xref: /openbmc/linux/tools/usb/ffs-test.c (revision be709d48)
1 /*
2  * ffs-test.c -- user mode filesystem api for usb composite function
3  *
4  * Copyright (C) 2010 Samsung Electronics
5  *                    Author: Michal Nazarewicz <mina86@mina86.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21 
22 /* $(CROSS_COMPILE)cc -Wall -Wextra -g -o ffs-test ffs-test.c -lpthread */
23 
24 
25 #define _DEFAULT_SOURCE /* for endian.h */
26 
27 #include <endian.h>
28 #include <errno.h>
29 #include <fcntl.h>
30 #include <pthread.h>
31 #include <stdarg.h>
32 #include <stdbool.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <sys/ioctl.h>
37 #include <sys/stat.h>
38 #include <sys/types.h>
39 #include <unistd.h>
40 #include <tools/le_byteshift.h>
41 
42 #include "../../include/uapi/linux/usb/functionfs.h"
43 
44 
45 /******************** Little Endian Handling ********************************/
46 
47 /*
48  * cpu_to_le16/32 are used when initializing structures, a context where a
49  * function call is not allowed. To solve this, we code cpu_to_le16/32 in a way
50  * that allows them to be used when initializing structures.
51  */
52 
53 #if __BYTE_ORDER == __LITTLE_ENDIAN
54 #define cpu_to_le16(x)  (x)
55 #define cpu_to_le32(x)  (x)
56 #else
57 #define cpu_to_le16(x)  ((((x) >> 8) & 0xffu) | (((x) & 0xffu) << 8))
58 #define cpu_to_le32(x)  \
59 	((((x) & 0xff000000u) >> 24) | (((x) & 0x00ff0000u) >>  8) | \
60 	(((x) & 0x0000ff00u) <<  8) | (((x) & 0x000000ffu) << 24))
61 #endif
62 
63 #define le32_to_cpu(x)  le32toh(x)
64 #define le16_to_cpu(x)  le16toh(x)
65 
66 /******************** Messages and Errors ***********************************/
67 
68 static const char argv0[] = "ffs-test";
69 
70 static unsigned verbosity = 7;
71 
72 static void _msg(unsigned level, const char *fmt, ...)
73 {
74 	if (level < 2)
75 		level = 2;
76 	else if (level > 7)
77 		level = 7;
78 
79 	if (level <= verbosity) {
80 		static const char levels[8][6] = {
81 			[2] = "crit:",
82 			[3] = "err: ",
83 			[4] = "warn:",
84 			[5] = "note:",
85 			[6] = "info:",
86 			[7] = "dbg: "
87 		};
88 
89 		int _errno = errno;
90 		va_list ap;
91 
92 		fprintf(stderr, "%s: %s ", argv0, levels[level]);
93 		va_start(ap, fmt);
94 		vfprintf(stderr, fmt, ap);
95 		va_end(ap);
96 
97 		if (fmt[strlen(fmt) - 1] != '\n') {
98 			char buffer[128];
99 			strerror_r(_errno, buffer, sizeof buffer);
100 			fprintf(stderr, ": (-%d) %s\n", _errno, buffer);
101 		}
102 
103 		fflush(stderr);
104 	}
105 }
106 
107 #define die(...)  (_msg(2, __VA_ARGS__), exit(1))
108 #define err(...)   _msg(3, __VA_ARGS__)
109 #define warn(...)  _msg(4, __VA_ARGS__)
110 #define note(...)  _msg(5, __VA_ARGS__)
111 #define info(...)  _msg(6, __VA_ARGS__)
112 #define debug(...) _msg(7, __VA_ARGS__)
113 
114 #define die_on(cond, ...) do { \
115 	if (cond) \
