/*
   * Most of this source has been derived from the Linux USB
   * project:
   * (C) Copyright Linus Torvalds 1999
   * (C) Copyright Johannes Erdfelt 1999-2001
   * (C) Copyright Andreas Gal 1999
   * (C) Copyright Gregory P. Smith 1999
   * (C) Copyright Deti Fliegl 1999 (new USB architecture)
   * (C) Copyright Randy Dunlap 2000
   * (C) Copyright David Brownell 2000 (kernel hotplug, usb_device_id)
   * (C) Copyright Yggdrasil Computing, Inc. 2000
   *     (usb_device_id matching changes by Adam J. Richter)
   *
   * Adapted for U-Boot:
   * (C) Copyright 2001 Denis Peter, MPL AG Switzerland
   *
   * SPDX-License-Identifier:	GPL-2.0+
   */
  
  /*
   * How it works:
   *
   * Since this is a bootloader, the devices will not be automatic
   * (re)configured on hotplug, but after a restart of the USB the
   * device should work.
   *
   * For each transfer (except "Interrupt") we wait for completion.
   */
  #include <common.h>
  #include <command.h>
  #include <asm/processor.h>
  #include <linux/compiler.h>
  #include <linux/ctype.h>
  #include <asm/byteorder.h>
  #include <asm/unaligned.h>
  #include <errno.h>
  #include <usb.h>
  #ifdef CONFIG_4xx
  #include <asm/4xx_pci.h>
  #endif
  
  #define USB_BUFSIZ	512
  
  static struct usb_device usb_dev[USB_MAX_DEVICE];
  static int dev_index;
  static int asynch_allowed;
  
  char usb_started; /* flag for the started/stopped USB status */
  
  #ifndef CONFIG_USB_MAX_CONTROLLER_COUNT
  #define CONFIG_USB_MAX_CONTROLLER_COUNT 1
  #endif
  
  /***************************************************************************
   * Init USB Device
   */
  int usb_init(void)
  {
  	void *ctrl;
  	struct usb_device *dev;
  	int i, start_index = 0;
  	int controllers_initialized = 0;
  	int ret;
  
  	dev_index = 0;
  	asynch_allowed = 1;
  	usb_hub_reset();
  
  	/* first make all devices unknown */
  	for (i = 0; i < USB_MAX_DEVICE; i++) {
  		memset(&usb_dev[i], 0, sizeof(struct usb_device));
  		usb_dev[i].devnum = -1;
  	}
  
  	/* init low_level USB */
  	for (i = 0; i < CONFIG_USB_MAX_CONTROLLER_COUNT; i++) {
  		/* init low_level USB */
  		printf("USB%d:   ", i);
  		ret = usb_lowlevel_init(i, USB_INIT_HOST, &ctrl);
  		if (ret == -ENODEV) {	/* No such device. */
  			puts("Port not available.
  ");
  			controllers_initialized++;
  			continue;
  		}
  
  		if (ret) {		/* Other error. */
  			puts("lowlevel init failed
  ");
  			continue;
  		}
  		/*
  		 * lowlevel init is OK, now scan the bus for devices
  		 * i.e. search HUBs and configure them
  		 */
  		controllers_initialized++;
  		start_index = dev_index;
  		printf("scanning bus %d for devices... ", i);
  		dev = usb_alloc_new_device(ctrl);
  		/*
  		 * device 0 is always present
  		 * (root hub, so let it analyze)
  		 */
  		if (dev)
  			usb_new_device(dev);
  
  		if (start_index == dev_index)
  			puts("No USB Device found
  ");
  		else
  			printf("%d USB Device(s) found
  ",
  				dev_index - start_index);
  
  		usb_started = 1;
  	}
  
  	debug("scan end
  ");
  	/* if we were not able to find at least one working bus, bail out */
  	if (controllers_initialized == 0)
  		puts("USB error: all controllers failed lowlevel init
  ");
  
  	return usb_started ? 0 : -1;
  }
  
  /******************************************************************************
   * Stop USB this stops the LowLevel Part and deregisters USB devices.
   */
  int usb_stop(void)
  {
  	int i;
  
  	if (usb_started) {
  		asynch_allowed = 1;
  		usb_started = 0;
  		usb_hub_reset();
  
  		for (i = 0; i < CONFIG_USB_MAX_CONTROLLER_COUNT; i++) {
  			if (usb_lowlevel_stop(i))
  				printf("failed to stop USB controller %d
  ", i);
  		}
  	}
  
  	return 0;
  }
  
  /*
   * disables the asynch behaviour of the control message. This is used for data
   * transfers that uses the exclusiv access to the control and bulk messages.
   * Returns the old value so it can be restored later.
   */
  int usb_disable_asynch(int disable)
  {
  	int old_value = asynch_allowed;
  
  	asynch_allowed = !disable;
  	return old_value;
  }
  
  
  /*-------------------------------------------------------------------
   * Message wrappers.
   *
   */
  
