xref: /openbmc/u-boot/drivers/usb/gadget/f_dfu.c (revision 70ad375e)
1 /*
2  * f_dfu.c -- Device Firmware Update USB function
3  *
4  * Copyright (C) 2012 Samsung Electronics
5  * authors: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
6  *          Lukasz Majewski <l.majewski@samsung.com>
7  *
8  * Based on OpenMoko u-boot: drivers/usb/usbdfu.c
9  * (C) 2007 by OpenMoko, Inc.
10  * Author: Harald Welte <laforge@openmoko.org>
11  *
12  * based on existing SAM7DFU code from OpenPCD:
13  * (C) Copyright 2006 by Harald Welte <hwelte at hmw-consulting.de>
14  *
15  * SPDX-License-Identifier:	GPL-2.0+
16  */
17 
18 #include <errno.h>
19 #include <common.h>
20 #include <malloc.h>
21 
22 #include <linux/usb/ch9.h>
23 #include <linux/usb/gadget.h>
24 #include <linux/usb/composite.h>
25 
26 #include <dfu.h>
27 #include "f_dfu.h"
28 
29 struct f_dfu {
30 	struct usb_function		usb_function;
31 
32 	struct usb_descriptor_header	**function;
33 	struct usb_string		*strings;
34 
35 	/* when configured, we have one config */
36 	u8				config;
37 	u8				altsetting;
38 	enum dfu_state			dfu_state;
39 	unsigned int			dfu_status;
40 
41 	/* Send/received block number is handy for data integrity check */
42 	int                             blk_seq_num;
43 	unsigned int                    poll_timeout;
44 };
45 
46 typedef int (*dfu_state_fn) (struct f_dfu *,
47 			     const struct usb_ctrlrequest *,
48 			     struct usb_gadget *,
49 			     struct usb_request *);
50 
51 static inline struct f_dfu *func_to_dfu(struct usb_function *f)
52 {
53 	return container_of(f, struct f_dfu, usb_function);
54 }
55 
56 static const struct dfu_function_descriptor dfu_func = {
57 	.bLength =		sizeof dfu_func,
58 	.bDescriptorType =	DFU_DT_FUNC,
59 	.bmAttributes =		DFU_BIT_WILL_DETACH |
60 				DFU_BIT_MANIFESTATION_TOLERANT |
61 				DFU_BIT_CAN_UPLOAD |
62 				DFU_BIT_CAN_DNLOAD,
63 	.wDetachTimeOut =	0,
64 	.wTransferSize =	DFU_USB_BUFSIZ,
65 	.bcdDFUVersion =	__constant_cpu_to_le16(0x0110),
66 };
67 
68 static struct usb_interface_descriptor dfu_intf_runtime = {
69 	.bLength =		sizeof dfu_intf_runtime,
70 	.bDescriptorType =	USB_DT_INTERFACE,
71 	.bNumEndpoints =	0,
72 	.bInterfaceClass =	USB_CLASS_APP_SPEC,
73 	.bInterfaceSubClass =	1,
74 	.bInterfaceProtocol =	1,
75 	/* .iInterface = DYNAMIC */
76 };
77 
78 static struct usb_descriptor_header *dfu_runtime_descs[] = {
79 	(struct usb_descriptor_header *) &dfu_intf_runtime,
80 	NULL,
81 };
82 
83 static const struct usb_qualifier_descriptor dev_qualifier = {
84 	.bLength =		sizeof dev_qualifier,
85 	.bDescriptorType =	USB_DT_DEVICE_QUALIFIER,
86 	.bcdUSB =		__constant_cpu_to_le16(0x0200),
87 	.bDeviceClass =		USB_CLASS_VENDOR_SPEC,
88 	.bNumConfigurations =	1,
89 };
90 
91 static const char dfu_name[] = "Device Firmware Upgrade";
92 
93 /*
94  * static strings, in UTF-8
95  *
96  * dfu_generic configuration
97  */
98 static struct usb_string strings_dfu_generic[] = {
99 	[0].s = dfu_name,
100 	{  }			/* end of list */
101 };
102 
103 static struct usb_gadget_strings stringtab_dfu_generic = {
104 	.language	= 0x0409,	/* en-us */
105 	.strings	= strings_dfu_generic,
106 };
107 
