Release 4.7 drivers/usb/core/message.c
  
  
/*
 * message.c - synchronous message handling
 */
#include <linux/pci.h>	/* for scatterlist macros */
#include <linux/usb.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/timer.h>
#include <linux/ctype.h>
#include <linux/nls.h>
#include <linux/device.h>
#include <linux/scatterlist.h>
#include <linux/usb/quirks.h>
#include <linux/usb/hcd.h>	/* for usbcore internals */
#include <asm/byteorder.h>
#include "usb.h"
static void cancel_async_set_config(struct usb_device *udev);
struct api_context {
	
struct completion	done;
	
int			status;
};
static void usb_api_blocking_completion(struct urb *urb)
{
	struct api_context *ctx = urb->context;
	ctx->status = urb->status;
	complete(&ctx->done);
}
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/*
 * Starts urb and waits for completion or timeout. Note that this call
 * is NOT interruptible. Many device driver i/o requests should be
 * interruptible and therefore these drivers should implement their
 * own interruptible routines.
 */
static int usb_start_wait_urb(struct urb *urb, int timeout, int *actual_length)
{
	struct api_context ctx;
	unsigned long expire;
	int retval;
	init_completion(&ctx.done);
	urb->context = &ctx;
	urb->actual_length = 0;
	retval = usb_submit_urb(urb, GFP_NOIO);
	if (unlikely(retval))
		goto out;
	expire = timeout ? msecs_to_jiffies(timeout) : MAX_SCHEDULE_TIMEOUT;
	if (!wait_for_completion_timeout(&ctx.done, expire)) {
		usb_kill_urb(urb);
		retval = (ctx.status == -ENOENT ? -ETIMEDOUT : ctx.status);
		dev_dbg(&urb->dev->dev,
			"%s timed out on ep%d%s len=%u/%u\n",
			current->comm,
			usb_endpoint_num(&urb->ep->desc),
			usb_urb_dir_in(urb) ? "in" : "out",
			urb->actual_length,
			urb->transfer_buffer_length);
	} else
		retval = ctx.status;
out:
	if (actual_length)
		*actual_length = urb->actual_length;
	usb_free_urb(urb);
	return retval;
}
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/*-------------------------------------------------------------------*/
/* returns status (negative) or length (positive) */
static int usb_internal_control_msg(struct usb_device *usb_dev,
				    unsigned int pipe,
				    struct usb_ctrlrequest *cmd,
				    void *data, int len, int timeout)
{
	struct urb *urb;
	int retv;
	int length;
	urb = usb_alloc_urb(0, GFP_NOIO);
	if (!urb)
		return -ENOMEM;
	usb_fill_control_urb(urb, usb_dev, pipe, (unsigned char *)cmd, data,
			     len, usb_api_blocking_completion, NULL);
	retv = usb_start_wait_urb(urb, timeout, &length);
	if (retv < 0)
		return retv;
	else
		return length;
}
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 | Total | 108 | 100.00% | 5 | 100.00% | 
/**
 * usb_control_msg - Builds a control urb, sends it off and waits for completion
 * @dev: pointer to the usb device to send the message to
 * @pipe: endpoint "pipe" to send the message to
 * @request: USB message request value
 * @requesttype: USB message request type value
 * @value: USB message value
 * @index: USB message index value
 * @data: pointer to the data to send
 * @size: length in bytes of the data to send
 * @timeout: time in msecs to wait for the message to complete before timing
 *      out (if 0 the wait is forever)
 *
 * Context: !in_interrupt ()
 *
 * This function sends a simple control message to a specified endpoint and
 * waits for the message to complete, or timeout.
 *
 * Don't use this function from within an interrupt context, like a bottom half
 * handler.  If you need an asynchronous message, or need to send a message
 * from within interrupt context, use usb_submit_urb().
 * If a thread in your driver uses this call, make sure your disconnect()
 * method can wait for it to complete.  Since you don't have a handle on the
 * URB used, you can't cancel the request.
 *
 * Return: If successful, the number of bytes transferred. Otherwise, a negative
 * error number.
 */
int usb_control_msg(struct usb_device *dev, unsigned int pipe, __u8 request,
		    __u8 requesttype, __u16 value, __u16 index, void *data,
		    __u16 size, int timeout)
{
	struct usb_ctrlrequest *dr;
	int ret;
	dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO);
	if (!dr)
		return -ENOMEM;
	dr->bRequestType = requesttype;
	dr->bRequest = request;
	dr->wValue = cpu_to_le16(value);
	dr->wIndex = cpu_to_le16(index);
	dr->wLength = cpu_to_le16(size);
	ret = usb_internal_control_msg(dev, pipe, dr, data, size, timeout);
	kfree(dr);
	return ret;
}
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 | Total | 130 | 100.00% | 5 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_control_msg);
/**
 * usb_interrupt_msg - Builds an interrupt urb, sends it off and waits for completion
 * @usb_dev: pointer to the usb device to send the message to
 * @pipe: endpoint "pipe" to send the message to
 * @data: pointer to the data to send
 * @len: length in bytes of the data to send
 * @actual_length: pointer to a location to put the actual length transferred
 *      in bytes
 * @timeout: time in msecs to wait for the message to complete before
 *      timing out (if 0 the wait is forever)
 *
 * Context: !in_interrupt ()
 *
 * This function sends a simple interrupt message to a specified endpoint and
 * waits for the message to complete, or timeout.
 *
 * Don't use this function from within an interrupt context, like a bottom half
 * handler.  If you need an asynchronous message, or need to send a message
 * from within interrupt context, use usb_submit_urb() If a thread in your
 * driver uses this call, make sure your disconnect() method can wait for it to
 * complete.  Since you don't have a handle on the URB used, you can't cancel
 * the request.
 *
 * Return:
 * If successful, 0. Otherwise a negative error number. The number of actual
 * bytes transferred will be stored in the @actual_length parameter.
 */
int usb_interrupt_msg(struct usb_device *usb_dev, unsigned int pipe,
		      void *data, int len, int *actual_length, int timeout)
{
	return usb_bulk_msg(usb_dev, pipe, data, len, actual_length, timeout);
}
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EXPORT_SYMBOL_GPL(usb_interrupt_msg);
/**
 * usb_bulk_msg - Builds a bulk urb, sends it off and waits for completion
 * @usb_dev: pointer to the usb device to send the message to
 * @pipe: endpoint "pipe" to send the message to
 * @data: pointer to the data to send
 * @len: length in bytes of the data to send
 * @actual_length: pointer to a location to put the actual length transferred
 *      in bytes
 * @timeout: time in msecs to wait for the message to complete before
 *      timing out (if 0 the wait is forever)
 *
 * Context: !in_interrupt ()
 *
 * This function sends a simple bulk message to a specified endpoint
 * and waits for the message to complete, or timeout.
 *
 * Don't use this function from within an interrupt context, like a bottom half
 * handler.  If you need an asynchronous message, or need to send a message
 * from within interrupt context, use usb_submit_urb() If a thread in your
 * driver uses this call, make sure your disconnect() method can wait for it to
 * complete.  Since you don't have a handle on the URB used, you can't cancel
 * the request.
 *
 * Because there is no usb_interrupt_msg() and no USBDEVFS_INTERRUPT ioctl,
 * users are forced to abuse this routine by using it to submit URBs for
 * interrupt endpoints.  We will take the liberty of creating an interrupt URB
 * (with the default interval) if the target is an interrupt endpoint.
 *
 * Return:
 * If successful, 0. Otherwise a negative error number. The number of actual
 * bytes transferred will be stored in the @actual_length parameter.
 *
 */
int usb_bulk_msg(struct usb_device *usb_dev, unsigned int pipe,
		 void *data, int len, int *actual_length, int timeout)
{
	struct urb *urb;
	struct usb_host_endpoint *ep;
	ep = usb_pipe_endpoint(usb_dev, pipe);
	if (!ep || len < 0)
		return -EINVAL;
	urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!urb)
		return -ENOMEM;
	if ((ep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK) ==
			USB_ENDPOINT_XFER_INT) {
		pipe = (pipe & ~(3 << 30)) | (PIPE_INTERRUPT << 30);
		usb_fill_int_urb(urb, usb_dev, pipe, data, len,
				usb_api_blocking_completion, NULL,
				ep->desc.bInterval);
	} else
		usb_fill_bulk_urb(urb, usb_dev, pipe, data, len,
				usb_api_blocking_completion, NULL);
	return usb_start_wait_urb(urb, timeout, actual_length);
}
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 | Total | 164 | 100.00% | 6 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_bulk_msg);
/*-------------------------------------------------------------------*/
static void sg_clean(struct usb_sg_request *io)
{
	if (io->urbs) {
		while (io->entries--)
			usb_free_urb(io->urbs[io->entries]);
		kfree(io->urbs);
		io->urbs = NULL;
	}
	io->dev = NULL;
}
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static void sg_complete(struct urb *urb)
{
	struct usb_sg_request *io = urb->context;
	int status = urb->status;
	spin_lock(&io->lock);
	/* In 2.5 we require hcds' endpoint queues not to progress after fault
         * reports, until the completion callback (this!) returns.  That lets
         * device driver code (like this routine) unlink queued urbs first,
         * if it needs to, since the HC won't work on them at all.  So it's
         * not possible for page N+1 to overwrite page N, and so on.
         *
         * That's only for "hard" faults; "soft" faults (unlinks) sometimes
         * complete before the HCD can get requests away from hardware,
         * though never during cleanup after a hard fault.
         */
	if (io->status
			&& (io->status != -ECONNRESET
				|| status != -ECONNRESET)
			&& urb->actual_length) {
		dev_err(io->dev->bus->controller,
			"dev %s ep%d%s scatterlist error %d/%d\n",
			io->dev->devpath,
			usb_endpoint_num(&urb->ep->desc),
			usb_urb_dir_in(urb) ? "in" : "out",
			status, io->status);
		/* BUG (); */
	}
	if (io->status == 0 && status && status != -ECONNRESET) {
		int i, found, retval;
		io->status = status;
		/* the previous urbs, and this one, completed already.
                 * unlink pending urbs so they won't rx/tx bad data.
                 * careful: unlink can sometimes be synchronous...