  /*
   * submits an Interrupt Message
   */
  int usb_submit_int_msg(struct usb_device *dev, unsigned long pipe,
  			void *buffer, int transfer_len, int interval)
  {
  	return submit_int_msg(dev, pipe, buffer, transfer_len, interval);
  }
  
  /*
   * submits a control message and waits for comletion (at least timeout * 1ms)
   * If timeout is 0, we don't wait for completion (used as example to set and
   * clear keyboards LEDs). For data transfers, (storage transfers) we don't
   * allow control messages with 0 timeout, by previousely resetting the flag
   * asynch_allowed (usb_disable_asynch(1)).
   * returns the transfered length if OK or -1 if error. The transfered length
   * and the current status are stored in the dev->act_len and dev->status.
   */
  int usb_control_msg(struct usb_device *dev, unsigned int pipe,
  			unsigned char request, unsigned char requesttype,
  			unsigned short value, unsigned short index,
  			void *data, unsigned short size, int timeout)
  {
  	ALLOC_CACHE_ALIGN_BUFFER(struct devrequest, setup_packet, 1);
  
  	if ((timeout == 0) && (!asynch_allowed)) {
  		/* request for a asynch control pipe is not allowed */
  		return -1;
  	}
  
  	/* set setup command */
  	setup_packet->requesttype = requesttype;
  	setup_packet->request = request;
  	setup_packet->value = cpu_to_le16(value);
  	setup_packet->index = cpu_to_le16(index);
  	setup_packet->length = cpu_to_le16(size);
  	debug("usb_control_msg: request: 0x%X, requesttype: 0x%X, " \
  	      "value 0x%X index 0x%X length 0x%X
  ",
  	      request, requesttype, value, index, size);
  	dev->status = USB_ST_NOT_PROC; /*not yet processed */
  
  	if (submit_control_msg(dev, pipe, data, size, setup_packet) < 0)
  		return -1;
  	if (timeout == 0)
  		return (int)size;
  
  	/*
  	 * Wait for status to update until timeout expires, USB driver
  	 * interrupt handler may set the status when the USB operation has
  	 * been completed.
  	 */
  	while (timeout--) {
  		if (!((volatile unsigned long)dev->status & USB_ST_NOT_PROC))
  			break;
  		mdelay(1);
  	}
  	if (dev->status)
  		return -1;
  
  	return dev->act_len;
  
  }
  
  /*-------------------------------------------------------------------
   * submits bulk message, and waits for completion. returns 0 if Ok or
   * -1 if Error.
   * synchronous behavior
   */
  int usb_bulk_msg(struct usb_device *dev, unsigned int pipe,
  			void *data, int len, int *actual_length, int timeout)
  {
  	if (len < 0)
  		return -1;
  	dev->status = USB_ST_NOT_PROC; /*not yet processed */
  	if (submit_bulk_msg(dev, pipe, data, len) < 0)
  		return -1;
  	while (timeout--) {
  		if (!((volatile unsigned long)dev->status & USB_ST_NOT_PROC))
  			break;
  		mdelay(1);
  	}
  	*actual_length = dev->act_len;
  	if (dev->status == 0)
  		return 0;
  	else
  		return -1;
  }
  
  
  /*-------------------------------------------------------------------
   * Max Packet stuff
   */
  
  /*
   * returns the max packet size, depending on the pipe direction and
   * the configurations values
   */
  int usb_maxpacket(struct usb_device *dev, unsigned long pipe)
  {
  	/* direction is out -> use emaxpacket out */
  	if ((pipe & USB_DIR_IN) == 0)
  		return dev->epmaxpacketout[((pipe>>15) & 0xf)];
  	else
  		return dev->epmaxpacketin[((pipe>>15) & 0xf)];
  }
  
  /*
   * The routine usb_set_maxpacket_ep() is extracted from the loop of routine
   * usb_set_maxpacket(), because the optimizer of GCC 4.x chokes on this routine
   * when it is inlined in 1 single routine. What happens is that the register r3
   * is used as loop-count 'i', but gets overwritten later on.
   * This is clearly a compiler bug, but it is easier to workaround it here than
   * to update the compiler (Occurs with at least several GCC 4.{1,2},x
   * CodeSourcery compilers like e.g. 2007q3, 2008q1, 2008q3 lite editions on ARM)
   *
   * NOTE: Similar behaviour was observed with GCC4.6 on ARMv5.
   */
  static void noinline
  usb_set_maxpacket_ep(struct usb_device *dev, int if_idx, int ep_idx)
  {
  	int b;
  	struct usb_endpoint_descriptor *ep;
  	u16 ep_wMaxPacketSize;
  
