xref: /openbmc/u-boot/drivers/usb/gadget/f_dfu.c (revision 699c4e59)
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 <g_dnl.h>
28 #include "f_dfu.h"
29 
30 struct f_dfu {
31 	struct usb_function		usb_function;
32 
33 	struct usb_descriptor_header	**function;
34 	struct usb_string		*strings;
35 
36 	/* when configured, we have one config */
37 	u8				config;
38 	u8				altsetting;
39 	enum dfu_state			dfu_state;
40 	unsigned int			dfu_status;
41 
42 	/* Send/received block number is handy for data integrity check */
43 	int                             blk_seq_num;
44 	unsigned int                    poll_timeout;
45 };
46 
47 struct dfu_entity *dfu_defer_flush;
48 
49 typedef int (*dfu_state_fn) (struct f_dfu *,
50 			     const struct usb_ctrlrequest *,
51 			     struct usb_gadget *,
52 			     struct usb_request *);
53 
54 static inline struct f_dfu *func_to_dfu(struct usb_function *f)
55 {
56 	return container_of(f, struct f_dfu, usb_function);
57 }
58 
59 static const struct dfu_function_descriptor dfu_func = {
60 	.bLength =		sizeof dfu_func,
61 	.bDescriptorType =	DFU_DT_FUNC,
62 	.bmAttributes =		DFU_BIT_WILL_DETACH |
63 				DFU_BIT_MANIFESTATION_TOLERANT |
64 				DFU_BIT_CAN_UPLOAD |
65 				DFU_BIT_CAN_DNLOAD,
66 	.wDetachTimeOut =	0,
67 	.wTransferSize =	DFU_USB_BUFSIZ,
68 	.bcdDFUVersion =	__constant_cpu_to_le16(0x0110),
69 };
70 
71 static struct usb_interface_descriptor dfu_intf_runtime = {
72 	.bLength =		sizeof dfu_intf_runtime,
73 	.bDescriptorType =	USB_DT_INTERFACE,
74 	.bNumEndpoints =	0,
75 	.bInterfaceClass =	USB_CLASS_APP_SPEC,
76 	.bInterfaceSubClass =	1,
77 	.bInterfaceProtocol =	1,
78 	/* .iInterface = DYNAMIC */
79 };
80 
81 static struct usb_descriptor_header *dfu_runtime_descs[] = {
82 	(struct usb_descriptor_header *) &dfu_intf_runtime,
83 	NULL,
84 };
85 
86 static const char dfu_name[] = "Device Firmware Upgrade";
87 
88 /*
89  * static strings, in UTF-8
90  *
91  * dfu_generic configuration
92  */
93 static struct usb_string strings_dfu_generic[] = {
94 	[0].s = dfu_name,
95 	{  }			/* end of list */
96 };
97 
98 static struct usb_gadget_strings stringtab_dfu_generic = {
99 	.language	= 0x0409,	/* en-us */
100 	.strings	= strings_dfu_generic,
101 };
102 
103 static struct usb_gadget_strings *dfu_generic_strings[] = {
104 	&stringtab_dfu_generic,
105 	NULL,
106 };
107 
108 /*
109  * usb_function specific
110  */
111 static struct usb_gadget_strings stringtab_dfu = {
112 	.language	= 0x0409,	/* en-us */
113 	/*
114 	 * .strings
115 	 *
116 	 * assigned during initialization,
117 	 * depends on number of flash entities
118 	 *
119 	 */
120 };
121 
122 static struct usb_gadget_strings *dfu_strings[] = {
123 	&stringtab_dfu,
124 	NULL,
125 };
126 
127 static void dfu_set_poll_timeout(struct dfu_status *dstat, unsigned int ms)
128 {
129 	/*
130 	 * The bwPollTimeout DFU_GETSTATUS request payload provides information
131 	 * about minimum time, in milliseconds, that the host should wait before
132 	 * sending a subsequent DFU_GETSTATUS request
133 	 *
134 	 * This permits the device to vary the delay depending on its need to
135 	 * erase or program the memory
136 	 *
137 	 */
138 
139 	unsigned char *p = (unsigned char *)&ms;
140 
