aboutsummaryrefslogtreecommitdiff
path: root/drivers/usb/gadget/f_obex.c
blob: b4a3ba654ea53def501a4b7b6befdf83ba78bad1 (plain)
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
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
/*
 * f_obex.c -- USB CDC OBEX function driver
 *
 * Copyright (C) 2008 Nokia Corporation
 * Contact: Felipe Balbi <felipe.balbi@nokia.com>
 *
 * Based on f_acm.c by Al Borchers and David Brownell.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

/* #define VERBOSE_DEBUG */

#include <linux/kernel.h>
#include <linux/device.h>

#include "u_serial.h"
#include "gadget_chips.h"


/*
 * This CDC OBEX function support just packages a TTY-ish byte stream.
 * A user mode server will put it into "raw" mode and handle all the
 * relevant protocol details ... this is just a kernel passthrough.
 * When possible, we prevent gadget enumeration until that server is
 * ready to handle the commands.
 */

struct obex_ep_descs {
	struct usb_endpoint_descriptor	*obex_in;
	struct usb_endpoint_descriptor	*obex_out;
};

struct f_obex {
	struct gserial			port;
	u8				ctrl_id;
	u8				data_id;
	u8				port_num;
	u8				can_activate;

	struct obex_ep_descs		fs;
	struct obex_ep_descs		hs;
};

static inline struct f_obex *func_to_obex(struct usb_function *f)
{
	return container_of(f, struct f_obex, port.func);
}

static inline struct f_obex *port_to_obex(struct gserial *p)
{
	return container_of(p, struct f_obex, port);
}

/*-------------------------------------------------------------------------*/

#define OBEX_CTRL_IDX	0
#define OBEX_DATA_IDX	1

static struct usb_string obex_string_defs[] = {
	[OBEX_CTRL_IDX].s	= "CDC Object Exchange (OBEX)",
	[OBEX_DATA_IDX].s	= "CDC OBEX Data",
	{  },	/* end of list */
};

static struct usb_gadget_strings obex_string_table = {
	.language		= 0x0409,	/* en-US */
	.strings		= obex_string_defs,
};

static struct usb_gadget_strings *obex_strings[] = {
	&obex_string_table,
	NULL,
};

/*-------------------------------------------------------------------------*/

static struct usb_interface_descriptor obex_control_intf __initdata = {
	.bLength		= sizeof(obex_control_intf),
	.bDescriptorType	= USB_DT_INTERFACE,
	.bInterfaceNumber	= 0,

	.bAlternateSetting	= 0,
	.bNumEndpoints		= 0,
	.bInterfaceClass	= USB_CLASS_COMM,
	.bInterfaceSubClass	= USB_CDC_SUBCLASS_OBEX,
};

static struct usb_interface_descriptor obex_data_nop_intf __initdata = {
	.bLength		= sizeof(obex_data_nop_intf),
	.bDescriptorType	= USB_DT_INTERFACE,
	.bInterfaceNumber	= 1,

	.bAlternateSetting	= 0,
	.bNumEndpoints		= 0,
	.bInterfaceClass	= USB_CLASS_CDC_DATA,
};

static struct usb_interface_descriptor obex_data_intf __initdata = {
	.bLength		= sizeof(obex_data_intf),
	.bDescriptorType	= USB_DT_INTERFACE,
	.bInterfaceNumber	= 2,

	.bAlternateSetting	= 1,
	.bNumEndpoints		= 2,
	.bInterfaceClass	= USB_CLASS_CDC_DATA,
};

static struct usb_cdc_header_desc obex_cdc_header_desc __initdata = {
	.bLength		= sizeof(obex_cdc_header_desc),
	.bDescriptorType	= USB_DT_CS_INTERFACE,
	.bDescriptorSubType	= USB_CDC_HEADER_TYPE,
	.bcdCDC			= cpu_to_le16(0x0120),
};

static struct usb_cdc_union_desc obex_cdc_union_desc __initdata = {
	.bLength		= sizeof(obex_cdc_union_desc),
	.bDescriptorType	= USB_DT_CS_INTERFACE,
	.bDescriptorSubType	= USB_CDC_UNION_TYPE,
	.bMasterInterface0	= 1,
	.bSlaveInterface0	= 2,
};

static struct usb_cdc_obex_desc obex_desc __initdata = {
	.bLength		= sizeof(obex_desc),
	.bDescriptorType	= USB_DT_CS_INTERFACE,
	.bDescriptorSubType	= USB_CDC_OBEX_TYPE,
	.bcdVersion		= cpu_to_le16(0x0100),
};

