Merge branch 'master' into next

Conflicts:
	security/smack/smack_lsm.c

Verified and added fix by Stephen Rothwell <sfr@canb.auug.org.au>
Ok'd by Casey Schaufler <casey@schaufler-ca.com>

Signed-off-by: James Morris <jmorris@namei.org>

5 files changed, 224 insertions, 162 deletions

diff --git a/drivers/media/video/uvc/uvc_ctrl.c b/drivers/media/video/uvc/uvc_ctrl.c
index f169f773667..59f8a9ad379 100644
--- a/drivers/media/video/uvc/uvc_ctrl.c
+++ b/drivers/media/video/uvc/uvc_ctrl.c
@@ -785,7 +785,7 @@ static void __uvc_find_control(struct uvc_entity *entity, __u32 v4l2_id,
 	}
 }
 
-struct uvc_control *uvc_find_control(struct uvc_video_chain *chain,
+static struct uvc_control *uvc_find_control(struct uvc_video_chain *chain,
 	__u32 v4l2_id, struct uvc_control_mapping **mapping)
 {
 	struct uvc_control *ctrl = NULL;
@@ -944,6 +944,52 @@ done:
 	return ret;
 }
 
+/*
+ * Mapping V4L2 controls to UVC controls can be straighforward if done well.
+ * Most of the UVC controls exist in V4L2, and can be mapped directly. Some
+ * must be grouped (for instance the Red Balance, Blue Balance and Do White
+ * Balance V4L2 controls use the White Balance Component UVC control) or
+ * otherwise translated. The approach we take here is to use a translation
+ * table for the controls that can be mapped directly, and handle the others
+ * manually.
+ */
+int uvc_query_v4l2_menu(struct uvc_video_chain *chain,
+	struct v4l2_querymenu *query_menu)
+{
+	struct uvc_menu_info *menu_info;
+	struct uvc_control_mapping *mapping;
+	struct uvc_control *ctrl;
+	u32 index = query_menu->index;
+	u32 id = query_menu->id;
+	int ret;
+
+	memset(query_menu, 0, sizeof(*query_menu));
+	query_menu->id = id;
+	query_menu->index = index;
+
+	ret = mutex_lock_interruptible(&chain->ctrl_mutex);
+	if (ret < 0)
+		return -ERESTARTSYS;
+
+	ctrl = uvc_find_control(chain, query_menu->id, &mapping);
+	if (ctrl == NULL || mapping->v4l2_type != V4L2_CTRL_TYPE_MENU) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	if (query_menu->index >= mapping->menu_count) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	menu_info = &mapping->menu_info[query_menu->index];
+	strlcpy(query_menu->name, menu_info->name, sizeof query_menu->name);
+
+done:
+	mutex_unlock(&chain->ctrl_mutex);
+	return ret;
+}
+
 
 /* --------------------------------------------------------------------------
  * Control transactions
diff --git a/drivers/media/video/uvc/uvc_queue.c b/drivers/media/video/uvc/uvc_queue.c
index ed6d5449741..f14581bd707 100644
--- a/drivers/media/video/uvc/uvc_queue.c
+++ b/drivers/media/video/uvc/uvc_queue.c
@@ -90,6 +90,39 @@ void uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
 }
 
 /*
+ * Free the video buffers.
+ *
+ * This function must be called with the queue lock held.
+ */
+static int __uvc_free_buffers(struct uvc_video_queue *queue)
+{
+	unsigned int i;
+
+	for (i = 0; i < queue->count; ++i) {
+		if (queue->buffer[i].vma_use_count != 0)
+			return -EBUSY;
+	}
+
+	if (queue->count) {
+		vfree(queue->mem);
+		queue->count = 0;
+	}
+
+	return 0;
+}
+
+int uvc_free_buffers(struct uvc_video_queue *queue)
+{
+	int ret;
+
+	mutex_lock(&queue->mutex);
+	ret = __uvc_free_buffers(queue);
+	mutex_unlock(&queue->mutex);
+
+	return ret;
+}
+
+/*
  * Allocate the video buffers.
  *
  * Pages are reserved to make sure they will not be swapped, as they will be
@@ -110,7 +143,7 @@ int uvc_alloc_buffers(struct uvc_video_queue *queue, unsigned int nbuffers,
 
 	mutex_lock(&queue->mutex);
 
