xref: /openbmc/u-boot/drivers/usb/gadget/f_dfu.c (revision c4f80f50)
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 typedef int (*dfu_state_fn) (struct f_dfu *,
48 			     const struct usb_ctrlrequest *,
49 			     struct usb_gadget *,
50 			     struct usb_request *);
51 
52 static inline struct f_dfu *func_to_dfu(struct usb_function *f)
53 {
54 	return container_of(f, struct f_dfu, usb_function);
55 }
56 
57 static const struct dfu_function_descriptor dfu_func = {
58 	.bLength =		sizeof dfu_func,
59 	.bDescriptorType =	DFU_DT_FUNC,
60 	.bmAttributes =		DFU_BIT_WILL_DETACH |
61 				DFU_BIT_MANIFESTATION_TOLERANT |
62 				DFU_BIT_CAN_UPLOAD |
63 				DFU_BIT_CAN_DNLOAD,
64 	.wDetachTimeOut =	0,
65 	.wTransferSize =	DFU_USB_BUFSIZ,
66 	.bcdDFUVersion =	__constant_cpu_to_le16(0x0110),
67 };
68 
69 static struct usb_interface_descriptor dfu_intf_runtime = {
70 	.bLength =		sizeof dfu_intf_runtime,
71 	.bDescriptorType =	USB_DT_INTERFACE,
72 	.bNumEndpoints =	0,
73 	.bInterfaceClass =	USB_CLASS_APP_SPEC,
74 	.bInterfaceSubClass =	1,
75 	.bInterfaceProtocol =	1,
76 	/* .iInterface = DYNAMIC */
77 };
78 
79 static struct usb_descriptor_header *dfu_runtime_descs[] = {
80 	(struct usb_descriptor_header *) &dfu_intf_runtime,
81 	NULL,
82 };
83 
84 static const struct usb_qualifier_descriptor dev_qualifier = {
85 	.bLength =		sizeof dev_qualifier,
86 	.bDescriptorType =	USB_DT_DEVICE_QUALIFIER,
87 	.bcdUSB =		__constant_cpu_to_le16(0x0200),
88 	.bDeviceClass =		USB_CLASS_VENDOR_SPEC,
89 	.bNumConfigurations =	1,
90 };
91 
92 static const char dfu_name[] = "Device Firmware Upgrade";
93 
94 /*
95  * static strings, in UTF-8
96  *
97  * dfu_generic configuration
98  */
99 static struct usb_string strings_dfu_generic[] = {
100 	[0].s = dfu_name,
101 	{  }			/* end of list */
102 };
103 
104 static struct usb_gadget_strings stringtab_dfu_generic = {
105 	.language	= 0x0409,	/* en-us */
106 	.strings	= strings_dfu_generic,
107 };
108 
109 static struct usb_gadget_strings *dfu_generic_strings[] = {
110 	&stringtab_dfu_generic,
111 	NULL,
112 };
113 
114 /*
115  * usb_function specific
116  */
117 static struct usb_gadget_strings stringtab_dfu = {
118 	.language	= 0x0409,	/* en-us */
119 	/*
120 	 * .strings
121 	 *
122 	 * assigned during initialization,
123 	 * depends on number of flash entities
124 	 *
125 	 */
126 };
127 
128 static struct usb_gadget_strings *dfu_strings[] = {
129 	&stringtab_dfu,
130 	NULL,
131 };
132 
133 static void dfu_set_poll_timeout(struct dfu_status *dstat, unsigned int ms)
134 {
135 	/*
136 	 * The bwPollTimeout DFU_GETSTATUS request payload provides information
137 	 * about minimum time, in milliseconds, that the host should wait before
138 	 * sending a subsequent DFU_GETSTATUS request
139 	 *
140 	 * This permits the device to vary the delay depending on its need to
141 	 * erase or program the memory
142 	 *
143 	 */
144 
145 	unsigned char *p = (unsigned char *)&ms;
146 
147 	if (!ms || (ms & ~DFU_POLL_TIMEOUT_MASK)) {
148 		dstat->bwPollTimeout[0] = 0;
149 		dstat->bwPollTimeout[1] = 0;
150 		dstat->bwPollTimeout[2] = 0;
151 
152 		return;
153 	}
154 
155 	dstat->bwPollTimeout[0] = *p++;
156 	dstat->bwPollTimeout[1] = *p++;
157 	dstat->bwPollTimeout[2] = *p;
158 }
159 
160 /*-------------------------------------------------------------------------*/
161 