/* High-Speed Support */

static struct usb_endpoint_descriptor obex_hs_ep_out_desc __initdata = {
	.bLength		= USB_DT_ENDPOINT_SIZE,
	.bDescriptorType	= USB_DT_ENDPOINT,

	.bEndpointAddress	= USB_DIR_OUT,
	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize		= cpu_to_le16(512),
};

static struct usb_endpoint_descriptor obex_hs_ep_in_desc __initdata = {
	.bLength		= USB_DT_ENDPOINT_SIZE,
	.bDescriptorType	= USB_DT_ENDPOINT,

	.bEndpointAddress	= USB_DIR_IN,
	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
	.wMaxPacketSize		= cpu_to_le16(512),
};

static struct usb_descriptor_header *hs_function[] __initdata = {
	(struct usb_descriptor_header *) &obex_control_intf,
	(struct usb_descriptor_header *) &obex_cdc_header_desc,
	(struct usb_descriptor_header *) &obex_desc,
	(struct usb_descriptor_header *) &obex_cdc_union_desc,

	(struct usb_descriptor_header *) &obex_data_nop_intf,
	(struct usb_descriptor_header *) &obex_data_intf,
	(struct usb_descriptor_header *) &obex_hs_ep_in_desc,
	(struct usb_descriptor_header *) &obex_hs_ep_out_desc,
	NULL,
};

/* Full-Speed Support */

static struct usb_endpoint_descriptor obex_fs_ep_in_desc __initdata = {
	.bLength		= USB_DT_ENDPOINT_SIZE,
	.bDescriptorType	= USB_DT_ENDPOINT,

	.bEndpointAddress	= USB_DIR_IN,
	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
};

static struct usb_endpoint_descriptor obex_fs_ep_out_desc __initdata = {
	.bLength		= USB_DT_ENDPOINT_SIZE,
	.bDescriptorType	= USB_DT_ENDPOINT,

	.bEndpointAddress	= USB_DIR_OUT,
	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
};

static struct usb_descriptor_header *fs_function[] __initdata = {
	(struct usb_descriptor_header *) &obex_control_intf,
	(struct usb_descriptor_header *) &obex_cdc_header_desc,
	(struct usb_descriptor_header *) &obex_desc,
	(struct usb_descriptor_header *) &obex_cdc_union_desc,

	(struct usb_descriptor_header *) &obex_data_nop_intf,
	(struct usb_descriptor_header *) &obex_data_intf,
	(struct usb_descriptor_header *) &obex_fs_ep_in_desc,
	(struct usb_descriptor_header *) &obex_fs_ep_out_desc,
	NULL,
};

/*-------------------------------------------------------------------------*/

static int obex_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
{
	struct f_obex		*obex = func_to_obex(f);
	struct usb_composite_dev *cdev = f->config->cdev;

	if (intf == obex->ctrl_id) {
		if (alt != 0)
			goto fail;
		/* NOP */
		DBG(cdev, "reset obex ttyGS%d control\n", obex->port_num);

	} else if (intf == obex->data_id) {
		if (alt > 1)
			goto fail;

		if (obex->port.in->driver_data) {
			DBG(cdev, "reset obex ttyGS%d\n", obex->port_num);
			gserial_disconnect(&obex->port);
		}

		if (!obex->port.in_desc) {
			DBG(cdev, "init obex ttyGS%d\n", obex->port_num);
			obex->port.in_desc = ep_choose(cdev->gadget,
					obex->hs.obex_in, obex->fs.obex_in);
			obex->port.out_desc = ep_choose(cdev->gadget,
					obex->hs.obex_out, obex->fs.obex_out);
		}

		if (alt == 1) {
			DBG(cdev, "activate obex ttyGS%d\n", obex->port_num);
			gserial_connect(&obex->port, obex->port_num);
		}