-	if ((ret = uvc_free_buffers(queue)) < 0)
+	if ((ret = __uvc_free_buffers(queue)) < 0)
 		goto done;
 
 	/* Bail out if no buffers should be allocated. */
@@ -152,28 +185,6 @@ done:
 }
 
 /*
- * Free the video buffers.
- *
- * This function must be called with the queue lock held.
- */
-int uvc_free_buffers(struct uvc_video_queue *queue)
-{
-	unsigned int i;
-
-	for (i = 0; i < queue->count; ++i) {
-		if (queue->buffer[i].vma_use_count != 0)
-			return -EBUSY;
-	}
-
-	if (queue->count) {
-		vfree(queue->mem);
-		queue->count = 0;
-	}
-
-	return 0;
-}
-
-/*
  * Check if buffers have been allocated.
  */
 int uvc_queue_allocated(struct uvc_video_queue *queue)
@@ -369,6 +380,82 @@ done:
 }
 
 /*
+ * VMA operations.
+ */
+static void uvc_vm_open(struct vm_area_struct *vma)
+{
+	struct uvc_buffer *buffer = vma->vm_private_data;
+	buffer->vma_use_count++;
+}
+
+static void uvc_vm_close(struct vm_area_struct *vma)
+{
+	struct uvc_buffer *buffer = vma->vm_private_data;
+	buffer->vma_use_count--;
+}
+
+static const struct vm_operations_struct uvc_vm_ops = {
+	.open		= uvc_vm_open,
+	.close		= uvc_vm_close,
+};
+
+/*
+ * Memory-map a video buffer.
+ *
+ * This function implements video buffers memory mapping and is intended to be
+ * used by the device mmap handler.
+ */
+int uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
+{
+	struct uvc_buffer *uninitialized_var(buffer);
+	struct page *page;
+	unsigned long addr, start, size;
+	unsigned int i;
+	int ret = 0;
+
+	start = vma->vm_start;
+	size = vma->vm_end - vma->vm_start;
+
+	mutex_lock(&queue->mutex);
+
+	for (i = 0; i < queue->count; ++i) {
+		buffer = &queue->buffer[i];
+		if ((buffer->buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff)
+			break;
+	}
+
+	if (i == queue->count || size != queue->buf_size) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	/*
+	 * VM_IO marks the area as being an mmaped region for I/O to a
+	 * device. It also prevents the region from being core dumped.
+	 */
+	vma->vm_flags |= VM_IO;
+
+	addr = (unsigned long)queue->mem + buffer->buf.m.offset;
+	while (size > 0) {
+		page = vmalloc_to_page((void *)addr);
+		if ((ret = vm_insert_page(vma, start, page)) < 0)
+			goto done;
+
+		start += PAGE_SIZE;
+		addr += PAGE_SIZE;
+		size -= PAGE_SIZE;
+	}
+
+	vma->vm_ops = &uvc_vm_ops;
+	vma->vm_private_data = buffer;
+	uvc_vm_open(vma);
+
+done:
+	mutex_unlock(&queue->mutex);
+	return ret;
+}
+
+/*
  * Poll the video queue.
  *
  * This function implements video queue polling and is intended to be used by
diff --git a/drivers/media/video/uvc/uvc_v4l2.c b/drivers/media/video/uvc/uvc_v4l2.c
index 6d15de9b520..9005a8d9d5f 100644
--- a/drivers/media/video/uvc/uvc_v4l2.c
+++ b/drivers/media/video/uvc/uvc_v4l2.c
@@ -101,40 +101,6 @@ done:
  */
 