108 static struct usb_gadget_strings *dfu_generic_strings[] = {
109 	&stringtab_dfu_generic,
110 	NULL,
111 };
112 
113 /*
114  * usb_function specific
115  */
116 static struct usb_gadget_strings stringtab_dfu = {
117 	.language	= 0x0409,	/* en-us */
118 	/*
119 	 * .strings
120 	 *
121 	 * assigned during initialization,
122 	 * depends on number of flash entities
123 	 *
124 	 */
125 };
126 
127 static struct usb_gadget_strings *dfu_strings[] = {
128 	&stringtab_dfu,
129 	NULL,
130 };
131 
132 static void dfu_set_poll_timeout(struct dfu_status *dstat, unsigned int ms)
133 {
134 	/*
135 	 * The bwPollTimeout DFU_GETSTATUS request payload provides information
136 	 * about minimum time, in milliseconds, that the host should wait before
137 	 * sending a subsequent DFU_GETSTATUS request
138 	 *
139 	 * This permits the device to vary the delay depending on its need to
140 	 * erase or program the memory
141 	 *
142 	 */
143 
144 	unsigned char *p = (unsigned char *)&ms;
145 
146 	if (!ms || (ms & ~DFU_POLL_TIMEOUT_MASK)) {
147 		dstat->bwPollTimeout[0] = 0;
148 		dstat->bwPollTimeout[1] = 0;
149 		dstat->bwPollTimeout[2] = 0;
150 
151 		return;
152 	}
153 
154 	dstat->bwPollTimeout[0] = *p++;
155 	dstat->bwPollTimeout[1] = *p++;
156 	dstat->bwPollTimeout[2] = *p;
157 }
158 
159 /*-------------------------------------------------------------------------*/
160 
161 static void dnload_request_complete(struct usb_ep *ep, struct usb_request *req)
162 {
163 	struct f_dfu *f_dfu = req->context;
164 
165 	dfu_write(dfu_get_entity(f_dfu->altsetting), req->buf,
166 		  req->length, f_dfu->blk_seq_num);
167 }
168 
169 static void dnload_request_flush(struct usb_ep *ep, struct usb_request *req)
170 {
171 	struct f_dfu *f_dfu = req->context;
172 
173 	dfu_flush(dfu_get_entity(f_dfu->altsetting), req->buf,
174 		  req->length, f_dfu->blk_seq_num);
175 }
176 
177 static void handle_getstatus(struct usb_request *req)
178 {
179 	struct dfu_status *dstat = (struct dfu_status *)req->buf;
180 	struct f_dfu *f_dfu = req->context;
181 
182 	dfu_set_poll_timeout(dstat, 0);
183 
184 	switch (f_dfu->dfu_state) {
185 	case DFU_STATE_dfuDNLOAD_SYNC:
186 	case DFU_STATE_dfuDNBUSY:
187 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_IDLE;
188 		break;
189 	case DFU_STATE_dfuMANIFEST_SYNC:
190 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST;
191 		break;
192 	case DFU_STATE_dfuMANIFEST:
193 		dfu_set_poll_timeout(dstat, DFU_MANIFEST_POLL_TIMEOUT);
194 	default:
195 		break;
196 	}
197 
198 	if (f_dfu->poll_timeout)
199 		if (!(f_dfu->blk_seq_num %
200 		      (dfu_get_buf_size() / DFU_USB_BUFSIZ)))
201 			dfu_set_poll_timeout(dstat, f_dfu->poll_timeout);
202 
203 	/* send status response */
204 	dstat->bStatus = f_dfu->dfu_status;
205 	dstat->bState = f_dfu->dfu_state;
206 	dstat->iString = 0;
207 }
208 
209 static void handle_getstate(struct usb_request *req)
210 {
211 	struct f_dfu *f_dfu = req->context;
212 
213 	((u8 *)req->buf)[0] = f_dfu->dfu_state;
214 	req->actual = sizeof(u8);
215 }
216 
217 static inline void to_dfu_mode(struct f_dfu *f_dfu)
218 {
219 	f_dfu->usb_function.strings = dfu_strings;
220 	f_dfu->usb_function.hs_descriptors = f_dfu->function;