162 static void dnload_request_complete(struct usb_ep *ep, struct usb_request *req)
163 {
164 	struct f_dfu *f_dfu = req->context;
165 
166 	dfu_write(dfu_get_entity(f_dfu->altsetting), req->buf,
167 		  req->length, f_dfu->blk_seq_num);
168 }
169 
170 static void dnload_request_flush(struct usb_ep *ep, struct usb_request *req)
171 {
172 	struct f_dfu *f_dfu = req->context;
173 
174 	dfu_flush(dfu_get_entity(f_dfu->altsetting), req->buf,
175 		  req->length, f_dfu->blk_seq_num);
176 }
177 
178 static inline int dfu_get_manifest_timeout(struct dfu_entity *dfu)
179 {
180 	return dfu->poll_timeout ? dfu->poll_timeout(dfu) :
181 		DFU_MANIFEST_POLL_TIMEOUT;
182 }
183 
184 static void handle_getstatus(struct usb_request *req)
185 {
186 	struct dfu_status *dstat = (struct dfu_status *)req->buf;
187 	struct f_dfu *f_dfu = req->context;
188 	struct dfu_entity *dfu = dfu_get_entity(f_dfu->altsetting);
189 
190 	dfu_set_poll_timeout(dstat, 0);
191 
192 	switch (f_dfu->dfu_state) {
193 	case DFU_STATE_dfuDNLOAD_SYNC:
194 	case DFU_STATE_dfuDNBUSY:
195 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_IDLE;
196 		break;
197 	case DFU_STATE_dfuMANIFEST_SYNC:
198 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST;
199 		break;
200 	case DFU_STATE_dfuMANIFEST:
201 		dfu_set_poll_timeout(dstat, dfu_get_manifest_timeout(dfu));
202 		break;
203 	default:
204 		break;
205 	}
206 
207 	if (f_dfu->poll_timeout)
208 		if (!(f_dfu->blk_seq_num %
209 		      (dfu_get_buf_size() / DFU_USB_BUFSIZ)))
210 			dfu_set_poll_timeout(dstat, f_dfu->poll_timeout);
211 
212 	/* send status response */
213 	dstat->bStatus = f_dfu->dfu_status;
214 	dstat->bState = f_dfu->dfu_state;
215 	dstat->iString = 0;
216 }
217 
218 static void handle_getstate(struct usb_request *req)
219 {
220 	struct f_dfu *f_dfu = req->context;
221 
222 	((u8 *)req->buf)[0] = f_dfu->dfu_state;
223 	req->actual = sizeof(u8);
224 }
225 
226 static inline void to_dfu_mode(struct f_dfu *f_dfu)
227 {
228 	f_dfu->usb_function.strings = dfu_strings;
229 	f_dfu->usb_function.hs_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 }
238 
239 static int handle_upload(struct usb_request *req, u16 len)
240 {
241 	struct f_dfu *f_dfu = req->context;
242 
243 	return dfu_read(dfu_get_entity(f_dfu->altsetting), req->buf,
244 			req->length, f_dfu->blk_seq_num);
245 }
246 
247 static int handle_dnload(struct usb_gadget *gadget, u16 len)
248 {
249 	struct usb_composite_dev *cdev = get_gadget_data(gadget);
250 	struct usb_request *req = cdev->req;
251 	struct f_dfu *f_dfu = req->context;
252 
253 	if (len == 0)
254 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST_SYNC;
255 
256 	req->complete = dnload_request_complete;
257 
258 	return len;
259 }
260 
261 /*-------------------------------------------------------------------------*/
262 /* DFU state machine  */
263 static int state_app_idle(struct f_dfu *f_dfu,
264 			  const struct usb_ctrlrequest *ctrl,
265 			  struct usb_gadget *gadget,
266 			  struct usb_request *req)
267 {
268 	int value = 0;
269 
270 	switch (ctrl->bRequest) {
271 	case USB_REQ_DFU_GETSTATUS:
272 		handle_getstatus(req);
273 		value = RET_STAT_LEN;
274 		break;
275 	case USB_REQ_DFU_GETSTATE:
276 		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 		handle_getstatus(req);
301 		value = RET_STAT_LEN;
302 		break;
303 	case USB_REQ_DFU_GETSTATE:
304 		handle_getstate(req);