 /*
- * Mapping V4L2 controls to UVC controls can be straighforward if done well.
- * Most of the UVC controls exist in V4L2, and can be mapped directly. Some
- * must be grouped (for instance the Red Balance, Blue Balance and Do White
- * Balance V4L2 controls use the White Balance Component UVC control) or
- * otherwise translated. The approach we take here is to use a translation
- * table for the controls that can be mapped directly, and handle the others
- * manually.
- */
-static int uvc_v4l2_query_menu(struct uvc_video_chain *chain,
-	struct v4l2_querymenu *query_menu)
-{
-	struct uvc_menu_info *menu_info;
-	struct uvc_control_mapping *mapping;
-	struct uvc_control *ctrl;
-	u32 index = query_menu->index;
-	u32 id = query_menu->id;
-
-	ctrl = uvc_find_control(chain, query_menu->id, &mapping);
-	if (ctrl == NULL || mapping->v4l2_type != V4L2_CTRL_TYPE_MENU)
-		return -EINVAL;
-
-	if (query_menu->index >= mapping->menu_count)
-		return -EINVAL;
-
-	memset(query_menu, 0, sizeof(*query_menu));
-	query_menu->id = id;
-	query_menu->index = index;
-
-	menu_info = &mapping->menu_info[query_menu->index];
-	strlcpy(query_menu->name, menu_info->name, sizeof query_menu->name);
-	return 0;
-}
-
-/*
  * Find the frame interval closest to the requested frame interval for the
  * given frame format and size. This should be done by the device as part of
  * the Video Probe and Commit negotiation, but some hardware don't implement
@@ -260,12 +226,14 @@ static int uvc_v4l2_try_format(struct uvc_streaming *stream,
 	 * developers test their webcams with the Linux driver as well as with
 	 * the Windows driver).
 	 */
+	mutex_lock(&stream->mutex);
 	if (stream->dev->quirks & UVC_QUIRK_PROBE_EXTRAFIELDS)
 		probe->dwMaxVideoFrameSize =
 			stream->ctrl.dwMaxVideoFrameSize;
 
 	/* Probe the device. */
 	ret = uvc_probe_video(stream, probe);
+	mutex_unlock(&stream->mutex);
 	if (ret < 0)
 		goto done;
 
@@ -289,14 +257,21 @@ done:
 static int uvc_v4l2_get_format(struct uvc_streaming *stream,
 	struct v4l2_format *fmt)
 {
-	struct uvc_format *format = stream->cur_format;
-	struct uvc_frame *frame = stream->cur_frame;
+	struct uvc_format *format;
+	struct uvc_frame *frame;
+	int ret = 0;
 
 	if (fmt->type != stream->type)
 		return -EINVAL;
 
-	if (format == NULL || frame == NULL)
-		return -EINVAL;
+	mutex_lock(&stream->mutex);
+	format = stream->cur_format;
+	frame = stream->cur_frame;
+
+	if (format == NULL || frame == NULL) {
+		ret = -EINVAL;
+		goto done;
+	}
 
 	fmt->fmt.pix.pixelformat = format->fcc;
 	fmt->fmt.pix.width = frame->wWidth;
@@ -307,7 +282,9 @@ static int uvc_v4l2_get_format(struct uvc_streaming *stream,
 	fmt->fmt.pix.colorspace = format->colorspace;
 	fmt->fmt.pix.priv = 0;
 
-	return 0;
+done:
+	mutex_unlock(&stream->mutex);
+	return ret;
 }
 
 static int uvc_v4l2_set_format(struct uvc_streaming *stream,
@@ -321,18 +298,24 @@ static int uvc_v4l2_set_format(struct uvc_streaming *stream,
 	if (fmt->type != stream->type)
 		return -EINVAL;
 
-	if (uvc_queue_allocated(&stream->queue))
-		return -EBUSY;
-
 	ret = uvc_v4l2_try_format(stream, fmt, &probe, &format, &frame);
 	if (ret < 0)
 		return ret;
 
+	mutex_lock(&stream->mutex);
+
+	if (uvc_queue_allocated(&stream->queue)) {
+		ret = -EBUSY;
+		goto done;
+	}
+
 	memcpy(&stream->ctrl, &probe, sizeof probe);
 	stream->cur_format = format;
 	stream->cur_frame = frame;
 