221 	f_dfu->dfu_state = DFU_STATE_dfuIDLE;
222 }
223 
224 static inline void to_runtime_mode(struct f_dfu *f_dfu)
225 {
226 	f_dfu->usb_function.strings = NULL;
227 	f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
228 }
229 
230 static int handle_upload(struct usb_request *req, u16 len)
231 {
232 	struct f_dfu *f_dfu = req->context;
233 
234 	return dfu_read(dfu_get_entity(f_dfu->altsetting), req->buf,
235 			req->length, f_dfu->blk_seq_num);
236 }
237 
238 static int handle_dnload(struct usb_gadget *gadget, u16 len)
239 {
240 	struct usb_composite_dev *cdev = get_gadget_data(gadget);
241 	struct usb_request *req = cdev->req;
242 	struct f_dfu *f_dfu = req->context;
243 
244 	if (len == 0)
245 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST_SYNC;
246 
247 	req->complete = dnload_request_complete;
248 
249 	return len;
250 }
251 
252 /*-------------------------------------------------------------------------*/
253 /* DFU state machine  */
254 static int state_app_idle(struct f_dfu *f_dfu,
255 			  const struct usb_ctrlrequest *ctrl,
256 			  struct usb_gadget *gadget,
257 			  struct usb_request *req)
258 {
259 	int value = 0;
260 
261 	switch (ctrl->bRequest) {
262 	case USB_REQ_DFU_GETSTATUS:
263 		handle_getstatus(req);
264 		value = RET_STAT_LEN;
265 		break;
266 	case USB_REQ_DFU_GETSTATE:
267 		handle_getstate(req);
268 		break;
269 	case USB_REQ_DFU_DETACH:
270 		f_dfu->dfu_state = DFU_STATE_appDETACH;
271 		to_dfu_mode(f_dfu);
272 		value = RET_ZLP;
273 		break;
274 	default:
275 		value = RET_STALL;
276 		break;
277 	}
278 
279 	return value;
280 }
281 
282 static int state_app_detach(struct f_dfu *f_dfu,
283 			    const struct usb_ctrlrequest *ctrl,
284 			    struct usb_gadget *gadget,
285 			    struct usb_request *req)
286 {
287 	int value = 0;
288 
289 	switch (ctrl->bRequest) {
290 	case USB_REQ_DFU_GETSTATUS:
291 		handle_getstatus(req);
292 		value = RET_STAT_LEN;
293 		break;
294 	case USB_REQ_DFU_GETSTATE:
295 		handle_getstate(req);
296 		break;
297 	default:
298 		f_dfu->dfu_state = DFU_STATE_appIDLE;
299 		value = RET_STALL;
300 		break;
301 	}
302 
303 	return value;
304 }
305 
306 static int state_dfu_idle(struct f_dfu *f_dfu,
307 			  const struct usb_ctrlrequest *ctrl,
308 			  struct usb_gadget *gadget,
309 			  struct usb_request *req)
310 {
311 	u16 w_value = le16_to_cpu(ctrl->wValue);
312 	u16 len = le16_to_cpu(ctrl->wLength);
313 	int value = 0;
314 
315 	switch (ctrl->bRequest) {
316 	case USB_REQ_DFU_DNLOAD:
317 		if (len == 0) {
318 			f_dfu->dfu_state = DFU_STATE_dfuERROR;
319 			value = RET_STALL;
320 			break;
321 		}
322 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
323 		f_dfu->blk_seq_num = w_value;
324 		value = handle_dnload(gadget, len);
325 		break;
326 	case USB_REQ_DFU_UPLOAD:
327 		f_dfu->dfu_state = DFU_STATE_dfuUPLOAD_IDLE;
328 		f_dfu->blk_seq_num = 0;
329 		value = handle_upload(req, len);
330 		break;
331 	case USB_REQ_DFU_ABORT:
332 		/* no zlp? */
333 		value = RET_ZLP;
334 		break;
335 	case USB_REQ_DFU_GETSTATUS:
336 		handle_getstatus(req);
337 		value = RET_STAT_LEN;
338 		break;
339 	case USB_REQ_DFU_GETSTATE:
340 		handle_getstate(req);
341 		break;
