Adding upstream version 6.6.15.upstream/6.6.15

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

13 files changed, 12108 insertions, 0 deletions

diff --git a/drivers/media/usb/uvc/Kconfig b/drivers/media/usb/uvc/Kconfig
new file mode 100644
index 000000000..579532272
--- /dev/null
+++ b/drivers/media/usb/uvc/Kconfig
@@ -0,0 +1,22 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config USB_VIDEO_CLASS
+	tristate "USB Video Class (UVC)"
+	depends on VIDEO_DEV
+	select VIDEOBUF2_VMALLOC
+	select UVC_COMMON
+	help
+	  Support for the USB Video Class (UVC).  Currently only video
+	  input devices, such as webcams, are supported.
+
+	  For more information see: <http://linux-uvc.berlios.de/>
+
+config USB_VIDEO_CLASS_INPUT_EVDEV
+	bool "UVC input events device support"
+	default y
+	depends on USB_VIDEO_CLASS
+	depends on USB_VIDEO_CLASS=INPUT || INPUT=y
+	help
+	  This option makes USB Video Class devices register an input device
+	  to report button events.
+
+	  If you are in doubt, say Y.
diff --git a/drivers/media/usb/uvc/Makefile b/drivers/media/usb/uvc/Makefile
new file mode 100644
index 000000000..4f9eee4f8
--- /dev/null
+++ b/drivers/media/usb/uvc/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0
+uvcvideo-objs  := uvc_driver.o uvc_queue.o uvc_v4l2.o uvc_video.o uvc_ctrl.o \
+		  uvc_status.o uvc_isight.o uvc_debugfs.o uvc_metadata.o
+ifeq ($(CONFIG_MEDIA_CONTROLLER),y)
+uvcvideo-objs  += uvc_entity.o
+endif
+obj-$(CONFIG_USB_VIDEO_CLASS) += uvcvideo.o
diff --git a/drivers/media/usb/uvc/uvc_ctrl.c b/drivers/media/usb/uvc/uvc_ctrl.c
new file mode 100644
index 000000000..e59a463c2
--- /dev/null
+++ b/drivers/media/usb/uvc/uvc_ctrl.c
@@ -0,0 +1,2786 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *      uvc_ctrl.c  --  USB Video Class driver - Controls
+ *
+ *      Copyright (C) 2005-2010
+ *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ */
+
+#include <asm/barrier.h>
+#include <linux/bitops.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/usb.h>
+#include <linux/usb/uvc.h>
+#include <linux/videodev2.h>
+#include <linux/vmalloc.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+#include <linux/atomic.h>
+#include <media/v4l2-ctrls.h>
+
+#include "uvcvideo.h"
+
+#define UVC_CTRL_DATA_CURRENT	0
+#define UVC_CTRL_DATA_BACKUP	1
+#define UVC_CTRL_DATA_MIN	2
+#define UVC_CTRL_DATA_MAX	3
+#define UVC_CTRL_DATA_RES	4
+#define UVC_CTRL_DATA_DEF	5
+#define UVC_CTRL_DATA_LAST	6
+
+/* ------------------------------------------------------------------------
+ * Controls
+ */
+
+static const struct uvc_control_info uvc_ctrls[] = {
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_BRIGHTNESS_CONTROL,
+		.index		= 0,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_CONTRAST_CONTROL,
+		.index		= 1,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_HUE_CONTROL,
+		.index		= 2,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_SATURATION_CONTROL,
+		.index		= 3,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_SHARPNESS_CONTROL,
+		.index		= 4,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_GAMMA_CONTROL,
+		.index		= 5,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_WHITE_BALANCE_TEMPERATURE_CONTROL,
+		.index		= 6,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_WHITE_BALANCE_COMPONENT_CONTROL,
+		.index		= 7,
+		.size		= 4,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_BACKLIGHT_COMPENSATION_CONTROL,
+		.index		= 8,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_GAIN_CONTROL,
+		.index		= 9,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_POWER_LINE_FREQUENCY_CONTROL,
+		.index		= 10,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
+				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_HUE_AUTO_CONTROL,
+		.index		= 11,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
+				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_WHITE_BALANCE_TEMPERATURE_AUTO_CONTROL,
+		.index		= 12,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
+				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_WHITE_BALANCE_COMPONENT_AUTO_CONTROL,
+		.index		= 13,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
+				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_DIGITAL_MULTIPLIER_CONTROL,
+		.index		= 14,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_DIGITAL_MULTIPLIER_LIMIT_CONTROL,
+		.index		= 15,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_ANALOG_VIDEO_STANDARD_CONTROL,
+		.index		= 16,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_GET_CUR,
+	},
+	{
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_ANALOG_LOCK_STATUS_CONTROL,
+		.index		= 17,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_GET_CUR,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_SCANNING_MODE_CONTROL,
+		.index		= 0,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_AE_MODE_CONTROL,
+		.index		= 1,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
+				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_GET_RES
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_AE_PRIORITY_CONTROL,
+		.index		= 2,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
+				| UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_EXPOSURE_TIME_ABSOLUTE_CONTROL,
+		.index		= 3,
+		.size		= 4,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_EXPOSURE_TIME_RELATIVE_CONTROL,
+		.index		= 4,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_FOCUS_ABSOLUTE_CONTROL,
+		.index		= 5,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_FOCUS_RELATIVE_CONTROL,
+		.index		= 6,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_MIN
+				| UVC_CTRL_FLAG_GET_MAX | UVC_CTRL_FLAG_GET_RES
+				| UVC_CTRL_FLAG_GET_DEF
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_IRIS_ABSOLUTE_CONTROL,
+		.index		= 7,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_IRIS_RELATIVE_CONTROL,
+		.index		= 8,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_ZOOM_ABSOLUTE_CONTROL,
+		.index		= 9,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_ZOOM_RELATIVE_CONTROL,
+		.index		= 10,
+		.size		= 3,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_MIN
+				| UVC_CTRL_FLAG_GET_MAX | UVC_CTRL_FLAG_GET_RES
+				| UVC_CTRL_FLAG_GET_DEF
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_PANTILT_ABSOLUTE_CONTROL,
+		.index		= 11,
+		.size		= 8,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_PANTILT_RELATIVE_CONTROL,
+		.index		= 12,
+		.size		= 4,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_ROLL_ABSOLUTE_CONTROL,
+		.index		= 13,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR
+				| UVC_CTRL_FLAG_GET_RANGE
+				| UVC_CTRL_FLAG_RESTORE
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_ROLL_RELATIVE_CONTROL,
+		.index		= 14,
+		.size		= 2,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_MIN
+				| UVC_CTRL_FLAG_GET_MAX | UVC_CTRL_FLAG_GET_RES
+				| UVC_CTRL_FLAG_GET_DEF
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_FOCUS_AUTO_CONTROL,
+		.index		= 17,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
+				| UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_RESTORE,
+	},
+	{
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_PRIVACY_CONTROL,
+		.index		= 18,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_SET_CUR | UVC_CTRL_FLAG_GET_CUR
+				| UVC_CTRL_FLAG_RESTORE
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+	{
+		.entity		= UVC_GUID_EXT_GPIO_CONTROLLER,
+		.selector	= UVC_CT_PRIVACY_CONTROL,
+		.index		= 0,
+		.size		= 1,
+		.flags		= UVC_CTRL_FLAG_GET_CUR
+				| UVC_CTRL_FLAG_AUTO_UPDATE,
+	},
+};
+
+static const u32 uvc_control_classes[] = {
+	V4L2_CID_CAMERA_CLASS,
+	V4L2_CID_USER_CLASS,
+};
+
+static const int exposure_auto_mapping[] = { 2, 1, 4, 8 };
+
+/*
+ * This function translates the V4L2 menu index @idx, as exposed to userspace as
+ * the V4L2 control value, to the corresponding UVC control value used by the
+ * device. The custom menu_mapping in the control @mapping is used when
+ * available, otherwise the function assumes that the V4L2 and UVC values are
+ * identical.
+ *
+ * For controls of type UVC_CTRL_DATA_TYPE_BITMASK, the UVC control value is
+ * expressed as a bitmask and is thus guaranteed to have a single bit set.
+ *
+ * The function returns -EINVAL if the V4L2 menu index @idx isn't valid for the
+ * control, which includes all controls whose type isn't UVC_CTRL_DATA_TYPE_ENUM
+ * or UVC_CTRL_DATA_TYPE_BITMASK.
+ */
+static int uvc_mapping_get_menu_value(const struct uvc_control_mapping *mapping,
+				      u32 idx)
+{
+	if (!test_bit(idx, &mapping->menu_mask))
+		return -EINVAL;
+
+	if (mapping->menu_mapping)
+		return mapping->menu_mapping[idx];
+
+	return idx;
+}
+
+static const char *
+uvc_mapping_get_menu_name(const struct uvc_control_mapping *mapping, u32 idx)
+{
+	if (!test_bit(idx, &mapping->menu_mask))
+		return NULL;
+
+	if (mapping->menu_names)
+		return mapping->menu_names[idx];
+
+	return v4l2_ctrl_get_menu(mapping->id)[idx];
+}
+
+static s32 uvc_ctrl_get_zoom(struct uvc_control_mapping *mapping,
+	u8 query, const u8 *data)
+{
+	s8 zoom = (s8)data[0];
+
+	switch (query) {
+	case UVC_GET_CUR:
+		return (zoom == 0) ? 0 : (zoom > 0 ? data[2] : -data[2]);
+
+	case UVC_GET_MIN:
+	case UVC_GET_MAX:
+	case UVC_GET_RES:
+	case UVC_GET_DEF:
+	default:
+		return data[2];
+	}
+}
+
+static void uvc_ctrl_set_zoom(struct uvc_control_mapping *mapping,
+	s32 value, u8 *data)
+{
+	data[0] = value == 0 ? 0 : (value > 0) ? 1 : 0xff;
+	data[2] = min((int)abs(value), 0xff);
+}
+
+static s32 uvc_ctrl_get_rel_speed(struct uvc_control_mapping *mapping,
+	u8 query, const u8 *data)
+{
+	unsigned int first = mapping->offset / 8;
+	s8 rel = (s8)data[first];
+
+	switch (query) {
+	case UVC_GET_CUR:
+		return (rel == 0) ? 0 : (rel > 0 ? data[first+1]
+						 : -data[first+1]);
+	case UVC_GET_MIN:
+		return -data[first+1];
+	case UVC_GET_MAX:
+	case UVC_GET_RES:
+	case UVC_GET_DEF:
+	default:
+		return data[first+1];
+	}
+}
+
+static void uvc_ctrl_set_rel_speed(struct uvc_control_mapping *mapping,
+	s32 value, u8 *data)
+{
+	unsigned int first = mapping->offset / 8;
+
+	data[first] = value == 0 ? 0 : (value > 0) ? 1 : 0xff;
+	data[first+1] = min_t(int, abs(value), 0xff);
+}
+
+static const struct uvc_control_mapping uvc_ctrl_mappings[] = {
+	{
+		.id		= V4L2_CID_BRIGHTNESS,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_BRIGHTNESS_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
+	},
+	{
+		.id		= V4L2_CID_CONTRAST,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_CONTRAST_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
+	},
+	{
+		.id		= V4L2_CID_HUE,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_HUE_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
+		.master_id	= V4L2_CID_HUE_AUTO,
+		.master_manual	= 0,
+	},
+	{
+		.id		= V4L2_CID_SATURATION,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_SATURATION_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
+	},
+	{
+		.id		= V4L2_CID_SHARPNESS,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_SHARPNESS_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
+	},
+	{
+		.id		= V4L2_CID_GAMMA,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_GAMMA_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
+	},
+	{
+		.id		= V4L2_CID_BACKLIGHT_COMPENSATION,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_BACKLIGHT_COMPENSATION_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
+	},
+	{
+		.id		= V4L2_CID_GAIN,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_GAIN_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
+	},
+	{
+		.id		= V4L2_CID_HUE_AUTO,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_HUE_AUTO_CONTROL,
+		.size		= 1,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
+		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
+		.slave_ids	= { V4L2_CID_HUE, },
+	},
+	{
+		.id		= V4L2_CID_EXPOSURE_AUTO,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_AE_MODE_CONTROL,
+		.size		= 4,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_MENU,
+		.data_type	= UVC_CTRL_DATA_TYPE_BITMASK,
+		.menu_mapping	= exposure_auto_mapping,
+		.menu_mask	= GENMASK(V4L2_EXPOSURE_APERTURE_PRIORITY,
+					  V4L2_EXPOSURE_AUTO),
+		.slave_ids	= { V4L2_CID_EXPOSURE_ABSOLUTE, },
+	},
+	{
+		.id		= V4L2_CID_EXPOSURE_AUTO_PRIORITY,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_AE_PRIORITY_CONTROL,
+		.size		= 1,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
+		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
+	},
+	{
+		.id		= V4L2_CID_EXPOSURE_ABSOLUTE,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_EXPOSURE_TIME_ABSOLUTE_CONTROL,
+		.size		= 32,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
+		.master_id	= V4L2_CID_EXPOSURE_AUTO,
+		.master_manual	= V4L2_EXPOSURE_MANUAL,
+	},
+	{
+		.id		= V4L2_CID_AUTO_WHITE_BALANCE,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_WHITE_BALANCE_TEMPERATURE_AUTO_CONTROL,
+		.size		= 1,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
+		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
+		.slave_ids	= { V4L2_CID_WHITE_BALANCE_TEMPERATURE, },
+	},
+	{
+		.id		= V4L2_CID_WHITE_BALANCE_TEMPERATURE,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_WHITE_BALANCE_TEMPERATURE_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
+		.master_id	= V4L2_CID_AUTO_WHITE_BALANCE,
+		.master_manual	= 0,
+	},
+	{
+		.id		= V4L2_CID_AUTO_WHITE_BALANCE,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_WHITE_BALANCE_COMPONENT_AUTO_CONTROL,
+		.size		= 1,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
+		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
+		.slave_ids	= { V4L2_CID_BLUE_BALANCE,
+				    V4L2_CID_RED_BALANCE },
+	},
+	{
+		.id		= V4L2_CID_BLUE_BALANCE,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_WHITE_BALANCE_COMPONENT_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
+		.master_id	= V4L2_CID_AUTO_WHITE_BALANCE,
+		.master_manual	= 0,
+	},
+	{
+		.id		= V4L2_CID_RED_BALANCE,
+		.entity		= UVC_GUID_UVC_PROCESSING,
+		.selector	= UVC_PU_WHITE_BALANCE_COMPONENT_CONTROL,
+		.size		= 16,
+		.offset		= 16,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
+		.master_id	= V4L2_CID_AUTO_WHITE_BALANCE,
+		.master_manual	= 0,
+	},
+	{
+		.id		= V4L2_CID_FOCUS_ABSOLUTE,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_FOCUS_ABSOLUTE_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
+		.master_id	= V4L2_CID_FOCUS_AUTO,
+		.master_manual	= 0,
+	},
+	{
+		.id		= V4L2_CID_FOCUS_AUTO,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_FOCUS_AUTO_CONTROL,
+		.size		= 1,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
+		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
+		.slave_ids	= { V4L2_CID_FOCUS_ABSOLUTE, },
+	},
+	{
+		.id		= V4L2_CID_IRIS_ABSOLUTE,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_IRIS_ABSOLUTE_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
+	},
+	{
+		.id		= V4L2_CID_IRIS_RELATIVE,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_IRIS_RELATIVE_CONTROL,
+		.size		= 8,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
+	},
+	{
+		.id		= V4L2_CID_ZOOM_ABSOLUTE,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_ZOOM_ABSOLUTE_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_UNSIGNED,
+	},
+	{
+		.id		= V4L2_CID_ZOOM_CONTINUOUS,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_ZOOM_RELATIVE_CONTROL,
+		.size		= 0,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
+		.get		= uvc_ctrl_get_zoom,
+		.set		= uvc_ctrl_set_zoom,
+	},
+	{
+		.id		= V4L2_CID_PAN_ABSOLUTE,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_PANTILT_ABSOLUTE_CONTROL,
+		.size		= 32,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
+	},
+	{
+		.id		= V4L2_CID_TILT_ABSOLUTE,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_PANTILT_ABSOLUTE_CONTROL,
+		.size		= 32,
+		.offset		= 32,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
+	},
+	{
+		.id		= V4L2_CID_PAN_SPEED,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_PANTILT_RELATIVE_CONTROL,
+		.size		= 16,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
+		.get		= uvc_ctrl_get_rel_speed,
+		.set		= uvc_ctrl_set_rel_speed,
+	},
+	{
+		.id		= V4L2_CID_TILT_SPEED,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_PANTILT_RELATIVE_CONTROL,
+		.size		= 16,
+		.offset		= 16,
+		.v4l2_type	= V4L2_CTRL_TYPE_INTEGER,
+		.data_type	= UVC_CTRL_DATA_TYPE_SIGNED,
+		.get		= uvc_ctrl_get_rel_speed,
+		.set		= uvc_ctrl_set_rel_speed,
+	},
+	{
+		.id		= V4L2_CID_PRIVACY,
+		.entity		= UVC_GUID_UVC_CAMERA,
+		.selector	= UVC_CT_PRIVACY_CONTROL,
+		.size		= 1,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
+		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
+	},
+	{
+		.id		= V4L2_CID_PRIVACY,
+		.entity		= UVC_GUID_EXT_GPIO_CONTROLLER,
+		.selector	= UVC_CT_PRIVACY_CONTROL,
+		.size		= 1,
+		.offset		= 0,
+		.v4l2_type	= V4L2_CTRL_TYPE_BOOLEAN,
+		.data_type	= UVC_CTRL_DATA_TYPE_BOOLEAN,
+	},
+};
+
+const struct uvc_control_mapping uvc_ctrl_power_line_mapping_limited = {
+	.id		= V4L2_CID_POWER_LINE_FREQUENCY,
+	.entity		= UVC_GUID_UVC_PROCESSING,
+	.selector	= UVC_PU_POWER_LINE_FREQUENCY_CONTROL,
+	.size		= 2,
+	.offset		= 0,
+	.v4l2_type	= V4L2_CTRL_TYPE_MENU,
+	.data_type	= UVC_CTRL_DATA_TYPE_ENUM,
+	.menu_mask	= GENMASK(V4L2_CID_POWER_LINE_FREQUENCY_60HZ,
+				  V4L2_CID_POWER_LINE_FREQUENCY_50HZ),
+};
+
+const struct uvc_control_mapping uvc_ctrl_power_line_mapping_uvc11 = {
+	.id		= V4L2_CID_POWER_LINE_FREQUENCY,
+	.entity		= UVC_GUID_UVC_PROCESSING,
+	.selector	= UVC_PU_POWER_LINE_FREQUENCY_CONTROL,
+	.size		= 2,
+	.offset		= 0,
+	.v4l2_type	= V4L2_CTRL_TYPE_MENU,
+	.data_type	= UVC_CTRL_DATA_TYPE_ENUM,
+	.menu_mask	= GENMASK(V4L2_CID_POWER_LINE_FREQUENCY_60HZ,
+				  V4L2_CID_POWER_LINE_FREQUENCY_DISABLED),
+};
+
+static const struct uvc_control_mapping *uvc_ctrl_mappings_uvc11[] = {
+	&uvc_ctrl_power_line_mapping_uvc11,
+	NULL, /* Sentinel */
+};
+
+static const struct uvc_control_mapping uvc_ctrl_power_line_mapping_uvc15 = {
+	.id		= V4L2_CID_POWER_LINE_FREQUENCY,
+	.entity		= UVC_GUID_UVC_PROCESSING,
+	.selector	= UVC_PU_POWER_LINE_FREQUENCY_CONTROL,
+	.size		= 2,
+	.offset		= 0,
+	.v4l2_type	= V4L2_CTRL_TYPE_MENU,
+	.data_type	= UVC_CTRL_DATA_TYPE_ENUM,
+	.menu_mask	= GENMASK(V4L2_CID_POWER_LINE_FREQUENCY_AUTO,
+				  V4L2_CID_POWER_LINE_FREQUENCY_DISABLED),
+};
+
+static const struct uvc_control_mapping *uvc_ctrl_mappings_uvc15[] = {
+	&uvc_ctrl_power_line_mapping_uvc15,
+	NULL, /* Sentinel */
+};
+
+/* ------------------------------------------------------------------------
+ * Utility functions
+ */
+
+static inline u8 *uvc_ctrl_data(struct uvc_control *ctrl, int id)
+{
+	return ctrl->uvc_data + id * ctrl->info.size;
+}
+
+static inline int uvc_test_bit(const u8 *data, int bit)
+{
+	return (data[bit >> 3] >> (bit & 7)) & 1;
+}
+
+static inline void uvc_clear_bit(u8 *data, int bit)
+{
+	data[bit >> 3] &= ~(1 << (bit & 7));
+}
+
+/*
+ * Extract the bit string specified by mapping->offset and mapping->size
+ * from the little-endian data stored at 'data' and return the result as
+ * a signed 32bit integer. Sign extension will be performed if the mapping
+ * references a signed data type.
+ */
+static s32 uvc_get_le_value(struct uvc_control_mapping *mapping,
+	u8 query, const u8 *data)
+{
+	int bits = mapping->size;
+	int offset = mapping->offset;
+	s32 value = 0;
+	u8 mask;
+
+	data += offset / 8;
+	offset &= 7;
+	mask = ((1LL << bits) - 1) << offset;
+
+	while (1) {
+		u8 byte = *data & mask;
+		value |= offset > 0 ? (byte >> offset) : (byte << (-offset));
+		bits -= 8 - (offset > 0 ? offset : 0);
+		if (bits <= 0)
+			break;
+
+		offset -= 8;
+		mask = (1 << bits) - 1;
+		data++;
+	}
+
+	/* Sign-extend the value if needed. */
+	if (mapping->data_type == UVC_CTRL_DATA_TYPE_SIGNED)
+		value |= -(value & (1 << (mapping->size - 1)));
+
+	return value;
+}
+
+/*
+ * Set the bit string specified by mapping->offset and mapping->size
+ * in the little-endian data stored at 'data' to the value 'value'.
+ */
+static void uvc_set_le_value(struct uvc_control_mapping *mapping,
+	s32 value, u8 *data)
+{
+	int bits = mapping->size;
+	int offset = mapping->offset;
+	u8 mask;
+
+	/*
+	 * According to the v4l2 spec, writing any value to a button control
+	 * should result in the action belonging to the button control being
+	 * triggered. UVC devices however want to see a 1 written -> override
+	 * value.
+	 */
+	if (mapping->v4l2_type == V4L2_CTRL_TYPE_BUTTON)
+		value = -1;
+
+	data += offset / 8;
+	offset &= 7;
+
+	for (; bits > 0; data++) {
+		mask = ((1LL << bits) - 1) << offset;
+		*data = (*data & ~mask) | ((value << offset) & mask);
+		value >>= offset ? offset : 8;
+		bits -= 8 - offset;
+		offset = 0;
+	}
+}
+
+/* ------------------------------------------------------------------------
+ * Terminal and unit management
+ */
+
+static int uvc_entity_match_guid(const struct uvc_entity *entity,
+				 const u8 guid[16])
+{
+	return memcmp(entity->guid, guid, sizeof(entity->guid)) == 0;
+}
+
+/* ------------------------------------------------------------------------
+ * UVC Controls
+ */
+
+static void __uvc_find_control(struct uvc_entity *entity, u32 v4l2_id,
+	struct uvc_control_mapping **mapping, struct uvc_control **control,
+	int next)
+{
+	struct uvc_control *ctrl;
+	struct uvc_control_mapping *map;
+	unsigned int i;
+
+	if (entity == NULL)
+		return;
+
+	for (i = 0; i < entity->ncontrols; ++i) {
+		ctrl = &entity->controls[i];
+		if (!ctrl->initialized)
+			continue;
+
+		list_for_each_entry(map, &ctrl->info.mappings, list) {
+			if ((map->id == v4l2_id) && !next) {
+				*control = ctrl;
+				*mapping = map;
+				return;
+			}
+
+			if ((*mapping == NULL || (*mapping)->id > map->id) &&
+			    (map->id > v4l2_id) && next) {
+				*control = ctrl;
+				*mapping = map;
+			}
+		}
+	}
+}
+
+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;
+	struct uvc_entity *entity;
+	int next = v4l2_id & V4L2_CTRL_FLAG_NEXT_CTRL;
+
+	*mapping = NULL;
+
+	/* Mask the query flags. */
+	v4l2_id &= V4L2_CTRL_ID_MASK;
+
+	/* Find the control. */
+	list_for_each_entry(entity, &chain->entities, chain) {
+		__uvc_find_control(entity, v4l2_id, mapping, &ctrl, next);
+		if (ctrl && !next)
+			return ctrl;
+	}
+
+	if (ctrl == NULL && !next)
+		uvc_dbg(chain->dev, CONTROL, "Control 0x%08x not found\n",
+			v4l2_id);
+
+	return ctrl;
+}
+
+static int uvc_ctrl_populate_cache(struct uvc_video_chain *chain,
+	struct uvc_control *ctrl)
+{
+	int ret;
+
+	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_DEF) {
+		ret = uvc_query_ctrl(chain->dev, UVC_GET_DEF, ctrl->entity->id,
+				     chain->dev->intfnum, ctrl->info.selector,
+				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_DEF),
+				     ctrl->info.size);
+		if (ret < 0)
+			return ret;
+	}
+
+	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN) {
+		ret = uvc_query_ctrl(chain->dev, UVC_GET_MIN, ctrl->entity->id,
+				     chain->dev->intfnum, ctrl->info.selector,
+				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MIN),
+				     ctrl->info.size);
+		if (ret < 0)
+			return ret;
+	}
+	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX) {
+		ret = uvc_query_ctrl(chain->dev, UVC_GET_MAX, ctrl->entity->id,
+				     chain->dev->intfnum, ctrl->info.selector,
+				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MAX),
+				     ctrl->info.size);
+		if (ret < 0)
+			return ret;
+	}
+	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_RES) {
+		ret = uvc_query_ctrl(chain->dev, UVC_GET_RES, ctrl->entity->id,
+				     chain->dev->intfnum, ctrl->info.selector,
+				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES),
+				     ctrl->info.size);
+		if (ret < 0) {
+			if (UVC_ENTITY_TYPE(ctrl->entity) !=
+			    UVC_VC_EXTENSION_UNIT)
+				return ret;
+
+			/*
+			 * GET_RES is mandatory for XU controls, but some
+			 * cameras still choke on it. Ignore errors and set the
+			 * resolution value to zero.
+			 */
+			uvc_warn_once(chain->dev, UVC_WARN_XU_GET_RES,
+				      "UVC non compliance - GET_RES failed on "
+				      "an XU control. Enabling workaround.\n");
+			memset(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES), 0,
+			       ctrl->info.size);
+		}
+	}
+
+	ctrl->cached = 1;
+	return 0;
+}
+
+static s32 __uvc_ctrl_get_value(struct uvc_control_mapping *mapping,
+				const u8 *data)
+{
+	s32 value = mapping->get(mapping, UVC_GET_CUR, data);
+
+	if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
+		unsigned int i;
+
+		for (i = 0; BIT(i) <= mapping->menu_mask; ++i) {
+			u32 menu_value;
+
+			if (!test_bit(i, &mapping->menu_mask))
+				continue;
+
+			menu_value = uvc_mapping_get_menu_value(mapping, i);
+
+			if (menu_value == value) {
+				value = i;
+				break;
+			}
+		}
+	}
+
+	return value;
+}
+
+static int __uvc_ctrl_load_cur(struct uvc_video_chain *chain,
+			       struct uvc_control *ctrl)
+{
+	u8 *data;
+	int ret;
+
+	if (ctrl->loaded)
+		return 0;
+
+	data = uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT);
+
+	if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) == 0) {
+		memset(data, 0, ctrl->info.size);
+		ctrl->loaded = 1;
+
+		return 0;
+	}
+
+	if (ctrl->entity->get_cur)
+		ret = ctrl->entity->get_cur(chain->dev, ctrl->entity,
+					    ctrl->info.selector, data,
+					    ctrl->info.size);
+	else
+		ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR,
+				     ctrl->entity->id, chain->dev->intfnum,
+				     ctrl->info.selector, data,
+				     ctrl->info.size);
+
+	if (ret < 0)
+		return ret;
+
+	ctrl->loaded = 1;
+
+	return ret;
+}
+
+static int __uvc_ctrl_get(struct uvc_video_chain *chain,
+			  struct uvc_control *ctrl,
+			  struct uvc_control_mapping *mapping,
+			  s32 *value)
+{
+	int ret;
+
+	if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) == 0)
+		return -EACCES;
+
+	ret = __uvc_ctrl_load_cur(chain, ctrl);
+	if (ret < 0)
+		return ret;
+
+	*value = __uvc_ctrl_get_value(mapping,
+				uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
+
+	return 0;
+}
+
+static int __uvc_query_v4l2_class(struct uvc_video_chain *chain, u32 req_id,
+				  u32 found_id)
+{
+	bool find_next = req_id & V4L2_CTRL_FLAG_NEXT_CTRL;
+	unsigned int i;
+
+	req_id &= V4L2_CTRL_ID_MASK;
+
+	for (i = 0; i < ARRAY_SIZE(uvc_control_classes); i++) {
+		if (!(chain->ctrl_class_bitmap & BIT(i)))
+			continue;
+		if (!find_next) {
+			if (uvc_control_classes[i] == req_id)
+				return i;
+			continue;
+		}
+		if (uvc_control_classes[i] > req_id &&
+		    uvc_control_classes[i] < found_id)
+			return i;
+	}
+
+	return -ENODEV;
+}
+
+static int uvc_query_v4l2_class(struct uvc_video_chain *chain, u32 req_id,
+				u32 found_id, struct v4l2_queryctrl *v4l2_ctrl)
+{
+	int idx;
+
+	idx = __uvc_query_v4l2_class(chain, req_id, found_id);
+	if (idx < 0)
+		return -ENODEV;
+
+	memset(v4l2_ctrl, 0, sizeof(*v4l2_ctrl));
+	v4l2_ctrl->id = uvc_control_classes[idx];
+	strscpy(v4l2_ctrl->name, v4l2_ctrl_get_name(v4l2_ctrl->id),
+		sizeof(v4l2_ctrl->name));
+	v4l2_ctrl->type = V4L2_CTRL_TYPE_CTRL_CLASS;
+	v4l2_ctrl->flags = V4L2_CTRL_FLAG_WRITE_ONLY
+			 | V4L2_CTRL_FLAG_READ_ONLY;
+	return 0;
+}
+
+/*
+ * Check if control @v4l2_id can be accessed by the given control @ioctl
+ * (VIDIOC_G_EXT_CTRLS, VIDIOC_TRY_EXT_CTRLS or VIDIOC_S_EXT_CTRLS).
+ *
+ * For set operations on slave controls, check if the master's value is set to
+ * manual, either in the others controls set in the same ioctl call, or from
+ * the master's current value. This catches VIDIOC_S_EXT_CTRLS calls that set
+ * both the master and slave control, such as for instance setting
+ * auto_exposure=1, exposure_time_absolute=251.
+ */
+int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
+			   const struct v4l2_ext_controls *ctrls,
+			   unsigned long ioctl)
+{
+	struct uvc_control_mapping *master_map = NULL;
+	struct uvc_control *master_ctrl = NULL;
+	struct uvc_control_mapping *mapping;
+	struct uvc_control *ctrl;
+	bool read = ioctl == VIDIOC_G_EXT_CTRLS;
+	s32 val;
+	int ret;
+	int i;
+
+	if (__uvc_query_v4l2_class(chain, v4l2_id, 0) >= 0)
+		return -EACCES;
+
+	ctrl = uvc_find_control(chain, v4l2_id, &mapping);
+	if (!ctrl)
+		return -EINVAL;
+
+	if (!(ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) && read)
+		return -EACCES;
+
+	if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR) && !read)
+		return -EACCES;
+
+	if (ioctl != VIDIOC_S_EXT_CTRLS || !mapping->master_id)
+		return 0;
+
+	/*
+	 * Iterate backwards in cases where the master control is accessed
+	 * multiple times in the same ioctl. We want the last value.
+	 */
+	for (i = ctrls->count - 1; i >= 0; i--) {
+		if (ctrls->controls[i].id == mapping->master_id)
+			return ctrls->controls[i].value ==
+					mapping->master_manual ? 0 : -EACCES;
+	}
+
+	__uvc_find_control(ctrl->entity, mapping->master_id, &master_map,
+			   &master_ctrl, 0);
+
+	if (!master_ctrl || !(master_ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR))
+		return 0;
+
+	ret = __uvc_ctrl_get(chain, master_ctrl, master_map, &val);
+	if (ret >= 0 && val != mapping->master_manual)
+		return -EACCES;
+
+	return 0;
+}
+
+static const char *uvc_map_get_name(const struct uvc_control_mapping *map)
+{
+	const char *name;
+
+	if (map->name)
+		return map->name;
+
+	name = v4l2_ctrl_get_name(map->id);
+	if (name)
+		return name;
+
+	return "Unknown Control";
+}
+
+static u32 uvc_get_ctrl_bitmap(struct uvc_control *ctrl,
+			       struct uvc_control_mapping *mapping)
+{
+	/*
+	 * Some controls, like CT_AE_MODE_CONTROL, use GET_RES to represent
+	 * the number of bits supported. Those controls do not list GET_MAX
+	 * as supported.
+	 */
+	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_RES)
+		return mapping->get(mapping, UVC_GET_RES,
+				    uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES));
+
+	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX)
+		return mapping->get(mapping, UVC_GET_MAX,
+				    uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MAX));
+
+	return ~0;
+}
+
+static int __uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
+	struct uvc_control *ctrl,
+	struct uvc_control_mapping *mapping,
+	struct v4l2_queryctrl *v4l2_ctrl)
+{
+	struct uvc_control_mapping *master_map = NULL;
+	struct uvc_control *master_ctrl = NULL;
+	unsigned int i;
+
+	memset(v4l2_ctrl, 0, sizeof(*v4l2_ctrl));
+	v4l2_ctrl->id = mapping->id;
+	v4l2_ctrl->type = mapping->v4l2_type;
+	strscpy(v4l2_ctrl->name, uvc_map_get_name(mapping),
+		sizeof(v4l2_ctrl->name));
+	v4l2_ctrl->flags = 0;
+
+	if (!(ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR))
+		v4l2_ctrl->flags |= V4L2_CTRL_FLAG_WRITE_ONLY;
+	if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR))
+		v4l2_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
+
+	if (mapping->master_id)
+		__uvc_find_control(ctrl->entity, mapping->master_id,
+				   &master_map, &master_ctrl, 0);
+	if (master_ctrl && (master_ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR)) {
+		s32 val;
+		int ret = __uvc_ctrl_get(chain, master_ctrl, master_map, &val);
+		if (ret < 0)
+			return ret;
+
+		if (val != mapping->master_manual)
+				v4l2_ctrl->flags |= V4L2_CTRL_FLAG_INACTIVE;
+	}
+
+	if (!ctrl->cached) {
+		int ret = uvc_ctrl_populate_cache(chain, ctrl);
+		if (ret < 0)
+			return ret;
+	}
+
+	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_DEF) {
+		v4l2_ctrl->default_value = mapping->get(mapping, UVC_GET_DEF,
+				uvc_ctrl_data(ctrl, UVC_CTRL_DATA_DEF));
+	}
+
+	switch (mapping->v4l2_type) {
+	case V4L2_CTRL_TYPE_MENU:
+		v4l2_ctrl->minimum = ffs(mapping->menu_mask) - 1;
+		v4l2_ctrl->maximum = fls(mapping->menu_mask) - 1;
+		v4l2_ctrl->step = 1;
+
+		for (i = 0; BIT(i) <= mapping->menu_mask; ++i) {
+			u32 menu_value;
+
+			if (!test_bit(i, &mapping->menu_mask))
+				continue;
+
+			menu_value = uvc_mapping_get_menu_value(mapping, i);
+
+			if (menu_value == v4l2_ctrl->default_value) {
+				v4l2_ctrl->default_value = i;
+				break;
+			}
+		}
+
+		return 0;
+
+	case V4L2_CTRL_TYPE_BOOLEAN:
+		v4l2_ctrl->minimum = 0;
+		v4l2_ctrl->maximum = 1;
+		v4l2_ctrl->step = 1;
+		return 0;
+
+	case V4L2_CTRL_TYPE_BUTTON:
+		v4l2_ctrl->minimum = 0;
+		v4l2_ctrl->maximum = 0;
+		v4l2_ctrl->step = 0;
+		return 0;
+
+	case V4L2_CTRL_TYPE_BITMASK:
+		v4l2_ctrl->minimum = 0;
+		v4l2_ctrl->maximum = uvc_get_ctrl_bitmap(ctrl, mapping);
+		v4l2_ctrl->step = 0;
+		return 0;
+
+	default:
+		break;
+	}
+
+	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_MIN)
+		v4l2_ctrl->minimum = mapping->get(mapping, UVC_GET_MIN,
+				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MIN));
+
+	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_MAX)
+		v4l2_ctrl->maximum = mapping->get(mapping, UVC_GET_MAX,
+				     uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MAX));
+
+	if (ctrl->info.flags & UVC_CTRL_FLAG_GET_RES)
+		v4l2_ctrl->step = mapping->get(mapping, UVC_GET_RES,
+				  uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES));
+
+	return 0;
+}
+
+int uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
+	struct v4l2_queryctrl *v4l2_ctrl)
+{
+	struct uvc_control *ctrl;
+	struct uvc_control_mapping *mapping;
+	int ret;
+
+	ret = mutex_lock_interruptible(&chain->ctrl_mutex);
+	if (ret < 0)
+		return -ERESTARTSYS;
+
+	/* Check if the ctrl is a know class */
+	if (!(v4l2_ctrl->id & V4L2_CTRL_FLAG_NEXT_CTRL)) {
+		ret = uvc_query_v4l2_class(chain, v4l2_ctrl->id, 0, v4l2_ctrl);
+		if (!ret)
+			goto done;
+	}
+
+	ctrl = uvc_find_control(chain, v4l2_ctrl->id, &mapping);
+	if (ctrl == NULL) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	/*
+	 * If we're enumerating control with V4L2_CTRL_FLAG_NEXT_CTRL, check if
+	 * a class should be inserted between the previous control and the one
+	 * we have just found.
