xref: /rk3399_rockchip-uboot/common/usb.c (revision 605bd75af565011aa46e6d80a32e2aa03aff8159)
1 /*
2  *
3  * Most of this source has been derived from the Linux USB
4  * project:
5  * (C) Copyright Linus Torvalds 1999
6  * (C) Copyright Johannes Erdfelt 1999-2001
7  * (C) Copyright Andreas Gal 1999
8  * (C) Copyright Gregory P. Smith 1999
9  * (C) Copyright Deti Fliegl 1999 (new USB architecture)
10  * (C) Copyright Randy Dunlap 2000
11  * (C) Copyright David Brownell 2000 (kernel hotplug, usb_device_id)
12  * (C) Copyright Yggdrasil Computing, Inc. 2000
13  *     (usb_device_id matching changes by Adam J. Richter)
14  *
15  * Adapted for U-Boot:
16  * (C) Copyright 2001 Denis Peter, MPL AG Switzerland
17  *
18  * See file CREDITS for list of people who contributed to this
19  * project.
20  *
21  * This program is free software; you can redistribute it and/or
22  * modify it under the terms of the GNU General Public License as
23  * published by the Free Software Foundation; either version 2 of
24  * the License, or (at your option) any later version.
25  *
26  * This program is distributed in the hope that it will be useful,
27  * but WITHOUT ANY WARRANTY; without even the implied warranty of
28  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
29  * GNU General Public License for more details.
30  *
31  * You should have received a copy of the GNU General Public License
32  * along with this program; if not, write to the Free Software
33  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
34  * MA 02111-1307 USA
35  *
36  */
37 
38 /*
39  * How it works:
40  *
41  * Since this is a bootloader, the devices will not be automatic
42  * (re)configured on hotplug, but after a restart of the USB the
43  * device should work.
44  *
45  * For each transfer (except "Interrupt") we wait for completion.
46  */
47 #include <common.h>
48 #include <command.h>
49 #include <asm/processor.h>
50 #include <linux/compiler.h>
51 #include <linux/ctype.h>
52 #include <asm/byteorder.h>
53 #include <asm/unaligned.h>
54 
55 #include <usb.h>
56 #ifdef CONFIG_4xx
57 #include <asm/4xx_pci.h>
58 #endif
59 
60 #define USB_BUFSIZ	512
61 
62 static struct usb_device usb_dev[USB_MAX_DEVICE];
63 static int dev_index;
64 static int asynch_allowed;
65 
66 char usb_started; /* flag for the started/stopped USB status */
67 
68 #ifndef CONFIG_USB_MAX_CONTROLLER_COUNT
69 #define CONFIG_USB_MAX_CONTROLLER_COUNT 1
70 #endif
71 
72 /***************************************************************************
73  * Init USB Device
74  */
75 int usb_init(void)
76 {
77 	void *ctrl;
78 	struct usb_device *dev;
79 	int i, start_index = 0;
80 
81 	dev_index = 0;
82 	asynch_allowed = 1;
83 	usb_hub_reset();
84 
85 	/* first make all devices unknown */
86 	for (i = 0; i < USB_MAX_DEVICE; i++) {
87 		memset(&usb_dev[i], 0, sizeof(struct usb_device));
88 		usb_dev[i].devnum = -1;
89 	}
90 
91 	/* init low_level USB */
92 	for (i = 0; i < CONFIG_USB_MAX_CONTROLLER_COUNT; i++) {
93 		/* init low_level USB */
94 		printf("USB%d:   ", i);
95 		if (usb_lowlevel_init(i, &ctrl)) {
96 			puts("lowlevel init failed\n");
97 			continue;
98 		}
99 		/*
100 		 * lowlevel init is OK, now scan the bus for devices
101 		 * i.e. search HUBs and configure them
102 		 */
103 		start_index = dev_index;
104 		printf("scanning bus %d for devices... ", i);
105 		dev = usb_alloc_new_device(ctrl);
106 		/*
107 		 * device 0 is always present
108 		 * (root hub, so let it analyze)
109 		 */
110 		if (dev)
111 			usb_new_device(dev);
112 
113 		if (start_index == dev_index)
114 			puts("No USB Device found\n");
115 		else
116 			printf("%d USB Device(s) found\n",
117 				dev_index - start_index);
118 
119 		usb_started = 1;
120 	}
121 
122 	debug("scan end\n");
123 	/* if we were not able to find at least one working bus, bail out */
124 	if (!usb_started) {
125 		puts("USB error: all controllers failed lowlevel init\n");
126 		return -1;
127 	}
128 
129 	return 0;
130 }
131 
132 /******************************************************************************
133  * Stop USB this stops the LowLevel Part and deregisters USB devices.
