xref: /openbmc/u-boot/common/usb.c (revision 983c72f4)
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 		case USB_DT_SS_ENDPOINT_COMP:
413 			if_desc = &dev->config.if_desc[ifno];
414 			memcpy(&if_desc->ss_ep_comp_desc[epno],
415 				&buffer[index], buffer[index]);
416 			break;
417 		default:
418 			if (head->bLength == 0)
419 				return 1;
420 
421 			debug("unknown Description Type : %x\n",
422 			      head->bDescriptorType);
423 
424 #ifdef DEBUG
425 			{
426 				unsigned char *ch = (unsigned char *)head;
427 				int i;
428 
429 				for (i = 0; i < head->bLength; i++)
430 					debug("%02X ", *ch++);
431 				debug("\n\n\n");
432 			}
433 #endif
434 			break;
435 		}
436 		index += head->bLength;
437 		head = (struct usb_descriptor_header *)&buffer[index];
438 	}
439 	return 1;
440 }
441 
442 /***********************************************************************
443  * Clears an endpoint
444  * endp: endpoint number in bits 0-3;
445  * direction flag in bit 7 (1 = IN, 0 = OUT)
446  */
447 int usb_clear_halt(struct usb_device *dev, int pipe)
448 {
449 	int result;
450 	int endp = usb_pipeendpoint(pipe)|(usb_pipein(pipe)<<7);
451 
452 	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
453 				 USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT, 0,
454 				 endp, NULL, 0, USB_CNTL_TIMEOUT * 3);
455 
456 	/* don't clear if failed */
457 	if (result < 0)
458 		return result;
459 
460 	/*
461 	 * NOTE: we do not get status and verify reset was successful
462 	 * as some devices are reported to lock up upon this check..
463 	 */
464 
465 	usb_endpoint_running(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe));
466 
467 	/* toggle is reset on clear */
468 	usb_settoggle(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe), 0);
469 	return 0;
470 }
471 
472 
473 /**********************************************************************
474  * get_descriptor type
475  */
476 static int usb_get_descriptor(struct usb_device *dev, unsigned char type,
477 			unsigned char index, void *buf, int size)
478 {
479 	int res;
480 	res = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
481 			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
482 			(type << 8) + index, 0,
483 			buf, size, USB_CNTL_TIMEOUT);
484 	return res;
485 }
486 
487 /**********************************************************************
488  * gets configuration cfgno and store it in the buffer
489  */
490 int usb_get_configuration_no(struct usb_device *dev,
491 			     unsigned char *buffer, int cfgno)
492 {
493 	int result;
494 	unsigned int tmp;
495 	struct usb_config_descriptor *config;
496 
497 	config = (struct usb_config_descriptor *)&buffer[0];
498 	result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno, buffer, 9);
499 	if (result < 9) {
500 		if (result < 0)
501 			printf("unable to get descriptor, error %lX\n",
502 				dev->status);
503 		else
504 			printf("config descriptor too short " \
505 				"(expected %i, got %i)\n", 9, result);
506 		return -1;
507 	}
508 	tmp = le16_to_cpu(config->wTotalLength);
509 
510 	if (tmp > USB_BUFSIZ) {
511 		printf("usb_get_configuration_no: failed to get " \
512 		       "descriptor - too long: %d\n", tmp);
513 		return -1;
514 	}
515 
516 	result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno, buffer, tmp);
517 	debug("get_conf_no %d Result %d, wLength %d\n", cfgno, result, tmp);
518 	return result;
519 }
520 
521 /********************************************************************
522  * set address of a device to the value in dev->devnum.
523  * This can only be done by addressing the device via the default address (0)
524  */
525 static int usb_set_address(struct usb_device *dev)
526 {
527 	int res;
528 
529 	debug("set address %d\n", dev->devnum);
530 	res = usb_control_msg(dev, usb_snddefctrl(dev),
531 				USB_REQ_SET_ADDRESS, 0,
532 				(dev->devnum), 0,
533 				NULL, 0, USB_CNTL_TIMEOUT);
534 	return res;
535 }
536 
537 /********************************************************************
538  * set interface number to interface
539  */
540 int usb_set_interface(struct usb_device *dev, int interface, int alternate)
541 {
542 	struct usb_interface *if_face = NULL;
543 	int ret, i;
544 
545 	for (i = 0; i < dev->config.desc.bNumInterfaces; i++) {
546 		if (dev->config.if_desc[i].desc.bInterfaceNumber == interface) {
547 			if_face = &dev->config.if_desc[i];
548 			break;
549 		}
550 	}
551 	if (!if_face) {
552 		printf("selecting invalid interface %d", interface);
553 		return -1;
554 	}
555 	/*
556 	 * We should return now for devices with only one alternate setting.