	} else
		goto fail;

	return 0;

fail:
	return -EINVAL;
}

static int obex_get_alt(struct usb_function *f, unsigned intf)
{
	struct f_obex		*obex = func_to_obex(f);

	if (intf == obex->ctrl_id)
		return 0;

	return obex->port.in->driver_data ? 1 : 0;
}

static void obex_disable(struct usb_function *f)
{
	struct f_obex	*obex = func_to_obex(f);
	struct usb_composite_dev *cdev = f->config->cdev;

	DBG(cdev, "obex ttyGS%d disable\n", obex->port_num);
	gserial_disconnect(&obex->port);
}

/*-------------------------------------------------------------------------*/

static void obex_connect(struct gserial *g)
{
	struct f_obex		*obex = port_to_obex(g);
	struct usb_composite_dev *cdev = g->func.config->cdev;
	int			status;

	if (!obex->can_activate)
		return;

	status = usb_function_activate(&g->func);
	if (status)
		DBG(cdev, "obex ttyGS%d function activate --> %d\n",
			obex->port_num, status);
}

static void obex_disconnect(struct gserial *g)
{
	struct f_obex		*obex = port_to_obex(g);
	struct usb_composite_dev *cdev = g->func.config->cdev;
	int			status;

	if (!obex->can_activate)
		return;

	status = usb_function_deactivate(&g->func);
	if (status)
		DBG(cdev, "obex ttyGS%d function deactivate --> %d\n",
			obex->port_num, status);
}

/*-------------------------------------------------------------------------*/

static int __init
obex_bind(struct usb_configuration *c, struct usb_function *f)
{
	struct usb_composite_dev *cdev = c->cdev;
	struct f_obex		*obex = func_to_obex(f);
	int			status;
	struct usb_ep		*ep;

	/* allocate instance-specific interface IDs, and patch descriptors */

	status = usb_interface_id(c, f);
	if (status < 0)
		goto fail;
	obex->ctrl_id = status;

	obex_control_intf.bInterfaceNumber = status;
	obex_cdc_union_desc.bMasterInterface0 = status;

	status = usb_interface_id(c, f);
	if (status < 0)
		goto fail;
	obex->data_id = status;

	obex_data_nop_intf.bInterfaceNumber = status;
	obex_data_intf.bInterfaceNumber = status;
	obex_cdc_union_desc.bSlaveInterface0 = status;

	/* allocate instance-specific endpoints */

	ep = usb_ep_autoconfig(cdev->gadget, &obex_fs_ep_in_desc);
	if (!ep)
		goto fail;
	obex->port.in = ep;
	ep->driver_data = cdev;	/* claim */

	ep = usb_ep_autoconfig(cdev->gadget, &obex_fs_ep_out_desc);
	if (!ep)
		goto fail;
	obex->port.out = ep;
	ep->driver_data = cdev;	/* claim */

	/* copy descriptors, and track endpoint copies */
	f->descriptors = usb_copy_descriptors(fs_function);

	obex->fs.obex_in = usb_find_endpoint(fs_function,
			f->descriptors, &obex_fs_ep_in_desc);
	obex->fs.obex_out = usb_find_endpoint(fs_function,
			f->descriptors, &obex_fs_ep_out_desc);

	/* support all relevant hardware speeds... we expect that when
	 * hardware is dual speed, all bulk-capable endpoints work at
	 * both speeds
	 */
	if (gadget_is_dualspeed(c->cdev->gadget)) {

		obex_hs_ep_in_desc.bEndpointAddress =
				obex_fs_ep_in_desc.bEndpointAddress;
		obex_hs_ep_out_desc.bEndpointAddress =
				obex_fs_ep_out_desc.bEndpointAddress;