305 		break;
306 	default:
307 		f_dfu->dfu_state = DFU_STATE_appIDLE;
308 		value = RET_STALL;
309 		break;
310 	}
311 
312 	return value;
313 }
314 
315 static int state_dfu_idle(struct f_dfu *f_dfu,
316 			  const struct usb_ctrlrequest *ctrl,
317 			  struct usb_gadget *gadget,
318 			  struct usb_request *req)
319 {
320 	u16 w_value = le16_to_cpu(ctrl->wValue);
321 	u16 len = le16_to_cpu(ctrl->wLength);
322 	int value = 0;
323 
324 	switch (ctrl->bRequest) {
325 	case USB_REQ_DFU_DNLOAD:
326 		if (len == 0) {
327 			f_dfu->dfu_state = DFU_STATE_dfuERROR;
328 			value = RET_STALL;
329 			break;
330 		}
331 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
332 		f_dfu->blk_seq_num = w_value;
333 		value = handle_dnload(gadget, len);
334 		break;
335 	case USB_REQ_DFU_UPLOAD:
336 		f_dfu->dfu_state = DFU_STATE_dfuUPLOAD_IDLE;
337 		f_dfu->blk_seq_num = 0;
338 		value = handle_upload(req, len);
339 		break;
340 	case USB_REQ_DFU_ABORT:
341 		/* no zlp? */
342 		value = RET_ZLP;
343 		break;
344 	case USB_REQ_DFU_GETSTATUS:
345 		handle_getstatus(req);
346 		value = RET_STAT_LEN;
347 		break;
348 	case USB_REQ_DFU_GETSTATE:
349 		handle_getstate(req);
350 		break;
351 	case USB_REQ_DFU_DETACH:
352 		/*
353 		 * Proprietary extension: 'detach' from idle mode and
354 		 * get back to runtime mode in case of USB Reset.  As
355 		 * much as I dislike this, we just can't use every USB
356 		 * bus reset to switch back to runtime mode, since at
357 		 * least the Linux USB stack likes to send a number of
358 		 * resets in a row :(
359 		 */
360 		f_dfu->dfu_state =
361 			DFU_STATE_dfuMANIFEST_WAIT_RST;
362 		to_runtime_mode(f_dfu);
363 		f_dfu->dfu_state = DFU_STATE_appIDLE;
364 
365 		dfu_trigger_reset();
366 		break;
367 	default:
368 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
369 		value = RET_STALL;
370 		break;
371 	}
372 
373 	return value;
374 }
375 
376 static int state_dfu_dnload_sync(struct f_dfu *f_dfu,
377 				 const struct usb_ctrlrequest *ctrl,
378 				 struct usb_gadget *gadget,
379 				 struct usb_request *req)
380 {
381 	int value = 0;
382 
383 	switch (ctrl->bRequest) {
384 	case USB_REQ_DFU_GETSTATUS:
385 		handle_getstatus(req);
386 		value = RET_STAT_LEN;
387 		break;
388 	case USB_REQ_DFU_GETSTATE:
389 		handle_getstate(req);
390 		break;
391 	default:
392 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
393 		value = RET_STALL;
394 		break;
395 	}
396 
397 	return value;
398 }
399 
400 static int state_dfu_dnbusy(struct f_dfu *f_dfu,
401 			    const struct usb_ctrlrequest *ctrl,
402 			    struct usb_gadget *gadget,
403 			    struct usb_request *req)
404 {
405 	int value = 0;
406 
407 	switch (ctrl->bRequest) {
408 	case USB_REQ_DFU_GETSTATUS:
409 		handle_getstatus(req);
410 		value = RET_STAT_LEN;
411 		break;
412 	default:
413 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
414 		value = RET_STALL;
415 		break;
416 	}
417 
418 	return value;
419 }
420 
421 static int state_dfu_dnload_idle(struct f_dfu *f_dfu,
422 				 const struct usb_ctrlrequest *ctrl,
423 				 struct usb_gadget *gadget,
424 				 struct usb_request *req)
425 {
426 	u16 w_value = le16_to_cpu(ctrl->wValue);
427 	u16 len = le16_to_cpu(ctrl->wLength);
428 	int value = 0;
429 
430 	switch (ctrl->bRequest) {
431 	case USB_REQ_DFU_DNLOAD:
432 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