+	 */
+	if (v4l2_ctrl->id & V4L2_CTRL_FLAG_NEXT_CTRL) {
+		ret = uvc_query_v4l2_class(chain, v4l2_ctrl->id, mapping->id,
+					   v4l2_ctrl);
+		if (!ret)
+			goto done;
+	}
+
+	ret = __uvc_query_v4l2_ctrl(chain, ctrl, mapping, v4l2_ctrl);
+done:
+	mutex_unlock(&chain->ctrl_mutex);
+	return ret;
+}
+
+/*
+ * Mapping V4L2 controls to UVC controls can be straightforward 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_control_mapping *mapping;
+	struct uvc_control *ctrl;
+	u32 index = query_menu->index;
+	u32 id = query_menu->id;
+	const char *name;
+	int ret;
+
+	memset(query_menu, 0, sizeof(*query_menu));
+	query_menu->id = id;
+	query_menu->index = index;
+
+	if (index >= BITS_PER_TYPE(mapping->menu_mask))
+		return -EINVAL;
+
+	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 (!test_bit(query_menu->index, &mapping->menu_mask)) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	if (mapping->data_type == UVC_CTRL_DATA_TYPE_BITMASK) {
+		int mask;
+
+		if (!ctrl->cached) {
+			ret = uvc_ctrl_populate_cache(chain, ctrl);
+			if (ret < 0)
+				goto done;
+		}
+
+		mask = uvc_mapping_get_menu_value(mapping, query_menu->index);
+		if (mask < 0) {
+			ret = mask;
+			goto done;
+		}
+
+		if (!(uvc_get_ctrl_bitmap(ctrl, mapping) & mask)) {
+			ret = -EINVAL;
+			goto done;
+		}
+	}
+
+	name = uvc_mapping_get_menu_name(mapping, query_menu->index);
+	if (!name) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	strscpy(query_menu->name, name, sizeof(query_menu->name));
+
+done:
+	mutex_unlock(&chain->ctrl_mutex);
+	return ret;
+}
+
+/* --------------------------------------------------------------------------
+ * Ctrl event handling
+ */
+
+static void uvc_ctrl_fill_event(struct uvc_video_chain *chain,
+	struct v4l2_event *ev,
+	struct uvc_control *ctrl,
+	struct uvc_control_mapping *mapping,
+	s32 value, u32 changes)
+{
+	struct v4l2_queryctrl v4l2_ctrl;
+
+	__uvc_query_v4l2_ctrl(chain, ctrl, mapping, &v4l2_ctrl);
+
+	memset(ev, 0, sizeof(*ev));
+	ev->type = V4L2_EVENT_CTRL;
+	ev->id = v4l2_ctrl.id;
+	ev->u.ctrl.value = value;
+	ev->u.ctrl.changes = changes;
+	ev->u.ctrl.type = v4l2_ctrl.type;
+	ev->u.ctrl.flags = v4l2_ctrl.flags;
+	ev->u.ctrl.minimum = v4l2_ctrl.minimum;
+	ev->u.ctrl.maximum = v4l2_ctrl.maximum;
+	ev->u.ctrl.step = v4l2_ctrl.step;
+	ev->u.ctrl.default_value = v4l2_ctrl.default_value;
+}
+
+/*
+ * Send control change events to all subscribers for the @ctrl control. By
+ * default the subscriber that generated the event, as identified by @handle,
+ * is not notified unless it has set the V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK flag.
+ * @handle can be NULL for asynchronous events related to auto-update controls,
+ * in which case all subscribers are notified.
+ */
+static void uvc_ctrl_send_event(struct uvc_video_chain *chain,
+	struct uvc_fh *handle, struct uvc_control *ctrl,
+	struct uvc_control_mapping *mapping, s32 value, u32 changes)
+{
+	struct v4l2_fh *originator = handle ? &handle->vfh : NULL;
+	struct v4l2_subscribed_event *sev;
+	struct v4l2_event ev;
+
+	if (list_empty(&mapping->ev_subs))
+		return;
+
+	uvc_ctrl_fill_event(chain, &ev, ctrl, mapping, value, changes);
+
+	list_for_each_entry(sev, &mapping->ev_subs, node) {
+		if (sev->fh != originator ||
+		    (sev->flags & V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK) ||
+		    (changes & V4L2_EVENT_CTRL_CH_FLAGS))
+			v4l2_event_queue_fh(sev->fh, &ev);
+	}
+}
+
+/*
+ * Send control change events for the slave of the @master control identified
+ * by the V4L2 ID @slave_id. The @handle identifies the event subscriber that
+ * generated the event and may be NULL for auto-update events.
+ */
+static void uvc_ctrl_send_slave_event(struct uvc_video_chain *chain,
+	struct uvc_fh *handle, struct uvc_control *master, u32 slave_id)
+{
+	struct uvc_control_mapping *mapping = NULL;
+	struct uvc_control *ctrl = NULL;
+	u32 changes = V4L2_EVENT_CTRL_CH_FLAGS;
+	s32 val = 0;
+
+	__uvc_find_control(master->entity, slave_id, &mapping, &ctrl, 0);
+	if (ctrl == NULL)
+		return;
+
+	if (__uvc_ctrl_get(chain, ctrl, mapping, &val) == 0)
+		changes |= V4L2_EVENT_CTRL_CH_VALUE;
+
+	uvc_ctrl_send_event(chain, handle, ctrl, mapping, val, changes);
+}
+
+void uvc_ctrl_status_event(struct uvc_video_chain *chain,
+			   struct uvc_control *ctrl, const u8 *data)
+{
+	struct uvc_control_mapping *mapping;
+	struct uvc_fh *handle;
+	unsigned int i;
+
+	mutex_lock(&chain->ctrl_mutex);
+
+	handle = ctrl->handle;
+	ctrl->handle = NULL;
+
+	list_for_each_entry(mapping, &ctrl->info.mappings, list) {
+		s32 value = __uvc_ctrl_get_value(mapping, data);
+
+		/*
+		 * handle may be NULL here if the device sends auto-update
+		 * events without a prior related control set from userspace.
+		 */
+		for (i = 0; i < ARRAY_SIZE(mapping->slave_ids); ++i) {
+			if (!mapping->slave_ids[i])
+				break;
+
+			uvc_ctrl_send_slave_event(chain, handle, ctrl,
+						  mapping->slave_ids[i]);
+		}
+
+		uvc_ctrl_send_event(chain, handle, ctrl, mapping, value,
+				    V4L2_EVENT_CTRL_CH_VALUE);
+	}
+
+	mutex_unlock(&chain->ctrl_mutex);
+}
+
+static void uvc_ctrl_status_event_work(struct work_struct *work)
+{
+	struct uvc_device *dev = container_of(work, struct uvc_device,
+					      async_ctrl.work);
+	struct uvc_ctrl_work *w = &dev->async_ctrl;
+	int ret;
+
+	uvc_ctrl_status_event(w->chain, w->ctrl, w->data);
+
+	/* The barrier is needed to synchronize with uvc_status_stop(). */
+	if (smp_load_acquire(&dev->flush_status))
+		return;
+
+	/* Resubmit the URB. */
+	w->urb->interval = dev->int_ep->desc.bInterval;
+	ret = usb_submit_urb(w->urb, GFP_KERNEL);
+	if (ret < 0)
+		dev_err(&dev->udev->dev,
+			"Failed to resubmit status URB (%d).\n", ret);
+}
+
+bool uvc_ctrl_status_event_async(struct urb *urb, struct uvc_video_chain *chain,
+				 struct uvc_control *ctrl, const u8 *data)
+{
+	struct uvc_device *dev = chain->dev;
+	struct uvc_ctrl_work *w = &dev->async_ctrl;
+
+	if (list_empty(&ctrl->info.mappings)) {
+		ctrl->handle = NULL;
+		return false;
+	}
+
+	w->data = data;
+	w->urb = urb;
+	w->chain = chain;
+	w->ctrl = ctrl;
+
+	schedule_work(&w->work);
+
+	return true;
+}
+
+static bool uvc_ctrl_xctrls_has_control(const struct v4l2_ext_control *xctrls,
+					unsigned int xctrls_count, u32 id)
+{
+	unsigned int i;
+
+	for (i = 0; i < xctrls_count; ++i) {
+		if (xctrls[i].id == id)
+			return true;
+	}
+
+	return false;
+}
+
+static void uvc_ctrl_send_events(struct uvc_fh *handle,
+	const struct v4l2_ext_control *xctrls, unsigned int xctrls_count)
+{
+	struct uvc_control_mapping *mapping;
+	struct uvc_control *ctrl;
+	u32 changes = V4L2_EVENT_CTRL_CH_VALUE;
+	unsigned int i;
+	unsigned int j;
+
+	for (i = 0; i < xctrls_count; ++i) {
+		ctrl = uvc_find_control(handle->chain, xctrls[i].id, &mapping);
+
+		if (ctrl->info.flags & UVC_CTRL_FLAG_ASYNCHRONOUS)
+			/* Notification will be sent from an Interrupt event. */
+			continue;
+
+		for (j = 0; j < ARRAY_SIZE(mapping->slave_ids); ++j) {
+			u32 slave_id = mapping->slave_ids[j];
+
+			if (!slave_id)
+				break;
+
+			/*
+			 * We can skip sending an event for the slave if the
+			 * slave is being modified in the same transaction.
+			 */
+			if (uvc_ctrl_xctrls_has_control(xctrls, xctrls_count,
+							slave_id))
+				continue;
+
+			uvc_ctrl_send_slave_event(handle->chain, handle, ctrl,
+						  slave_id);
+		}
+
+		/*
+		 * If the master is being modified in the same transaction
+		 * flags may change too.
+		 */
+		if (mapping->master_id &&
+		    uvc_ctrl_xctrls_has_control(xctrls, xctrls_count,
+						mapping->master_id))
+			changes |= V4L2_EVENT_CTRL_CH_FLAGS;
+
+		uvc_ctrl_send_event(handle->chain, handle, ctrl, mapping,
+				    xctrls[i].value, changes);
+	}
+}
+
+static int uvc_ctrl_add_event(struct v4l2_subscribed_event *sev, unsigned elems)
+{
+	struct uvc_fh *handle = container_of(sev->fh, struct uvc_fh, vfh);
+	struct uvc_control_mapping *mapping;
+	struct uvc_control *ctrl;
+	int ret;
+
+	ret = mutex_lock_interruptible(&handle->chain->ctrl_mutex);
+	if (ret < 0)
+		return -ERESTARTSYS;
+
+	if (__uvc_query_v4l2_class(handle->chain, sev->id, 0) >= 0) {
+		ret = 0;
+		goto done;
+	}
+
+	ctrl = uvc_find_control(handle->chain, sev->id, &mapping);
+	if (ctrl == NULL) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	list_add_tail(&sev->node, &mapping->ev_subs);
+	if (sev->flags & V4L2_EVENT_SUB_FL_SEND_INITIAL) {
+		struct v4l2_event ev;
+		u32 changes = V4L2_EVENT_CTRL_CH_FLAGS;
+		s32 val = 0;
+
+		if (__uvc_ctrl_get(handle->chain, ctrl, mapping, &val) == 0)
+			changes |= V4L2_EVENT_CTRL_CH_VALUE;
+
+		uvc_ctrl_fill_event(handle->chain, &ev, ctrl, mapping, val,
+				    changes);
+		/*
+		 * Mark the queue as active, allowing this initial event to be
+		 * accepted.
+		 */
+		sev->elems = elems;
+		v4l2_event_queue_fh(sev->fh, &ev);
+	}
+
+done:
+	mutex_unlock(&handle->chain->ctrl_mutex);
+	return ret;
+}
+
+static void uvc_ctrl_del_event(struct v4l2_subscribed_event *sev)
+{
+	struct uvc_fh *handle = container_of(sev->fh, struct uvc_fh, vfh);
+
+	mutex_lock(&handle->chain->ctrl_mutex);
+	if (__uvc_query_v4l2_class(handle->chain, sev->id, 0) >= 0)
+		goto done;
+	list_del(&sev->node);
+done:
+	mutex_unlock(&handle->chain->ctrl_mutex);
+}
+
+const struct v4l2_subscribed_event_ops uvc_ctrl_sub_ev_ops = {
+	.add = uvc_ctrl_add_event,
+	.del = uvc_ctrl_del_event,
+	.replace = v4l2_ctrl_replace,
+	.merge = v4l2_ctrl_merge,
+};
+
+/* --------------------------------------------------------------------------
+ * Control transactions
+ *
+ * To make extended set operations as atomic as the hardware allows, controls
+ * are handled using begin/commit/rollback operations.
+ *
+ * At the beginning of a set request, uvc_ctrl_begin should be called to
+ * initialize the request. This function acquires the control lock.
+ *
+ * When setting a control, the new value is stored in the control data field
+ * at position UVC_CTRL_DATA_CURRENT. The control is then marked as dirty for
+ * later processing. If the UVC and V4L2 control sizes differ, the current
+ * value is loaded from the hardware before storing the new value in the data
+ * field.
+ *
+ * After processing all controls in the transaction, uvc_ctrl_commit or
+ * uvc_ctrl_rollback must be called to apply the pending changes to the
+ * hardware or revert them. When applying changes, all controls marked as
+ * dirty will be modified in the UVC device, and the dirty flag will be
+ * cleared. When reverting controls, the control data field
+ * UVC_CTRL_DATA_CURRENT is reverted to its previous value
+ * (UVC_CTRL_DATA_BACKUP) for all dirty controls. Both functions release the
+ * control lock.
+ */
+int uvc_ctrl_begin(struct uvc_video_chain *chain)
+{
+	return mutex_lock_interruptible(&chain->ctrl_mutex) ? -ERESTARTSYS : 0;
+}
+
+static int uvc_ctrl_commit_entity(struct uvc_device *dev,
+	struct uvc_entity *entity, int rollback, struct uvc_control **err_ctrl)
+{
+	struct uvc_control *ctrl;
+	unsigned int i;
+	int ret;
+
+	if (entity == NULL)
+		return 0;
+
+	for (i = 0; i < entity->ncontrols; ++i) {
+		ctrl = &entity->controls[i];
+		if (!ctrl->initialized)
+			continue;
+
+		/*
+		 * Reset the loaded flag for auto-update controls that were
+		 * marked as loaded in uvc_ctrl_get/uvc_ctrl_set to prevent
+		 * uvc_ctrl_get from using the cached value, and for write-only
+		 * controls to prevent uvc_ctrl_set from setting bits not
+		 * explicitly set by the user.
+		 */
+		if (ctrl->info.flags & UVC_CTRL_FLAG_AUTO_UPDATE ||
+		    !(ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR))
+			ctrl->loaded = 0;
+
+		if (!ctrl->dirty)
+			continue;
+
+		if (!rollback)
+			ret = uvc_query_ctrl(dev, UVC_SET_CUR, ctrl->entity->id,
+				dev->intfnum, ctrl->info.selector,
+				uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
+				ctrl->info.size);
+		else
+			ret = 0;
+
+		if (rollback || ret < 0)
+			memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
+			       uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP),
+			       ctrl->info.size);
+
+		ctrl->dirty = 0;
+
+		if (ret < 0) {
+			if (err_ctrl)
+				*err_ctrl = ctrl;
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static int uvc_ctrl_find_ctrl_idx(struct uvc_entity *entity,
+				  struct v4l2_ext_controls *ctrls,
+				  struct uvc_control *uvc_control)
+{
+	struct uvc_control_mapping *mapping = NULL;
+	struct uvc_control *ctrl_found = NULL;
+	unsigned int i;
+
+	if (!entity)
+		return ctrls->count;
+
+	for (i = 0; i < ctrls->count; i++) {
+		__uvc_find_control(entity, ctrls->controls[i].id, &mapping,
+				   &ctrl_found, 0);
+		if (uvc_control == ctrl_found)
+			return i;
+	}
+
+	return ctrls->count;
+}
+
+int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
+		      struct v4l2_ext_controls *ctrls)
+{
+	struct uvc_video_chain *chain = handle->chain;
+	struct uvc_control *err_ctrl;
+	struct uvc_entity *entity;
+	int ret = 0;
+
+	/* Find the control. */
+	list_for_each_entry(entity, &chain->entities, chain) {
+		ret = uvc_ctrl_commit_entity(chain->dev, entity, rollback,
+					     &err_ctrl);
+		if (ret < 0)
+			goto done;
+	}
+
+	if (!rollback)
+		uvc_ctrl_send_events(handle, ctrls->controls, ctrls->count);
+done:
+	if (ret < 0 && ctrls)
+		ctrls->error_idx = uvc_ctrl_find_ctrl_idx(entity, ctrls,
+							  err_ctrl);
+	mutex_unlock(&chain->ctrl_mutex);
+	return ret;
+}
+
+int uvc_ctrl_get(struct uvc_video_chain *chain,
+	struct v4l2_ext_control *xctrl)
+{
+	struct uvc_control *ctrl;
+	struct uvc_control_mapping *mapping;
+
+	if (__uvc_query_v4l2_class(chain, xctrl->id, 0) >= 0)
+		return -EACCES;
+
+	ctrl = uvc_find_control(chain, xctrl->id, &mapping);
+	if (ctrl == NULL)
+		return -EINVAL;
+
+	return __uvc_ctrl_get(chain, ctrl, mapping, &xctrl->value);
+}
+
+int uvc_ctrl_set(struct uvc_fh *handle,
+	struct v4l2_ext_control *xctrl)
+{
+	struct uvc_video_chain *chain = handle->chain;
+	struct uvc_control *ctrl;
+	struct uvc_control_mapping *mapping;
+	s32 value;
+	u32 step;
+	s32 min;
+	s32 max;
+	int ret;
+
+	if (__uvc_query_v4l2_class(chain, xctrl->id, 0) >= 0)
+		return -EACCES;
+
+	ctrl = uvc_find_control(chain, xctrl->id, &mapping);
+	if (ctrl == NULL)
+		return -EINVAL;
+	if (!(ctrl->info.flags & UVC_CTRL_FLAG_SET_CUR))
+		return -EACCES;
+
+	/* Clamp out of range values. */
+	switch (mapping->v4l2_type) {
+	case V4L2_CTRL_TYPE_INTEGER:
+		if (!ctrl->cached) {
+			ret = uvc_ctrl_populate_cache(chain, ctrl);
+			if (ret < 0)
+				return ret;
+		}
+
+		min = mapping->get(mapping, UVC_GET_MIN,
+				   uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MIN));
+		max = mapping->get(mapping, UVC_GET_MAX,
+				   uvc_ctrl_data(ctrl, UVC_CTRL_DATA_MAX));
+		step = mapping->get(mapping, UVC_GET_RES,
+				    uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES));
+		if (step == 0)
+			step = 1;
+
+		xctrl->value = min + DIV_ROUND_CLOSEST((u32)(xctrl->value - min),
+							step) * step;
+		if (mapping->data_type == UVC_CTRL_DATA_TYPE_SIGNED)
+			xctrl->value = clamp(xctrl->value, min, max);
+		else
+			xctrl->value = clamp_t(u32, xctrl->value, min, max);
+		value = xctrl->value;
+		break;
+
+	case V4L2_CTRL_TYPE_BITMASK:
+		if (!ctrl->cached) {
+			ret = uvc_ctrl_populate_cache(chain, ctrl);
+			if (ret < 0)
+				return ret;
+		}
+
+		xctrl->value &= uvc_get_ctrl_bitmap(ctrl, mapping);
+		value = xctrl->value;
+		break;
+
+	case V4L2_CTRL_TYPE_BOOLEAN:
+		xctrl->value = clamp(xctrl->value, 0, 1);
+		value = xctrl->value;
+		break;
+
+	case V4L2_CTRL_TYPE_MENU:
+		if (xctrl->value < (ffs(mapping->menu_mask) - 1) ||
+		    xctrl->value > (fls(mapping->menu_mask) - 1))
+			return -ERANGE;
+
+		if (!test_bit(xctrl->value, &mapping->menu_mask))
+			return -EINVAL;
+
+		value = uvc_mapping_get_menu_value(mapping, xctrl->value);
+
+		/*
+		 * Valid menu indices are reported by the GET_RES request for
+		 * UVC controls that support it.
+		 */
+		if (mapping->data_type == UVC_CTRL_DATA_TYPE_BITMASK) {
+			if (!ctrl->cached) {
+				ret = uvc_ctrl_populate_cache(chain, ctrl);
+				if (ret < 0)
+					return ret;
+			}
+
+			if (!(uvc_get_ctrl_bitmap(ctrl, mapping) & value))
+				return -EINVAL;
+		}
+
+		break;
+
+	default:
+		value = xctrl->value;
+		break;
+	}
+
+	/*
+	 * If the mapping doesn't span the whole UVC control, the current value
+	 * needs to be loaded from the device to perform the read-modify-write
+	 * operation.
+	 */
+	if ((ctrl->info.size * 8) != mapping->size) {
+		ret = __uvc_ctrl_load_cur(chain, ctrl);
+		if (ret < 0)
+			return ret;
+	}
+
+	/* Backup the current value in case we need to rollback later. */
+	if (!ctrl->dirty) {
+		memcpy(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_BACKUP),
+		       uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
+		       ctrl->info.size);
+	}
+
+	mapping->set(mapping, value,
+		uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
+
+	if (ctrl->info.flags & UVC_CTRL_FLAG_ASYNCHRONOUS)
+		ctrl->handle = handle;
+
+	ctrl->dirty = 1;
+	ctrl->modified = 1;
+	return 0;
+}
+
+/* --------------------------------------------------------------------------
+ * Dynamic controls
+ */
+
+/*
+ * Retrieve flags for a given control
+ */
+static int uvc_ctrl_get_flags(struct uvc_device *dev,
+			      const struct uvc_control *ctrl,
+			      struct uvc_control_info *info)
+{
+	u8 *data;
+	int ret;
+
+	data = kmalloc(1, GFP_KERNEL);
+	if (data == NULL)
+		return -ENOMEM;
+
+	if (ctrl->entity->get_info)
+		ret = ctrl->entity->get_info(dev, ctrl->entity,
+					     ctrl->info.selector, data);
+	else
+		ret = uvc_query_ctrl(dev, UVC_GET_INFO, ctrl->entity->id,
+				     dev->intfnum, info->selector, data, 1);
+	if (!ret)
+		info->flags |= (data[0] & UVC_CONTROL_CAP_GET ?
+				UVC_CTRL_FLAG_GET_CUR : 0)
+			    |  (data[0] & UVC_CONTROL_CAP_SET ?
+				UVC_CTRL_FLAG_SET_CUR : 0)
+			    |  (data[0] & UVC_CONTROL_CAP_AUTOUPDATE ?
+				UVC_CTRL_FLAG_AUTO_UPDATE : 0)
+			    |  (data[0] & UVC_CONTROL_CAP_ASYNCHRONOUS ?
+				UVC_CTRL_FLAG_ASYNCHRONOUS : 0);
+
+	kfree(data);
+	return ret;
+}
+
+static void uvc_ctrl_fixup_xu_info(struct uvc_device *dev,
+	const struct uvc_control *ctrl, struct uvc_control_info *info)
+{
+	struct uvc_ctrl_fixup {
+		struct usb_device_id id;
+		u8 entity;
+		u8 selector;
+		u8 flags;
+	};
+
+	static const struct uvc_ctrl_fixup fixups[] = {
+		{ { USB_DEVICE(0x046d, 0x08c2) }, 9, 1,
+			UVC_CTRL_FLAG_GET_MIN | UVC_CTRL_FLAG_GET_MAX |
+			UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_SET_CUR |
+			UVC_CTRL_FLAG_AUTO_UPDATE },
+		{ { USB_DEVICE(0x046d, 0x08cc) }, 9, 1,
+			UVC_CTRL_FLAG_GET_MIN | UVC_CTRL_FLAG_GET_MAX |
+			UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_SET_CUR |
+			UVC_CTRL_FLAG_AUTO_UPDATE },
+		{ { USB_DEVICE(0x046d, 0x0994) }, 9, 1,
+			UVC_CTRL_FLAG_GET_MIN | UVC_CTRL_FLAG_GET_MAX |
+			UVC_CTRL_FLAG_GET_DEF | UVC_CTRL_FLAG_SET_CUR |
+			UVC_CTRL_FLAG_AUTO_UPDATE },
+	};
+
+	unsigned int i;
+
+	for (i = 0; i < ARRAY_SIZE(fixups); ++i) {
+		if (!usb_match_one_id(dev->intf, &fixups[i].id))
+			continue;
+
+		if (fixups[i].entity == ctrl->entity->id &&
+		    fixups[i].selector == info->selector) {
+			info->flags = fixups[i].flags;
+			return;
+		}
+	}
+}
+
+/*
+ * Query control information (size and flags) for XU controls.
+ */
+static int uvc_ctrl_fill_xu_info(struct uvc_device *dev,
+	const struct uvc_control *ctrl, struct uvc_control_info *info)
+{
+	u8 *data;
+	int ret;
+
+	data = kmalloc(2, GFP_KERNEL);
+	if (data == NULL)
+		return -ENOMEM;
+
+	memcpy(info->entity, ctrl->entity->guid, sizeof(info->entity));
+	info->index = ctrl->index;
+	info->selector = ctrl->index + 1;
+
+	/* Query and verify the control length (GET_LEN) */
+	ret = uvc_query_ctrl(dev, UVC_GET_LEN, ctrl->entity->id, dev->intfnum,
+			     info->selector, data, 2);
+	if (ret < 0) {
+		uvc_dbg(dev, CONTROL,
+			"GET_LEN failed on control %pUl/%u (%d)\n",
+			info->entity, info->selector, ret);
+		goto done;
+	}
+
+	info->size = le16_to_cpup((__le16 *)data);
+
+	info->flags = UVC_CTRL_FLAG_GET_MIN | UVC_CTRL_FLAG_GET_MAX
+		    | UVC_CTRL_FLAG_GET_RES | UVC_CTRL_FLAG_GET_DEF;
+
+	ret = uvc_ctrl_get_flags(dev, ctrl, info);
+	if (ret < 0) {
+		uvc_dbg(dev, CONTROL,
+			"Failed to get flags for control %pUl/%u (%d)\n",
+			info->entity, info->selector, ret);
+		goto done;
+	}
+
+	uvc_ctrl_fixup_xu_info(dev, ctrl, info);
+
+	uvc_dbg(dev, CONTROL,
+		"XU control %pUl/%u queried: len %u, flags { get %u set %u auto %u }\n",
+		info->entity, info->selector, info->size,
+		(info->flags & UVC_CTRL_FLAG_GET_CUR) ? 1 : 0,
+		(info->flags & UVC_CTRL_FLAG_SET_CUR) ? 1 : 0,
+		(info->flags & UVC_CTRL_FLAG_AUTO_UPDATE) ? 1 : 0);
+
+done:
+	kfree(data);
+	return ret;
+}
+
+static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
+	const struct uvc_control_info *info);
+
+static int uvc_ctrl_init_xu_ctrl(struct uvc_device *dev,
+	struct uvc_control *ctrl)
+{
+	struct uvc_control_info info;
+	int ret;
+
+	if (ctrl->initialized)
+		return 0;
+
+	ret = uvc_ctrl_fill_xu_info(dev, ctrl, &info);
+	if (ret < 0)
+		return ret;
+
+	ret = uvc_ctrl_add_info(dev, ctrl, &info);
+	if (ret < 0)
+		uvc_dbg(dev, CONTROL,
+			"Failed to initialize control %pUl/%u on device %s entity %u\n",
+			info.entity, info.selector, dev->udev->devpath,
+			ctrl->entity->id);
+
+	return ret;
+}
+
+int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
+	struct uvc_xu_control_query *xqry)
+{
+	struct uvc_entity *entity;
+	struct uvc_control *ctrl;
+	unsigned int i;
+	bool found;
+	u32 reqflags;
+	u16 size;
+	u8 *data = NULL;
+	int ret;
+
+	/* Find the extension unit. */
+	found = false;
+	list_for_each_entry(entity, &chain->entities, chain) {
+		if (UVC_ENTITY_TYPE(entity) == UVC_VC_EXTENSION_UNIT &&
+		    entity->id == xqry->unit) {
+			found = true;
+			break;
+		}
+	}
+
+	if (!found) {
+		uvc_dbg(chain->dev, CONTROL, "Extension unit %u not found\n",
+			xqry->unit);
+		return -ENOENT;
+	}
+
+	/* Find the control and perform delayed initialization if needed. */
+	found = false;
+	for (i = 0; i < entity->ncontrols; ++i) {
+		ctrl = &entity->controls[i];
+		if (ctrl->index == xqry->selector - 1) {
+			found = true;
+			break;
+		}
+	}
+
+	if (!found) {
+		uvc_dbg(chain->dev, CONTROL, "Control %pUl/%u not found\n",
+			entity->guid, xqry->selector);
+		return -ENOENT;
+	}
+
+	if (mutex_lock_interruptible(&chain->ctrl_mutex))
+		return -ERESTARTSYS;
+
+	ret = uvc_ctrl_init_xu_ctrl(chain->dev, ctrl);
+	if (ret < 0) {
+		ret = -ENOENT;
+		goto done;
+	}
+
+	/* Validate the required buffer size and flags for the request */
+	reqflags = 0;
+	size = ctrl->info.size;
+
+	switch (xqry->query) {
+	case UVC_GET_CUR:
+		reqflags = UVC_CTRL_FLAG_GET_CUR;
+		break;
+	case UVC_GET_MIN:
+		reqflags = UVC_CTRL_FLAG_GET_MIN;
+		break;
+	case UVC_GET_MAX:
+		reqflags = UVC_CTRL_FLAG_GET_MAX;
+		break;
+	case UVC_GET_DEF:
+		reqflags = UVC_CTRL_FLAG_GET_DEF;
+		break;
+	case UVC_GET_RES:
+		reqflags = UVC_CTRL_FLAG_GET_RES;
+		break;
+	case UVC_SET_CUR:
+		reqflags = UVC_CTRL_FLAG_SET_CUR;
+		break;
+	case UVC_GET_LEN:
+		size = 2;
+		break;
+	case UVC_GET_INFO:
+		size = 1;
+		break;
+	default:
+		ret = -EINVAL;
+		goto done;
+	}
+
+	if (size != xqry->size) {
+		ret = -ENOBUFS;
+		goto done;
+	}
+
+	if (reqflags && !(ctrl->info.flags & reqflags)) {
+		ret = -EBADRQC;
+		goto done;
+	}
+
+	data = kmalloc(size, GFP_KERNEL);
+	if (data == NULL) {
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	if (xqry->query == UVC_SET_CUR &&
+	    copy_from_user(data, xqry->data, size)) {
+		ret = -EFAULT;
+		goto done;
+	}
+
+	ret = uvc_query_ctrl(chain->dev, xqry->query, xqry->unit,
+			     chain->dev->intfnum, xqry->selector, data, size);
+	if (ret < 0)
+		goto done;
+
+	if (xqry->query != UVC_SET_CUR &&
+	    copy_to_user(xqry->data, data, size))
+		ret = -EFAULT;
+done:
+	kfree(data);
+	mutex_unlock(&chain->ctrl_mutex);
+	return ret;
+}
+
+/* --------------------------------------------------------------------------
+ * Suspend/resume
+ */
+
+/*
+ * Restore control values after resume, skipping controls that haven't been
+ * changed.
+ *
+ * TODO
+ * - Don't restore modified controls that are back to their default value.
+ * - Handle restore order (Auto-Exposure Mode should be restored before
+ *   Exposure Time).
+ */
+int uvc_ctrl_restore_values(struct uvc_device *dev)
+{
+	struct uvc_control *ctrl;
+	struct uvc_entity *entity;
+	unsigned int i;
+	int ret;
+
+	/* Walk the entities list and restore controls when possible. */
+	list_for_each_entry(entity, &dev->entities, list) {
+
+		for (i = 0; i < entity->ncontrols; ++i) {
+			ctrl = &entity->controls[i];
+
+			if (!ctrl->initialized || !ctrl->modified ||
+			    (ctrl->info.flags & UVC_CTRL_FLAG_RESTORE) == 0)
+				continue;
+			dev_dbg(&dev->udev->dev,
+				"restoring control %pUl/%u/%u\n",
+				ctrl->info.entity, ctrl->info.index,
+				ctrl->info.selector);
+			ctrl->dirty = 1;
+		}
+
+		ret = uvc_ctrl_commit_entity(dev, entity, 0, NULL);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+/* --------------------------------------------------------------------------
+ * Control and mapping handling
+ */
+
+/*
+ * Add control information to a given control.
+ */
+static int uvc_ctrl_add_info(struct uvc_device *dev, struct uvc_control *ctrl,
+	const struct uvc_control_info *info)
+{
+	ctrl->info = *info;
+	INIT_LIST_HEAD(&ctrl->info.mappings);
+
+	/* Allocate an array to save control values (cur, def, max, etc.) */
+	ctrl->uvc_data = kzalloc(ctrl->info.size * UVC_CTRL_DATA_LAST + 1,
+				 GFP_KERNEL);
+	if (!ctrl->uvc_data)
+		return -ENOMEM;
+
+	ctrl->initialized = 1;
+
+	uvc_dbg(dev, CONTROL, "Added control %pUl/%u to device %s entity %u\n",
+		ctrl->info.entity, ctrl->info.selector, dev->udev->devpath,
+		ctrl->entity->id);
+
+	return 0;
+}
+
+/*
+ * Add a control mapping to a given control.
+ */
+static int __uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
+	struct uvc_control *ctrl, const struct uvc_control_mapping *mapping)
+{
+	struct uvc_control_mapping *map;
+	unsigned int size;
+	unsigned int i;
+
+	/*
+	 * Most mappings come from static kernel data, and need to be duplicated.
+	 * Mappings that come from userspace will be unnecessarily duplicated,
+	 * this could be optimized.
+	 */
+	map = kmemdup(mapping, sizeof(*mapping), GFP_KERNEL);
+	if (!map)
+		return -ENOMEM;
+
+	map->name = NULL;
+	map->menu_names = NULL;
+	map->menu_mapping = NULL;
+
+	/* For UVCIOC_CTRL_MAP custom control */
+	if (mapping->name) {
+		map->name = kstrdup(mapping->name, GFP_KERNEL);
+		if (!map->name)
+			goto err_nomem;
+	}
+
+	INIT_LIST_HEAD(&map->ev_subs);
+
+	if (mapping->menu_mapping && mapping->menu_mask) {
+		size = sizeof(mapping->menu_mapping[0])
+		       * fls(mapping->menu_mask);
+		map->menu_mapping = kmemdup(mapping->menu_mapping, size,
+					    GFP_KERNEL);
+		if (!map->menu_mapping)
+			goto err_nomem;
+	}
+	if (mapping->menu_names && mapping->menu_mask) {
+		size = sizeof(mapping->menu_names[0])
+		       * fls(mapping->menu_mask);
+		map->menu_names = kmemdup(mapping->menu_names, size,
+					  GFP_KERNEL);
+		if (!map->menu_names)
+			goto err_nomem;
+	}
+
+	if (map->get == NULL)
+		map->get = uvc_get_le_value;
+	if (map->set == NULL)
+		map->set = uvc_set_le_value;
+
+	for (i = 0; i < ARRAY_SIZE(uvc_control_classes); i++) {
+		if (V4L2_CTRL_ID2WHICH(uvc_control_classes[i]) ==
+						V4L2_CTRL_ID2WHICH(map->id)) {
+			chain->ctrl_class_bitmap |= BIT(i);
+			break;
+		}
+	}
+
+	list_add_tail(&map->list, &ctrl->info.mappings);
+	uvc_dbg(chain->dev, CONTROL, "Adding mapping '%s' to control %pUl/%u\n",
+		uvc_map_get_name(map), ctrl->info.entity,
+		ctrl->info.selector);
+
+	return 0;
+
+err_nomem:
+	kfree(map->menu_names);
+	kfree(map->menu_mapping);
+	kfree(map->name);
+	kfree(map);
+	return -ENOMEM;
+}
+
+int uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
+	const struct uvc_control_mapping *mapping)
+{
+	struct uvc_device *dev = chain->dev;
+	struct uvc_control_mapping *map;
+	struct uvc_entity *entity;
+	struct uvc_control *ctrl;
+	int found = 0;
+	int ret;
+
+	if (mapping->id & ~V4L2_CTRL_ID_MASK) {
+		uvc_dbg(dev, CONTROL,
+			"Can't add mapping '%s', control id 0x%08x is invalid\n",
+			uvc_map_get_name(mapping), mapping->id);
+		return -EINVAL;
+	}
+
+	/* Search for the matching (GUID/CS) control on the current chain */
+	list_for_each_entry(entity, &chain->entities, chain) {
+		unsigned int i;
+
+		if (UVC_ENTITY_TYPE(entity) != UVC_VC_EXTENSION_UNIT ||
+		    !uvc_entity_match_guid(entity, mapping->entity))
+			continue;
+
+		for (i = 0; i < entity->ncontrols; ++i) {
+			ctrl = &entity->controls[i];
+			if (ctrl->index == mapping->selector - 1) {
+				found = 1;
+				break;
+			}
+		}
+
+		if (found)
+			break;
+	}
+	if (!found)
+		return -ENOENT;
+
+	if (mutex_lock_interruptible(&chain->ctrl_mutex))
+		return -ERESTARTSYS;
+
+	/* Perform delayed initialization of XU controls */
+	ret = uvc_ctrl_init_xu_ctrl(dev, ctrl);
+	if (ret < 0) {
+		ret = -ENOENT;
+		goto done;
+	}
+
+	/* Validate the user-provided bit-size and offset */
+	if (mapping->size > 32 ||
+	    mapping->offset + mapping->size > ctrl->info.size * 8) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	list_for_each_entry(map, &ctrl->info.mappings, list) {
+		if (mapping->id == map->id) {
+			uvc_dbg(dev, CONTROL,
+				"Can't add mapping '%s', control id 0x%08x already exists\n",
+				uvc_map_get_name(mapping), mapping->id);
+			ret = -EEXIST;
+			goto done;
+		}
+	}
+
+	/* Prevent excess memory consumption */
+	if (atomic_inc_return(&dev->nmappings) > UVC_MAX_CONTROL_MAPPINGS) {
+		atomic_dec(&dev->nmappings);
+		uvc_dbg(dev, CONTROL,
+			"Can't add mapping '%s', maximum mappings count (%u) exceeded\n",
+			uvc_map_get_name(mapping), UVC_MAX_CONTROL_MAPPINGS);
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	ret = __uvc_ctrl_add_mapping(chain, ctrl, mapping);
+	if (ret < 0)
+		atomic_dec(&dev->nmappings);
+
+done:
+	mutex_unlock(&chain->ctrl_mutex);
+	return ret;
+}
+
+/*
+ * Prune an entity of its bogus controls using a blacklist. Bogus controls
+ * are currently the ones that crash the camera or unconditionally return an
+ * error when queried.