141 	if (!ms || (ms & ~DFU_POLL_TIMEOUT_MASK)) {
142 		dstat->bwPollTimeout[0] = 0;
143 		dstat->bwPollTimeout[1] = 0;
144 		dstat->bwPollTimeout[2] = 0;
145 
146 		return;
147 	}
148 
149 	dstat->bwPollTimeout[0] = *p++;
150 	dstat->bwPollTimeout[1] = *p++;
151 	dstat->bwPollTimeout[2] = *p;
152 }
153 
154 /*-------------------------------------------------------------------------*/
155 
156 static void dnload_request_complete(struct usb_ep *ep, struct usb_request *req)
157 {
158 	struct f_dfu *f_dfu = req->context;
159 	int ret;
160 
161 	ret = dfu_write(dfu_get_entity(f_dfu->altsetting), req->buf,
162 			req->length, f_dfu->blk_seq_num);
163 	if (ret) {
164 		f_dfu->dfu_status = DFU_STATUS_errUNKNOWN;
165 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
166 	}
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 	dfu_set_defer_flush(dfu_get_entity(f_dfu->altsetting));
173 }
174 
175 static inline int dfu_get_manifest_timeout(struct dfu_entity *dfu)
176 {
177 	return dfu->poll_timeout ? dfu->poll_timeout(dfu) :
178 		DFU_MANIFEST_POLL_TIMEOUT;
179 }
180 
181 static void handle_getstatus(struct usb_request *req)
182 {
183 	struct dfu_status *dstat = (struct dfu_status *)req->buf;
184 	struct f_dfu *f_dfu = req->context;
185 	struct dfu_entity *dfu = dfu_get_entity(f_dfu->altsetting);
186 
187 	dfu_set_poll_timeout(dstat, 0);
188 
189 	switch (f_dfu->dfu_state) {
190 	case DFU_STATE_dfuDNLOAD_SYNC:
191 	case DFU_STATE_dfuDNBUSY:
192 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_IDLE;
193 		break;
194 	case DFU_STATE_dfuMANIFEST_SYNC:
195 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST;
196 		break;
197 	case DFU_STATE_dfuMANIFEST:
198 		dfu_set_poll_timeout(dstat, dfu_get_manifest_timeout(dfu));
199 		break;
200 	default:
201 		break;
202 	}
203 
204 	if (f_dfu->poll_timeout)
205 		if (!(f_dfu->blk_seq_num %
206 		      (dfu_get_buf_size() / DFU_USB_BUFSIZ)))
207 			dfu_set_poll_timeout(dstat, f_dfu->poll_timeout);
208 
209 	/* send status response */
210 	dstat->bStatus = f_dfu->dfu_status;
211 	dstat->bState = f_dfu->dfu_state;
212 	dstat->iString = 0;
213 }
214 
215 static void handle_getstate(struct usb_request *req)
216 {
217 	struct f_dfu *f_dfu = req->context;
218 
219 	((u8 *)req->buf)[0] = f_dfu->dfu_state;
220 	req->actual = sizeof(u8);
221 }
222 
223 static inline void to_dfu_mode(struct f_dfu *f_dfu)
224 {
225 	f_dfu->usb_function.strings = dfu_strings;
226 	f_dfu->usb_function.hs_descriptors = f_dfu->function;
227 	f_dfu->usb_function.descriptors = f_dfu->function;
228 	f_dfu->dfu_state = DFU_STATE_dfuIDLE;
229 }
230 
231 static inline void to_runtime_mode(struct f_dfu *f_dfu)
232 {
233 	f_dfu->usb_function.strings = NULL;
234 	f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
235 	f_dfu->usb_function.descriptors = dfu_runtime_descs;
236 }
237 
238 static int handle_upload(struct usb_request *req, u16 len)
239 {
240 	struct f_dfu *f_dfu = req->context;
241 
242 	return dfu_read(dfu_get_entity(f_dfu->altsetting), req->buf,
243 			req->length, f_dfu->blk_seq_num);
244 }
245 
246 static int handle_dnload(struct usb_gadget *gadget, u16 len)
247 {
248 	struct usb_composite_dev *cdev = get_gadget_data(gadget);
249 	struct usb_request *req = cdev->req;