116 		die(__VA_ARGS__); \
117 	} while (0)
118 
119 
120 /******************** Descriptors and Strings *******************************/
121 
122 static const struct {
123 	struct usb_functionfs_descs_head_v2 header;
124 	__le32 fs_count;
125 	__le32 hs_count;
126 	__le32 ss_count;
127 	struct {
128 		struct usb_interface_descriptor intf;
129 		struct usb_endpoint_descriptor_no_audio sink;
130 		struct usb_endpoint_descriptor_no_audio source;
131 	} __attribute__((packed)) fs_descs, hs_descs;
132 	struct {
133 		struct usb_interface_descriptor intf;
134 		struct usb_endpoint_descriptor_no_audio sink;
135 		struct usb_ss_ep_comp_descriptor sink_comp;
136 		struct usb_endpoint_descriptor_no_audio source;
137 		struct usb_ss_ep_comp_descriptor source_comp;
138 	} ss_descs;
139 } __attribute__((packed)) descriptors = {
140 	.header = {
141 		.magic = cpu_to_le32(FUNCTIONFS_DESCRIPTORS_MAGIC_V2),
142 		.flags = cpu_to_le32(FUNCTIONFS_HAS_FS_DESC |
143 				     FUNCTIONFS_HAS_HS_DESC |
144 				     FUNCTIONFS_HAS_SS_DESC),
145 		.length = cpu_to_le32(sizeof descriptors),
146 	},
147 	.fs_count = cpu_to_le32(3),
148 	.fs_descs = {
149 		.intf = {
150 			.bLength = sizeof descriptors.fs_descs.intf,
151 			.bDescriptorType = USB_DT_INTERFACE,
152 			.bNumEndpoints = 2,
153 			.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
154 			.iInterface = 1,
155 		},
156 		.sink = {
157 			.bLength = sizeof descriptors.fs_descs.sink,
158 			.bDescriptorType = USB_DT_ENDPOINT,
159 			.bEndpointAddress = 1 | USB_DIR_IN,
160 			.bmAttributes = USB_ENDPOINT_XFER_BULK,
161 			/* .wMaxPacketSize = autoconfiguration (kernel) */
162 		},
163 		.source = {
164 			.bLength = sizeof descriptors.fs_descs.source,
165 			.bDescriptorType = USB_DT_ENDPOINT,
166 			.bEndpointAddress = 2 | USB_DIR_OUT,
167 			.bmAttributes = USB_ENDPOINT_XFER_BULK,
168 			/* .wMaxPacketSize = autoconfiguration (kernel) */
169 		},
170 	},
171 	.hs_count = cpu_to_le32(3),
172 	.hs_descs = {
173 		.intf = {
174 			.bLength = sizeof descriptors.fs_descs.intf,
175 			.bDescriptorType = USB_DT_INTERFACE,
176 			.bNumEndpoints = 2,
177 			.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
178 			.iInterface = 1,
179 		},
180 		.sink = {
181 			.bLength = sizeof descriptors.hs_descs.sink,
182 			.bDescriptorType = USB_DT_ENDPOINT,
183 			.bEndpointAddress = 1 | USB_DIR_IN,
184 			.bmAttributes = USB_ENDPOINT_XFER_BULK,
185 			.wMaxPacketSize = cpu_to_le16(512),
186 		},
187 		.source = {
188 			.bLength = sizeof descriptors.hs_descs.source,
189 			.bDescriptorType = USB_DT_ENDPOINT,
190 			.bEndpointAddress = 2 | USB_DIR_OUT,
191 			.bmAttributes = USB_ENDPOINT_XFER_BULK,
192 			.wMaxPacketSize = cpu_to_le16(512),
193 			.bInterval = 1, /* NAK every 1 uframe */
194 		},
195 	},
196 	.ss_count = cpu_to_le32(5),
197 	.ss_descs = {
198 		.intf = {