433 		f_dfu->blk_seq_num = w_value;
434 		value = handle_dnload(gadget, len);
435 		break;
436 	case USB_REQ_DFU_ABORT:
437 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
438 		value = RET_ZLP;
439 		break;
440 	case USB_REQ_DFU_GETSTATUS:
441 		handle_getstatus(req);
442 		value = RET_STAT_LEN;
443 		break;
444 	case USB_REQ_DFU_GETSTATE:
445 		handle_getstate(req);
446 		break;
447 	default:
448 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
449 		value = RET_STALL;
450 		break;
451 	}
452 
453 	return value;
454 }
455 
456 static int state_dfu_manifest_sync(struct f_dfu *f_dfu,
457 				   const struct usb_ctrlrequest *ctrl,
458 				   struct usb_gadget *gadget,
459 				   struct usb_request *req)
460 {
461 	int value = 0;
462 
463 	switch (ctrl->bRequest) {
464 	case USB_REQ_DFU_GETSTATUS:
465 		/* We're MainfestationTolerant */
466 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST;
467 		handle_getstatus(req);
468 		f_dfu->blk_seq_num = 0;
469 		value = RET_STAT_LEN;
470 		req->complete = dnload_request_flush;
471 		break;
472 	case USB_REQ_DFU_GETSTATE:
473 		handle_getstate(req);
474 		break;
475 	default:
476 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
477 		value = RET_STALL;
478 		break;
479 	}
480 
481 	return value;
482 }
483 
484 static int state_dfu_manifest(struct f_dfu *f_dfu,
485 			      const struct usb_ctrlrequest *ctrl,
486 			      struct usb_gadget *gadget,
487 			      struct usb_request *req)
488 {
489 	int value = 0;
490 
491 	switch (ctrl->bRequest) {
492 	case USB_REQ_DFU_GETSTATUS:
493 		/* We're MainfestationTolerant */
494 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
495 		handle_getstatus(req);
496 		f_dfu->blk_seq_num = 0;
497 		value = RET_STAT_LEN;
498 		puts("DOWNLOAD ... OK\nCtrl+C to exit ...\n");
499 		break;
500 	case USB_REQ_DFU_GETSTATE:
501 		handle_getstate(req);
502 		break;
503 	default:
504 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
505 		value = RET_STALL;
506 		break;
507 	}
508 	return value;
509 }
510 
511 static int state_dfu_upload_idle(struct f_dfu *f_dfu,
512 				 const struct usb_ctrlrequest *ctrl,
513 				 struct usb_gadget *gadget,
514 				 struct usb_request *req)
515 {
516 	u16 w_value = le16_to_cpu(ctrl->wValue);
517 	u16 len = le16_to_cpu(ctrl->wLength);
518 	int value = 0;
519 
520 	switch (ctrl->bRequest) {
521 	case USB_REQ_DFU_UPLOAD:
522 		/* state transition if less data then requested */
523 		f_dfu->blk_seq_num = w_value;
524 		value = handle_upload(req, len);
525 		if (value >= 0 && value < len)
526 			f_dfu->dfu_state = DFU_STATE_dfuIDLE;
527 		break;
528 	case USB_REQ_DFU_ABORT:
529 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
530 		/* no zlp? */
531 		value = RET_ZLP;
532 		break;
533 	case USB_REQ_DFU_GETSTATUS:
534 		handle_getstatus(req);
535 		value = RET_STAT_LEN;
536 		break;
537 	case USB_REQ_DFU_GETSTATE:
538 		handle_getstate(req);
539 		break;
540 	default:
541 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
542 		value = RET_STALL;
543 		break;
544 	}
545 
546 	return value;
547 }
548 
549 static int state_dfu_error(struct f_dfu *f_dfu,
550 				 const struct usb_ctrlrequest *ctrl,
551 				 struct usb_gadget *gadget,
552 				 struct usb_request *req)
553 {
554 	int value = 0;
555 
556 	switch (ctrl->bRequest) {
557 	case USB_REQ_DFU_GETSTATUS:
