xref: /openbmc/u-boot/drivers/usb/gadget/f_dfu.c (revision 686e1448)
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  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21  */
22 
23 #include <errno.h>
24 #include <common.h>
25 #include <malloc.h>
26 
27 #include <linux/usb/ch9.h>
28 #include <linux/usb/gadget.h>
29 #include <linux/usb/composite.h>
30 
31 #include <dfu.h>
32 #include "f_dfu.h"
33 
34 struct f_dfu {
35 	struct usb_function		usb_function;
36 
37 	struct usb_descriptor_header	**function;
38 	struct usb_string		*strings;
39 
40 	/* when configured, we have one config */
41 	u8				config;
42 	u8				altsetting;
43 	enum dfu_state			dfu_state;
44 	unsigned int			dfu_status;
45 
46 	/* Send/received block number is handy for data integrity check */
47 	int                             blk_seq_num;
48 };
49 
50 typedef int (*dfu_state_fn) (struct f_dfu *,
51 			     const struct usb_ctrlrequest *,
52 			     struct usb_gadget *,
53 			     struct usb_request *);
54 
55 static inline struct f_dfu *func_to_dfu(struct usb_function *f)
56 {
57 	return container_of(f, struct f_dfu, usb_function);
58 }
59 
60 static const struct dfu_function_descriptor dfu_func = {
61 	.bLength =		sizeof dfu_func,
62 	.bDescriptorType =	DFU_DT_FUNC,
63 	.bmAttributes =		DFU_BIT_WILL_DETACH |
64 				DFU_BIT_MANIFESTATION_TOLERANT |
65 				DFU_BIT_CAN_UPLOAD |
66 				DFU_BIT_CAN_DNLOAD,
67 	.wDetachTimeOut =	0,
68 	.wTransferSize =	DFU_USB_BUFSIZ,
69 	.bcdDFUVersion =	__constant_cpu_to_le16(0x0110),
70 };
71 
72 static struct usb_interface_descriptor dfu_intf_runtime = {
73 	.bLength =		sizeof dfu_intf_runtime,
74 	.bDescriptorType =	USB_DT_INTERFACE,
75 	.bNumEndpoints =	0,
76 	.bInterfaceClass =	USB_CLASS_APP_SPEC,
77 	.bInterfaceSubClass =	1,
78 	.bInterfaceProtocol =	1,
79 	/* .iInterface = DYNAMIC */
80 };
81 
82 static struct usb_descriptor_header *dfu_runtime_descs[] = {
83 	(struct usb_descriptor_header *) &dfu_intf_runtime,
84 	NULL,
85 };
86 
87 static const struct usb_qualifier_descriptor dev_qualifier = {
88 	.bLength =		sizeof dev_qualifier,
89 	.bDescriptorType =	USB_DT_DEVICE_QUALIFIER,
90 	.bcdUSB =		__constant_cpu_to_le16(0x0200),
91 	.bDeviceClass =		USB_CLASS_VENDOR_SPEC,
92 	.bNumConfigurations =	1,
93 };
94 
95 static const char dfu_name[] = "Device Firmware Upgrade";
96 
97 /*
98  * static strings, in UTF-8
99  *
100  * dfu_generic configuration
101  */
102 static struct usb_string strings_dfu_generic[] = {
103 	[0].s = dfu_name,
104 	{  }			/* end of list */
105 };
106 
107 static struct usb_gadget_strings stringtab_dfu_generic = {
108 	.language	= 0x0409,	/* en-us */
109 	.strings	= strings_dfu_generic,
110 };
111 
112 static struct usb_gadget_strings *dfu_generic_strings[] = {
113 	&stringtab_dfu_generic,
114 	NULL,
115 };
116 
117 /*
118  * usb_function specific
119  */
120 static struct usb_gadget_strings stringtab_dfu = {
121 	.language	= 0x0409,	/* en-us */
122 	/*
123 	 * .strings
124 	 *
125 	 * assigned during initialization,
126 	 * depends on number of flash entities
127 	 *
128 	 */
129 };
130 
131 static struct usb_gadget_strings *dfu_strings[] = {
132 	&stringtab_dfu,
133 	NULL,
134 };
135 