134  */
135 int usb_stop(void)
136 {
137 	int i;
138 
139 	if (usb_started) {
140 		asynch_allowed = 1;
141 		usb_started = 0;
142 		usb_hub_reset();
143 
144 		for (i = 0; i < CONFIG_USB_MAX_CONTROLLER_COUNT; i++) {
145 			if (usb_lowlevel_stop(i))
146 				printf("failed to stop USB controller %d\n", i);
147 		}
148 	}
149 
150 	return 0;
151 }
152 
153 /*
154  * disables the asynch behaviour of the control message. This is used for data
155  * transfers that uses the exclusiv access to the control and bulk messages.
156  * Returns the old value so it can be restored later.
157  */
158 int usb_disable_asynch(int disable)
159 {
160 	int old_value = asynch_allowed;
161 
162 	asynch_allowed = !disable;
163 	return old_value;
164 }
165 
166 
167 /*-------------------------------------------------------------------
168  * Message wrappers.
169  *
170  */
171 
172 /*
173  * submits an Interrupt Message
174  */
175 int usb_submit_int_msg(struct usb_device *dev, unsigned long pipe,
176 			void *buffer, int transfer_len, int interval)
177 {
178 	return submit_int_msg(dev, pipe, buffer, transfer_len, interval);
179 }
180 
181 /*
182  * submits a control message and waits for comletion (at least timeout * 1ms)
183  * If timeout is 0, we don't wait for completion (used as example to set and
184  * clear keyboards LEDs). For data transfers, (storage transfers) we don't
185  * allow control messages with 0 timeout, by previousely resetting the flag
186  * asynch_allowed (usb_disable_asynch(1)).
187  * returns the transfered length if OK or -1 if error. The transfered length
188  * and the current status are stored in the dev->act_len and dev->status.
189  */
190 int usb_control_msg(struct usb_device *dev, unsigned int pipe,
191 			unsigned char request, unsigned char requesttype,
192 			unsigned short value, unsigned short index,
193 			void *data, unsigned short size, int timeout)
194 {
195 	ALLOC_CACHE_ALIGN_BUFFER(struct devrequest, setup_packet, 1);
196 
197 	if ((timeout == 0) && (!asynch_allowed)) {
198 		/* request for a asynch control pipe is not allowed */
199 		return -1;
200 	}
201 
202 	/* set setup command */
203 	setup_packet->requesttype = requesttype;
204 	setup_packet->request = request;
205 	setup_packet->value = cpu_to_le16(value);
206 	setup_packet->index = cpu_to_le16(index);
207 	setup_packet->length = cpu_to_le16(size);
208 	debug("usb_control_msg: request: 0x%X, requesttype: 0x%X, " \
209 	      "value 0x%X index 0x%X length 0x%X\n",
210 	      request, requesttype, value, index, size);
211 	dev->status = USB_ST_NOT_PROC; /*not yet processed */
212 
213 	if (submit_control_msg(dev, pipe, data, size, setup_packet) < 0)
214 		return -1;
215 	if (timeout == 0)
216 		return (int)size;
217 
218 	/*
219 	 * Wait for status to update until timeout expires, USB driver
220 	 * interrupt handler may set the status when the USB operation has
221 	 * been completed.
222 	 */
223 	while (timeout--) {
224 		if (!((volatile unsigned long)dev->status & USB_ST_NOT_PROC))
225 			break;
226 		mdelay(1);
227 	}
228 	if (dev->status)
229 		return -1;
230 
231 	return dev->act_len;
232 
233 }
234 
235 /*-------------------------------------------------------------------
236  * submits bulk message, and waits for completion. returns 0 if Ok or
237  * -1 if Error.