342 	case USB_REQ_DFU_DETACH:
343 		/*
344 		 * Proprietary extension: 'detach' from idle mode and
345 		 * get back to runtime mode in case of USB Reset.  As
346 		 * much as I dislike this, we just can't use every USB
347 		 * bus reset to switch back to runtime mode, since at
348 		 * least the Linux USB stack likes to send a number of
349 		 * resets in a row :(
350 		 */
351 		f_dfu->dfu_state =
352 			DFU_STATE_dfuMANIFEST_WAIT_RST;
353 		to_runtime_mode(f_dfu);
354 		f_dfu->dfu_state = DFU_STATE_appIDLE;
355 
356 		dfu_trigger_reset();
357 		break;
358 	default:
359 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
360 		value = RET_STALL;
361 		break;
362 	}
363 
364 	return value;
365 }
366 
367 static int state_dfu_dnload_sync(struct f_dfu *f_dfu,
368 				 const struct usb_ctrlrequest *ctrl,
369 				 struct usb_gadget *gadget,
370 				 struct usb_request *req)
371 {
372 	int value = 0;
373 
374 	switch (ctrl->bRequest) {
375 	case USB_REQ_DFU_GETSTATUS:
376 		handle_getstatus(req);
377 		value = RET_STAT_LEN;
378 		break;
379 	case USB_REQ_DFU_GETSTATE:
380 		handle_getstate(req);
381 		break;
382 	default:
383 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
384 		value = RET_STALL;
385 		break;
386 	}
387 
388 	return value;
389 }
390 
391 static int state_dfu_dnbusy(struct f_dfu *f_dfu,
392 			    const struct usb_ctrlrequest *ctrl,
393 			    struct usb_gadget *gadget,
394 			    struct usb_request *req)
395 {
396 	int value = 0;
397 
398 	switch (ctrl->bRequest) {
399 	case USB_REQ_DFU_GETSTATUS:
400 		handle_getstatus(req);
401 		value = RET_STAT_LEN;
402 		break;
403 	default:
404 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
405 		value = RET_STALL;
406 		break;
407 	}
408 
409 	return value;
410 }
411 
412 static int state_dfu_dnload_idle(struct f_dfu *f_dfu,
413 				 const struct usb_ctrlrequest *ctrl,
414 				 struct usb_gadget *gadget,
415 				 struct usb_request *req)
416 {
417 	u16 w_value = le16_to_cpu(ctrl->wValue);
418 	u16 len = le16_to_cpu(ctrl->wLength);
419 	int value = 0;
420 
421 	switch (ctrl->bRequest) {
422 	case USB_REQ_DFU_DNLOAD:
423 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
424 		f_dfu->blk_seq_num = w_value;
425 		value = handle_dnload(gadget, len);
426 		break;
427 	case USB_REQ_DFU_ABORT:
428 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
429 		value = RET_ZLP;
430 		break;
431 	case USB_REQ_DFU_GETSTATUS:
432 		handle_getstatus(req);
433 		value = RET_STAT_LEN;
434 		break;
435 	case USB_REQ_DFU_GETSTATE:
436 		handle_getstate(req);
437 		break;
438 	default:
439 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
440 		value = RET_STALL;
441 		break;
442 	}
443 
444 	return value;
445 }
446 
447 static int state_dfu_manifest_sync(struct f_dfu *f_dfu,
448 				   const struct usb_ctrlrequest *ctrl,
449 				   struct usb_gadget *gadget,
450 				   struct usb_request *req)
451 {
452 	int value = 0;
453 
454 	switch (ctrl->bRequest) {
455 	case USB_REQ_DFU_GETSTATUS:
456 		/* We're MainfestationTolerant */
457 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST;
458 		handle_getstatus(req);
459 		f_dfu->blk_seq_num = 0;
460 		value = RET_STAT_LEN;