+ */
+static void uvc_ctrl_prune_entity(struct uvc_device *dev,
+	struct uvc_entity *entity)
+{
+	struct uvc_ctrl_blacklist {
+		struct usb_device_id id;
+		u8 index;
+	};
+
+	static const struct uvc_ctrl_blacklist processing_blacklist[] = {
+		{ { USB_DEVICE(0x13d3, 0x509b) }, 9 }, /* Gain */
+		{ { USB_DEVICE(0x1c4f, 0x3000) }, 6 }, /* WB Temperature */
+		{ { USB_DEVICE(0x5986, 0x0241) }, 2 }, /* Hue */
+	};
+	static const struct uvc_ctrl_blacklist camera_blacklist[] = {
+		{ { USB_DEVICE(0x06f8, 0x3005) }, 9 }, /* Zoom, Absolute */
+	};
+
+	const struct uvc_ctrl_blacklist *blacklist;
+	unsigned int size;
+	unsigned int count;
+	unsigned int i;
+	u8 *controls;
+
+	switch (UVC_ENTITY_TYPE(entity)) {
+	case UVC_VC_PROCESSING_UNIT:
+		blacklist = processing_blacklist;
+		count = ARRAY_SIZE(processing_blacklist);
+		controls = entity->processing.bmControls;
+		size = entity->processing.bControlSize;
+		break;
+
+	case UVC_ITT_CAMERA:
+		blacklist = camera_blacklist;
+		count = ARRAY_SIZE(camera_blacklist);
+		controls = entity->camera.bmControls;
+		size = entity->camera.bControlSize;
+		break;
+
+	default:
+		return;
+	}
+
+	for (i = 0; i < count; ++i) {
+		if (!usb_match_one_id(dev->intf, &blacklist[i].id))
+			continue;
+
+		if (blacklist[i].index >= 8 * size ||
+		    !uvc_test_bit(controls, blacklist[i].index))
+			continue;
+
+		uvc_dbg(dev, CONTROL,
+			"%u/%u control is black listed, removing it\n",
+			entity->id, blacklist[i].index);
+
+		uvc_clear_bit(controls, blacklist[i].index);
+	}
+}
+
+/*
+ * Add control information and hardcoded stock control mappings to the given
+ * device.
+ */
+static void uvc_ctrl_init_ctrl(struct uvc_video_chain *chain,
+			       struct uvc_control *ctrl)
+{
+	const struct uvc_control_mapping **mappings;
+	unsigned int i;
+
+	/*
+	 * XU controls initialization requires querying the device for control
+	 * information. As some buggy UVC devices will crash when queried
+	 * repeatedly in a tight loop, delay XU controls initialization until
+	 * first use.
+	 */
+	if (UVC_ENTITY_TYPE(ctrl->entity) == UVC_VC_EXTENSION_UNIT)
+		return;
+
+	for (i = 0; i < ARRAY_SIZE(uvc_ctrls); ++i) {
+		const struct uvc_control_info *info = &uvc_ctrls[i];
+
+		if (uvc_entity_match_guid(ctrl->entity, info->entity) &&
+		    ctrl->index == info->index) {
+			uvc_ctrl_add_info(chain->dev, ctrl, info);
+			/*
+			 * Retrieve control flags from the device. Ignore errors
+			 * and work with default flag values from the uvc_ctrl
+			 * array when the device doesn't properly implement
+			 * GET_INFO on standard controls.
+			 */
+			uvc_ctrl_get_flags(chain->dev, ctrl, &ctrl->info);
+			break;
+		 }
+	}
+
+	if (!ctrl->initialized)
+		return;
+
+	/*
+	 * First check if the device provides a custom mapping for this control,
+	 * used to override standard mappings for non-conformant devices. Don't
+	 * process standard mappings if a custom mapping is found. This
+	 * mechanism doesn't support combining standard and custom mappings for
+	 * a single control.
+	 */
+	if (chain->dev->info->mappings) {
+		bool custom = false;
+
+		for (i = 0; chain->dev->info->mappings[i]; ++i) {
+			const struct uvc_control_mapping *mapping =
+				chain->dev->info->mappings[i];
+
+			if (uvc_entity_match_guid(ctrl->entity, mapping->entity) &&
+			    ctrl->info.selector == mapping->selector) {
+				__uvc_ctrl_add_mapping(chain, ctrl, mapping);
+				custom = true;
+			}
+		}
+
+		if (custom)
+			return;
+	}
+
+	/* Process common mappings next. */
+	for (i = 0; i < ARRAY_SIZE(uvc_ctrl_mappings); ++i) {
+		const struct uvc_control_mapping *mapping = &uvc_ctrl_mappings[i];
+
+		if (uvc_entity_match_guid(ctrl->entity, mapping->entity) &&
+		    ctrl->info.selector == mapping->selector)
+			__uvc_ctrl_add_mapping(chain, ctrl, mapping);
+	}
+
+	/* Finally process version-specific mappings. */
+	mappings = chain->dev->uvc_version < 0x0150
+		 ? uvc_ctrl_mappings_uvc11 : uvc_ctrl_mappings_uvc15;
+
+	for (i = 0; mappings[i]; ++i) {
+		const struct uvc_control_mapping *mapping = mappings[i];
+
+		if (uvc_entity_match_guid(ctrl->entity, mapping->entity) &&
+		    ctrl->info.selector == mapping->selector)
+			__uvc_ctrl_add_mapping(chain, ctrl, mapping);
+	}
+}
+
+/*
+ * Initialize device controls.
+ */
+static int uvc_ctrl_init_chain(struct uvc_video_chain *chain)
+{
+	struct uvc_entity *entity;
+	unsigned int i;
+
+	/* Walk the entities list and instantiate controls */
+	list_for_each_entry(entity, &chain->entities, chain) {
+		struct uvc_control *ctrl;
+		unsigned int bControlSize = 0, ncontrols;
+		u8 *bmControls = NULL;
+
+		if (UVC_ENTITY_TYPE(entity) == UVC_VC_EXTENSION_UNIT) {
+			bmControls = entity->extension.bmControls;
+			bControlSize = entity->extension.bControlSize;
+		} else if (UVC_ENTITY_TYPE(entity) == UVC_VC_PROCESSING_UNIT) {
+			bmControls = entity->processing.bmControls;
+			bControlSize = entity->processing.bControlSize;
+		} else if (UVC_ENTITY_TYPE(entity) == UVC_ITT_CAMERA) {
+			bmControls = entity->camera.bmControls;
+			bControlSize = entity->camera.bControlSize;
+		} else if (UVC_ENTITY_TYPE(entity) == UVC_EXT_GPIO_UNIT) {
+			bmControls = entity->gpio.bmControls;
+			bControlSize = entity->gpio.bControlSize;
+		}
+
+		/* Remove bogus/blacklisted controls */
+		uvc_ctrl_prune_entity(chain->dev, entity);
+
+		/* Count supported controls and allocate the controls array */
+		ncontrols = memweight(bmControls, bControlSize);
+		if (ncontrols == 0)
+			continue;
+
+		entity->controls = kcalloc(ncontrols, sizeof(*ctrl),
+					   GFP_KERNEL);
+		if (entity->controls == NULL)
+			return -ENOMEM;
+		entity->ncontrols = ncontrols;
+
+		/* Initialize all supported controls */
+		ctrl = entity->controls;
+		for (i = 0; i < bControlSize * 8; ++i) {
+			if (uvc_test_bit(bmControls, i) == 0)
+				continue;
+
+			ctrl->entity = entity;
+			ctrl->index = i;
+
+			uvc_ctrl_init_ctrl(chain, ctrl);
+			ctrl++;
+		}
+	}
+
+	return 0;
+}
+
+int uvc_ctrl_init_device(struct uvc_device *dev)
+{
+	struct uvc_video_chain *chain;
+	int ret;
+
+	INIT_WORK(&dev->async_ctrl.work, uvc_ctrl_status_event_work);
+
+	list_for_each_entry(chain, &dev->chains, list) {
+		ret = uvc_ctrl_init_chain(chain);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+/*
+ * Cleanup device controls.
+ */
+static void uvc_ctrl_cleanup_mappings(struct uvc_device *dev,
+	struct uvc_control *ctrl)
+{
+	struct uvc_control_mapping *mapping, *nm;
+
+	list_for_each_entry_safe(mapping, nm, &ctrl->info.mappings, list) {
+		list_del(&mapping->list);
+		kfree(mapping->menu_names);
+		kfree(mapping->menu_mapping);
+		kfree(mapping->name);
+		kfree(mapping);
+	}
+}
+
+void uvc_ctrl_cleanup_device(struct uvc_device *dev)
+{
+	struct uvc_entity *entity;
+	unsigned int i;
+
+	/* Can be uninitialized if we are aborting on probe error. */
+	if (dev->async_ctrl.work.func)
+		cancel_work_sync(&dev->async_ctrl.work);
+
+	/* Free controls and control mappings for all entities. */
+	list_for_each_entry(entity, &dev->entities, list) {
+		for (i = 0; i < entity->ncontrols; ++i) {
+			struct uvc_control *ctrl = &entity->controls[i];
+
+			if (!ctrl->initialized)
+				continue;
+
+			uvc_ctrl_cleanup_mappings(dev, ctrl);
+			kfree(ctrl->uvc_data);
+		}
+
+		kfree(entity->controls);
+	}
+}
diff --git a/drivers/media/usb/uvc/uvc_debugfs.c b/drivers/media/usb/uvc/uvc_debugfs.c
new file mode 100644
index 000000000..1a1258d4f
--- /dev/null
+++ b/drivers/media/usb/uvc/uvc_debugfs.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *      uvc_debugfs.c --  USB Video Class driver - Debugging support
+ *
+ *      Copyright (C) 2011
+ *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ */
+
+#include <linux/module.h>
+#include <linux/debugfs.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+
+#include "uvcvideo.h"
+
+/* -----------------------------------------------------------------------------
+ * Statistics
+ */
+
+#define UVC_DEBUGFS_BUF_SIZE	1024
+
+struct uvc_debugfs_buffer {
+	size_t count;
+	char data[UVC_DEBUGFS_BUF_SIZE];
+};
+
+static int uvc_debugfs_stats_open(struct inode *inode, struct file *file)
+{
+	struct uvc_streaming *stream = inode->i_private;
+	struct uvc_debugfs_buffer *buf;
+
+	buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+	if (buf == NULL)
+		return -ENOMEM;
+
+	buf->count = uvc_video_stats_dump(stream, buf->data, sizeof(buf->data));
+
+	file->private_data = buf;
+	return 0;
+}
+
+static ssize_t uvc_debugfs_stats_read(struct file *file, char __user *user_buf,
+				      size_t nbytes, loff_t *ppos)
+{
+	struct uvc_debugfs_buffer *buf = file->private_data;
+
+	return simple_read_from_buffer(user_buf, nbytes, ppos, buf->data,
+				       buf->count);
+}
+
+static int uvc_debugfs_stats_release(struct inode *inode, struct file *file)
+{
+	kfree(file->private_data);
+	file->private_data = NULL;
+
+	return 0;
+}
+
+static const struct file_operations uvc_debugfs_stats_fops = {
+	.owner = THIS_MODULE,
+	.open = uvc_debugfs_stats_open,
+	.llseek = no_llseek,
+	.read = uvc_debugfs_stats_read,
+	.release = uvc_debugfs_stats_release,
+};
+
+/* -----------------------------------------------------------------------------
+ * Global and stream initialization/cleanup
+ */
+
+static struct dentry *uvc_debugfs_root_dir;
+
+void uvc_debugfs_init_stream(struct uvc_streaming *stream)
+{
+	struct usb_device *udev = stream->dev->udev;
+	char dir_name[33];
+
+	if (uvc_debugfs_root_dir == NULL)
+		return;
+
+	snprintf(dir_name, sizeof(dir_name), "%u-%u-%u", udev->bus->busnum,
+		 udev->devnum, stream->intfnum);
+
+	stream->debugfs_dir = debugfs_create_dir(dir_name,
+						 uvc_debugfs_root_dir);
+
+	debugfs_create_file("stats", 0444, stream->debugfs_dir, stream,
+			    &uvc_debugfs_stats_fops);
+}
+
+void uvc_debugfs_cleanup_stream(struct uvc_streaming *stream)
+{
+	debugfs_remove_recursive(stream->debugfs_dir);
+	stream->debugfs_dir = NULL;
+}
+
+void uvc_debugfs_init(void)
+{
+	uvc_debugfs_root_dir = debugfs_create_dir("uvcvideo", usb_debug_root);
+}
+
+void uvc_debugfs_cleanup(void)
+{
+	debugfs_remove_recursive(uvc_debugfs_root_dir);
+}
diff --git a/drivers/media/usb/uvc/uvc_driver.c b/drivers/media/usb/uvc/uvc_driver.c
new file mode 100644
index 000000000..08fcd2ffa
--- /dev/null
+++ b/drivers/media/usb/uvc/uvc_driver.c
@@ -0,0 +1,3154 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *      uvc_driver.c  --  USB Video Class driver
+ *
+ *      Copyright (C) 2005-2010
+ *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ */
+
+#include <linux/atomic.h>
+#include <linux/bits.h>
+#include <linux/gpio/consumer.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/usb/uvc.h>
+#include <linux/videodev2.h>
+#include <linux/vmalloc.h>
+#include <linux/wait.h>
+#include <asm/unaligned.h>
+
+#include <media/v4l2-common.h>
+#include <media/v4l2-ioctl.h>
+
+#include "uvcvideo.h"
+
+#define DRIVER_AUTHOR		"Laurent Pinchart " \
+				"<laurent.pinchart@ideasonboard.com>"
+#define DRIVER_DESC		"USB Video Class driver"
+
+unsigned int uvc_clock_param = CLOCK_MONOTONIC;
+unsigned int uvc_hw_timestamps_param;
+unsigned int uvc_no_drop_param;
+static unsigned int uvc_quirks_param = -1;
+unsigned int uvc_dbg_param;
+unsigned int uvc_timeout_param = UVC_CTRL_STREAMING_TIMEOUT;
+
+/* ------------------------------------------------------------------------
+ * Utility functions
+ */
+
+struct usb_host_endpoint *uvc_find_endpoint(struct usb_host_interface *alts,
+		u8 epaddr)
+{
+	struct usb_host_endpoint *ep;
+	unsigned int i;
+
+	for (i = 0; i < alts->desc.bNumEndpoints; ++i) {
+		ep = &alts->endpoint[i];
+		if (ep->desc.bEndpointAddress == epaddr)
+			return ep;
+	}
+
+	return NULL;
+}
+
+static enum v4l2_colorspace uvc_colorspace(const u8 primaries)
+{
+	static const enum v4l2_colorspace colorprimaries[] = {
+		V4L2_COLORSPACE_SRGB,  /* Unspecified */
+		V4L2_COLORSPACE_SRGB,
+		V4L2_COLORSPACE_470_SYSTEM_M,
+		V4L2_COLORSPACE_470_SYSTEM_BG,
+		V4L2_COLORSPACE_SMPTE170M,
+		V4L2_COLORSPACE_SMPTE240M,
+	};
+
+	if (primaries < ARRAY_SIZE(colorprimaries))
+		return colorprimaries[primaries];
+
+	return V4L2_COLORSPACE_SRGB;  /* Reserved */
+}
+
+static enum v4l2_xfer_func uvc_xfer_func(const u8 transfer_characteristics)
+{
+	/*
+	 * V4L2 does not currently have definitions for all possible values of
+	 * UVC transfer characteristics. If v4l2_xfer_func is extended with new
+	 * values, the mapping below should be updated.
+	 *
+	 * Substitutions are taken from the mapping given for
+	 * V4L2_XFER_FUNC_DEFAULT documented in videodev2.h.
+	 */
+	static const enum v4l2_xfer_func xfer_funcs[] = {
+		V4L2_XFER_FUNC_DEFAULT,    /* Unspecified */
+		V4L2_XFER_FUNC_709,
+		V4L2_XFER_FUNC_709,        /* Substitution for BT.470-2 M */
+		V4L2_XFER_FUNC_709,        /* Substitution for BT.470-2 B, G */
+		V4L2_XFER_FUNC_709,        /* Substitution for SMPTE 170M */
+		V4L2_XFER_FUNC_SMPTE240M,
+		V4L2_XFER_FUNC_NONE,
+		V4L2_XFER_FUNC_SRGB,
+	};
+
+	if (transfer_characteristics < ARRAY_SIZE(xfer_funcs))
+		return xfer_funcs[transfer_characteristics];
+
+	return V4L2_XFER_FUNC_DEFAULT;  /* Reserved */
+}
+
+static enum v4l2_ycbcr_encoding uvc_ycbcr_enc(const u8 matrix_coefficients)
+{
+	/*
+	 * V4L2 does not currently have definitions for all possible values of
+	 * UVC matrix coefficients. If v4l2_ycbcr_encoding is extended with new
+	 * values, the mapping below should be updated.
+	 *
+	 * Substitutions are taken from the mapping given for
+	 * V4L2_YCBCR_ENC_DEFAULT documented in videodev2.h.
+	 *
+	 * FCC is assumed to be close enough to 601.
+	 */
+	static const enum v4l2_ycbcr_encoding ycbcr_encs[] = {
+		V4L2_YCBCR_ENC_DEFAULT,  /* Unspecified */
+		V4L2_YCBCR_ENC_709,
+		V4L2_YCBCR_ENC_601,      /* Substitution for FCC */
+		V4L2_YCBCR_ENC_601,      /* Substitution for BT.470-2 B, G */
+		V4L2_YCBCR_ENC_601,
+		V4L2_YCBCR_ENC_SMPTE240M,
+	};
+
+	if (matrix_coefficients < ARRAY_SIZE(ycbcr_encs))
+		return ycbcr_encs[matrix_coefficients];
+
+	return V4L2_YCBCR_ENC_DEFAULT;  /* Reserved */
+}
+
+/* ------------------------------------------------------------------------
+ * Terminal and unit management
+ */
+
+struct uvc_entity *uvc_entity_by_id(struct uvc_device *dev, int id)
+{
+	struct uvc_entity *entity;
+
+	list_for_each_entry(entity, &dev->entities, list) {
+		if (entity->id == id)
+			return entity;
+	}
+
+	return NULL;
+}
+
+static struct uvc_entity *uvc_entity_by_reference(struct uvc_device *dev,
+	int id, struct uvc_entity *entity)
+{
+	unsigned int i;
+
+	if (entity == NULL)
+		entity = list_entry(&dev->entities, struct uvc_entity, list);
+
+	list_for_each_entry_continue(entity, &dev->entities, list) {
+		for (i = 0; i < entity->bNrInPins; ++i)
+			if (entity->baSourceID[i] == id)
+				return entity;
+	}
+
+	return NULL;
+}
+
+static struct uvc_streaming *uvc_stream_by_id(struct uvc_device *dev, int id)
+{
+	struct uvc_streaming *stream;
+
+	list_for_each_entry(stream, &dev->streams, list) {
+		if (stream->header.bTerminalLink == id)
+			return stream;
+	}
+
+	return NULL;
+}
+
+/* ------------------------------------------------------------------------
+ * Streaming Object Management
+ */
+
+static void uvc_stream_delete(struct uvc_streaming *stream)
+{
+	if (stream->async_wq)
+		destroy_workqueue(stream->async_wq);
+
+	mutex_destroy(&stream->mutex);
+
+	usb_put_intf(stream->intf);
+
+	kfree(stream->formats);
+	kfree(stream->header.bmaControls);
+	kfree(stream);
+}
+
+static struct uvc_streaming *uvc_stream_new(struct uvc_device *dev,
+					    struct usb_interface *intf)
+{
+	struct uvc_streaming *stream;
+
+	stream = kzalloc(sizeof(*stream), GFP_KERNEL);
+	if (stream == NULL)
+		return NULL;
+
+	mutex_init(&stream->mutex);
+
+	stream->dev = dev;
+	stream->intf = usb_get_intf(intf);
+	stream->intfnum = intf->cur_altsetting->desc.bInterfaceNumber;
+
+	/* Allocate a stream specific work queue for asynchronous tasks. */
+	stream->async_wq = alloc_workqueue("uvcvideo", WQ_UNBOUND | WQ_HIGHPRI,
+					   0);
+	if (!stream->async_wq) {
+		uvc_stream_delete(stream);
+		return NULL;
+	}
+
+	return stream;
+}
+
+/* ------------------------------------------------------------------------
+ * Descriptors parsing
+ */
+
+static int uvc_parse_format(struct uvc_device *dev,
+	struct uvc_streaming *streaming, struct uvc_format *format,
+	struct uvc_frame *frames, u32 **intervals, const unsigned char *buffer,
+	int buflen)
+{
+	struct usb_interface *intf = streaming->intf;
+	struct usb_host_interface *alts = intf->cur_altsetting;
+	const struct uvc_format_desc *fmtdesc;
+	struct uvc_frame *frame;
+	const unsigned char *start = buffer;
+	unsigned int width_multiplier = 1;
+	unsigned int interval;
+	unsigned int i, n;
+	u8 ftype;
+
+	format->type = buffer[2];
+	format->index = buffer[3];
+	format->frames = frames;
+
+	switch (buffer[2]) {
+	case UVC_VS_FORMAT_UNCOMPRESSED:
+	case UVC_VS_FORMAT_FRAME_BASED:
+		n = buffer[2] == UVC_VS_FORMAT_UNCOMPRESSED ? 27 : 28;
+		if (buflen < n) {
+			uvc_dbg(dev, DESCR,
+				"device %d videostreaming interface %d FORMAT error\n",
+				dev->udev->devnum,
+				alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		/* Find the format descriptor from its GUID. */
+		fmtdesc = uvc_format_by_guid(&buffer[5]);
+
+		if (!fmtdesc) {
+			/*
+			 * Unknown video formats are not fatal errors, the
+			 * caller will skip this descriptor.
+			 */
+			dev_info(&streaming->intf->dev,
+				 "Unknown video format %pUl\n", &buffer[5]);
+			return 0;
+		}
+
+		format->fcc = fmtdesc->fcc;
+		format->bpp = buffer[21];
+
+		/*
+		 * Some devices report a format that doesn't match what they
+		 * really send.
+		 */
+		if (dev->quirks & UVC_QUIRK_FORCE_Y8) {
+			if (format->fcc == V4L2_PIX_FMT_YUYV) {
+				format->fcc = V4L2_PIX_FMT_GREY;
+				format->bpp = 8;
+				width_multiplier = 2;
+			}
+		}
+
+		/* Some devices report bpp that doesn't match the format. */
+		if (dev->quirks & UVC_QUIRK_FORCE_BPP) {
+			const struct v4l2_format_info *info =
+				v4l2_format_info(format->fcc);
+
+			if (info) {
+				unsigned int div = info->hdiv * info->vdiv;
+
+				n = info->bpp[0] * div;
+				for (i = 1; i < info->comp_planes; i++)
+					n += info->bpp[i];
+
+				format->bpp = DIV_ROUND_UP(8 * n, div);
+			}
+		}
+
+		if (buffer[2] == UVC_VS_FORMAT_UNCOMPRESSED) {
+			ftype = UVC_VS_FRAME_UNCOMPRESSED;
+		} else {
+			ftype = UVC_VS_FRAME_FRAME_BASED;
+			if (buffer[27])
+				format->flags = UVC_FMT_FLAG_COMPRESSED;
+		}
+		break;
+
+	case UVC_VS_FORMAT_MJPEG:
+		if (buflen < 11) {
+			uvc_dbg(dev, DESCR,
+				"device %d videostreaming interface %d FORMAT error\n",
+				dev->udev->devnum,
+				alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		format->fcc = V4L2_PIX_FMT_MJPEG;
+		format->flags = UVC_FMT_FLAG_COMPRESSED;
+		format->bpp = 0;
+		ftype = UVC_VS_FRAME_MJPEG;
+		break;
+
+	case UVC_VS_FORMAT_DV:
+		if (buflen < 9) {
+			uvc_dbg(dev, DESCR,
+				"device %d videostreaming interface %d FORMAT error\n",
+				dev->udev->devnum,
+				alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		if ((buffer[8] & 0x7f) > 2) {
+			uvc_dbg(dev, DESCR,
+				"device %d videostreaming interface %d: unknown DV format %u\n",
+				dev->udev->devnum,
+				alts->desc.bInterfaceNumber, buffer[8]);
+			return -EINVAL;
+		}
+
+		format->fcc = V4L2_PIX_FMT_DV;
+		format->flags = UVC_FMT_FLAG_COMPRESSED | UVC_FMT_FLAG_STREAM;
+		format->bpp = 0;
+		ftype = 0;
+
+		/* Create a dummy frame descriptor. */
+		frame = &frames[0];
+		memset(frame, 0, sizeof(*frame));
+		frame->bFrameIntervalType = 1;
+		frame->dwDefaultFrameInterval = 1;
+		frame->dwFrameInterval = *intervals;
+		*(*intervals)++ = 1;
+		format->nframes = 1;
+		break;
+
+	case UVC_VS_FORMAT_MPEG2TS:
+	case UVC_VS_FORMAT_STREAM_BASED:
+		/* Not supported yet. */
+	default:
+		uvc_dbg(dev, DESCR,
+			"device %d videostreaming interface %d unsupported format %u\n",
+			dev->udev->devnum, alts->desc.bInterfaceNumber,
+			buffer[2]);
+		return -EINVAL;
+	}
+
+	uvc_dbg(dev, DESCR, "Found format %p4cc", &format->fcc);
+
+	buflen -= buffer[0];
+	buffer += buffer[0];
+
+	/*
+	 * Parse the frame descriptors. Only uncompressed, MJPEG and frame
+	 * based formats have frame descriptors.
+	 */
+	while (buflen > 2 && buffer[1] == USB_DT_CS_INTERFACE &&
+	       buffer[2] == ftype) {
+		unsigned int maxIntervalIndex;
+
+		frame = &frames[format->nframes];
+		if (ftype != UVC_VS_FRAME_FRAME_BASED)
+			n = buflen > 25 ? buffer[25] : 0;
+		else
+			n = buflen > 21 ? buffer[21] : 0;
+
+		n = n ? n : 3;
+
+		if (buflen < 26 + 4*n) {
+			uvc_dbg(dev, DESCR,
+				"device %d videostreaming interface %d FRAME error\n",
+				dev->udev->devnum,
+				alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		frame->bFrameIndex = buffer[3];
+		frame->bmCapabilities = buffer[4];
+		frame->wWidth = get_unaligned_le16(&buffer[5])
+			      * width_multiplier;
+		frame->wHeight = get_unaligned_le16(&buffer[7]);
+		frame->dwMinBitRate = get_unaligned_le32(&buffer[9]);
+		frame->dwMaxBitRate = get_unaligned_le32(&buffer[13]);
+		if (ftype != UVC_VS_FRAME_FRAME_BASED) {
+			frame->dwMaxVideoFrameBufferSize =
+				get_unaligned_le32(&buffer[17]);
+			frame->dwDefaultFrameInterval =
+				get_unaligned_le32(&buffer[21]);
+			frame->bFrameIntervalType = buffer[25];
+		} else {
+			frame->dwMaxVideoFrameBufferSize = 0;
+			frame->dwDefaultFrameInterval =
+				get_unaligned_le32(&buffer[17]);
+			frame->bFrameIntervalType = buffer[21];
+		}
+
+		/*
+		 * Copy the frame intervals.
+		 *
+		 * Some bogus devices report dwMinFrameInterval equal to
+		 * dwMaxFrameInterval and have dwFrameIntervalStep set to
+		 * zero. Setting all null intervals to 1 fixes the problem and
+		 * some other divisions by zero that could happen.
+		 */
+		frame->dwFrameInterval = *intervals;
+
+		for (i = 0; i < n; ++i) {
+			interval = get_unaligned_le32(&buffer[26+4*i]);
+			(*intervals)[i] = interval ? interval : 1;
+		}
+
+		/*
+		 * Apply more fixes, quirks and workarounds to handle incorrect
+		 * or broken descriptors.
+		 */
+
+		/*
+		 * Several UVC chipsets screw up dwMaxVideoFrameBufferSize
+		 * completely. Observed behaviours range from setting the
+		 * value to 1.1x the actual frame size to hardwiring the
+		 * 16 low bits to 0. This results in a higher than necessary
+		 * memory usage as well as a wrong image size information. For
+		 * uncompressed formats this can be fixed by computing the
+		 * value from the frame size.
+		 */
+		if (!(format->flags & UVC_FMT_FLAG_COMPRESSED))
+			frame->dwMaxVideoFrameBufferSize = format->bpp
+				* frame->wWidth * frame->wHeight / 8;
+
+		/*
+		 * Clamp the default frame interval to the boundaries. A zero
+		 * bFrameIntervalType value indicates a continuous frame
+		 * interval range, with dwFrameInterval[0] storing the minimum
+		 * value and dwFrameInterval[1] storing the maximum value.
+		 */
+		maxIntervalIndex = frame->bFrameIntervalType ? n - 1 : 1;
+		frame->dwDefaultFrameInterval =
+			clamp(frame->dwDefaultFrameInterval,
+			      frame->dwFrameInterval[0],
+			      frame->dwFrameInterval[maxIntervalIndex]);
+
+		/*
+		 * Some devices report frame intervals that are not functional.
+		 * If the corresponding quirk is set, restrict operation to the
+		 * first interval only.
+		 */
+		if (dev->quirks & UVC_QUIRK_RESTRICT_FRAME_RATE) {
+			frame->bFrameIntervalType = 1;
+			(*intervals)[0] = frame->dwDefaultFrameInterval;
+		}
+
+		uvc_dbg(dev, DESCR, "- %ux%u (%u.%u fps)\n",
+			frame->wWidth, frame->wHeight,
+			10000000 / frame->dwDefaultFrameInterval,
+			(100000000 / frame->dwDefaultFrameInterval) % 10);
+
+		format->nframes++;
+		*intervals += n;
+
+		buflen -= buffer[0];
+		buffer += buffer[0];
+	}
+
+	if (buflen > 2 && buffer[1] == USB_DT_CS_INTERFACE &&
+	    buffer[2] == UVC_VS_STILL_IMAGE_FRAME) {
+		buflen -= buffer[0];
+		buffer += buffer[0];
+	}
+
+	if (buflen > 2 && buffer[1] == USB_DT_CS_INTERFACE &&
+	    buffer[2] == UVC_VS_COLORFORMAT) {
+		if (buflen < 6) {
+			uvc_dbg(dev, DESCR,
+				"device %d videostreaming interface %d COLORFORMAT error\n",
+				dev->udev->devnum,
+				alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		format->colorspace = uvc_colorspace(buffer[3]);
+		format->xfer_func = uvc_xfer_func(buffer[4]);
+		format->ycbcr_enc = uvc_ycbcr_enc(buffer[5]);
+
+		buflen -= buffer[0];
+		buffer += buffer[0];
+	} else {
+		format->colorspace = V4L2_COLORSPACE_SRGB;
+	}
+
+	return buffer - start;
+}
+
+static int uvc_parse_streaming(struct uvc_device *dev,
+	struct usb_interface *intf)
+{
+	struct uvc_streaming *streaming = NULL;
+	struct uvc_format *format;
+	struct uvc_frame *frame;
+	struct usb_host_interface *alts = &intf->altsetting[0];
+	const unsigned char *_buffer, *buffer = alts->extra;
+	int _buflen, buflen = alts->extralen;
+	unsigned int nformats = 0, nframes = 0, nintervals = 0;
+	unsigned int size, i, n, p;
+	u32 *interval;
+	u16 psize;
+	int ret = -EINVAL;
+
+	if (intf->cur_altsetting->desc.bInterfaceSubClass
+		!= UVC_SC_VIDEOSTREAMING) {
+		uvc_dbg(dev, DESCR,
+			"device %d interface %d isn't a video streaming interface\n",
+			dev->udev->devnum,
+			intf->altsetting[0].desc.bInterfaceNumber);
+		return -EINVAL;
+	}
+
+	if (usb_driver_claim_interface(&uvc_driver.driver, intf, dev)) {
+		uvc_dbg(dev, DESCR,
+			"device %d interface %d is already claimed\n",
+			dev->udev->devnum,
+			intf->altsetting[0].desc.bInterfaceNumber);
+		return -EINVAL;
+	}
+
+	streaming = uvc_stream_new(dev, intf);
+	if (streaming == NULL) {
+		usb_driver_release_interface(&uvc_driver.driver, intf);
+		return -ENOMEM;
+	}
+
+	/*
+	 * The Pico iMage webcam has its class-specific interface descriptors
+	 * after the endpoint descriptors.
+	 */
+	if (buflen == 0) {
+		for (i = 0; i < alts->desc.bNumEndpoints; ++i) {
+			struct usb_host_endpoint *ep = &alts->endpoint[i];
+
+			if (ep->extralen == 0)
+				continue;
+
+			if (ep->extralen > 2 &&
+			    ep->extra[1] == USB_DT_CS_INTERFACE) {
+				uvc_dbg(dev, DESCR,
+					"trying extra data from endpoint %u\n",
+					i);
+				buffer = alts->endpoint[i].extra;
+				buflen = alts->endpoint[i].extralen;
+				break;
+			}
+		}
+	}
+
+	/* Skip the standard interface descriptors. */
+	while (buflen > 2 && buffer[1] != USB_DT_CS_INTERFACE) {
+		buflen -= buffer[0];
+		buffer += buffer[0];
+	}
+
+	if (buflen <= 2) {
+		uvc_dbg(dev, DESCR,
+			"no class-specific streaming interface descriptors found\n");
+		goto error;
+	}
+
+	/* Parse the header descriptor. */
+	switch (buffer[2]) {
+	case UVC_VS_OUTPUT_HEADER:
+		streaming->type = V4L2_BUF_TYPE_VIDEO_OUTPUT;
+		size = 9;
+		break;
+
+	case UVC_VS_INPUT_HEADER:
+		streaming->type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
+		size = 13;
+		break;
+
+	default:
+		uvc_dbg(dev, DESCR,
+			"device %d videostreaming interface %d HEADER descriptor not found\n",
+			dev->udev->devnum, alts->desc.bInterfaceNumber);
+		goto error;
+	}
+
+	p = buflen >= 4 ? buffer[3] : 0;
+	n = buflen >= size ? buffer[size-1] : 0;
+
+	if (buflen < size + p*n) {
+		uvc_dbg(dev, DESCR,
+			"device %d videostreaming interface %d HEADER descriptor is invalid\n",
+			dev->udev->devnum, alts->desc.bInterfaceNumber);
+		goto error;
+	}
+
+	streaming->header.bNumFormats = p;
+	streaming->header.bEndpointAddress = buffer[6];
+	if (buffer[2] == UVC_VS_INPUT_HEADER) {
+		streaming->header.bmInfo = buffer[7];
+		streaming->header.bTerminalLink = buffer[8];
+		streaming->header.bStillCaptureMethod = buffer[9];
+		streaming->header.bTriggerSupport = buffer[10];
+		streaming->header.bTriggerUsage = buffer[11];
+	} else {
+		streaming->header.bTerminalLink = buffer[7];
+	}
+	streaming->header.bControlSize = n;
+
+	streaming->header.bmaControls = kmemdup(&buffer[size], p * n,
+						GFP_KERNEL);
+	if (streaming->header.bmaControls == NULL) {
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	buflen -= buffer[0];
+	buffer += buffer[0];
+
+	_buffer = buffer;
+	_buflen = buflen;
+
+	/* Count the format and frame descriptors. */
+	while (_buflen > 2 && _buffer[1] == USB_DT_CS_INTERFACE) {
+		switch (_buffer[2]) {
+		case UVC_VS_FORMAT_UNCOMPRESSED:
+		case UVC_VS_FORMAT_MJPEG:
+		case UVC_VS_FORMAT_FRAME_BASED:
+			nformats++;
+			break;
+
+		case UVC_VS_FORMAT_DV:
+			/*
+			 * DV format has no frame descriptor. We will create a
+			 * dummy frame descriptor with a dummy frame interval.