238  * synchronous behavior
239  */
240 int usb_bulk_msg(struct usb_device *dev, unsigned int pipe,
241 			void *data, int len, int *actual_length, int timeout)
242 {
243 	if (len < 0)
244 		return -1;
245 	dev->status = USB_ST_NOT_PROC; /*not yet processed */
246 	if (submit_bulk_msg(dev, pipe, data, len) < 0)
247 		return -1;
248 	while (timeout--) {
249 		if (!((volatile unsigned long)dev->status & USB_ST_NOT_PROC))
250 			break;
251 		mdelay(1);
252 	}
253 	*actual_length = dev->act_len;
254 	if (dev->status == 0)
255 		return 0;
256 	else
257 		return -1;
258 }
259 
260 
261 /*-------------------------------------------------------------------
262  * Max Packet stuff
263  */
264 
265 /*
266  * returns the max packet size, depending on the pipe direction and
267  * the configurations values
268  */
269 int usb_maxpacket(struct usb_device *dev, unsigned long pipe)
270 {
271 	/* direction is out -> use emaxpacket out */
272 	if ((pipe & USB_DIR_IN) == 0)
273 		return dev->epmaxpacketout[((pipe>>15) & 0xf)];
274 	else
275 		return dev->epmaxpacketin[((pipe>>15) & 0xf)];
276 }
277 
278 /*
279  * The routine usb_set_maxpacket_ep() is extracted from the loop of routine
280  * usb_set_maxpacket(), because the optimizer of GCC 4.x chokes on this routine
281  * when it is inlined in 1 single routine. What happens is that the register r3
282  * is used as loop-count 'i', but gets overwritten later on.
283  * This is clearly a compiler bug, but it is easier to workaround it here than
284  * to update the compiler (Occurs with at least several GCC 4.{1,2},x
285  * CodeSourcery compilers like e.g. 2007q3, 2008q1, 2008q3 lite editions on ARM)
286  *
287  * NOTE: Similar behaviour was observed with GCC4.6 on ARMv5.
288  */
289 static void noinline
290 usb_set_maxpacket_ep(struct usb_device *dev, int if_idx, int ep_idx)
291 {
292 	int b;
293 	struct usb_endpoint_descriptor *ep;
294 	u16 ep_wMaxPacketSize;
295 
296 	ep = &dev->config.if_desc[if_idx].ep_desc[ep_idx];
297 
298 	b = ep->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
299 	ep_wMaxPacketSize = get_unaligned(&ep->wMaxPacketSize);
300 
301 	if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
302 						USB_ENDPOINT_XFER_CONTROL) {
303 		/* Control => bidirectional */
304 		dev->epmaxpacketout[b] = ep_wMaxPacketSize;
305 		dev->epmaxpacketin[b] = ep_wMaxPacketSize;
306 		debug("##Control EP epmaxpacketout/in[%d] = %d\n",
307 		      b, dev->epmaxpacketin[b]);
308 	} else {
309 		if ((ep->bEndpointAddress & 0x80) == 0) {
310 			/* OUT Endpoint */
311 			if (ep_wMaxPacketSize > dev->epmaxpacketout[b]) {
312 				dev->epmaxpacketout[b] = ep_wMaxPacketSize;
313 				debug("##EP epmaxpacketout[%d] = %d\n",
314 				      b, dev->epmaxpacketout[b]);
315 			}
316 		} else {
317 			/* IN Endpoint */
318 			if (ep_wMaxPacketSize > dev->epmaxpacketin[b]) {
319 				dev->epmaxpacketin[b] = ep_wMaxPacketSize;
320 				debug("##EP epmaxpacketin[%d] = %d\n",
321 				      b, dev->epmaxpacketin[b]);
322 			}
323 		} /* if out */
324 	} /* if control */
325 }
326 
327 /*
328  * set the max packed value of all endpoints in the given configuration
329  */
330 static int usb_set_maxpacket(struct usb_device *dev)
331 {
332 	int i, ii;
333 
334 	for (i = 0; i < dev->config.desc.bNumInterfaces; i++)
335 		for (ii = 0; ii < dev->config.if_desc[i].desc.bNumEndpoints; ii++)
336 			usb_set_maxpacket_ep(dev, i, ii);
337 
338 	return 0;
339 }
340 
341 /*******************************************************************************
342  * Parse the config, located in buffer, and fills the dev->config structure.
343  * Note that all little/big endian swapping are done automatically.
