xref: /openbmc/u-boot/common/usb.c (revision 425faf74)
1 /*
2  * Most of this source has been derived from the Linux USB
3  * project:
4  * (C) Copyright Linus Torvalds 1999
5  * (C) Copyright Johannes Erdfelt 1999-2001
6  * (C) Copyright Andreas Gal 1999
7  * (C) Copyright Gregory P. Smith 1999
8  * (C) Copyright Deti Fliegl 1999 (new USB architecture)
9  * (C) Copyright Randy Dunlap 2000
10  * (C) Copyright David Brownell 2000 (kernel hotplug, usb_device_id)
11  * (C) Copyright Yggdrasil Computing, Inc. 2000
12  *     (usb_device_id matching changes by Adam J. Richter)
13  *
14  * Adapted for U-Boot:
15  * (C) Copyright 2001 Denis Peter, MPL AG Switzerland
16  *
17  * SPDX-License-Identifier:	GPL-2.0+
18  */
19 
20 /*
21  * How it works:
22  *
23  * Since this is a bootloader, the devices will not be automatic
24  * (re)configured on hotplug, but after a restart of the USB the
25  * device should work.
26  *
27  * For each transfer (except "Interrupt") we wait for completion.
28  */
29 #include <common.h>
30 #include <command.h>
31 #include <asm/processor.h>
32 #include <linux/compiler.h>
33 #include <linux/ctype.h>
34 #include <asm/byteorder.h>
35 #include <asm/unaligned.h>
36 
37 #include <usb.h>
38 #ifdef CONFIG_4xx
39 #include <asm/4xx_pci.h>
40 #endif
41 
42 #define USB_BUFSIZ	512
43 
44 static struct usb_device usb_dev[USB_MAX_DEVICE];
45 static int dev_index;
46 static int asynch_allowed;
47 
48 char usb_started; /* flag for the started/stopped USB status */
49 
50 #ifndef CONFIG_USB_MAX_CONTROLLER_COUNT
51 #define CONFIG_USB_MAX_CONTROLLER_COUNT 1
52 #endif
53 
54 /***************************************************************************
55  * Init USB Device
56  */
57 int usb_init(void)
58 {
59 	void *ctrl;
60 	struct usb_device *dev;
61 	int i, start_index = 0;
62 
63 	dev_index = 0;
64 	asynch_allowed = 1;
65 	usb_hub_reset();
66 
67 	/* first make all devices unknown */
68 	for (i = 0; i < USB_MAX_DEVICE; i++) {
69 		memset(&usb_dev[i], 0, sizeof(struct usb_device));
70 		usb_dev[i].devnum = -1;
71 	}
72 
73 	/* init low_level USB */
74 	for (i = 0; i < CONFIG_USB_MAX_CONTROLLER_COUNT; i++) {
75 		/* init low_level USB */
76 		printf("USB%d:   ", i);
77 		if (usb_lowlevel_init(i, &ctrl)) {
78 			puts("lowlevel init failed\n");
79 			continue;
80 		}
81 		/*
82 		 * lowlevel init is OK, now scan the bus for devices
83 		 * i.e. search HUBs and configure them
84 		 */
85 		start_index = dev_index;
86 		printf("scanning bus %d for devices... ", i);
87 		dev = usb_alloc_new_device(ctrl);
88 		/*
89 		 * device 0 is always present
90 		 * (root hub, so let it analyze)
91 		 */
92 		if (dev)
93 			usb_new_device(dev);
94 
95 		if (start_index == dev_index)
96 			puts("No USB Device found\n");
97 		else
98 			printf("%d USB Device(s) found\n",
99 				dev_index - start_index);
100 
101 		usb_started = 1;
102 	}
103 
104 	debug("scan end\n");
105 	/* if we were not able to find at least one working bus, bail out */
106 	if (!usb_started) {
107 		puts("USB error: all controllers failed lowlevel init\n");
108 		return -1;
109 	}
110 
111 	return 0;
112 }
113 
114 /******************************************************************************
115  * Stop USB this stops the LowLevel Part and deregisters USB devices.
116  */
117 int usb_stop(void)
118 {
119 	int i;
120 
121 	if (usb_started) {
122 		asynch_allowed = 1;
123 		usb_started = 0;
124 		usb_hub_reset();
125 
126 		for (i = 0; i < CONFIG_USB_MAX_CONTROLLER_COUNT; i++) {
127 			if (usb_lowlevel_stop(i))
128 				printf("failed to stop USB controller %d\n", i);
129 		}
130 	}
131 
132 	return 0;
133 }
134 
135 /*
136  * disables the asynch behaviour of the control message. This is used for data
137  * transfers that uses the exclusiv access to the control and bulk messages.