                 */
		spin_unlock(&io->lock);
		for (i = 0, found = 0; i < io->entries; i++) {
			if (!io->urbs[i])
				continue;
			if (found) {
				usb_block_urb(io->urbs[i]);
				retval = usb_unlink_urb(io->urbs[i]);
				if (retval != -EINPROGRESS &&
				    retval != -ENODEV &&
				    retval != -EBUSY &&
				    retval != -EIDRM)
					dev_err(&io->dev->dev,
						"%s, unlink --> %d\n",
						__func__, retval);
			} else if (urb == io->urbs[i])
				found = 1;
		}
		spin_lock(&io->lock);
	}
	/* on the last completion, signal usb_sg_wait() */
	io->bytes += urb->actual_length;
	io->count--;
	if (!io->count)
		complete(&io->complete);
	spin_unlock(&io->lock);
}
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 | Total | 305 | 100.00% | 13 | 100.00% | 
/**
 * usb_sg_init - initializes scatterlist-based bulk/interrupt I/O request
 * @io: request block being initialized.  until usb_sg_wait() returns,
 *      treat this as a pointer to an opaque block of memory,
 * @dev: the usb device that will send or receive the data
 * @pipe: endpoint "pipe" used to transfer the data
 * @period: polling rate for interrupt endpoints, in frames or
 *      (for high speed endpoints) microframes; ignored for bulk
 * @sg: scatterlist entries
 * @nents: how many entries in the scatterlist
 * @length: how many bytes to send from the scatterlist, or zero to
 *      send every byte identified in the list.
 * @mem_flags: SLAB_* flags affecting memory allocations in this call
 *
 * This initializes a scatter/gather request, allocating resources such as
 * I/O mappings and urb memory (except maybe memory used by USB controller
 * drivers).
 *
 * The request must be issued using usb_sg_wait(), which waits for the I/O to
 * complete (or to be canceled) and then cleans up all resources allocated by
 * usb_sg_init().
 *
 * The request may be canceled with usb_sg_cancel(), either before or after
 * usb_sg_wait() is called.
 *
 * Return: Zero for success, else a negative errno value.
 */
int usb_sg_init(struct usb_sg_request *io, struct usb_device *dev,
		unsigned pipe, unsigned	period, struct scatterlist *sg,
		int nents, size_t length, gfp_t mem_flags)
{
	int i;
	int urb_flags;
	int use_sg;
	if (!io || !dev || !sg
			|| usb_pipecontrol(pipe)
			|| usb_pipeisoc(pipe)
			|| nents <= 0)
		return -EINVAL;
	spin_lock_init(&io->lock);
	io->dev = dev;
	io->pipe = pipe;
	if (dev->bus->sg_tablesize > 0) {
		use_sg = true;
		io->entries = 1;
	} else {
		use_sg = false;
		io->entries = nents;
	}
	/* initialize all the urbs we'll use */
	io->urbs = kmalloc(io->entries * sizeof(*io->urbs), mem_flags);
	if (!io->urbs)
		goto nomem;
	urb_flags = URB_NO_INTERRUPT;
	if (usb_pipein(pipe))
		urb_flags |= URB_SHORT_NOT_OK;
	for_each_sg(sg, sg, io->entries, i) {
		struct urb *urb;
		unsigned len;
		urb = usb_alloc_urb(0, mem_flags);
		if (!urb) {
			io->entries = i;
			goto nomem;
		}
		io->urbs[i] = urb;
		urb->dev = NULL;
		urb->pipe = pipe;
		urb->interval = period;
		urb->transfer_flags = urb_flags;
		urb->complete = sg_complete;
		urb->context = io;
		urb->sg = sg;
		if (use_sg) {
			/* There is no single transfer buffer */
			urb->transfer_buffer = NULL;
			urb->num_sgs = nents;
			/* A length of zero means transfer the whole sg list */
			len = length;
			if (len == 0) {
				struct scatterlist	*sg2;
				int			j;
				for_each_sg(sg, sg2, nents, j)
					len += sg2->length;
			}
		} else {
			/*
                         * Some systems can't use DMA; they use PIO instead.
                         * For their sakes, transfer_buffer is set whenever
                         * possible.
                         */
			if (!PageHighMem(sg_page(sg)))
				urb->transfer_buffer = sg_virt(sg);
			else
				urb->transfer_buffer = NULL;
			len = sg->length;
			if (length) {
				len = min_t(size_t, len, length);
				length -= len;
				if (length == 0)
					io->entries = i + 1;
			}
		}
		urb->transfer_buffer_length = len;
	}
	io->urbs[--i]->transfer_flags &= ~URB_NO_INTERRUPT;
	/* transaction state */
	io->count = io->entries;
	io->status = 0;
	io->bytes = 0;
	init_completion(&io->complete);
	return 0;
nomem:
	sg_clean(io);
	return -ENOMEM;
}
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EXPORT_SYMBOL_GPL(usb_sg_init);
/**
 * usb_sg_wait - synchronously execute scatter/gather request
 * @io: request block handle, as initialized with usb_sg_init().
 *      some fields become accessible when this call returns.
 * Context: !in_interrupt ()
 *
 * This function blocks until the specified I/O operation completes.  It
 * leverages the grouping of the related I/O requests to get good transfer
 * rates, by queueing the requests.  At higher speeds, such queuing can
 * significantly improve USB throughput.
 *
 * There are three kinds of completion for this function.
 * (1) success, where io->status is zero.  The number of io->bytes
 *     transferred is as requested.
 * (2) error, where io->status is a negative errno value.  The number
 *     of io->bytes transferred before the error is usually less
 *     than requested, and can be nonzero.
 * (3) cancellation, a type of error with status -ECONNRESET that
 *     is initiated by usb_sg_cancel().
 *
 * When this function returns, all memory allocated through usb_sg_init() or
 * this call will have been freed.  The request block parameter may still be
 * passed to usb_sg_cancel(), or it may be freed.  It could also be
 * reinitialized and then reused.
 *
 * Data Transfer Rates:
 *
 * Bulk transfers are valid for full or high speed endpoints.
 * The best full speed data rate is 19 packets of 64 bytes each
 * per frame, or 1216 bytes per millisecond.
 * The best high speed data rate is 13 packets of 512 bytes each
 * per microframe, or 52 KBytes per millisecond.
 *
 * The reason to use interrupt transfers through this API would most likely
 * be to reserve high speed bandwidth, where up to 24 KBytes per millisecond
 * could be transferred.  That capability is less useful for low or full
 * speed interrupt endpoints, which allow at most one packet per millisecond,
 * of at most 8 or 64 bytes (respectively).
 *
 * It is not necessary to call this function to reserve bandwidth for devices
 * under an xHCI host controller, as the bandwidth is reserved when the
 * configuration or interface alt setting is selected.
 */
void usb_sg_wait(struct usb_sg_request *io)
{
	int i;
	int entries = io->entries;
	/* queue the urbs.  */
	spin_lock_irq(&io->lock);
	i = 0;
	while (i < entries && !io->status) {
		int retval;
		io->urbs[i]->dev = io->dev;
		spin_unlock_irq(&io->lock);
		retval = usb_submit_urb(io->urbs[i], GFP_NOIO);
		switch (retval) {
			/* maybe we retrying will recover */
		case -ENXIO:	/* hc didn't queue this one */
		case -EAGAIN:
		case -ENOMEM:
			retval = 0;
			yield();
			break;
			/* no error? continue immediately.
                         *
                         * NOTE: to work better with UHCI (4K I/O buffer may
                         * need 3K of TDs) it may be good to limit how many
                         * URBs are queued at once; N milliseconds?
                         */
		case 0:
			++i;
			cpu_relax();
			break;
			/* fail any uncompleted urbs */
		default:
			io->urbs[i]->status = retval;
			dev_dbg(&io->dev->dev, "%s, submit --> %d\n",
				__func__, retval);
			usb_sg_cancel(io);
		}
		spin_lock_irq(&io->lock);
		if (retval && (io->status == 0 || io->status == -ECONNRESET))
			io->status = retval;
	}
	io->count -= entries - i;
	if (io->count == 0)
		complete(&io->complete);
	spin_unlock_irq(&io->lock);
	/* OK, yes, this could be packaged as non-blocking.
         * So could the submit loop above ... but it's easier to
         * solve neither problem than to solve both!
         */
	wait_for_completion(&io->complete);
	sg_clean(io);
}
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| harvey harrison | harvey harrison | 1 | 0.42% | 1 | 10.00% | 
 | Total | 236 | 100.00% | 10 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_sg_wait);
/**
 * usb_sg_cancel - stop scatter/gather i/o issued by usb_sg_wait()
 * @io: request block, initialized with usb_sg_init()
 *
 * This stops a request after it has been started by usb_sg_wait().
 * It can also prevents one initialized by usb_sg_init() from starting,
 * so that call just frees resources allocated to the request.
 */
void usb_sg_cancel(struct usb_sg_request *io)
{
	unsigned long flags;
	int i, retval;
	spin_lock_irqsave(&io->lock, flags);
	if (io->status) {
		spin_unlock_irqrestore(&io->lock, flags);
		return;
	}
	/* shut everything down */
	io->status = -ECONNRESET;
	spin_unlock_irqrestore(&io->lock, flags);
	for (i = io->entries - 1; i >= 0; --i) {
		usb_block_urb(io->urbs[i]);
		retval = usb_unlink_urb(io->urbs[i]);
		if (retval != -EINPROGRESS
		    && retval != -ENODEV
		    && retval != -EBUSY
		    && retval != -EIDRM)
			dev_warn(&io->dev->dev, "%s, unlink --> %d\n",
				 __func__, retval);
	}
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| david brownell | david brownell | 84 | 57.93% | 3 | 33.33% | 
| david mosberger | david mosberger | 32 | 22.07% | 2 | 22.22% | 
| patrick mochel | patrick mochel | 17 | 11.72% | 1 | 11.11% | 
| alan stern | alan stern | 10 | 6.90% | 1 | 11.11% | 
| greg kroah-hartman | greg kroah-hartman | 1 | 0.69% | 1 | 11.11% | 
| harvey harrison | harvey harrison | 1 | 0.69% | 1 | 11.11% | 
 | Total | 145 | 100.00% | 9 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_sg_cancel);
/*-------------------------------------------------------------------*/
/**
 * usb_get_descriptor - issues a generic GET_DESCRIPTOR request
 * @dev: the device whose descriptor is being retrieved
 * @type: the descriptor type (USB_DT_*)
 * @index: the number of the descriptor
 * @buf: where to put the descriptor
 * @size: how big is "buf"?