+			 */
+			nformats++;
+			nframes++;
+			nintervals++;
+			break;
+
+		case UVC_VS_FORMAT_MPEG2TS:
+		case UVC_VS_FORMAT_STREAM_BASED:
+			uvc_dbg(dev, DESCR,
+				"device %d videostreaming interface %d FORMAT %u is not supported\n",
+				dev->udev->devnum,
+				alts->desc.bInterfaceNumber, _buffer[2]);
+			break;
+
+		case UVC_VS_FRAME_UNCOMPRESSED:
+		case UVC_VS_FRAME_MJPEG:
+			nframes++;
+			if (_buflen > 25)
+				nintervals += _buffer[25] ? _buffer[25] : 3;
+			break;
+
+		case UVC_VS_FRAME_FRAME_BASED:
+			nframes++;
+			if (_buflen > 21)
+				nintervals += _buffer[21] ? _buffer[21] : 3;
+			break;
+		}
+
+		_buflen -= _buffer[0];
+		_buffer += _buffer[0];
+	}
+
+	if (nformats == 0) {
+		uvc_dbg(dev, DESCR,
+			"device %d videostreaming interface %d has no supported formats defined\n",
+			dev->udev->devnum, alts->desc.bInterfaceNumber);
+		goto error;
+	}
+
+	size = nformats * sizeof(*format) + nframes * sizeof(*frame)
+	     + nintervals * sizeof(*interval);
+	format = kzalloc(size, GFP_KERNEL);
+	if (format == NULL) {
+		ret = -ENOMEM;
+		goto error;
+	}
+
+	frame = (struct uvc_frame *)&format[nformats];
+	interval = (u32 *)&frame[nframes];
+
+	streaming->formats = format;
+	streaming->nformats = 0;
+
+	/* Parse the format descriptors. */
+	while (buflen > 2 && buffer[1] == USB_DT_CS_INTERFACE) {
+		switch (buffer[2]) {
+		case UVC_VS_FORMAT_UNCOMPRESSED:
+		case UVC_VS_FORMAT_MJPEG:
+		case UVC_VS_FORMAT_DV:
+		case UVC_VS_FORMAT_FRAME_BASED:
+			ret = uvc_parse_format(dev, streaming, format, frame,
+				&interval, buffer, buflen);
+			if (ret < 0)
+				goto error;
+			if (!ret)
+				break;
+
+			streaming->nformats++;
+			frame += format->nframes;
+			format++;
+
+			buflen -= ret;
+			buffer += ret;
+			continue;
+
+		default:
+			break;
+		}
+
+		buflen -= buffer[0];
+		buffer += buffer[0];
+	}
+
+	if (buflen)
+		uvc_dbg(dev, DESCR,
+			"device %d videostreaming interface %d has %u bytes of trailing descriptor garbage\n",
+			dev->udev->devnum, alts->desc.bInterfaceNumber, buflen);
+
+	/* Parse the alternate settings to find the maximum bandwidth. */
+	for (i = 0; i < intf->num_altsetting; ++i) {
+		struct usb_host_endpoint *ep;
+
+		alts = &intf->altsetting[i];
+		ep = uvc_find_endpoint(alts,
+				streaming->header.bEndpointAddress);
+		if (ep == NULL)
+			continue;
+		psize = uvc_endpoint_max_bpi(dev->udev, ep);
+		if (psize > streaming->maxpsize)
+			streaming->maxpsize = psize;
+	}
+
+	list_add_tail(&streaming->list, &dev->streams);
+	return 0;
+
+error:
+	usb_driver_release_interface(&uvc_driver.driver, intf);
+	uvc_stream_delete(streaming);
+	return ret;
+}
+
+static const u8 uvc_camera_guid[16] = UVC_GUID_UVC_CAMERA;
+static const u8 uvc_gpio_guid[16] = UVC_GUID_EXT_GPIO_CONTROLLER;
+static const u8 uvc_media_transport_input_guid[16] =
+	UVC_GUID_UVC_MEDIA_TRANSPORT_INPUT;
+static const u8 uvc_processing_guid[16] = UVC_GUID_UVC_PROCESSING;
+
+static struct uvc_entity *uvc_alloc_entity(u16 type, u16 id,
+		unsigned int num_pads, unsigned int extra_size)
+{
+	struct uvc_entity *entity;
+	unsigned int num_inputs;
+	unsigned int size;
+	unsigned int i;
+
+	extra_size = roundup(extra_size, sizeof(*entity->pads));
+	if (num_pads)
+		num_inputs = type & UVC_TERM_OUTPUT ? num_pads : num_pads - 1;
+	else
+		num_inputs = 0;
+	size = sizeof(*entity) + extra_size + sizeof(*entity->pads) * num_pads
+	     + num_inputs;
+	entity = kzalloc(size, GFP_KERNEL);
+	if (entity == NULL)
+		return NULL;
+
+	entity->id = id;
+	entity->type = type;
+
+	/*
+	 * Set the GUID for standard entity types. For extension units, the GUID
+	 * is initialized by the caller.
+	 */
+	switch (type) {
+	case UVC_EXT_GPIO_UNIT:
+		memcpy(entity->guid, uvc_gpio_guid, 16);
+		break;
+	case UVC_ITT_CAMERA:
+		memcpy(entity->guid, uvc_camera_guid, 16);
+		break;
+	case UVC_ITT_MEDIA_TRANSPORT_INPUT:
+		memcpy(entity->guid, uvc_media_transport_input_guid, 16);
+		break;
+	case UVC_VC_PROCESSING_UNIT:
+		memcpy(entity->guid, uvc_processing_guid, 16);
+		break;
+	}
+
+	entity->num_links = 0;
+	entity->num_pads = num_pads;
+	entity->pads = ((void *)(entity + 1)) + extra_size;
+
+	for (i = 0; i < num_inputs; ++i)
+		entity->pads[i].flags = MEDIA_PAD_FL_SINK;
+	if (!UVC_ENTITY_IS_OTERM(entity) && num_pads)
+		entity->pads[num_pads-1].flags = MEDIA_PAD_FL_SOURCE;
+
+	entity->bNrInPins = num_inputs;
+	entity->baSourceID = (u8 *)(&entity->pads[num_pads]);
+
+	return entity;
+}
+
+static void uvc_entity_set_name(struct uvc_device *dev, struct uvc_entity *entity,
+				const char *type_name, u8 string_id)
+{
+	int ret;
+
+	/*
+	 * First attempt to read the entity name from the device. If the entity
+	 * has no associated string, or if reading the string fails (most
+	 * likely due to a buggy firmware), fall back to default names based on
+	 * the entity type.
+	 */
+	if (string_id) {
+		ret = usb_string(dev->udev, string_id, entity->name,
+				 sizeof(entity->name));
+		if (!ret)
+			return;
+	}
+
+	sprintf(entity->name, "%s %u", type_name, entity->id);
+}
+
+/* Parse vendor-specific extensions. */
+static int uvc_parse_vendor_control(struct uvc_device *dev,
+	const unsigned char *buffer, int buflen)
+{
+	struct usb_device *udev = dev->udev;
+	struct usb_host_interface *alts = dev->intf->cur_altsetting;
+	struct uvc_entity *unit;
+	unsigned int n, p;
+	int handled = 0;
+
+	switch (le16_to_cpu(dev->udev->descriptor.idVendor)) {
+	case 0x046d:		/* Logitech */
+		if (buffer[1] != 0x41 || buffer[2] != 0x01)
+			break;
+
+		/*
+		 * Logitech implements several vendor specific functions
+		 * through vendor specific extension units (LXU).
+		 *
+		 * The LXU descriptors are similar to XU descriptors
+		 * (see "USB Device Video Class for Video Devices", section
+		 * 3.7.2.6 "Extension Unit Descriptor") with the following
+		 * differences:
+		 *
+		 * ----------------------------------------------------------
+		 * 0		bLength		1	 Number
+		 *	Size of this descriptor, in bytes: 24+p+n*2
+		 * ----------------------------------------------------------
+		 * 23+p+n	bmControlsType	N	Bitmap
+		 *	Individual bits in the set are defined:
+		 *	0: Absolute
+		 *	1: Relative
+		 *
+		 *	This bitset is mapped exactly the same as bmControls.
+		 * ----------------------------------------------------------
+		 * 23+p+n*2	bReserved	1	Boolean
+		 * ----------------------------------------------------------
+		 * 24+p+n*2	iExtension	1	Index
+		 *	Index of a string descriptor that describes this
+		 *	extension unit.
+		 * ----------------------------------------------------------
+		 */
+		p = buflen >= 22 ? buffer[21] : 0;
+		n = buflen >= 25 + p ? buffer[22+p] : 0;
+
+		if (buflen < 25 + p + 2*n) {
+			uvc_dbg(dev, DESCR,
+				"device %d videocontrol interface %d EXTENSION_UNIT error\n",
+				udev->devnum, alts->desc.bInterfaceNumber);
+			break;
+		}
+
+		unit = uvc_alloc_entity(UVC_VC_EXTENSION_UNIT, buffer[3],
+					p + 1, 2*n);
+		if (unit == NULL)
+			return -ENOMEM;
+
+		memcpy(unit->guid, &buffer[4], 16);
+		unit->extension.bNumControls = buffer[20];
+		memcpy(unit->baSourceID, &buffer[22], p);
+		unit->extension.bControlSize = buffer[22+p];
+		unit->extension.bmControls = (u8 *)unit + sizeof(*unit);
+		unit->extension.bmControlsType = (u8 *)unit + sizeof(*unit)
+					       + n;
+		memcpy(unit->extension.bmControls, &buffer[23+p], 2*n);
+
+		uvc_entity_set_name(dev, unit, "Extension", buffer[24+p+2*n]);
+
+		list_add_tail(&unit->list, &dev->entities);
+		handled = 1;
+		break;
+	}
+
+	return handled;
+}
+
+static int uvc_parse_standard_control(struct uvc_device *dev,
+	const unsigned char *buffer, int buflen)
+{
+	struct usb_device *udev = dev->udev;
+	struct uvc_entity *unit, *term;
+	struct usb_interface *intf;
+	struct usb_host_interface *alts = dev->intf->cur_altsetting;
+	unsigned int i, n, p, len;
+	const char *type_name;
+	u16 type;
+
+	switch (buffer[2]) {
+	case UVC_VC_HEADER:
+		n = buflen >= 12 ? buffer[11] : 0;
+
+		if (buflen < 12 + n) {
+			uvc_dbg(dev, DESCR,
+				"device %d videocontrol interface %d HEADER error\n",
+				udev->devnum, alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		dev->uvc_version = get_unaligned_le16(&buffer[3]);
+		dev->clock_frequency = get_unaligned_le32(&buffer[7]);
+
+		/* Parse all USB Video Streaming interfaces. */
+		for (i = 0; i < n; ++i) {
+			intf = usb_ifnum_to_if(udev, buffer[12+i]);
+			if (intf == NULL) {
+				uvc_dbg(dev, DESCR,
+					"device %d interface %d doesn't exists\n",
+					udev->devnum, i);
+				continue;
+			}
+
+			uvc_parse_streaming(dev, intf);
+		}
+		break;
+
+	case UVC_VC_INPUT_TERMINAL:
+		if (buflen < 8) {
+			uvc_dbg(dev, DESCR,
+				"device %d videocontrol interface %d INPUT_TERMINAL error\n",
+				udev->devnum, alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		/*
+		 * Reject invalid terminal types that would cause issues:
+		 *
+		 * - The high byte must be non-zero, otherwise it would be
+		 *   confused with a unit.
+		 *
+		 * - Bit 15 must be 0, as we use it internally as a terminal
+		 *   direction flag.
+		 *
+		 * Other unknown types are accepted.
+		 */
+		type = get_unaligned_le16(&buffer[4]);
+		if ((type & 0x7f00) == 0 || (type & 0x8000) != 0) {
+			uvc_dbg(dev, DESCR,
+				"device %d videocontrol interface %d INPUT_TERMINAL %d has invalid type 0x%04x, skipping\n",
+				udev->devnum, alts->desc.bInterfaceNumber,
+				buffer[3], type);
+			return 0;
+		}
+
+		n = 0;
+		p = 0;
+		len = 8;
+
+		if (type == UVC_ITT_CAMERA) {
+			n = buflen >= 15 ? buffer[14] : 0;
+			len = 15;
+
+		} else if (type == UVC_ITT_MEDIA_TRANSPORT_INPUT) {
+			n = buflen >= 9 ? buffer[8] : 0;
+			p = buflen >= 10 + n ? buffer[9+n] : 0;
+			len = 10;
+		}
+
+		if (buflen < len + n + p) {
+			uvc_dbg(dev, DESCR,
+				"device %d videocontrol interface %d INPUT_TERMINAL error\n",
+				udev->devnum, alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		term = uvc_alloc_entity(type | UVC_TERM_INPUT, buffer[3],
+					1, n + p);
+		if (term == NULL)
+			return -ENOMEM;
+
+		if (UVC_ENTITY_TYPE(term) == UVC_ITT_CAMERA) {
+			term->camera.bControlSize = n;
+			term->camera.bmControls = (u8 *)term + sizeof(*term);
+			term->camera.wObjectiveFocalLengthMin =
+				get_unaligned_le16(&buffer[8]);
+			term->camera.wObjectiveFocalLengthMax =
+				get_unaligned_le16(&buffer[10]);
+			term->camera.wOcularFocalLength =
+				get_unaligned_le16(&buffer[12]);
+			memcpy(term->camera.bmControls, &buffer[15], n);
+		} else if (UVC_ENTITY_TYPE(term) ==
+			   UVC_ITT_MEDIA_TRANSPORT_INPUT) {
+			term->media.bControlSize = n;
+			term->media.bmControls = (u8 *)term + sizeof(*term);
+			term->media.bTransportModeSize = p;
+			term->media.bmTransportModes = (u8 *)term
+						     + sizeof(*term) + n;
+			memcpy(term->media.bmControls, &buffer[9], n);
+			memcpy(term->media.bmTransportModes, &buffer[10+n], p);
+		}
+
+		if (UVC_ENTITY_TYPE(term) == UVC_ITT_CAMERA)
+			type_name = "Camera";
+		else if (UVC_ENTITY_TYPE(term) == UVC_ITT_MEDIA_TRANSPORT_INPUT)
+			type_name = "Media";
+		else
+			type_name = "Input";
+
+		uvc_entity_set_name(dev, term, type_name, buffer[7]);
+
+		list_add_tail(&term->list, &dev->entities);
+		break;
+
+	case UVC_VC_OUTPUT_TERMINAL:
+		if (buflen < 9) {
+			uvc_dbg(dev, DESCR,
+				"device %d videocontrol interface %d OUTPUT_TERMINAL error\n",
+				udev->devnum, alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		/*
+		 * Make sure the terminal type MSB is not null, otherwise it
+		 * could be confused with a unit.
+		 */
+		type = get_unaligned_le16(&buffer[4]);
+		if ((type & 0xff00) == 0) {
+			uvc_dbg(dev, DESCR,
+				"device %d videocontrol interface %d OUTPUT_TERMINAL %d has invalid type 0x%04x, skipping\n",
+				udev->devnum, alts->desc.bInterfaceNumber,
+				buffer[3], type);
+			return 0;
+		}
+
+		term = uvc_alloc_entity(type | UVC_TERM_OUTPUT, buffer[3],
+					1, 0);
+		if (term == NULL)
+			return -ENOMEM;
+
+		memcpy(term->baSourceID, &buffer[7], 1);
+
+		uvc_entity_set_name(dev, term, "Output", buffer[8]);
+
+		list_add_tail(&term->list, &dev->entities);
+		break;
+
+	case UVC_VC_SELECTOR_UNIT:
+		p = buflen >= 5 ? buffer[4] : 0;
+
+		if (buflen < 5 || buflen < 6 + p) {
+			uvc_dbg(dev, DESCR,
+				"device %d videocontrol interface %d SELECTOR_UNIT error\n",
+				udev->devnum, alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		unit = uvc_alloc_entity(buffer[2], buffer[3], p + 1, 0);
+		if (unit == NULL)
+			return -ENOMEM;
+
+		memcpy(unit->baSourceID, &buffer[5], p);
+
+		uvc_entity_set_name(dev, unit, "Selector", buffer[5+p]);
+
+		list_add_tail(&unit->list, &dev->entities);
+		break;
+
+	case UVC_VC_PROCESSING_UNIT:
+		n = buflen >= 8 ? buffer[7] : 0;
+		p = dev->uvc_version >= 0x0110 ? 10 : 9;
+
+		if (buflen < p + n) {
+			uvc_dbg(dev, DESCR,
+				"device %d videocontrol interface %d PROCESSING_UNIT error\n",
+				udev->devnum, alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		unit = uvc_alloc_entity(buffer[2], buffer[3], 2, n);
+		if (unit == NULL)
+			return -ENOMEM;
+
+		memcpy(unit->baSourceID, &buffer[4], 1);
+		unit->processing.wMaxMultiplier =
+			get_unaligned_le16(&buffer[5]);
+		unit->processing.bControlSize = buffer[7];
+		unit->processing.bmControls = (u8 *)unit + sizeof(*unit);
+		memcpy(unit->processing.bmControls, &buffer[8], n);
+		if (dev->uvc_version >= 0x0110)
+			unit->processing.bmVideoStandards = buffer[9+n];
+
+		uvc_entity_set_name(dev, unit, "Processing", buffer[8+n]);
+
+		list_add_tail(&unit->list, &dev->entities);
+		break;
+
+	case UVC_VC_EXTENSION_UNIT:
+		p = buflen >= 22 ? buffer[21] : 0;
+		n = buflen >= 24 + p ? buffer[22+p] : 0;
+
+		if (buflen < 24 + p + n) {
+			uvc_dbg(dev, DESCR,
+				"device %d videocontrol interface %d EXTENSION_UNIT error\n",
+				udev->devnum, alts->desc.bInterfaceNumber);
+			return -EINVAL;
+		}
+
+		unit = uvc_alloc_entity(buffer[2], buffer[3], p + 1, n);
+		if (unit == NULL)
+			return -ENOMEM;
+
+		memcpy(unit->guid, &buffer[4], 16);
+		unit->extension.bNumControls = buffer[20];
+		memcpy(unit->baSourceID, &buffer[22], p);
+		unit->extension.bControlSize = buffer[22+p];
+		unit->extension.bmControls = (u8 *)unit + sizeof(*unit);
+		memcpy(unit->extension.bmControls, &buffer[23+p], n);
+
+		uvc_entity_set_name(dev, unit, "Extension", buffer[23+p+n]);
+
+		list_add_tail(&unit->list, &dev->entities);
+		break;
+
+	default:
+		uvc_dbg(dev, DESCR,
+			"Found an unknown CS_INTERFACE descriptor (%u)\n",
+			buffer[2]);
+		break;
+	}
+
+	return 0;
+}
+
+static int uvc_parse_control(struct uvc_device *dev)
+{
+	struct usb_host_interface *alts = dev->intf->cur_altsetting;
+	const unsigned char *buffer = alts->extra;
+	int buflen = alts->extralen;
+	int ret;
+
+	/*
+	 * Parse the default alternate setting only, as the UVC specification
+	 * defines a single alternate setting, the default alternate setting
+	 * zero.
+	 */
+
+	while (buflen > 2) {
+		if (uvc_parse_vendor_control(dev, buffer, buflen) ||
+		    buffer[1] != USB_DT_CS_INTERFACE)
+			goto next_descriptor;
+
+		ret = uvc_parse_standard_control(dev, buffer, buflen);
+		if (ret < 0)
+			return ret;
+
+next_descriptor:
+		buflen -= buffer[0];
+		buffer += buffer[0];
+	}
+
+	/*
+	 * Check if the optional status endpoint is present. Built-in iSight
+	 * webcams have an interrupt endpoint but spit proprietary data that
+	 * don't conform to the UVC status endpoint messages. Don't try to
+	 * handle the interrupt endpoint for those cameras.
+	 */
+	if (alts->desc.bNumEndpoints == 1 &&
+	    !(dev->quirks & UVC_QUIRK_BUILTIN_ISIGHT)) {
+		struct usb_host_endpoint *ep = &alts->endpoint[0];
+		struct usb_endpoint_descriptor *desc = &ep->desc;
+
+		if (usb_endpoint_is_int_in(desc) &&
+		    le16_to_cpu(desc->wMaxPacketSize) >= 8 &&
+		    desc->bInterval != 0) {
+			uvc_dbg(dev, DESCR,
+				"Found a Status endpoint (addr %02x)\n",
+				desc->bEndpointAddress);
+			dev->int_ep = ep;
+		}
+	}
+
+	return 0;
+}
+
+/* -----------------------------------------------------------------------------
+ * Privacy GPIO
+ */
+
+static void uvc_gpio_event(struct uvc_device *dev)
+{
+	struct uvc_entity *unit = dev->gpio_unit;
+	struct uvc_video_chain *chain;
+	u8 new_val;
+
+	if (!unit)
+		return;
+
+	new_val = gpiod_get_value_cansleep(unit->gpio.gpio_privacy);
+
+	/* GPIO entities are always on the first chain. */
+	chain = list_first_entry(&dev->chains, struct uvc_video_chain, list);
+	uvc_ctrl_status_event(chain, unit->controls, &new_val);
+}
+
+static int uvc_gpio_get_cur(struct uvc_device *dev, struct uvc_entity *entity,
+			    u8 cs, void *data, u16 size)
+{
+	if (cs != UVC_CT_PRIVACY_CONTROL || size < 1)
+		return -EINVAL;
+
+	*(u8 *)data = gpiod_get_value_cansleep(entity->gpio.gpio_privacy);
+
+	return 0;
+}
+
+static int uvc_gpio_get_info(struct uvc_device *dev, struct uvc_entity *entity,
+			     u8 cs, u8 *caps)
+{
+	if (cs != UVC_CT_PRIVACY_CONTROL)
+		return -EINVAL;
+
+	*caps = UVC_CONTROL_CAP_GET | UVC_CONTROL_CAP_AUTOUPDATE;
+	return 0;
+}
+
+static irqreturn_t uvc_gpio_irq(int irq, void *data)
+{
+	struct uvc_device *dev = data;
+
+	uvc_gpio_event(dev);
+	return IRQ_HANDLED;
+}
+
+static int uvc_gpio_parse(struct uvc_device *dev)
+{
+	struct uvc_entity *unit;
+	struct gpio_desc *gpio_privacy;
+	int irq;
+
+	gpio_privacy = devm_gpiod_get_optional(&dev->udev->dev, "privacy",
+					       GPIOD_IN);
+	if (IS_ERR_OR_NULL(gpio_privacy))
+		return PTR_ERR_OR_ZERO(gpio_privacy);
+
+	irq = gpiod_to_irq(gpio_privacy);
+	if (irq < 0)
+		return dev_err_probe(&dev->udev->dev, irq,
+				     "No IRQ for privacy GPIO\n");
+
+	unit = uvc_alloc_entity(UVC_EXT_GPIO_UNIT, UVC_EXT_GPIO_UNIT_ID, 0, 1);
+	if (!unit)
+		return -ENOMEM;
+
+	unit->gpio.gpio_privacy = gpio_privacy;
+	unit->gpio.irq = irq;
+	unit->gpio.bControlSize = 1;
+	unit->gpio.bmControls = (u8 *)unit + sizeof(*unit);
+	unit->gpio.bmControls[0] = 1;
+	unit->get_cur = uvc_gpio_get_cur;
+	unit->get_info = uvc_gpio_get_info;
+	strscpy(unit->name, "GPIO", sizeof(unit->name));
+
+	list_add_tail(&unit->list, &dev->entities);
+
+	dev->gpio_unit = unit;
+
+	return 0;
+}
+
+static int uvc_gpio_init_irq(struct uvc_device *dev)
+{
+	struct uvc_entity *unit = dev->gpio_unit;
+
+	if (!unit || unit->gpio.irq < 0)
+		return 0;
+
+	return devm_request_threaded_irq(&dev->udev->dev, unit->gpio.irq, NULL,
+					 uvc_gpio_irq,
+					 IRQF_ONESHOT | IRQF_TRIGGER_FALLING |
+					 IRQF_TRIGGER_RISING,
+					 "uvc_privacy_gpio", dev);
+}
+
+/* ------------------------------------------------------------------------
+ * UVC device scan
+ */
+
+/*
+ * Scan the UVC descriptors to locate a chain starting at an Output Terminal
+ * and containing the following units:
+ *
+ * - one or more Output Terminals (USB Streaming or Display)
+ * - zero or one Processing Unit
+ * - zero, one or more single-input Selector Units
+ * - zero or one multiple-input Selector Units, provided all inputs are
+ *   connected to input terminals
+ * - zero, one or mode single-input Extension Units
+ * - one or more Input Terminals (Camera, External or USB Streaming)
+ *
+ * The terminal and units must match on of the following structures:
+ *
+ * ITT_*(0) -> +---------+    +---------+    +---------+ -> TT_STREAMING(0)
+ * ...         | SU{0,1} | -> | PU{0,1} | -> | XU{0,n} |    ...
+ * ITT_*(n) -> +---------+    +---------+    +---------+ -> TT_STREAMING(n)
+ *
+ *                 +---------+    +---------+ -> OTT_*(0)
+ * TT_STREAMING -> | PU{0,1} | -> | XU{0,n} |    ...
+ *                 +---------+    +---------+ -> OTT_*(n)
+ *
+ * The Processing Unit and Extension Units can be in any order. Additional
+ * Extension Units connected to the main chain as single-unit branches are
+ * also supported. Single-input Selector Units are ignored.
+ */
+static int uvc_scan_chain_entity(struct uvc_video_chain *chain,
+	struct uvc_entity *entity)
+{
+	switch (UVC_ENTITY_TYPE(entity)) {
+	case UVC_VC_EXTENSION_UNIT:
+		uvc_dbg_cont(PROBE, " <- XU %d", entity->id);
+
+		if (entity->bNrInPins != 1) {
+			uvc_dbg(chain->dev, DESCR,
+				"Extension unit %d has more than 1 input pin\n",
+				entity->id);
+			return -1;
+		}
+
+		break;
+
+	case UVC_VC_PROCESSING_UNIT:
+		uvc_dbg_cont(PROBE, " <- PU %d", entity->id);
+
+		if (chain->processing != NULL) {
+			uvc_dbg(chain->dev, DESCR,
+				"Found multiple Processing Units in chain\n");
+			return -1;
+		}
+
+		chain->processing = entity;
+		break;
+
+	case UVC_VC_SELECTOR_UNIT:
+		uvc_dbg_cont(PROBE, " <- SU %d", entity->id);
+
+		/* Single-input selector units are ignored. */
+		if (entity->bNrInPins == 1)
+			break;
+
+		if (chain->selector != NULL) {
+			uvc_dbg(chain->dev, DESCR,
+				"Found multiple Selector Units in chain\n");
+			return -1;
+		}
+
+		chain->selector = entity;
+		break;
+
+	case UVC_ITT_VENDOR_SPECIFIC:
+	case UVC_ITT_CAMERA:
+	case UVC_ITT_MEDIA_TRANSPORT_INPUT:
+		uvc_dbg_cont(PROBE, " <- IT %d\n", entity->id);
+
+		break;
+
+	case UVC_OTT_VENDOR_SPECIFIC:
+	case UVC_OTT_DISPLAY:
+	case UVC_OTT_MEDIA_TRANSPORT_OUTPUT:
+		uvc_dbg_cont(PROBE, " OT %d", entity->id);
+
+		break;
+
+	case UVC_TT_STREAMING:
+		if (UVC_ENTITY_IS_ITERM(entity))
+			uvc_dbg_cont(PROBE, " <- IT %d\n", entity->id);
+		else
+			uvc_dbg_cont(PROBE, " OT %d", entity->id);
+
+		break;
+
+	default:
+		uvc_dbg(chain->dev, DESCR,
+			"Unsupported entity type 0x%04x found in chain\n",
+			UVC_ENTITY_TYPE(entity));
+		return -1;
+	}
+
+	list_add_tail(&entity->chain, &chain->entities);
+	return 0;
+}
+
+static int uvc_scan_chain_forward(struct uvc_video_chain *chain,
+	struct uvc_entity *entity, struct uvc_entity *prev)
+{
+	struct uvc_entity *forward;
+	int found;
+
+	/* Forward scan */
+	forward = NULL;
+	found = 0;
+
+	while (1) {
+		forward = uvc_entity_by_reference(chain->dev, entity->id,
+			forward);
+		if (forward == NULL)
+			break;
+		if (forward == prev)
+			continue;
+		if (forward->chain.next || forward->chain.prev) {
+			uvc_dbg(chain->dev, DESCR,
+				"Found reference to entity %d already in chain\n",
+				forward->id);
+			return -EINVAL;
+		}
+
+		switch (UVC_ENTITY_TYPE(forward)) {
+		case UVC_VC_EXTENSION_UNIT:
+			if (forward->bNrInPins != 1) {
+				uvc_dbg(chain->dev, DESCR,
+					"Extension unit %d has more than 1 input pin\n",
+					forward->id);
+				return -EINVAL;
+			}
+
+			/*
+			 * Some devices reference an output terminal as the
+			 * source of extension units. This is incorrect, as
+			 * output terminals only have an input pin, and thus
+			 * can't be connected to any entity in the forward
+			 * direction. The resulting topology would cause issues
+			 * when registering the media controller graph. To
+			 * avoid this problem, connect the extension unit to
+			 * the source of the output terminal instead.
+			 */
+			if (UVC_ENTITY_IS_OTERM(entity)) {
+				struct uvc_entity *source;
+
+				source = uvc_entity_by_id(chain->dev,
+							  entity->baSourceID[0]);
+				if (!source) {
+					uvc_dbg(chain->dev, DESCR,
+						"Can't connect extension unit %u in chain\n",
+						forward->id);
+					break;
+				}
+
+				forward->baSourceID[0] = source->id;
+			}
+
+			list_add_tail(&forward->chain, &chain->entities);
+			if (!found)
+				uvc_dbg_cont(PROBE, " (->");
+
+			uvc_dbg_cont(PROBE, " XU %d", forward->id);
+			found = 1;
+			break;
+
+		case UVC_OTT_VENDOR_SPECIFIC:
+		case UVC_OTT_DISPLAY:
+		case UVC_OTT_MEDIA_TRANSPORT_OUTPUT:
+		case UVC_TT_STREAMING:
+			if (UVC_ENTITY_IS_ITERM(forward)) {
+				uvc_dbg(chain->dev, DESCR,
+					"Unsupported input terminal %u\n",
+					forward->id);
+				return -EINVAL;
+			}
+
+			if (UVC_ENTITY_IS_OTERM(entity)) {
+				uvc_dbg(chain->dev, DESCR,
+					"Unsupported connection between output terminals %u and %u\n",
+					entity->id, forward->id);
+				break;
+			}
+
+			list_add_tail(&forward->chain, &chain->entities);
+			if (!found)
+				uvc_dbg_cont(PROBE, " (->");
+
+			uvc_dbg_cont(PROBE, " OT %d", forward->id);
+			found = 1;
+			break;
+		}
+	}
+	if (found)
+		uvc_dbg_cont(PROBE, ")");
+
+	return 0;
+}
+
+static int uvc_scan_chain_backward(struct uvc_video_chain *chain,
+	struct uvc_entity **_entity)
+{
+	struct uvc_entity *entity = *_entity;
+	struct uvc_entity *term;
+	int id = -EINVAL, i;
+
+	switch (UVC_ENTITY_TYPE(entity)) {
+	case UVC_VC_EXTENSION_UNIT:
+	case UVC_VC_PROCESSING_UNIT:
+		id = entity->baSourceID[0];
+		break;
+
+	case UVC_VC_SELECTOR_UNIT:
+		/* Single-input selector units are ignored. */
+		if (entity->bNrInPins == 1) {
+			id = entity->baSourceID[0];
+			break;
+		}
+
+		uvc_dbg_cont(PROBE, " <- IT");
+
+		chain->selector = entity;
+		for (i = 0; i < entity->bNrInPins; ++i) {
+			id = entity->baSourceID[i];
+			term = uvc_entity_by_id(chain->dev, id);
+			if (term == NULL || !UVC_ENTITY_IS_ITERM(term)) {
+				uvc_dbg(chain->dev, DESCR,
+					"Selector unit %d input %d isn't connected to an input terminal\n",
+					entity->id, i);
+				return -1;
+			}
+
+			if (term->chain.next || term->chain.prev) {
+				uvc_dbg(chain->dev, DESCR,
+					"Found reference to entity %d already in chain\n",
+					term->id);
+				return -EINVAL;
+			}
+
+			uvc_dbg_cont(PROBE, " %d", term->id);
+
+			list_add_tail(&term->chain, &chain->entities);
+			uvc_scan_chain_forward(chain, term, entity);
+		}
+
+		uvc_dbg_cont(PROBE, "\n");
+
+		id = 0;
+		break;
+
+	case UVC_ITT_VENDOR_SPECIFIC:
+	case UVC_ITT_CAMERA:
+	case UVC_ITT_MEDIA_TRANSPORT_INPUT:
+	case UVC_OTT_VENDOR_SPECIFIC:
+	case UVC_OTT_DISPLAY:
+	case UVC_OTT_MEDIA_TRANSPORT_OUTPUT:
+	case UVC_TT_STREAMING:
+		id = UVC_ENTITY_IS_OTERM(entity) ? entity->baSourceID[0] : 0;
+		break;
+	}
+
+	if (id <= 0) {
+		*_entity = NULL;
+		return id;
+	}
+
+	entity = uvc_entity_by_id(chain->dev, id);
+	if (entity == NULL) {
+		uvc_dbg(chain->dev, DESCR,
+			"Found reference to unknown entity %d\n", id);
+		return -EINVAL;
+	}
+
+	*_entity = entity;
+	return 0;
+}
+
+static int uvc_scan_chain(struct uvc_video_chain *chain,
+			  struct uvc_entity *term)
+{
+	struct uvc_entity *entity, *prev;
+
+	uvc_dbg(chain->dev, PROBE, "Scanning UVC chain:");
+
+	entity = term;
+	prev = NULL;
+
+	while (entity != NULL) {
+		/* Entity must not be part of an existing chain */
+		if (entity->chain.next || entity->chain.prev) {
+			uvc_dbg(chain->dev, DESCR,
+				"Found reference to entity %d already in chain\n",
+				entity->id);
+			return -EINVAL;
+		}
+
+		/* Process entity */
+		if (uvc_scan_chain_entity(chain, entity) < 0)
+			return -EINVAL;
+
+		/* Forward scan */
+		if (uvc_scan_chain_forward(chain, entity, prev) < 0)
+			return -EINVAL;
+
+		/* Backward scan */
+		prev = entity;
+		if (uvc_scan_chain_backward(chain, &entity) < 0)
+			return -EINVAL;
+	}
+
+	return 0;
+}
+
+static unsigned int uvc_print_terms(struct list_head *terms, u16 dir,
+		char *buffer)
+{
+	struct uvc_entity *term;
+	unsigned int nterms = 0;
+	char *p = buffer;
+
+	list_for_each_entry(term, terms, chain) {
+		if (!UVC_ENTITY_IS_TERM(term) ||
+		    UVC_TERM_DIRECTION(term) != dir)
+			continue;
+
+		if (nterms)
+			p += sprintf(p, ",");
+		if (++nterms >= 4) {
+			p += sprintf(p, "...");
+			break;
+		}
+		p += sprintf(p, "%u", term->id);
+	}
+
+	return p - buffer;
+}
+
+static const char *uvc_print_chain(struct uvc_video_chain *chain)
+{
+	static char buffer[43];
+	char *p = buffer;
+
+	p += uvc_print_terms(&chain->entities, UVC_TERM_INPUT, p);
+	p += sprintf(p, " -> ");
+	uvc_print_terms(&chain->entities, UVC_TERM_OUTPUT, p);
+
+	return buffer;
+}
+
+static struct uvc_video_chain *uvc_alloc_chain(struct uvc_device *dev)
+{
+	struct uvc_video_chain *chain;
+
+	chain = kzalloc(sizeof(*chain), GFP_KERNEL);
+	if (chain == NULL)
+		return NULL;
+
+	INIT_LIST_HEAD(&chain->entities);
+	mutex_init(&chain->ctrl_mutex);
+	chain->dev = dev;
+	v4l2_prio_init(&chain->prio);
+
+	return chain;
+}
+
+/*
+ * Fallback heuristic for devices that don't connect units and terminals in a
+ * valid chain.
+ *
+ * Some devices have invalid baSourceID references, causing uvc_scan_chain()
+ * to fail, but if we just take the entities we can find and put them together
+ * in the most sensible chain we can think of, turns out they do work anyway.
+ * Note: This heuristic assumes there is a single chain.
+ *
+ * At the time of writing, devices known to have such a broken chain are
+ *  - Acer Integrated Camera (5986:055a)
+ *  - Realtek rtl157a7 (0bda:57a7)
+ */
+static int uvc_scan_fallback(struct uvc_device *dev)
+{
+	struct uvc_video_chain *chain;
+	struct uvc_entity *iterm = NULL;
+	struct uvc_entity *oterm = NULL;
+	struct uvc_entity *entity;
+	struct uvc_entity *prev;
+
+	/*
+	 * Start by locating the input and output terminals. We only support
+	 * devices with exactly one of each for now.