-	return 0;
+done:
+	mutex_unlock(&stream->mutex);
+	return ret;
 }
 
 static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream,
@@ -343,7 +326,10 @@ static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream,
 	if (parm->type != stream->type)
 		return -EINVAL;
 
+	mutex_lock(&stream->mutex);
 	numerator = stream->ctrl.dwFrameInterval;
+	mutex_unlock(&stream->mutex);
+
 	denominator = 10000000;
 	uvc_simplify_fraction(&numerator, &denominator, 8, 333);
 
@@ -370,7 +356,6 @@ static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream,
 static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
 		struct v4l2_streamparm *parm)
 {
-	struct uvc_frame *frame = stream->cur_frame;
 	struct uvc_streaming_control probe;
 	struct v4l2_fract timeperframe;
 	uint32_t interval;
@@ -379,28 +364,36 @@ static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
 	if (parm->type != stream->type)
 		return -EINVAL;
 
-	if (uvc_queue_streaming(&stream->queue))
-		return -EBUSY;
-
 	if (parm->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
 		timeperframe = parm->parm.capture.timeperframe;
 	else
 		timeperframe = parm->parm.output.timeperframe;
 
-	memcpy(&probe, &stream->ctrl, sizeof probe);
 	interval = uvc_fraction_to_interval(timeperframe.numerator,
 		timeperframe.denominator);
-
 	uvc_trace(UVC_TRACE_FORMAT, "Setting frame interval to %u/%u (%u).\n",
 		timeperframe.numerator, timeperframe.denominator, interval);
-	probe.dwFrameInterval = uvc_try_frame_interval(frame, interval);
+
+	mutex_lock(&stream->mutex);
+
+	if (uvc_queue_streaming(&stream->queue)) {
+		mutex_unlock(&stream->mutex);
+		return -EBUSY;
+	}
+
+	memcpy(&probe, &stream->ctrl, sizeof probe);
+	probe.dwFrameInterval =
+		uvc_try_frame_interval(stream->cur_frame, interval);
 
 	/* Probe the device with the new settings. */
 	ret = uvc_probe_video(stream, &probe);
-	if (ret < 0)
+	if (ret < 0) {
+		mutex_unlock(&stream->mutex);
 		return ret;
+	}
 
 	memcpy(&stream->ctrl, &probe, sizeof probe);
+	mutex_unlock(&stream->mutex);
 
 	/* Return the actual frame period. */
 	timeperframe.numerator = probe.dwFrameInterval;
@@ -528,11 +521,9 @@ static int uvc_v4l2_release(struct file *file)
 	if (uvc_has_privileges(handle)) {
 		uvc_video_enable(stream, 0);
 
-		mutex_lock(&stream->queue.mutex);
 		if (uvc_free_buffers(&stream->queue) < 0)
 			uvc_printk(KERN_ERR, "uvc_v4l2_release: Unable to "
 					"free buffers.\n");
-		mutex_unlock(&stream->queue.mutex);
 	}
 
 	/* Release the file handle. */
@@ -624,7 +615,7 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 	}
 
 	case VIDIOC_QUERYMENU:
-		return uvc_v4l2_query_menu(chain, arg);
+		return uvc_query_v4l2_menu(chain, arg);
 
 	case VIDIOC_G_EXT_CTRLS:
 	{
@@ -905,15 +896,17 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 	case VIDIOC_CROPCAP:
 	{
 		struct v4l2_cropcap *ccap = arg;
-		struct uvc_frame *frame = stream->cur_frame;
 
 		if (ccap->type != stream->type)
 			return -EINVAL;
 
 		ccap->bounds.left = 0;
 		ccap->bounds.top = 0;
-		ccap->bounds.width = frame->wWidth;
-		ccap->bounds.height = frame->wHeight;
+
+		mutex_lock(&stream->mutex);
+		ccap->bounds.width = stream->cur_frame->wWidth;
+		ccap->bounds.height = stream->cur_frame->wHeight;
+		mutex_unlock(&stream->mutex);
 
 		ccap->defrect = ccap->bounds;
 