 * Context: !in_interrupt ()
 *
 * Gets a USB descriptor.  Convenience functions exist to simplify
 * getting some types of descriptors.  Use
 * usb_get_string() or usb_string() for USB_DT_STRING.
 * Device (USB_DT_DEVICE) and configuration descriptors (USB_DT_CONFIG)
 * are part of the device structure.
 * In addition to a number of USB-standard descriptors, some
 * devices also use class-specific or vendor-specific descriptors.
 *
 * This call is synchronous, and may not be used in an interrupt context.
 *
 * Return: The number of bytes received on success, or else the status code
 * returned by the underlying usb_control_msg() call.
 */
int usb_get_descriptor(struct usb_device *dev, unsigned char type,
		       unsigned char index, void *buf, int size)
{
	int i;
	int result;
	memset(buf, 0, size);	/* Make sure we parse really received data */
	for (i = 0; i < 3; ++i) {
		/* retry on length 0 or error; some devices are flakey */
		result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
				USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
				(type << 8) + index, 0, buf, size,
				USB_CTRL_GET_TIMEOUT);
		if (result <= 0 && result != -ETIMEDOUT)
			continue;
		if (result > 1 && ((u8 *)buf)[1] != type) {
			result = -ENODATA;
			continue;
		}
		break;
	}
	return result;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| patrick mochel | patrick mochel | 84 | 62.69% | 1 | 14.29% | 
| david brownell | david brownell | 25 | 18.66% | 1 | 14.29% | 
| alan stern | alan stern | 23 | 17.16% | 3 | 42.86% | 
| greg kroah-hartman | greg kroah-hartman | 2 | 1.49% | 2 | 28.57% | 
 | Total | 134 | 100.00% | 7 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_get_descriptor);
/**
 * usb_get_string - gets a string descriptor
 * @dev: the device whose string descriptor is being retrieved
 * @langid: code for language chosen (from string descriptor zero)
 * @index: the number of the descriptor
 * @buf: where to put the string
 * @size: how big is "buf"?
 * Context: !in_interrupt ()
 *
 * Retrieves a string, encoded using UTF-16LE (Unicode, 16 bits per character,
 * in little-endian byte order).
 * The usb_string() function will often be a convenient way to turn
 * these strings into kernel-printable form.
 *
 * Strings may be referenced in device, configuration, interface, or other
 * descriptors, and could also be used in vendor-specific ways.
 *
 * This call is synchronous, and may not be used in an interrupt context.
 *
 * Return: The number of bytes received on success, or else the status code
 * returned by the underlying usb_control_msg() call.
 */
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) {
		/* retry on length 0 or stall; some devices are flakey */
		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_CTRL_GET_TIMEOUT);
		if (result == 0 || result == -EPIPE)
			continue;
		if (result > 1 && ((u8 *) buf)[1] != USB_DT_STRING) {
			result = -ENODATA;
			continue;
		}
		break;
	}
	return result;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 67 | 53.60% | 2 | 50.00% | 
| patrick mochel | patrick mochel | 57 | 45.60% | 1 | 25.00% | 
| adrian bunk | adrian bunk | 1 | 0.80% | 1 | 25.00% | 
 | Total | 125 | 100.00% | 4 | 100.00% | 
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;
	}
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| duncan sands | duncan sands | 78 | 100.00% | 1 | 100.00% | 
 | Total | 78 | 100.00% | 1 | 100.00% | 
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 */
	if (dev->quirks & USB_QUIRK_STRING_FETCH_255)
		rc = -EIO;
	else
		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 = (rc < 0 ? rc : -EINVAL);
	return rc;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 102 | 55.14% | 2 | 40.00% | 
| duncan sands | duncan sands | 44 | 23.78% | 1 | 20.00% | 
| patrick mochel | patrick mochel | 25 | 13.51% | 1 | 20.00% | 
| oliver neukum | oliver neukum | 14 | 7.57% | 1 | 20.00% | 
 | Total | 185 | 100.00% | 5 | 100.00% | 
static int usb_get_langid(struct usb_device *dev, unsigned char *tbuf)
{
	int err;
	if (dev->have_langid)
		return 0;
	if (dev->string_langid < 0)
		return -EPIPE;
	err = usb_string_sub(dev, 0, 0, tbuf);
	/* If the string was reported but is malformed, default to english
         * (0x0409) */
	if (err == -ENODATA || (err > 0 && err < 4)) {
		dev->string_langid = 0x0409;
		dev->have_langid = 1;
		dev_err(&dev->dev,
			"language id specifier not provided by device, defaulting to English\n");
		return 0;
	}
	/* In case of all other errors, we assume the device is not able to
         * deal with strings at all. Set string_langid to -1 in order to
         * prevent any string to be retrieved from the device */
	if (err < 0) {
		dev_err(&dev->dev, "string descriptor 0 read error: %d\n",
					err);
		dev->string_langid = -1;
		return -EPIPE;
	}
	/* always use the first langid listed */
	dev->string_langid = tbuf[2] | (tbuf[3] << 8);
	dev->have_langid = 1;
	dev_dbg(&dev->dev, "default language 0x%04x\n",
				dev->string_langid);
	return 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 72 | 41.86% | 2 | 33.33% | 
| daniel mack | daniel mack | 65 | 37.79% | 1 | 16.67% | 
| patrick mochel | patrick mochel | 30 | 17.44% | 1 | 16.67% | 
| david brownell | david brownell | 4 | 2.33% | 1 | 16.67% | 
| scot doyle | scot doyle | 1 | 0.58% | 1 | 16.67% | 
 | Total | 172 | 100.00% | 6 | 100.00% | 
/**
 * usb_string - returns UTF-8 version of a string descriptor
 * @dev: the device whose string descriptor is being retrieved
 * @index: the number of the descriptor
 * @buf: where to put the string
 * @size: how big is "buf"?
 * Context: !in_interrupt ()
 *
 * This converts the UTF-16LE encoded strings returned by devices, from
 * usb_get_string_descriptor(), to null-terminated UTF-8 encoded ones
 * that are more usable in most kernel contexts.  Note that this function
 * chooses strings in the first language supported by the device.
 *
 * This call is synchronous, and may not be used in an interrupt context.
 *
 * Return: length of the string (>= 0) or usb_control_msg status (< 0).
 */
int usb_string(struct usb_device *dev, int index, char *buf, size_t size)
{
	unsigned char *tbuf;
	int err;
	if (dev->state == USB_STATE_SUSPENDED)
		return -EHOSTUNREACH;
	if (size <= 0 || !buf || !index)
		return -EINVAL;
	buf[0] = 0;
	tbuf = kmalloc(256, GFP_NOIO);
	if (!tbuf)
		return -ENOMEM;
	err = usb_get_langid(dev, tbuf);
	if (err < 0)
		goto errout;
	err = usb_string_sub(dev, dev->string_langid, index, tbuf);
	if (err < 0)
		goto errout;
	size--;		/* leave room for trailing NULL char in output buffer */
	err = utf16s_to_utf8s((wchar_t *) &tbuf[2], (err - 2) / 2,
			UTF16_LITTLE_ENDIAN, buf, size);
	buf[err] = 0;
	if (tbuf[1] != USB_DT_STRING)
		dev_dbg(&dev->dev,
			"wrong descriptor type %02x for string %d (\"%s\")\n",
			tbuf[1], index, buf);
 errout:
	kfree(tbuf);
	return err;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| daniel mack | daniel mack | 98 | 48.76% | 2 | 28.57% | 
| alan stern | alan stern | 59 | 29.35% | 3 | 42.86% | 
| duncan sands | duncan sands | 28 | 13.93% | 1 | 14.29% | 
| clemens ladisch | clemens ladisch | 16 | 7.96% | 1 | 14.29% | 
 | Total | 201 | 100.00% | 7 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_string);
/* one UTF-8-encoded 16-bit character has at most three bytes */
#define MAX_USB_STRING_SIZE (127 * 3 + 1)
/**
 * usb_cache_string - read a string descriptor and cache it for later use
 * @udev: the device whose string descriptor is being read
 * @index: the descriptor index
 *
 * Return: A pointer to a kmalloc'ed buffer containing the descriptor string,
 * or %NULL if the index is 0 or the string could not be read.
 */
char *usb_cache_string(struct usb_device *udev, int index)
{
	char *buf;
	char *smallbuf = NULL;
	int len;
	if (index <= 0)
		return NULL;
	buf = kmalloc(MAX_USB_STRING_SIZE, GFP_NOIO);
	if (buf) {
		len = usb_string(udev, index, buf, MAX_USB_STRING_SIZE);
		if (len > 0) {
			smallbuf = kmalloc(++len, GFP_NOIO);
			if (!smallbuf)
				return buf;
			memcpy(smallbuf, buf, len);
		}
		kfree(buf);
	}
	return smallbuf;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 85 | 79.44% | 1 | 25.00% | 
| greg kroah-hartman | greg kroah-hartman | 18 | 16.82% | 1 | 25.00% | 
| oliver neukum | oliver neukum | 2 | 1.87% | 1 | 25.00% | 
| clemens ladisch | clemens ladisch | 2 | 1.87% | 1 | 25.00% | 
 | Total | 107 | 100.00% | 4 | 100.00% | 
/*
 * usb_get_device_descriptor - (re)reads the device descriptor (usbcore)
 * @dev: the device whose device descriptor is being updated
 * @size: how much of the descriptor to read
 * Context: !in_interrupt ()
 *
 * Updates the copy of the device descriptor stored in the device structure,
 * which dedicates space for this purpose.
 *
 * Not exported, only for use by the core.  If drivers really want to read
 * the device descriptor directly, they can call usb_get_descriptor() with
 * type = USB_DT_DEVICE and index = 0.
 *
 * This call is synchronous, and may not be used in an interrupt context.
 *
 * Return: The number of bytes received on success, or else the status code
 * returned by the underlying usb_control_msg() call.