+	 */
+	list_for_each_entry(entity, &dev->entities, list) {
+		if (UVC_ENTITY_IS_ITERM(entity)) {
+			if (iterm)
+				return -EINVAL;
+			iterm = entity;
+		}
+
+		if (UVC_ENTITY_IS_OTERM(entity)) {
+			if (oterm)
+				return -EINVAL;
+			oterm = entity;
+		}
+	}
+
+	if (iterm == NULL || oterm == NULL)
+		return -EINVAL;
+
+	/* Allocate the chain and fill it. */
+	chain = uvc_alloc_chain(dev);
+	if (chain == NULL)
+		return -ENOMEM;
+
+	if (uvc_scan_chain_entity(chain, oterm) < 0)
+		goto error;
+
+	prev = oterm;
+
+	/*
+	 * Add all Processing and Extension Units with two pads. The order
+	 * doesn't matter much, use reverse list traversal to connect units in
+	 * UVC descriptor order as we build the chain from output to input. This
+	 * leads to units appearing in the order meant by the manufacturer for
+	 * the cameras known to require this heuristic.
+	 */
+	list_for_each_entry_reverse(entity, &dev->entities, list) {
+		if (entity->type != UVC_VC_PROCESSING_UNIT &&
+		    entity->type != UVC_VC_EXTENSION_UNIT)
+			continue;
+
+		if (entity->num_pads != 2)
+			continue;
+
+		if (uvc_scan_chain_entity(chain, entity) < 0)
+			goto error;
+
+		prev->baSourceID[0] = entity->id;
+		prev = entity;
+	}
+
+	if (uvc_scan_chain_entity(chain, iterm) < 0)
+		goto error;
+
+	prev->baSourceID[0] = iterm->id;
+
+	list_add_tail(&chain->list, &dev->chains);
+
+	uvc_dbg(dev, PROBE, "Found a video chain by fallback heuristic (%s)\n",
+		uvc_print_chain(chain));
+
+	return 0;
+
+error:
+	kfree(chain);
+	return -EINVAL;
+}
+
+/*
+ * Scan the device for video chains and register video devices.
+ *
+ * Chains are scanned starting at their output terminals and walked backwards.
+ */
+static int uvc_scan_device(struct uvc_device *dev)
+{
+	struct uvc_video_chain *chain;
+	struct uvc_entity *term;
+
+	list_for_each_entry(term, &dev->entities, list) {
+		if (!UVC_ENTITY_IS_OTERM(term))
+			continue;
+
+		/*
+		 * If the terminal is already included in a chain, skip it.
+		 * This can happen for chains that have multiple output
+		 * terminals, where all output terminals beside the first one
+		 * will be inserted in the chain in forward scans.
+		 */
+		if (term->chain.next || term->chain.prev)
+			continue;
+
+		chain = uvc_alloc_chain(dev);
+		if (chain == NULL)
+			return -ENOMEM;
+
+		term->flags |= UVC_ENTITY_FLAG_DEFAULT;
+
+		if (uvc_scan_chain(chain, term) < 0) {
+			kfree(chain);
+			continue;
+		}
+
+		uvc_dbg(dev, PROBE, "Found a valid video chain (%s)\n",
+			uvc_print_chain(chain));
+
+		list_add_tail(&chain->list, &dev->chains);
+	}
+
+	if (list_empty(&dev->chains))
+		uvc_scan_fallback(dev);
+
+	if (list_empty(&dev->chains)) {
+		dev_info(&dev->udev->dev, "No valid video chain found.\n");
+		return -1;
+	}
+
+	/* Add GPIO entity to the first chain. */
+	if (dev->gpio_unit) {
+		chain = list_first_entry(&dev->chains,
+					 struct uvc_video_chain, list);
+		list_add_tail(&dev->gpio_unit->chain, &chain->entities);
+	}
+
+	return 0;
+}
+
+/* ------------------------------------------------------------------------
+ * Video device registration and unregistration
+ */
+
+/*
+ * Delete the UVC device.
+ *
+ * Called by the kernel when the last reference to the uvc_device structure
+ * is released.
+ *
+ * As this function is called after or during disconnect(), all URBs have
+ * already been cancelled by the USB core. There is no need to kill the
+ * interrupt URB manually.
+ */
+static void uvc_delete(struct kref *kref)
+{
+	struct uvc_device *dev = container_of(kref, struct uvc_device, ref);
+	struct list_head *p, *n;
+
+	uvc_status_cleanup(dev);
+	uvc_ctrl_cleanup_device(dev);
+
+	usb_put_intf(dev->intf);
+	usb_put_dev(dev->udev);
+
+#ifdef CONFIG_MEDIA_CONTROLLER
+	media_device_cleanup(&dev->mdev);
+#endif
+
+	list_for_each_safe(p, n, &dev->chains) {
+		struct uvc_video_chain *chain;
+
+		chain = list_entry(p, struct uvc_video_chain, list);
+		kfree(chain);
+	}
+
+	list_for_each_safe(p, n, &dev->entities) {
+		struct uvc_entity *entity;
+
+		entity = list_entry(p, struct uvc_entity, list);
+#ifdef CONFIG_MEDIA_CONTROLLER
+		uvc_mc_cleanup_entity(entity);
+#endif
+		kfree(entity);
+	}
+
+	list_for_each_safe(p, n, &dev->streams) {
+		struct uvc_streaming *streaming;
+
+		streaming = list_entry(p, struct uvc_streaming, list);
+		usb_driver_release_interface(&uvc_driver.driver,
+			streaming->intf);
+		uvc_stream_delete(streaming);
+	}
+
+	kfree(dev);
+}
+
+static void uvc_release(struct video_device *vdev)
+{
+	struct uvc_streaming *stream = video_get_drvdata(vdev);
+	struct uvc_device *dev = stream->dev;
+
+	kref_put(&dev->ref, uvc_delete);
+}
+
+/*
+ * Unregister the video devices.
+ */
+static void uvc_unregister_video(struct uvc_device *dev)
+{
+	struct uvc_streaming *stream;
+
+	list_for_each_entry(stream, &dev->streams, list) {
+		if (!video_is_registered(&stream->vdev))
+			continue;
+
+		video_unregister_device(&stream->vdev);
+		video_unregister_device(&stream->meta.vdev);
+
+		uvc_debugfs_cleanup_stream(stream);
+	}
+
+	uvc_status_unregister(dev);
+
+	if (dev->vdev.dev)
+		v4l2_device_unregister(&dev->vdev);
+#ifdef CONFIG_MEDIA_CONTROLLER
+	if (media_devnode_is_registered(dev->mdev.devnode))
+		media_device_unregister(&dev->mdev);
+#endif
+}
+
+int uvc_register_video_device(struct uvc_device *dev,
+			      struct uvc_streaming *stream,
+			      struct video_device *vdev,
+			      struct uvc_video_queue *queue,
+			      enum v4l2_buf_type type,
+			      const struct v4l2_file_operations *fops,
+			      const struct v4l2_ioctl_ops *ioctl_ops)
+{
+	int ret;
+
+	/* Initialize the video buffers queue. */
+	ret = uvc_queue_init(queue, type, !uvc_no_drop_param);
+	if (ret)
+		return ret;
+
+	/* Register the device with V4L. */
+
+	/*
+	 * We already hold a reference to dev->udev. The video device will be
+	 * unregistered before the reference is released, so we don't need to
+	 * get another one.
+	 */
+	vdev->v4l2_dev = &dev->vdev;
+	vdev->fops = fops;
+	vdev->ioctl_ops = ioctl_ops;
+	vdev->release = uvc_release;
+	vdev->prio = &stream->chain->prio;
+	if (type == V4L2_BUF_TYPE_VIDEO_OUTPUT)
+		vdev->vfl_dir = VFL_DIR_TX;
+	else
+		vdev->vfl_dir = VFL_DIR_RX;
+
+	switch (type) {
+	case V4L2_BUF_TYPE_VIDEO_CAPTURE:
+	default:
+		vdev->device_caps = V4L2_CAP_VIDEO_CAPTURE | V4L2_CAP_STREAMING;
+		break;
+	case V4L2_BUF_TYPE_VIDEO_OUTPUT:
+		vdev->device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
+		break;
+	case V4L2_BUF_TYPE_META_CAPTURE:
+		vdev->device_caps = V4L2_CAP_META_CAPTURE | V4L2_CAP_STREAMING;
+		break;
+	}
+
+	strscpy(vdev->name, dev->name, sizeof(vdev->name));
+
+	/*
+	 * Set the driver data before calling video_register_device, otherwise
+	 * the file open() handler might race us.
+	 */
+	video_set_drvdata(vdev, stream);
+
+	ret = video_register_device(vdev, VFL_TYPE_VIDEO, -1);
+	if (ret < 0) {
+		dev_err(&stream->intf->dev,
+			"Failed to register %s device (%d).\n",
+			v4l2_type_names[type], ret);
+		return ret;
+	}
+
+	kref_get(&dev->ref);
+	return 0;
+}
+
+static int uvc_register_video(struct uvc_device *dev,
+		struct uvc_streaming *stream)
+{
+	int ret;
+
+	/* Initialize the streaming interface with default parameters. */
+	ret = uvc_video_init(stream);
+	if (ret < 0) {
+		dev_err(&stream->intf->dev,
+			"Failed to initialize the device (%d).\n", ret);
+		return ret;
+	}
+
+	if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
+		stream->chain->caps |= V4L2_CAP_VIDEO_CAPTURE
+			| V4L2_CAP_META_CAPTURE;
+	else
+		stream->chain->caps |= V4L2_CAP_VIDEO_OUTPUT;
+
+	uvc_debugfs_init_stream(stream);
+
+	/* Register the device with V4L. */
+	return uvc_register_video_device(dev, stream, &stream->vdev,
+					 &stream->queue, stream->type,
+					 &uvc_fops, &uvc_ioctl_ops);
+}
+
+/*
+ * Register all video devices in all chains.
+ */
+static int uvc_register_terms(struct uvc_device *dev,
+	struct uvc_video_chain *chain)
+{
+	struct uvc_streaming *stream;
+	struct uvc_entity *term;
+	int ret;
+
+	list_for_each_entry(term, &chain->entities, chain) {
+		if (UVC_ENTITY_TYPE(term) != UVC_TT_STREAMING)
+			continue;
+
+		stream = uvc_stream_by_id(dev, term->id);
+		if (stream == NULL) {
+			dev_info(&dev->udev->dev,
+				 "No streaming interface found for terminal %u.",
+				 term->id);
+			continue;
+		}
+
+		stream->chain = chain;
+		ret = uvc_register_video(dev, stream);
+		if (ret < 0)
+			return ret;
+
+		/*
+		 * Register a metadata node, but ignore a possible failure,
+		 * complete registration of video nodes anyway.
+		 */
+		uvc_meta_register(stream);
+
+		term->vdev = &stream->vdev;
+	}
+
+	return 0;
+}
+
+static int uvc_register_chains(struct uvc_device *dev)
+{
+	struct uvc_video_chain *chain;
+	int ret;
+
+	list_for_each_entry(chain, &dev->chains, list) {
+		ret = uvc_register_terms(dev, chain);
+		if (ret < 0)
+			return ret;
+
+#ifdef CONFIG_MEDIA_CONTROLLER
+		ret = uvc_mc_register_entities(chain);
+		if (ret < 0)
+			dev_info(&dev->udev->dev,
+				 "Failed to register entities (%d).\n", ret);
+#endif
+	}
+
+	return 0;
+}
+
+/* ------------------------------------------------------------------------
+ * USB probe, disconnect, suspend and resume
+ */
+
+static const struct uvc_device_info uvc_quirk_none = { 0 };
+
+static int uvc_probe(struct usb_interface *intf,
+		     const struct usb_device_id *id)
+{
+	struct usb_device *udev = interface_to_usbdev(intf);
+	struct uvc_device *dev;
+	const struct uvc_device_info *info =
+		(const struct uvc_device_info *)id->driver_info;
+	int function;
+	int ret;
+
+	/* Allocate memory for the device and initialize it. */
+	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+	if (dev == NULL)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&dev->entities);
+	INIT_LIST_HEAD(&dev->chains);
+	INIT_LIST_HEAD(&dev->streams);
+	kref_init(&dev->ref);
+	atomic_set(&dev->nmappings, 0);
+	mutex_init(&dev->lock);
+
+	dev->udev = usb_get_dev(udev);
+	dev->intf = usb_get_intf(intf);
+	dev->intfnum = intf->cur_altsetting->desc.bInterfaceNumber;
+	dev->info = info ? info : &uvc_quirk_none;
+	dev->quirks = uvc_quirks_param == -1
+		    ? dev->info->quirks : uvc_quirks_param;
+
+	if (id->idVendor && id->idProduct)
+		uvc_dbg(dev, PROBE, "Probing known UVC device %s (%04x:%04x)\n",
+			udev->devpath, id->idVendor, id->idProduct);
+	else
+		uvc_dbg(dev, PROBE, "Probing generic UVC device %s\n",
+			udev->devpath);
+
+	if (udev->product != NULL)
+		strscpy(dev->name, udev->product, sizeof(dev->name));
+	else
+		snprintf(dev->name, sizeof(dev->name),
+			 "UVC Camera (%04x:%04x)",
+			 le16_to_cpu(udev->descriptor.idVendor),
+			 le16_to_cpu(udev->descriptor.idProduct));
+
+	/*
+	 * Add iFunction or iInterface to names when available as additional
+	 * distinguishers between interfaces. iFunction is prioritized over
+	 * iInterface which matches Windows behavior at the point of writing.
+	 */
+	if (intf->intf_assoc && intf->intf_assoc->iFunction != 0)
+		function = intf->intf_assoc->iFunction;
+	else
+		function = intf->cur_altsetting->desc.iInterface;
+	if (function != 0) {
+		size_t len;
+
+		strlcat(dev->name, ": ", sizeof(dev->name));
+		len = strlen(dev->name);
+		usb_string(udev, function, dev->name + len,
+			   sizeof(dev->name) - len);
+	}
+
+	/* Initialize the media device. */
+#ifdef CONFIG_MEDIA_CONTROLLER
+	dev->mdev.dev = &intf->dev;
+	strscpy(dev->mdev.model, dev->name, sizeof(dev->mdev.model));
+	if (udev->serial)
+		strscpy(dev->mdev.serial, udev->serial,
+			sizeof(dev->mdev.serial));
+	usb_make_path(udev, dev->mdev.bus_info, sizeof(dev->mdev.bus_info));
+	dev->mdev.hw_revision = le16_to_cpu(udev->descriptor.bcdDevice);
+	media_device_init(&dev->mdev);
+
+	dev->vdev.mdev = &dev->mdev;
+#endif
+
+	/* Parse the Video Class control descriptor. */
+	if (uvc_parse_control(dev) < 0) {
+		uvc_dbg(dev, PROBE, "Unable to parse UVC descriptors\n");
+		goto error;
+	}
+
+	/* Parse the associated GPIOs. */
+	if (uvc_gpio_parse(dev) < 0) {
+		uvc_dbg(dev, PROBE, "Unable to parse UVC GPIOs\n");
+		goto error;
+	}
+
+	dev_info(&dev->udev->dev, "Found UVC %u.%02x device %s (%04x:%04x)\n",
+		 dev->uvc_version >> 8, dev->uvc_version & 0xff,
+		 udev->product ? udev->product : "<unnamed>",
+		 le16_to_cpu(udev->descriptor.idVendor),
+		 le16_to_cpu(udev->descriptor.idProduct));
+
+	if (dev->quirks != dev->info->quirks) {
+		dev_info(&dev->udev->dev,
+			 "Forcing device quirks to 0x%x by module parameter for testing purpose.\n",
+			 dev->quirks);
+		dev_info(&dev->udev->dev,
+			 "Please report required quirks to the linux-media mailing list.\n");
+	}
+
+	if (dev->info->uvc_version) {
+		dev->uvc_version = dev->info->uvc_version;
+		dev_info(&dev->udev->dev, "Forcing UVC version to %u.%02x\n",
+			 dev->uvc_version >> 8, dev->uvc_version & 0xff);
+	}
+
+	/* Register the V4L2 device. */
+	if (v4l2_device_register(&intf->dev, &dev->vdev) < 0)
+		goto error;
+
+	/* Scan the device for video chains. */
+	if (uvc_scan_device(dev) < 0)
+		goto error;
+
+	/* Initialize controls. */
+	if (uvc_ctrl_init_device(dev) < 0)
+		goto error;
+
+	/* Register video device nodes. */
+	if (uvc_register_chains(dev) < 0)
+		goto error;
+
+#ifdef CONFIG_MEDIA_CONTROLLER
+	/* Register the media device node */
+	if (media_device_register(&dev->mdev) < 0)
+		goto error;
+#endif
+	/* Save our data pointer in the interface data. */
+	usb_set_intfdata(intf, dev);
+
+	/* Initialize the interrupt URB. */
+	ret = uvc_status_init(dev);
+	if (ret < 0) {
+		dev_info(&dev->udev->dev,
+			 "Unable to initialize the status endpoint (%d), status interrupt will not be supported.\n",
+			 ret);
+	}
+
+	ret = uvc_gpio_init_irq(dev);
+	if (ret < 0) {
+		dev_err(&dev->udev->dev,
+			"Unable to request privacy GPIO IRQ (%d)\n", ret);
+		goto error;
+	}
+
+	uvc_dbg(dev, PROBE, "UVC device initialized\n");
+	usb_enable_autosuspend(udev);
+	return 0;
+
+error:
+	uvc_unregister_video(dev);
+	kref_put(&dev->ref, uvc_delete);
+	return -ENODEV;
+}
+
+static void uvc_disconnect(struct usb_interface *intf)
+{
+	struct uvc_device *dev = usb_get_intfdata(intf);
+
+	/*
+	 * Set the USB interface data to NULL. This can be done outside the
+	 * lock, as there's no other reader.
+	 */
+	usb_set_intfdata(intf, NULL);
+
+	if (intf->cur_altsetting->desc.bInterfaceSubClass ==
+	    UVC_SC_VIDEOSTREAMING)
+		return;
+
+	uvc_unregister_video(dev);
+	kref_put(&dev->ref, uvc_delete);
+}
+
+static int uvc_suspend(struct usb_interface *intf, pm_message_t message)
+{
+	struct uvc_device *dev = usb_get_intfdata(intf);
+	struct uvc_streaming *stream;
+
+	uvc_dbg(dev, SUSPEND, "Suspending interface %u\n",
+		intf->cur_altsetting->desc.bInterfaceNumber);
+
+	/* Controls are cached on the fly so they don't need to be saved. */
+	if (intf->cur_altsetting->desc.bInterfaceSubClass ==
+	    UVC_SC_VIDEOCONTROL) {
+		mutex_lock(&dev->lock);
+		if (dev->users)
+			uvc_status_stop(dev);
+		mutex_unlock(&dev->lock);
+		return 0;
+	}
+
+	list_for_each_entry(stream, &dev->streams, list) {
+		if (stream->intf == intf)
+			return uvc_video_suspend(stream);
+	}
+
+	uvc_dbg(dev, SUSPEND,
+		"Suspend: video streaming USB interface mismatch\n");
+	return -EINVAL;
+}
+
+static int __uvc_resume(struct usb_interface *intf, int reset)
+{
+	struct uvc_device *dev = usb_get_intfdata(intf);
+	struct uvc_streaming *stream;
+	int ret = 0;
+
+	uvc_dbg(dev, SUSPEND, "Resuming interface %u\n",
+		intf->cur_altsetting->desc.bInterfaceNumber);
+
+	if (intf->cur_altsetting->desc.bInterfaceSubClass ==
+	    UVC_SC_VIDEOCONTROL) {
+		if (reset) {
+			ret = uvc_ctrl_restore_values(dev);
+			if (ret < 0)
+				return ret;
+		}
+
+		mutex_lock(&dev->lock);
+		if (dev->users)
+			ret = uvc_status_start(dev, GFP_NOIO);
+		mutex_unlock(&dev->lock);
+
+		return ret;
+	}
+
+	list_for_each_entry(stream, &dev->streams, list) {
+		if (stream->intf == intf) {
+			ret = uvc_video_resume(stream, reset);
+			if (ret < 0)
+				uvc_queue_streamoff(&stream->queue,
+						    stream->queue.queue.type);
+			return ret;
+		}
+	}
+
+	uvc_dbg(dev, SUSPEND,
+		"Resume: video streaming USB interface mismatch\n");
+	return -EINVAL;
+}
+
+static int uvc_resume(struct usb_interface *intf)
+{
+	return __uvc_resume(intf, 0);
+}
+
+static int uvc_reset_resume(struct usb_interface *intf)
+{
+	return __uvc_resume(intf, 1);
+}
+
+/* ------------------------------------------------------------------------
+ * Module parameters
+ */
+
+static int uvc_clock_param_get(char *buffer, const struct kernel_param *kp)
+{
+	if (uvc_clock_param == CLOCK_MONOTONIC)
+		return sprintf(buffer, "CLOCK_MONOTONIC");
+	else
+		return sprintf(buffer, "CLOCK_REALTIME");
+}
+
+static int uvc_clock_param_set(const char *val, const struct kernel_param *kp)
+{
+	if (strncasecmp(val, "clock_", strlen("clock_")) == 0)
+		val += strlen("clock_");
+
+	if (strcasecmp(val, "monotonic") == 0)
+		uvc_clock_param = CLOCK_MONOTONIC;
+	else if (strcasecmp(val, "realtime") == 0)
+		uvc_clock_param = CLOCK_REALTIME;
+	else
+		return -EINVAL;
+
+	return 0;
+}
+
+module_param_call(clock, uvc_clock_param_set, uvc_clock_param_get,
+		  &uvc_clock_param, 0644);
+MODULE_PARM_DESC(clock, "Video buffers timestamp clock");
+module_param_named(hwtimestamps, uvc_hw_timestamps_param, uint, 0644);
+MODULE_PARM_DESC(hwtimestamps, "Use hardware timestamps");
+module_param_named(nodrop, uvc_no_drop_param, uint, 0644);
+MODULE_PARM_DESC(nodrop, "Don't drop incomplete frames");
+module_param_named(quirks, uvc_quirks_param, uint, 0644);
+MODULE_PARM_DESC(quirks, "Forced device quirks");
+module_param_named(trace, uvc_dbg_param, uint, 0644);
+MODULE_PARM_DESC(trace, "Trace level bitmask");
+module_param_named(timeout, uvc_timeout_param, uint, 0644);
+MODULE_PARM_DESC(timeout, "Streaming control requests timeout");
+
+/* ------------------------------------------------------------------------
+ * Driver initialization and cleanup
+ */
+
+static const struct uvc_device_info uvc_ctrl_power_line_limited = {
+	.mappings = (const struct uvc_control_mapping *[]) {
+		&uvc_ctrl_power_line_mapping_limited,
+		NULL, /* Sentinel */
+	},
+};
+
+static const struct uvc_device_info uvc_ctrl_power_line_uvc11 = {
+	.mappings = (const struct uvc_control_mapping *[]) {
+		&uvc_ctrl_power_line_mapping_uvc11,
+		NULL, /* Sentinel */
+	},
+};
+
+static const struct uvc_device_info uvc_quirk_probe_minmax = {
+	.quirks = UVC_QUIRK_PROBE_MINMAX,
+};
+
+static const struct uvc_device_info uvc_quirk_fix_bandwidth = {
+	.quirks = UVC_QUIRK_FIX_BANDWIDTH,
+};
+
+static const struct uvc_device_info uvc_quirk_probe_def = {
+	.quirks = UVC_QUIRK_PROBE_DEF,
+};
+
+static const struct uvc_device_info uvc_quirk_stream_no_fid = {
+	.quirks = UVC_QUIRK_STREAM_NO_FID,
+};
+
+static const struct uvc_device_info uvc_quirk_force_y8 = {
+	.quirks = UVC_QUIRK_FORCE_Y8,
+};
+
+#define UVC_INFO_QUIRK(q) (kernel_ulong_t)&(struct uvc_device_info){.quirks = q}
+#define UVC_INFO_META(m) (kernel_ulong_t)&(struct uvc_device_info) \
+	{.meta_format = m}
+
+/*
+ * The Logitech cameras listed below have their interface class set to
+ * VENDOR_SPEC because they don't announce themselves as UVC devices, even
+ * though they are compliant.
+ */
+static const struct usb_device_id uvc_ids[] = {
+	/* Quanta USB2.0 HD UVC Webcam */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x0408,
+	  .idProduct		= 0x3090,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_ctrl_power_line_limited },
+	/* Quanta USB2.0 HD UVC Webcam */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x0408,
+	  .idProduct		= 0x4030,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_ctrl_power_line_limited },
+	/* Quanta USB2.0 HD UVC Webcam */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x0408,
+	  .idProduct		= 0x4034,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= UVC_PC_PROTOCOL_15,
+	  .driver_info		= (kernel_ulong_t)&uvc_ctrl_power_line_limited },
+	/* LogiLink Wireless Webcam */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x0416,
+	  .idProduct		= 0xa91a,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_minmax },
+	/* Genius eFace 2025 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x0458,
+	  .idProduct		= 0x706e,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_minmax },
+	/* Microsoft Lifecam NX-6000 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x045e,
+	  .idProduct		= 0x00f8,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_minmax },
+	/* Microsoft Lifecam NX-3000 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x045e,
+	  .idProduct		= 0x0721,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_def },
+	/* Microsoft Lifecam VX-7000 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x045e,
+	  .idProduct		= 0x0723,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_minmax },
+	/* Logitech, Webcam C910 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x046d,
+	  .idProduct		= 0x0821,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_QUIRK(UVC_QUIRK_WAKE_AUTOSUSPEND)},
+	/* Logitech, Webcam B910 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x046d,
+	  .idProduct		= 0x0823,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_QUIRK(UVC_QUIRK_WAKE_AUTOSUSPEND)},
+	/* Logitech Quickcam Fusion */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x046d,
+	  .idProduct		= 0x08c1,
+	  .bInterfaceClass	= USB_CLASS_VENDOR_SPEC,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0 },
+	/* Logitech Quickcam Orbit MP */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x046d,
+	  .idProduct		= 0x08c2,
+	  .bInterfaceClass	= USB_CLASS_VENDOR_SPEC,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0 },
+	/* Logitech Quickcam Pro for Notebook */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x046d,
+	  .idProduct		= 0x08c3,
+	  .bInterfaceClass	= USB_CLASS_VENDOR_SPEC,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0 },
+	/* Logitech Quickcam Pro 5000 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x046d,
+	  .idProduct		= 0x08c5,
+	  .bInterfaceClass	= USB_CLASS_VENDOR_SPEC,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0 },
+	/* Logitech Quickcam OEM Dell Notebook */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x046d,
+	  .idProduct		= 0x08c6,
+	  .bInterfaceClass	= USB_CLASS_VENDOR_SPEC,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0 },
+	/* Logitech Quickcam OEM Cisco VT Camera II */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x046d,
+	  .idProduct		= 0x08c7,
+	  .bInterfaceClass	= USB_CLASS_VENDOR_SPEC,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0 },
+	/* Logitech HD Pro Webcam C920 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x046d,
+	  .idProduct		= 0x082d,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_QUIRK(UVC_QUIRK_RESTORE_CTRLS_ON_INIT) },
+	/* Chicony CNF7129 (Asus EEE 100HE) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x04f2,
+	  .idProduct		= 0xb071,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_QUIRK(UVC_QUIRK_RESTRICT_FRAME_RATE) },
+	/* Chicony EasyCamera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x04f2,
+	  .idProduct		= 0xb5eb,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_ctrl_power_line_limited },
+	/* Chicony EasyCamera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x04f2,
+	  .idProduct		= 0xb6ba,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_ctrl_power_line_limited },
+	/* Chicony EasyCamera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x04f2,
+	  .idProduct		= 0xb746,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_ctrl_power_line_limited },
+	/* Alcor Micro AU3820 (Future Boy PC USB Webcam) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x058f,
+	  .idProduct		= 0x3820,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_minmax },
+	/* Dell XPS m1530 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x05a9,
+	  .idProduct		= 0x2640,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_def },
+	/* Dell SP2008WFP Monitor */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x05a9,
+	  .idProduct		= 0x2641,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_def },
+	/* Dell Alienware X51 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x05a9,
+	  .idProduct		= 0x2643,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_def },
+	/* Dell Studio Hybrid 140g (OmniVision webcam) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x05a9,
+	  .idProduct		= 0x264a,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_def },
+	/* Dell XPS M1330 (OmniVision OV7670 webcam) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x05a9,
+	  .idProduct		= 0x7670,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_def },
+	/* Apple Built-In iSight */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x05ac,
+	  .idProduct		= 0x8501,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_QUIRK(UVC_QUIRK_PROBE_MINMAX
+					| UVC_QUIRK_BUILTIN_ISIGHT) },
+	/* Apple FaceTime HD Camera (Built-In) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x05ac,
+	  .idProduct		= 0x8514,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_def },
+	/* Apple Built-In iSight via iBridge */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x05ac,
+	  .idProduct		= 0x8600,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_def },
+	/* Foxlink ("HP Webcam" on HP Mini 5103) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x05c8,
+	  .idProduct		= 0x0403,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_fix_bandwidth },
+	/* Genesys Logic USB 2.0 PC Camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x05e3,
+	  .idProduct		= 0x0505,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_stream_no_fid },
+	/* Hercules Classic Silver */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x06f8,
+	  .idProduct		= 0x300c,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_fix_bandwidth },
+	/* ViMicro Vega */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x0ac8,
+	  .idProduct		= 0x332d,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_fix_bandwidth },
+	/* ViMicro - Minoru3D */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x0ac8,
+	  .idProduct		= 0x3410,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_fix_bandwidth },
+	/* ViMicro Venus - Minoru3D */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x0ac8,
+	  .idProduct		= 0x3420,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_fix_bandwidth },
+	/* Ophir Optronics - SPCAM 620U */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x0bd3,
+	  .idProduct		= 0x0555,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_minmax },
+	/* MT6227 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x0e8d,
+	  .idProduct		= 0x0004,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_QUIRK(UVC_QUIRK_PROBE_MINMAX
+					| UVC_QUIRK_PROBE_DEF) },
+	/* IMC Networks (Medion Akoya) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x13d3,
+	  .idProduct		= 0x5103,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_stream_no_fid },
+	/* JMicron USB2.0 XGA WebCam */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x152d,
+	  .idProduct		= 0x0310,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_minmax },
+	/* Syntek (HP Spartan) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x174f,
+	  .idProduct		= 0x5212,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_stream_no_fid },
+	/* Syntek (Samsung Q310) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x174f,
+	  .idProduct		= 0x5931,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_stream_no_fid },
+	/* Syntek (Packard Bell EasyNote MX52 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x174f,
+	  .idProduct		= 0x8a12,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_stream_no_fid },
+	/* Syntek (Asus F9SG) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x174f,
+	  .idProduct		= 0x8a31,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_stream_no_fid },
+	/* Syntek (Asus U3S) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x174f,
+	  .idProduct		= 0x8a33,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_stream_no_fid },
+	/* Syntek (JAOtech Smart Terminal) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x174f,
+	  .idProduct		= 0x8a34,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_stream_no_fid },
+	/* Miricle 307K */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x17dc,
+	  .idProduct		= 0x0202,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_stream_no_fid },
+	/* Lenovo Thinkpad SL400/SL500 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x17ef,
+	  .idProduct		= 0x480b,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_stream_no_fid },
+	/* Aveo Technology USB 2.0 Camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x1871,
+	  .idProduct		= 0x0306,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_QUIRK(UVC_QUIRK_PROBE_MINMAX
+					| UVC_QUIRK_PROBE_EXTRAFIELDS) },
+	/* Aveo Technology USB 2.0 Camera (Tasco USB Microscope) */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x1871,
+	  .idProduct		= 0x0516,
+	  .bInterfaceClass	= USB_CLASS_VENDOR_SPEC,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0 },
+	/* Ecamm Pico iMage */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x18cd,
+	  .idProduct		= 0xcafe,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_QUIRK(UVC_QUIRK_PROBE_EXTRAFIELDS) },
+	/* Manta MM-353 Plako */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x18ec,
+	  .idProduct		= 0x3188,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_minmax },
+	/* FSC WebCam V30S */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x18ec,
+	  .idProduct		= 0x3288,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_minmax },
+	/* Arkmicro unbranded */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x18ec,
+	  .idProduct		= 0x3290,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_def },
+	/* The Imaging Source USB CCD cameras */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x199e,
+	  .idProduct		= 0x8102,
+	  .bInterfaceClass	= USB_CLASS_VENDOR_SPEC,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0 },
+	/* Bodelin ProScopeHR */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_DEV_HI
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x19ab,
+	  .idProduct		= 0x1000,
+	  .bcdDevice_hi		= 0x0126,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_QUIRK(UVC_QUIRK_STATUS_INTERVAL) },
+	/* MSI StarCam 370i */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x1b3b,
+	  .idProduct		= 0x2951,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_minmax },
+	/* Generalplus Technology Inc. 808 Camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x1b3f,
+	  .idProduct		= 0x2002,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_probe_minmax },
+	/* Shenzhen Aoni Electronic Co.,Ltd 2K FHD camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x1bcf,
+	  .idProduct		= 0x0b40,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&(const struct uvc_device_info){
+		.uvc_version = 0x010a,
+	  } },
+	/* SiGma Micro USB Web Camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x1c4f,
+	  .idProduct		= 0x3000,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_QUIRK(UVC_QUIRK_PROBE_MINMAX
+					| UVC_QUIRK_IGNORE_SELECTOR_UNIT) },
+	/* Oculus VR Positional Tracker DK2 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x2833,
+	  .idProduct		= 0x0201,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_force_y8 },
+	/* Oculus VR Rift Sensor */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x2833,
+	  .idProduct		= 0x0211,
+	  .bInterfaceClass	= USB_CLASS_VENDOR_SPEC,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_quirk_force_y8 },
+	/* GEO Semiconductor GC6500 */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x29fe,
+	  .idProduct		= 0x4d53,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_QUIRK(UVC_QUIRK_FORCE_BPP) },
+	/* Lenovo Integrated Camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x30c9,
+	  .idProduct		= 0x0093,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= UVC_PC_PROTOCOL_15,
+	  .driver_info		= (kernel_ulong_t)&uvc_ctrl_power_line_uvc11 },
+	/* Sonix Technology USB 2.0 Camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x3277,
+	  .idProduct		= 0x0072,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_ctrl_power_line_limited },
+	/* Acer EasyCamera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x5986,
+	  .idProduct		= 0x1172,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_ctrl_power_line_limited },
+	/* Acer EasyCamera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x5986,
+	  .idProduct		= 0x1180,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= (kernel_ulong_t)&uvc_ctrl_power_line_limited },
+	/* Intel D410/ASR depth camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x8086,
+	  .idProduct		= 0x0ad2,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_META(V4L2_META_FMT_D4XX) },
+	/* Intel D415/ASRC depth camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x8086,
+	  .idProduct		= 0x0ad3,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_META(V4L2_META_FMT_D4XX) },
+	/* Intel D430/AWG depth camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x8086,
+	  .idProduct		= 0x0ad4,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_META(V4L2_META_FMT_D4XX) },
+	/* Intel RealSense D4M */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x8086,
+	  .idProduct		= 0x0b03,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_META(V4L2_META_FMT_D4XX) },
+	/* Intel D435/AWGC depth camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x8086,
+	  .idProduct		= 0x0b07,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_META(V4L2_META_FMT_D4XX) },
+	/* Intel D435i depth camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x8086,
+	  .idProduct		= 0x0b3a,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_META(V4L2_META_FMT_D4XX) },
+	/* Intel D405 Depth Camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x8086,
+	  .idProduct		= 0x0b5b,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_META(V4L2_META_FMT_D4XX) },
+	/* Intel D455 Depth Camera */
+	{ .match_flags		= USB_DEVICE_ID_MATCH_DEVICE
+				| USB_DEVICE_ID_MATCH_INT_INFO,
+	  .idVendor		= 0x8086,
+	  .idProduct		= 0x0b5c,
+	  .bInterfaceClass	= USB_CLASS_VIDEO,
+	  .bInterfaceSubClass	= 1,
+	  .bInterfaceProtocol	= 0,
+	  .driver_info		= UVC_INFO_META(V4L2_META_FMT_D4XX) },
+	/* Generic USB Video Class */
+	{ USB_INTERFACE_INFO(USB_CLASS_VIDEO, 1, UVC_PC_PROTOCOL_UNDEFINED) },
+	{ USB_INTERFACE_INFO(USB_CLASS_VIDEO, 1, UVC_PC_PROTOCOL_15) },
+	{}
+};
+
+MODULE_DEVICE_TABLE(usb, uvc_ids);
+
+struct uvc_driver uvc_driver = {
+	.driver = {
+		.name		= "uvcvideo",
+		.probe		= uvc_probe,
+		.disconnect	= uvc_disconnect,
+		.suspend	= uvc_suspend,
+		.resume		= uvc_resume,
+		.reset_resume	= uvc_reset_resume,
+		.id_table	= uvc_ids,
+		.supports_autosuspend = 1,
+	},
+};
+
+static int __init uvc_init(void)
+{
+	int ret;
+
+	uvc_debugfs_init();
+
+	ret = usb_register(&uvc_driver.driver);
+	if (ret < 0) {
+		uvc_debugfs_cleanup();
+		return ret;
+	}
+
+	return 0;
+}
+
+static void __exit uvc_cleanup(void)
+{
+	usb_deregister(&uvc_driver.driver);
+	uvc_debugfs_cleanup();
+}
+
+module_init(uvc_init);
+module_exit(uvc_cleanup);
+
+MODULE_AUTHOR(DRIVER_AUTHOR);
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRIVER_VERSION);
+
diff --git a/drivers/media/usb/uvc/uvc_entity.c b/drivers/media/usb/uvc/uvc_entity.c
new file mode 100644
index 000000000..cc68dd24e
--- /dev/null
+++ b/drivers/media/usb/uvc/uvc_entity.c
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *      uvc_entity.c  --  USB Video Class driver
+ *
+ *      Copyright (C) 2005-2011
+ *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ */
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/videodev2.h>
+
+#include <media/v4l2-common.h>
+
+#include "uvcvideo.h"
+
+static int uvc_mc_create_links(struct uvc_video_chain *chain,
+				    struct uvc_entity *entity)
+{
+	const u32 flags = MEDIA_LNK_FL_ENABLED | MEDIA_LNK_FL_IMMUTABLE;
+	struct media_entity *sink;
+	unsigned int i;
+	int ret;
+
+	sink = (UVC_ENTITY_TYPE(entity) == UVC_TT_STREAMING)
+	     ? (entity->vdev ? &entity->vdev->entity : NULL)
+	     : &entity->subdev.entity;
+	if (sink == NULL)
+		return 0;
+
+	for (i = 0; i < entity->num_pads; ++i) {
+		struct media_entity *source;
+		struct uvc_entity *remote;
+		u8 remote_pad;
+
+		if (!(entity->pads[i].flags & MEDIA_PAD_FL_SINK))
+			continue;
+
+		remote = uvc_entity_by_id(chain->dev, entity->baSourceID[i]);
+		if (remote == NULL || remote->num_pads == 0)
+			return -EINVAL;
+
+		source = (UVC_ENTITY_TYPE(remote) == UVC_TT_STREAMING)
+		       ? (remote->vdev ? &remote->vdev->entity : NULL)
+		       : &remote->subdev.entity;
+		if (source == NULL)
+			continue;
+
+		remote_pad = remote->num_pads - 1;
+		ret = media_create_pad_link(source, remote_pad,
+					       sink, i, flags);
+		if (ret < 0)
+			return ret;
+	}
+
+	return 0;
+}
+
+static const struct v4l2_subdev_ops uvc_subdev_ops = {
+};
+
+void uvc_mc_cleanup_entity(struct uvc_entity *entity)
+{
+	if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING)
+		media_entity_cleanup(&entity->subdev.entity);
+	else if (entity->vdev != NULL)
+		media_entity_cleanup(&entity->vdev->entity);
+}
+
+static int uvc_mc_init_entity(struct uvc_video_chain *chain,
+			      struct uvc_entity *entity)
+{
+	int ret;
+
+	if (UVC_ENTITY_TYPE(entity) != UVC_TT_STREAMING) {
+		u32 function;
+
+		v4l2_subdev_init(&entity->subdev, &uvc_subdev_ops);
+		strscpy(entity->subdev.name, entity->name,
+			sizeof(entity->subdev.name));
+
+		switch (UVC_ENTITY_TYPE(entity)) {
+		case UVC_VC_SELECTOR_UNIT:
+			function = MEDIA_ENT_F_VID_MUX;
+			break;
+		case UVC_VC_PROCESSING_UNIT:
+		case UVC_VC_EXTENSION_UNIT:
+			/* For lack of a better option. */
+			function = MEDIA_ENT_F_PROC_VIDEO_PIXEL_FORMATTER;
+			break;
+		case UVC_COMPOSITE_CONNECTOR:
+		case UVC_COMPONENT_CONNECTOR:
+			function = MEDIA_ENT_F_CONN_COMPOSITE;
+			break;
+		case UVC_SVIDEO_CONNECTOR:
+			function = MEDIA_ENT_F_CONN_SVIDEO;
+			break;
+		case UVC_ITT_CAMERA:
+			function = MEDIA_ENT_F_CAM_SENSOR;
+			break;
+		case UVC_TT_VENDOR_SPECIFIC:
+		case UVC_ITT_VENDOR_SPECIFIC:
+		case UVC_ITT_MEDIA_TRANSPORT_INPUT:
+		case UVC_OTT_VENDOR_SPECIFIC:
+		case UVC_OTT_DISPLAY:
+		case UVC_OTT_MEDIA_TRANSPORT_OUTPUT:
+		case UVC_EXTERNAL_VENDOR_SPECIFIC:
+		case UVC_EXT_GPIO_UNIT:
+		default:
+			function = MEDIA_ENT_F_V4L2_SUBDEV_UNKNOWN;
+			break;
+		}
+
+		entity->subdev.entity.function = function;
+
+		ret = media_entity_pads_init(&entity->subdev.entity,
+					entity->num_pads, entity->pads);
+
+		if (ret < 0)
+			return ret;
+
+		ret = v4l2_device_register_subdev(&chain->dev->vdev,
+						  &entity->subdev);
+	} else if (entity->vdev != NULL) {
+		ret = media_entity_pads_init(&entity->vdev->entity,
+					entity->num_pads, entity->pads);
+		if (entity->flags & UVC_ENTITY_FLAG_DEFAULT)
+			entity->vdev->entity.flags |= MEDIA_ENT_FL_DEFAULT;
+	} else
+		ret = 0;
+
+	return ret;
+}
+
+int uvc_mc_register_entities(struct uvc_video_chain *chain)
+{
+	struct uvc_entity *entity;
+	int ret;
+
+	list_for_each_entry(entity, &chain->entities, chain) {
+		ret = uvc_mc_init_entity(chain, entity);
+		if (ret < 0) {
+			dev_info(&chain->dev->udev->dev,
+				 "Failed to initialize entity for entity %u\n",
+				 entity->id);
+			return ret;
+		}
+	}
+
+	list_for_each_entry(entity, &chain->entities, chain) {
+		ret = uvc_mc_create_links(chain, entity);
+		if (ret < 0) {
+			dev_info(&chain->dev->udev->dev,
+				 "Failed to create links for entity %u\n",
+				 entity->id);
+			return ret;
+		}
+	}
+
+	return 0;
+}
diff --git a/drivers/media/usb/uvc/uvc_isight.c b/drivers/media/usb/uvc/uvc_isight.c
new file mode 100644
index 000000000..43cda5e76
--- /dev/null
+++ b/drivers/media/usb/uvc/uvc_isight.c
@@ -0,0 +1,140 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *      uvc_isight.c  --  USB Video Class driver - iSight support
+ *
+ *	Copyright (C) 2006-2007
+ *		Ivan N. Zlatev <contact@i-nz.net>
+ *	Copyright (C) 2008-2009
+ *		Laurent Pinchart <laurent.pinchart@ideasonboard.com>
+ */
+
+#include <linux/usb.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+
+#include "uvcvideo.h"
+
+/*
+ * Built-in iSight webcams implements most of UVC 1.0 except a
+ * different packet format. Instead of sending a header at the
+ * beginning of each isochronous transfer payload, the webcam sends a
+ * single header per image (on its own in a packet), followed by
+ * packets containing data only.