136 /*-------------------------------------------------------------------------*/
137 
138 static void dnload_request_complete(struct usb_ep *ep, struct usb_request *req)
139 {
140 	struct f_dfu *f_dfu = req->context;
141 
142 	dfu_write(dfu_get_entity(f_dfu->altsetting), req->buf,
143 		  req->length, f_dfu->blk_seq_num);
144 
145 	if (req->length == 0)
146 		puts("DOWNLOAD ... OK\nCtrl+C to exit ...\n");
147 }
148 
149 static void handle_getstatus(struct usb_request *req)
150 {
151 	struct dfu_status *dstat = (struct dfu_status *)req->buf;
152 	struct f_dfu *f_dfu = req->context;
153 
154 	switch (f_dfu->dfu_state) {
155 	case DFU_STATE_dfuDNLOAD_SYNC:
156 	case DFU_STATE_dfuDNBUSY:
157 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_IDLE;
158 		break;
159 	case DFU_STATE_dfuMANIFEST_SYNC:
160 		break;
161 	default:
162 		break;
163 	}
164 
165 	/* send status response */
166 	dstat->bStatus = f_dfu->dfu_status;
167 	dstat->bwPollTimeout[0] = 0;
168 	dstat->bwPollTimeout[1] = 0;
169 	dstat->bwPollTimeout[2] = 0;
170 	dstat->bState = f_dfu->dfu_state;
171 	dstat->iString = 0;
172 }
173 
174 static void handle_getstate(struct usb_request *req)
175 {
176 	struct f_dfu *f_dfu = req->context;
177 
178 	((u8 *)req->buf)[0] = f_dfu->dfu_state;
179 	req->actual = sizeof(u8);
180 }
181 
182 static inline void to_dfu_mode(struct f_dfu *f_dfu)
183 {
184 	f_dfu->usb_function.strings = dfu_strings;
185 	f_dfu->usb_function.hs_descriptors = f_dfu->function;
186 }
187 
188 static inline void to_runtime_mode(struct f_dfu *f_dfu)
189 {
190 	f_dfu->usb_function.strings = NULL;
191 	f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
192 }
193 
194 static int handle_upload(struct usb_request *req, u16 len)
195 {
196 	struct f_dfu *f_dfu = req->context;
197 
198 	return dfu_read(dfu_get_entity(f_dfu->altsetting), req->buf,
199 			req->length, f_dfu->blk_seq_num);
200 }
201 
202 static int handle_dnload(struct usb_gadget *gadget, u16 len)
203 {
204 	struct usb_composite_dev *cdev = get_gadget_data(gadget);
205 	struct usb_request *req = cdev->req;
206 	struct f_dfu *f_dfu = req->context;
207 
208 	if (len == 0)
209 		f_dfu->dfu_state = DFU_STATE_dfuMANIFEST_SYNC;
210 
211 	req->complete = dnload_request_complete;
212 
213 	return len;
214 }
215 
216 /*-------------------------------------------------------------------------*/
217 /* DFU state machine  */
218 static int state_app_idle(struct f_dfu *f_dfu,
219 			  const struct usb_ctrlrequest *ctrl,
220 			  struct usb_gadget *gadget,
221 			  struct usb_request *req)
222 {
223 	int value = 0;
224 
225 	switch (ctrl->bRequest) {
226 	case USB_REQ_DFU_GETSTATUS:
227 		handle_getstatus(req);
228 		value = RET_STAT_LEN;
229 		break;
230 	case USB_REQ_DFU_GETSTATE:
231 		handle_getstate(req);
232 		break;
233 	case USB_REQ_DFU_DETACH:
234 		f_dfu->dfu_state = DFU_STATE_appDETACH;
235 		to_dfu_mode(f_dfu);
236 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
237 		value = RET_ZLP;
238 		break;
239 	default:
240 		value = RET_STALL;
241 		break;
242 	}
243 
244 	return value;
245 }
246 
247 static int state_app_detach(struct f_dfu *f_dfu,
248 			    const struct usb_ctrlrequest *ctrl,
249 			    struct usb_gadget *gadget,