 */
int usb_get_device_descriptor(struct usb_device *dev, unsigned int size)
{
	struct usb_device_descriptor *desc;
	int ret;
	if (size > sizeof(*desc))
		return -EINVAL;
	desc = kmalloc(sizeof(*desc), GFP_NOIO);
	if (!desc)
		return -ENOMEM;
	ret = usb_get_descriptor(dev, USB_DT_DEVICE, 0, desc, size);
	if (ret >= 0)
		memcpy(&dev->descriptor, desc, size);
	kfree(desc);
	return ret;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 93 | 93.94% | 4 | 80.00% | 
| david brownell | david brownell | 6 | 6.06% | 1 | 20.00% | 
 | Total | 99 | 100.00% | 5 | 100.00% | 
/**
 * usb_get_status - issues a GET_STATUS call
 * @dev: the device whose status is being checked
 * @type: USB_RECIP_*; for device, interface, or endpoint
 * @target: zero (for device), else interface or endpoint number
 * @data: pointer to two bytes of bitmap data
 * Context: !in_interrupt ()
 *
 * Returns device, interface, or endpoint status.  Normally only of
 * interest to see if the device is self powered, or has enabled the
 * remote wakeup facility; or whether a bulk or interrupt endpoint
 * is halted ("stalled").
 *
 * Bits in these status bitmaps are set using the SET_FEATURE request,
 * and cleared using the CLEAR_FEATURE request.  The usb_clear_halt()
 * function should be used to clear halt ("stall") status.
 *
 * This call is synchronous, and may not be used in an interrupt context.
 *
 * Returns 0 and the status value in *@data (in host byte order) on success,
 * or else the status code from the underlying usb_control_msg() call.
 */
int usb_get_status(struct usb_device *dev, int type, int target, void *data)
{
	int ret;
	__le16 *status = kmalloc(sizeof(*status), GFP_KERNEL);
	if (!status)
		return -ENOMEM;
	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
		USB_REQ_GET_STATUS, USB_DIR_IN | type, 0, target, status,
		sizeof(*status), USB_CTRL_GET_TIMEOUT);
	if (ret == 2) {
		*(u16 *) data = le16_to_cpu(*status);
		ret = 0;
	} else if (ret >= 0) {
		ret = -EIO;
	}
	kfree(status);
	return ret;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 74 | 57.81% | 4 | 66.67% | 
| dale farnsworth | dale farnsworth | 51 | 39.84% | 1 | 16.67% | 
| david brownell | david brownell | 3 | 2.34% | 1 | 16.67% | 
 | Total | 128 | 100.00% | 6 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_get_status);
/**
 * usb_clear_halt - tells device to clear endpoint halt/stall condition
 * @dev: device whose endpoint is halted
 * @pipe: endpoint "pipe" being cleared
 * Context: !in_interrupt ()
 *
 * This is used to clear halt conditions for bulk and interrupt endpoints,
 * as reported by URB completion status.  Endpoints that are halted are
 * sometimes referred to as being "stalled".  Such endpoints are unable
 * to transmit or receive data until the halt status is cleared.  Any URBs
 * queued for such an endpoint should normally be unlinked by the driver
 * before clearing the halt condition, as described in sections 5.7.5
 * and 5.8.5 of the USB 2.0 spec.
 *
 * Note that control and isochronous endpoints don't halt, although control
 * endpoints report "protocol stall" (for unsupported requests) using the
 * same status code used to report a true stall.
 *
 * This call is synchronous, and may not be used in an interrupt context.
 *
 * Return: Zero on success, or else the status code returned by the
 * underlying usb_control_msg() call.
 */
int usb_clear_halt(struct usb_device *dev, int pipe)
{
	int result;
	int endp = usb_pipeendpoint(pipe);
	if (usb_pipein(pipe))
		endp |= USB_DIR_IN;
	/* we don't care if it wasn't halted first. in fact some devices
         * (like some ibmcam model 1 units) seem to expect hosts to make
         * this request for iso endpoints, which can't halt!
         */
	result = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
		USB_REQ_CLEAR_FEATURE, USB_RECIP_ENDPOINT,
		USB_ENDPOINT_HALT, endp, NULL, 0,
		USB_CTRL_SET_TIMEOUT);
	/* don't un-halt or force to DATA0 except on success */
	if (result < 0)
		return result;
	/* NOTE:  seems like Microsoft and Apple don't bother verifying
         * the clear "took", so some devices could lock up if you check...
         * such as the Hagiwara FlashGate DUAL.  So we won't bother.
         *
         * NOTE:  make sure the logic here doesn't diverge much from
         * the copy in usb-storage, for as long as we need two copies.
         */
	usb_reset_endpoint(dev, endp);
	return 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 83 | 97.65% | 2 | 66.67% | 
| david vrabel | david vrabel | 2 | 2.35% | 1 | 33.33% | 
 | Total | 85 | 100.00% | 3 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_clear_halt);
static int create_intf_ep_devs(struct usb_interface *intf)
{
	struct usb_device *udev = interface_to_usbdev(intf);
	struct usb_host_interface *alt = intf->cur_altsetting;
	int i;
	if (intf->ep_devs_created || intf->unregistering)
		return 0;
	for (i = 0; i < alt->desc.bNumEndpoints; ++i)
		(void) usb_create_ep_devs(&intf->dev, &alt->endpoint[i], udev);
	intf->ep_devs_created = 1;
	return 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 93 | 100.00% | 1 | 100.00% | 
 | Total | 93 | 100.00% | 1 | 100.00% | 
static void remove_intf_ep_devs(struct usb_interface *intf)
{
	struct usb_host_interface *alt = intf->cur_altsetting;
	int i;
	if (!intf->ep_devs_created)
		return;
	for (i = 0; i < alt->desc.bNumEndpoints; ++i)
		usb_remove_ep_devs(&alt->endpoint[i]);
	intf->ep_devs_created = 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 65 | 100.00% | 1 | 100.00% | 
 | Total | 65 | 100.00% | 1 | 100.00% | 
/**
 * usb_disable_endpoint -- Disable an endpoint by address
 * @dev: the device whose endpoint is being disabled
 * @epaddr: the endpoint's address.  Endpoint number for output,
 *      endpoint number + USB_DIR_IN for input
 * @reset_hardware: flag to erase any endpoint state stored in the
 *      controller hardware
 *
 * Disables the endpoint for URB submission and nukes all pending URBs.
 * If @reset_hardware is set then also deallocates hcd/hardware state
 * for the endpoint.
 */
void usb_disable_endpoint(struct usb_device *dev, unsigned int epaddr,
		bool reset_hardware)
{
	unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK;
	struct usb_host_endpoint *ep;
	if (!dev)
		return;
	if (usb_endpoint_out(epaddr)) {
		ep = dev->ep_out[epnum];
		if (reset_hardware)
			dev->ep_out[epnum] = NULL;
	} else {
		ep = dev->ep_in[epnum];
		if (reset_hardware)
			dev->ep_in[epnum] = NULL;
	}
	if (ep) {
		ep->enabled = 0;
		usb_hcd_flush_endpoint(dev, ep);
		if (reset_hardware)
			usb_hcd_disable_endpoint(dev, ep);
	}
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| david brownell | david brownell | 69 | 56.56% | 1 | 16.67% | 
| alan stern | alan stern | 53 | 43.44% | 5 | 83.33% | 
 | Total | 122 | 100.00% | 6 | 100.00% | 
/**
 * usb_reset_endpoint - Reset an endpoint's state.
 * @dev: the device whose endpoint is to be reset
 * @epaddr: the endpoint's address.  Endpoint number for output,
 *      endpoint number + USB_DIR_IN for input
 *
 * Resets any host-side endpoint state such as the toggle bit,
 * sequence number or current window.
 */
void usb_reset_endpoint(struct usb_device *dev, unsigned int epaddr)
{
	unsigned int epnum = epaddr & USB_ENDPOINT_NUMBER_MASK;
	struct usb_host_endpoint *ep;
	if (usb_endpoint_out(epaddr))
		ep = dev->ep_out[epnum];
	else
		ep = dev->ep_in[epnum];
	if (ep)
		usb_hcd_reset_endpoint(dev, ep);
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| david vrabel | david vrabel | 64 | 100.00% | 1 | 100.00% | 
 | Total | 64 | 100.00% | 1 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_reset_endpoint);
/**
 * usb_disable_interface -- Disable all endpoints for an interface
 * @dev: the device whose interface is being disabled
 * @intf: pointer to the interface descriptor
 * @reset_hardware: flag to erase any endpoint state stored in the
 *      controller hardware
 *
 * Disables all the endpoints for the interface's current altsetting.
 */
void usb_disable_interface(struct usb_device *dev, struct usb_interface *intf,
		bool reset_hardware)
{
	struct usb_host_interface *alt = intf->cur_altsetting;
	int i;
	for (i = 0; i < alt->desc.bNumEndpoints; ++i) {
		usb_disable_endpoint(dev,
				alt->endpoint[i].desc.bEndpointAddress,
				reset_hardware);
	}
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 67 | 100.00% | 4 | 100.00% | 
 | Total | 67 | 100.00% | 4 | 100.00% | 
/**
 * usb_disable_device - Disable all the endpoints for a USB device
 * @dev: the device whose endpoints are being disabled
 * @skip_ep0: 0 to disable endpoint 0, 1 to skip it.
 *
 * Disables all the device's endpoints, potentially including endpoint 0.
 * Deallocates hcd/hardware state for the endpoints (nuking all or most
 * pending urbs) and usbcore state for the interfaces, so that usbcore
 * must usb_set_configuration() before any interfaces could be used.
 */
void usb_disable_device(struct usb_device *dev, int skip_ep0)
{
	int i;
	struct usb_hcd *hcd = bus_to_hcd(dev->bus);
	/* getting rid of interfaces will disconnect
         * any drivers bound to them (a key side effect)
         */
	if (dev->actconfig) {
		/*
                 * FIXME: In order to avoid self-deadlock involving the
                 * bandwidth_mutex, we have to mark all the interfaces
                 * before unregistering any of them.
                 */
		for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++)
			dev->actconfig->interface[i]->unregistering = 1;
		for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
			struct usb_interface	*interface;
			/* remove this interface if it has been registered */
			interface = dev->actconfig->interface[i];
			if (!device_is_registered(&interface->dev))
				continue;
			dev_dbg(&dev->dev, "unregistering interface %s\n",
				dev_name(&interface->dev));
			remove_intf_ep_devs(interface);
			device_del(&interface->dev);
		}
		/* Now that the interfaces are unbound, nobody should
                 * try to access them.