138  * Returns the old value so it can be restored later.
139  */
140 int usb_disable_asynch(int disable)
141 {
142 	int old_value = asynch_allowed;
143 
144 	asynch_allowed = !disable;
145 	return old_value;
146 }
147 
148 
149 /*-------------------------------------------------------------------
150  * Message wrappers.
151  *
152  */
153 
154 /*
155  * submits an Interrupt Message
156  */
157 int usb_submit_int_msg(struct usb_device *dev, unsigned long pipe,
158 			void *buffer, int transfer_len, int interval)
159 {
160 	return submit_int_msg(dev, pipe, buffer, transfer_len, interval);
161 }
162 
163 /*
164  * submits a control message and waits for comletion (at least timeout * 1ms)
165  * If timeout is 0, we don't wait for completion (used as example to set and
166  * clear keyboards LEDs). For data transfers, (storage transfers) we don't
167  * allow control messages with 0 timeout, by previousely resetting the flag
168  * asynch_allowed (usb_disable_asynch(1)).
169  * returns the transfered length if OK or -1 if error. The transfered length
170  * and the current status are stored in the dev->act_len and dev->status.
171  */
172 int usb_control_msg(struct usb_device *dev, unsigned int pipe,
173 			unsigned char request, unsigned char requesttype,
174 			unsigned short value, unsigned short index,
175 			void *data, unsigned short size, int timeout)
176 {
177 	ALLOC_CACHE_ALIGN_BUFFER(struct devrequest, setup_packet, 1);
178 
179 	if ((timeout == 0) && (!asynch_allowed)) {
180 		/* request for a asynch control pipe is not allowed */
181 		return -1;
182 	}
183 
184 	/* set setup command */
185 	setup_packet->requesttype = requesttype;
186 	setup_packet->request = request;
187 	setup_packet->value = cpu_to_le16(value);
188 	setup_packet->index = cpu_to_le16(index);
189 	setup_packet->length = cpu_to_le16(size);
190 	debug("usb_control_msg: request: 0x%X, requesttype: 0x%X, " \
191 	      "value 0x%X index 0x%X length 0x%X\n",
192 	      request, requesttype, value, index, size);
193 	dev->status = USB_ST_NOT_PROC; /*not yet processed */
194 
195 	if (submit_control_msg(dev, pipe, data, size, setup_packet) < 0)
196 		return -1;
197 	if (timeout == 0)
198 		return (int)size;
199 
200 	/*
201 	 * Wait for status to update until timeout expires, USB driver
202 	 * interrupt handler may set the status when the USB operation has
203 	 * been completed.
204 	 */
205 	while (timeout--) {
206 		if (!((volatile unsigned long)dev->status & USB_ST_NOT_PROC))
207 			break;
208 		mdelay(1);
209 	}
210 	if (dev->status)
211 		return -1;
212 
213 	return dev->act_len;
214 
215 }
216 
217 /*-------------------------------------------------------------------
218  * submits bulk message, and waits for completion. returns 0 if Ok or
219  * -1 if Error.
220  * synchronous behavior
221  */
222 int usb_bulk_msg(struct usb_device *dev, unsigned int pipe,
223 			void *data, int len, int *actual_length, int timeout)
224 {
225 	if (len < 0)
226 		return -1;
227 	dev->status = USB_ST_NOT_PROC; /*not yet processed */
228 	if (submit_bulk_msg(dev, pipe, data, len) < 0)
229 		return -1;
230 	while (timeout--) {
231 		if (!((volatile unsigned long)dev->status & USB_ST_NOT_PROC))
232 			break;
233 		mdelay(1);
234 	}
235 	*actual_length = dev->act_len;
236 	if (dev->status == 0)
237 		return 0;
238 	else
239 		return -1;
240 }
241 
242 
243 /*-------------------------------------------------------------------
244  * Max Packet stuff
245  */
246 
247 /*
248  * returns the max packet size, depending on the pipe direction and
249  * the configurations values
250  */
251 int usb_maxpacket(struct usb_device *dev, unsigned long pipe)
252 {
253 	/* direction is out -> use emaxpacket out */
254 	if ((pipe & USB_DIR_IN) == 0)
255 		return dev->epmaxpacketout[((pipe>>15) & 0xf)];
256 	else
257 		return dev->epmaxpacketin[((pipe>>15) & 0xf)];
258 }
259 
260 /*
261  * The routine usb_set_maxpacket_ep() is extracted from the loop of routine
262  * usb_set_maxpacket(), because the optimizer of GCC 4.x chokes on this routine
263  * when it is inlined in 1 single routine. What happens is that the register r3
264  * is used as loop-count 'i', but gets overwritten later on.