199 			.bLength = sizeof descriptors.fs_descs.intf,
200 			.bDescriptorType = USB_DT_INTERFACE,
201 			.bNumEndpoints = 2,
202 			.bInterfaceClass = USB_CLASS_VENDOR_SPEC,
203 			.iInterface = 1,
204 		},
205 		.sink = {
206 			.bLength = sizeof descriptors.hs_descs.sink,
207 			.bDescriptorType = USB_DT_ENDPOINT,
208 			.bEndpointAddress = 1 | USB_DIR_IN,
209 			.bmAttributes = USB_ENDPOINT_XFER_BULK,
210 			.wMaxPacketSize = cpu_to_le16(1024),
211 		},
212 		.sink_comp = {
213 			.bLength = USB_DT_SS_EP_COMP_SIZE,
214 			.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
215 			.bMaxBurst = 0,
216 			.bmAttributes = 0,
217 			.wBytesPerInterval = 0,
218 		},
219 		.source = {
220 			.bLength = sizeof descriptors.hs_descs.source,
221 			.bDescriptorType = USB_DT_ENDPOINT,
222 			.bEndpointAddress = 2 | USB_DIR_OUT,
223 			.bmAttributes = USB_ENDPOINT_XFER_BULK,
224 			.wMaxPacketSize = cpu_to_le16(1024),
225 			.bInterval = 1, /* NAK every 1 uframe */
226 		},
227 		.source_comp = {
228 			.bLength = USB_DT_SS_EP_COMP_SIZE,
229 			.bDescriptorType = USB_DT_SS_ENDPOINT_COMP,
230 			.bMaxBurst = 0,
231 			.bmAttributes = 0,
232 			.wBytesPerInterval = 0,
233 		},
234 	},
235 };
236 
237 static size_t descs_to_legacy(void **legacy, const void *descriptors_v2)
238 {
239 	const unsigned char *descs_end, *descs_start;
240 	__u32 length, fs_count = 0, hs_count = 0, count;
241 
242 	/* Read v2 header */
243 	{
244 		const struct {
245 			const struct usb_functionfs_descs_head_v2 header;
246 			const __le32 counts[];
247 		} __attribute__((packed)) *const in = descriptors_v2;
248 		const __le32 *counts = in->counts;
249 		__u32 flags;
250 
251 		if (le32_to_cpu(in->header.magic) !=
252 		    FUNCTIONFS_DESCRIPTORS_MAGIC_V2)
253 			return 0;
254 		length = le32_to_cpu(in->header.length);
255 		if (length <= sizeof in->header)
256 			return 0;
257 		length -= sizeof in->header;
258 		flags = le32_to_cpu(in->header.flags);
259 		if (flags & ~(FUNCTIONFS_HAS_FS_DESC | FUNCTIONFS_HAS_HS_DESC |
260 			      FUNCTIONFS_HAS_SS_DESC))
261 			return 0;
262 
263 #define GET_NEXT_COUNT_IF_FLAG(ret, flg) do {		\
264 			if (!(flags & (flg)))		\
265 				break;			\
266 			if (length < 4)			\
267 				return 0;		\
268 			ret = le32_to_cpu(*counts);	\
269 			length -= 4;			\
270 			++counts;			\
271 		} while (0)
272 
273 		GET_NEXT_COUNT_IF_FLAG(fs_count, FUNCTIONFS_HAS_FS_DESC);
274 		GET_NEXT_COUNT_IF_FLAG(hs_count, FUNCTIONFS_HAS_HS_DESC);
275 		GET_NEXT_COUNT_IF_FLAG(count, FUNCTIONFS_HAS_SS_DESC);
276 
277 		count = fs_count + hs_count;
278 		if (!count)
279 			return 0;
280 		descs_start = (const void *)counts;
281 
282 #undef GET_NEXT_COUNT_IF_FLAG
283 	}
284 
285 	/*
286 	 * Find the end of FS and HS USB descriptors.  SS descriptors
287 	 * are ignored since legacy format does not support them.
