xref: /openbmc/u-boot/drivers/usb/gadget/f_dfu.c (revision 9d466f2f)
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->actual, 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 int 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 	return sizeof(struct dfu_status);
215 }
216 
217 static int handle_getstate(struct usb_request *req)
218 {
219 	struct f_dfu *f_dfu = req->context;
220 
221 	((u8 *)req->buf)[0] = f_dfu->dfu_state;
222 	return sizeof(u8);
223 }
224 
225 static inline void to_dfu_mode(struct f_dfu *f_dfu)
226 {
227 	f_dfu->usb_function.strings = dfu_strings;
228 	f_dfu->usb_function.hs_descriptors = f_dfu->function;
229 	f_dfu->usb_function.descriptors = f_dfu->function;
230 	f_dfu->dfu_state = DFU_STATE_dfuIDLE;
231 }
232 
233 static inline void to_runtime_mode(struct f_dfu *f_dfu)
234 {
235 	f_dfu->usb_function.strings = NULL;
236 	f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
237 	f_dfu->usb_function.descriptors = dfu_runtime_descs;
238 }
239 
240 static int handle_upload(struct usb_request *req, u16 len)
241 {
242 	struct f_dfu *f_dfu = req->context;
243 
244 	return dfu_read(dfu_get_entity(f_dfu->altsetting), req->buf,
245 			req->length, f_dfu->blk_seq_num);
246 }
247 
248 static int handle_dnload(struct usb_gadget *gadget, u16 len)
249 {
250 	struct usb_composite_dev *cdev = get_gadget_data(gadget);
251 	struct usb_request *req = cdev->req;
252 	struct f_dfu *f_dfu = req->context;
253 
254 	if (len == 0)
255 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST_SYNC;
256 
257 	req->complete = dnload_request_complete;
258 
259 	return len;
260 }
261 
262 /*-------------------------------------------------------------------------*/
263 /* DFU state machine  */
264 static int state_app_idle(struct f_dfu *f_dfu,
265 			  const struct usb_ctrlrequest *ctrl,
266 			  struct usb_gadget *gadget,
267 			  struct usb_request *req)
268 {
269 	int value = 0;
270 
271 	switch (ctrl->bRequest) {
272 	case USB_REQ_DFU_GETSTATUS:
273 		value = handle_getstatus(req);
274 		break;
275 	case USB_REQ_DFU_GETSTATE:
276 		value = handle_getstate(req);
277 		break;
278 	case USB_REQ_DFU_DETACH:
279 		f_dfu->dfu_state = DFU_STATE_appDETACH;
280 		to_dfu_mode(f_dfu);
281 		value = RET_ZLP;
282 		break;
283 	default:
284 		value = RET_STALL;
285 		break;
286 	}
287 
288 	return value;
289 }
290 
291 static int state_app_detach(struct f_dfu *f_dfu,
292 			    const struct usb_ctrlrequest *ctrl,
293 			    struct usb_gadget *gadget,
294 			    struct usb_request *req)
295 {
296 	int value = 0;
297 
298 	switch (ctrl->bRequest) {
299 	case USB_REQ_DFU_GETSTATUS:
300 		value = handle_getstatus(req);
301 		break;
302 	case USB_REQ_DFU_GETSTATE:
303 		value = 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 		value = handle_getstatus(req);
345 		break;
346 	case USB_REQ_DFU_GETSTATE:
347 		value = handle_getstate(req);
348 		break;
349 	case USB_REQ_DFU_DETACH:
350 		/*
351 		 * Proprietary extension: 'detach' from idle mode and
352 		 * get back to runtime mode in case of USB Reset.  As
353 		 * much as I dislike this, we just can't use every USB
354 		 * bus reset to switch back to runtime mode, since at
355 		 * least the Linux USB stack likes to send a number of
356 		 * resets in a row :(
357 		 */