265  * This is clearly a compiler bug, but it is easier to workaround it here than
266  * to update the compiler (Occurs with at least several GCC 4.{1,2},x
267  * CodeSourcery compilers like e.g. 2007q3, 2008q1, 2008q3 lite editions on ARM)
268  *
269  * NOTE: Similar behaviour was observed with GCC4.6 on ARMv5.
270  */
271 static void noinline
272 usb_set_maxpacket_ep(struct usb_device *dev, int if_idx, int ep_idx)
273 {
274 	int b;
275 	struct usb_endpoint_descriptor *ep;
276 	u16 ep_wMaxPacketSize;
277 
278 	ep = &dev->config.if_desc[if_idx].ep_desc[ep_idx];
279 
280 	b = ep->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
281 	ep_wMaxPacketSize = get_unaligned(&ep->wMaxPacketSize);
282 
283 	if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
284 						USB_ENDPOINT_XFER_CONTROL) {
285 		/* Control => bidirectional */
286 		dev->epmaxpacketout[b] = ep_wMaxPacketSize;
287 		dev->epmaxpacketin[b] = ep_wMaxPacketSize;
288 		debug("##Control EP epmaxpacketout/in[%d] = %d\n",
289 		      b, dev->epmaxpacketin[b]);
290 	} else {
291 		if ((ep->bEndpointAddress & 0x80) == 0) {
292 			/* OUT Endpoint */
293 			if (ep_wMaxPacketSize > dev->epmaxpacketout[b]) {
294 				dev->epmaxpacketout[b] = ep_wMaxPacketSize;
295 				debug("##EP epmaxpacketout[%d] = %d\n",
296 				      b, dev->epmaxpacketout[b]);
297 			}
298 		} else {
299 			/* IN Endpoint */
300 			if (ep_wMaxPacketSize > dev->epmaxpacketin[b]) {
301 				dev->epmaxpacketin[b] = ep_wMaxPacketSize;
302 				debug("##EP epmaxpacketin[%d] = %d\n",
303 				      b, dev->epmaxpacketin[b]);
304 			}
305 		} /* if out */
306 	} /* if control */
307 }
308 
309 /*
310  * set the max packed value of all endpoints in the given configuration
311  */
312 static int usb_set_maxpacket(struct usb_device *dev)
313 {
314 	int i, ii;
315 
316 	for (i = 0; i < dev->config.desc.bNumInterfaces; i++)
317 		for (ii = 0; ii < dev->config.if_desc[i].desc.bNumEndpoints; ii++)
318 			usb_set_maxpacket_ep(dev, i, ii);
319 
320 	return 0;
321 }
322 
323 /*******************************************************************************
324  * Parse the config, located in buffer, and fills the dev->config structure.
325  * Note that all little/big endian swapping are done automatically.
326  */
327 static int usb_parse_config(struct usb_device *dev,
328 			unsigned char *buffer, int cfgno)
329 {
330 	struct usb_descriptor_header *head;
331 	int index, ifno, epno, curr_if_num;
332 	u16 ep_wMaxPacketSize;
333 	struct usb_interface *if_desc = NULL;
334 
335 	ifno = -1;
336 	epno = -1;
337 	curr_if_num = -1;
338 
339 	dev->configno = cfgno;
340 	head = (struct usb_descriptor_header *) &buffer[0];
341 	if (head->bDescriptorType != USB_DT_CONFIG) {
342 		printf(" ERROR: NOT USB_CONFIG_DESC %x\n",
343 			head->bDescriptorType);
344 		return -1;
345 	}
346 	memcpy(&dev->config, buffer, buffer[0]);
347 	le16_to_cpus(&(dev->config.desc.wTotalLength));
348 	dev->config.no_of_if = 0;
349 
350 	index = dev->config.desc.bLength;
351 	/* Ok the first entry must be a configuration entry,
352 	 * now process the others */
353 	head = (struct usb_descriptor_header *) &buffer[index];
354 	while (index + 1 < dev->config.desc.wTotalLength) {
355 		switch (head->bDescriptorType) {
356 		case USB_DT_INTERFACE:
357 			if (((struct usb_interface_descriptor *) \
358 			     &buffer[index])->bInterfaceNumber != curr_if_num) {
359 				/* this is a new interface, copy new desc */
360 				ifno = dev->config.no_of_if;
361 				if_desc = &dev->config.if_desc[ifno];
362 				dev->config.no_of_if++;
363 				memcpy(if_desc,	&buffer[index], buffer[index]);
364 				if_desc->no_of_ep = 0;
365 				if_desc->num_altsetting = 1;
366 				curr_if_num =
367 				     if_desc->desc.bInterfaceNumber;
368 			} else {
369 				/* found alternate setting for the interface */
370 				if (ifno >= 0) {
371 					if_desc = &dev->config.if_desc[ifno];
372 					if_desc->num_altsetting++;
373 				}
374 			}
375 			break;
376 		case USB_DT_ENDPOINT:
377 			epno = dev->config.if_desc[ifno].no_of_ep;
378 			if_desc = &dev->config.if_desc[ifno];
379 			/* found an endpoint */
380 			if_desc->no_of_ep++;
381 			memcpy(&if_desc->ep_desc[epno],
382 				&buffer[index], buffer[index]);
383 			ep_wMaxPacketSize = get_unaligned(&dev->config.\
384 							if_desc[ifno].\
385 							ep_desc[epno].\
386 							wMaxPacketSize);
387 			put_unaligned(le16_to_cpu(ep_wMaxPacketSize),
388 					&dev->config.\
389 					if_desc[ifno].\
390 					ep_desc[epno].\
391 					wMaxPacketSize);
392 			debug("if %d, ep %d\n", ifno, epno);
393 			break;
394 		case USB_DT_SS_ENDPOINT_COMP:
395 			if_desc = &dev->config.if_desc[ifno];
396 			memcpy(&if_desc->ss_ep_comp_desc[epno],
397 				&buffer[index], buffer[index]);
398 			break;
399 		default:
400 			if (head->bLength == 0)
401 				return 1;
402 
403 			debug("unknown Description Type : %x\n",
404 			      head->bDescriptorType);
405 
406 #ifdef DEBUG
407 			{
408 				unsigned char *ch = (unsigned char *)head;
409 				int i;
410 
411 				for (i = 0; i < head->bLength; i++)
412 					debug("%02X ", *ch++);
413 				debug("\n\n\n");
414 			}
415 #endif
416 			break;
417 		}
418 		index += head->bLength;
419 		head = (struct usb_descriptor_header *)&buffer[index];
420 	}
421 	return 1;
422 }
423 
424 /***********************************************************************
425  * Clears an endpoint
426  * endp: endpoint number in bits 0-3;
427  * direction flag in bit 7 (1 = IN, 0 = OUT)
428  */
429 int usb_clear_halt(struct usb_device *dev, int pipe)
430 {
431 	int result;
432 	int endp = usb_pipeendpoint(pipe)|(usb_pipein(pipe)<<7);
433 
434 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
435 				 USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT, 0,
436 				 endp, NULL, 0, USB_CNTL_TIMEOUT * 3);
437 
438 	/* don't clear if failed */
439 	if (result < 0)
440 		return result;
441 
442 	/*
443 	 * NOTE: we do not get status and verify reset was successful
444 	 * as some devices are reported to lock up upon this check..
445 	 */
446 
447 	usb_endpoint_running(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe));
448 
449 	/* toggle is reset on clear */
450 	usb_settoggle(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe), 0);
451 	return 0;
452 }
453 
454 
455 /**********************************************************************
456  * get_descriptor type
457  */
458 static int usb_get_descriptor(struct usb_device *dev, unsigned char type,
459 			unsigned char index, void *buf, int size)
460 {
461 	int res;
462 	res = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
463 			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
464 			(type << 8) + index, 0,
465 			buf, size, USB_CNTL_TIMEOUT);
466 	return res;
467 }
468 
469 /**********************************************************************
470  * gets configuration cfgno and store it in the buffer
471  */
472 int usb_get_configuration_no(struct usb_device *dev,
473 			     unsigned char *buffer, int cfgno)
474 {
475 	int result;
476 	unsigned int tmp;
477 	struct usb_config_descriptor *config;
478 
479 	config = (struct usb_config_descriptor *)&buffer[0];
480 	result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno, buffer, 9);
481 	if (result < 9) {
482 		if (result < 0)
483 			printf("unable to get descriptor, error %lX\n",
484 				dev->status);
485 		else
486 			printf("config descriptor too short " \
487 				"(expected %i, got %i)\n", 9, result);
488 		return -1;
489 	}
490 	tmp = le16_to_cpu(config->wTotalLength);
491 
492 	if (tmp > USB_BUFSIZ) {
493 		printf("usb_get_configuration_no: failed to get " \
494 		       "descriptor - too long: %d\n", tmp);
495 		return -1;
496 	}
497 
498 	result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno, buffer, tmp);
499 	debug("get_conf_no %d Result %d, wLength %d\n", cfgno, result, tmp);
500 	return result;
501 }
502 
503 /********************************************************************
504  * set address of a device to the value in dev->devnum.
