung.com> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-05-05 18:53:14 +08:00
__attribute__((warn_unused_result, nonnull));
#endif