344  */
345 static int usb_parse_config(struct usb_device *dev,
346 			unsigned char *buffer, int cfgno)
347 {
348 	struct usb_descriptor_header *head;
349 	int index, ifno, epno, curr_if_num;
350 	u16 ep_wMaxPacketSize;
351 	struct usb_interface *if_desc = NULL;
352 
353 	ifno = -1;
354 	epno = -1;
355 	curr_if_num = -1;
356 
357 	dev->configno = cfgno;
358 	head = (struct usb_descriptor_header *) &buffer[0];
359 	if (head->bDescriptorType != USB_DT_CONFIG) {
360 		printf(" ERROR: NOT USB_CONFIG_DESC %x\n",
361 			head->bDescriptorType);
362 		return -1;
363 	}
364 	memcpy(&dev->config, buffer, buffer[0]);
365 	le16_to_cpus(&(dev->config.desc.wTotalLength));
366 	dev->config.no_of_if = 0;
367 
368 	index = dev->config.desc.bLength;
369 	/* Ok the first entry must be a configuration entry,
370 	 * now process the others */
371 	head = (struct usb_descriptor_header *) &buffer[index];
372 	while (index + 1 < dev->config.desc.wTotalLength) {
373 		switch (head->bDescriptorType) {
374 		case USB_DT_INTERFACE:
375 			if (((struct usb_interface_descriptor *) \
376 			     &buffer[index])->bInterfaceNumber != curr_if_num) {
377 				/* this is a new interface, copy new desc */
378 				ifno = dev->config.no_of_if;
379 				if_desc = &dev->config.if_desc[ifno];
380 				dev->config.no_of_if++;
381 				memcpy(if_desc,	&buffer[index], buffer[index]);
382 				if_desc->no_of_ep = 0;
383 				if_desc->num_altsetting = 1;
384 				curr_if_num =
385 				     if_desc->desc.bInterfaceNumber;
386 			} else {
387 				/* found alternate setting for the interface */
388 				if (ifno >= 0) {
389 					if_desc = &dev->config.if_desc[ifno];
390 					if_desc->num_altsetting++;
391 				}
392 			}
393 			break;
394 		case USB_DT_ENDPOINT:
395 			epno = dev->config.if_desc[ifno].no_of_ep;
396 			if_desc = &dev->config.if_desc[ifno];
397 			/* found an endpoint */
398 			if_desc->no_of_ep++;
399 			memcpy(&if_desc->ep_desc[epno],
400 				&buffer[index], buffer[index]);
401 			ep_wMaxPacketSize = get_unaligned(&dev->config.\
402 							if_desc[ifno].\
403 							ep_desc[epno].\
404 							wMaxPacketSize);
405 			put_unaligned(le16_to_cpu(ep_wMaxPacketSize),
406 					&dev->config.\
407 					if_desc[ifno].\
408 					ep_desc[epno].\
409 					wMaxPacketSize);
410 			debug("if %d, ep %d\n", ifno, epno);
411 			break;
412 		default:
413 			if (head->bLength == 0)
414 				return 1;
415 
416 			debug("unknown Description Type : %x\n",
417 			      head->bDescriptorType);
418 
419 #ifdef DEBUG
420 			{
421 				unsigned char *ch = (unsigned char *)head;
422 				int i;
423 
424 				for (i = 0; i < head->bLength; i++)
425 					debug("%02X ", *ch++);
426 				debug("\n\n\n");
427 			}
428 #endif
429 			break;
430 		}
431 		index += head->bLength;
432 		head = (struct usb_descriptor_header *)&buffer[index];
433 	}
434 	return 1;
435 }
436 
437 /***********************************************************************
438  * Clears an endpoint
439  * endp: endpoint number in bits 0-3;
440  * direction flag in bit 7 (1 = IN, 0 = OUT)
441  */
442 int usb_clear_halt(struct usb_device *dev, int pipe)
443 {
444 	int result;
445 	int endp = usb_pipeendpoint(pipe)|(usb_pipein(pipe)<<7);
446 
447 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
448 				 USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT, 0,
449 				 endp, NULL, 0, USB_CNTL_TIMEOUT * 3);
450 
451 	/* don't clear if failed */
452 	if (result < 0)
453 		return result;
454 
455 	/*
456 	 * NOTE: we do not get status and verify reset was successful
457 	 * as some devices are reported to lock up upon this check..
458 	 */
459 
460 	usb_endpoint_running(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe));
461 
462 	/* toggle is reset on clear */
463 	usb_settoggle(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe), 0);
464 	return 0;
465 }
466 
467 
468 /**********************************************************************
469  * get_descriptor type
470  */
471 static int usb_get_descriptor(struct usb_device *dev, unsigned char type,
472 			unsigned char index, void *buf, int size)
473 {
474 	int res;
475 	res = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
476 			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
477 			(type << 8) + index, 0,
478 			buf, size, USB_CNTL_TIMEOUT);
479 	return res;
480 }
481 
482 /**********************************************************************
483  * gets configuration cfgno and store it in the buffer
484  */
485 int usb_get_configuration_no(struct usb_device *dev,
486 			     unsigned char *buffer, int cfgno)
487 {
488 	int result;
489 	unsigned int tmp;
490 	struct usb_config_descriptor *config;
491 
492 	config = (struct usb_config_descriptor *)&buffer[0];
493 	result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno, buffer, 9);
494 	if (result < 9) {
495 		if (result < 0)
496 			printf("unable to get descriptor, error %lX\n",
497 				dev->status);
498 		else
499 			printf("config descriptor too short " \
500 				"(expected %i, got %i)\n", 9, result);
501 		return -1;
502 	}
503 	tmp = le16_to_cpu(config->wTotalLength);
504 
505 	if (tmp > USB_BUFSIZ) {
506 		printf("usb_get_configuration_no: failed to get " \
507 		       "descriptor - too long: %d\n", tmp);
508 		return -1;
509 	}
510 
511 	result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno, buffer, tmp);
512 	debug("get_conf_no %d Result %d, wLength %d\n", cfgno, result, tmp);
513 	return result;
514 }
515 
516 /********************************************************************
517  * set address of a device to the value in dev->devnum.