250 	struct f_dfu *f_dfu = req->context;
251 
252 	if (len == 0)
253 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST_SYNC;
254 
255 	req->complete = dnload_request_complete;
256 
257 	return len;
258 }
259 
260 /*-------------------------------------------------------------------------*/
261 /* DFU state machine  */
262 static int state_app_idle(struct f_dfu *f_dfu,
263 			  const struct usb_ctrlrequest *ctrl,
264 			  struct usb_gadget *gadget,
265 			  struct usb_request *req)
266 {
267 	int value = 0;
268 
269 	switch (ctrl->bRequest) {
270 	case USB_REQ_DFU_GETSTATUS:
271 		handle_getstatus(req);
272 		value = RET_STAT_LEN;
273 		break;
274 	case USB_REQ_DFU_GETSTATE:
275 		handle_getstate(req);
276 		break;
277 	case USB_REQ_DFU_DETACH:
278 		f_dfu->dfu_state = DFU_STATE_appDETACH;
279 		to_dfu_mode(f_dfu);
280 		value = RET_ZLP;
281 		break;
282 	default:
283 		value = RET_STALL;
284 		break;
285 	}
286 
287 	return value;
288 }
289 
290 static int state_app_detach(struct f_dfu *f_dfu,
291 			    const struct usb_ctrlrequest *ctrl,
292 			    struct usb_gadget *gadget,
293 			    struct usb_request *req)
294 {
295 	int value = 0;
296 
297 	switch (ctrl->bRequest) {
298 	case USB_REQ_DFU_GETSTATUS:
299 		handle_getstatus(req);
300 		value = RET_STAT_LEN;
301 		break;
302 	case USB_REQ_DFU_GETSTATE:
303 		handle_getstate(req);
304 		break;
305 	default:
306 		f_dfu->dfu_state = DFU_STATE_appIDLE;
307 		value = RET_STALL;
308 		break;
309 	}
310 
311 	return value;
312 }
313 
314 static int state_dfu_idle(struct f_dfu *f_dfu,
315 			  const struct usb_ctrlrequest *ctrl,
316 			  struct usb_gadget *gadget,
317 			  struct usb_request *req)
318 {
319 	u16 w_value = le16_to_cpu(ctrl->wValue);
320 	u16 len = le16_to_cpu(ctrl->wLength);
321 	int value = 0;
322 
323 	switch (ctrl->bRequest) {
324 	case USB_REQ_DFU_DNLOAD:
325 		if (len == 0) {
326 			f_dfu->dfu_state = DFU_STATE_dfuERROR;
327 			value = RET_STALL;
328 			break;
329 		}
330 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
331 		f_dfu->blk_seq_num = w_value;
332 		value = handle_dnload(gadget, len);
333 		break;
334 	case USB_REQ_DFU_UPLOAD:
335 		f_dfu->dfu_state = DFU_STATE_dfuUPLOAD_IDLE;
336 		f_dfu->blk_seq_num = 0;
337 		value = handle_upload(req, len);
338 		break;
339 	case USB_REQ_DFU_ABORT:
340 		/* no zlp? */
341 		value = RET_ZLP;
342 		break;
343 	case USB_REQ_DFU_GETSTATUS:
344 		handle_getstatus(req);
345 		value = RET_STAT_LEN;
346 		break;
347 	case USB_REQ_DFU_GETSTATE:
348 		handle_getstate(req);
349 		break;
350 	case USB_REQ_DFU_DETACH:
351 		/*
352 		 * Proprietary extension: 'detach' from idle mode and
353 		 * get back to runtime mode in case of USB Reset.  As
354 		 * much as I dislike this, we just can't use every USB
355 		 * bus reset to switch back to runtime mode, since at
356 		 * least the Linux USB stack likes to send a number of
357 		 * resets in a row :(
358 		 */
359 		f_dfu->dfu_state =
360 			DFU_STATE_dfuMANIFEST_WAIT_RST;
361 		to_runtime_mode(f_dfu);
362 		f_dfu->dfu_state = DFU_STATE_appIDLE;
363 
364 		g_dnl_trigger_detach();
365 		break;
366 	default:
367 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
368 		value = RET_STALL;
369 		break;
370 	}
371 
372 	return value;
