This file is indexed.

/usr/arm-linux-gnueabihf/include/linux/usb/functionfs.h is in linux-libc-dev-armhf-cross 4.15.0-18.19cross1.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
#ifndef __LINUX_FUNCTIONFS_H__
#define __LINUX_FUNCTIONFS_H__


#include <linux/types.h>
#include <linux/ioctl.h>

#include <linux/usb/ch9.h>


enum {
	FUNCTIONFS_DESCRIPTORS_MAGIC = 1,
	FUNCTIONFS_STRINGS_MAGIC = 2,
	FUNCTIONFS_DESCRIPTORS_MAGIC_V2 = 3,
};

enum functionfs_flags {
	FUNCTIONFS_HAS_FS_DESC = 1,
	FUNCTIONFS_HAS_HS_DESC = 2,
	FUNCTIONFS_HAS_SS_DESC = 4,
	FUNCTIONFS_HAS_MS_OS_DESC = 8,
	FUNCTIONFS_VIRTUAL_ADDR = 16,
	FUNCTIONFS_EVENTFD = 32,
	FUNCTIONFS_ALL_CTRL_RECIP = 64,
	FUNCTIONFS_CONFIG0_SETUP = 128,
};

/* Descriptor of an non-audio endpoint */
struct usb_endpoint_descriptor_no_audio {
	__u8  bLength;
	__u8  bDescriptorType;

	__u8  bEndpointAddress;
	__u8  bmAttributes;
	__le16 wMaxPacketSize;
	__u8  bInterval;
} __attribute__((packed));

struct usb_functionfs_descs_head_v2 {
	__le32 magic;
	__le32 length;
	__le32 flags;
	/*
	 * __le32 fs_count, hs_count, fs_count; must be included manually in
	 * the structure taking flags into consideration.
	 */
} __attribute__((packed));

/* Legacy format, deprecated as of 3.14. */
struct usb_functionfs_descs_head {
	__le32 magic;
	__le32 length;
	__le32 fs_count;
	__le32 hs_count;
} __attribute__((packed, deprecated));

/* MS OS Descriptor header */
struct usb_os_desc_header {
	__u8	interface;
	__le32	dwLength;
	__le16	bcdVersion;
	__le16	wIndex;
	union {
		struct {
			__u8	bCount;
			__u8	Reserved;
		};
		__le16	wCount;
	};
} __attribute__((packed));

struct usb_ext_compat_desc {
	__u8	bFirstInterfaceNumber;
	__u8	Reserved1;
	__u8	CompatibleID[8];
	__u8	SubCompatibleID[8];
	__u8	Reserved2[6];
};

struct usb_ext_prop_desc {
	__le32	dwSize;
	__le32	dwPropertyDataType;
	__le16	wPropertyNameLength;
} __attribute__((packed));


/*
 * Descriptors format:
 *
 * | off | name      | type         | description                          |
 * |-----+-----------+--------------+--------------------------------------|
 * |   0 | magic     | LE32         | FUNCTIONFS_DESCRIPTORS_MAGIC_V2      |
 * |   4 | length    | LE32         | length of the whole data chunk       |
 * |   8 | flags     | LE32         | combination of functionfs_flags      |
 * |     | eventfd   | LE32         | eventfd file descriptor              |
 * |     | fs_count  | LE32         | number of full-speed descriptors     |
 * |     | hs_count  | LE32         | number of high-speed descriptors     |
 * |     | ss_count  | LE32         | number of super-speed descriptors    |
 * |     | os_count  | LE32         | number of MS OS descriptors          |
 * |     | fs_descrs | Descriptor[] | list of full-speed descriptors       |
 * |     | hs_descrs | Descriptor[] | list of high-speed descriptors       |
 * |     | ss_descrs | Descriptor[] | list of super-speed descriptors      |
 * |     | os_descrs | OSDesc[]     | list of MS OS descriptors            |
 *
 * Depending on which flags are set, various fields may be missing in the
 * structure.  Any flags that are not recognised cause the whole block to be
 * rejected with -ENOSYS.
 *
 * Legacy descriptors format (deprecated as of 3.14):
 *
 * | off | name      | type         | description                          |
 * |-----+-----------+--------------+--------------------------------------|
 * |   0 | magic     | LE32         | FUNCTIONFS_DESCRIPTORS_MAGIC         |
 * |   4 | length    | LE32         | length of the whole data chunk       |
 * |   8 | fs_count  | LE32         | number of full-speed descriptors     |
 * |  12 | hs_count  | LE32         | number of high-speed descriptors     |
 * |  16 | fs_descrs | Descriptor[] | list of full-speed descriptors       |
 * |     | hs_descrs | Descriptor[] | list of high-speed descriptors       |
 *
 * All numbers must be in little endian order.
 *
 * Descriptor[] is an array of valid USB descriptors which have the following
 * format:
 *
 * | off | name            | type | description              |
 * |-----+-----------------+------+--------------------------|
 * |   0 | bLength         | U8   | length of the descriptor |
 * |   1 | bDescriptorType | U8   | descriptor type          |
 * |   2 | payload         |      | descriptor's payload     |
 *
 * OSDesc[] is an array of valid MS OS Feature Descriptors which have one of
 * the following formats:
 *
 * | off | name            | type | description              |
 * |-----+-----------------+------+--------------------------|
 * |   0 | inteface        | U8   | related interface number |
 * |   1 | dwLength        | U32  | length of the descriptor |
 * |   5 | bcdVersion      | U16  | currently supported: 1   |
 * |   7 | wIndex          | U16  | currently supported: 4   |
 * |   9 | bCount          | U8   | number of ext. compat.   |
 * |  10 | Reserved        | U8   | 0                        |
 * |  11 | ExtCompat[]     |      | list of ext. compat. d.  |
 *
 * | off | name            | type | description              |
 * |-----+-----------------+------+--------------------------|
 * |   0 | inteface        | U8   | related interface number |
 * |   1 | dwLength        | U32  | length of the descriptor |
 * |   5 | bcdVersion      | U16  | currently supported: 1   |
 * |   7 | wIndex          | U16  | currently supported: 5   |
 * |   9 | wCount          | U16  | number of ext. compat.   |
 * |  11 | ExtProp[]       |      | list of ext. prop. d.    |
 *
 * ExtCompat[] is an array of valid Extended Compatiblity descriptors
 * which have the following format:
 *
 * | off | name                  | type | description                         |
 * |-----+-----------------------+------+-------------------------------------|
 * |   0 | bFirstInterfaceNumber | U8   | index of the interface or of the 1st|
 * |     |                       |      | interface in an IAD group           |
 * |   1 | Reserved              | U8   | 1                                   |
 * |   2 | CompatibleID          | U8[8]| compatible ID string                |
 * |  10 | SubCompatibleID       | U8[8]| subcompatible ID string             |
 * |  18 | Reserved              | U8[6]| 0                                   |
 *
 * ExtProp[] is an array of valid Extended Properties descriptors
 * which have the following format:
 *
 * | off | name                  | type | description                         |
 * |-----+-----------------------+------+-------------------------------------|
 * |   0 | dwSize                | U32  | length of the descriptor            |
 * |   4 | dwPropertyDataType    | U32  | 1..7                                |
 * |   8 | wPropertyNameLength   | U16  | bPropertyName length (NL)           |
 * |  10 | bPropertyName         |U8[NL]| name of this property               |
 * |10+NL| dwPropertyDataLength  | U32  | bPropertyData length (DL)           |
 * |14+NL| bProperty             |U8[DL]| payload of this property            |
 */