                 */
		for (i = 0; i < dev->actconfig->desc.bNumInterfaces; i++) {
			put_device(&dev->actconfig->interface[i]->dev);
			dev->actconfig->interface[i] = NULL;
		}
		if (dev->usb2_hw_lpm_enabled == 1)
			usb_set_usb2_hardware_lpm(dev, 0);
		usb_unlocked_disable_lpm(dev);
		usb_disable_ltm(dev);
		dev->actconfig = NULL;
		if (dev->state == USB_STATE_CONFIGURED)
			usb_set_device_state(dev, USB_STATE_ADDRESS);
	}
	dev_dbg(&dev->dev, "%s nuking %s URBs\n", __func__,
		skip_ep0 ? "non-ep0" : "all");
	if (hcd->driver->check_bandwidth) {
		/* First pass: Cancel URBs, leave endpoint pointers intact. */
		for (i = skip_ep0; i < 16; ++i) {
			usb_disable_endpoint(dev, i, false);
			usb_disable_endpoint(dev, i + USB_DIR_IN, false);
		}
		/* Remove endpoints from the host controller internal state */
		mutex_lock(hcd->bandwidth_mutex);
		usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL);
		mutex_unlock(hcd->bandwidth_mutex);
		/* Second pass: remove endpoint pointers */
	}
	for (i = skip_ep0; i < 16; ++i) {
		usb_disable_endpoint(dev, i, true);
		usb_disable_endpoint(dev, i + USB_DIR_IN, true);
	}
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 227 | 61.19% | 10 | 47.62% | 
| sarah sharp | sarah sharp | 96 | 25.88% | 4 | 19.05% | 
| patrick mochel | patrick mochel | 31 | 8.36% | 1 | 4.76% | 
| david brownell | david brownell | 12 | 3.23% | 4 | 19.05% | 
| kay sievers | kay sievers | 4 | 1.08% | 1 | 4.76% | 
| daniel ritz | daniel ritz | 1 | 0.27% | 1 | 4.76% | 
 | Total | 371 | 100.00% | 21 | 100.00% | 
/**
 * usb_enable_endpoint - Enable an endpoint for USB communications
 * @dev: the device whose interface is being enabled
 * @ep: the endpoint
 * @reset_ep: flag to reset the endpoint state
 *
 * Resets the endpoint state if asked, and sets dev->ep_{in,out} pointers.
 * For control endpoints, both the input and output sides are handled.
 */
void usb_enable_endpoint(struct usb_device *dev, struct usb_host_endpoint *ep,
		bool reset_ep)
{
	int epnum = usb_endpoint_num(&ep->desc);
	int is_out = usb_endpoint_dir_out(&ep->desc);
	int is_control = usb_endpoint_xfer_control(&ep->desc);
	if (reset_ep)
		usb_hcd_reset_endpoint(dev, ep);
	if (is_out || is_control)
		dev->ep_out[epnum] = ep;
	if (!is_out || is_control)
		dev->ep_in[epnum] = ep;
	ep->enabled = 1;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 58 | 58.59% | 3 | 50.00% | 
| david brownell | david brownell | 31 | 31.31% | 2 | 33.33% | 
| david vrabel | david vrabel | 10 | 10.10% | 1 | 16.67% | 
 | Total | 99 | 100.00% | 6 | 100.00% | 
/**
 * usb_enable_interface - Enable all the endpoints for an interface
 * @dev: the device whose interface is being enabled
 * @intf: pointer to the interface descriptor
 * @reset_eps: flag to reset the endpoints' state
 *
 * Enables all the endpoints for the interface's current altsetting.
 */
void usb_enable_interface(struct usb_device *dev,
		struct usb_interface *intf, bool reset_eps)
{
	struct usb_host_interface *alt = intf->cur_altsetting;
	int i;
	for (i = 0; i < alt->desc.bNumEndpoints; ++i)
		usb_enable_endpoint(dev, &alt->endpoint[i], reset_eps);
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 47 | 75.81% | 4 | 66.67% | 
| david brownell | david brownell | 13 | 20.97% | 1 | 16.67% | 
| david vrabel | david vrabel | 2 | 3.23% | 1 | 16.67% | 
 | Total | 62 | 100.00% | 6 | 100.00% | 
/**
 * usb_set_interface - Makes a particular alternate setting be current
 * @dev: the device whose interface is being updated
 * @interface: the interface being updated
 * @alternate: the setting being chosen.
 * Context: !in_interrupt ()
 *
 * This is used to enable data transfers on interfaces that may not
 * be enabled by default.  Not all devices support such configurability.
 * Only the driver bound to an interface may change its setting.
 *
 * Within any given configuration, each interface may have several
 * alternative settings.  These are often used to control levels of
 * bandwidth consumption.  For example, the default setting for a high
 * speed interrupt endpoint may not send more than 64 bytes per microframe,
 * while interrupt transfers of up to 3KBytes per microframe are legal.
 * Also, isochronous endpoints may never be part of an
 * interface's default setting.  To access such bandwidth, alternate
 * interface settings must be made current.
 *
 * Note that in the Linux USB subsystem, bandwidth associated with
 * an endpoint in a given alternate setting is not reserved until an URB
 * is submitted that needs that bandwidth.  Some other operating systems
 * allocate bandwidth early, when a configuration is chosen.
 *
 * This call is synchronous, and may not be used in an interrupt context.
 * Also, drivers must not change altsettings while urbs are scheduled for
 * endpoints in that interface; all such urbs must first be completed
 * (perhaps forced by unlinking).
 *
 * Return: Zero on success, or else the status code returned by the
 * underlying usb_control_msg() call.
 */
int usb_set_interface(struct usb_device *dev, int interface, int alternate)
{
	struct usb_interface *iface;
	struct usb_host_interface *alt;
	struct usb_hcd *hcd = bus_to_hcd(dev->bus);
	int i, ret, manual = 0;
	unsigned int epaddr;
	unsigned int pipe;
	if (dev->state == USB_STATE_SUSPENDED)
		return -EHOSTUNREACH;
	iface = usb_ifnum_to_if(dev, interface);
	if (!iface) {
		dev_dbg(&dev->dev, "selecting invalid interface %d\n",
			interface);
		return -EINVAL;
	}
	if (iface->unregistering)
		return -ENODEV;
	alt = usb_altnum_to_altsetting(iface, alternate);
	if (!alt) {
		dev_warn(&dev->dev, "selecting invalid altsetting %d\n",
			 alternate);
		return -EINVAL;
	}
	/* Make sure we have enough bandwidth for this alternate interface.
         * Remove the current alt setting and add the new alt setting.
         */
	mutex_lock(hcd->bandwidth_mutex);
	/* Disable LPM, and re-enable it once the new alt setting is installed,
         * so that the xHCI driver can recalculate the U1/U2 timeouts.
         */
	if (usb_disable_lpm(dev)) {
		dev_err(&iface->dev, "%s Failed to disable LPM\n.", __func__);
		mutex_unlock(hcd->bandwidth_mutex);
		return -ENOMEM;
	}
	/* Changing alt-setting also frees any allocated streams */
	for (i = 0; i < iface->cur_altsetting->desc.bNumEndpoints; i++)
		iface->cur_altsetting->endpoint[i].streams = 0;
	ret = usb_hcd_alloc_bandwidth(dev, NULL, iface->cur_altsetting, alt);
	if (ret < 0) {
		dev_info(&dev->dev, "Not enough bandwidth for altsetting %d\n",
				alternate);
		usb_enable_lpm(dev);
		mutex_unlock(hcd->bandwidth_mutex);
		return ret;
	}
	if (dev->quirks & USB_QUIRK_NO_SET_INTF)
		ret = -EPIPE;
	else
		ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
				   USB_REQ_SET_INTERFACE, USB_RECIP_INTERFACE,
				   alternate, interface, NULL, 0, 5000);
	/* 9.4.10 says devices don't need this and are free to STALL the
         * request if the interface only has one alternate setting.
         */
	if (ret == -EPIPE && iface->num_altsetting == 1) {
		dev_dbg(&dev->dev,
			"manual set_interface for iface %d, alt %d\n",
			interface, alternate);
		manual = 1;
	} else if (ret < 0) {
		/* Re-instate the old alt setting */
		usb_hcd_alloc_bandwidth(dev, NULL, alt, iface->cur_altsetting);
		usb_enable_lpm(dev);
		mutex_unlock(hcd->bandwidth_mutex);
		return ret;
	}
	mutex_unlock(hcd->bandwidth_mutex);
	/* FIXME drivers shouldn't need to replicate/bugfix the logic here
         * when they implement async or easily-killable versions of this or
         * other "should-be-internal" functions (like clear_halt).
         * should hcd+usbcore postprocess control requests?
         */
	/* prevent submissions using previous endpoint settings */
	if (iface->cur_altsetting != alt) {
		remove_intf_ep_devs(iface);
		usb_remove_sysfs_intf_files(iface);
	}
	usb_disable_interface(dev, iface, true);
	iface->cur_altsetting = alt;
	/* Now that the interface is installed, re-enable LPM. */
	usb_unlocked_enable_lpm(dev);
	/* If the interface only has one altsetting and the device didn't
         * accept the request, we attempt to carry out the equivalent action
         * by manually clearing the HALT feature for each endpoint in the
         * new altsetting.
         */
	if (manual) {
		for (i = 0; i < alt->desc.bNumEndpoints; i++) {
			epaddr = alt->endpoint[i].desc.bEndpointAddress;
			pipe = __create_pipe(dev,
					USB_ENDPOINT_NUMBER_MASK & epaddr) |
					(usb_endpoint_out(epaddr) ?
					USB_DIR_OUT : USB_DIR_IN);
			usb_clear_halt(dev, pipe);
		}
	}
	/* 9.1.1.5: reset toggles for all endpoints in the new altsetting
         *
         * Note:
         * Despite EP0 is always present in all interfaces/AS, the list of
         * endpoints from the descriptor does not contain EP0. Due to its
         * omnipresence one might expect EP0 being considered "affected" by
         * any SetInterface request and hence assume toggles need to be reset.
         * However, EP0 toggles are re-synced for every individual transfer
         * during the SETUP stage - hence EP0 toggles are "don't care" here.
         * (Likewise, EP0 never "halts" on well designed devices.)