557 	 * According to 9.4.10 of the Universal Serial Bus Specification
558 	 * Revision 2.0 such devices can return with a STALL. This results in
559 	 * some USB sticks timeouting during initialization and then being
560 	 * unusable in U-Boot.
561 	 */
562 	if (if_face->num_altsetting == 1)
563 		return 0;
564 
565 	ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
566 				USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE,
567 				alternate, interface, NULL, 0,
568 				USB_CNTL_TIMEOUT * 5);
569 	if (ret < 0)
570 		return ret;
571 
572 	return 0;
573 }
574 
575 /********************************************************************
576  * set configuration number to configuration
577  */
578 static int usb_set_configuration(struct usb_device *dev, int configuration)
579 {
580 	int res;
581 	debug("set configuration %d\n", configuration);
582 	/* set setup command */
583 	res = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
584 				USB_REQ_SET_CONFIGURATION, 0,
585 				configuration, 0,
586 				NULL, 0, USB_CNTL_TIMEOUT);
587 	if (res == 0) {
588 		dev->toggle[0] = 0;
589 		dev->toggle[1] = 0;
590 		return 0;
591 	} else
592 		return -1;
593 }
594 
595 /********************************************************************
596  * set protocol to protocol
597  */
598 int usb_set_protocol(struct usb_device *dev, int ifnum, int protocol)
599 {
600 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
601 		USB_REQ_SET_PROTOCOL, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
602 		protocol, ifnum, NULL, 0, USB_CNTL_TIMEOUT);
603 }
604 
605 /********************************************************************
606  * set idle
607  */
608 int usb_set_idle(struct usb_device *dev, int ifnum, int duration, int report_id)
609 {
610 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
611 		USB_REQ_SET_IDLE, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
612 		(duration << 8) | report_id, ifnum, NULL, 0, USB_CNTL_TIMEOUT);
613 }
614 
615 /********************************************************************
616  * get report
617  */
618 int usb_get_report(struct usb_device *dev, int ifnum, unsigned char type,
619 		   unsigned char id, void *buf, int size)
620 {
621 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
622 			USB_REQ_GET_REPORT,
623 			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
624 			(type << 8) + id, ifnum, buf, size, USB_CNTL_TIMEOUT);
625 }
626 
627 /********************************************************************
628  * get class descriptor
629  */
630 int usb_get_class_descriptor(struct usb_device *dev, int ifnum,
631 		unsigned char type, unsigned char id, void *buf, int size)
632 {
633 	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
634 		USB_REQ_GET_DESCRIPTOR, USB_RECIP_INTERFACE | USB_DIR_IN,
635 		(type << 8) + id, ifnum, buf, size, USB_CNTL_TIMEOUT);
636 }
637 
638 /********************************************************************
639  * get string index in buffer
640  */
641 static int usb_get_string(struct usb_device *dev, unsigned short langid,
642 		   unsigned char index, void *buf, int size)
643 {
644 	int i;
645 	int result;
646 
647 	for (i = 0; i < 3; ++i) {
648 		/* some devices are flaky */
649 		result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
650 			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
651 			(USB_DT_STRING << 8) + index, langid, buf, size,
652 			USB_CNTL_TIMEOUT);
653 
654 		if (result > 0)
655 			break;
656 	}
657 
658 	return result;
659 }
660 
661 
662 static void usb_try_string_workarounds(unsigned char *buf, int *length)
663 {
664 	int newlength, oldlength = *length;
665 
666 	for (newlength = 2; newlength + 1 < oldlength; newlength += 2)
667 		if (!isprint(buf[newlength]) || buf[newlength + 1])
668 			break;
669 
670 	if (newlength > 2) {
671 		buf[0] = newlength;
672 		*length = newlength;
673 	}
674 }
675 
676 
677 static int usb_string_sub(struct usb_device *dev, unsigned int langid,
678 		unsigned int index, unsigned char *buf)
679 {
680 	int rc;
681 
682 	/* Try to read the string descriptor by asking for the maximum
683 	 * possible number of bytes */
684 	rc = usb_get_string(dev, langid, index, buf, 255);
685 
686 	/* If that failed try to read the descriptor length, then
687 	 * ask for just that many bytes */
688 	if (rc < 2) {
689 		rc = usb_get_string(dev, langid, index, buf, 2);
690 		if (rc == 2)
691 			rc = usb_get_string(dev, langid, index, buf, buf[0]);
692 	}
693 
694 	if (rc >= 2) {
695 		if (!buf[0] && !buf[1])
696 			usb_try_string_workarounds(buf, &rc);
697 
698 		/* There might be extra junk at the end of the descriptor */
699 		if (buf[0] < rc)
700 			rc = buf[0];
701 
702 		rc = rc - (rc & 1); /* force a multiple of two */
703 	}
704 
705 	if (rc < 2)
706 		rc = -1;
707 
708 	return rc;
709 }
710 
711 
712 /********************************************************************
713  * usb_string:
714  * Get string index and translate it to ascii.