struct usb_functionfs_strings_head {
	__le32 magic;
	__le32 length;
	__le32 str_count;
	__le32 lang_count;
} __attribute__((packed));

/*
 * Strings format:
 *
 * | off | name       | type                  | description                |
 * |-----+------------+-----------------------+----------------------------|
 * |   0 | magic      | LE32                  | FUNCTIONFS_STRINGS_MAGIC   |
 * |   4 | length     | LE32                  | length of the data chunk   |
 * |   8 | str_count  | LE32                  | number of strings          |
 * |  12 | lang_count | LE32                  | number of languages        |
 * |  16 | stringtab  | StringTab[lang_count] | table of strings per lang  |
 *
 * For each language there is one stringtab entry (ie. there are lang_count
 * stringtab entires).  Each StringTab has following format:
 *
 * | off | name    | type              | description                        |
 * |-----+---------+-------------------+------------------------------------|
 * |   0 | lang    | LE16              | language code                      |
 * |   2 | strings | String[str_count] | array of strings in given language |
 *
 * For each string there is one strings entry (ie. there are str_count
 * string entries).  Each String is a NUL terminated string encoded in
 * UTF-8.
 */



/*
 * Events are delivered on the ep0 file descriptor, when the user mode driver
 * reads from this file descriptor after writing the descriptors.  Don't
 * stop polling this descriptor.
 */

enum usb_functionfs_event_type {
	FUNCTIONFS_BIND,
	FUNCTIONFS_UNBIND,

	FUNCTIONFS_ENABLE,
	FUNCTIONFS_DISABLE,

	FUNCTIONFS_SETUP,

	FUNCTIONFS_SUSPEND,
	FUNCTIONFS_RESUME
};

/* NOTE:  this structure must stay the same size and layout on
 * both 32-bit and 64-bit kernels.
 */
struct usb_functionfs_event {
	union {
		/* SETUP: packet; DATA phase i/o precedes next event
		 *(setup.bmRequestType & USB_DIR_IN) flags direction */
		struct usb_ctrlrequest	setup;
	} __attribute__((packed)) u;

	/* enum usb_functionfs_event_type */
	__u8				type;
	__u8				_pad[3];
} __attribute__((packed));


/* Endpoint ioctls */
/* The same as in gadgetfs */

/* IN transfers may be reported to the gadget driver as complete
 *	when the fifo is loaded, before the host reads the data;
 * OUT transfers may be reported to the host's "client" driver as
 *	complete when they're sitting in the FIFO unread.
 * THIS returns how many bytes are "unclaimed" in the endpoint fifo
 * (needed for precise fault handling, when the hardware allows it)
 */
#define	FUNCTIONFS_FIFO_STATUS	_IO('g', 1)

/* discards any unclaimed data in the fifo. */
#define	FUNCTIONFS_FIFO_FLUSH	_IO('g', 2)

/* resets endpoint halt+toggle; used to implement set_interface.
 * some hardware (like pxa2xx) can't support this.
 */
#define	FUNCTIONFS_CLEAR_HALT	_IO('g', 3)

/* Specific for functionfs */

/*
 * Returns reverse mapping of an interface.  Called on EP0.  If there
 * is no such interface returns -EDOM.  If function is not active
 * returns -ENODEV.
 */
#define	FUNCTIONFS_INTERFACE_REVMAP	_IO('g', 128)

/*
 * Returns real bEndpointAddress of an endpoint. If endpoint shuts down
 * during the call, returns -ESHUTDOWN.
 */
#define	FUNCTIONFS_ENDPOINT_REVMAP	_IO('g', 129)

/*
 * Returns endpoint descriptor. If endpoint shuts down during the call,
 * returns -ESHUTDOWN.
 */
#define	FUNCTIONFS_ENDPOINT_DESC	_IOR('g', 130, \
					     struct usb_endpoint_descriptor)



#endif /* __LINUX_FUNCTIONFS_H__ */