505  * This can only be done by addressing the device via the default address (0)
506  */
507 static int usb_set_address(struct usb_device *dev)
508 {
509 	int res;
510 
511 	debug("set address %d\n", dev->devnum);
512 	res = usb_control_msg(dev, usb_snddefctrl(dev),
513 				USB_REQ_SET_ADDRESS, 0,
514 				(dev->devnum), 0,
515 				NULL, 0, USB_CNTL_TIMEOUT);
516 	return res;
517 }
518 
519 /********************************************************************
520  * set interface number to interface
521  */
522 int usb_set_interface(struct usb_device *dev, int interface, int alternate)
523 {
524 	struct usb_interface *if_face = NULL;
525 	int ret, i;
526 
527 	for (i = 0; i < dev->config.desc.bNumInterfaces; i++) {
528 		if (dev->config.if_desc[i].desc.bInterfaceNumber == interface) {
529 			if_face = &dev->config.if_desc[i];
530 			break;
531 		}
532 	}
533 	if (!if_face) {
534 		printf("selecting invalid interface %d", interface);
535 		return -1;
536 	}
537 	/*
538 	 * We should return now for devices with only one alternate setting.
539 	 * According to 9.4.10 of the Universal Serial Bus Specification
540 	 * Revision 2.0 such devices can return with a STALL. This results in
541 	 * some USB sticks timeouting during initialization and then being
542 	 * unusable in U-Boot.
543 	 */
544 	if (if_face->num_altsetting == 1)
545 		return 0;
546 
547 	ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
548 				USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE,
549 				alternate, interface, NULL, 0,
550 				USB_CNTL_TIMEOUT * 5);
551 	if (ret < 0)
552 		return ret;
553 
554 	return 0;
555 }
556 
557 /********************************************************************
558  * set configuration number to configuration
559  */
560 static int usb_set_configuration(struct usb_device *dev, int configuration)
561 {
562 	int res;
563 	debug("set configuration %d\n", configuration);
564 	/* set setup command */
565 	res = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
566 				USB_REQ_SET_CONFIGURATION, 0,
567 				configuration, 0,
568 				NULL, 0, USB_CNTL_TIMEOUT);
569 	if (res == 0) {
570 		dev->toggle[0] = 0;
571 		dev->toggle[1] = 0;
572 		return 0;
573 	} else
574 		return -1;
575 }
576 
577 /********************************************************************
578  * set protocol to protocol
579  */
580 int usb_set_protocol(struct usb_device *dev, int ifnum, int protocol)
581 {
582 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
583 		USB_REQ_SET_PROTOCOL, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
584 		protocol, ifnum, NULL, 0, USB_CNTL_TIMEOUT);
585 }
586 
587 /********************************************************************
588  * set idle
589  */
590 int usb_set_idle(struct usb_device *dev, int ifnum, int duration, int report_id)
591 {
592 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
593 		USB_REQ_SET_IDLE, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
594 		(duration << 8) | report_id, ifnum, NULL, 0, USB_CNTL_TIMEOUT);
595 }
596 
597 /********************************************************************
598  * get report
599  */
600 int usb_get_report(struct usb_device *dev, int ifnum, unsigned char type,
601 		   unsigned char id, void *buf, int size)
602 {
603 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
604 			USB_REQ_GET_REPORT,
605 			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
606 			(type << 8) + id, ifnum, buf, size, USB_CNTL_TIMEOUT);
607 }
608 
609 /********************************************************************
610  * get class descriptor
611  */
612 int usb_get_class_descriptor(struct usb_device *dev, int ifnum,
613 		unsigned char type, unsigned char id, void *buf, int size)
614 {
615 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
616 		USB_REQ_GET_DESCRIPTOR, USB_RECIP_INTERFACE | USB_DIR_IN,
617 		(type << 8) + id, ifnum, buf, size, USB_CNTL_TIMEOUT);