518  * This can only be done by addressing the device via the default address (0)
519  */
520 static int usb_set_address(struct usb_device *dev)
521 {
522 	int res;
523 
524 	debug("set address %d\n", dev->devnum);
525 	res = usb_control_msg(dev, usb_snddefctrl(dev),
526 				USB_REQ_SET_ADDRESS, 0,
527 				(dev->devnum), 0,
528 				NULL, 0, USB_CNTL_TIMEOUT);
529 	return res;
530 }
531 
532 /********************************************************************
533  * set interface number to interface
534  */
535 int usb_set_interface(struct usb_device *dev, int interface, int alternate)
536 {
537 	struct usb_interface *if_face = NULL;
538 	int ret, i;
539 
540 	for (i = 0; i < dev->config.desc.bNumInterfaces; i++) {
541 		if (dev->config.if_desc[i].desc.bInterfaceNumber == interface) {
542 			if_face = &dev->config.if_desc[i];
543 			break;
544 		}
545 	}
546 	if (!if_face) {
547 		printf("selecting invalid interface %d", interface);
548 		return -1;
549 	}
550 	/*
551 	 * We should return now for devices with only one alternate setting.
552 	 * According to 9.4.10 of the Universal Serial Bus Specification
553 	 * Revision 2.0 such devices can return with a STALL. This results in
554 	 * some USB sticks timeouting during initialization and then being
555 	 * unusable in U-Boot.
556 	 */
557 	if (if_face->num_altsetting == 1)
558 		return 0;
559 
560 	ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
561 				USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE,
562 				alternate, interface, NULL, 0,
563 				USB_CNTL_TIMEOUT * 5);
564 	if (ret < 0)
565 		return ret;
566 
567 	return 0;
568 }
569 
570 /********************************************************************
571  * set configuration number to configuration
572  */
573 static int usb_set_configuration(struct usb_device *dev, int configuration)
574 {
575 	int res;
576 	debug("set configuration %d\n", configuration);
577 	/* set setup command */
578 	res = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
579 				USB_REQ_SET_CONFIGURATION, 0,
580 				configuration, 0,
581 				NULL, 0, USB_CNTL_TIMEOUT);
582 	if (res == 0) {
583 		dev->toggle[0] = 0;
584 		dev->toggle[1] = 0;
585 		return 0;
586 	} else
587 		return -1;
588 }
589 
590 /********************************************************************
591  * set protocol to protocol
592  */
593 int usb_set_protocol(struct usb_device *dev, int ifnum, int protocol)
594 {
595 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
596 		USB_REQ_SET_PROTOCOL, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
597 		protocol, ifnum, NULL, 0, USB_CNTL_TIMEOUT);
598 }
599 
600 /********************************************************************
601  * set idle
602  */
603 int usb_set_idle(struct usb_device *dev, int ifnum, int duration, int report_id)
604 {
605 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
606 		USB_REQ_SET_IDLE, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
607 		(duration << 8) | report_id, ifnum, NULL, 0, USB_CNTL_TIMEOUT);
608 }
609 
610 /********************************************************************
611  * get report
612  */
613 int usb_get_report(struct usb_device *dev, int ifnum, unsigned char type,
614 		   unsigned char id, void *buf, int size)
615 {
616 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
617 			USB_REQ_GET_REPORT,
618 			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
619 			(type << 8) + id, ifnum, buf, size, USB_CNTL_TIMEOUT);
620 }
621 
622 /********************************************************************
623  * get class descriptor
624  */
625 int usb_get_class_descriptor(struct usb_device *dev, int ifnum,
626 		unsigned char type, unsigned char id, void *buf, int size)
627 {
628 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
629 		USB_REQ_GET_DESCRIPTOR, USB_RECIP_INTERFACE | USB_DIR_IN,
630 		(type << 8) + id, ifnum, buf, size, USB_CNTL_TIMEOUT);