         */
	usb_enable_interface(dev, iface, true);
	if (device_is_registered(&iface->dev)) {
		usb_create_sysfs_intf_files(iface);
		create_intf_ep_devs(iface);
	}
	return 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 274 | 51.50% | 15 | 57.69% | 
| sarah sharp | sarah sharp | 144 | 27.07% | 2 | 7.69% | 
| patrick mochel | patrick mochel | 47 | 8.83% | 1 | 3.85% | 
| hans de goede | hans de goede | 36 | 6.77% | 1 | 3.85% | 
| greg kroah-hartman | greg kroah-hartman | 18 | 3.38% | 2 | 7.69% | 
| david brownell | david brownell | 11 | 2.07% | 3 | 11.54% | 
| thadeu lima de souza cascardo | thadeu lima de souza cascardo | 1 | 0.19% | 1 | 3.85% | 
| nishanth aravamudan | nishanth aravamudan | 1 | 0.19% | 1 | 3.85% | 
 | Total | 532 | 100.00% | 26 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_set_interface);
/**
 * usb_reset_configuration - lightweight device reset
 * @dev: the device whose configuration is being reset
 *
 * This issues a standard SET_CONFIGURATION request to the device using
 * the current configuration.  The effect is to reset most USB-related
 * state in the device, including interface altsettings (reset to zero),
 * endpoint halts (cleared), and endpoint state (only for bulk and interrupt
 * endpoints).  Other usbcore state is unchanged, including bindings of
 * usb device drivers to interfaces.
 *
 * Because this affects multiple interfaces, avoid using this with composite
 * (multi-interface) devices.  Instead, the driver for each interface may
 * use usb_set_interface() on the interfaces it claims.  Be careful though;
 * some devices don't support the SET_INTERFACE request, and others won't
 * reset all the interface state (notably endpoint state).  Resetting the whole
 * configuration would affect other drivers' interfaces.
 *
 * The caller must own the device lock.
 *
 * Return: Zero on success, else a negative error code.
 */
int usb_reset_configuration(struct usb_device *dev)
{
	int			i, retval;
	struct usb_host_config	*config;
	struct usb_hcd *hcd = bus_to_hcd(dev->bus);
	if (dev->state == USB_STATE_SUSPENDED)
		return -EHOSTUNREACH;
	/* caller must have locked the device and must own
         * the usb bus readlock (so driver bindings are stable);
         * calls during probe() are fine
         */
	for (i = 1; i < 16; ++i) {
		usb_disable_endpoint(dev, i, true);
		usb_disable_endpoint(dev, i + USB_DIR_IN, true);
	}
	config = dev->actconfig;
	retval = 0;
	mutex_lock(hcd->bandwidth_mutex);
	/* Disable LPM, and re-enable it once the configuration is reset, so
         * that the xHCI driver can recalculate the U1/U2 timeouts.
         */
	if (usb_disable_lpm(dev)) {
		dev_err(&dev->dev, "%s Failed to disable LPM\n.", __func__);
		mutex_unlock(hcd->bandwidth_mutex);
		return -ENOMEM;
	}
	/* Make sure we have enough bandwidth for each alternate setting 0 */
	for (i = 0; i < config->desc.bNumInterfaces; i++) {
		struct usb_interface *intf = config->interface[i];
		struct usb_host_interface *alt;
		alt = usb_altnum_to_altsetting(intf, 0);
		if (!alt)
			alt = &intf->altsetting[0];
		if (alt != intf->cur_altsetting)
			retval = usb_hcd_alloc_bandwidth(dev, NULL,
					intf->cur_altsetting, alt);
		if (retval < 0)
			break;
	}
	/* If not, reinstate the old alternate settings */
	if (retval < 0) {
reset_old_alts:
		for (i--; i >= 0; i--) {
			struct usb_interface *intf = config->interface[i];
			struct usb_host_interface *alt;
			alt = usb_altnum_to_altsetting(intf, 0);
			if (!alt)
				alt = &intf->altsetting[0];
			if (alt != intf->cur_altsetting)
				usb_hcd_alloc_bandwidth(dev, NULL,
						alt, intf->cur_altsetting);
		}
		usb_enable_lpm(dev);
		mutex_unlock(hcd->bandwidth_mutex);
		return retval;
	}
	retval = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
			USB_REQ_SET_CONFIGURATION, 0,
			config->desc.bConfigurationValue, 0,
			NULL, 0, USB_CTRL_SET_TIMEOUT);
	if (retval < 0)
		goto reset_old_alts;
	mutex_unlock(hcd->bandwidth_mutex);
	/* re-init hc/hcd interface/endpoint state */
	for (i = 0; i < config->desc.bNumInterfaces; i++) {
		struct usb_interface *intf = config->interface[i];
		struct usb_host_interface *alt;
		alt = usb_altnum_to_altsetting(intf, 0);
		/* No altsetting 0?  We'll assume the first altsetting.
                 * We could use a GetInterface call, but if a device is
                 * so non-compliant that it doesn't have altsetting 0
                 * then I wouldn't trust its reply anyway.
                 */
		if (!alt)
			alt = &intf->altsetting[0];
		if (alt != intf->cur_altsetting) {
			remove_intf_ep_devs(intf);
			usb_remove_sysfs_intf_files(intf);
		}
		intf->cur_altsetting = alt;
		usb_enable_interface(dev, intf, true);
		if (device_is_registered(&intf->dev)) {
			usb_create_sysfs_intf_files(intf);
			create_intf_ep_devs(intf);
		}
	}
	/* Now that the interfaces are installed, re-enable LPM. */
	usb_unlocked_enable_lpm(dev);
	return 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| sarah sharp | sarah sharp | 263 | 52.71% | 2 | 13.33% | 
| alan stern | alan stern | 222 | 44.49% | 10 | 66.67% | 
| david brownell | david brownell | 8 | 1.60% | 1 | 6.67% | 
| patrick mochel | patrick mochel | 4 | 0.80% | 1 | 6.67% | 
| roel kluin | roel kluin | 2 | 0.40% | 1 | 6.67% | 
 | Total | 499 | 100.00% | 15 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_reset_configuration);
static void usb_release_interface(struct device *dev)
{
	struct usb_interface *intf = to_usb_interface(dev);
	struct usb_interface_cache *intfc =
			altsetting_to_usb_interface_cache(intf->altsetting);
	kref_put(&intfc->ref, usb_release_interface_cache);
	usb_put_dev(interface_to_usbdev(intf));
	kfree(intf);
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 42 | 75.00% | 4 | 44.44% | 
| david brownell | david brownell | 10 | 17.86% | 2 | 22.22% | 
| greg kroah-hartman | greg kroah-hartman | 3 | 5.36% | 2 | 22.22% | 
| kay sievers | kay sievers | 1 | 1.79% | 1 | 11.11% | 
 | Total | 56 | 100.00% | 9 | 100.00% | 
/*
 * usb_deauthorize_interface - deauthorize an USB interface
 *
 * @intf: USB interface structure
 */
void usb_deauthorize_interface(struct usb_interface *intf)
{
	struct device *dev = &intf->dev;
	device_lock(dev->parent);
	if (intf->authorized) {
		device_lock(dev);
		intf->authorized = 0;
		device_unlock(dev);
		usb_forced_unbind_intf(intf);
	}
	device_unlock(dev->parent);
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| stefan koch | stefan koch | 63 | 100.00% | 1 | 100.00% | 
 | Total | 63 | 100.00% | 1 | 100.00% | 
/*
 * usb_authorize_interface - authorize an USB interface
 *
 * @intf: USB interface structure
 */
void usb_authorize_interface(struct usb_interface *intf)
{
	struct device *dev = &intf->dev;
	if (!intf->authorized) {
		device_lock(dev);
		intf->authorized = 1; /* authorize interface */
		device_unlock(dev);
	}
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| stefan koch | stefan koch | 46 | 100.00% | 1 | 100.00% | 
 | Total | 46 | 100.00% | 1 | 100.00% | 
static int usb_if_uevent(struct device *dev, struct kobj_uevent_env *env)
{
	struct usb_device *usb_dev;
	struct usb_interface *intf;
	struct usb_host_interface *alt;
	intf = to_usb_interface(dev);
	usb_dev = interface_to_usbdev(intf);
	alt = intf->cur_altsetting;
	if (add_uevent_var(env, "INTERFACE=%d/%d/%d",
		   alt->desc.bInterfaceClass,
		   alt->desc.bInterfaceSubClass,
		   alt->desc.bInterfaceProtocol))
		return -ENOMEM;
	if (add_uevent_var(env,
		   "MODALIAS=usb:"
		   "v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02Xic%02Xisc%02Xip%02Xin%02X",
		   le16_to_cpu(usb_dev->descriptor.idVendor),
		   le16_to_cpu(usb_dev->descriptor.idProduct),
		   le16_to_cpu(usb_dev->descriptor.bcdDevice),
		   usb_dev->descriptor.bDeviceClass,
		   usb_dev->descriptor.bDeviceSubClass,
		   usb_dev->descriptor.bDeviceProtocol,
		   alt->desc.bInterfaceClass,
		   alt->desc.bInterfaceSubClass,
		   alt->desc.bInterfaceProtocol,
		   alt->desc.bInterfaceNumber))
		return -ENOMEM;
	return 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| kay sievers | kay sievers | 160 | 95.24% | 2 | 50.00% | 
| bjorn mork | bjorn mork | 7 | 4.17% | 1 | 25.00% | 
| greg kroah-hartman | greg kroah-hartman | 1 | 0.60% | 1 | 25.00% | 
 | Total | 168 | 100.00% | 4 | 100.00% | 
struct device_type usb_if_device_type = {
	.name =		"usb_interface",
	.release =	usb_release_interface,
	.uevent =	usb_if_uevent,
};
static struct usb_interface_assoc_descriptor *find_iad(struct usb_device *dev,
						struct usb_host_config *config,
						u8 inum)
{
	struct usb_interface_assoc_descriptor *retval = NULL;
	struct usb_interface_assoc_descriptor *intf_assoc;
	int first_intf;
	int last_intf;
	int i;
	for (i = 0; (i < USB_MAXIADS && config->intf_assoc[i]); i++) {
		intf_assoc = config->intf_assoc[i];
		if (intf_assoc->bInterfaceCount == 0)
			continue;
		first_intf = intf_assoc->bFirstInterface;
		last_intf = first_intf + (intf_assoc->bInterfaceCount - 1);
		if (inum >= first_intf && inum <= last_intf) {
			if (!retval)
				retval = intf_assoc;
			else
				dev_err(&dev->dev, "Interface #%d referenced"
					" by multiple IADs\n", inum);
		}
	}
	return retval;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| craig w. nadler | craig w. nadler | 140 | 100.00% | 1 | 100.00% | 
 | Total | 140 | 100.00% | 1 | 100.00% | 
/*
 * Internal function to queue a device reset
 * See usb_queue_reset_device() for more details
 */
static void __usb_queue_reset_device(struct work_struct *ws)
{
	int rc;
	struct usb_interface *iface =
		container_of(ws, struct usb_interface, reset_ws);
	struct usb_device *udev = interface_to_usbdev(iface);
	rc = usb_lock_device_for_reset(udev, iface);
	if (rc >= 0) {
		usb_reset_device(udev);
		usb_unlock_device(udev);
	}
	usb_put_intf(iface);	/* Undo _get_ in usb_queue_reset_device() */
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| inaky perez-gonzalez | inaky perez-gonzalez | 65 | 90.28% | 1 | 33.33% | 
| alan stern | alan stern | 6 | 8.33% | 1 | 33.33% | 
| felipe balbi | felipe balbi | 1 | 1.39% | 1 | 33.33% | 
 | Total | 72 | 100.00% | 3 | 100.00% | 
/*
 * usb_set_configuration - Makes a particular device setting be current
 * @dev: the device whose configuration is being updated
 * @configuration: the configuration being chosen.