358 		f_dfu->dfu_state =
359 			DFU_STATE_dfuMANIFEST_WAIT_RST;
360 		to_runtime_mode(f_dfu);
361 		f_dfu->dfu_state = DFU_STATE_appIDLE;
362 
363 		g_dnl_trigger_detach();
364 		break;
365 	default:
366 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
367 		value = RET_STALL;
368 		break;
369 	}
370 
371 	return value;
372 }
373 
374 static int state_dfu_dnload_sync(struct f_dfu *f_dfu,
375 				 const struct usb_ctrlrequest *ctrl,
376 				 struct usb_gadget *gadget,
377 				 struct usb_request *req)
378 {
379 	int value = 0;
380 
381 	switch (ctrl->bRequest) {
382 	case USB_REQ_DFU_GETSTATUS:
383 		value = handle_getstatus(req);
384 		break;
385 	case USB_REQ_DFU_GETSTATE:
386 		value = handle_getstate(req);
387 		break;
388 	default:
389 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
390 		value = RET_STALL;
391 		break;
392 	}
393 
394 	return value;
395 }
396 
397 static int state_dfu_dnbusy(struct f_dfu *f_dfu,
398 			    const struct usb_ctrlrequest *ctrl,
399 			    struct usb_gadget *gadget,
400 			    struct usb_request *req)
401 {
402 	int value = 0;
403 
404 	switch (ctrl->bRequest) {
405 	case USB_REQ_DFU_GETSTATUS:
406 		value = handle_getstatus(req);
407 		break;
408 	default:
409 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
410 		value = RET_STALL;
411 		break;
412 	}
413 
414 	return value;
415 }
416 
417 static int state_dfu_dnload_idle(struct f_dfu *f_dfu,
418 				 const struct usb_ctrlrequest *ctrl,
419 				 struct usb_gadget *gadget,
420 				 struct usb_request *req)
421 {
422 	u16 w_value = le16_to_cpu(ctrl->wValue);
423 	u16 len = le16_to_cpu(ctrl->wLength);
424 	int value = 0;
425 
426 	switch (ctrl->bRequest) {
427 	case USB_REQ_DFU_DNLOAD:
428 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
429 		f_dfu->blk_seq_num = w_value;
430 		value = handle_dnload(gadget, len);
431 		break;
432 	case USB_REQ_DFU_ABORT:
433 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
434 		value = RET_ZLP;
435 		break;
436 	case USB_REQ_DFU_GETSTATUS:
437 		value = handle_getstatus(req);
438 		break;
439 	case USB_REQ_DFU_GETSTATE:
440 		value = handle_getstate(req);
441 		break;
442 	default:
443 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
444 		value = RET_STALL;
445 		break;
446 	}
447 
448 	return value;
449 }
450 
451 static int state_dfu_manifest_sync(struct f_dfu *f_dfu,
452 				   const struct usb_ctrlrequest *ctrl,
453 				   struct usb_gadget *gadget,
454 				   struct usb_request *req)
455 {
456 	int value = 0;
457 
458 	switch (ctrl->bRequest) {
459 	case USB_REQ_DFU_GETSTATUS:
460 		/* We're MainfestationTolerant */
461 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST;
462 		value = handle_getstatus(req);
463 		f_dfu->blk_seq_num = 0;
464 		req->complete = dnload_request_flush;
465 		break;
466 	case USB_REQ_DFU_GETSTATE:
467 		value = handle_getstate(req);
468 		break;
469 	default:
470 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
471 		value = RET_STALL;
472 		break;
473 	}
474 
475 	return value;
476 }
477 
478 static int state_dfu_manifest(struct f_dfu *f_dfu,
479 			      const struct usb_ctrlrequest *ctrl,
480 			      struct usb_gadget *gadget,
481 			      struct usb_request *req)
482 {
483 	int value = 0;
484 
485 	switch (ctrl->bRequest) {