631 }
632 
633 /********************************************************************
634  * get string index in buffer
635  */
636 static int usb_get_string(struct usb_device *dev, unsigned short langid,
637 		   unsigned char index, void *buf, int size)
638 {
639 	int i;
640 	int result;
641 
642 	for (i = 0; i < 3; ++i) {
643 		/* some devices are flaky */
644 		result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
645 			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
646 			(USB_DT_STRING << 8) + index, langid, buf, size,
647 			USB_CNTL_TIMEOUT);
648 
649 		if (result > 0)
650 			break;
651 	}
652 
653 	return result;
654 }
655 
656 
657 static void usb_try_string_workarounds(unsigned char *buf, int *length)
658 {
659 	int newlength, oldlength = *length;
660 
661 	for (newlength = 2; newlength + 1 < oldlength; newlength += 2)
662 		if (!isprint(buf[newlength]) || buf[newlength + 1])
663 			break;
664 
665 	if (newlength > 2) {
666 		buf[0] = newlength;
667 		*length = newlength;
668 	}
669 }
670 
671 
672 static int usb_string_sub(struct usb_device *dev, unsigned int langid,
673 		unsigned int index, unsigned char *buf)
674 {
675 	int rc;
676 
677 	/* Try to read the string descriptor by asking for the maximum
678 	 * possible number of bytes */
679 	rc = usb_get_string(dev, langid, index, buf, 255);
680 
681 	/* If that failed try to read the descriptor length, then
682 	 * ask for just that many bytes */
683 	if (rc < 2) {
684 		rc = usb_get_string(dev, langid, index, buf, 2);
685 		if (rc == 2)
686 			rc = usb_get_string(dev, langid, index, buf, buf[0]);
687 	}
688 
689 	if (rc >= 2) {
690 		if (!buf[0] && !buf[1])
691 			usb_try_string_workarounds(buf, &rc);
692 
693 		/* There might be extra junk at the end of the descriptor */
694 		if (buf[0] < rc)
695 			rc = buf[0];
696 
697 		rc = rc - (rc & 1); /* force a multiple of two */
698 	}
699 
700 	if (rc < 2)
701 		rc = -1;
702 
703 	return rc;
704 }
705 
706 
707 /********************************************************************
708  * usb_string:
709  * Get string index and translate it to ascii.
710  * returns string length (> 0) or error (< 0)
711  */
712 int usb_string(struct usb_device *dev, int index, char *buf, size_t size)
713 {
714 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, mybuf, USB_BUFSIZ);
715 	unsigned char *tbuf;
716 	int err;
717 	unsigned int u, idx;
718 
719 	if (size <= 0 || !buf || !index)
720 		return -1;
721 	buf[0] = 0;
722 	tbuf = &mybuf[0];
723 
724 	/* get langid for strings if it's not yet known */
725 	if (!dev->have_langid) {
726 		err = usb_string_sub(dev, 0, 0, tbuf);
727 		if (err < 0) {
728 			debug("error getting string descriptor 0 " \
729 			      "(error=%lx)\n", dev->status);
730 			return -1;
731 		} else if (tbuf[0] < 4) {
732 			debug("string descriptor 0 too short\n");
733 			return -1;
734 		} else {
735 			dev->have_langid = -1;
736 			dev->string_langid = tbuf[2] | (tbuf[3] << 8);
737 				/* always use the first langid listed */
738 			debug("USB device number %d default " \
739 			      "language ID 0x%x\n",
740 			      dev->devnum, dev->string_langid);
741 		}
742 	}
743 
744 	err = usb_string_sub(dev, dev->string_langid, index, tbuf);
745 	if (err < 0)
746 		return err;
747 
748 	size--;		/* leave room for trailing NULL char in output buffer */
749 	for (idx = 0, u = 2; u < err; u += 2) {
750 		if (idx >= size)
751 			break;
752 		if (tbuf[u+1])			/* high byte */
753 			buf[idx++] = '?';  /* non-ASCII character */
754 		else
755 			buf[idx++] = tbuf[u];
756 	}
757 	buf[idx] = 0;
758 	err = idx;
759 	return err;
760 }
761 
762 
763 /********************************************************************
764  * USB device handling:
765  * the USB device are static allocated [USB_MAX_DEVICE].
766  */
767 
768 
769 /* returns a pointer to the device with the index [index].