  	ep = &dev->config.if_desc[if_idx].ep_desc[ep_idx];
  
  	b = ep->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK;
  	ep_wMaxPacketSize = get_unaligned(&ep->wMaxPacketSize);
  
  	if ((ep->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
  						USB_ENDPOINT_XFER_CONTROL) {
  		/* Control => bidirectional */
  		dev->epmaxpacketout[b] = ep_wMaxPacketSize;
  		dev->epmaxpacketin[b] = ep_wMaxPacketSize;
  		debug("##Control EP epmaxpacketout/in[%d] = %d
  ",
  		      b, dev->epmaxpacketin[b]);
  	} else {
  		if ((ep->bEndpointAddress & 0x80) == 0) {
  			/* OUT Endpoint */
  			if (ep_wMaxPacketSize > dev->epmaxpacketout[b]) {
  				dev->epmaxpacketout[b] = ep_wMaxPacketSize;
  				debug("##EP epmaxpacketout[%d] = %d
  ",
  				      b, dev->epmaxpacketout[b]);
  			}
  		} else {
  			/* IN Endpoint */
  			if (ep_wMaxPacketSize > dev->epmaxpacketin[b]) {
  				dev->epmaxpacketin[b] = ep_wMaxPacketSize;
  				debug("##EP epmaxpacketin[%d] = %d
  ",
  				      b, dev->epmaxpacketin[b]);
  			}
  		} /* if out */
  	} /* if control */
  }
  
  /*
   * set the max packed value of all endpoints in the given configuration
   */
  static int usb_set_maxpacket(struct usb_device *dev)
  {
  	int i, ii;
  
  	for (i = 0; i < dev->config.desc.bNumInterfaces; i++)
  		for (ii = 0; ii < dev->config.if_desc[i].desc.bNumEndpoints; ii++)
  			usb_set_maxpacket_ep(dev, i, ii);
  
  	return 0;
  }
  
  /*******************************************************************************
   * Parse the config, located in buffer, and fills the dev->config structure.
   * Note that all little/big endian swapping are done automatically.
   * (wTotalLength has already been swapped and sanitized when it was read.)
   */
  static int usb_parse_config(struct usb_device *dev,
  			unsigned char *buffer, int cfgno)
  {
  	struct usb_descriptor_header *head;
  	int index, ifno, epno, curr_if_num;
  	u16 ep_wMaxPacketSize;
  	struct usb_interface *if_desc = NULL;
  
  	ifno = -1;
  	epno = -1;
  	curr_if_num = -1;
  
  	dev->configno = cfgno;
  	head = (struct usb_descriptor_header *) &buffer[0];
  	if (head->bDescriptorType != USB_DT_CONFIG) {
  		printf(" ERROR: NOT USB_CONFIG_DESC %x
  ",
  			head->bDescriptorType);
  		return -1;
  	}
  	if (head->bLength != USB_DT_CONFIG_SIZE) {
  		printf("ERROR: Invalid USB CFG length (%d)
  ", head->bLength);
  		return -1;
  	}
  	memcpy(&dev->config, head, USB_DT_CONFIG_SIZE);
  	dev->config.no_of_if = 0;
  