250 			    struct usb_request *req)
251 {
252 	int value = 0;
253 
254 	switch (ctrl->bRequest) {
255 	case USB_REQ_DFU_GETSTATUS:
256 		handle_getstatus(req);
257 		value = RET_STAT_LEN;
258 		break;
259 	case USB_REQ_DFU_GETSTATE:
260 		handle_getstate(req);
261 		break;
262 	default:
263 		f_dfu->dfu_state = DFU_STATE_appIDLE;
264 		value = RET_STALL;
265 		break;
266 	}
267 
268 	return value;
269 }
270 
271 static int state_dfu_idle(struct f_dfu *f_dfu,
272 			  const struct usb_ctrlrequest *ctrl,
273 			  struct usb_gadget *gadget,
274 			  struct usb_request *req)
275 {
276 	u16 w_value = le16_to_cpu(ctrl->wValue);
277 	u16 len = le16_to_cpu(ctrl->wLength);
278 	int value = 0;
279 
280 	switch (ctrl->bRequest) {
281 	case USB_REQ_DFU_DNLOAD:
282 		if (len == 0) {
283 			f_dfu->dfu_state = DFU_STATE_dfuERROR;
284 			value = RET_STALL;
285 			break;
286 		}
287 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
288 		f_dfu->blk_seq_num = w_value;
289 		value = handle_dnload(gadget, len);
290 		break;
291 	case USB_REQ_DFU_UPLOAD:
292 		f_dfu->dfu_state = DFU_STATE_dfuUPLOAD_IDLE;
293 		f_dfu->blk_seq_num = 0;
294 		value = handle_upload(req, len);
295 		break;
296 	case USB_REQ_DFU_ABORT:
297 		/* no zlp? */
298 		value = RET_ZLP;
299 		break;
300 	case USB_REQ_DFU_GETSTATUS:
301 		handle_getstatus(req);
302 		value = RET_STAT_LEN;
303 		break;
304 	case USB_REQ_DFU_GETSTATE:
305 		handle_getstate(req);
306 		break;
307 	case USB_REQ_DFU_DETACH:
308 		/*
309 		 * Proprietary extension: 'detach' from idle mode and
310 		 * get back to runtime mode in case of USB Reset.  As
311 		 * much as I dislike this, we just can't use every USB
312 		 * bus reset to switch back to runtime mode, since at
313 		 * least the Linux USB stack likes to send a number of
314 		 * resets in a row :(
315 		 */
316 		f_dfu->dfu_state =
317 			DFU_STATE_dfuMANIFEST_WAIT_RST;
318 		to_runtime_mode(f_dfu);
319 		f_dfu->dfu_state = DFU_STATE_appIDLE;
320 		break;
321 	default:
322 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
323 		value = RET_STALL;
324 		break;
325 	}
326 
327 	return value;
328 }
329 
330 static int state_dfu_dnload_sync(struct f_dfu *f_dfu,
331 				 const struct usb_ctrlrequest *ctrl,
332 				 struct usb_gadget *gadget,
333 				 struct usb_request *req)
334 {
335 	int value = 0;
336 
337 	switch (ctrl->bRequest) {
338 	case USB_REQ_DFU_GETSTATUS:
339 		handle_getstatus(req);
340 		value = RET_STAT_LEN;
341 		break;
342 	case USB_REQ_DFU_GETSTATE:
343 		handle_getstate(req);
344 		break;
345 	default:
346 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
347 		value = RET_STALL;
348 		break;
349 	}
350 
351 	return value;
352 }
353 
354 static int state_dfu_dnbusy(struct f_dfu *f_dfu,
355 			    const struct usb_ctrlrequest *ctrl,
356 			    struct usb_gadget *gadget,
357 			    struct usb_request *req)
358 {
359 	int value = 0;
360 
361 	switch (ctrl->bRequest) {
362 	case USB_REQ_DFU_GETSTATUS:
363 		handle_getstatus(req);
364 		value = RET_STAT_LEN;
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_idle(struct f_dfu *f_dfu,
376 				 const struct usb_ctrlrequest *ctrl,
377 				 struct usb_gadget *gadget,