486 	case USB_REQ_DFU_GETSTATUS:
487 		/* We're MainfestationTolerant */
488 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
489 		value = handle_getstatus(req);
490 		f_dfu->blk_seq_num = 0;
491 		puts("DOWNLOAD ... OK\nCtrl+C to exit ...\n");
492 		break;
493 	case USB_REQ_DFU_GETSTATE:
494 		value = handle_getstate(req);
495 		break;
496 	default:
497 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
498 		value = RET_STALL;
499 		break;
500 	}
501 	return value;
502 }
503 
504 static int state_dfu_upload_idle(struct f_dfu *f_dfu,
505 				 const struct usb_ctrlrequest *ctrl,
506 				 struct usb_gadget *gadget,
507 				 struct usb_request *req)
508 {
509 	u16 w_value = le16_to_cpu(ctrl->wValue);
510 	u16 len = le16_to_cpu(ctrl->wLength);
511 	int value = 0;
512 
513 	switch (ctrl->bRequest) {
514 	case USB_REQ_DFU_UPLOAD:
515 		/* state transition if less data then requested */
516 		f_dfu->blk_seq_num = w_value;
517 		value = handle_upload(req, len);
518 		if (value >= 0 && value < len)
519 			f_dfu->dfu_state = DFU_STATE_dfuIDLE;
520 		break;
521 	case USB_REQ_DFU_ABORT:
522 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
523 		/* no zlp? */
524 		value = RET_ZLP;
525 		break;
526 	case USB_REQ_DFU_GETSTATUS:
527 		value = handle_getstatus(req);
528 		break;
529 	case USB_REQ_DFU_GETSTATE:
530 		value = handle_getstate(req);
531 		break;
532 	default:
533 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
534 		value = RET_STALL;
535 		break;
536 	}
537 
538 	return value;
539 }
540 
541 static int state_dfu_error(struct f_dfu *f_dfu,
542 				 const struct usb_ctrlrequest *ctrl,
543 				 struct usb_gadget *gadget,
544 				 struct usb_request *req)
545 {
546 	int value = 0;
547 
548 	switch (ctrl->bRequest) {
549 	case USB_REQ_DFU_GETSTATUS:
550 		value = handle_getstatus(req);
551 		break;
552 	case USB_REQ_DFU_GETSTATE:
553 		value = 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 		return -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 
644 static int dfu_prepare_function(struct f_dfu *f_dfu, int n)
645 {
646 	struct usb_interface_descriptor *d;
647 	int i = 0;
648 
649 	f_dfu->function = calloc(sizeof(struct usb_descriptor_header *), n + 2);
650 	if (!f_dfu->function)
651 		goto enomem;
652 
653 	for (i = 0; i < n; ++i) {
654 		d = calloc(sizeof(*d), 1);
655 		if (!d)
656 			goto enomem;
657 
658 		d->bLength =		sizeof(*d);
659 		d->bDescriptorType =	USB_DT_INTERFACE;
660 		d->bAlternateSetting =	i;
661 		d->bNumEndpoints =	0;
662 		d->bInterfaceClass =	USB_CLASS_APP_SPEC;
663 		d->bInterfaceSubClass =	1;
664 		d->bInterfaceProtocol =	2;
665 
666 		f_dfu->function[i] = (struct usb_descriptor_header *)d;
667 	}
668 
669 	/* add DFU Functional Descriptor */
670 	f_dfu->function[i] = calloc(sizeof(dfu_func), 1);
671 	if (!f_dfu->function[i])
672 		goto enomem;
673 	memcpy(f_dfu->function[i], &dfu_func, sizeof(dfu_func));
674 
675 	i++;
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 	const char *s;
695 	int alt_num = dfu_get_alt_number();
696 	int rv, id, i;
697 
698 	id = usb_interface_id(c, f);
699 	if (id < 0)
700 		return id;
701 	dfu_intf_runtime.bInterfaceNumber = id;
702 
703 	f_dfu->dfu_state = DFU_STATE_appIDLE;
704 	f_dfu->dfu_status = DFU_STATUS_OK;
705 