  	index = dev->config.desc.bLength;
  	/* Ok the first entry must be a configuration entry,
  	 * now process the others */
  	head = (struct usb_descriptor_header *) &buffer[index];
  	while (index + 1 < dev->config.desc.wTotalLength && head->bLength) {
  		switch (head->bDescriptorType) {
  		case USB_DT_INTERFACE:
  			if (head->bLength != USB_DT_INTERFACE_SIZE) {
  				printf("ERROR: Invalid USB IF length (%d)
  ",
  					head->bLength);
  				break;
  			}
  			if (index + USB_DT_INTERFACE_SIZE >
  			    dev->config.desc.wTotalLength) {
  				puts("USB IF descriptor overflowed buffer!
  ");
  				break;
  			}
  			if (((struct usb_interface_descriptor *) \
  			     head)->bInterfaceNumber != curr_if_num) {
  				/* this is a new interface, copy new desc */
  				ifno = dev->config.no_of_if;
  				if (ifno >= USB_MAXINTERFACES) {
  					puts("Too many USB interfaces!
  ");
  					/* try to go on with what we have */
  					return 1;
  				}
  				if_desc = &dev->config.if_desc[ifno];
  				dev->config.no_of_if++;
  				memcpy(if_desc, head,
  					USB_DT_INTERFACE_SIZE);
  				if_desc->no_of_ep = 0;
  				if_desc->num_altsetting = 1;
  				curr_if_num =
  				     if_desc->desc.bInterfaceNumber;
  			} else {
  				/* found alternate setting for the interface */
  				if (ifno >= 0) {
  					if_desc = &dev->config.if_desc[ifno];
  					if_desc->num_altsetting++;
  				}
  			}
  			break;
  		case USB_DT_ENDPOINT:
  			if (head->bLength != USB_DT_ENDPOINT_SIZE) {
  				printf("ERROR: Invalid USB EP length (%d)
  ",
  					head->bLength);
  				break;
  			}
  			if (index + USB_DT_ENDPOINT_SIZE >
  			    dev->config.desc.wTotalLength) {
  				puts("USB EP descriptor overflowed buffer!
  ");
  				break;
  			}
  			if (ifno < 0) {
  				puts("Endpoint descriptor out of order!
  ");
  				break;
  			}
  			epno = dev->config.if_desc[ifno].no_of_ep;
  			if_desc = &dev->config.if_desc[ifno];
  			if (epno > USB_MAXENDPOINTS) {
  				printf("Interface %d has too many endpoints!
  ",
  					if_desc->desc.bInterfaceNumber);
  				return 1;
  			}
  			/* found an endpoint */
  			if_desc->no_of_ep++;
  			memcpy(&if_desc->ep_desc[epno], head,
  				USB_DT_ENDPOINT_SIZE);
  			ep_wMaxPacketSize = get_unaligned(&dev->config.\
  							if_desc[ifno].\
  							ep_desc[epno].\
  							wMaxPacketSize);
  			put_unaligned(le16_to_cpu(ep_wMaxPacketSize),
  					&dev->config.\
  					if_desc[ifno].\
  					ep_desc[epno].\
  					wMaxPacketSize);
  			debug("if %d, ep %d
  ", ifno, epno);
  			break;
  		case USB_DT_SS_ENDPOINT_COMP:
  			if (head->bLength != USB_DT_SS_EP_COMP_SIZE) {
  				printf("ERROR: Invalid USB EPC length (%d)
  ",
  					head->bLength);
  				break;
  			}
  			if (index + USB_DT_SS_EP_COMP_SIZE >
  			    dev->config.desc.wTotalLength) {
  				puts("USB EPC descriptor overflowed buffer!
  ");
  				break;
  			}
  			if (ifno < 0 || epno < 0) {
  				puts("EPC descriptor out of order!
  ");
  				break;
  			}
  			if_desc = &dev->config.if_desc[ifno];
  			memcpy(&if_desc->ss_ep_comp_desc[epno], head,
  				USB_DT_SS_EP_COMP_SIZE);
  			break;
  		default:
  			if (head->bLength == 0)
  				return 1;
  
  			debug("unknown Description Type : %x
  ",
  			      head->bDescriptorType);
  
  #ifdef DEBUG
  			{
  				unsigned char *ch = (unsigned char *)head;
  				int i;
  
  				for (i = 0; i < head->bLength; i++)
  					debug("%02X ", *ch++);
  				debug("
  
  
  ");
  			}
  #endif
  			break;
  		}
  		index += head->bLength;
  		head = (struct usb_descriptor_header *)&buffer[index];
  	}
  	return 1;
  }
  
  /***********************************************************************
   * Clears an endpoint
   * endp: endpoint number in bits 0-3;
   * direction flag in bit 7 (1 = IN, 0 = OUT)
   */
  int usb_clear_halt(struct usb_device *dev, int pipe)
  {
  	int result;
  	int endp = usb_pipeendpoint(pipe)|(usb_pipein(pipe)<<7);
  
  	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
  				 USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT, 0,
  				 endp, NULL, 0, USB_CNTL_TIMEOUT * 3);
  
  	/* don't clear if failed */
  	if (result < 0)
  		return result;
  
  	/*
  	 * NOTE: we do not get status and verify reset was successful
  	 * as some devices are reported to lock up upon this check..
  	 */
  
  	usb_endpoint_running(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe));
  
  	/* toggle is reset on clear */
  	usb_settoggle(dev, usb_pipeendpoint(pipe), usb_pipeout(pipe), 0);
  	return 0;
  }
  
  
  /**********************************************************************
   * get_descriptor type
   */
  static int usb_get_descriptor(struct usb_device *dev, unsigned char type,
  			unsigned char index, void *buf, int size)
  {
  	int res;
  	res = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
  			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
  			(type << 8) + index, 0,
  			buf, size, USB_CNTL_TIMEOUT);
  	return res;
  }
  