558 		handle_getstatus(req);
559 		value = RET_STAT_LEN;
560 		break;
561 	case USB_REQ_DFU_GETSTATE:
562 		handle_getstate(req);
563 		break;
564 	case USB_REQ_DFU_CLRSTATUS:
565 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
566 		f_dfu->dfu_status = DFU_STATUS_OK;
567 		/* no zlp? */
568 		value = RET_ZLP;
569 		break;
570 	default:
571 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
572 		value = RET_STALL;
573 		break;
574 	}
575 
576 	return value;
577 }
578 
579 static dfu_state_fn dfu_state[] = {
580 	state_app_idle,          /* DFU_STATE_appIDLE */
581 	state_app_detach,        /* DFU_STATE_appDETACH */
582 	state_dfu_idle,          /* DFU_STATE_dfuIDLE */
583 	state_dfu_dnload_sync,   /* DFU_STATE_dfuDNLOAD_SYNC */
584 	state_dfu_dnbusy,        /* DFU_STATE_dfuDNBUSY */
585 	state_dfu_dnload_idle,   /* DFU_STATE_dfuDNLOAD_IDLE */
586 	state_dfu_manifest_sync, /* DFU_STATE_dfuMANIFEST_SYNC */
587 	state_dfu_manifest,	 /* DFU_STATE_dfuMANIFEST */
588 	NULL,                    /* DFU_STATE_dfuMANIFEST_WAIT_RST */
589 	state_dfu_upload_idle,   /* DFU_STATE_dfuUPLOAD_IDLE */
590 	state_dfu_error          /* DFU_STATE_dfuERROR */
591 };
592 
593 static int
594 dfu_handle(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
595 {
596 	struct usb_gadget *gadget = f->config->cdev->gadget;
597 	struct usb_request *req = f->config->cdev->req;
598 	struct f_dfu *f_dfu = f->config->cdev->req->context;
599 	u16 len = le16_to_cpu(ctrl->wLength);
600 	u16 w_value = le16_to_cpu(ctrl->wValue);
601 	int value = 0;
602 	u8 req_type = ctrl->bRequestType & USB_TYPE_MASK;
603 
604 	debug("w_value: 0x%x len: 0x%x\n", w_value, len);
605 	debug("req_type: 0x%x ctrl->bRequest: 0x%x f_dfu->dfu_state: 0x%x\n",
606 	       req_type, ctrl->bRequest, f_dfu->dfu_state);
607 
608 	if (req_type == USB_TYPE_STANDARD) {
609 		if (ctrl->bRequest == USB_REQ_GET_DESCRIPTOR &&
610 		    (w_value >> 8) == DFU_DT_FUNC) {
611 			value = min(len, (u16) sizeof(dfu_func));
612 			memcpy(req->buf, &dfu_func, value);
613 		}
614 	} else /* DFU specific request */
615 		value = dfu_state[f_dfu->dfu_state] (f_dfu, ctrl, gadget, req);
616 
617 	if (value >= 0) {
618 		req->length = value;
619 		req->zero = value < len;
620 		value = usb_ep_queue(gadget->ep0, req, 0);
621 		if (value < 0) {
622 			debug("ep_queue --> %d\n", value);
623 			req->status = 0;
624 		}
625 	}
626 
627 	return value;
628 }
629 
630 /*-------------------------------------------------------------------------*/
631 
632 static int
633 dfu_prepare_strings(struct f_dfu *f_dfu, int n)
634 {
635 	struct dfu_entity *de = NULL;
636 	int i = 0;
637 
638 	f_dfu->strings = calloc(sizeof(struct usb_string), n + 1);
639 	if (!f_dfu->strings)
640 		goto enomem;
641 
642 	for (i = 0; i < n; ++i) {
643 		de = dfu_get_entity(i);
644 		f_dfu->strings[i].s = de->name;
645 	}
646 
647 	f_dfu->strings[i].id = 0;
648 	f_dfu->strings[i].s = NULL;
649 
650 	return 0;
651 
652 enomem:
653 	while (i)
654 		f_dfu->strings[--i].s = NULL;
655 
656 	free(f_dfu->strings);
657 
658 	return -ENOMEM;
659 }
660 
661 static int dfu_prepare_function(struct f_dfu *f_dfu, int n)
662 {
663 	struct usb_interface_descriptor *d;
664 	int i = 0;
665 
666 	f_dfu->function = calloc(sizeof(struct usb_descriptor_header *), n + 1);
667 	if (!f_dfu->function)
668 		goto enomem;
669 
670 	for (i = 0; i < n; ++i) {