770  * if the device is not assigned (dev->devnum==-1) returns NULL
771  */
772 struct usb_device *usb_get_dev_index(int index)
773 {
774 	if (usb_dev[index].devnum == -1)
775 		return NULL;
776 	else
777 		return &usb_dev[index];
778 }
779 
780 /* returns a pointer of a new device structure or NULL, if
781  * no device struct is available
782  */
783 struct usb_device *usb_alloc_new_device(void *controller)
784 {
785 	int i;
786 	debug("New Device %d\n", dev_index);
787 	if (dev_index == USB_MAX_DEVICE) {
788 		printf("ERROR, too many USB Devices, max=%d\n", USB_MAX_DEVICE);
789 		return NULL;
790 	}
791 	/* default Address is 0, real addresses start with 1 */
792 	usb_dev[dev_index].devnum = dev_index + 1;
793 	usb_dev[dev_index].maxchild = 0;
794 	for (i = 0; i < USB_MAXCHILDREN; i++)
795 		usb_dev[dev_index].children[i] = NULL;
796 	usb_dev[dev_index].parent = NULL;
797 	usb_dev[dev_index].controller = controller;
798 	dev_index++;
799 	return &usb_dev[dev_index - 1];
800 }
801 
802 /*
803  * Free the newly created device node.
804  * Called in error cases where configuring a newly attached
805  * device fails for some reason.
806  */
807 void usb_free_device(void)
808 {
809 	dev_index--;
810 	debug("Freeing device node: %d\n", dev_index);
811 	memset(&usb_dev[dev_index], 0, sizeof(struct usb_device));
812 	usb_dev[dev_index].devnum = -1;
813 }
814 
815 /*
816  * By the time we get here, the device has gotten a new device ID
817  * and is in the default state. We need to identify the thing and
818  * get the ball rolling..
819  *
820  * Returns 0 for success, != 0 for error.
821  */
822 int usb_new_device(struct usb_device *dev)
823 {
824 	int addr, err;
825 	int tmp;
826 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, tmpbuf, USB_BUFSIZ);
827 
828 	/* We still haven't set the Address yet */
829 	addr = dev->devnum;
830 	dev->devnum = 0;
831 
832 #ifdef CONFIG_LEGACY_USB_INIT_SEQ
833 	/* this is the old and known way of initializing devices, it is
834 	 * different than what Windows and Linux are doing. Windows and Linux
835 	 * both retrieve 64 bytes while reading the device descriptor
836 	 * Several USB stick devices report ERR: CTL_TIMEOUT, caused by an
837 	 * invalid header while reading 8 bytes as device descriptor. */
838 	dev->descriptor.bMaxPacketSize0 = 8;	    /* Start off at 8 bytes  */
839 	dev->maxpacketsize = PACKET_SIZE_8;
840 	dev->epmaxpacketin[0] = 8;
841 	dev->epmaxpacketout[0] = 8;
842 
843 	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0, tmpbuf, 8);
844 	if (err < 8) {
845 		printf("\n      USB device not responding, " \
846 		       "giving up (status=%lX)\n", dev->status);
847 		return 1;
848 	}
849 	memcpy(&dev->descriptor, tmpbuf, 8);
850 #else
851 	/* This is a Windows scheme of initialization sequence, with double
852 	 * reset of the device (Linux uses the same sequence)
853 	 * Some equipment is said to work only with such init sequence; this
854 	 * patch is based on the work by Alan Stern:
855 	 * http://sourceforge.net/mailarchive/forum.php?