373 }
374 
375 static int state_dfu_dnload_sync(struct f_dfu *f_dfu,
376 				 const struct usb_ctrlrequest *ctrl,
377 				 struct usb_gadget *gadget,
378 				 struct usb_request *req)
379 {
380 	int value = 0;
381 
382 	switch (ctrl->bRequest) {
383 	case USB_REQ_DFU_GETSTATUS:
384 		handle_getstatus(req);
385 		value = RET_STAT_LEN;
386 		break;
387 	case USB_REQ_DFU_GETSTATE:
388 		handle_getstate(req);
389 		break;
390 	default:
391 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
392 		value = RET_STALL;
393 		break;
394 	}
395 
396 	return value;
397 }
398 
399 static int state_dfu_dnbusy(struct f_dfu *f_dfu,
400 			    const struct usb_ctrlrequest *ctrl,
401 			    struct usb_gadget *gadget,
402 			    struct usb_request *req)
403 {
404 	int value = 0;
405 
406 	switch (ctrl->bRequest) {
407 	case USB_REQ_DFU_GETSTATUS:
408 		handle_getstatus(req);
409 		value = RET_STAT_LEN;
410 		break;
411 	default:
412 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
413 		value = RET_STALL;
414 		break;
415 	}
416 
417 	return value;
418 }
419 
420 static int state_dfu_dnload_idle(struct f_dfu *f_dfu,
421 				 const struct usb_ctrlrequest *ctrl,
422 				 struct usb_gadget *gadget,
423 				 struct usb_request *req)
424 {
425 	u16 w_value = le16_to_cpu(ctrl->wValue);
426 	u16 len = le16_to_cpu(ctrl->wLength);
427 	int value = 0;
428 
429 	switch (ctrl->bRequest) {
430 	case USB_REQ_DFU_DNLOAD:
431 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
432 		f_dfu->blk_seq_num = w_value;
433 		value = handle_dnload(gadget, len);
434 		break;
435 	case USB_REQ_DFU_ABORT:
436 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
437 		value = RET_ZLP;
438 		break;
439 	case USB_REQ_DFU_GETSTATUS:
440 		handle_getstatus(req);
441 		value = RET_STAT_LEN;
442 		break;
443 	case USB_REQ_DFU_GETSTATE:
444 		handle_getstate(req);
445 		break;
446 	default:
447 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
448 		value = RET_STALL;
449 		break;
450 	}
451 
452 	return value;
453 }
454 
455 static int state_dfu_manifest_sync(struct f_dfu *f_dfu,
456 				   const struct usb_ctrlrequest *ctrl,
457 				   struct usb_gadget *gadget,
458 				   struct usb_request *req)
459 {
460 	int value = 0;
461 
462 	switch (ctrl->bRequest) {
463 	case USB_REQ_DFU_GETSTATUS:
464 		/* We're MainfestationTolerant */
465 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST;
466 		handle_getstatus(req);
467 		f_dfu->blk_seq_num = 0;
468 		value = RET_STAT_LEN;
469 		req->complete = dnload_request_flush;
470 		break;
471 	case USB_REQ_DFU_GETSTATE:
472 		handle_getstate(req);
473 		break;
474 	default:
475 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
476 		value = RET_STALL;
477 		break;
478 	}
479 
480 	return value;
481 }
482 
483 static int state_dfu_manifest(struct f_dfu *f_dfu,
484 			      const struct usb_ctrlrequest *ctrl,
485 			      struct usb_gadget *gadget,
486 			      struct usb_request *req)
487 {
488 	int value = 0;
489 
490 	switch (ctrl->bRequest) {
491 	case USB_REQ_DFU_GETSTATUS:
492 		/* We're MainfestationTolerant */
493 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
494 		handle_getstatus(req);
495 		f_dfu->blk_seq_num = 0;
496 		value = RET_STAT_LEN;