288 	 */
289 	descs_end = descs_start;
290 	do {
291 		if (length < *descs_end)
292 			return 0;
293 		length -= *descs_end;
294 		descs_end += *descs_end;
295 	} while (--count);
296 
297 	/* Allocate legacy descriptors and copy the data. */
298 	{
299 #pragma GCC diagnostic push
300 #pragma GCC diagnostic ignored "-Wdeprecated-declarations"
301 		struct {
302 			struct usb_functionfs_descs_head header;
303 			__u8 descriptors[];
304 		} __attribute__((packed)) *out;
305 #pragma GCC diagnostic pop
306 
307 		length = sizeof out->header + (descs_end - descs_start);
308 		out = malloc(length);
309 		out->header.magic = cpu_to_le32(FUNCTIONFS_DESCRIPTORS_MAGIC);
310 		out->header.length = cpu_to_le32(length);
311 		out->header.fs_count = cpu_to_le32(fs_count);
312 		out->header.hs_count = cpu_to_le32(hs_count);
313 		memcpy(out->descriptors, descs_start, descs_end - descs_start);
314 		*legacy = out;
315 	}
316 
317 	return length;
318 }
319 
320 
321 #define STR_INTERFACE_ "Source/Sink"
322 
323 static const struct {
324 	struct usb_functionfs_strings_head header;
325 	struct {
326 		__le16 code;
327 		const char str1[sizeof STR_INTERFACE_];
328 	} __attribute__((packed)) lang0;
329 } __attribute__((packed)) strings = {
330 	.header = {
331 		.magic = cpu_to_le32(FUNCTIONFS_STRINGS_MAGIC),
332 		.length = cpu_to_le32(sizeof strings),
333 		.str_count = cpu_to_le32(1),
334 		.lang_count = cpu_to_le32(1),
335 	},
336 	.lang0 = {
337 		cpu_to_le16(0x0409), /* en-us */
338 		STR_INTERFACE_,
339 	},
340 };
341 
342 #define STR_INTERFACE strings.lang0.str1
343 
344 
345 /******************** Files and Threads Handling ****************************/
346 
347 struct thread;
348 
349 static ssize_t read_wrap(struct thread *t, void *buf, size_t nbytes);
350 static ssize_t write_wrap(struct thread *t, const void *buf, size_t nbytes);
351 static ssize_t ep0_consume(struct thread *t, const void *buf, size_t nbytes);
352 static ssize_t fill_in_buf(struct thread *t, void *buf, size_t nbytes);
353 static ssize_t empty_out_buf(struct thread *t, const void *buf, size_t nbytes);
354 
355 
356 static struct thread {
357 	const char *const filename;
358 	size_t buf_size;
359 
360 	ssize_t (*in)(struct thread *, void *, size_t);
361 	const char *const in_name;
362 
363 	ssize_t (*out)(struct thread *, const void *, size_t);
364 	const char *const out_name;
365 
366 	int fd;
367 	pthread_t id;
368 	void *buf;
369 	ssize_t status;
370 } threads[] = {
371 	{
372 		"ep0", 4 * sizeof(struct usb_functionfs_event),
373 		read_wrap, NULL,
374 		ep0_consume, "<consume>",
375 		0, 0, NULL, 0
376 	},
377 	{
378 		"ep1", 8 * 1024,
379 		fill_in_buf, "<in>",
380 		write_wrap, NULL,
381 		0, 0, NULL, 0
382 	},
383 	{
384 		"ep2", 8 * 1024,
385 		read_wrap, NULL,
386 		empty_out_buf, "<out>",
387 		0, 0, NULL, 0
388 	},
389 };
390 
391 
392 static void init_thread(struct thread *t)
393 {
394 	t->buf = malloc(t->buf_size);
395 	die_on(!t->buf, "malloc");
396 
397 	t->fd = open(t->filename, O_RDWR);
398 	die_on(t->fd < 0, "%s", t->filename);
399 }
400 
401 static void cleanup_thread(void *arg)
402 {
403 	struct thread *t = arg;
404 	int ret, fd;
405 
406 	fd = t->fd;
407 	if (t->fd < 0)
408 		return;
409 	t->fd = -1;
410 
411 	/* test the FIFO ioctls (non-ep0 code paths) */
412 	if (t != threads) {
413 		ret = ioctl(fd, FUNCTIONFS_FIFO_STATUS);
414 		if (ret < 0) {
415 			/* ENODEV reported after disconnect */
416 			if (errno != ENODEV)
417 				err("%s: get fifo status", t->filename);