		/* copy descriptors, and track endpoint copies */
		f->hs_descriptors = usb_copy_descriptors(hs_function);

		obex->hs.obex_in = usb_find_endpoint(hs_function,
				f->hs_descriptors, &obex_hs_ep_in_desc);
		obex->hs.obex_out = usb_find_endpoint(hs_function,
				f->hs_descriptors, &obex_hs_ep_out_desc);
	}

	/* Avoid letting this gadget enumerate until the userspace
	 * OBEX server is active.
	 */
	status = usb_function_deactivate(f);
	if (status < 0)
		WARNING(cdev, "obex ttyGS%d: can't prevent enumeration, %d\n",
			obex->port_num, status);
	else
		obex->can_activate = true;


	DBG(cdev, "obex ttyGS%d: %s speed IN/%s OUT/%s\n",
			obex->port_num,
			gadget_is_dualspeed(c->cdev->gadget) ? "dual" : "full",
			obex->port.in->name, obex->port.out->name);

	return 0;

fail:
	/* we might as well release our claims on endpoints */
	if (obex->port.out)
		obex->port.out->driver_data = NULL;
	if (obex->port.in)
		obex->port.in->driver_data = NULL;

	ERROR(cdev, "%s/%p: can't bind, err %d\n", f->name, f, status);

	return status;
}

static void
obex_unbind(struct usb_configuration *c, struct usb_function *f)
{
	if (gadget_is_dualspeed(c->cdev->gadget))
		usb_free_descriptors(f->hs_descriptors);
	usb_free_descriptors(f->descriptors);
	kfree(func_to_obex(f));
}

/* Some controllers can't support CDC OBEX ... */
static inline bool can_support_obex(struct usb_configuration *c)
{
	/* Since the first interface is a NOP, we can ignore the
	 * issue of multi-interface support on most controllers.
	 *
	 * Altsettings are mandatory, however...
	 */
	if (!gadget_supports_altsettings(c->cdev->gadget))
		return false;

	/* everything else is *probably* fine ... */
	return true;
}

/**
 * obex_bind_config - add a CDC OBEX function to a configuration
 * @c: the configuration to support the CDC OBEX instance
 * @port_num: /dev/ttyGS* port this interface will use
 * Context: single threaded during gadget setup
 *
 * Returns zero on success, else negative errno.
 *
 * Caller must have called @gserial_setup() with enough ports to
 * handle all the ones it binds.  Caller is also responsible
 * for calling @gserial_cleanup() before module unload.
 */
int __init obex_bind_config(struct usb_configuration *c, u8 port_num)
{
	struct f_obex	*obex;
	int		status;

	if (!can_support_obex(c))
		return -EINVAL;

	/* maybe allocate device-global string IDs, and patch descriptors */
	if (obex_string_defs[OBEX_CTRL_IDX].id == 0) {
		status = usb_string_id(c->cdev);
		if (status < 0)
			return status;
		obex_string_defs[OBEX_CTRL_IDX].id = status;

		obex_control_intf.iInterface = status;

		status = usb_string_id(c->cdev);
		if (status < 0)
			return status;
		obex_string_defs[OBEX_DATA_IDX].id = status;

		obex_data_nop_intf.iInterface =
			obex_data_intf.iInterface = status;
	}

	/* allocate and initialize one new instance */
	obex = kzalloc(sizeof *obex, GFP_KERNEL);
	if (!obex)
		return -ENOMEM;

	obex->port_num = port_num;

	obex->port.connect = obex_connect;
	obex->port.disconnect = obex_disconnect;

	obex->port.func.name = "obex";
	obex->port.func.strings = obex_strings;
	/* descriptors are per-instance copies */
	obex->port.func.bind = obex_bind;
	obex->port.func.unbind = obex_unbind;
	obex->port.func.set_alt = obex_set_alt;
	obex->port.func.get_alt = obex_get_alt;
	obex->port.func.disable = obex_disable;

	status = usb_add_function(c, &obex->port.func);
	if (status)
		kfree(obex);

	return status;
}

MODULE_AUTHOR("Felipe Balbi");
MODULE_LICENSE("GPL");