 * Context: !in_interrupt(), caller owns the device lock
 *
 * This is used to enable non-default device modes.  Not all devices
 * use this kind of configurability; many devices only have one
 * configuration.
 *
 * @configuration is the value of the configuration to be installed.
 * According to the USB spec (e.g. section 9.1.1.5), configuration values
 * must be non-zero; a value of zero indicates that the device in
 * unconfigured.  However some devices erroneously use 0 as one of their
 * configuration values.  To help manage such devices, this routine will
 * accept @configuration = -1 as indicating the device should be put in
 * an unconfigured state.
 *
 * USB device configurations may affect Linux interoperability,
 * power consumption and the functionality available.  For example,
 * the default configuration is limited to using 100mA of bus power,
 * so that when certain device functionality requires more power,
 * and the device is bus powered, that functionality should be in some
 * non-default device configuration.  Other device modes may also be
 * reflected as configuration options, such as whether two ISDN
 * channels are available independently; and choosing between open
 * standard device protocols (like CDC) or proprietary ones.
 *
 * Note that a non-authorized device (dev->authorized == 0) will only
 * be put in unconfigured mode.
 *
 * Note that USB has an additional level of device configurability,
 * associated with interfaces.  That configurability is accessed using
 * usb_set_interface().
 *
 * This call is synchronous. The calling context must be able to sleep,
 * must own the device lock, and must not hold the driver model's USB
 * bus mutex; usb interface driver probe() methods cannot use this routine.
 *
 * Returns zero on success, or else the status code returned by the
 * underlying call that failed.  On successful completion, each interface
 * in the original device configuration has been destroyed, and each one
 * in the new configuration has been probed by all relevant usb device
 * drivers currently known to the kernel.
 */
int usb_set_configuration(struct usb_device *dev, int configuration)
{
	int i, ret;
	struct usb_host_config *cp = NULL;
	struct usb_interface **new_interfaces = NULL;
	struct usb_hcd *hcd = bus_to_hcd(dev->bus);
	int n, nintf;
	if (dev->authorized == 0 || configuration == -1)
		configuration = 0;
	else {
		for (i = 0; i < dev->descriptor.bNumConfigurations; i++) {
			if (dev->config[i].desc.bConfigurationValue ==
					configuration) {
				cp = &dev->config[i];
				break;
			}
		}
	}
	if ((!cp && configuration != 0))
		return -EINVAL;
	/* The USB spec says configuration 0 means unconfigured.
         * But if a device includes a configuration numbered 0,
         * we will accept it as a correctly configured state.
         * Use -1 if you really want to unconfigure the device.
         */
	if (cp && configuration == 0)
		dev_warn(&dev->dev, "config 0 descriptor??\n");
	/* Allocate memory for new interfaces before doing anything else,
         * so that if we run out then nothing will have changed. */
	n = nintf = 0;
	if (cp) {
		nintf = cp->desc.bNumInterfaces;
		new_interfaces = kmalloc(nintf * sizeof(*new_interfaces),
				GFP_NOIO);
		if (!new_interfaces) {
			dev_err(&dev->dev, "Out of memory\n");
			return -ENOMEM;
		}
		for (; n < nintf; ++n) {
			new_interfaces[n] = kzalloc(
					sizeof(struct usb_interface),
					GFP_NOIO);
			if (!new_interfaces[n]) {
				dev_err(&dev->dev, "Out of memory\n");
				ret = -ENOMEM;
free_interfaces:
				while (--n >= 0)
					kfree(new_interfaces[n]);
				kfree(new_interfaces);
				return ret;
			}
		}
		i = dev->bus_mA - usb_get_max_power(dev, cp);
		if (i < 0)
			dev_warn(&dev->dev, "new config #%d exceeds power "
					"limit by %dmA\n",
					configuration, -i);
	}
	/* Wake up the device so we can send it the Set-Config request */
	ret = usb_autoresume_device(dev);
	if (ret)
		goto free_interfaces;
	/* if it's already configured, clear out old state first.
         * getting rid of old interfaces means unbinding their drivers.
         */
	if (dev->state != USB_STATE_ADDRESS)
		usb_disable_device(dev, 1);	/* Skip ep0 */
	/* Get rid of pending async Set-Config requests for this device */
	cancel_async_set_config(dev);
	/* Make sure we have bandwidth (and available HCD resources) for this
         * configuration.  Remove endpoints from the schedule if we're dropping
         * this configuration to set configuration 0.  After this point, the
         * host controller will not allow submissions to dropped endpoints.  If
         * this call fails, the device state is unchanged.
         */
	mutex_lock(hcd->bandwidth_mutex);
	/* Disable LPM, and re-enable it once the new configuration is
         * installed, so that the xHCI driver can recalculate the U1/U2
         * timeouts.
         */
	if (dev->actconfig && usb_disable_lpm(dev)) {
		dev_err(&dev->dev, "%s Failed to disable LPM\n.", __func__);
		mutex_unlock(hcd->bandwidth_mutex);
		ret = -ENOMEM;
		goto free_interfaces;
	}
	ret = usb_hcd_alloc_bandwidth(dev, cp, NULL, NULL);
	if (ret < 0) {
		if (dev->actconfig)
			usb_enable_lpm(dev);
		mutex_unlock(hcd->bandwidth_mutex);
		usb_autosuspend_device(dev);
		goto free_interfaces;
	}
	/*
         * Initialize the new interface structures and the
         * hc/hcd/usbcore interface/endpoint state.
         */
	for (i = 0; i < nintf; ++i) {
		struct usb_interface_cache *intfc;
		struct usb_interface *intf;
		struct usb_host_interface *alt;
		cp->interface[i] = intf = new_interfaces[i];
		intfc = cp->intf_cache[i];
		intf->altsetting = intfc->altsetting;
		intf->num_altsetting = intfc->num_altsetting;
		intf->authorized = !!HCD_INTF_AUTHORIZED(hcd);
		kref_get(&intfc->ref);
		alt = usb_altnum_to_altsetting(intf, 0);
		/* No altsetting 0?  We'll assume the first altsetting.
                 * We could use a GetInterface call, but if a device is
                 * so non-compliant that it doesn't have altsetting 0
                 * then I wouldn't trust its reply anyway.
                 */
		if (!alt)
			alt = &intf->altsetting[0];
		intf->intf_assoc =
			find_iad(dev, cp, alt->desc.bInterfaceNumber);
		intf->cur_altsetting = alt;
		usb_enable_interface(dev, intf, true);
		intf->dev.parent = &dev->dev;
		intf->dev.driver = NULL;
		intf->dev.bus = &usb_bus_type;
		intf->dev.type = &usb_if_device_type;
		intf->dev.groups = usb_interface_groups;
		intf->dev.dma_mask = dev->dev.dma_mask;
		INIT_WORK(&intf->reset_ws, __usb_queue_reset_device);
		intf->minor = -1;
		device_initialize(&intf->dev);
		pm_runtime_no_callbacks(&intf->dev);
		dev_set_name(&intf->dev, "%d-%s:%d.%d",
			dev->bus->busnum, dev->devpath,
			configuration, alt->desc.bInterfaceNumber);
		usb_get_dev(dev);
	}
	kfree(new_interfaces);
	ret = usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
			      USB_REQ_SET_CONFIGURATION, 0, configuration, 0,
			      NULL, 0, USB_CTRL_SET_TIMEOUT);
	if (ret < 0 && cp) {
		/*
                 * All the old state is gone, so what else can we do?
                 * The device is probably useless now anyway.
                 */
		usb_hcd_alloc_bandwidth(dev, NULL, NULL, NULL);
		for (i = 0; i < nintf; ++i) {
			usb_disable_interface(dev, cp->interface[i], true);
			put_device(&cp->interface[i]->dev);
			cp->interface[i] = NULL;
		}
		cp = NULL;
	}
	dev->actconfig = cp;
	mutex_unlock(hcd->bandwidth_mutex);
	if (!cp) {
		usb_set_device_state(dev, USB_STATE_ADDRESS);
		/* Leave LPM disabled while the device is unconfigured. */
		usb_autosuspend_device(dev);
		return ret;
	}
	usb_set_device_state(dev, USB_STATE_CONFIGURED);
	if (cp->string == NULL &&
			!(dev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
		cp->string = usb_cache_string(dev, cp->desc.iConfiguration);
	/* Now that the interfaces are installed, re-enable LPM. */
	usb_unlocked_enable_lpm(dev);
	/* Enable LTM if it was turned off by usb_disable_device. */
	usb_enable_ltm(dev);
	/* Now that all the interfaces are set up, register them
         * to trigger binding of drivers to interfaces.  probe()
         * routines may install different altsettings and may
         * claim() any interfaces not yet bound.  Many class drivers
         * need that: CDC, audio, video, etc.