618 }
619 
620 /********************************************************************
621  * get string index in buffer
622  */
623 static int usb_get_string(struct usb_device *dev, unsigned short langid,
624 		   unsigned char index, void *buf, int size)
625 {
626 	int i;
627 	int result;
628 
629 	for (i = 0; i < 3; ++i) {
630 		/* some devices are flaky */
631 		result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
632 			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
633 			(USB_DT_STRING << 8) + index, langid, buf, size,
634 			USB_CNTL_TIMEOUT);
635 
636 		if (result > 0)
637 			break;
638 	}
639 
640 	return result;
641 }
642 
643 
644 static void usb_try_string_workarounds(unsigned char *buf, int *length)
645 {
646 	int newlength, oldlength = *length;
647 
648 	for (newlength = 2; newlength + 1 < oldlength; newlength += 2)
649 		if (!isprint(buf[newlength]) || buf[newlength + 1])
650 			break;
651 
652 	if (newlength > 2) {
653 		buf[0] = newlength;
654 		*length = newlength;
655 	}
656 }
657 
658 
659 static int usb_string_sub(struct usb_device *dev, unsigned int langid,
660 		unsigned int index, unsigned char *buf)
661 {
662 	int rc;
663 
664 	/* Try to read the string descriptor by asking for the maximum
665 	 * possible number of bytes */
666 	rc = usb_get_string(dev, langid, index, buf, 255);
667 
668 	/* If that failed try to read the descriptor length, then
669 	 * ask for just that many bytes */
670 	if (rc < 2) {
671 		rc = usb_get_string(dev, langid, index, buf, 2);
672 		if (rc == 2)
673 			rc = usb_get_string(dev, langid, index, buf, buf[0]);
674 	}
675 
676 	if (rc >= 2) {
677 		if (!buf[0] && !buf[1])
678 			usb_try_string_workarounds(buf, &rc);
679 
680 		/* There might be extra junk at the end of the descriptor */
681 		if (buf[0] < rc)
682 			rc = buf[0];
683 
684 		rc = rc - (rc & 1); /* force a multiple of two */
685 	}
686 
687 	if (rc < 2)
688 		rc = -1;
689 
690 	return rc;
691 }
692 
693 
694 /********************************************************************
695  * usb_string:
696  * Get string index and translate it to ascii.
697  * returns string length (> 0) or error (< 0)
698  */
699 int usb_string(struct usb_device *dev, int index, char *buf, size_t size)
700 {
701 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, mybuf, USB_BUFSIZ);
702 	unsigned char *tbuf;
703 	int err;
704 	unsigned int u, idx;
705 
706 	if (size <= 0 || !buf || !index)
707 		return -1;
708 	buf[0] = 0;
709 	tbuf = &mybuf[0];
710 
711 	/* get langid for strings if it's not yet known */
712 	if (!dev->have_langid) {
713 		err = usb_string_sub(dev, 0, 0, tbuf);
714 		if (err < 0) {
715 			debug("error getting string descriptor 0 " \
716 			      "(error=%lx)\n", dev->status);
717 			return -1;
718 		} else if (tbuf[0] < 4) {
719 			debug("string descriptor 0 too short\n");
720 			return -1;
721 		} else {
722 			dev->have_langid = -1;
723 			dev->string_langid = tbuf[2] | (tbuf[3] << 8);
724 				/* always use the first langid listed */
725 			debug("USB device number %d default " \
726 			      "language ID 0x%x\n",
727 			      dev->devnum, dev->string_langid);
728 		}
729 	}
730 
731 	err = usb_string_sub(dev, dev->string_langid, index, tbuf);
732 	if (err < 0)
733 		return err;
734 
735 	size--;		/* leave room for trailing NULL char in output buffer */
736 	for (idx = 0, u = 2; u < err; u += 2) {
737 		if (idx >= size)
738 			break;
739 		if (tbuf[u+1])			/* high byte */
740 			buf[idx++] = '?';  /* non-ASCII character */
741 		else
742 			buf[idx++] = tbuf[u];
743 	}
744 	buf[idx] = 0;
745 	err = idx;
746 	return err;
747 }
748 
749 
750 /********************************************************************
751  * USB device handling:
752  * the USB device are static allocated [USB_MAX_DEVICE].
753  */
754 
755 
756 /* returns a pointer to the device with the index [index].