715  * returns string length (> 0) or error (< 0)
716  */
717 int usb_string(struct usb_device *dev, int index, char *buf, size_t size)
718 {
719 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, mybuf, USB_BUFSIZ);
720 	unsigned char *tbuf;
721 	int err;
722 	unsigned int u, idx;
723 
724 	if (size <= 0 || !buf || !index)
725 		return -1;
726 	buf[0] = 0;
727 	tbuf = &mybuf[0];
728 
729 	/* get langid for strings if it's not yet known */
730 	if (!dev->have_langid) {
731 		err = usb_string_sub(dev, 0, 0, tbuf);
732 		if (err < 0) {
733 			debug("error getting string descriptor 0 " \
734 			      "(error=%lx)\n", dev->status);
735 			return -1;
736 		} else if (tbuf[0] < 4) {
737 			debug("string descriptor 0 too short\n");
738 			return -1;
739 		} else {
740 			dev->have_langid = -1;
741 			dev->string_langid = tbuf[2] | (tbuf[3] << 8);
742 				/* always use the first langid listed */
743 			debug("USB device number %d default " \
744 			      "language ID 0x%x\n",
745 			      dev->devnum, dev->string_langid);
746 		}
747 	}
748 
749 	err = usb_string_sub(dev, dev->string_langid, index, tbuf);
750 	if (err < 0)
751 		return err;
752 
753 	size--;		/* leave room for trailing NULL char in output buffer */
754 	for (idx = 0, u = 2; u < err; u += 2) {
755 		if (idx >= size)
756 			break;
757 		if (tbuf[u+1])			/* high byte */
758 			buf[idx++] = '?';  /* non-ASCII character */
759 		else
760 			buf[idx++] = tbuf[u];
761 	}
762 	buf[idx] = 0;
763 	err = idx;
764 	return err;
765 }
766 
767 
768 /********************************************************************
769  * USB device handling:
770  * the USB device are static allocated [USB_MAX_DEVICE].
771  */
772 
773 
774 /* returns a pointer to the device with the index [index].
775  * if the device is not assigned (dev->devnum==-1) returns NULL
776  */
777 struct usb_device *usb_get_dev_index(int index)
778 {
779 	if (usb_dev[index].devnum == -1)
780 		return NULL;
781 	else
782 		return &usb_dev[index];
783 }
784 
785 /* returns a pointer of a new device structure or NULL, if
786  * no device struct is available
787  */
788 struct usb_device *usb_alloc_new_device(void *controller)
789 {
790 	int i;
791 	debug("New Device %d\n", dev_index);
792 	if (dev_index == USB_MAX_DEVICE) {
793 		printf("ERROR, too many USB Devices, max=%d\n", USB_MAX_DEVICE);
794 		return NULL;
795 	}
796 	/* default Address is 0, real addresses start with 1 */
797 	usb_dev[dev_index].devnum = dev_index + 1;
798 	usb_dev[dev_index].maxchild = 0;
799 	for (i = 0; i < USB_MAXCHILDREN; i++)
800 		usb_dev[dev_index].children[i] = NULL;
801 	usb_dev[dev_index].parent = NULL;
802 	usb_dev[dev_index].controller = controller;
803 	dev_index++;
804 	return &usb_dev[dev_index - 1];
805 }
806 
807 /*
808  * Free the newly created device node.