  /**********************************************************************
   * gets configuration cfgno and store it in the buffer
   */
  int usb_get_configuration_no(struct usb_device *dev,
  			     unsigned char *buffer, int cfgno)
  {
  	int result;
  	unsigned int length;
  	struct usb_config_descriptor *config;
  
  	config = (struct usb_config_descriptor *)&buffer[0];
  	result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno, buffer, 9);
  	if (result < 9) {
  		if (result < 0)
  			printf("unable to get descriptor, error %lX
  ",
  				dev->status);
  		else
  			printf("config descriptor too short " \
  				"(expected %i, got %i)
  ", 9, result);
  		return -1;
  	}
  	length = le16_to_cpu(config->wTotalLength);
  
  	if (length > USB_BUFSIZ) {
  		printf("%s: failed to get descriptor - too long: %d
  ",
  			__func__, length);
  		return -1;
  	}
  
  	result = usb_get_descriptor(dev, USB_DT_CONFIG, cfgno, buffer, length);
  	debug("get_conf_no %d Result %d, wLength %d
  ", cfgno, result, length);
  	config->wTotalLength = length; /* validated, with CPU byte order */
  
  	return result;
  }
  
  /********************************************************************
   * set address of a device to the value in dev->devnum.
   * This can only be done by addressing the device via the default address (0)
   */
  static int usb_set_address(struct usb_device *dev)
  {
  	int res;
  
  	debug("set address %d
  ", dev->devnum);
  	res = usb_control_msg(dev, usb_snddefctrl(dev),
  				USB_REQ_SET_ADDRESS, 0,
  				(dev->devnum), 0,
  				NULL, 0, USB_CNTL_TIMEOUT);
  	return res;
  }
  
  /********************************************************************
   * set interface number to interface
   */
  int usb_set_interface(struct usb_device *dev, int interface, int alternate)
  {
  	struct usb_interface *if_face = NULL;
  	int ret, i;
  
  	for (i = 0; i < dev->config.desc.bNumInterfaces; i++) {
  		if (dev->config.if_desc[i].desc.bInterfaceNumber == interface) {
  			if_face = &dev->config.if_desc[i];
  			break;
  		}
  	}
  	if (!if_face) {
  		printf("selecting invalid interface %d", interface);
  		return -1;
  	}
  	/*
  	 * We should return now for devices with only one alternate setting.
  	 * According to 9.4.10 of the Universal Serial Bus Specification
  	 * Revision 2.0 such devices can return with a STALL. This results in
  	 * some USB sticks timeouting during initialization and then being
  	 * unusable in U-Boot.
  	 */
  	if (if_face->num_altsetting == 1)
  		return 0;
  
  	ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
  				USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE,
  				alternate, interface, NULL, 0,
  				USB_CNTL_TIMEOUT * 5);
  	if (ret < 0)
  		return ret;
  
  	return 0;
  }
  
  /********************************************************************
   * set configuration number to configuration
   */
  static int usb_set_configuration(struct usb_device *dev, int configuration)
  {
  	int res;
  	debug("set configuration %d
  ", configuration);
  	/* set setup command */
  	res = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
  				USB_REQ_SET_CONFIGURATION, 0,
  				configuration, 0,
  				NULL, 0, USB_CNTL_TIMEOUT);
  	if (res == 0) {
  		dev->toggle[0] = 0;
  		dev->toggle[1] = 0;
  		return 0;
  	} else
  		return -1;
  }
  
  /********************************************************************
   * set protocol to protocol
   */
  int usb_set_protocol(struct usb_device *dev, int ifnum, int protocol)
  {
  	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
  		USB_REQ_SET_PROTOCOL, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
  		protocol, ifnum, NULL, 0, USB_CNTL_TIMEOUT);
  }
  
  /********************************************************************
   * set idle
   */
  int usb_set_idle(struct usb_device *dev, int ifnum, int duration, int report_id)
  {
  	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
  		USB_REQ_SET_IDLE, USB_TYPE_CLASS | USB_RECIP_INTERFACE,
  		(duration << 8) | report_id, ifnum, NULL, 0, USB_CNTL_TIMEOUT);
  }
  
  /********************************************************************
   * get report
   */
  int usb_get_report(struct usb_device *dev, int ifnum, unsigned char type,
  		   unsigned char id, void *buf, int size)
  {
  	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
  			USB_REQ_GET_REPORT,
  			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_INTERFACE,
  			(type << 8) + id, ifnum, buf, size, USB_CNTL_TIMEOUT);
  }
  
  /********************************************************************
   * get class descriptor
   */
  int usb_get_class_descriptor(struct usb_device *dev, int ifnum,
  		unsigned char type, unsigned char id, void *buf, int size)
  {
  	return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
  		USB_REQ_GET_DESCRIPTOR, USB_RECIP_INTERFACE | USB_DIR_IN,
  		(type << 8) + id, ifnum, buf, size, USB_CNTL_TIMEOUT);
  }
  