757  * if the device is not assigned (dev->devnum==-1) returns NULL
758  */
759 struct usb_device *usb_get_dev_index(int index)
760 {
761 	if (usb_dev[index].devnum == -1)
762 		return NULL;
763 	else
764 		return &usb_dev[index];
765 }
766 
767 /* returns a pointer of a new device structure or NULL, if
768  * no device struct is available
769  */
770 struct usb_device *usb_alloc_new_device(void *controller)
771 {
772 	int i;
773 	debug("New Device %d\n", dev_index);
774 	if (dev_index == USB_MAX_DEVICE) {
775 		printf("ERROR, too many USB Devices, max=%d\n", USB_MAX_DEVICE);
776 		return NULL;
777 	}
778 	/* default Address is 0, real addresses start with 1 */
779 	usb_dev[dev_index].devnum = dev_index + 1;
780 	usb_dev[dev_index].maxchild = 0;
781 	for (i = 0; i < USB_MAXCHILDREN; i++)
782 		usb_dev[dev_index].children[i] = NULL;
783 	usb_dev[dev_index].parent = NULL;
784 	usb_dev[dev_index].controller = controller;
785 	dev_index++;
786 	return &usb_dev[dev_index - 1];
787 }
788 
789 /*
790  * Free the newly created device node.
791  * Called in error cases where configuring a newly attached
792  * device fails for some reason.
793  */
794 void usb_free_device(void)
795 {
796 	dev_index--;
797 	debug("Freeing device node: %d\n", dev_index);
798 	memset(&usb_dev[dev_index], 0, sizeof(struct usb_device));
799 	usb_dev[dev_index].devnum = -1;
800 }
801 
802 /*
803  * By the time we get here, the device has gotten a new device ID
804  * and is in the default state. We need to identify the thing and
805  * get the ball rolling..
806  *
807  * Returns 0 for success, != 0 for error.
808  */
809 int usb_new_device(struct usb_device *dev)
810 {
811 	int addr, err;
812 	int tmp;
813 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, tmpbuf, USB_BUFSIZ);
814 
815 	/* We still haven't set the Address yet */
816 	addr = dev->devnum;
817 	dev->devnum = 0;
818 
819 #ifdef CONFIG_LEGACY_USB_INIT_SEQ
820 	/* this is the old and known way of initializing devices, it is
821 	 * different than what Windows and Linux are doing. Windows and Linux
822 	 * both retrieve 64 bytes while reading the device descriptor
823 	 * Several USB stick devices report ERR: CTL_TIMEOUT, caused by an
824 	 * invalid header while reading 8 bytes as device descriptor. */
825 	dev->descriptor.bMaxPacketSize0 = 8;	    /* Start off at 8 bytes  */
826 	dev->maxpacketsize = PACKET_SIZE_8;
827 	dev->epmaxpacketin[0] = 8;
828 	dev->epmaxpacketout[0] = 8;
829 
830 	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0, tmpbuf, 8);
831 	if (err < 8) {
832 		printf("\n      USB device not responding, " \
833 		       "giving up (status=%lX)\n", dev->status);
834 		return 1;
835 	}
836 	memcpy(&dev->descriptor, tmpbuf, 8);
837 #else
838 	/* This is a Windows scheme of initialization sequence, with double
839 	 * reset of the device (Linux uses the same sequence)
840 	 * Some equipment is said to work only with such init sequence; this
841 	 * patch is based on the work by Alan Stern:
842 	 * http://sourceforge.net/mailarchive/forum.php?
843 	 * thread_id=5729457&forum_id=5398
844 	 */
845 	struct usb_device_descriptor *desc;
846 	int port = -1;
847 	struct usb_device *parent = dev->parent;
848 	unsigned short portstatus;
849 
850 	/* send 64-byte GET-DEVICE-DESCRIPTOR request.  Since the descriptor is
851 	 * only 18 bytes long, this will terminate with a short packet.  But if
852 	 * the maxpacket size is 8 or 16 the device may be waiting to transmit
853 	 * some more, or keeps on retransmitting the 8 byte header. */
854 
855 	desc = (struct usb_device_descriptor *)tmpbuf;
856 	dev->descriptor.bMaxPacketSize0 = 64;	    /* Start off at 64 bytes  */
857 	/* Default to 64 byte max packet size */
858 	dev->maxpacketsize = PACKET_SIZE_64;
859 	dev->epmaxpacketin[0] = 64;
860 	dev->epmaxpacketout[0] = 64;
861 
862 	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, 64);
863 	if (err < 0) {
864 		debug("usb_new_device: usb_get_descriptor() failed\n");
865 		return 1;
866 	}
867 
868 	dev->descriptor.bMaxPacketSize0 = desc->bMaxPacketSize0;
869 	/*
870 	 * Fetch the device class, driver can use this info
871 	 * to differentiate between HUB and DEVICE.