418 		} else if (ret) {
419 			warn("%s: unclaimed = %d\n", t->filename, ret);
420 			if (ioctl(fd, FUNCTIONFS_FIFO_FLUSH) < 0)
421 				err("%s: fifo flush", t->filename);
422 		}
423 	}
424 
425 	if (close(fd) < 0)
426 		err("%s: close", t->filename);
427 
428 	free(t->buf);
429 	t->buf = NULL;
430 }
431 
432 static void *start_thread_helper(void *arg)
433 {
434 	const char *name, *op, *in_name, *out_name;
435 	struct thread *t = arg;
436 	ssize_t ret;
437 
438 	info("%s: starts\n", t->filename);
439 	in_name = t->in_name ? t->in_name : t->filename;
440 	out_name = t->out_name ? t->out_name : t->filename;
441 
442 	pthread_cleanup_push(cleanup_thread, arg);
443 
444 	for (;;) {
445 		pthread_testcancel();
446 
447 		ret = t->in(t, t->buf, t->buf_size);
448 		if (ret > 0) {
449 			ret = t->out(t, t->buf, ret);
450 			name = out_name;
451 			op = "write";
452 		} else {
453 			name = in_name;
454 			op = "read";
455 		}
456 
457 		if (ret > 0) {
458 			/* nop */
459 		} else if (!ret) {
460 			debug("%s: %s: EOF", name, op);
461 			break;
462 		} else if (errno == EINTR || errno == EAGAIN) {
463 			debug("%s: %s", name, op);
464 		} else {
465 			warn("%s: %s", name, op);
466 			break;
467 		}
468 	}
469 
470 	pthread_cleanup_pop(1);
471 
472 	t->status = ret;
473 	info("%s: ends\n", t->filename);
474 	return NULL;
475 }
476 
477 static void start_thread(struct thread *t)
478 {
479 	debug("%s: starting\n", t->filename);
480 
481 	die_on(pthread_create(&t->id, NULL, start_thread_helper, t) < 0,
482 	       "pthread_create(%s)", t->filename);
483 }
484 
485 static void join_thread(struct thread *t)
486 {
487 	int ret = pthread_join(t->id, NULL);
488 
489 	if (ret < 0)
490 		err("%s: joining thread", t->filename);
491 	else
492 		debug("%s: joined\n", t->filename);
493 }
494 
495 
496 static ssize_t read_wrap(struct thread *t, void *buf, size_t nbytes)
497 {
498 	return read(t->fd, buf, nbytes);
499 }
500 
501 static ssize_t write_wrap(struct thread *t, const void *buf, size_t nbytes)
502 {
503 	return write(t->fd, buf, nbytes);
504 }
505 
506 
507 /******************** Empty/Fill buffer routines ****************************/
508 
509 /* 0 -- stream of zeros, 1 -- i % 63, 2 -- pipe */
510 enum pattern { PAT_ZERO, PAT_SEQ, PAT_PIPE };
511 static enum pattern pattern;
512 
513 static ssize_t
514 fill_in_buf(struct thread *ignore, void *buf, size_t nbytes)
515 {
516 	size_t i;
517 	__u8 *p;
518 
519 	(void)ignore;
520 
521 	switch (pattern) {
522 	case PAT_ZERO:
523 		memset(buf, 0, nbytes);
524 		break;
525 
526 	case PAT_SEQ:
527 		for (p = buf, i = 0; i < nbytes; ++i, ++p)
528 			*p = i % 63;
529 		break;
530 
531 	case PAT_PIPE:
532 		return fread(buf, 1, nbytes, stdin);
533 	}
534 
535 	return nbytes;
536 }
537 
538 static ssize_t
539 empty_out_buf(struct thread *ignore, const void *buf, size_t nbytes)
540 {
541 	const __u8 *p;
542 	__u8 expected;
543 	ssize_t ret;
544 	size_t len;
545 
546 	(void)ignore;
547 
548 	switch (pattern) {
549 	case PAT_ZERO:
550 		expected = 0;
551 		for (p = buf, len = 0; len < nbytes; ++p, ++len)
552 			if (*p)
553 				goto invalid;
554 		break;
555 
556 	case PAT_SEQ:
557 		for (p = buf, len = 0; len < nbytes; ++p, ++len)
558 			if (*p != len % 63) {
559 				expected = len % 63;
560 				goto invalid;
561 			}
562 		break;
563 
564 	case PAT_PIPE:
565 		ret = fwrite(buf, nbytes, 1, stdout);
566 		if (ret > 0)
567 			fflush(stdout);
568 		break;
569 
570 invalid:
571 		err("bad OUT byte %zd, expected %02x got %02x\n",