+ *
+ * Offset   Size (bytes)	Description
+ * ------------------------------------------------------------------
+ * 0x00	1	Header length
+ * 0x01	1	Flags (UVC-compliant)
+ * 0x02	4	Always equal to '11223344'
+ * 0x06	8	Always equal to 'deadbeefdeadface'
+ * 0x0e	16	Unknown
+ *
+ * The header can be prefixed by an optional, unknown-purpose byte.
+ */
+
+static int isight_decode(struct uvc_video_queue *queue, struct uvc_buffer *buf,
+		const u8 *data, unsigned int len)
+{
+	static const u8 hdr[] = {
+		0x11, 0x22, 0x33, 0x44,
+		0xde, 0xad, 0xbe, 0xef,
+		0xde, 0xad, 0xfa, 0xce
+	};
+
+	struct uvc_streaming *stream = uvc_queue_to_stream(queue);
+	unsigned int maxlen, nbytes;
+	u8 *mem;
+	int is_header = 0;
+
+	if (buf == NULL)
+		return 0;
+
+	if ((len >= 14 && memcmp(&data[2], hdr, 12) == 0) ||
+	    (len >= 15 && memcmp(&data[3], hdr, 12) == 0)) {
+		uvc_dbg(stream->dev, FRAME, "iSight header found\n");
+		is_header = 1;
+	}
+
+	/* Synchronize to the input stream by waiting for a header packet. */
+	if (buf->state != UVC_BUF_STATE_ACTIVE) {
+		if (!is_header) {
+			uvc_dbg(stream->dev, FRAME,
+				"Dropping packet (out of sync)\n");
+			return 0;
+		}
+
+		buf->state = UVC_BUF_STATE_ACTIVE;
+	}
+
+	/*
+	 * Mark the buffer as done if we're at the beginning of a new frame.
+	 *
+	 * Empty buffers (bytesused == 0) don't trigger end of frame detection
+	 * as it doesn't make sense to return an empty buffer.
+	 */
+	if (is_header && buf->bytesused != 0) {
+		buf->state = UVC_BUF_STATE_DONE;
+		return -EAGAIN;
+	}
+
+	/*
+	 * Copy the video data to the buffer. Skip header packets, as they
+	 * contain no data.
+	 */
+	if (!is_header) {
+		maxlen = buf->length - buf->bytesused;
+		mem = buf->mem + buf->bytesused;
+		nbytes = min(len, maxlen);
+		memcpy(mem, data, nbytes);
+		buf->bytesused += nbytes;
+
+		if (len > maxlen || buf->bytesused == buf->length) {
+			uvc_dbg(stream->dev, FRAME,
+				"Frame complete (overflow)\n");
+			buf->state = UVC_BUF_STATE_DONE;
+		}
+	}
+
+	return 0;
+}
+
+void uvc_video_decode_isight(struct uvc_urb *uvc_urb, struct uvc_buffer *buf,
+			struct uvc_buffer *meta_buf)
+{
+	struct urb *urb = uvc_urb->urb;
+	struct uvc_streaming *stream = uvc_urb->stream;
+	int ret, i;
+
+	for (i = 0; i < urb->number_of_packets; ++i) {
+		if (urb->iso_frame_desc[i].status < 0) {
+			uvc_dbg(stream->dev, FRAME,
+				"USB isochronous frame lost (%d)\n",
+				urb->iso_frame_desc[i].status);
+		}
+
+		/*
+		 * Decode the payload packet.
+		 *
+		 * uvc_video_decode is entered twice when a frame transition
+		 * has been detected because the end of frame can only be
+		 * reliably detected when the first packet of the new frame
+		 * is processed. The first pass detects the transition and
+		 * closes the previous frame's buffer, the second pass
+		 * processes the data of the first payload of the new frame.
+		 */
+		do {
+			ret = isight_decode(&stream->queue, buf,
+					urb->transfer_buffer +
+					urb->iso_frame_desc[i].offset,
+					urb->iso_frame_desc[i].actual_length);
+
+			if (buf == NULL)
+				break;
+
+			if (buf->state == UVC_BUF_STATE_DONE ||
+			    buf->state == UVC_BUF_STATE_ERROR)
+				buf = uvc_queue_next_buffer(&stream->queue,
+							buf);
+		} while (ret == -EAGAIN);
+	}
+}
diff --git a/drivers/media/usb/uvc/uvc_metadata.c b/drivers/media/usb/uvc/uvc_metadata.c
new file mode 100644
index 000000000..82de7781f
--- /dev/null
+++ b/drivers/media/usb/uvc/uvc_metadata.c
@@ -0,0 +1,176 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *      uvc_metadata.c  --  USB Video Class driver - Metadata handling
+ *
+ *      Copyright (C) 2016
+ *          Guennadi Liakhovetski (guennadi.liakhovetski@intel.com)
+ */
+
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/videodev2.h>
+
+#include <media/v4l2-ioctl.h>
+#include <media/videobuf2-v4l2.h>
+#include <media/videobuf2-vmalloc.h>
+
+#include "uvcvideo.h"
+
+/* -----------------------------------------------------------------------------
+ * V4L2 ioctls
+ */
+
+static int uvc_meta_v4l2_querycap(struct file *file, void *fh,
+				  struct v4l2_capability *cap)
+{
+	struct v4l2_fh *vfh = file->private_data;
+	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
+	struct uvc_video_chain *chain = stream->chain;
+
+	strscpy(cap->driver, "uvcvideo", sizeof(cap->driver));
+	strscpy(cap->card, stream->dev->name, sizeof(cap->card));
+	usb_make_path(stream->dev->udev, cap->bus_info, sizeof(cap->bus_info));
+	cap->capabilities = V4L2_CAP_DEVICE_CAPS | V4L2_CAP_STREAMING
+			  | chain->caps;
+
+	return 0;
+}
+
+static int uvc_meta_v4l2_get_format(struct file *file, void *fh,
+				    struct v4l2_format *format)
+{
+	struct v4l2_fh *vfh = file->private_data;
+	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
+	struct v4l2_meta_format *fmt = &format->fmt.meta;
+
+	if (format->type != vfh->vdev->queue->type)
+		return -EINVAL;
+
+	memset(fmt, 0, sizeof(*fmt));
+
+	fmt->dataformat = stream->meta.format;
+	fmt->buffersize = UVC_METADATA_BUF_SIZE;
+
+	return 0;
+}
+
+static int uvc_meta_v4l2_try_format(struct file *file, void *fh,
+				    struct v4l2_format *format)
+{
+	struct v4l2_fh *vfh = file->private_data;
+	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
+	struct uvc_device *dev = stream->dev;
+	struct v4l2_meta_format *fmt = &format->fmt.meta;
+	u32 fmeta = fmt->dataformat;
+
+	if (format->type != vfh->vdev->queue->type)
+		return -EINVAL;
+
+	memset(fmt, 0, sizeof(*fmt));
+
+	fmt->dataformat = fmeta == dev->info->meta_format
+			? fmeta : V4L2_META_FMT_UVC;
+	fmt->buffersize = UVC_METADATA_BUF_SIZE;
+
+	return 0;
+}
+
+static int uvc_meta_v4l2_set_format(struct file *file, void *fh,
+				    struct v4l2_format *format)
+{
+	struct v4l2_fh *vfh = file->private_data;
+	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
+	struct v4l2_meta_format *fmt = &format->fmt.meta;
+	int ret;
+
+	ret = uvc_meta_v4l2_try_format(file, fh, format);
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * We could in principle switch at any time, also during streaming.
+	 * Metadata buffers would still be perfectly parseable, but it's more
+	 * consistent and cleaner to disallow that.
+	 */
+	mutex_lock(&stream->mutex);
+
+	if (uvc_queue_allocated(&stream->queue))
+		ret = -EBUSY;
+	else
+		stream->meta.format = fmt->dataformat;
+
+	mutex_unlock(&stream->mutex);
+
+	return ret;
+}
+
+static int uvc_meta_v4l2_enum_formats(struct file *file, void *fh,
+				      struct v4l2_fmtdesc *fdesc)
+{
+	struct v4l2_fh *vfh = file->private_data;
+	struct uvc_streaming *stream = video_get_drvdata(vfh->vdev);
+	struct uvc_device *dev = stream->dev;
+	u32 index = fdesc->index;
+
+	if (fdesc->type != vfh->vdev->queue->type ||
+	    index > 1U || (index && !dev->info->meta_format))
+		return -EINVAL;
+
+	memset(fdesc, 0, sizeof(*fdesc));
+
+	fdesc->type = vfh->vdev->queue->type;
+	fdesc->index = index;
+	fdesc->pixelformat = index ? dev->info->meta_format : V4L2_META_FMT_UVC;
+
+	return 0;
+}
+
+static const struct v4l2_ioctl_ops uvc_meta_ioctl_ops = {
+	.vidioc_querycap		= uvc_meta_v4l2_querycap,
+	.vidioc_g_fmt_meta_cap		= uvc_meta_v4l2_get_format,
+	.vidioc_s_fmt_meta_cap		= uvc_meta_v4l2_set_format,
+	.vidioc_try_fmt_meta_cap	= uvc_meta_v4l2_try_format,
+	.vidioc_enum_fmt_meta_cap	= uvc_meta_v4l2_enum_formats,
+	.vidioc_reqbufs			= vb2_ioctl_reqbufs,
+	.vidioc_querybuf		= vb2_ioctl_querybuf,
+	.vidioc_qbuf			= vb2_ioctl_qbuf,
+	.vidioc_dqbuf			= vb2_ioctl_dqbuf,
+	.vidioc_create_bufs		= vb2_ioctl_create_bufs,
+	.vidioc_prepare_buf		= vb2_ioctl_prepare_buf,
+	.vidioc_streamon		= vb2_ioctl_streamon,
+	.vidioc_streamoff		= vb2_ioctl_streamoff,
+};
+
+/* -----------------------------------------------------------------------------
+ * V4L2 File Operations
+ */
+
+static const struct v4l2_file_operations uvc_meta_fops = {
+	.owner = THIS_MODULE,
+	.unlocked_ioctl = video_ioctl2,
+	.open = v4l2_fh_open,
+	.release = vb2_fop_release,
+	.poll = vb2_fop_poll,
+	.mmap = vb2_fop_mmap,
+};
+
+int uvc_meta_register(struct uvc_streaming *stream)
+{
+	struct uvc_device *dev = stream->dev;
+	struct video_device *vdev = &stream->meta.vdev;
+	struct uvc_video_queue *queue = &stream->meta.queue;
+
+	stream->meta.format = V4L2_META_FMT_UVC;
+
+	/*
+	 * The video interface queue uses manual locking and thus does not set
+	 * the queue pointer. Set it manually here.
+	 */
+	vdev->queue = &queue->queue;
+
+	return uvc_register_video_device(dev, stream, vdev, queue,
+					 V4L2_BUF_TYPE_META_CAPTURE,
+					 &uvc_meta_fops, &uvc_meta_ioctl_ops);
+}
diff --git a/drivers/media/usb/uvc/uvc_queue.c b/drivers/media/usb/uvc/uvc_queue.c
new file mode 100644
index 000000000..16fa17bbd
--- /dev/null
+++ b/drivers/media/usb/uvc/uvc_queue.c
@@ -0,0 +1,517 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *      uvc_queue.c  --  USB Video Class driver - Buffers management
+ *
+ *      Copyright (C) 2005-2010
+ *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ */
+
+#include <linux/atomic.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/usb.h>
+#include <linux/videodev2.h>
+#include <linux/vmalloc.h>
+#include <linux/wait.h>
+#include <media/videobuf2-v4l2.h>
+#include <media/videobuf2-vmalloc.h>
+
+#include "uvcvideo.h"
+
+/* ------------------------------------------------------------------------
+ * Video buffers queue management.
+ *
+ * Video queues is initialized by uvc_queue_init(). The function performs
+ * basic initialization of the uvc_video_queue struct and never fails.
+ *
+ * Video buffers are managed by videobuf2. The driver uses a mutex to protect
+ * the videobuf2 queue operations by serializing calls to videobuf2 and a
+ * spinlock to protect the IRQ queue that holds the buffers to be processed by
+ * the driver.
+ */
+
+static inline struct uvc_buffer *uvc_vbuf_to_buffer(struct vb2_v4l2_buffer *buf)
+{
+	return container_of(buf, struct uvc_buffer, buf);
+}
+
+/*
+ * Return all queued buffers to videobuf2 in the requested state.
+ *
+ * This function must be called with the queue spinlock held.
+ */
+static void uvc_queue_return_buffers(struct uvc_video_queue *queue,
+			       enum uvc_buffer_state state)
+{
+	enum vb2_buffer_state vb2_state = state == UVC_BUF_STATE_ERROR
+					? VB2_BUF_STATE_ERROR
+					: VB2_BUF_STATE_QUEUED;
+
+	while (!list_empty(&queue->irqqueue)) {
+		struct uvc_buffer *buf = list_first_entry(&queue->irqqueue,
+							  struct uvc_buffer,
+							  queue);
+		list_del(&buf->queue);
+		buf->state = state;
+		vb2_buffer_done(&buf->buf.vb2_buf, vb2_state);
+	}
+}
+
+/* -----------------------------------------------------------------------------
+ * videobuf2 queue operations
+ */
+
+static int uvc_queue_setup(struct vb2_queue *vq,
+			   unsigned int *nbuffers, unsigned int *nplanes,
+			   unsigned int sizes[], struct device *alloc_devs[])
+{
+	struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
+	struct uvc_streaming *stream;
+	unsigned int size;
+
+	switch (vq->type) {
+	case V4L2_BUF_TYPE_META_CAPTURE:
+		size = UVC_METADATA_BUF_SIZE;
+		break;
+
+	default:
+		stream = uvc_queue_to_stream(queue);
+		size = stream->ctrl.dwMaxVideoFrameSize;
+		break;
+	}
+
+	/*
+	 * When called with plane sizes, validate them. The driver supports
+	 * single planar formats only, and requires buffers to be large enough
+	 * to store a complete frame.
+	 */
+	if (*nplanes)
+		return *nplanes != 1 || sizes[0] < size ? -EINVAL : 0;
+
+	*nplanes = 1;
+	sizes[0] = size;
+	return 0;
+}
+
+static int uvc_buffer_prepare(struct vb2_buffer *vb)
+{
+	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
+	struct uvc_buffer *buf = uvc_vbuf_to_buffer(vbuf);
+
+	if (vb->type == V4L2_BUF_TYPE_VIDEO_OUTPUT &&
+	    vb2_get_plane_payload(vb, 0) > vb2_plane_size(vb, 0)) {
+		uvc_dbg(uvc_queue_to_stream(queue)->dev, CAPTURE,
+			"[E] Bytes used out of bounds\n");
+		return -EINVAL;
+	}
+
+	if (unlikely(queue->flags & UVC_QUEUE_DISCONNECTED))
+		return -ENODEV;
+
+	buf->state = UVC_BUF_STATE_QUEUED;
+	buf->error = 0;
+	buf->mem = vb2_plane_vaddr(vb, 0);
+	buf->length = vb2_plane_size(vb, 0);
+	if (vb->type != V4L2_BUF_TYPE_VIDEO_OUTPUT)
+		buf->bytesused = 0;
+	else
+		buf->bytesused = vb2_get_plane_payload(vb, 0);
+
+	return 0;
+}
+
+static void uvc_buffer_queue(struct vb2_buffer *vb)
+{
+	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
+	struct uvc_buffer *buf = uvc_vbuf_to_buffer(vbuf);
+	unsigned long flags;
+
+	spin_lock_irqsave(&queue->irqlock, flags);
+	if (likely(!(queue->flags & UVC_QUEUE_DISCONNECTED))) {
+		kref_init(&buf->ref);
+		list_add_tail(&buf->queue, &queue->irqqueue);
+	} else {
+		/*
+		 * If the device is disconnected return the buffer to userspace
+		 * directly. The next QBUF call will fail with -ENODEV.
+		 */
+		buf->state = UVC_BUF_STATE_ERROR;
+		vb2_buffer_done(vb, VB2_BUF_STATE_ERROR);
+	}
+
+	spin_unlock_irqrestore(&queue->irqlock, flags);
+}
+
+static void uvc_buffer_finish(struct vb2_buffer *vb)
+{
+	struct vb2_v4l2_buffer *vbuf = to_vb2_v4l2_buffer(vb);
+	struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
+	struct uvc_streaming *stream = uvc_queue_to_stream(queue);
+	struct uvc_buffer *buf = uvc_vbuf_to_buffer(vbuf);
+
+	if (vb->state == VB2_BUF_STATE_DONE)
+		uvc_video_clock_update(stream, vbuf, buf);
+}
+
+static int uvc_start_streaming(struct vb2_queue *vq, unsigned int count)
+{
+	struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
+	struct uvc_streaming *stream = uvc_queue_to_stream(queue);
+	int ret;
+
+	lockdep_assert_irqs_enabled();
+
+	queue->buf_used = 0;
+
+	ret = uvc_video_start_streaming(stream);
+	if (ret == 0)
+		return 0;
+
+	spin_lock_irq(&queue->irqlock);
+	uvc_queue_return_buffers(queue, UVC_BUF_STATE_QUEUED);
+	spin_unlock_irq(&queue->irqlock);
+
+	return ret;
+}
+
+static void uvc_stop_streaming(struct vb2_queue *vq)
+{
+	struct uvc_video_queue *queue = vb2_get_drv_priv(vq);
+
+	lockdep_assert_irqs_enabled();
+
+	if (vq->type != V4L2_BUF_TYPE_META_CAPTURE)
+		uvc_video_stop_streaming(uvc_queue_to_stream(queue));
+
+	spin_lock_irq(&queue->irqlock);
+	uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR);
+	spin_unlock_irq(&queue->irqlock);
+}
+
+static const struct vb2_ops uvc_queue_qops = {
+	.queue_setup = uvc_queue_setup,
+	.buf_prepare = uvc_buffer_prepare,
+	.buf_queue = uvc_buffer_queue,
+	.buf_finish = uvc_buffer_finish,
+	.wait_prepare = vb2_ops_wait_prepare,
+	.wait_finish = vb2_ops_wait_finish,
+	.start_streaming = uvc_start_streaming,
+	.stop_streaming = uvc_stop_streaming,
+};
+
+static const struct vb2_ops uvc_meta_queue_qops = {
+	.queue_setup = uvc_queue_setup,
+	.buf_prepare = uvc_buffer_prepare,
+	.buf_queue = uvc_buffer_queue,
+	.wait_prepare = vb2_ops_wait_prepare,
+	.wait_finish = vb2_ops_wait_finish,
+	.stop_streaming = uvc_stop_streaming,
+};
+
+int uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
+		    int drop_corrupted)
+{
+	int ret;
+
+	queue->queue.type = type;
+	queue->queue.io_modes = VB2_MMAP | VB2_USERPTR;
+	queue->queue.drv_priv = queue;
+	queue->queue.buf_struct_size = sizeof(struct uvc_buffer);
+	queue->queue.mem_ops = &vb2_vmalloc_memops;
+	queue->queue.timestamp_flags = V4L2_BUF_FLAG_TIMESTAMP_MONOTONIC
+		| V4L2_BUF_FLAG_TSTAMP_SRC_SOE;
+	queue->queue.lock = &queue->mutex;
+
+	switch (type) {
+	case V4L2_BUF_TYPE_META_CAPTURE:
+		queue->queue.ops = &uvc_meta_queue_qops;
+		break;
+	default:
+		queue->queue.io_modes |= VB2_DMABUF;
+		queue->queue.ops = &uvc_queue_qops;
+		break;
+	}
+
+	ret = vb2_queue_init(&queue->queue);
+	if (ret)
+		return ret;
+
+	mutex_init(&queue->mutex);
+	spin_lock_init(&queue->irqlock);
+	INIT_LIST_HEAD(&queue->irqqueue);
+	queue->flags = drop_corrupted ? UVC_QUEUE_DROP_CORRUPTED : 0;
+
+	return 0;
+}
+
+void uvc_queue_release(struct uvc_video_queue *queue)
+{
+	mutex_lock(&queue->mutex);
+	vb2_queue_release(&queue->queue);
+	mutex_unlock(&queue->mutex);
+}
+
+/* -----------------------------------------------------------------------------
+ * V4L2 queue operations
+ */
+
+int uvc_request_buffers(struct uvc_video_queue *queue,
+			struct v4l2_requestbuffers *rb)
+{
+	int ret;
+
+	mutex_lock(&queue->mutex);
+	ret = vb2_reqbufs(&queue->queue, rb);
+	mutex_unlock(&queue->mutex);
+
+	return ret ? ret : rb->count;
+}
+
+int uvc_query_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf)
+{
+	int ret;
+
+	mutex_lock(&queue->mutex);
+	ret = vb2_querybuf(&queue->queue, buf);
+	mutex_unlock(&queue->mutex);
+
+	return ret;
+}
+
+int uvc_create_buffers(struct uvc_video_queue *queue,
+		       struct v4l2_create_buffers *cb)
+{
+	int ret;
+
+	mutex_lock(&queue->mutex);
+	ret = vb2_create_bufs(&queue->queue, cb);
+	mutex_unlock(&queue->mutex);
+
+	return ret;
+}
+
+int uvc_queue_buffer(struct uvc_video_queue *queue,
+		     struct media_device *mdev, struct v4l2_buffer *buf)
+{
+	int ret;
+
+	mutex_lock(&queue->mutex);
+	ret = vb2_qbuf(&queue->queue, mdev, buf);
+	mutex_unlock(&queue->mutex);
+
+	return ret;
+}
+
+int uvc_export_buffer(struct uvc_video_queue *queue,
+		      struct v4l2_exportbuffer *exp)
+{
+	int ret;
+
+	mutex_lock(&queue->mutex);
+	ret = vb2_expbuf(&queue->queue, exp);
+	mutex_unlock(&queue->mutex);
+
+	return ret;
+}
+
+int uvc_dequeue_buffer(struct uvc_video_queue *queue, struct v4l2_buffer *buf,
+		       int nonblocking)
+{
+	int ret;
+
+	mutex_lock(&queue->mutex);
+	ret = vb2_dqbuf(&queue->queue, buf, nonblocking);
+	mutex_unlock(&queue->mutex);
+
+	return ret;
+}
+
+int uvc_queue_streamon(struct uvc_video_queue *queue, enum v4l2_buf_type type)
+{
+	int ret;
+
+	mutex_lock(&queue->mutex);
+	ret = vb2_streamon(&queue->queue, type);
+	mutex_unlock(&queue->mutex);
+
+	return ret;
+}
+
+int uvc_queue_streamoff(struct uvc_video_queue *queue, enum v4l2_buf_type type)
+{
+	int ret;
+
+	mutex_lock(&queue->mutex);
+	ret = vb2_streamoff(&queue->queue, type);
+	mutex_unlock(&queue->mutex);
+
+	return ret;
+}
+
+int uvc_queue_mmap(struct uvc_video_queue *queue, struct vm_area_struct *vma)
+{
+	return vb2_mmap(&queue->queue, vma);
+}
+
+#ifndef CONFIG_MMU
+unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
+		unsigned long pgoff)
+{
+	return vb2_get_unmapped_area(&queue->queue, 0, 0, pgoff, 0);
+}
+#endif
+
+__poll_t uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
+			    poll_table *wait)
+{
+	__poll_t ret;
+
+	mutex_lock(&queue->mutex);
+	ret = vb2_poll(&queue->queue, file, wait);
+	mutex_unlock(&queue->mutex);
+
+	return ret;
+}
+
+/* -----------------------------------------------------------------------------
+ *
+ */
+
+/*
+ * Check if buffers have been allocated.
+ */
+int uvc_queue_allocated(struct uvc_video_queue *queue)
+{
+	int allocated;
+
+	mutex_lock(&queue->mutex);
+	allocated = vb2_is_busy(&queue->queue);
+	mutex_unlock(&queue->mutex);
+
+	return allocated;
+}
+
+/*
+ * Cancel the video buffers queue.
+ *
+ * Cancelling the queue marks all buffers on the irq queue as erroneous,
+ * wakes them up and removes them from the queue.
+ *
+ * If the disconnect parameter is set, further calls to uvc_queue_buffer will
+ * fail with -ENODEV.
+ *
+ * This function acquires the irq spinlock and can be called from interrupt
+ * context.
+ */
+void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&queue->irqlock, flags);
+	uvc_queue_return_buffers(queue, UVC_BUF_STATE_ERROR);
+	/*
+	 * This must be protected by the irqlock spinlock to avoid race
+	 * conditions between uvc_buffer_queue and the disconnection event that
+	 * could result in an interruptible wait in uvc_dequeue_buffer. Do not
+	 * blindly replace this logic by checking for the UVC_QUEUE_DISCONNECTED
+	 * state outside the queue code.
+	 */
+	if (disconnect)
+		queue->flags |= UVC_QUEUE_DISCONNECTED;
+	spin_unlock_irqrestore(&queue->irqlock, flags);
+}
+
+/*
+ * uvc_queue_get_current_buffer: Obtain the current working output buffer
+ *
+ * Buffers may span multiple packets, and even URBs, therefore the active buffer
+ * remains on the queue until the EOF marker.
+ */
+static struct uvc_buffer *
+__uvc_queue_get_current_buffer(struct uvc_video_queue *queue)
+{
+	if (list_empty(&queue->irqqueue))
+		return NULL;
+
+	return list_first_entry(&queue->irqqueue, struct uvc_buffer, queue);
+}
+
+struct uvc_buffer *uvc_queue_get_current_buffer(struct uvc_video_queue *queue)
+{
+	struct uvc_buffer *nextbuf;
+	unsigned long flags;
+
+	spin_lock_irqsave(&queue->irqlock, flags);
+	nextbuf = __uvc_queue_get_current_buffer(queue);
+	spin_unlock_irqrestore(&queue->irqlock, flags);
+
+	return nextbuf;
+}
+
+/*
+ * uvc_queue_buffer_requeue: Requeue a buffer on our internal irqqueue
+ *
+ * Reuse a buffer through our internal queue without the need to 'prepare'.
+ * The buffer will be returned to userspace through the uvc_buffer_queue call if
+ * the device has been disconnected.
+ */
+static void uvc_queue_buffer_requeue(struct uvc_video_queue *queue,
+		struct uvc_buffer *buf)
+{
+	buf->error = 0;
+	buf->state = UVC_BUF_STATE_QUEUED;
+	buf->bytesused = 0;
+	vb2_set_plane_payload(&buf->buf.vb2_buf, 0, 0);
+
+	uvc_buffer_queue(&buf->buf.vb2_buf);
+}
+
+static void uvc_queue_buffer_complete(struct kref *ref)
+{
+	struct uvc_buffer *buf = container_of(ref, struct uvc_buffer, ref);
+	struct vb2_buffer *vb = &buf->buf.vb2_buf;
+	struct uvc_video_queue *queue = vb2_get_drv_priv(vb->vb2_queue);
+
+	if ((queue->flags & UVC_QUEUE_DROP_CORRUPTED) && buf->error) {
+		uvc_queue_buffer_requeue(queue, buf);
+		return;
+	}
+
+	buf->state = buf->error ? UVC_BUF_STATE_ERROR : UVC_BUF_STATE_DONE;
+	vb2_set_plane_payload(&buf->buf.vb2_buf, 0, buf->bytesused);
+	vb2_buffer_done(&buf->buf.vb2_buf, VB2_BUF_STATE_DONE);
+}
+
+/*
+ * Release a reference on the buffer. Complete the buffer when the last
+ * reference is released.
+ */
+void uvc_queue_buffer_release(struct uvc_buffer *buf)
+{
+	kref_put(&buf->ref, uvc_queue_buffer_complete);
+}
+
+/*
+ * Remove this buffer from the queue. Lifetime will persist while async actions
+ * are still running (if any), and uvc_queue_buffer_release will give the buffer
+ * back to VB2 when all users have completed.
+ */
+struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
+		struct uvc_buffer *buf)
+{
+	struct uvc_buffer *nextbuf;
+	unsigned long flags;
+
+	spin_lock_irqsave(&queue->irqlock, flags);
+	list_del(&buf->queue);
+	nextbuf = __uvc_queue_get_current_buffer(queue);
+	spin_unlock_irqrestore(&queue->irqlock, flags);
+
+	uvc_queue_buffer_release(buf);
+
+	return nextbuf;
+}
diff --git a/drivers/media/usb/uvc/uvc_status.c b/drivers/media/usb/uvc/uvc_status.c
new file mode 100644
index 000000000..a78a88c71
--- /dev/null
+++ b/drivers/media/usb/uvc/uvc_status.c
@@ -0,0 +1,352 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *      uvc_status.c  --  USB Video Class driver - Status endpoint
+ *
+ *      Copyright (C) 2005-2009
+ *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ */
+
+#include <asm/barrier.h>
+#include <linux/kernel.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/usb/input.h>
+
+#include "uvcvideo.h"
+
+/* --------------------------------------------------------------------------
+ * Input device
+ */
+#ifdef CONFIG_USB_VIDEO_CLASS_INPUT_EVDEV
+
+static bool uvc_input_has_button(struct uvc_device *dev)
+{
+	struct uvc_streaming *stream;
+
+	/*
+	 * The device has button events if both bTriggerSupport and
+	 * bTriggerUsage are one. Otherwise the camera button does not
+	 * exist or is handled automatically by the camera without host
+	 * driver or client application intervention.