  /********************************************************************
   * get string index in buffer
   */
  static int usb_get_string(struct usb_device *dev, unsigned short langid,
  		   unsigned char index, void *buf, int size)
  {
  	int i;
  	int result;
  
  	for (i = 0; i < 3; ++i) {
  		/* some devices are flaky */
  		result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
  			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
  			(USB_DT_STRING << 8) + index, langid, buf, size,
  			USB_CNTL_TIMEOUT);
  
  		if (result > 0)
  			break;
  	}
  
  	return result;
  }
  
  
  static void usb_try_string_workarounds(unsigned char *buf, int *length)
  {
  	int newlength, oldlength = *length;
  
  	for (newlength = 2; newlength + 1 < oldlength; newlength += 2)
  		if (!isprint(buf[newlength]) || buf[newlength + 1])
  			break;
  
  	if (newlength > 2) {
  		buf[0] = newlength;
  		*length = newlength;
  	}
  }
  
  
  static int usb_string_sub(struct usb_device *dev, unsigned int langid,
  		unsigned int index, unsigned char *buf)
  {
  	int rc;
  
  	/* Try to read the string descriptor by asking for the maximum
  	 * possible number of bytes */
  	rc = usb_get_string(dev, langid, index, buf, 255);
  
  	/* If that failed try to read the descriptor length, then
  	 * ask for just that many bytes */
  	if (rc < 2) {
  		rc = usb_get_string(dev, langid, index, buf, 2);
  		if (rc == 2)
  			rc = usb_get_string(dev, langid, index, buf, buf[0]);
  	}
  
  	if (rc >= 2) {
  		if (!buf[0] && !buf[1])
  			usb_try_string_workarounds(buf, &rc);
  
  		/* There might be extra junk at the end of the descriptor */
  		if (buf[0] < rc)
  			rc = buf[0];
  
  		rc = rc - (rc & 1); /* force a multiple of two */
  	}
  
  	if (rc < 2)
  		rc = -1;
  
  	return rc;
  }
  
  
  /********************************************************************
   * usb_string:
   * Get string index and translate it to ascii.
   * returns string length (> 0) or error (< 0)
   */
  int usb_string(struct usb_device *dev, int index, char *buf, size_t size)
  {
  	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, mybuf, USB_BUFSIZ);
  	unsigned char *tbuf;
  	int err;
  	unsigned int u, idx;
  
  	if (size <= 0 || !buf || !index)
  		return -1;
  	buf[0] = 0;
  	tbuf = &mybuf[0];
  
  	/* get langid for strings if it's not yet known */
  	if (!dev->have_langid) {
  		err = usb_string_sub(dev, 0, 0, tbuf);
  		if (err < 0) {
  			debug("error getting string descriptor 0 " \
  			      "(error=%lx)
  ", dev->status);
  			return -1;
  		} else if (tbuf[0] < 4) {
  			debug("string descriptor 0 too short
  ");
  			return -1;
  		} else {
  			dev->have_langid = -1;
  			dev->string_langid = tbuf[2] | (tbuf[3] << 8);
  				/* always use the first langid listed */
  			debug("USB device number %d default " \
  			      "language ID 0x%x
  ",
  			      dev->devnum, dev->string_langid);
  		}
  	}
  
  	err = usb_string_sub(dev, dev->string_langid, index, tbuf);
  	if (err < 0)
  		return err;
  
  	size--;		/* leave room for trailing NULL char in output buffer */
  	for (idx = 0, u = 2; u < err; u += 2) {
  		if (idx >= size)
  			break;
  		if (tbuf[u+1])			/* high byte */
  			buf[idx++] = '?';  /* non-ASCII character */
  		else
  			buf[idx++] = tbuf[u];
  	}
  	buf[idx] = 0;
  	err = idx;
  	return err;
  }
  
  
  /********************************************************************
   * USB device handling:
   * the USB device are static allocated [USB_MAX_DEVICE].
   */
  
  
  /* returns a pointer to the device with the index [index].
   * if the device is not assigned (dev->devnum==-1) returns NULL
   */
  struct usb_device *usb_get_dev_index(int index)
  {
  	if (usb_dev[index].devnum == -1)
  		return NULL;
  	else
  		return &usb_dev[index];
  }
  