809  * Called in error cases where configuring a newly attached
810  * device fails for some reason.
811  */
812 void usb_free_device(void)
813 {
814 	dev_index--;
815 	debug("Freeing device node: %d\n", dev_index);
816 	memset(&usb_dev[dev_index], 0, sizeof(struct usb_device));
817 	usb_dev[dev_index].devnum = -1;
818 }
819 
820 /*
821  * By the time we get here, the device has gotten a new device ID
822  * and is in the default state. We need to identify the thing and
823  * get the ball rolling..
824  *
825  * Returns 0 for success, != 0 for error.
826  */
827 int usb_new_device(struct usb_device *dev)
828 {
829 	int addr, err;
830 	int tmp;
831 	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, tmpbuf, USB_BUFSIZ);
832 
833 	/* We still haven't set the Address yet */
834 	addr = dev->devnum;
835 	dev->devnum = 0;
836 
837 #ifdef CONFIG_LEGACY_USB_INIT_SEQ
838 	/* this is the old and known way of initializing devices, it is
839 	 * different than what Windows and Linux are doing. Windows and Linux
840 	 * both retrieve 64 bytes while reading the device descriptor
841 	 * Several USB stick devices report ERR: CTL_TIMEOUT, caused by an
842 	 * invalid header while reading 8 bytes as device descriptor. */
843 	dev->descriptor.bMaxPacketSize0 = 8;	    /* Start off at 8 bytes  */
844 	dev->maxpacketsize = PACKET_SIZE_8;
845 	dev->epmaxpacketin[0] = 8;
846 	dev->epmaxpacketout[0] = 8;
847 
848 	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0, tmpbuf, 8);
849 	if (err < 8) {
850 		printf("\n      USB device not responding, " \
851 		       "giving up (status=%lX)\n", dev->status);
852 		return 1;
853 	}
854 	memcpy(&dev->descriptor, tmpbuf, 8);
855 #else
856 	/* This is a Windows scheme of initialization sequence, with double
857 	 * reset of the device (Linux uses the same sequence)
858 	 * Some equipment is said to work only with such init sequence; this
859 	 * patch is based on the work by Alan Stern:
860 	 * http://sourceforge.net/mailarchive/forum.php?
861 	 * thread_id=5729457&forum_id=5398
862 	 */
863 	struct usb_device_descriptor *desc;
864 	int port = -1;
865 	struct usb_device *parent = dev->parent;
866 	unsigned short portstatus;
867 
868 	/* send 64-byte GET-DEVICE-DESCRIPTOR request.  Since the descriptor is
869 	 * only 18 bytes long, this will terminate with a short packet.  But if
870 	 * the maxpacket size is 8 or 16 the device may be waiting to transmit
871 	 * some more, or keeps on retransmitting the 8 byte header. */
872 
873 	desc = (struct usb_device_descriptor *)tmpbuf;
874 	dev->descriptor.bMaxPacketSize0 = 64;	    /* Start off at 64 bytes  */
875 	/* Default to 64 byte max packet size */
876 	dev->maxpacketsize = PACKET_SIZE_64;
877 	dev->epmaxpacketin[0] = 64;
878 	dev->epmaxpacketout[0] = 64;
879 
880 	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, 64);
881 	if (err < 0) {
882 		debug("usb_new_device: usb_get_descriptor() failed\n");
883 		return 1;
884 	}
885 
886 	dev->descriptor.bMaxPacketSize0 = desc->bMaxPacketSize0;
887 	/*
888 	 * Fetch the device class, driver can use this info
889 	 * to differentiate between HUB and DEVICE.