378 				 struct usb_request *req)
379 {
380 	u16 w_value = le16_to_cpu(ctrl->wValue);
381 	u16 len = le16_to_cpu(ctrl->wLength);
382 	int value = 0;
383 
384 	switch (ctrl->bRequest) {
385 	case USB_REQ_DFU_DNLOAD:
386 		f_dfu->dfu_state = DFU_STATE_dfuDNLOAD_SYNC;
387 		f_dfu->blk_seq_num = w_value;
388 		value = handle_dnload(gadget, len);
389 		break;
390 	case USB_REQ_DFU_ABORT:
391 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
392 		value = RET_ZLP;
393 		break;
394 	case USB_REQ_DFU_GETSTATUS:
395 		handle_getstatus(req);
396 		value = RET_STAT_LEN;
397 		break;
398 	case USB_REQ_DFU_GETSTATE:
399 		handle_getstate(req);
400 		break;
401 	default:
402 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
403 		value = RET_STALL;
404 		break;
405 	}
406 
407 	return value;
408 }
409 
410 static int state_dfu_manifest_sync(struct f_dfu *f_dfu,
411 				   const struct usb_ctrlrequest *ctrl,
412 				   struct usb_gadget *gadget,
413 				   struct usb_request *req)
414 {
415 	int value = 0;
416 
417 	switch (ctrl->bRequest) {
418 	case USB_REQ_DFU_GETSTATUS:
419 		/* We're MainfestationTolerant */
420 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
421 		handle_getstatus(req);
422 		f_dfu->blk_seq_num = 0;
423 		value = RET_STAT_LEN;
424 		break;
425 	case USB_REQ_DFU_GETSTATE:
426 		handle_getstate(req);
427 		break;
428 	default:
429 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
430 		value = RET_STALL;
431 		break;
432 	}
433 
434 	return value;
435 }
436 
437 static int state_dfu_upload_idle(struct f_dfu *f_dfu,
438 				 const struct usb_ctrlrequest *ctrl,
439 				 struct usb_gadget *gadget,
440 				 struct usb_request *req)
441 {
442 	u16 w_value = le16_to_cpu(ctrl->wValue);
443 	u16 len = le16_to_cpu(ctrl->wLength);
444 	int value = 0;
445 
446 	switch (ctrl->bRequest) {
447 	case USB_REQ_DFU_UPLOAD:
448 		/* state transition if less data then requested */
449 		f_dfu->blk_seq_num = w_value;
450 		value = handle_upload(req, len);
451 		if (value >= 0 && value < len)
452 			f_dfu->dfu_state = DFU_STATE_dfuIDLE;
453 		break;
454 	case USB_REQ_DFU_ABORT:
455 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
456 		/* no zlp? */
457 		value = RET_ZLP;
458 		break;
459 	case USB_REQ_DFU_GETSTATUS:
460 		handle_getstatus(req);
461 		value = RET_STAT_LEN;
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_error(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 		handle_getstatus(req);
485 		value = RET_STAT_LEN;
486 		break;
487 	case USB_REQ_DFU_GETSTATE:
488 		handle_getstate(req);
489 		break;
490 	case USB_REQ_DFU_CLRSTATUS:
491 		f_dfu->dfu_state = DFU_STATE_dfuIDLE;
492 		f_dfu->dfu_status = DFU_STATUS_OK;
493 		/* no zlp? */
494 		value = RET_ZLP;
495 		break;
496 	default:
497 		f_dfu->dfu_state = DFU_STATE_dfuERROR;
498 		value = RET_STALL;
499 		break;
500 	}
501 
502 	return value;
503 }
504 
505 static dfu_state_fn dfu_state[] = {
506 	state_app_idle,          /* DFU_STATE_appIDLE */
507 	state_app_detach,        /* DFU_STATE_appDETACH */
508 	state_dfu_idle,          /* DFU_STATE_dfuIDLE */
509 	state_dfu_dnload_sync,   /* DFU_STATE_dfuDNLOAD_SYNC */
510 	state_dfu_dnbusy,        /* DFU_STATE_dfuDNBUSY */