461 		req->complete = dnload_request_flush;
462 		break;
463 	case USB_REQ_DFU_GETSTATE:
464 		handle_getstate(req);
465 		break;
466 	default:
467 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
468 		value = RET_STALL;
469 		break;
470 	}
471 
472 	return value;
473 }
474 
475 static int state_dfu_manifest(struct f_dfu *f_dfu,
476 			      const struct usb_ctrlrequest *ctrl,
477 			      struct usb_gadget *gadget,
478 			      struct usb_request *req)
479 {
480 	int value = 0;
481 
482 	switch (ctrl->bRequest) {
483 	case USB_REQ_DFU_GETSTATUS:
484 		/* We're MainfestationTolerant */
485 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
486 		handle_getstatus(req);
487 		f_dfu->blk_seq_num = 0;
488 		value = RET_STAT_LEN;
489 		puts("DOWNLOAD ... OK\nCtrl+C to exit ...\n");
490 		break;
491 	case USB_REQ_DFU_GETSTATE:
492 		handle_getstate(req);
493 		break;
494 	default:
495 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
496 		value = RET_STALL;
497 		break;
498 	}
499 	return value;
500 }
501 
502 static int state_dfu_upload_idle(struct f_dfu *f_dfu,
503 				 const struct usb_ctrlrequest *ctrl,
504 				 struct usb_gadget *gadget,
505 				 struct usb_request *req)
506 {
507 	u16 w_value = le16_to_cpu(ctrl->wValue);
508 	u16 len = le16_to_cpu(ctrl->wLength);
509 	int value = 0;
510 
511 	switch (ctrl->bRequest) {
512 	case USB_REQ_DFU_UPLOAD:
513 		/* state transition if less data then requested */
514 		f_dfu->blk_seq_num = w_value;
515 		value = handle_upload(req, len);
516 		if (value >= 0 && value < len)
517 			f_dfu->dfu_state = DFU_STATE_dfuIDLE;
518 		break;
519 	case USB_REQ_DFU_ABORT:
520 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
521 		/* no zlp? */
522 		value = RET_ZLP;
523 		break;
524 	case USB_REQ_DFU_GETSTATUS:
525 		handle_getstatus(req);
526 		value = RET_STAT_LEN;
527 		break;
528 	case USB_REQ_DFU_GETSTATE:
529 		handle_getstate(req);
530 		break;
531 	default:
532 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
533 		value = RET_STALL;
534 		break;
535 	}
536 
537 	return value;
538 }
539 
540 static int state_dfu_error(struct f_dfu *f_dfu,
541 				 const struct usb_ctrlrequest *ctrl,
542 				 struct usb_gadget *gadget,
543 				 struct usb_request *req)
544 {
545 	int value = 0;
546 
547 	switch (ctrl->bRequest) {
548 	case USB_REQ_DFU_GETSTATUS:
549 		handle_getstatus(req);
550 		value = RET_STAT_LEN;
551 		break;
552 	case USB_REQ_DFU_GETSTATE:
553 		handle_getstate(req);
554 		break;
555 	case USB_REQ_DFU_CLRSTATUS:
556 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
557 		f_dfu->dfu_status = DFU_STATUS_OK;
558 		/* no zlp? */
559 		value = RET_ZLP;
560 		break;
561 	default:
562 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
563 		value = RET_STALL;
564 		break;
565 	}
566 
567 	return value;
568 }
569 
570 static dfu_state_fn dfu_state[] = {
571 	state_app_idle,          /* DFU_STATE_appIDLE */
572 	state_app_detach,        /* DFU_STATE_appDETACH */
573 	state_dfu_idle,          /* DFU_STATE_dfuIDLE */
574 	state_dfu_dnload_sync,   /* DFU_STATE_dfuDNLOAD_SYNC */
575 	state_dfu_dnbusy,        /* DFU_STATE_dfuDNBUSY */
576 	state_dfu_dnload_idle,   /* DFU_STATE_dfuDNLOAD_IDLE */