+	 */
+	list_for_each_entry(stream, &dev->streams, list) {
+		if (stream->header.bTriggerSupport == 1 &&
+		    stream->header.bTriggerUsage == 1)
+			return true;
+	}
+
+	return false;
+}
+
+static int uvc_input_init(struct uvc_device *dev)
+{
+	struct input_dev *input;
+	int ret;
+
+	if (!uvc_input_has_button(dev))
+		return 0;
+
+	input = input_allocate_device();
+	if (input == NULL)
+		return -ENOMEM;
+
+	usb_make_path(dev->udev, dev->input_phys, sizeof(dev->input_phys));
+	strlcat(dev->input_phys, "/button", sizeof(dev->input_phys));
+
+	input->name = dev->name;
+	input->phys = dev->input_phys;
+	usb_to_input_id(dev->udev, &input->id);
+	input->dev.parent = &dev->intf->dev;
+
+	__set_bit(EV_KEY, input->evbit);
+	__set_bit(KEY_CAMERA, input->keybit);
+
+	if ((ret = input_register_device(input)) < 0)
+		goto error;
+
+	dev->input = input;
+	return 0;
+
+error:
+	input_free_device(input);
+	return ret;
+}
+
+static void uvc_input_unregister(struct uvc_device *dev)
+{
+	if (dev->input)
+		input_unregister_device(dev->input);
+}
+
+static void uvc_input_report_key(struct uvc_device *dev, unsigned int code,
+	int value)
+{
+	if (dev->input) {
+		input_report_key(dev->input, code, value);
+		input_sync(dev->input);
+	}
+}
+
+#else
+#define uvc_input_init(dev)
+#define uvc_input_unregister(dev)
+#define uvc_input_report_key(dev, code, value)
+#endif /* CONFIG_USB_VIDEO_CLASS_INPUT_EVDEV */
+
+/* --------------------------------------------------------------------------
+ * Status interrupt endpoint
+ */
+static void uvc_event_streaming(struct uvc_device *dev,
+				struct uvc_status *status, int len)
+{
+	if (len <= offsetof(struct uvc_status, bEvent)) {
+		uvc_dbg(dev, STATUS,
+			"Invalid streaming status event received\n");
+		return;
+	}
+
+	if (status->bEvent == 0) {
+		if (len <= offsetof(struct uvc_status, streaming))
+			return;
+
+		uvc_dbg(dev, STATUS, "Button (intf %u) %s len %d\n",
+			status->bOriginator,
+			status->streaming.button ? "pressed" : "released", len);
+		uvc_input_report_key(dev, KEY_CAMERA, status->streaming.button);
+	} else {
+		uvc_dbg(dev, STATUS, "Stream %u error event %02x len %d\n",
+			status->bOriginator, status->bEvent, len);
+	}
+}
+
+#define UVC_CTRL_VALUE_CHANGE	0
+#define UVC_CTRL_INFO_CHANGE	1
+#define UVC_CTRL_FAILURE_CHANGE	2
+#define UVC_CTRL_MIN_CHANGE	3
+#define UVC_CTRL_MAX_CHANGE	4
+
+static struct uvc_control *uvc_event_entity_find_ctrl(struct uvc_entity *entity,
+						      u8 selector)
+{
+	struct uvc_control *ctrl;
+	unsigned int i;
+
+	for (i = 0, ctrl = entity->controls; i < entity->ncontrols; i++, ctrl++)
+		if (ctrl->info.selector == selector)
+			return ctrl;
+
+	return NULL;
+}
+
+static struct uvc_control *uvc_event_find_ctrl(struct uvc_device *dev,
+					const struct uvc_status *status,
+					struct uvc_video_chain **chain)
+{
+	list_for_each_entry((*chain), &dev->chains, list) {
+		struct uvc_entity *entity;
+		struct uvc_control *ctrl;
+
+		list_for_each_entry(entity, &(*chain)->entities, chain) {
+			if (entity->id != status->bOriginator)
+				continue;
+
+			ctrl = uvc_event_entity_find_ctrl(entity,
+						     status->control.bSelector);
+			if (ctrl)
+				return ctrl;
+		}
+	}
+
+	return NULL;
+}
+
+static bool uvc_event_control(struct urb *urb,
+			      const struct uvc_status *status, int len)
+{
+	static const char *attrs[] = { "value", "info", "failure", "min", "max" };
+	struct uvc_device *dev = urb->context;
+	struct uvc_video_chain *chain;
+	struct uvc_control *ctrl;
+
+	if (len < 6 || status->bEvent != 0 ||
+	    status->control.bAttribute >= ARRAY_SIZE(attrs)) {
+		uvc_dbg(dev, STATUS, "Invalid control status event received\n");
+		return false;
+	}
+
+	uvc_dbg(dev, STATUS, "Control %u/%u %s change len %d\n",
+		status->bOriginator, status->control.bSelector,
+		attrs[status->control.bAttribute], len);
+
+	/* Find the control. */
+	ctrl = uvc_event_find_ctrl(dev, status, &chain);
+	if (!ctrl)
+		return false;
+
+	switch (status->control.bAttribute) {
+	case UVC_CTRL_VALUE_CHANGE:
+		return uvc_ctrl_status_event_async(urb, chain, ctrl,
+						   status->control.bValue);
+
+	case UVC_CTRL_INFO_CHANGE:
+	case UVC_CTRL_FAILURE_CHANGE:
+	case UVC_CTRL_MIN_CHANGE:
+	case UVC_CTRL_MAX_CHANGE:
+		break;
+	}
+
+	return false;
+}
+
+static void uvc_status_complete(struct urb *urb)
+{
+	struct uvc_device *dev = urb->context;
+	int len, ret;
+
+	switch (urb->status) {
+	case 0:
+		break;
+
+	case -ENOENT:		/* usb_kill_urb() called. */
+	case -ECONNRESET:	/* usb_unlink_urb() called. */
+	case -ESHUTDOWN:	/* The endpoint is being disabled. */
+	case -EPROTO:		/* Device is disconnected (reported by some host controllers). */
+		return;
+
+	default:
+		dev_warn(&dev->udev->dev,
+			 "Non-zero status (%d) in status completion handler.\n",
+			 urb->status);
+		return;
+	}
+
+	len = urb->actual_length;
+	if (len > 0) {
+		switch (dev->status->bStatusType & 0x0f) {
+		case UVC_STATUS_TYPE_CONTROL: {
+			if (uvc_event_control(urb, dev->status, len))
+				/* The URB will be resubmitted in work context. */
+				return;
+			break;
+		}
+
+		case UVC_STATUS_TYPE_STREAMING: {
+			uvc_event_streaming(dev, dev->status, len);
+			break;
+		}
+
+		default:
+			uvc_dbg(dev, STATUS, "Unknown status event type %u\n",
+				dev->status->bStatusType);
+			break;
+		}
+	}
+
+	/* Resubmit the URB. */
+	urb->interval = dev->int_ep->desc.bInterval;
+	ret = usb_submit_urb(urb, GFP_ATOMIC);
+	if (ret < 0)
+		dev_err(&dev->udev->dev,
+			"Failed to resubmit status URB (%d).\n", ret);
+}
+
+int uvc_status_init(struct uvc_device *dev)
+{
+	struct usb_host_endpoint *ep = dev->int_ep;
+	unsigned int pipe;
+	int interval;
+
+	if (ep == NULL)
+		return 0;
+
+	uvc_input_init(dev);
+
+	dev->status = kzalloc(sizeof(*dev->status), GFP_KERNEL);
+	if (!dev->status)
+		return -ENOMEM;
+
+	dev->int_urb = usb_alloc_urb(0, GFP_KERNEL);
+	if (!dev->int_urb) {
+		kfree(dev->status);
+		return -ENOMEM;
+	}
+
+	pipe = usb_rcvintpipe(dev->udev, ep->desc.bEndpointAddress);
+
+	/*
+	 * For high-speed interrupt endpoints, the bInterval value is used as
+	 * an exponent of two. Some developers forgot about it.
+	 */
+	interval = ep->desc.bInterval;
+	if (interval > 16 && dev->udev->speed == USB_SPEED_HIGH &&
+	    (dev->quirks & UVC_QUIRK_STATUS_INTERVAL))
+		interval = fls(interval) - 1;
+
+	usb_fill_int_urb(dev->int_urb, dev->udev, pipe,
+		dev->status, sizeof(*dev->status), uvc_status_complete,
+		dev, interval);
+
+	return 0;
+}
+
+void uvc_status_unregister(struct uvc_device *dev)
+{
+	usb_kill_urb(dev->int_urb);
+	uvc_input_unregister(dev);
+}
+
+void uvc_status_cleanup(struct uvc_device *dev)
+{
+	usb_free_urb(dev->int_urb);
+	kfree(dev->status);
+}
+
+int uvc_status_start(struct uvc_device *dev, gfp_t flags)
+{
+	if (dev->int_urb == NULL)
+		return 0;
+
+	return usb_submit_urb(dev->int_urb, flags);
+}
+
+void uvc_status_stop(struct uvc_device *dev)
+{
+	struct uvc_ctrl_work *w = &dev->async_ctrl;
+
+	/*
+	 * Prevent the asynchronous control handler from requeing the URB. The
+	 * barrier is needed so the flush_status change is visible to other
+	 * CPUs running the asynchronous handler before usb_kill_urb() is
+	 * called below.
+	 */
+	smp_store_release(&dev->flush_status, true);
+
+	/*
+	 * Cancel any pending asynchronous work. If any status event was queued,
+	 * process it synchronously.
+	 */
+	if (cancel_work_sync(&w->work))
+		uvc_ctrl_status_event(w->chain, w->ctrl, w->data);
+
+	/* Kill the urb. */
+	usb_kill_urb(dev->int_urb);
+
+	/*
+	 * The URB completion handler may have queued asynchronous work. This
+	 * won't resubmit the URB as flush_status is set, but it needs to be
+	 * cancelled before returning or it could then race with a future
+	 * uvc_status_start() call.
+	 */
+	if (cancel_work_sync(&w->work))
+		uvc_ctrl_status_event(w->chain, w->ctrl, w->data);
+
+	/*
+	 * From this point, there are no events on the queue and the status URB
+	 * is dead. No events will be queued until uvc_status_start() is called.
+	 * The barrier is needed to make sure that flush_status is visible to
+	 * uvc_ctrl_status_event_work() when uvc_status_start() will be called
+	 * again.
+	 */
+	smp_store_release(&dev->flush_status, false);
+}
diff --git a/drivers/media/usb/uvc/uvc_v4l2.c b/drivers/media/usb/uvc/uvc_v4l2.c
new file mode 100644
index 000000000..f4988f036
--- /dev/null
+++ b/drivers/media/usb/uvc/uvc_v4l2.c
@@ -0,0 +1,1607 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *      uvc_v4l2.c  --  USB Video Class driver - V4L2 API
+ *
+ *      Copyright (C) 2005-2010
+ *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ */
+
+#include <linux/bits.h>
+#include <linux/compat.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/videodev2.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+#include <linux/wait.h>
+#include <linux/atomic.h>
+
+#include <media/v4l2-common.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-ioctl.h>
+
+#include "uvcvideo.h"
+
+static int uvc_control_add_xu_mapping(struct uvc_video_chain *chain,
+				      struct uvc_control_mapping *map,
+				      const struct uvc_xu_control_mapping *xmap)
+{
+	unsigned int i;
+	size_t size;
+	int ret;
+
+	/*
+	 * Prevent excessive memory consumption, as well as integer
+	 * overflows.
+	 */
+	if (xmap->menu_count == 0 ||
+	    xmap->menu_count > UVC_MAX_CONTROL_MENU_ENTRIES)
+		return -EINVAL;
+
+	map->menu_names = NULL;
+	map->menu_mapping = NULL;
+
+	map->menu_mask = GENMASK(xmap->menu_count - 1, 0);
+
+	size = xmap->menu_count * sizeof(*map->menu_mapping);
+	map->menu_mapping = kzalloc(size, GFP_KERNEL);
+	if (!map->menu_mapping) {
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	for (i = 0; i < xmap->menu_count ; i++) {
+		if (copy_from_user((u32 *)&map->menu_mapping[i],
+				   &xmap->menu_info[i].value,
+				   sizeof(map->menu_mapping[i]))) {
+			ret = -EACCES;
+			goto done;
+		}
+	}
+
+	/*
+	 * Always use the standard naming if available, otherwise copy the
+	 * names supplied by userspace.
+	 */
+	if (!v4l2_ctrl_get_menu(map->id)) {
+		size = xmap->menu_count * sizeof(map->menu_names[0]);
+		map->menu_names = kzalloc(size, GFP_KERNEL);
+		if (!map->menu_names) {
+			ret = -ENOMEM;
+			goto done;
+		}
+
+		for (i = 0; i < xmap->menu_count ; i++) {
+			/* sizeof(names[i]) - 1: to take care of \0 */
+			if (copy_from_user((char *)map->menu_names[i],
+					   xmap->menu_info[i].name,
+					   sizeof(map->menu_names[i]) - 1)) {
+				ret = -EACCES;
+				goto done;
+			}
+		}
+	}
+
+	ret = uvc_ctrl_add_mapping(chain, map);
+
+done:
+	kfree(map->menu_names);
+	map->menu_names = NULL;
+	kfree(map->menu_mapping);
+	map->menu_mapping = NULL;
+
+	return ret;
+}
+
+/* ------------------------------------------------------------------------
+ * UVC ioctls
+ */
+static int uvc_ioctl_xu_ctrl_map(struct uvc_video_chain *chain,
+				 struct uvc_xu_control_mapping *xmap)
+{
+	struct uvc_control_mapping *map;
+	int ret;
+
+	map = kzalloc(sizeof(*map), GFP_KERNEL);
+	if (map == NULL)
+		return -ENOMEM;
+
+	map->id = xmap->id;
+	/* Non standard control id. */
+	if (v4l2_ctrl_get_name(map->id) == NULL) {
+		if (xmap->name[0] == '\0') {
+			ret = -EINVAL;
+			goto free_map;
+		}
+		xmap->name[sizeof(xmap->name) - 1] = '\0';
+		map->name = xmap->name;
+	}
+	memcpy(map->entity, xmap->entity, sizeof(map->entity));
+	map->selector = xmap->selector;
+	map->size = xmap->size;
+	map->offset = xmap->offset;
+	map->v4l2_type = xmap->v4l2_type;
+	map->data_type = xmap->data_type;
+
+	switch (xmap->v4l2_type) {
+	case V4L2_CTRL_TYPE_INTEGER:
+	case V4L2_CTRL_TYPE_BOOLEAN:
+	case V4L2_CTRL_TYPE_BUTTON:
+		ret = uvc_ctrl_add_mapping(chain, map);
+		break;
+
+	case V4L2_CTRL_TYPE_MENU:
+		ret = uvc_control_add_xu_mapping(chain, map, xmap);
+		break;
+
+	default:
+		uvc_dbg(chain->dev, CONTROL,
+			"Unsupported V4L2 control type %u\n", xmap->v4l2_type);
+		ret = -ENOTTY;
+		break;
+	}
+
+free_map:
+	kfree(map);
+
+	return ret;
+}
+
+/* ------------------------------------------------------------------------
+ * V4L2 interface
+ */
+
+/*
+ * 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
+ * that feature.
+ */
+static u32 uvc_try_frame_interval(const struct uvc_frame *frame, u32 interval)
+{
+	unsigned int i;
+
+	if (frame->bFrameIntervalType) {
+		u32 best = -1, dist;
+
+		for (i = 0; i < frame->bFrameIntervalType; ++i) {
+			dist = interval > frame->dwFrameInterval[i]
+			     ? interval - frame->dwFrameInterval[i]
+			     : frame->dwFrameInterval[i] - interval;
+
+			if (dist > best)
+				break;
+
+			best = dist;
+		}
+
+		interval = frame->dwFrameInterval[i-1];
+	} else {
+		const u32 min = frame->dwFrameInterval[0];
+		const u32 max = frame->dwFrameInterval[1];
+		const u32 step = frame->dwFrameInterval[2];
+
+		interval = min + (interval - min + step/2) / step * step;
+		if (interval > max)
+			interval = max;
+	}
+
+	return interval;
+}
+
+static u32 uvc_v4l2_get_bytesperline(const struct uvc_format *format,
+	const struct uvc_frame *frame)
+{
+	switch (format->fcc) {
+	case V4L2_PIX_FMT_NV12:
+	case V4L2_PIX_FMT_YVU420:
+	case V4L2_PIX_FMT_YUV420:
+	case V4L2_PIX_FMT_M420:
+		return frame->wWidth;
+
+	default:
+		return format->bpp * frame->wWidth / 8;
+	}
+}
+
+static int uvc_v4l2_try_format(struct uvc_streaming *stream,
+	struct v4l2_format *fmt, struct uvc_streaming_control *probe,
+	const struct uvc_format **uvc_format,
+	const struct uvc_frame **uvc_frame)
+{
+	const struct uvc_format *format = NULL;
+	const struct uvc_frame *frame = NULL;
+	u16 rw, rh;
+	unsigned int d, maxd;
+	unsigned int i;
+	u32 interval;
+	int ret = 0;
+	u8 *fcc;
+
+	if (fmt->type != stream->type)
+		return -EINVAL;
+
+	fcc = (u8 *)&fmt->fmt.pix.pixelformat;
+	uvc_dbg(stream->dev, FORMAT, "Trying format 0x%08x (%c%c%c%c): %ux%u\n",
+		fmt->fmt.pix.pixelformat,
+		fcc[0], fcc[1], fcc[2], fcc[3],
+		fmt->fmt.pix.width, fmt->fmt.pix.height);
+
+	/*
+	 * Check if the hardware supports the requested format, use the default
+	 * format otherwise.
+	 */
+	for (i = 0; i < stream->nformats; ++i) {
+		format = &stream->formats[i];
+		if (format->fcc == fmt->fmt.pix.pixelformat)
+			break;
+	}
+
+	if (i == stream->nformats) {
+		format = stream->def_format;
+		fmt->fmt.pix.pixelformat = format->fcc;
+	}
+
+	/*
+	 * Find the closest image size. The distance between image sizes is
+	 * the size in pixels of the non-overlapping regions between the
+	 * requested size and the frame-specified size.
+	 */
+	rw = fmt->fmt.pix.width;
+	rh = fmt->fmt.pix.height;
+	maxd = (unsigned int)-1;
+
+	for (i = 0; i < format->nframes; ++i) {
+		u16 w = format->frames[i].wWidth;
+		u16 h = format->frames[i].wHeight;
+
+		d = min(w, rw) * min(h, rh);
+		d = w*h + rw*rh - 2*d;
+		if (d < maxd) {
+			maxd = d;
+			frame = &format->frames[i];
+		}
+
+		if (maxd == 0)
+			break;
+	}
+
+	if (frame == NULL) {
+		uvc_dbg(stream->dev, FORMAT, "Unsupported size %ux%u\n",
+			fmt->fmt.pix.width, fmt->fmt.pix.height);
+		return -EINVAL;
+	}
+
+	/* Use the default frame interval. */
+	interval = frame->dwDefaultFrameInterval;
+	uvc_dbg(stream->dev, FORMAT,
+		"Using default frame interval %u.%u us (%u.%u fps)\n",
+		interval / 10, interval % 10, 10000000 / interval,
+		(100000000 / interval) % 10);
+
+	/* Set the format index, frame index and frame interval. */
+	memset(probe, 0, sizeof(*probe));
+	probe->bmHint = 1;	/* dwFrameInterval */
+	probe->bFormatIndex = format->index;
+	probe->bFrameIndex = frame->bFrameIndex;
+	probe->dwFrameInterval = uvc_try_frame_interval(frame, interval);
+	/*
+	 * Some webcams stall the probe control set request when the
+	 * dwMaxVideoFrameSize field is set to zero. The UVC specification
+	 * clearly states that the field is read-only from the host, so this
+	 * is a webcam bug. Set dwMaxVideoFrameSize to the value reported by
+	 * the webcam to work around the problem.
+	 *
+	 * The workaround could probably be enabled for all webcams, so the
+	 * quirk can be removed if needed. It's currently useful to detect
+	 * webcam bugs and fix them before they hit the market (providing
+	 * 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)
+		return ret;
+
+	/*
+	 * After the probe, update fmt with the values returned from
+	 * negotiation with the device. Some devices return invalid bFormatIndex
+	 * and bFrameIndex values, in which case we can only assume they have
+	 * accepted the requested format as-is.
+	 */
+	for (i = 0; i < stream->nformats; ++i) {
+		if (probe->bFormatIndex == stream->formats[i].index) {
+			format = &stream->formats[i];
+			break;
+		}
+	}
+
+	if (i == stream->nformats)
+		uvc_dbg(stream->dev, FORMAT,
+			"Unknown bFormatIndex %u, using default\n",
+			probe->bFormatIndex);
+
+	for (i = 0; i < format->nframes; ++i) {
+		if (probe->bFrameIndex == format->frames[i].bFrameIndex) {
+			frame = &format->frames[i];
+			break;
+		}
+	}
+
+	if (i == format->nframes)
+		uvc_dbg(stream->dev, FORMAT,
+			"Unknown bFrameIndex %u, using default\n",
+			probe->bFrameIndex);
+
+	fmt->fmt.pix.width = frame->wWidth;
+	fmt->fmt.pix.height = frame->wHeight;
+	fmt->fmt.pix.field = V4L2_FIELD_NONE;
+	fmt->fmt.pix.bytesperline = uvc_v4l2_get_bytesperline(format, frame);
+	fmt->fmt.pix.sizeimage = probe->dwMaxVideoFrameSize;
+	fmt->fmt.pix.pixelformat = format->fcc;
+	fmt->fmt.pix.colorspace = format->colorspace;
+	fmt->fmt.pix.xfer_func = format->xfer_func;
+	fmt->fmt.pix.ycbcr_enc = format->ycbcr_enc;
+
+	if (uvc_format != NULL)
+		*uvc_format = format;
+	if (uvc_frame != NULL)
+		*uvc_frame = frame;
+
+	return ret;
+}
+
+static int uvc_v4l2_get_format(struct uvc_streaming *stream,
+	struct v4l2_format *fmt)
+{
+	const struct uvc_format *format;
+	const struct uvc_frame *frame;
+	int ret = 0;
+
+	if (fmt->type != stream->type)
+		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;
+	fmt->fmt.pix.height = frame->wHeight;
+	fmt->fmt.pix.field = V4L2_FIELD_NONE;
+	fmt->fmt.pix.bytesperline = uvc_v4l2_get_bytesperline(format, frame);
+	fmt->fmt.pix.sizeimage = stream->ctrl.dwMaxVideoFrameSize;
+	fmt->fmt.pix.colorspace = format->colorspace;
+	fmt->fmt.pix.xfer_func = format->xfer_func;
+	fmt->fmt.pix.ycbcr_enc = format->ycbcr_enc;
+
+done:
+	mutex_unlock(&stream->mutex);
+	return ret;
+}
+
+static int uvc_v4l2_set_format(struct uvc_streaming *stream,
+	struct v4l2_format *fmt)
+{
+	struct uvc_streaming_control probe;
+	const struct uvc_format *format;
+	const struct uvc_frame *frame;
+	int ret;
+
+	if (fmt->type != stream->type)
+		return -EINVAL;
+
+	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;
+	}
+
+	stream->ctrl = probe;
+	stream->cur_format = format;
+	stream->cur_frame = frame;
+
+done:
+	mutex_unlock(&stream->mutex);
+	return ret;
+}
+
+static int uvc_v4l2_get_streamparm(struct uvc_streaming *stream,
+		struct v4l2_streamparm *parm)
+{
+	u32 numerator, denominator;
+
+	if (parm->type != stream->type)
+		return -EINVAL;
+
+	mutex_lock(&stream->mutex);
+	numerator = stream->ctrl.dwFrameInterval;
+	mutex_unlock(&stream->mutex);
+
+	denominator = 10000000;
+	v4l2_simplify_fraction(&numerator, &denominator, 8, 333);
+
+	memset(parm, 0, sizeof(*parm));
+	parm->type = stream->type;
+
+	if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+		parm->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
+		parm->parm.capture.capturemode = 0;
+		parm->parm.capture.timeperframe.numerator = numerator;
+		parm->parm.capture.timeperframe.denominator = denominator;
+		parm->parm.capture.extendedmode = 0;
+		parm->parm.capture.readbuffers = 0;
+	} else {
+		parm->parm.output.capability = V4L2_CAP_TIMEPERFRAME;
+		parm->parm.output.outputmode = 0;
+		parm->parm.output.timeperframe.numerator = numerator;
+		parm->parm.output.timeperframe.denominator = denominator;
+	}
+
+	return 0;
+}
+
+static int uvc_v4l2_set_streamparm(struct uvc_streaming *stream,
+		struct v4l2_streamparm *parm)
+{
+	struct uvc_streaming_control probe;
+	struct v4l2_fract timeperframe;
+	const struct uvc_format *format;
+	const struct uvc_frame *frame;
+	u32 interval, maxd;
+	unsigned int i;
+	int ret;
+
+	if (parm->type != stream->type)
+		return -EINVAL;
+
+	if (parm->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
+		timeperframe = parm->parm.capture.timeperframe;
+	else
+		timeperframe = parm->parm.output.timeperframe;
+
+	interval = v4l2_fraction_to_interval(timeperframe.numerator,
+		timeperframe.denominator);
+	uvc_dbg(stream->dev, FORMAT, "Setting frame interval to %u/%u (%u)\n",
+		timeperframe.numerator, timeperframe.denominator, interval);
+
+	mutex_lock(&stream->mutex);
+
+	if (uvc_queue_streaming(&stream->queue)) {
+		mutex_unlock(&stream->mutex);
+		return -EBUSY;
+	}
+
+	format = stream->cur_format;
+	frame = stream->cur_frame;
+	probe = stream->ctrl;
+	probe.dwFrameInterval = uvc_try_frame_interval(frame, interval);
+	maxd = abs((s32)probe.dwFrameInterval - interval);
+
+	/* Try frames with matching size to find the best frame interval. */
+	for (i = 0; i < format->nframes && maxd != 0; i++) {
+		u32 d, ival;
+
+		if (&format->frames[i] == stream->cur_frame)
+			continue;
+
+		if (format->frames[i].wWidth != stream->cur_frame->wWidth ||
+		    format->frames[i].wHeight != stream->cur_frame->wHeight)
+			continue;
+
+		ival = uvc_try_frame_interval(&format->frames[i], interval);
+		d = abs((s32)ival - interval);
+		if (d >= maxd)
+			continue;
+
+		frame = &format->frames[i];
+		probe.bFrameIndex = frame->bFrameIndex;
+		probe.dwFrameInterval = ival;
+		maxd = d;
+	}
+
+	/* Probe the device with the new settings. */
+	ret = uvc_probe_video(stream, &probe);
+	if (ret < 0) {
+		mutex_unlock(&stream->mutex);
+		return ret;
+	}
+
+	stream->ctrl = probe;
+	stream->cur_frame = frame;
+	mutex_unlock(&stream->mutex);
+
+	/* Return the actual frame period. */
+	timeperframe.numerator = probe.dwFrameInterval;
+	timeperframe.denominator = 10000000;
+	v4l2_simplify_fraction(&timeperframe.numerator,
+		&timeperframe.denominator, 8, 333);
+
+	if (parm->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+		parm->parm.capture.timeperframe = timeperframe;
+		parm->parm.capture.capability = V4L2_CAP_TIMEPERFRAME;
+	} else {
+		parm->parm.output.timeperframe = timeperframe;
+		parm->parm.output.capability = V4L2_CAP_TIMEPERFRAME;
+	}
+
+	return 0;
+}
+
+/* ------------------------------------------------------------------------
+ * Privilege management
+ */
+
+/*
+ * Privilege management is the multiple-open implementation basis. The current
+ * implementation is completely transparent for the end-user and doesn't
+ * require explicit use of the VIDIOC_G_PRIORITY and VIDIOC_S_PRIORITY ioctls.
+ * Those ioctls enable finer control on the device (by making possible for a
+ * user to request exclusive access to a device), but are not mature yet.
+ * Switching to the V4L2 priority mechanism might be considered in the future
+ * if this situation changes.
+ *
+ * Each open instance of a UVC device can either be in a privileged or
+ * unprivileged state. Only a single instance can be in a privileged state at
+ * a given time. Trying to perform an operation that requires privileges will
+ * automatically acquire the required privileges if possible, or return -EBUSY
+ * otherwise. Privileges are dismissed when closing the instance or when
+ * freeing the video buffers using VIDIOC_REQBUFS.
+ *
+ * Operations that require privileges are:
+ *
+ * - VIDIOC_S_INPUT
+ * - VIDIOC_S_PARM
+ * - VIDIOC_S_FMT
+ * - VIDIOC_REQBUFS
+ */
+static int uvc_acquire_privileges(struct uvc_fh *handle)
+{
+	/* Always succeed if the handle is already privileged. */
+	if (handle->state == UVC_HANDLE_ACTIVE)
+		return 0;
+
+	/* Check if the device already has a privileged handle. */
+	if (atomic_inc_return(&handle->stream->active) != 1) {
+		atomic_dec(&handle->stream->active);
+		return -EBUSY;
+	}
+
+	handle->state = UVC_HANDLE_ACTIVE;
+	return 0;
+}
+
+static void uvc_dismiss_privileges(struct uvc_fh *handle)
+{
+	if (handle->state == UVC_HANDLE_ACTIVE)
+		atomic_dec(&handle->stream->active);
+
+	handle->state = UVC_HANDLE_PASSIVE;
+}
+
+static int uvc_has_privileges(struct uvc_fh *handle)
+{
+	return handle->state == UVC_HANDLE_ACTIVE;
+}
+
+/* ------------------------------------------------------------------------
+ * V4L2 file operations
+ */
+
+static int uvc_v4l2_open(struct file *file)
+{
+	struct uvc_streaming *stream;
+	struct uvc_fh *handle;
+	int ret = 0;
+
+	stream = video_drvdata(file);
+	uvc_dbg(stream->dev, CALLS, "%s\n", __func__);
+
+	ret = usb_autopm_get_interface(stream->dev->intf);
+	if (ret < 0)
+		return ret;
+
+	/* Create the device handle. */
+	handle = kzalloc(sizeof(*handle), GFP_KERNEL);
+	if (handle == NULL) {
+		usb_autopm_put_interface(stream->dev->intf);
+		return -ENOMEM;
+	}
+
+	mutex_lock(&stream->dev->lock);
+	if (stream->dev->users == 0) {
+		ret = uvc_status_start(stream->dev, GFP_KERNEL);
+		if (ret < 0) {
+			mutex_unlock(&stream->dev->lock);
+			usb_autopm_put_interface(stream->dev->intf);
+			kfree(handle);
+			return ret;
+		}
+	}
+
+	stream->dev->users++;
+	mutex_unlock(&stream->dev->lock);
+
+	v4l2_fh_init(&handle->vfh, &stream->vdev);
+	v4l2_fh_add(&handle->vfh);
+	handle->chain = stream->chain;
+	handle->stream = stream;
+	handle->state = UVC_HANDLE_PASSIVE;
+	file->private_data = handle;
+
+	return 0;
+}
+
+static int uvc_v4l2_release(struct file *file)
+{
+	struct uvc_fh *handle = file->private_data;
+	struct uvc_streaming *stream = handle->stream;
+
+	uvc_dbg(stream->dev, CALLS, "%s\n", __func__);
+
+	/* Only free resources if this is a privileged handle. */
+	if (uvc_has_privileges(handle))
+		uvc_queue_release(&stream->queue);
+
+	/* Release the file handle. */
+	uvc_dismiss_privileges(handle);
+	v4l2_fh_del(&handle->vfh);
+	v4l2_fh_exit(&handle->vfh);
+	kfree(handle);
+	file->private_data = NULL;
+
+	mutex_lock(&stream->dev->lock);
+	if (--stream->dev->users == 0)
+		uvc_status_stop(stream->dev);
+	mutex_unlock(&stream->dev->lock);
+
+	usb_autopm_put_interface(stream->dev->intf);
+	return 0;
+}
+
+static int uvc_ioctl_querycap(struct file *file, void *fh,
+			      struct v4l2_capability *cap)
+{
+	struct uvc_fh *handle = file->private_data;
+	struct uvc_video_chain *chain = handle->chain;
+	struct uvc_streaming *stream = handle->stream;
+
+	strscpy(cap->driver, "uvcvideo", sizeof(cap->driver));
+	strscpy(cap->card, handle->stream->dev->name, sizeof(cap->card));
+	usb_make_path(stream->dev->udev, cap->bus_info, sizeof(cap->bus_info));
+	cap->capabilities = V4L2_CAP_DEVICE_CAPS | V4L2_CAP_STREAMING
+			  | chain->caps;
+
+	return 0;
+}
+
+static int uvc_ioctl_enum_fmt(struct uvc_streaming *stream,
+			      struct v4l2_fmtdesc *fmt)
+{
+	const struct uvc_format *format;
+	enum v4l2_buf_type type = fmt->type;
+	u32 index = fmt->index;
+
+	if (fmt->type != stream->type || fmt->index >= stream->nformats)
+		return -EINVAL;
+
+	memset(fmt, 0, sizeof(*fmt));
+	fmt->index = index;
+	fmt->type = type;
+
+	format = &stream->formats[fmt->index];
+	fmt->flags = 0;
+	if (format->flags & UVC_FMT_FLAG_COMPRESSED)
+		fmt->flags |= V4L2_FMT_FLAG_COMPRESSED;
+	fmt->pixelformat = format->fcc;
+	return 0;
+}
+
+static int uvc_ioctl_enum_fmt_vid_cap(struct file *file, void *fh,
+				      struct v4l2_fmtdesc *fmt)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+
+	return uvc_ioctl_enum_fmt(stream, fmt);
+}
+
+static int uvc_ioctl_enum_fmt_vid_out(struct file *file, void *fh,
+				      struct v4l2_fmtdesc *fmt)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+
+	return uvc_ioctl_enum_fmt(stream, fmt);
+}
+
+static int uvc_ioctl_g_fmt_vid_cap(struct file *file, void *fh,
+				   struct v4l2_format *fmt)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+
+	return uvc_v4l2_get_format(stream, fmt);
+}
+
+static int uvc_ioctl_g_fmt_vid_out(struct file *file, void *fh,
+				   struct v4l2_format *fmt)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+
+	return uvc_v4l2_get_format(stream, fmt);
+}
+
+static int uvc_ioctl_s_fmt_vid_cap(struct file *file, void *fh,
+				   struct v4l2_format *fmt)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+	int ret;
+
+	ret = uvc_acquire_privileges(handle);
+	if (ret < 0)
+		return ret;
+
+	return uvc_v4l2_set_format(stream, fmt);
+}
+
+static int uvc_ioctl_s_fmt_vid_out(struct file *file, void *fh,
+				   struct v4l2_format *fmt)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+	int ret;
+
+	ret = uvc_acquire_privileges(handle);
+	if (ret < 0)
+		return ret;
+
+	return uvc_v4l2_set_format(stream, fmt);
+}
+
+static int uvc_ioctl_try_fmt_vid_cap(struct file *file, void *fh,
+				     struct v4l2_format *fmt)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+	struct uvc_streaming_control probe;
+
+	return uvc_v4l2_try_format(stream, fmt, &probe, NULL, NULL);
+}
+
+static int uvc_ioctl_try_fmt_vid_out(struct file *file, void *fh,
+				     struct v4l2_format *fmt)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+	struct uvc_streaming_control probe;
+
+	return uvc_v4l2_try_format(stream, fmt, &probe, NULL, NULL);
+}
+
+static int uvc_ioctl_reqbufs(struct file *file, void *fh,
+			     struct v4l2_requestbuffers *rb)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+	int ret;
+
+	ret = uvc_acquire_privileges(handle);
+	if (ret < 0)
+		return ret;
+
+	mutex_lock(&stream->mutex);
+	ret = uvc_request_buffers(&stream->queue, rb);
+	mutex_unlock(&stream->mutex);
+	if (ret < 0)
+		return ret;
+
+	if (ret == 0)
+		uvc_dismiss_privileges(handle);
+
+	return 0;
+}
+
+static int uvc_ioctl_querybuf(struct file *file, void *fh,
+			      struct v4l2_buffer *buf)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+
+	if (!uvc_has_privileges(handle))
+		return -EBUSY;
+
+	return uvc_query_buffer(&stream->queue, buf);
+}
+
+static int uvc_ioctl_qbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+
+	if (!uvc_has_privileges(handle))
+		return -EBUSY;
+
+	return uvc_queue_buffer(&stream->queue,
+				stream->vdev.v4l2_dev->mdev, buf);
+}
+
+static int uvc_ioctl_expbuf(struct file *file, void *fh,
+			    struct v4l2_exportbuffer *exp)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+
+	if (!uvc_has_privileges(handle))
+		return -EBUSY;
+
+	return uvc_export_buffer(&stream->queue, exp);
+}
+
+static int uvc_ioctl_dqbuf(struct file *file, void *fh, struct v4l2_buffer *buf)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+
+	if (!uvc_has_privileges(handle))
+		return -EBUSY;
+
+	return uvc_dequeue_buffer(&stream->queue, buf,
+				  file->f_flags & O_NONBLOCK);
+}
+
+static int uvc_ioctl_create_bufs(struct file *file, void *fh,
+				  struct v4l2_create_buffers *cb)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+	int ret;
+
+	ret = uvc_acquire_privileges(handle);
+	if (ret < 0)
+		return ret;
+
+	return uvc_create_buffers(&stream->queue, cb);
+}
+
+static int uvc_ioctl_streamon(struct file *file, void *fh,
+			      enum v4l2_buf_type type)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+	int ret;
+
+	if (!uvc_has_privileges(handle))
+		return -EBUSY;
+
+	mutex_lock(&stream->mutex);
+	ret = uvc_queue_streamon(&stream->queue, type);
+	mutex_unlock(&stream->mutex);
+
+	return ret;
+}
+
+static int uvc_ioctl_streamoff(struct file *file, void *fh,
+			       enum v4l2_buf_type type)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+
+	if (!uvc_has_privileges(handle))
+		return -EBUSY;
+
+	mutex_lock(&stream->mutex);
+	uvc_queue_streamoff(&stream->queue, type);
+	mutex_unlock(&stream->mutex);
+
+	return 0;
+}
+
+static int uvc_ioctl_enum_input(struct file *file, void *fh,
+				struct v4l2_input *input)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_video_chain *chain = handle->chain;
+	const struct uvc_entity *selector = chain->selector;
+	struct uvc_entity *iterm = NULL;
+	struct uvc_entity *it;
+	u32 index = input->index;
+
+	if (selector == NULL ||
+	    (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
+		if (index != 0)
+			return -EINVAL;
+		list_for_each_entry(it, &chain->entities, chain) {
+			if (UVC_ENTITY_IS_ITERM(it)) {
+				iterm = it;
+				break;
+			}
+		}
+	} else if (index < selector->bNrInPins) {
+		list_for_each_entry(it, &chain->entities, chain) {
+			if (!UVC_ENTITY_IS_ITERM(it))
+				continue;
+			if (it->id == selector->baSourceID[index]) {
+				iterm = it;
+				break;
+			}
+		}
+	}
+
+	if (iterm == NULL)
+		return -EINVAL;
+
+	memset(input, 0, sizeof(*input));
+	input->index = index;
+	strscpy(input->name, iterm->name, sizeof(input->name));
+	if (UVC_ENTITY_TYPE(iterm) == UVC_ITT_CAMERA)
+		input->type = V4L2_INPUT_TYPE_CAMERA;
+
+	return 0;
+}
+
+static int uvc_ioctl_g_input(struct file *file, void *fh, unsigned int *input)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_video_chain *chain = handle->chain;
+	u8 *buf;
+	int ret;
+
+	if (chain->selector == NULL ||
+	    (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
+		*input = 0;
+		return 0;
+	}
+
+	buf = kmalloc(1, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR, chain->selector->id,
+			     chain->dev->intfnum,  UVC_SU_INPUT_SELECT_CONTROL,
+			     buf, 1);
+	if (!ret)
+		*input = *buf - 1;
+
+	kfree(buf);
+
+	return ret;
+}
+
+static int uvc_ioctl_s_input(struct file *file, void *fh, unsigned int input)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_video_chain *chain = handle->chain;
+	u8 *buf;
+	int ret;
+
+	ret = uvc_acquire_privileges(handle);
+	if (ret < 0)
+		return ret;
+
+	if (chain->selector == NULL ||
+	    (chain->dev->quirks & UVC_QUIRK_IGNORE_SELECTOR_UNIT)) {
+		if (input)
+			return -EINVAL;
+		return 0;
+	}
+
+	if (input >= chain->selector->bNrInPins)
+		return -EINVAL;
+
+	buf = kmalloc(1, GFP_KERNEL);
+	if (!buf)
+		return -ENOMEM;
+
+	*buf = input + 1;
+	ret = uvc_query_ctrl(chain->dev, UVC_SET_CUR, chain->selector->id,
+			     chain->dev->intfnum, UVC_SU_INPUT_SELECT_CONTROL,
+			     buf, 1);
+	kfree(buf);
+
+	return ret;
+}
+
+static int uvc_ioctl_queryctrl(struct file *file, void *fh,
+			       struct v4l2_queryctrl *qc)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_video_chain *chain = handle->chain;
+
+	return uvc_query_v4l2_ctrl(chain, qc);
+}
+
+static int uvc_ioctl_query_ext_ctrl(struct file *file, void *fh,
+				    struct v4l2_query_ext_ctrl *qec)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_video_chain *chain = handle->chain;
+	struct v4l2_queryctrl qc = { qec->id };
+	int ret;
+
+	ret = uvc_query_v4l2_ctrl(chain, &qc);
+	if (ret)
+		return ret;
+
+	qec->id = qc.id;
+	qec->type = qc.type;
+	strscpy(qec->name, qc.name, sizeof(qec->name));
+	qec->minimum = qc.minimum;
+	qec->maximum = qc.maximum;
+	qec->step = qc.step;
+	qec->default_value = qc.default_value;
+	qec->flags = qc.flags;
+	qec->elem_size = 4;
+	qec->elems = 1;
+	qec->nr_of_dims = 0;
+	memset(qec->dims, 0, sizeof(qec->dims));
+	memset(qec->reserved, 0, sizeof(qec->reserved));
+
+	return 0;
+}
+
+static int uvc_ctrl_check_access(struct uvc_video_chain *chain,
+				 struct v4l2_ext_controls *ctrls,
+				 unsigned long ioctl)
+{
+	struct v4l2_ext_control *ctrl = ctrls->controls;
+	unsigned int i;
+	int ret = 0;
+
+	for (i = 0; i < ctrls->count; ++ctrl, ++i) {
+		ret = uvc_ctrl_is_accessible(chain, ctrl->id, ctrls, ioctl);
+		if (ret)
+			break;
+	}
+
+	ctrls->error_idx = ioctl == VIDIOC_TRY_EXT_CTRLS ? i : ctrls->count;
+
+	return ret;
+}
+
+static int uvc_ioctl_g_ext_ctrls(struct file *file, void *fh,
+				 struct v4l2_ext_controls *ctrls)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_video_chain *chain = handle->chain;
+	struct v4l2_ext_control *ctrl = ctrls->controls;
+	unsigned int i;
+	int ret;
+
+	ret = uvc_ctrl_check_access(chain, ctrls, VIDIOC_G_EXT_CTRLS);
+	if (ret < 0)
+		return ret;
+
+	if (ctrls->which == V4L2_CTRL_WHICH_DEF_VAL) {
+		for (i = 0; i < ctrls->count; ++ctrl, ++i) {
+			struct v4l2_queryctrl qc = { .id = ctrl->id };
+
+			ret = uvc_query_v4l2_ctrl(chain, &qc);
+			if (ret < 0) {
+				ctrls->error_idx = i;
+				return ret;
+			}
+
+			ctrl->value = qc.default_value;
+		}
+
+		return 0;
+	}
+
+	ret = uvc_ctrl_begin(chain);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < ctrls->count; ++ctrl, ++i) {
+		ret = uvc_ctrl_get(chain, ctrl);
+		if (ret < 0) {
+			uvc_ctrl_rollback(handle);
+			ctrls->error_idx = i;
+			return ret;
+		}
+	}
+
+	ctrls->error_idx = 0;
+
+	return uvc_ctrl_rollback(handle);
+}
+
+static int uvc_ioctl_s_try_ext_ctrls(struct uvc_fh *handle,
+				     struct v4l2_ext_controls *ctrls,
+				     unsigned long ioctl)
+{
+	struct v4l2_ext_control *ctrl = ctrls->controls;
+	struct uvc_video_chain *chain = handle->chain;
+	unsigned int i;
+	int ret;
+
+	ret = uvc_ctrl_check_access(chain, ctrls, ioctl);
+	if (ret < 0)
+		return ret;
+
+	ret = uvc_ctrl_begin(chain);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < ctrls->count; ++ctrl, ++i) {
+		ret = uvc_ctrl_set(handle, ctrl);
+		if (ret < 0) {
+			uvc_ctrl_rollback(handle);
+			ctrls->error_idx = ioctl == VIDIOC_S_EXT_CTRLS ?