511 	state_dfu_dnload_idle,   /* DFU_STATE_dfuDNLOAD_IDLE */
512 	state_dfu_manifest_sync, /* DFU_STATE_dfuMANIFEST_SYNC */
513 	NULL,                    /* DFU_STATE_dfuMANIFEST */
514 	NULL,                    /* DFU_STATE_dfuMANIFEST_WAIT_RST */
515 	state_dfu_upload_idle,   /* DFU_STATE_dfuUPLOAD_IDLE */
516 	state_dfu_error          /* DFU_STATE_dfuERROR */
517 };
518 
519 static int
520 dfu_handle(struct usb_function *f, const struct usb_ctrlrequest *ctrl)
521 {
522 	struct usb_gadget *gadget = f->config->cdev->gadget;
523 	struct usb_request *req = f->config->cdev->req;
524 	struct f_dfu *f_dfu = f->config->cdev->req->context;
525 	u16 len = le16_to_cpu(ctrl->wLength);
526 	u16 w_value = le16_to_cpu(ctrl->wValue);
527 	int value = 0;
528 	u8 req_type = ctrl->bRequestType & USB_TYPE_MASK;
529 
530 	debug("w_value: 0x%x len: 0x%x\n", w_value, len);
531 	debug("req_type: 0x%x ctrl->bRequest: 0x%x f_dfu->dfu_state: 0x%x\n",
532 	       req_type, ctrl->bRequest, f_dfu->dfu_state);
533 
534 	if (req_type == USB_TYPE_STANDARD) {
535 		if (ctrl->bRequest == USB_REQ_GET_DESCRIPTOR &&
536 		    (w_value >> 8) == DFU_DT_FUNC) {
537 			value = min(len, (u16) sizeof(dfu_func));
538 			memcpy(req->buf, &dfu_func, value);
539 		}
540 	} else /* DFU specific request */
541 		value = dfu_state[f_dfu->dfu_state] (f_dfu, ctrl, gadget, req);
542 
543 	if (value >= 0) {
544 		req->length = value;
545 		req->zero = value < len;
546 		value = usb_ep_queue(gadget->ep0, req, 0);
547 		if (value < 0) {
548 			debug("ep_queue --> %d\n", value);
549 			req->status = 0;
550 		}
551 	}
552 
553 	return value;
554 }
555 
556 /*-------------------------------------------------------------------------*/
557 
558 static int
559 dfu_prepare_strings(struct f_dfu *f_dfu, int n)
560 {
561 	struct dfu_entity *de = NULL;
562 	int i = 0;
563 
564 	f_dfu->strings = calloc(sizeof(struct usb_string), n + 1);
565 	if (!f_dfu->strings)
566 		goto enomem;
567 
568 	for (i = 0; i < n; ++i) {
569 		de = dfu_get_entity(i);
570 		f_dfu->strings[i].s = de->name;
571 	}
572 
573 	f_dfu->strings[i].id = 0;
574 	f_dfu->strings[i].s = NULL;
575 
576 	return 0;
577 
578 enomem:
579 	while (i)
580 		f_dfu->strings[--i].s = NULL;
581 
582 	free(f_dfu->strings);
583 
584 	return -ENOMEM;
585 }
586 
587 static int dfu_prepare_function(struct f_dfu *f_dfu, int n)
588 {
589 	struct usb_interface_descriptor *d;
590 	int i = 0;
591 
592 	f_dfu->function = calloc(sizeof(struct usb_descriptor_header *), n);
593 	if (!f_dfu->function)
594 		goto enomem;
595 
596 	for (i = 0; i < n; ++i) {
597 		d = calloc(sizeof(*d), 1);
598 		if (!d)
599 			goto enomem;
600 
601 		d->bLength =		sizeof(*d);
602 		d->bDescriptorType =	USB_DT_INTERFACE;
603 		d->bAlternateSetting =	i;
604 		d->bNumEndpoints =	0;
605 		d->bInterfaceClass =	USB_CLASS_APP_SPEC;
606 		d->bInterfaceSubClass =	1;
607 		d->bInterfaceProtocol =	2;
608 
609 		f_dfu->function[i] = (struct usb_descriptor_header *)d;
610 	}
611 	f_dfu->function[i] = NULL;
612 
613 	return 0;
614 
615 enomem:
616 	while (i) {
617 		free(f_dfu->function[--i]);
618 		f_dfu->function[i] = NULL;
619 	}
620 	free(f_dfu->function);
621 