497 		puts("DOWNLOAD ... OK\nCtrl+C to exit ...\n");
498 		break;
499 	case USB_REQ_DFU_GETSTATE:
500 		handle_getstate(req);
501 		break;
502 	default:
503 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
504 		value = RET_STALL;
505 		break;
506 	}
507 	return value;
508 }
509 
510 static int state_dfu_upload_idle(struct f_dfu *f_dfu,
511 				 const struct usb_ctrlrequest *ctrl,
512 				 struct usb_gadget *gadget,
513 				 struct usb_request *req)
514 {
515 	u16 w_value = le16_to_cpu(ctrl->wValue);
516 	u16 len = le16_to_cpu(ctrl->wLength);
517 	int value = 0;
518 
519 	switch (ctrl->bRequest) {
520 	case USB_REQ_DFU_UPLOAD:
521 		/* state transition if less data then requested */
522 		f_dfu->blk_seq_num = w_value;
523 		value = handle_upload(req, len);
524 		if (value >= 0 && value < len)
525 			f_dfu->dfu_state = DFU_STATE_dfuIDLE;
526 		break;
527 	case USB_REQ_DFU_ABORT:
528 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
529 		/* no zlp? */
530 		value = RET_ZLP;
531 		break;
532 	case USB_REQ_DFU_GETSTATUS:
533 		handle_getstatus(req);
534 		value = RET_STAT_LEN;
535 		break;
536 	case USB_REQ_DFU_GETSTATE:
537 		handle_getstate(req);
538 		break;
539 	default:
540 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
541 		value = RET_STALL;
542 		break;
543 	}
544 
545 	return value;
546 }
547 
548 static int state_dfu_error(struct f_dfu *f_dfu,
549 				 const struct usb_ctrlrequest *ctrl,
550 				 struct usb_gadget *gadget,
551 				 struct usb_request *req)
552 {
553 	int value = 0;
554 
555 	switch (ctrl->bRequest) {
556 	case USB_REQ_DFU_GETSTATUS:
557 		handle_getstatus(req);
558 		value = RET_STAT_LEN;
559 		break;
560 	case USB_REQ_DFU_GETSTATE:
561 		handle_getstate(req);
562 		break;
563 	case USB_REQ_DFU_CLRSTATUS:
564 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
565 		f_dfu->dfu_status = DFU_STATUS_OK;
566 		/* no zlp? */
567 		value = RET_ZLP;
568 		break;
569 	default:
570 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
571 		value = RET_STALL;
572 		break;
573 	}
574 
575 	return value;
576 }
577 
578 static dfu_state_fn dfu_state[] = {
579 	state_app_idle,          /* DFU_STATE_appIDLE */
580 	state_app_detach,        /* DFU_STATE_appDETACH */
581 	state_dfu_idle,          /* DFU_STATE_dfuIDLE */
582 	state_dfu_dnload_sync,   /* DFU_STATE_dfuDNLOAD_SYNC */
583 	state_dfu_dnbusy,        /* DFU_STATE_dfuDNBUSY */
584 	state_dfu_dnload_idle,   /* DFU_STATE_dfuDNLOAD_IDLE */
585 	state_dfu_manifest_sync, /* DFU_STATE_dfuMANIFEST_SYNC */
586 	state_dfu_manifest,	 /* DFU_STATE_dfuMANIFEST */
587 	NULL,                    /* DFU_STATE_dfuMANIFEST_WAIT_RST */
588 	state_dfu_upload_idle,   /* DFU_STATE_dfuUPLOAD_IDLE */
589 	state_dfu_error          /* DFU_STATE_dfuERROR */
590 };
591 
592 static int
593 dfu_handle(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
594 {
595 	struct usb_gadget *gadget = f->config->cdev->gadget;
596 	struct usb_request *req = f->config->cdev->req;
597 	struct f_dfu *f_dfu = f->config->cdev->req->context;
598 	u16 len = le16_to_cpu(ctrl->wLength);
599 	u16 w_value = le16_to_cpu(ctrl->wValue);
600 	int value = 0;
601 	u8 req_type = ctrl->bRequestType & USB_TYPE_MASK;
602 
603 	debug("w_value: 0x%x len: 0x%x\n", w_value, len);