872 	 */
873 	dev->descriptor.bDeviceClass = desc->bDeviceClass;
874 
875 	/* find the port number we're at */
876 	if (parent) {
877 		int j;
878 
879 		for (j = 0; j < parent->maxchild; j++) {
880 			if (parent->children[j] == dev) {
881 				port = j;
882 				break;
883 			}
884 		}
885 		if (port < 0) {
886 			printf("usb_new_device:cannot locate device's port.\n");
887 			return 1;
888 		}
889 
890 		/* reset the port for the second time */
891 		err = hub_port_reset(dev->parent, port, &portstatus);
892 		if (err < 0) {
893 			printf("\n     Couldn't reset port %i\n", port);
894 			return 1;
895 		}
896 	}
897 #endif
898 
899 	dev->epmaxpacketin[0] = dev->descriptor.bMaxPacketSize0;
900 	dev->epmaxpacketout[0] = dev->descriptor.bMaxPacketSize0;
901 	switch (dev->descriptor.bMaxPacketSize0) {
902 	case 8:
903 		dev->maxpacketsize  = PACKET_SIZE_8;
904 		break;
905 	case 16:
906 		dev->maxpacketsize = PACKET_SIZE_16;
907 		break;
908 	case 32:
909 		dev->maxpacketsize = PACKET_SIZE_32;
910 		break;
911 	case 64:
912 		dev->maxpacketsize = PACKET_SIZE_64;
913 		break;
914 	}
915 	dev->devnum = addr;
916 
917 	err = usb_set_address(dev); /* set address */
918 
919 	if (err < 0) {
920 		printf("\n      USB device not accepting new address " \
921 			"(error=%lX)\n", dev->status);
922 		return 1;
923 	}
924 
925 	mdelay(10);	/* Let the SET_ADDRESS settle */
926 
927 	tmp = sizeof(dev->descriptor);
928 
929 	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0,
930 				 tmpbuf, sizeof(dev->descriptor));
931 	if (err < tmp) {
932 		if (err < 0)
933 			printf("unable to get device descriptor (error=%d)\n",
934 			       err);
935 		else
936 			printf("USB device descriptor short read " \
937 				"(expected %i, got %i)\n", tmp, err);
938 		return 1;
939 	}
940 	memcpy(&dev->descriptor, tmpbuf, sizeof(dev->descriptor));
941 	/* correct le values */
942 	le16_to_cpus(&dev->descriptor.bcdUSB);
943 	le16_to_cpus(&dev->descriptor.idVendor);
944 	le16_to_cpus(&dev->descriptor.idProduct);
945 	le16_to_cpus(&dev->descriptor.bcdDevice);
946 	/* only support for one config for now */
947 	err = usb_get_configuration_no(dev, tmpbuf, 0);
948 	if (err < 0) {
949 		printf("usb_new_device: Cannot read configuration, " \
950 		       "skipping device %04x:%04x\n",
951 		       dev->descriptor.idVendor, dev->descriptor.idProduct);
952 		return -1;
953 	}
954 	usb_parse_config(dev, tmpbuf, 0);
955 	usb_set_maxpacket(dev);
956 	/* we set the default configuration here */
957 	if (usb_set_configuration(dev, dev->config.desc.bConfigurationValue)) {
958 		printf("failed to set default configuration " \
959 			"len %d, status %lX\n", dev->act_len, dev->status);
960 		return -1;
961 	}
962 	debug("new device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
963 	      dev->descriptor.iManufacturer, dev->descriptor.iProduct,
964 	      dev->descriptor.iSerialNumber);
965 	memset(dev->mf, 0, sizeof(dev->mf));
966 	memset(dev->prod, 0, sizeof(dev->prod));
967 	memset(dev->serial, 0, sizeof(dev->serial));
968 	if (dev->descriptor.iManufacturer)
969 		usb_string(dev, dev->descriptor.iManufacturer,
970 			   dev->mf, sizeof(dev->mf));
971 	if (dev->descriptor.iProduct)
972 		usb_string(dev, dev->descriptor.iProduct,
973 			   dev->prod, sizeof(dev->prod));
974 	if (dev->descriptor.iSerialNumber)
975 		usb_string(dev, dev->descriptor.iSerialNumber,
976 			   dev->serial, sizeof(dev->serial));
977 	debug("Manufacturer %s\n", dev->mf);
978 	debug("Product      %s\n", dev->prod);
979 	debug("SerialNumber %s\n", dev->serial);
980 	/* now prode if the device is a hub */
981 	usb_hub_probe(dev, 0);
982 	return 0;
983 }
984 
985 /* EOF */
986