         */
	for (i = 0; i < nintf; ++i) {
		struct usb_interface *intf = cp->interface[i];
		dev_dbg(&dev->dev,
			"adding %s (config #%d, interface %d)\n",
			dev_name(&intf->dev), configuration,
			intf->cur_altsetting->desc.bInterfaceNumber);
		device_enable_async_suspend(&intf->dev);
		ret = device_add(&intf->dev);
		if (ret != 0) {
			dev_err(&dev->dev, "device_add(%s) --> %d\n",
				dev_name(&intf->dev), ret);
			continue;
		}
		create_intf_ep_devs(intf);
	}
	usb_autosuspend_device(dev);
	return 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 659 | 63.55% | 18 | 38.30% | 
| sarah sharp | sarah sharp | 98 | 9.45% | 5 | 10.64% | 
| david brownell | david brownell | 74 | 7.14% | 5 | 10.64% | 
| patrick mochel | patrick mochel | 56 | 5.40% | 1 | 2.13% | 
| thadeu lima de souza cascardo | thadeu lima de souza cascardo | 28 | 2.70% | 1 | 2.13% | 
| greg kroah-hartman | greg kroah-hartman | 22 | 2.12% | 1 | 2.13% | 
| daniel mack | daniel mack | 17 | 1.64% | 1 | 2.13% | 
| kay sievers | kay sievers | 17 | 1.64% | 3 | 6.38% | 
| inaky perez-gonzalez | inaky perez-gonzalez | 16 | 1.54% | 2 | 4.26% | 
| stefan koch | stefan koch | 11 | 1.06% | 1 | 2.13% | 
| lei ming | lei ming | 8 | 0.77% | 1 | 2.13% | 
| rafael j. wysocki | rafael j. wysocki | 8 | 0.77% | 1 | 2.13% | 
| sachin kamat | sachin kamat | 6 | 0.58% | 1 | 2.13% | 
| sebastian andrzej siewior | sebastian andrzej siewior | 5 | 0.48% | 1 | 2.13% | 
| jochen karrer | jochen karrer | 4 | 0.39% | 1 | 2.13% | 
| dmitry torokhov | dmitry torokhov | 3 | 0.29% | 1 | 2.13% | 
| oliver neukum | oliver neukum | 2 | 0.19% | 1 | 2.13% | 
| joe perches | joe perches | 2 | 0.19% | 1 | 2.13% | 
| horst schirmeier | horst schirmeier | 1 | 0.10% | 1 | 2.13% | 
 | Total | 1037 | 100.00% | 47 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_set_configuration);
static LIST_HEAD(set_config_list);
static DEFINE_SPINLOCK(set_config_lock);
struct set_config_request {
	
struct usb_device	*udev;
	
int			config;
	
struct work_struct	work;
	
struct list_head	node;
};
/* Worker routine for usb_driver_set_configuration() */
static void driver_set_config_work(struct work_struct *work)
{
	struct set_config_request *req =
		container_of(work, struct set_config_request, work);
	struct usb_device *udev = req->udev;
	usb_lock_device(udev);
	spin_lock(&set_config_lock);
	list_del(&req->node);
	spin_unlock(&set_config_lock);
	if (req->config >= -1)		/* Is req still valid? */
		usb_set_configuration(udev, req->config);
	usb_unlock_device(udev);
	usb_put_dev(udev);
	kfree(req);
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 82 | 87.23% | 2 | 66.67% | 
| david howells | david howells | 12 | 12.77% | 1 | 33.33% | 
 | Total | 94 | 100.00% | 3 | 100.00% | 
/* Cancel pending Set-Config requests for a device whose configuration
 * was just changed
 */
static void cancel_async_set_config(struct usb_device *udev)
{
	struct set_config_request *req;
	spin_lock(&set_config_lock);
	list_for_each_entry(req, &set_config_list, node) {
		if (req->udev == udev)
			req->config = -999;	/* Mark as cancelled */
	}
	spin_unlock(&set_config_lock);
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 54 | 100.00% | 1 | 100.00% | 
 | Total | 54 | 100.00% | 1 | 100.00% | 
/**
 * usb_driver_set_configuration - Provide a way for drivers to change device configurations
 * @udev: the device whose configuration is being updated
 * @config: the configuration being chosen.
 * Context: In process context, must be able to sleep
 *
 * Device interface drivers are not allowed to change device configurations.
 * This is because changing configurations will destroy the interface the
 * driver is bound to and create new ones; it would be like a floppy-disk
 * driver telling the computer to replace the floppy-disk drive with a
 * tape drive!
 *
 * Still, in certain specialized circumstances the need may arise.  This
 * routine gets around the normal restrictions by using a work thread to
 * submit the change-config request.
 *
 * Return: 0 if the request was successfully queued, error code otherwise.
 * The caller has no way to know whether the queued request will eventually
 * succeed.
 */
int usb_driver_set_configuration(struct usb_device *udev, int config)
{
	struct set_config_request *req;
	req = kmalloc(sizeof(*req), GFP_KERNEL);
	if (!req)
		return -ENOMEM;
	req->udev = udev;
	req->config = config;
	INIT_WORK(&req->work, driver_set_config_work);
	spin_lock(&set_config_lock);
	list_add(&req->node, &set_config_list);
	spin_unlock(&set_config_lock);
	usb_get_dev(udev);
	schedule_work(&req->work);
	return 0;
}
Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 101 | 100.00% | 2 | 100.00% | 
 | Total | 101 | 100.00% | 2 | 100.00% | 
EXPORT_SYMBOL_GPL(usb_driver_set_configuration);
Overall Contributors
 | Person | Tokens | Prop | Commits | CommitProp | 
| alan stern | alan stern | 3076 | 42.56% | 59 | 35.12% | 
| david brownell | david brownell | 1282 | 17.74% | 24 | 14.29% | 
| sarah sharp | sarah sharp | 693 | 9.59% | 9 | 5.36% | 
| patrick mochel | patrick mochel | 622 | 8.61% | 1 | 0.60% | 
| kay sievers | kay sievers | 203 | 2.81% | 4 | 2.38% | 
| greg kroah-hartman | greg kroah-hartman | 201 | 2.78% | 10 | 5.95% | 
| daniel mack | daniel mack | 180 | 2.49% | 3 | 1.79% | 
| duncan sands | duncan sands | 156 | 2.16% | 1 | 0.60% | 
| craig w. nadler | craig w. nadler | 140 | 1.94% | 1 | 0.60% | 
| stefan koch | stefan koch | 122 | 1.69% | 2 | 1.19% | 
| david vrabel | david vrabel | 89 | 1.23% | 2 | 1.19% | 
| inaky perez-gonzalez | inaky perez-gonzalez | 81 | 1.12% | 2 | 1.19% | 
| dale farnsworth | dale farnsworth | 51 | 0.71% | 1 | 0.60% | 
| david mosberger | david mosberger | 51 | 0.71% | 2 | 1.19% | 
| hans de goede | hans de goede | 36 | 0.50% | 1 | 0.60% | 
| thadeu lima de souza cascardo | thadeu lima de souza cascardo | 29 | 0.40% | 2 | 1.19% | 
| clemens ladisch | clemens ladisch | 26 | 0.36% | 1 | 0.60% | 
| franck bui-huu | franck bui-huu | 25 | 0.35% | 1 | 0.60% | 
| oliver neukum | oliver neukum | 22 | 0.30% | 3 | 1.79% | 
| david howells | david howells | 12 | 0.17% | 1 | 0.60% | 
| pete zaitcev | pete zaitcev | 12 | 0.17% | 1 | 0.60% | 
| yacine belkadi | yacine belkadi | 11 | 0.15% | 1 | 0.60% | 
| lei ming | lei ming | 9 | 0.12% | 2 | 1.19% | 
| brian murphy | brian murphy | 9 | 0.12% | 1 | 0.60% | 
| tony lindgren | tony lindgren | 8 | 0.11% | 1 | 0.60% | 
| rafael j. wysocki | rafael j. wysocki | 8 | 0.11% | 1 | 0.60% | 
| bjorn mork | bjorn mork | 7 | 0.10% | 1 | 0.60% | 
| harvey harrison | harvey harrison | 6 | 0.08% | 2 | 1.19% | 
| sachin kamat | sachin kamat | 6 | 0.08% | 1 | 0.60% | 
| valentina manea | valentina manea | 5 | 0.07% | 1 | 0.60% | 
| sebastian andrzej siewior | sebastian andrzej siewior | 5 | 0.07% | 1 | 0.60% | 
| mika kukkonen | mika kukkonen | 4 | 0.06% | 1 | 0.60% | 
| jochen karrer | jochen karrer | 4 | 0.06% | 1 | 0.60% | 
| nishanth aravamudan | nishanth aravamudan | 4 | 0.06% | 2 | 1.19% | 
| eric lescouet | eric lescouet | 3 | 0.04% | 1 | 0.60% | 
| dmitry torokhov | dmitry torokhov | 3 | 0.04% | 1 | 0.60% | 
| roel kluin | roel kluin | 3 | 0.04% | 2 | 1.19% | 
| tuelin izer | tuelin izer | 3 | 0.04% | 1 | 0.60% | 
| alexey dobriyan | alexey dobriyan | 2 | 0.03% | 1 | 0.60% | 
| matthew wilcox | matthew wilcox | 2 | 0.03% | 1 | 0.60% | 
| josh myer | josh myer | 2 | 0.03% | 1 | 0.60% | 
| ralf baechle | ralf baechle | 2 | 0.03% | 1 | 0.60% | 
| adrian bunk | adrian bunk | 2 | 0.03% | 2 | 1.19% | 
| joe perches | joe perches | 2 | 0.03% | 1 | 0.60% | 
| felipe balbi | felipe balbi | 1 | 0.01% | 1 | 0.60% | 
| daniel ritz | daniel ritz | 1 | 0.01% | 1 | 0.60% | 
| scot doyle | scot doyle | 1 | 0.01% | 1 | 0.60% | 
| dan carpenter | dan carpenter | 1 | 0.01% | 1 | 0.60% | 
| masanari iida | masanari iida | 1 | 0.01% | 1 | 0.60% | 
| al viro | al viro | 1 | 0.01% | 1 | 0.60% | 
| rahul bedarkar | rahul bedarkar | 1 | 0.01% | 1 | 0.60% | 
| horst schirmeier | horst schirmeier | 1 | 0.01% | 1 | 0.60% | 
| ivan kokshaysky | ivan kokshaysky | 1 | 0.01% | 1 | 0.60% | 
 | Total | 7228 | 100.00% | 168 | 100.00% | 
  
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