604 	debug("req_type: 0x%x ctrl->bRequest: 0x%x f_dfu->dfu_state: 0x%x\n",
605 	       req_type, ctrl->bRequest, f_dfu->dfu_state);
606 
607 	if (req_type == USB_TYPE_STANDARD) {
608 		if (ctrl->bRequest == USB_REQ_GET_DESCRIPTOR &&
609 		    (w_value >> 8) == DFU_DT_FUNC) {
610 			value = min(len, (u16) sizeof(dfu_func));
611 			memcpy(req->buf, &dfu_func, value);
612 		}
613 	} else /* DFU specific request */
614 		value = dfu_state[f_dfu->dfu_state] (f_dfu, ctrl, gadget, req);
615 
616 	if (value >= 0) {
617 		req->length = value;
618 		req->zero = value < len;
619 		value = usb_ep_queue(gadget->ep0, req, 0);
620 		if (value < 0) {
621 			debug("ep_queue --> %d\n", value);
622 			req->status = 0;
623 		}
624 	}
625 
626 	return value;
627 }
628 
629 /*-------------------------------------------------------------------------*/
630 
631 static int
632 dfu_prepare_strings(struct f_dfu *f_dfu, int n)
633 {
634 	struct dfu_entity *de = NULL;
635 	int i = 0;
636 
637 	f_dfu->strings = calloc(sizeof(struct usb_string), n + 1);
638 	if (!f_dfu->strings)
639 		return -ENOMEM;
640 
641 	for (i = 0; i < n; ++i) {
642 		de = dfu_get_entity(i);
643 		f_dfu->strings[i].s = de->name;
644 	}
645 
646 	f_dfu->strings[i].id = 0;
647 	f_dfu->strings[i].s = NULL;
648 
649 	return 0;
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 	f_dfu->dfu_state = DFU_STATE_dfuIDLE;
765 	f_dfu->dfu_status = DFU_STATUS_OK;
766 
767 	return 0;
768 }
769 
770 static int __dfu_get_alt(struct usb_function *f, unsigned intf)
771 {
772 	struct f_dfu *f_dfu = func_to_dfu(f);
773 
774 	return f_dfu->altsetting;
775 }
776 
777 /* TODO: is this really what we need here? */
778 static void dfu_disable(struct usb_function *f)
779 {
780 	struct f_dfu *f_dfu = func_to_dfu(f);
781 	if (f_dfu->config == 0)
782 		return;
783 
784 	debug("%s: reset config\n", __func__);
785 
786 	f_dfu->config = 0;
787 }
788 
789 static int dfu_bind_config(struct usb_configuration *c)
790 {
791 	struct f_dfu *f_dfu;
792 	int status;
793 
794 	f_dfu = calloc(sizeof(*f_dfu), 1);
795 	if (!f_dfu)
796 		return -ENOMEM;
797 	f_dfu->usb_function.name = "dfu";
798 	f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
799 	f_dfu->usb_function.descriptors = dfu_runtime_descs;
800 	f_dfu->usb_function.bind = dfu_bind;
801 	f_dfu->usb_function.unbind = dfu_unbind;
802 	f_dfu->usb_function.set_alt = dfu_set_alt;
803 	f_dfu->usb_function.get_alt = __dfu_get_alt;
804 	f_dfu->usb_function.disable = dfu_disable;
805 	f_dfu->usb_function.strings = dfu_generic_strings;
806 	f_dfu->usb_function.setup = dfu_handle;
807 	f_dfu->poll_timeout = DFU_DEFAULT_POLL_TIMEOUT;
808 
809 	status = usb_add_function(c, &f_dfu->usb_function);
810 	if (status)
811 		free(f_dfu);
812 
813 	return status;
814 }
815 
816 int dfu_add(struct usb_configuration *c)
817 {
818 	int id;
819 
820 	id = usb_string_id(c->cdev);
821 	if (id < 0)
822 		return id;
823 	strings_dfu_generic[0].id = id;
824 	dfu_intf_runtime.iInterface = id;
825 
826 	debug("%s: cdev: 0x%p gadget:0x%p gadget->ep0: 0x%p\n", __func__,
827 	       c->cdev, c->cdev->gadget, c->cdev->gadget->ep0);
828 
829 	return dfu_bind_config(c);
830 }
831 
832 DECLARE_GADGET_BIND_CALLBACK(usb_dnl_dfu, dfu_add);
833