572 		    len, expected, *p);
573 		for (p = buf, len = 0; len < nbytes; ++p, ++len) {
574 			if (0 == (len % 32))
575 				fprintf(stderr, "%4zd:", len);
576 			fprintf(stderr, " %02x", *p);
577 			if (31 == (len % 32))
578 				fprintf(stderr, "\n");
579 		}
580 		fflush(stderr);
581 		errno = EILSEQ;
582 		return -1;
583 	}
584 
585 	return len;
586 }
587 
588 
589 /******************** Endpoints routines ************************************/
590 
591 static void handle_setup(const struct usb_ctrlrequest *setup)
592 {
593 	printf("bRequestType = %d\n", setup->bRequestType);
594 	printf("bRequest     = %d\n", setup->bRequest);
595 	printf("wValue       = %d\n", le16_to_cpu(setup->wValue));
596 	printf("wIndex       = %d\n", le16_to_cpu(setup->wIndex));
597 	printf("wLength      = %d\n", le16_to_cpu(setup->wLength));
598 }
599 
600 static ssize_t
601 ep0_consume(struct thread *ignore, const void *buf, size_t nbytes)
602 {
603 	static const char *const names[] = {
604 		[FUNCTIONFS_BIND] = "BIND",
605 		[FUNCTIONFS_UNBIND] = "UNBIND",
606 		[FUNCTIONFS_ENABLE] = "ENABLE",
607 		[FUNCTIONFS_DISABLE] = "DISABLE",
608 		[FUNCTIONFS_SETUP] = "SETUP",
609 		[FUNCTIONFS_SUSPEND] = "SUSPEND",
610 		[FUNCTIONFS_RESUME] = "RESUME",
611 	};
612 
613 	const struct usb_functionfs_event *event = buf;
614 	size_t n;
615 
616 	(void)ignore;
617 
618 	for (n = nbytes / sizeof *event; n; --n, ++event)
619 		switch (event->type) {
620 		case FUNCTIONFS_BIND:
621 		case FUNCTIONFS_UNBIND:
622 		case FUNCTIONFS_ENABLE:
623 		case FUNCTIONFS_DISABLE:
624 		case FUNCTIONFS_SETUP:
625 		case FUNCTIONFS_SUSPEND:
626 		case FUNCTIONFS_RESUME:
627 			printf("Event %s\n", names[event->type]);
628 			if (event->type == FUNCTIONFS_SETUP)
629 				handle_setup(&event->u.setup);
630 			break;
631 
632 		default:
633 			printf("Event %03u (unknown)\n", event->type);
634 		}
635 
636 	return nbytes;
637 }
638 
639 static void ep0_init(struct thread *t, bool legacy_descriptors)
640 {
641 	void *legacy;
642 	ssize_t ret;
643 	size_t len;
644 
645 	if (legacy_descriptors) {
646 		info("%s: writing descriptors\n", t->filename);
647 		goto legacy;
648 	}
649 
650 	info("%s: writing descriptors (in v2 format)\n", t->filename);
651 	ret = write(t->fd, &descriptors, sizeof descriptors);
652 
653 	if (ret < 0 && errno == EINVAL) {
654 		warn("%s: new format rejected, trying legacy\n", t->filename);
655 legacy:
656 		len = descs_to_legacy(&legacy, &descriptors);
657 		if (len) {
658 			ret = write(t->fd, legacy, len);
659 			free(legacy);
660 		}
661 	}
662 	die_on(ret < 0, "%s: write: descriptors", t->filename);
663 
664 	info("%s: writing strings\n", t->filename);
665 	ret = write(t->fd, &strings, sizeof strings);
666 	die_on(ret < 0, "%s: write: strings", t->filename);
667 }
668 
669 
670 /******************** Main **************************************************/
671 
672 int main(int argc, char **argv)
673 {
674 	bool legacy_descriptors;
675 	unsigned i;
676 
677 	legacy_descriptors = argc > 2 && !strcmp(argv[1], "-l");
678 
679 	init_thread(threads);
680 	ep0_init(threads, legacy_descriptors);
681 
682 	for (i = 1; i < sizeof threads / sizeof *threads; ++i)
683 		init_thread(threads + i);
684 
685 	for (i = 1; i < sizeof threads / sizeof *threads; ++i)
686 		start_thread(threads + i);
687 
688 	start_thread_helper(threads);
689 
690 	for (i = 1; i < sizeof threads / sizeof *threads; ++i)
691 		join_thread(threads + i);
692 
693 	return 0;
694 }
695