706 	rv = dfu_prepare_function(f_dfu, alt_num);
707 	if (rv)
708 		goto error;
709 
710 	rv = dfu_prepare_strings(f_dfu, alt_num);
711 	if (rv)
712 		goto error;
713 	for (i = 0; i < alt_num; i++) {
714 		id = usb_string_id(cdev);
715 		if (id < 0)
716 			return id;
717 		f_dfu->strings[i].id = id;
718 		((struct usb_interface_descriptor *)f_dfu->function[i])
719 			->iInterface = id;
720 	}
721 
722 	to_dfu_mode(f_dfu);
723 
724 	stringtab_dfu.strings = f_dfu->strings;
725 
726 	cdev->req->context = f_dfu;
727 
728 	s = env_get("serial#");
729 	if (s)
730 		g_dnl_set_serialnumber((char *)s);
731 
732 error:
733 	return rv;
734 }
735 
736 static void dfu_unbind(struct usb_configuration *c, struct usb_function *f)
737 {
738 	struct f_dfu *f_dfu = func_to_dfu(f);
739 	int alt_num = dfu_get_alt_number();
740 	int i;
741 
742 	if (f_dfu->strings) {
743 		i = alt_num;
744 		while (i)
745 			f_dfu->strings[--i].s = NULL;
746 
747 		free(f_dfu->strings);
748 	}
749 
750 	if (f_dfu->function) {
751 		i = alt_num;
752 		while (i) {
753 			free(f_dfu->function[--i]);
754 			f_dfu->function[i] = NULL;
755 		}
756 		free(f_dfu->function);
757 	}
758 
759 	free(f_dfu);
760 }
761 
762 static int dfu_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
763 {
764 	struct f_dfu *f_dfu = func_to_dfu(f);
765 
766 	debug("%s: intf:%d alt:%d\n", __func__, intf, alt);
767 
768 	f_dfu->altsetting = alt;
769 	f_dfu->dfu_state = DFU_STATE_dfuIDLE;
770 	f_dfu->dfu_status = DFU_STATUS_OK;
771 
772 	return 0;
773 }
774 
775 static int __dfu_get_alt(struct usb_function *f, unsigned intf)
776 {
777 	struct f_dfu *f_dfu = func_to_dfu(f);
778 
779 	return f_dfu->altsetting;
780 }
781 
782 /* TODO: is this really what we need here? */
783 static void dfu_disable(struct usb_function *f)
784 {
785 	struct f_dfu *f_dfu = func_to_dfu(f);
786 	if (f_dfu->config == 0)
787 		return;
788 
789 	debug("%s: reset config\n", __func__);
790 
791 	f_dfu->config = 0;
792 }
793 
794 static int dfu_bind_config(struct usb_configuration *c)
795 {
796 	struct f_dfu *f_dfu;
797 	int status;
798 
799 	f_dfu = calloc(sizeof(*f_dfu), 1);
800 	if (!f_dfu)
801 		return -ENOMEM;
802 	f_dfu->usb_function.name = "dfu";
803 	f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
804 	f_dfu->usb_function.descriptors = dfu_runtime_descs;
805 	f_dfu->usb_function.bind = dfu_bind;
806 	f_dfu->usb_function.unbind = dfu_unbind;
807 	f_dfu->usb_function.set_alt = dfu_set_alt;
808 	f_dfu->usb_function.get_alt = __dfu_get_alt;
809 	f_dfu->usb_function.disable = dfu_disable;
810 	f_dfu->usb_function.strings = dfu_generic_strings;
811 	f_dfu->usb_function.setup = dfu_handle;
812 	f_dfu->poll_timeout = DFU_DEFAULT_POLL_TIMEOUT;
813 
814 	status = usb_add_function(c, &f_dfu->usb_function);
815 	if (status)
816 		free(f_dfu);
817 
818 	return status;
819 }
820 
821 int dfu_add(struct usb_configuration *c)
822 {
823 	int id;
824 
825 	id = usb_string_id(c->cdev);
826 	if (id < 0)
827 		return id;
828 	strings_dfu_generic[0].id = id;
829 	dfu_intf_runtime.iInterface = id;
830 
831 	debug("%s: cdev: 0x%p gadget:0x%p gadget->ep0: 0x%p\n", __func__,
832 	       c->cdev, c->cdev->gadget, c->cdev->gadget->ep0);
833 
834 	return dfu_bind_config(c);
835 }
836 
837 DECLARE_GADGET_BIND_CALLBACK(usb_dnl_dfu, dfu_add);
838