  /* returns a pointer of a new device structure or NULL, if
   * no device struct is available
   */
  struct usb_device *usb_alloc_new_device(void *controller)
  {
  	int i;
  	debug("New Device %d
  ", dev_index);
  	if (dev_index == USB_MAX_DEVICE) {
  		printf("ERROR, too many USB Devices, max=%d
  ", USB_MAX_DEVICE);
  		return NULL;
  	}
  	/* default Address is 0, real addresses start with 1 */
  	usb_dev[dev_index].devnum = dev_index + 1;
  	usb_dev[dev_index].maxchild = 0;
  	for (i = 0; i < USB_MAXCHILDREN; i++)
  		usb_dev[dev_index].children[i] = NULL;
  	usb_dev[dev_index].parent = NULL;
  	usb_dev[dev_index].controller = controller;
  	dev_index++;
  	return &usb_dev[dev_index - 1];
  }
  
  /*
   * Free the newly created device node.
   * Called in error cases where configuring a newly attached
   * device fails for some reason.
   */
  void usb_free_device(void)
  {
  	dev_index--;
  	debug("Freeing device node: %d
  ", dev_index);
  	memset(&usb_dev[dev_index], 0, sizeof(struct usb_device));
  	usb_dev[dev_index].devnum = -1;
  }
  
  /*
   * XHCI issues Enable Slot command and thereafter
   * allocates device contexts. Provide a weak alias
   * function for the purpose, so that XHCI overrides it
   * and EHCI/OHCI just work out of the box.
   */
  __weak int usb_alloc_device(struct usb_device *udev)
  {
  	return 0;
  }
  /*
   * By the time we get here, the device has gotten a new device ID
   * and is in the default state. We need to identify the thing and
   * get the ball rolling..
   *
   * Returns 0 for success, != 0 for error.
   */
  int usb_new_device(struct usb_device *dev)
  {
  	int addr, err;
  	int tmp;
  	ALLOC_CACHE_ALIGN_BUFFER(unsigned char, tmpbuf, USB_BUFSIZ);
  
  	/*
  	 * Allocate usb 3.0 device context.
  	 * USB 3.0 (xHCI) protocol tries to allocate device slot
  	 * and related data structures first. This call does that.
  	 * Refer to sec 4.3.2 in xHCI spec rev1.0
  	 */
  	if (usb_alloc_device(dev)) {
  		printf("Cannot allocate device context to get SLOT_ID
  ");
  		return -1;
  	}
  
  	/* We still haven't set the Address yet */
  	addr = dev->devnum;
  	dev->devnum = 0;
  
  #ifdef CONFIG_LEGACY_USB_INIT_SEQ
  	/* this is the old and known way of initializing devices, it is
  	 * different than what Windows and Linux are doing. Windows and Linux
  	 * both retrieve 64 bytes while reading the device descriptor
  	 * Several USB stick devices report ERR: CTL_TIMEOUT, caused by an
  	 * invalid header while reading 8 bytes as device descriptor. */
  	dev->descriptor.bMaxPacketSize0 = 8;	    /* Start off at 8 bytes  */
  	dev->maxpacketsize = PACKET_SIZE_8;
  	dev->epmaxpacketin[0] = 8;
  	dev->epmaxpacketout[0] = 8;
  
  	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0, tmpbuf, 8);
  	if (err < 8) {
  		printf("
        USB device not responding, " \
  		       "giving up (status=%lX)
  ", dev->status);
  		return 1;
  	}
  	memcpy(&dev->descriptor, tmpbuf, 8);
  #else
  	/* This is a Windows scheme of initialization sequence, with double
  	 * reset of the device (Linux uses the same sequence)
  	 * Some equipment is said to work only with such init sequence; this
  	 * patch is based on the work by Alan Stern:
  	 * http://sourceforge.net/mailarchive/forum.php?
  	 * thread_id=5729457&forum_id=5398
  	 */
  	__maybe_unused struct usb_device_descriptor *desc;
  	struct usb_device *parent = dev->parent;
  	unsigned short portstatus;
  
  	/* send 64-byte GET-DEVICE-DESCRIPTOR request.  Since the descriptor is
  	 * only 18 bytes long, this will terminate with a short packet.  But if
  	 * the maxpacket size is 8 or 16 the device may be waiting to transmit
  	 * some more, or keeps on retransmitting the 8 byte header. */
  
  	desc = (struct usb_device_descriptor *)tmpbuf;
  	dev->descriptor.bMaxPacketSize0 = 64;	    /* Start off at 64 bytes  */
  	/* Default to 64 byte max packet size */
  	dev->maxpacketsize = PACKET_SIZE_64;
  	dev->epmaxpacketin[0] = 64;
  	dev->epmaxpacketout[0] = 64;
  