@@ -930,8 +923,6 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 	case VIDIOC_REQBUFS:
 	{
 		struct v4l2_requestbuffers *rb = arg;
-		unsigned int bufsize =
-			stream->ctrl.dwMaxVideoFrameSize;
 
 		if (rb->type != stream->type ||
 		    rb->memory != V4L2_MEMORY_MMAP)
@@ -940,7 +931,10 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 		if ((ret = uvc_acquire_privileges(handle)) < 0)
 			return ret;
 
-		ret = uvc_alloc_buffers(&stream->queue, rb->count, bufsize);
+		mutex_lock(&stream->mutex);
+		ret = uvc_alloc_buffers(&stream->queue, rb->count,
+					stream->ctrl.dwMaxVideoFrameSize);
+		mutex_unlock(&stream->mutex);
 		if (ret < 0)
 			return ret;
 
@@ -988,7 +982,9 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 		if (!uvc_has_privileges(handle))
 			return -EBUSY;
 
+		mutex_lock(&stream->mutex);
 		ret = uvc_video_enable(stream, 1);
+		mutex_unlock(&stream->mutex);
 		if (ret < 0)
 			return ret;
 		break;
@@ -1039,11 +1035,8 @@ static long uvc_v4l2_do_ioctl(struct file *file, unsigned int cmd, void *arg)
 		return uvc_xu_ctrl_query(chain, arg, 1);
 
 	default:
-		if ((ret = v4l_compat_translate_ioctl(file, cmd, arg,
-			uvc_v4l2_do_ioctl)) == -ENOIOCTLCMD)
-			uvc_trace(UVC_TRACE_IOCTL, "Unknown ioctl 0x%08x\n",
-				  cmd);
-		return ret;
+		uvc_trace(UVC_TRACE_IOCTL, "Unknown ioctl 0x%08x\n", cmd);
+		return -EINVAL;
 	}
 
 	return ret;
@@ -1068,79 +1061,14 @@ static ssize_t uvc_v4l2_read(struct file *file, char __user *data,
 	return -EINVAL;
 }
 
-/*
- * VMA operations.
- */
-static void uvc_vm_open(struct vm_area_struct *vma)
-{
-	struct uvc_buffer *buffer = vma->vm_private_data;
-	buffer->vma_use_count++;
-}
-
-static void uvc_vm_close(struct vm_area_struct *vma)
-{
-	struct uvc_buffer *buffer = vma->vm_private_data;
-	buffer->vma_use_count--;
-}
-
-static const struct vm_operations_struct uvc_vm_ops = {
-	.open		= uvc_vm_open,
-	.close		= uvc_vm_close,
-};
-
 static int uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
 {
 	struct uvc_fh *handle = file->private_data;
 	struct uvc_streaming *stream = handle->stream;
-	struct uvc_video_queue *queue = &stream->queue;
-	struct uvc_buffer *uninitialized_var(buffer);
-	struct page *page;
-	unsigned long addr, start, size;
-	unsigned int i;
-	int ret = 0;
 
 	uvc_trace(UVC_TRACE_CALLS, "uvc_v4l2_mmap\n");
 
-	start = vma->vm_start;
-	size = vma->vm_end - vma->vm_start;
-
-	mutex_lock(&queue->mutex);
-
-	for (i = 0; i < queue->count; ++i) {
-		buffer = &queue->buffer[i];
-		if ((buffer->buf.m.offset >> PAGE_SHIFT) == vma->vm_pgoff)
-			break;
-	}
-
-	if (i == queue->count || size != queue->buf_size) {
-		ret = -EINVAL;
-		goto done;
-	}
-
-	/*
-	 * VM_IO marks the area as being an mmaped region for I/O to a
-	 * device. It also prevents the region from being core dumped.
-	 */
-	vma->vm_flags |= VM_IO;
-
-	addr = (unsigned long)queue->mem + buffer->buf.m.offset;
-	while (size > 0) {
-		page = vmalloc_to_page((void *)addr);
-		if ((ret = vm_insert_page(vma, start, page)) < 0)
-			goto done;
-
-		start += PAGE_SIZE;
-		addr += PAGE_SIZE;
-		size -= PAGE_SIZE;
-	}
-
-	vma->vm_ops = &uvc_vm_ops;
-	vma->vm_private_data = buffer;
-	uvc_vm_open(vma);
-
-done:
-	mutex_unlock(&queue->mutex);
-	return ret;
+	return uvc_queue_mmap(&stream->queue, vma);
 }
 