856 	 * thread_id=5729457&forum_id=5398
857 	 */
858 	struct usb_device_descriptor *desc;
859 	int port = -1;
860 	struct usb_device *parent = dev->parent;
861 	unsigned short portstatus;
862 
863 	/* send 64-byte GET-DEVICE-DESCRIPTOR request.  Since the descriptor is
864 	 * only 18 bytes long, this will terminate with a short packet.  But if
865 	 * the maxpacket size is 8 or 16 the device may be waiting to transmit
866 	 * some more, or keeps on retransmitting the 8 byte header. */
867 
868 	desc = (struct usb_device_descriptor *)tmpbuf;
869 	dev->descriptor.bMaxPacketSize0 = 64;	    /* Start off at 64 bytes  */
870 	/* Default to 64 byte max packet size */
871 	dev->maxpacketsize = PACKET_SIZE_64;
872 	dev->epmaxpacketin[0] = 64;
873 	dev->epmaxpacketout[0] = 64;
874 
875 	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, 64);
876 	if (err < 0) {
877 		debug("usb_new_device: usb_get_descriptor() failed\n");
878 		return 1;
879 	}
880 
881 	dev->descriptor.bMaxPacketSize0 = desc->bMaxPacketSize0;
882 
883 	/* find the port number we're at */
884 	if (parent) {
885 		int j;
886 
887 		for (j = 0; j < parent->maxchild; j++) {
888 			if (parent->children[j] == dev) {
889 				port = j;
890 				break;
891 			}
892 		}
893 		if (port < 0) {
894 			printf("usb_new_device:cannot locate device's port.\n");
895 			return 1;
896 		}
897 
898 		/* reset the port for the second time */
899 		err = hub_port_reset(dev->parent, port, &portstatus);
900 		if (err < 0) {
901 			printf("\n     Couldn't reset port %i\n", port);
902 			return 1;
903 		}
904 	}
905 #endif
906 
907 	dev->epmaxpacketin[0] = dev->descriptor.bMaxPacketSize0;
908 	dev->epmaxpacketout[0] = dev->descriptor.bMaxPacketSize0;
909 	switch (dev->descriptor.bMaxPacketSize0) {
910 	case 8:
911 		dev->maxpacketsize  = PACKET_SIZE_8;
912 		break;
913 	case 16:
914 		dev->maxpacketsize = PACKET_SIZE_16;
915 		break;
916 	case 32:
917 		dev->maxpacketsize = PACKET_SIZE_32;
918 		break;
919 	case 64:
920 		dev->maxpacketsize = PACKET_SIZE_64;
921 		break;
922 	}
923 	dev->devnum = addr;
924 
925 	err = usb_set_address(dev); /* set address */
926 
927 	if (err < 0) {
928 		printf("\n      USB device not accepting new address " \
929 			"(error=%lX)\n", dev->status);
930 		return 1;
931 	}
932 
933 	mdelay(10);	/* Let the SET_ADDRESS settle */
934 
935 	tmp = sizeof(dev->descriptor);
936 
937 	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0,
938 				 tmpbuf, sizeof(dev->descriptor));
939 	if (err < tmp) {
940 		if (err < 0)
941 			printf("unable to get device descriptor (error=%d)\n",
942 			       err);
943 		else
944 			printf("USB device descriptor short read " \
945 				"(expected %i, got %i)\n", tmp, err);
946 		return 1;
947 	}
948 	memcpy(&dev->descriptor, tmpbuf, sizeof(dev->descriptor));
949 	/* correct le values */
950 	le16_to_cpus(&dev->descriptor.bcdUSB);
951 	le16_to_cpus(&dev->descriptor.idVendor);
952 	le16_to_cpus(&dev->descriptor.idProduct);
953 	le16_to_cpus(&dev->descriptor.bcdDevice);
954 	/* only support for one config for now */
955 	err = usb_get_configuration_no(dev, tmpbuf, 0);
956 	if (err < 0) {
957 		printf("usb_new_device: Cannot read configuration, " \
958 		       "skipping device %04x:%04x\n",
959 		       dev->descriptor.idVendor, dev->descriptor.idProduct);
960 		return -1;
961 	}
962 	usb_parse_config(dev, tmpbuf, 0);
963 	usb_set_maxpacket(dev);
964 	/* we set the default configuration here */
965 	if (usb_set_configuration(dev, dev->config.desc.bConfigurationValue)) {
966 		printf("failed to set default configuration " \
967 			"len %d, status %lX\n", dev->act_len, dev->status);
968 		return -1;
969 	}
970 	debug("new device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
971 	      dev->descriptor.iManufacturer, dev->descriptor.iProduct,
972 	      dev->descriptor.iSerialNumber);
973 	memset(dev->mf, 0, sizeof(dev->mf));
974 	memset(dev->prod, 0, sizeof(dev->prod));
975 	memset(dev->serial, 0, sizeof(dev->serial));
976 	if (dev->descriptor.iManufacturer)
977 		usb_string(dev, dev->descriptor.iManufacturer,
978 			   dev->mf, sizeof(dev->mf));
979 	if (dev->descriptor.iProduct)
980 		usb_string(dev, dev->descriptor.iProduct,
981 			   dev->prod, sizeof(dev->prod));
982 	if (dev->descriptor.iSerialNumber)
983 		usb_string(dev, dev->descriptor.iSerialNumber,
984 			   dev->serial, sizeof(dev->serial));
985 	debug("Manufacturer %s\n", dev->mf);
986 	debug("Product      %s\n", dev->prod);
987 	debug("SerialNumber %s\n", dev->serial);
988 	/* now prode if the device is a hub */
989 	usb_hub_probe(dev, 0);
990 	return 0;
991 }
992 
993 /* EOF */
994