890 	 */
891 	dev->descriptor.bDeviceClass = desc->bDeviceClass;
892 
893 	/* find the port number we're at */
894 	if (parent) {
895 		int j;
896 
897 		for (j = 0; j < parent->maxchild; j++) {
898 			if (parent->children[j] == dev) {
899 				port = j;
900 				break;
901 			}
902 		}
903 		if (port < 0) {
904 			printf("usb_new_device:cannot locate device's port.\n");
905 			return 1;
906 		}
907 
908 		/* reset the port for the second time */
909 		err = hub_port_reset(dev->parent, port, &portstatus);
910 		if (err < 0) {
911 			printf("\n     Couldn't reset port %i\n", port);
912 			return 1;
913 		}
914 	}
915 #endif
916 
917 	dev->epmaxpacketin[0] = dev->descriptor.bMaxPacketSize0;
918 	dev->epmaxpacketout[0] = dev->descriptor.bMaxPacketSize0;
919 	switch (dev->descriptor.bMaxPacketSize0) {
920 	case 8:
921 		dev->maxpacketsize  = PACKET_SIZE_8;
922 		break;
923 	case 16:
924 		dev->maxpacketsize = PACKET_SIZE_16;
925 		break;
926 	case 32:
927 		dev->maxpacketsize = PACKET_SIZE_32;
928 		break;
929 	case 64:
930 		dev->maxpacketsize = PACKET_SIZE_64;
931 		break;
932 	}
933 	dev->devnum = addr;
934 
935 	err = usb_set_address(dev); /* set address */
936 
937 	if (err < 0) {
938 		printf("\n      USB device not accepting new address " \
939 			"(error=%lX)\n", dev->status);
940 		return 1;
941 	}
942 
943 	mdelay(10);	/* Let the SET_ADDRESS settle */
944 
945 	tmp = sizeof(dev->descriptor);
946 
947 	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0,
948 				 tmpbuf, sizeof(dev->descriptor));
949 	if (err < tmp) {
950 		if (err < 0)
951 			printf("unable to get device descriptor (error=%d)\n",
952 			       err);
953 		else
954 			printf("USB device descriptor short read " \
955 				"(expected %i, got %i)\n", tmp, err);
956 		return 1;
957 	}
958 	memcpy(&dev->descriptor, tmpbuf, sizeof(dev->descriptor));
959 	/* correct le values */
960 	le16_to_cpus(&dev->descriptor.bcdUSB);
961 	le16_to_cpus(&dev->descriptor.idVendor);
962 	le16_to_cpus(&dev->descriptor.idProduct);
963 	le16_to_cpus(&dev->descriptor.bcdDevice);
964 	/* only support for one config for now */
965 	err = usb_get_configuration_no(dev, tmpbuf, 0);
966 	if (err < 0) {
967 		printf("usb_new_device: Cannot read configuration, " \
968 		       "skipping device %04x:%04x\n",
969 		       dev->descriptor.idVendor, dev->descriptor.idProduct);
970 		return -1;
971 	}
972 	usb_parse_config(dev, tmpbuf, 0);
973 	usb_set_maxpacket(dev);
974 	/* we set the default configuration here */
975 	if (usb_set_configuration(dev, dev->config.desc.bConfigurationValue)) {
976 		printf("failed to set default configuration " \
977 			"len %d, status %lX\n", dev->act_len, dev->status);
978 		return -1;
979 	}
980 	debug("new device strings: Mfr=%d, Product=%d, SerialNumber=%d\n",
981 	      dev->descriptor.iManufacturer, dev->descriptor.iProduct,
982 	      dev->descriptor.iSerialNumber);
983 	memset(dev->mf, 0, sizeof(dev->mf));
984 	memset(dev->prod, 0, sizeof(dev->prod));
985 	memset(dev->serial, 0, sizeof(dev->serial));
986 	if (dev->descriptor.iManufacturer)
987 		usb_string(dev, dev->descriptor.iManufacturer,
988 			   dev->mf, sizeof(dev->mf));
989 	if (dev->descriptor.iProduct)
990 		usb_string(dev, dev->descriptor.iProduct,
991 			   dev->prod, sizeof(dev->prod));
992 	if (dev->descriptor.iSerialNumber)
993 		usb_string(dev, dev->descriptor.iSerialNumber,
994 			   dev->serial, sizeof(dev->serial));
995 	debug("Manufacturer %s\n", dev->mf);
996 	debug("Product      %s\n", dev->prod);
997 	debug("SerialNumber %s\n", dev->serial);
998 	/* now prode if the device is a hub */
999 	usb_hub_probe(dev, 0);
1000 	return 0;
1001 }
1002 
1003 /* EOF */
1004