  	/*
  	 * XHCI needs to issue a Address device command to setup
  	 * proper device context structures, before it can interact
  	 * with the device. So a get_descriptor will fail before any
  	 * of that is done for XHCI unlike EHCI.
  	 */
  #ifndef CONFIG_USB_XHCI
  	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, 64);
  	if (err < 0) {
  		debug("usb_new_device: usb_get_descriptor() failed
  ");
  		return 1;
  	}
  
  	dev->descriptor.bMaxPacketSize0 = desc->bMaxPacketSize0;
  	/*
  	 * Fetch the device class, driver can use this info
  	 * to differentiate between HUB and DEVICE.
  	 */
  	dev->descriptor.bDeviceClass = desc->bDeviceClass;
  #endif
  
  	if (parent) {
  		/* reset the port for the second time */
  		err = hub_port_reset(dev->parent, dev->portnr - 1, &portstatus);
  		if (err < 0) {
  			printf("
       Couldn't reset port %i
  ", dev->portnr);
  			return 1;
  		}
  	} else {
  		usb_reset_root_port();
  	}
  #endif
  
  	dev->epmaxpacketin[0] = dev->descriptor.bMaxPacketSize0;
  	dev->epmaxpacketout[0] = dev->descriptor.bMaxPacketSize0;
  	switch (dev->descriptor.bMaxPacketSize0) {
  	case 8:
  		dev->maxpacketsize  = PACKET_SIZE_8;
  		break;
  	case 16:
  		dev->maxpacketsize = PACKET_SIZE_16;
  		break;
  	case 32:
  		dev->maxpacketsize = PACKET_SIZE_32;
  		break;
  	case 64:
  		dev->maxpacketsize = PACKET_SIZE_64;
  		break;
  	}
  	dev->devnum = addr;
  
  	err = usb_set_address(dev); /* set address */
  
  	if (err < 0) {
  		printf("
        USB device not accepting new address " \
  			"(error=%lX)
  ", dev->status);
  		return 1;
  	}
  
  	mdelay(10);	/* Let the SET_ADDRESS settle */
  
  	tmp = sizeof(dev->descriptor);
  
  	err = usb_get_descriptor(dev, USB_DT_DEVICE, 0,
  				 tmpbuf, sizeof(dev->descriptor));
  	if (err < tmp) {
  		if (err < 0)
  			printf("unable to get device descriptor (error=%d)
  ",
  			       err);
  		else
  			printf("USB device descriptor short read " \
  				"(expected %i, got %i)
  ", tmp, err);
  		return 1;
  	}
  	memcpy(&dev->descriptor, tmpbuf, sizeof(dev->descriptor));
  	/* correct le values */
  	le16_to_cpus(&dev->descriptor.bcdUSB);
  	le16_to_cpus(&dev->descriptor.idVendor);
  	le16_to_cpus(&dev->descriptor.idProduct);
  	le16_to_cpus(&dev->descriptor.bcdDevice);
  	/* only support for one config for now */
  	err = usb_get_configuration_no(dev, tmpbuf, 0);
  	if (err < 0) {
  		printf("usb_new_device: Cannot read configuration, " \
  		       "skipping device %04x:%04x
  ",
  		       dev->descriptor.idVendor, dev->descriptor.idProduct);
  		return -1;
  	}
  	usb_parse_config(dev, tmpbuf, 0);
  	usb_set_maxpacket(dev);
  	/* we set the default configuration here */
  	if (usb_set_configuration(dev, dev->config.desc.bConfigurationValue)) {
  		printf("failed to set default configuration " \
  			"len %d, status %lX
  ", dev->act_len, dev->status);
  		return -1;
  	}
  	debug("new device strings: Mfr=%d, Product=%d, SerialNumber=%d
  ",
  	      dev->descriptor.iManufacturer, dev->descriptor.iProduct,
  	      dev->descriptor.iSerialNumber);
  	memset(dev->mf, 0, sizeof(dev->mf));
  	memset(dev->prod, 0, sizeof(dev->prod));
  	memset(dev->serial, 0, sizeof(dev->serial));
  	if (dev->descriptor.iManufacturer)
  		usb_string(dev, dev->descriptor.iManufacturer,
  			   dev->mf, sizeof(dev->mf));
  	if (dev->descriptor.iProduct)
  		usb_string(dev, dev->descriptor.iProduct,
  			   dev->prod, sizeof(dev->prod));
  	if (dev->descriptor.iSerialNumber)
  		usb_string(dev, dev->descriptor.iSerialNumber,
  			   dev->serial, sizeof(dev->serial));
  	debug("Manufacturer %s
  ", dev->mf);
  	debug("Product      %s
  ", dev->prod);
  	debug("SerialNumber %s
  ", dev->serial);
  	/* now prode if the device is a hub */
  	usb_hub_probe(dev, 0);
  	return 0;
  }
  
  __weak
  int board_usb_init(int index, enum usb_init_type init)
  {
  	return 0;
  }
  /* EOF */