577 	state_dfu_manifest_sync, /* DFU_STATE_dfuMANIFEST_SYNC */
578 	state_dfu_manifest,	 /* DFU_STATE_dfuMANIFEST */
579 	NULL,                    /* DFU_STATE_dfuMANIFEST_WAIT_RST */
580 	state_dfu_upload_idle,   /* DFU_STATE_dfuUPLOAD_IDLE */
581 	state_dfu_error          /* DFU_STATE_dfuERROR */
582 };
583 
584 static int
585 dfu_handle(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
586 {
587 	struct usb_gadget *gadget = f->config->cdev->gadget;
588 	struct usb_request *req = f->config->cdev->req;
589 	struct f_dfu *f_dfu = f->config->cdev->req->context;
590 	u16 len = le16_to_cpu(ctrl->wLength);
591 	u16 w_value = le16_to_cpu(ctrl->wValue);
592 	int value = 0;
593 	u8 req_type = ctrl->bRequestType & USB_TYPE_MASK;
594 
595 	debug("w_value: 0x%x len: 0x%x\n", w_value, len);
596 	debug("req_type: 0x%x ctrl->bRequest: 0x%x f_dfu->dfu_state: 0x%x\n",
597 	       req_type, ctrl->bRequest, f_dfu->dfu_state);
598 
599 	if (req_type == USB_TYPE_STANDARD) {
600 		if (ctrl->bRequest == USB_REQ_GET_DESCRIPTOR &&
601 		    (w_value >> 8) == DFU_DT_FUNC) {
602 			value = min(len, (u16) sizeof(dfu_func));
603 			memcpy(req->buf, &dfu_func, value);
604 		}
605 	} else /* DFU specific request */
606 		value = dfu_state[f_dfu->dfu_state] (f_dfu, ctrl, gadget, req);
607 
608 	if (value >= 0) {
609 		req->length = value;
610 		req->zero = value < len;
611 		value = usb_ep_queue(gadget->ep0, req, 0);
612 		if (value < 0) {
613 			debug("ep_queue --> %d\n", value);
614 			req->status = 0;
615 		}
616 	}
617 
618 	return value;
619 }
620 
621 /*-------------------------------------------------------------------------*/
622 
623 static int
624 dfu_prepare_strings(struct f_dfu *f_dfu, int n)
625 {
626 	struct dfu_entity *de = NULL;
627 	int i = 0;
628 
629 	f_dfu->strings = calloc(sizeof(struct usb_string), n + 1);
630 	if (!f_dfu->strings)
631 		goto enomem;
632 
633 	for (i = 0; i < n; ++i) {
634 		de = dfu_get_entity(i);
635 		f_dfu->strings[i].s = de->name;
636 	}
637 
638 	f_dfu->strings[i].id = 0;
639 	f_dfu->strings[i].s = NULL;
640 
641 	return 0;
642 
643 enomem:
644 	while (i)
645 		f_dfu->strings[--i].s = NULL;
646 
647 	free(f_dfu->strings);
648 
649 	return -ENOMEM;
650 }
651 
652 static int dfu_prepare_function(struct f_dfu *f_dfu, int n)
653 {
654 	struct usb_interface_descriptor *d;
655 	int i = 0;
656 
657 	f_dfu->function = calloc(sizeof(struct usb_descriptor_header *), n + 1);
658 	if (!f_dfu->function)
659 		goto enomem;
660 
661 	for (i = 0; i < n; ++i) {
662 		d = calloc(sizeof(*d), 1);
663 		if (!d)
664 			goto enomem;
665 
666 		d->bLength =		sizeof(*d);
667 		d->bDescriptorType =	USB_DT_INTERFACE;
668 		d->bAlternateSetting =	i;
669 		d->bNumEndpoints =	0;
670 		d->bInterfaceClass =	USB_CLASS_APP_SPEC;
671 		d->bInterfaceSubClass =	1;
672 		d->bInterfaceProtocol =	2;
673 
674 		f_dfu->function[i] = (struct usb_descriptor_header *)d;
675 	}
676 	f_dfu->function[i] = NULL;
677 
678 	return 0;
679 
680 enomem:
681 	while (i) {
682 		free(f_dfu->function[--i]);
683 		f_dfu->function[i] = NULL;
684 	}
685 	free(f_dfu->function);
686 
687 	return -ENOMEM;
688 }
689 
690 static int dfu_bind(struct usb_configuration *c, struct usb_function *f)