 static unsigned int uvc_v4l2_poll(struct file *file, poll_table *wait)
@@ -1157,7 +1085,7 @@ const struct v4l2_file_operations uvc_fops = {
 	.owner		= THIS_MODULE,
 	.open		= uvc_v4l2_open,
 	.release	= uvc_v4l2_release,
-	.ioctl		= uvc_v4l2_ioctl,
+	.unlocked_ioctl	= uvc_v4l2_ioctl,
 	.read		= uvc_v4l2_read,
 	.mmap		= uvc_v4l2_mmap,
 	.poll		= uvc_v4l2_poll,
diff --git a/drivers/media/video/uvc/uvc_video.c b/drivers/media/video/uvc/uvc_video.c
index 5555f010283..5673d673504 100644
--- a/drivers/media/video/uvc/uvc_video.c
+++ b/drivers/media/video/uvc/uvc_video.c
@@ -293,8 +293,6 @@ int uvc_probe_video(struct uvc_streaming *stream,
 	unsigned int i;
 	int ret;
 
-	mutex_lock(&stream->mutex);
-
 	/* Perform probing. The device should adjust the requested values
 	 * according to its capabilities. However, some devices, namely the
 	 * first generation UVC Logitech webcams, don't implement the Video
@@ -346,7 +344,6 @@ int uvc_probe_video(struct uvc_streaming *stream,
 	}
 
 done:
-	mutex_unlock(&stream->mutex);
 	return ret;
 }
 
diff --git a/drivers/media/video/uvc/uvcvideo.h b/drivers/media/video/uvc/uvcvideo.h
index d97cf6d6a4f..45f01e7e13d 100644
--- a/drivers/media/video/uvc/uvcvideo.h
+++ b/drivers/media/video/uvc/uvcvideo.h
@@ -436,7 +436,9 @@ struct uvc_streaming {
 	struct uvc_streaming_control ctrl;
 	struct uvc_format *cur_format;
 	struct uvc_frame *cur_frame;
-
+	/* Protect access to ctrl, cur_format, cur_frame and hardware video
+	 * probe control.
+	 */
 	struct mutex mutex;
 
 	unsigned int frozen : 1;
@@ -574,6 +576,8 @@ extern int uvc_queue_enable(struct uvc_video_queue *queue, int enable);
 extern void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect);
 extern struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
 		struct uvc_buffer *buf);
+extern int uvc_queue_mmap(struct uvc_video_queue *queue,
+		struct vm_area_struct *vma);
 extern unsigned int uvc_queue_poll(struct uvc_video_queue *queue,
 		struct file *file, poll_table *wait);
 extern int uvc_queue_allocated(struct uvc_video_queue *queue);
@@ -606,10 +610,10 @@ extern int uvc_status_suspend(struct uvc_device *dev);
 extern int uvc_status_resume(struct uvc_device *dev);
 
 /* Controls */
-extern struct uvc_control *uvc_find_control(struct uvc_video_chain *chain,
-		__u32 v4l2_id, struct uvc_control_mapping **mapping);
 extern int uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
 		struct v4l2_queryctrl *v4l2_ctrl);
+extern int uvc_query_v4l2_menu(struct uvc_video_chain *chain,
+		struct v4l2_querymenu *query_menu);
 
 extern int uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
 		const struct uvc_control_mapping *mapping);