671 		d = calloc(sizeof(*d), 1);
672 		if (!d)
673 			goto enomem;
674 
675 		d->bLength =		sizeof(*d);
676 		d->bDescriptorType =	USB_DT_INTERFACE;
677 		d->bAlternateSetting =	i;
678 		d->bNumEndpoints =	0;
679 		d->bInterfaceClass =	USB_CLASS_APP_SPEC;
680 		d->bInterfaceSubClass =	1;
681 		d->bInterfaceProtocol =	2;
682 
683 		f_dfu->function[i] = (struct usb_descriptor_header *)d;
684 	}
685 	f_dfu->function[i] = NULL;
686 
687 	return 0;
688 
689 enomem:
690 	while (i) {
691 		free(f_dfu->function[--i]);
692 		f_dfu->function[i] = NULL;
693 	}
694 	free(f_dfu->function);
695 
696 	return -ENOMEM;
697 }
698 
699 static int dfu_bind(struct usb_configuration *c, struct usb_function *f)
700 {
701 	struct usb_composite_dev *cdev = c->cdev;
702 	struct f_dfu *f_dfu = func_to_dfu(f);
703 	int alt_num = dfu_get_alt_number();
704 	int rv, id, i;
705 
706 	id = usb_interface_id(c, f);
707 	if (id < 0)
708 		return id;
709 	dfu_intf_runtime.bInterfaceNumber = id;
710 
711 	f_dfu->dfu_state = DFU_STATE_appIDLE;
712 	f_dfu->dfu_status = DFU_STATUS_OK;
713 
714 	rv = dfu_prepare_function(f_dfu, alt_num);
715 	if (rv)
716 		goto error;
717 
718 	rv = dfu_prepare_strings(f_dfu, alt_num);
719 	if (rv)
720 		goto error;
721 	for (i = 0; i < alt_num; i++) {
722 		id = usb_string_id(cdev);
723 		if (id < 0)
724 			return id;
725 		f_dfu->strings[i].id = id;
726 		((struct usb_interface_descriptor *)f_dfu->function[i])
727 			->iInterface = id;
728 	}
729 
730 	to_dfu_mode(f_dfu);
731 
732 	stringtab_dfu.strings = f_dfu->strings;
733 
734 	cdev->req->context = f_dfu;
735 
736 error:
737 	return rv;
738 }
739 
740 static void dfu_unbind(struct usb_configuration *c, struct usb_function *f)
741 {
742 	struct f_dfu *f_dfu = func_to_dfu(f);
743 	int alt_num = dfu_get_alt_number();
744 	int i;
745 
746 	if (f_dfu->strings) {
747 		i = alt_num;
748 		while (i)
749 			f_dfu->strings[--i].s = NULL;
750 
751 		free(f_dfu->strings);
752 	}
753 
754 	if (f_dfu->function) {
755 		i = alt_num;
756 		while (i) {
757 			free(f_dfu->function[--i]);
758 			f_dfu->function[i] = NULL;
759 		}
760 		free(f_dfu->function);
761 	}
762 
763 	free(f_dfu);
764 }
765 
766 static int dfu_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
767 {
768 	struct f_dfu *f_dfu = func_to_dfu(f);
769 
770 	debug("%s: intf:%d alt:%d\n", __func__, intf, alt);
771 
772 	f_dfu->altsetting = alt;
773 
774 	return 0;
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.bind = dfu_bind;
800 	f_dfu->usb_function.unbind = dfu_unbind;
801 	f_dfu->usb_function.set_alt = dfu_set_alt;
802 	f_dfu->usb_function.disable = dfu_disable;
803 	f_dfu->usb_function.strings = dfu_generic_strings;
804 	f_dfu->usb_function.setup = dfu_handle;
805 	f_dfu->poll_timeout = DFU_DEFAULT_POLL_TIMEOUT;
806 
807 	status = usb_add_function(c, &f_dfu->usb_function);
808 	if (status)
809 		free(f_dfu);
810 
811 	return status;
812 }
813 
814 int dfu_add(struct usb_configuration *c)
815 {
816 	int id;
817 
818 	id = usb_string_id(c->cdev);
819 	if (id < 0)
820 		return id;
821 	strings_dfu_generic[0].id = id;
822 	dfu_intf_runtime.iInterface = id;
823 
824 	debug("%s: cdev: 0x%p gadget:0x%p gadget->ep0: 0x%p\n", __func__,
825 	       c->cdev, c->cdev->gadget, c->cdev->gadget->ep0);
826 
827 	return dfu_bind_config(c);
828 }
829 
830 DECLARE_GADGET_BIND_CALLBACK(usb_dnl_dfu, dfu_add);
831