622 	return -ENOMEM;
623 }
624 
625 static int dfu_bind(struct usb_configuration *c, struct usb_function *f)
626 {
627 	struct usb_composite_dev *cdev = c->cdev;
628 	struct f_dfu *f_dfu = func_to_dfu(f);
629 	int alt_num = dfu_get_alt_number();
630 	int rv, id, i;
631 
632 	id = usb_interface_id(c, f);
633 	if (id < 0)
634 		return id;
635 	dfu_intf_runtime.bInterfaceNumber = id;
636 
637 	f_dfu->dfu_state = DFU_STATE_appIDLE;
638 	f_dfu->dfu_status = DFU_STATUS_OK;
639 
640 	rv = dfu_prepare_function(f_dfu, alt_num);
641 	if (rv)
642 		goto error;
643 
644 	rv = dfu_prepare_strings(f_dfu, alt_num);
645 	if (rv)
646 		goto error;
647 	for (i = 0; i < alt_num; i++) {
648 		id = usb_string_id(cdev);
649 		if (id < 0)
650 			return id;
651 		f_dfu->strings[i].id = id;
652 		((struct usb_interface_descriptor *)f_dfu->function[i])
653 			->iInterface = id;
654 	}
655 
656 	stringtab_dfu.strings = f_dfu->strings;
657 
658 	cdev->req->context = f_dfu;
659 
660 error:
661 	return rv;
662 }
663 
664 static void dfu_unbind(struct usb_configuration *c, struct usb_function *f)
665 {
666 	struct f_dfu *f_dfu = func_to_dfu(f);
667 	int alt_num = dfu_get_alt_number();
668 	int i;
669 
670 	if (f_dfu->strings) {
671 		i = alt_num;
672 		while (i)
673 			f_dfu->strings[--i].s = NULL;
674 
675 		free(f_dfu->strings);
676 	}
677 
678 	if (f_dfu->function) {
679 		i = alt_num;
680 		while (i) {
681 			free(f_dfu->function[--i]);
682 			f_dfu->function[i] = NULL;
683 		}
684 		free(f_dfu->function);
685 	}
686 
687 	free(f_dfu);
688 }
689 
690 static int dfu_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
691 {
692 	struct f_dfu *f_dfu = func_to_dfu(f);
693 
694 	debug("%s: intf:%d alt:%d\n", __func__, intf, alt);
695 
696 	f_dfu->altsetting = alt;
697 
698 	return 0;
699 }
700 
701 /* TODO: is this really what we need here? */
702 static void dfu_disable(struct usb_function *f)
703 {
704 	struct f_dfu *f_dfu = func_to_dfu(f);
705 	if (f_dfu->config == 0)
706 		return;
707 
708 	debug("%s: reset config\n", __func__);
709 
710 	f_dfu->config = 0;
711 }
712 
713 static int dfu_bind_config(struct usb_configuration *c)
714 {
715 	struct f_dfu *f_dfu;
716 	int status;
717 
718 	f_dfu = calloc(sizeof(*f_dfu), 1);
719 	if (!f_dfu)
720 		return -ENOMEM;
721 	f_dfu->usb_function.name = "dfu";
722 	f_dfu->usb_function.hs_descriptors = dfu_runtime_descs;
723 	f_dfu->usb_function.bind = dfu_bind;
724 	f_dfu->usb_function.unbind = dfu_unbind;
725 	f_dfu->usb_function.set_alt = dfu_set_alt;
726 	f_dfu->usb_function.disable = dfu_disable;
727 	f_dfu->usb_function.strings = dfu_generic_strings,
728 	f_dfu->usb_function.setup = dfu_handle,
729 
730 	status = usb_add_function(c, &f_dfu->usb_function);
731 	if (status)
732 		free(f_dfu);
733 
734 	return status;
735 }
736 
737 int dfu_add(struct usb_configuration *c)
738 {
739 	int id;
740 
741 	id = usb_string_id(c->cdev);
742 	if (id < 0)
743 		return id;
744 	strings_dfu_generic[0].id = id;
745 	dfu_intf_runtime.iInterface = id;
746 
747 	debug("%s: cdev: 0x%p gadget:0x%p gadget->ep0: 0x%p\n", __func__,
748 	       c->cdev, c->cdev->gadget, c->cdev->gadget->ep0);
749 
750 	return dfu_bind_config(c);
751 }
752