691 {
692 	struct usb_composite_dev *cdev = c->cdev;
693 	struct f_dfu *f_dfu = func_to_dfu(f);
694 	int alt_num = dfu_get_alt_number();
695 	int rv, id, i;
696 
697 	id = usb_interface_id(c, f);
698 	if (id < 0)
699 		return id;
700 	dfu_intf_runtime.bInterfaceNumber = id;
701 
702 	f_dfu->dfu_state = DFU_STATE_appIDLE;
703 	f_dfu->dfu_status = DFU_STATUS_OK;
704 
705 	rv = dfu_prepare_function(f_dfu, alt_num);
706 	if (rv)
707 		goto error;
708 
709 	rv = dfu_prepare_strings(f_dfu, alt_num);
710 	if (rv)
711 		goto error;
712 	for (i = 0; i < alt_num; i++) {
713 		id = usb_string_id(cdev);
714 		if (id < 0)
715 			return id;
716 		f_dfu->strings[i].id = id;
717 		((struct usb_interface_descriptor *)f_dfu->function[i])
718 			->iInterface = id;
719 	}
720 
721 	to_dfu_mode(f_dfu);
722 
723 	stringtab_dfu.strings = f_dfu->strings;
724 
725 	cdev->req->context = f_dfu;
726 
727 error:
728 	return rv;
729 }
730 
731 static void dfu_unbind(struct usb_configuration *c, struct usb_function *f)
732 {
733 	struct f_dfu *f_dfu = func_to_dfu(f);
734 	int alt_num = dfu_get_alt_number();
735 	int i;
736 
737 	if (f_dfu->strings) {
738 		i = alt_num;
739 		while (i)
740 			f_dfu->strings[--i].s = NULL;
741 
742 		free(f_dfu->strings);
743 	}
744 
745 	if (f_dfu->function) {
746 		i = alt_num;
747 		while (i) {
748 			free(f_dfu->function[--i]);
749 			f_dfu->function[i] = NULL;
750 		}
751 		free(f_dfu->function);
752 	}
753 
754 	free(f_dfu);
755 }
756 
757 static int dfu_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
758 {
759 	struct f_dfu *f_dfu = func_to_dfu(f);
760 
761 	debug("%s: intf:%d alt:%d\n", __func__, intf, alt);
762 
763 	f_dfu->altsetting = alt;
764 
765 	return 0;
766 }
767 
768 /* TODO: is this really what we need here? */
769 static void dfu_disable(struct usb_function *f)
770 {
771 	struct f_dfu *f_dfu = func_to_dfu(f);
772 	if (f_dfu->config == 0)
773 		return;
774 
775 	debug("%s: reset config\n", __func__);
776 
777 	f_dfu->config = 0;
778 }
779 
780 static int dfu_bind_config(struct usb_configuration *c)
781 {
782 	struct f_dfu *f_dfu;
783 	int status;
784 
785 	f_dfu = calloc(sizeof(*f_dfu), 1);
786 	if (!f_dfu)
787 		return -ENOMEM;
788 	f_dfu->usb_function.name = "dfu";
789 	f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
790 	f_dfu->usb_function.bind = dfu_bind;
791 	f_dfu->usb_function.unbind = dfu_unbind;
792 	f_dfu->usb_function.set_alt = dfu_set_alt;
793 	f_dfu->usb_function.disable = dfu_disable;
794 	f_dfu->usb_function.strings = dfu_generic_strings;
795 	f_dfu->usb_function.setup = dfu_handle;
796 	f_dfu->poll_timeout = DFU_DEFAULT_POLL_TIMEOUT;
797 
798 	status = usb_add_function(c, &f_dfu->usb_function);
799 	if (status)
800 		free(f_dfu);
801 
802 	return status;
803 }
804 
805 int dfu_add(struct usb_configuration *c)
806 {
807 	int id;
808 
809 	id = usb_string_id(c->cdev);
810 	if (id < 0)
811 		return id;
812 	strings_dfu_generic[0].id = id;
813 	dfu_intf_runtime.iInterface = id;
814 
815 	debug("%s: cdev: 0x%p gadget:0x%p gadget->ep0: 0x%p\n", __func__,
816 	       c->cdev, c->cdev->gadget, c->cdev->gadget->ep0);
817 
818 	return dfu_bind_config(c);
819 }
820