+						    ctrls->count : i;
+			return ret;
+		}
+	}
+
+	ctrls->error_idx = 0;
+
+	if (ioctl == VIDIOC_S_EXT_CTRLS)
+		return uvc_ctrl_commit(handle, ctrls);
+	else
+		return uvc_ctrl_rollback(handle);
+}
+
+static int uvc_ioctl_s_ext_ctrls(struct file *file, void *fh,
+				 struct v4l2_ext_controls *ctrls)
+{
+	struct uvc_fh *handle = fh;
+
+	return uvc_ioctl_s_try_ext_ctrls(handle, ctrls, VIDIOC_S_EXT_CTRLS);
+}
+
+static int uvc_ioctl_try_ext_ctrls(struct file *file, void *fh,
+				   struct v4l2_ext_controls *ctrls)
+{
+	struct uvc_fh *handle = fh;
+
+	return uvc_ioctl_s_try_ext_ctrls(handle, ctrls, VIDIOC_TRY_EXT_CTRLS);
+}
+
+static int uvc_ioctl_querymenu(struct file *file, void *fh,
+			       struct v4l2_querymenu *qm)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_video_chain *chain = handle->chain;
+
+	return uvc_query_v4l2_menu(chain, qm);
+}
+
+static int uvc_ioctl_g_selection(struct file *file, void *fh,
+				 struct v4l2_selection *sel)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+
+	if (sel->type != stream->type)
+		return -EINVAL;
+
+	switch (sel->target) {
+	case V4L2_SEL_TGT_CROP_DEFAULT:
+	case V4L2_SEL_TGT_CROP_BOUNDS:
+		if (stream->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
+			return -EINVAL;
+		break;
+	case V4L2_SEL_TGT_COMPOSE_DEFAULT:
+	case V4L2_SEL_TGT_COMPOSE_BOUNDS:
+		if (stream->type != V4L2_BUF_TYPE_VIDEO_OUTPUT)
+			return -EINVAL;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	sel->r.left = 0;
+	sel->r.top = 0;
+	mutex_lock(&stream->mutex);
+	sel->r.width = stream->cur_frame->wWidth;
+	sel->r.height = stream->cur_frame->wHeight;
+	mutex_unlock(&stream->mutex);
+
+	return 0;
+}
+
+static int uvc_ioctl_g_parm(struct file *file, void *fh,
+			    struct v4l2_streamparm *parm)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+
+	return uvc_v4l2_get_streamparm(stream, parm);
+}
+
+static int uvc_ioctl_s_parm(struct file *file, void *fh,
+			    struct v4l2_streamparm *parm)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+	int ret;
+
+	ret = uvc_acquire_privileges(handle);
+	if (ret < 0)
+		return ret;
+
+	return uvc_v4l2_set_streamparm(stream, parm);
+}
+
+static int uvc_ioctl_enum_framesizes(struct file *file, void *fh,
+				     struct v4l2_frmsizeenum *fsize)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+	const struct uvc_format *format = NULL;
+	const struct uvc_frame *frame = NULL;
+	unsigned int index;
+	unsigned int i;
+
+	/* Look for the given pixel format */
+	for (i = 0; i < stream->nformats; i++) {
+		if (stream->formats[i].fcc == fsize->pixel_format) {
+			format = &stream->formats[i];
+			break;
+		}
+	}
+	if (format == NULL)
+		return -EINVAL;
+
+	/* Skip duplicate frame sizes */
+	for (i = 0, index = 0; i < format->nframes; i++) {
+		if (frame && frame->wWidth == format->frames[i].wWidth &&
+		    frame->wHeight == format->frames[i].wHeight)
+			continue;
+		frame = &format->frames[i];
+		if (index == fsize->index)
+			break;
+		index++;
+	}
+
+	if (i == format->nframes)
+		return -EINVAL;
+
+	fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
+	fsize->discrete.width = frame->wWidth;
+	fsize->discrete.height = frame->wHeight;
+	return 0;
+}
+
+static int uvc_ioctl_enum_frameintervals(struct file *file, void *fh,
+					 struct v4l2_frmivalenum *fival)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_streaming *stream = handle->stream;
+	const struct uvc_format *format = NULL;
+	const struct uvc_frame *frame = NULL;
+	unsigned int nintervals;
+	unsigned int index;
+	unsigned int i;
+
+	/* Look for the given pixel format and frame size */
+	for (i = 0; i < stream->nformats; i++) {
+		if (stream->formats[i].fcc == fival->pixel_format) {
+			format = &stream->formats[i];
+			break;
+		}
+	}
+	if (format == NULL)
+		return -EINVAL;
+
+	index = fival->index;
+	for (i = 0; i < format->nframes; i++) {
+		if (format->frames[i].wWidth == fival->width &&
+		    format->frames[i].wHeight == fival->height) {
+			frame = &format->frames[i];
+			nintervals = frame->bFrameIntervalType ?: 1;
+			if (index < nintervals)
+				break;
+			index -= nintervals;
+		}
+	}
+	if (i == format->nframes)
+		return -EINVAL;
+
+	if (frame->bFrameIntervalType) {
+		fival->type = V4L2_FRMIVAL_TYPE_DISCRETE;
+		fival->discrete.numerator =
+			frame->dwFrameInterval[index];
+		fival->discrete.denominator = 10000000;
+		v4l2_simplify_fraction(&fival->discrete.numerator,
+			&fival->discrete.denominator, 8, 333);
+	} else {
+		fival->type = V4L2_FRMIVAL_TYPE_STEPWISE;
+		fival->stepwise.min.numerator = frame->dwFrameInterval[0];
+		fival->stepwise.min.denominator = 10000000;
+		fival->stepwise.max.numerator = frame->dwFrameInterval[1];
+		fival->stepwise.max.denominator = 10000000;
+		fival->stepwise.step.numerator = frame->dwFrameInterval[2];
+		fival->stepwise.step.denominator = 10000000;
+		v4l2_simplify_fraction(&fival->stepwise.min.numerator,
+			&fival->stepwise.min.denominator, 8, 333);
+		v4l2_simplify_fraction(&fival->stepwise.max.numerator,
+			&fival->stepwise.max.denominator, 8, 333);
+		v4l2_simplify_fraction(&fival->stepwise.step.numerator,
+			&fival->stepwise.step.denominator, 8, 333);
+	}
+
+	return 0;
+}
+
+static int uvc_ioctl_subscribe_event(struct v4l2_fh *fh,
+				     const struct v4l2_event_subscription *sub)
+{
+	switch (sub->type) {
+	case V4L2_EVENT_CTRL:
+		return v4l2_event_subscribe(fh, sub, 0, &uvc_ctrl_sub_ev_ops);
+	default:
+		return -EINVAL;
+	}
+}
+
+static long uvc_ioctl_default(struct file *file, void *fh, bool valid_prio,
+			      unsigned int cmd, void *arg)
+{
+	struct uvc_fh *handle = fh;
+	struct uvc_video_chain *chain = handle->chain;
+
+	switch (cmd) {
+	/* Dynamic controls. */
+	case UVCIOC_CTRL_MAP:
+		return uvc_ioctl_xu_ctrl_map(chain, arg);
+
+	case UVCIOC_CTRL_QUERY:
+		return uvc_xu_ctrl_query(chain, arg);
+
+	default:
+		return -ENOTTY;
+	}
+}
+
+#ifdef CONFIG_COMPAT
+struct uvc_xu_control_mapping32 {
+	u32 id;
+	u8 name[32];
+	u8 entity[16];
+	u8 selector;
+
+	u8 size;
+	u8 offset;
+	u32 v4l2_type;
+	u32 data_type;
+
+	compat_caddr_t menu_info;
+	u32 menu_count;
+
+	u32 reserved[4];
+};
+
+static int uvc_v4l2_get_xu_mapping(struct uvc_xu_control_mapping *kp,
+			const struct uvc_xu_control_mapping32 __user *up)
+{
+	struct uvc_xu_control_mapping32 *p = (void *)kp;
+	compat_caddr_t info;
+	u32 count;
+
+	if (copy_from_user(p, up, sizeof(*p)))
+		return -EFAULT;
+
+	count = p->menu_count;
+	info = p->menu_info;
+
+	memset(kp->reserved, 0, sizeof(kp->reserved));
+	kp->menu_info = count ? compat_ptr(info) : NULL;
+	kp->menu_count = count;
+	return 0;
+}
+
+static int uvc_v4l2_put_xu_mapping(const struct uvc_xu_control_mapping *kp,
+			struct uvc_xu_control_mapping32 __user *up)
+{
+	if (copy_to_user(up, kp, offsetof(typeof(*up), menu_info)) ||
+	    put_user(kp->menu_count, &up->menu_count))
+		return -EFAULT;
+
+	if (clear_user(up->reserved, sizeof(up->reserved)))
+		return -EFAULT;
+
+	return 0;
+}
+
+struct uvc_xu_control_query32 {
+	u8 unit;
+	u8 selector;
+	u8 query;
+	u16 size;
+	compat_caddr_t data;
+};
+
+static int uvc_v4l2_get_xu_query(struct uvc_xu_control_query *kp,
+			const struct uvc_xu_control_query32 __user *up)
+{
+	struct uvc_xu_control_query32 v;
+
+	if (copy_from_user(&v, up, sizeof(v)))
+		return -EFAULT;
+
+	*kp = (struct uvc_xu_control_query){
+		.unit = v.unit,
+		.selector = v.selector,
+		.query = v.query,
+		.size = v.size,
+		.data = v.size ? compat_ptr(v.data) : NULL
+	};
+	return 0;
+}
+
+static int uvc_v4l2_put_xu_query(const struct uvc_xu_control_query *kp,
+			struct uvc_xu_control_query32 __user *up)
+{
+	if (copy_to_user(up, kp, offsetof(typeof(*up), data)))
+		return -EFAULT;
+	return 0;
+}
+
+#define UVCIOC_CTRL_MAP32	_IOWR('u', 0x20, struct uvc_xu_control_mapping32)
+#define UVCIOC_CTRL_QUERY32	_IOWR('u', 0x21, struct uvc_xu_control_query32)
+
+static long uvc_v4l2_compat_ioctl32(struct file *file,
+		     unsigned int cmd, unsigned long arg)
+{
+	struct uvc_fh *handle = file->private_data;
+	union {
+		struct uvc_xu_control_mapping xmap;
+		struct uvc_xu_control_query xqry;
+	} karg;
+	void __user *up = compat_ptr(arg);
+	long ret;
+
+	switch (cmd) {
+	case UVCIOC_CTRL_MAP32:
+		ret = uvc_v4l2_get_xu_mapping(&karg.xmap, up);
+		if (ret)
+			return ret;
+		ret = uvc_ioctl_xu_ctrl_map(handle->chain, &karg.xmap);
+		if (ret)
+			return ret;
+		ret = uvc_v4l2_put_xu_mapping(&karg.xmap, up);
+		if (ret)
+			return ret;
+
+		break;
+
+	case UVCIOC_CTRL_QUERY32:
+		ret = uvc_v4l2_get_xu_query(&karg.xqry, up);
+		if (ret)
+			return ret;
+		ret = uvc_xu_ctrl_query(handle->chain, &karg.xqry);
+		if (ret)
+			return ret;
+		ret = uvc_v4l2_put_xu_query(&karg.xqry, up);
+		if (ret)
+			return ret;
+		break;
+
+	default:
+		return -ENOIOCTLCMD;
+	}
+
+	return ret;
+}
+#endif
+
+static ssize_t uvc_v4l2_read(struct file *file, char __user *data,
+		    size_t count, loff_t *ppos)
+{
+	struct uvc_fh *handle = file->private_data;
+	struct uvc_streaming *stream = handle->stream;
+
+	uvc_dbg(stream->dev, CALLS, "%s: not implemented\n", __func__);
+	return -EINVAL;
+}
+
+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;
+
+	uvc_dbg(stream->dev, CALLS, "%s\n", __func__);
+
+	return uvc_queue_mmap(&stream->queue, vma);
+}
+
+static __poll_t uvc_v4l2_poll(struct file *file, poll_table *wait)
+{
+	struct uvc_fh *handle = file->private_data;
+	struct uvc_streaming *stream = handle->stream;
+
+	uvc_dbg(stream->dev, CALLS, "%s\n", __func__);
+
+	return uvc_queue_poll(&stream->queue, file, wait);
+}
+
+#ifndef CONFIG_MMU
+static unsigned long uvc_v4l2_get_unmapped_area(struct file *file,
+		unsigned long addr, unsigned long len, unsigned long pgoff,
+		unsigned long flags)
+{
+	struct uvc_fh *handle = file->private_data;
+	struct uvc_streaming *stream = handle->stream;
+
+	uvc_dbg(stream->dev, CALLS, "%s\n", __func__);
+
+	return uvc_queue_get_unmapped_area(&stream->queue, pgoff);
+}
+#endif
+
+const struct v4l2_ioctl_ops uvc_ioctl_ops = {
+	.vidioc_querycap = uvc_ioctl_querycap,
+	.vidioc_enum_fmt_vid_cap = uvc_ioctl_enum_fmt_vid_cap,
+	.vidioc_enum_fmt_vid_out = uvc_ioctl_enum_fmt_vid_out,
+	.vidioc_g_fmt_vid_cap = uvc_ioctl_g_fmt_vid_cap,
+	.vidioc_g_fmt_vid_out = uvc_ioctl_g_fmt_vid_out,
+	.vidioc_s_fmt_vid_cap = uvc_ioctl_s_fmt_vid_cap,
+	.vidioc_s_fmt_vid_out = uvc_ioctl_s_fmt_vid_out,
+	.vidioc_try_fmt_vid_cap = uvc_ioctl_try_fmt_vid_cap,
+	.vidioc_try_fmt_vid_out = uvc_ioctl_try_fmt_vid_out,
+	.vidioc_reqbufs = uvc_ioctl_reqbufs,
+	.vidioc_querybuf = uvc_ioctl_querybuf,
+	.vidioc_qbuf = uvc_ioctl_qbuf,
+	.vidioc_expbuf = uvc_ioctl_expbuf,
+	.vidioc_dqbuf = uvc_ioctl_dqbuf,
+	.vidioc_create_bufs = uvc_ioctl_create_bufs,
+	.vidioc_streamon = uvc_ioctl_streamon,
+	.vidioc_streamoff = uvc_ioctl_streamoff,
+	.vidioc_enum_input = uvc_ioctl_enum_input,
+	.vidioc_g_input = uvc_ioctl_g_input,
+	.vidioc_s_input = uvc_ioctl_s_input,
+	.vidioc_queryctrl = uvc_ioctl_queryctrl,
+	.vidioc_query_ext_ctrl = uvc_ioctl_query_ext_ctrl,
+	.vidioc_g_ext_ctrls = uvc_ioctl_g_ext_ctrls,
+	.vidioc_s_ext_ctrls = uvc_ioctl_s_ext_ctrls,
+	.vidioc_try_ext_ctrls = uvc_ioctl_try_ext_ctrls,
+	.vidioc_querymenu = uvc_ioctl_querymenu,
+	.vidioc_g_selection = uvc_ioctl_g_selection,
+	.vidioc_g_parm = uvc_ioctl_g_parm,
+	.vidioc_s_parm = uvc_ioctl_s_parm,
+	.vidioc_enum_framesizes = uvc_ioctl_enum_framesizes,
+	.vidioc_enum_frameintervals = uvc_ioctl_enum_frameintervals,
+	.vidioc_subscribe_event = uvc_ioctl_subscribe_event,
+	.vidioc_unsubscribe_event = v4l2_event_unsubscribe,
+	.vidioc_default = uvc_ioctl_default,
+};
+
+const struct v4l2_file_operations uvc_fops = {
+	.owner		= THIS_MODULE,
+	.open		= uvc_v4l2_open,
+	.release	= uvc_v4l2_release,
+	.unlocked_ioctl	= video_ioctl2,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl32	= uvc_v4l2_compat_ioctl32,
+#endif
+	.read		= uvc_v4l2_read,
+	.mmap		= uvc_v4l2_mmap,
+	.poll		= uvc_v4l2_poll,
+#ifndef CONFIG_MMU
+	.get_unmapped_area = uvc_v4l2_get_unmapped_area,
+#endif
+};
+
diff --git a/drivers/media/usb/uvc/uvc_video.c b/drivers/media/usb/uvc/uvc_video.c
new file mode 100644
index 000000000..28dde08ec
--- /dev/null
+++ b/drivers/media/usb/uvc/uvc_video.c
@@ -0,0 +1,2270 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *      uvc_video.c  --  USB Video Class driver - Video handling
+ *
+ *      Copyright (C) 2005-2010
+ *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ */
+
+#include <linux/dma-mapping.h>
+#include <linux/highmem.h>
+#include <linux/kernel.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+#include <linux/videodev2.h>
+#include <linux/vmalloc.h>
+#include <linux/wait.h>
+#include <linux/atomic.h>
+#include <asm/unaligned.h>
+
+#include <media/v4l2-common.h>
+
+#include "uvcvideo.h"
+
+/* ------------------------------------------------------------------------
+ * UVC Controls
+ */
+
+static int __uvc_query_ctrl(struct uvc_device *dev, u8 query, u8 unit,
+			u8 intfnum, u8 cs, void *data, u16 size,
+			int timeout)
+{
+	u8 type = USB_TYPE_CLASS | USB_RECIP_INTERFACE;
+	unsigned int pipe;
+
+	pipe = (query & 0x80) ? usb_rcvctrlpipe(dev->udev, 0)
+			      : usb_sndctrlpipe(dev->udev, 0);
+	type |= (query & 0x80) ? USB_DIR_IN : USB_DIR_OUT;
+
+	return usb_control_msg(dev->udev, pipe, query, type, cs << 8,
+			unit << 8 | intfnum, data, size, timeout);
+}
+
+static const char *uvc_query_name(u8 query)
+{
+	switch (query) {
+	case UVC_SET_CUR:
+		return "SET_CUR";
+	case UVC_GET_CUR:
+		return "GET_CUR";
+	case UVC_GET_MIN:
+		return "GET_MIN";
+	case UVC_GET_MAX:
+		return "GET_MAX";
+	case UVC_GET_RES:
+		return "GET_RES";
+	case UVC_GET_LEN:
+		return "GET_LEN";
+	case UVC_GET_INFO:
+		return "GET_INFO";
+	case UVC_GET_DEF:
+		return "GET_DEF";
+	default:
+		return "<invalid>";
+	}
+}
+
+int uvc_query_ctrl(struct uvc_device *dev, u8 query, u8 unit,
+			u8 intfnum, u8 cs, void *data, u16 size)
+{
+	int ret;
+	u8 error;
+	u8 tmp;
+
+	ret = __uvc_query_ctrl(dev, query, unit, intfnum, cs, data, size,
+				UVC_CTRL_CONTROL_TIMEOUT);
+	if (likely(ret == size))
+		return 0;
+
+	if (ret != -EPIPE) {
+		dev_err(&dev->udev->dev,
+			"Failed to query (%s) UVC control %u on unit %u: %d (exp. %u).\n",
+			uvc_query_name(query), cs, unit, ret, size);
+		return ret < 0 ? ret : -EPIPE;
+	}
+
+	/* Reuse data[0] to request the error code. */
+	tmp = *(u8 *)data;
+
+	ret = __uvc_query_ctrl(dev, UVC_GET_CUR, 0, intfnum,
+			       UVC_VC_REQUEST_ERROR_CODE_CONTROL, data, 1,
+			       UVC_CTRL_CONTROL_TIMEOUT);
+
+	error = *(u8 *)data;
+	*(u8 *)data = tmp;
+
+	if (ret != 1)
+		return ret < 0 ? ret : -EPIPE;
+
+	uvc_dbg(dev, CONTROL, "Control error %u\n", error);
+
+	switch (error) {
+	case 0:
+		/* Cannot happen - we received a STALL */
+		return -EPIPE;
+	case 1: /* Not ready */
+		return -EBUSY;
+	case 2: /* Wrong state */
+		return -EACCES;
+	case 3: /* Power */
+		return -EREMOTE;
+	case 4: /* Out of range */
+		return -ERANGE;
+	case 5: /* Invalid unit */
+	case 6: /* Invalid control */
+	case 7: /* Invalid Request */
+		/*
+		 * The firmware has not properly implemented
+		 * the control or there has been a HW error.
+		 */
+		return -EIO;
+	case 8: /* Invalid value within range */
+		return -EINVAL;
+	default: /* reserved or unknown */
+		break;
+	}
+
+	return -EPIPE;
+}
+
+static const struct usb_device_id elgato_cam_link_4k = {
+	USB_DEVICE(0x0fd9, 0x0066)
+};
+
+static void uvc_fixup_video_ctrl(struct uvc_streaming *stream,
+	struct uvc_streaming_control *ctrl)
+{
+	const struct uvc_format *format = NULL;
+	const struct uvc_frame *frame = NULL;
+	unsigned int i;
+
+	/*
+	 * The response of the Elgato Cam Link 4K is incorrect: The second byte
+	 * contains bFormatIndex (instead of being the second byte of bmHint).
+	 * The first byte is always zero. The third byte is always 1.
+	 *
+	 * The UVC 1.5 class specification defines the first five bits in the
+	 * bmHint bitfield. The remaining bits are reserved and should be zero.
+	 * Therefore a valid bmHint will be less than 32.
+	 *
+	 * Latest Elgato Cam Link 4K firmware as of 2021-03-23 needs this fix.
+	 * MCU: 20.02.19, FPGA: 67
+	 */
+	if (usb_match_one_id(stream->dev->intf, &elgato_cam_link_4k) &&
+	    ctrl->bmHint > 255) {
+		u8 corrected_format_index = ctrl->bmHint >> 8;
+
+		uvc_dbg(stream->dev, VIDEO,
+			"Correct USB video probe response from {bmHint: 0x%04x, bFormatIndex: %u} to {bmHint: 0x%04x, bFormatIndex: %u}\n",
+			ctrl->bmHint, ctrl->bFormatIndex,
+			1, corrected_format_index);
+		ctrl->bmHint = 1;
+		ctrl->bFormatIndex = corrected_format_index;
+	}
+
+	for (i = 0; i < stream->nformats; ++i) {
+		if (stream->formats[i].index == ctrl->bFormatIndex) {
+			format = &stream->formats[i];
+			break;
+		}
+	}
+
+	if (format == NULL)
+		return;
+
+	for (i = 0; i < format->nframes; ++i) {
+		if (format->frames[i].bFrameIndex == ctrl->bFrameIndex) {
+			frame = &format->frames[i];
+			break;
+		}
+	}
+
+	if (frame == NULL)
+		return;
+
+	if (!(format->flags & UVC_FMT_FLAG_COMPRESSED) ||
+	     (ctrl->dwMaxVideoFrameSize == 0 &&
+	      stream->dev->uvc_version < 0x0110))
+		ctrl->dwMaxVideoFrameSize =
+			frame->dwMaxVideoFrameBufferSize;
+
+	/*
+	 * The "TOSHIBA Web Camera - 5M" Chicony device (04f2:b50b) seems to
+	 * compute the bandwidth on 16 bits and erroneously sign-extend it to
+	 * 32 bits, resulting in a huge bandwidth value. Detect and fix that
+	 * condition by setting the 16 MSBs to 0 when they're all equal to 1.
+	 */
+	if ((ctrl->dwMaxPayloadTransferSize & 0xffff0000) == 0xffff0000)
+		ctrl->dwMaxPayloadTransferSize &= ~0xffff0000;
+
+	if (!(format->flags & UVC_FMT_FLAG_COMPRESSED) &&
+	    stream->dev->quirks & UVC_QUIRK_FIX_BANDWIDTH &&
+	    stream->intf->num_altsetting > 1) {
+		u32 interval;
+		u32 bandwidth;
+
+		interval = (ctrl->dwFrameInterval > 100000)
+			 ? ctrl->dwFrameInterval
+			 : frame->dwFrameInterval[0];
+
+		/*
+		 * Compute a bandwidth estimation by multiplying the frame
+		 * size by the number of video frames per second, divide the
+		 * result by the number of USB frames (or micro-frames for
+		 * high-speed devices) per second and add the UVC header size
+		 * (assumed to be 12 bytes long).
+		 */
+		bandwidth = frame->wWidth * frame->wHeight / 8 * format->bpp;
+		bandwidth *= 10000000 / interval + 1;
+		bandwidth /= 1000;
+		if (stream->dev->udev->speed == USB_SPEED_HIGH)
+			bandwidth /= 8;
+		bandwidth += 12;
+
+		/*
+		 * The bandwidth estimate is too low for many cameras. Don't use
+		 * maximum packet sizes lower than 1024 bytes to try and work
+		 * around the problem. According to measurements done on two
+		 * different camera models, the value is high enough to get most
+		 * resolutions working while not preventing two simultaneous
+		 * VGA streams at 15 fps.
+		 */
+		bandwidth = max_t(u32, bandwidth, 1024);
+
+		ctrl->dwMaxPayloadTransferSize = bandwidth;
+	}
+}
+
+static size_t uvc_video_ctrl_size(struct uvc_streaming *stream)
+{
+	/*
+	 * Return the size of the video probe and commit controls, which depends
+	 * on the protocol version.
+	 */
+	if (stream->dev->uvc_version < 0x0110)
+		return 26;
+	else if (stream->dev->uvc_version < 0x0150)
+		return 34;
+	else
+		return 48;
+}
+
+static int uvc_get_video_ctrl(struct uvc_streaming *stream,
+	struct uvc_streaming_control *ctrl, int probe, u8 query)
+{
+	u16 size = uvc_video_ctrl_size(stream);
+	u8 *data;
+	int ret;
+
+	if ((stream->dev->quirks & UVC_QUIRK_PROBE_DEF) &&
+			query == UVC_GET_DEF)
+		return -EIO;
+
+	data = kmalloc(size, GFP_KERNEL);
+	if (data == NULL)
+		return -ENOMEM;
+
+	ret = __uvc_query_ctrl(stream->dev, query, 0, stream->intfnum,
+		probe ? UVC_VS_PROBE_CONTROL : UVC_VS_COMMIT_CONTROL, data,
+		size, uvc_timeout_param);
+
+	if ((query == UVC_GET_MIN || query == UVC_GET_MAX) && ret == 2) {
+		/*
+		 * Some cameras, mostly based on Bison Electronics chipsets,
+		 * answer a GET_MIN or GET_MAX request with the wCompQuality
+		 * field only.
+		 */
+		uvc_warn_once(stream->dev, UVC_WARN_MINMAX, "UVC non "
+			"compliance - GET_MIN/MAX(PROBE) incorrectly "
+			"supported. Enabling workaround.\n");
+		memset(ctrl, 0, sizeof(*ctrl));
+		ctrl->wCompQuality = le16_to_cpup((__le16 *)data);
+		ret = 0;
+		goto out;
+	} else if (query == UVC_GET_DEF && probe == 1 && ret != size) {
+		/*
+		 * Many cameras don't support the GET_DEF request on their
+		 * video probe control. Warn once and return, the caller will
+		 * fall back to GET_CUR.
+		 */
+		uvc_warn_once(stream->dev, UVC_WARN_PROBE_DEF, "UVC non "
+			"compliance - GET_DEF(PROBE) not supported. "
+			"Enabling workaround.\n");
+		ret = -EIO;
+		goto out;
+	} else if (ret != size) {
+		dev_err(&stream->intf->dev,
+			"Failed to query (%u) UVC %s control : %d (exp. %u).\n",
+			query, probe ? "probe" : "commit", ret, size);
+		ret = (ret == -EPROTO) ? -EPROTO : -EIO;
+		goto out;
+	}
+
+	ctrl->bmHint = le16_to_cpup((__le16 *)&data[0]);
+	ctrl->bFormatIndex = data[2];
+	ctrl->bFrameIndex = data[3];
+	ctrl->dwFrameInterval = le32_to_cpup((__le32 *)&data[4]);
+	ctrl->wKeyFrameRate = le16_to_cpup((__le16 *)&data[8]);
+	ctrl->wPFrameRate = le16_to_cpup((__le16 *)&data[10]);
+	ctrl->wCompQuality = le16_to_cpup((__le16 *)&data[12]);
+	ctrl->wCompWindowSize = le16_to_cpup((__le16 *)&data[14]);
+	ctrl->wDelay = le16_to_cpup((__le16 *)&data[16]);
+	ctrl->dwMaxVideoFrameSize = get_unaligned_le32(&data[18]);
+	ctrl->dwMaxPayloadTransferSize = get_unaligned_le32(&data[22]);
+
+	if (size >= 34) {
+		ctrl->dwClockFrequency = get_unaligned_le32(&data[26]);
+		ctrl->bmFramingInfo = data[30];
+		ctrl->bPreferedVersion = data[31];
+		ctrl->bMinVersion = data[32];
+		ctrl->bMaxVersion = data[33];
+	} else {
+		ctrl->dwClockFrequency = stream->dev->clock_frequency;
+		ctrl->bmFramingInfo = 0;
+		ctrl->bPreferedVersion = 0;
+		ctrl->bMinVersion = 0;
+		ctrl->bMaxVersion = 0;
+	}
+
+	/*
+	 * Some broken devices return null or wrong dwMaxVideoFrameSize and
+	 * dwMaxPayloadTransferSize fields. Try to get the value from the
+	 * format and frame descriptors.
+	 */
+	uvc_fixup_video_ctrl(stream, ctrl);
+	ret = 0;
+
+out:
+	kfree(data);
+	return ret;
+}
+
+static int uvc_set_video_ctrl(struct uvc_streaming *stream,
+	struct uvc_streaming_control *ctrl, int probe)
+{
+	u16 size = uvc_video_ctrl_size(stream);
+	u8 *data;
+	int ret;
+
+	data = kzalloc(size, GFP_KERNEL);
+	if (data == NULL)
+		return -ENOMEM;
+
+	*(__le16 *)&data[0] = cpu_to_le16(ctrl->bmHint);
+	data[2] = ctrl->bFormatIndex;
+	data[3] = ctrl->bFrameIndex;
+	*(__le32 *)&data[4] = cpu_to_le32(ctrl->dwFrameInterval);
+	*(__le16 *)&data[8] = cpu_to_le16(ctrl->wKeyFrameRate);
+	*(__le16 *)&data[10] = cpu_to_le16(ctrl->wPFrameRate);
+	*(__le16 *)&data[12] = cpu_to_le16(ctrl->wCompQuality);
+	*(__le16 *)&data[14] = cpu_to_le16(ctrl->wCompWindowSize);
+	*(__le16 *)&data[16] = cpu_to_le16(ctrl->wDelay);
+	put_unaligned_le32(ctrl->dwMaxVideoFrameSize, &data[18]);
+	put_unaligned_le32(ctrl->dwMaxPayloadTransferSize, &data[22]);
+
+	if (size >= 34) {
+		put_unaligned_le32(ctrl->dwClockFrequency, &data[26]);
+		data[30] = ctrl->bmFramingInfo;
+		data[31] = ctrl->bPreferedVersion;
+		data[32] = ctrl->bMinVersion;
+		data[33] = ctrl->bMaxVersion;
+	}
+
+	ret = __uvc_query_ctrl(stream->dev, UVC_SET_CUR, 0, stream->intfnum,
+		probe ? UVC_VS_PROBE_CONTROL : UVC_VS_COMMIT_CONTROL, data,
+		size, uvc_timeout_param);
+	if (ret != size) {
+		dev_err(&stream->intf->dev,
+			"Failed to set UVC %s control : %d (exp. %u).\n",
+			probe ? "probe" : "commit", ret, size);
+		ret = -EIO;
+	}
+
+	kfree(data);
+	return ret;
+}
+
+int uvc_probe_video(struct uvc_streaming *stream,
+	struct uvc_streaming_control *probe)
+{
+	struct uvc_streaming_control probe_min, probe_max;
+	unsigned int i;
+	int ret;
+
+	/*
+	 * 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
+	 * Probe control properly, and just return the needed bandwidth. For
+	 * that reason, if the needed bandwidth exceeds the maximum available
+	 * bandwidth, try to lower the quality.
+	 */
+	ret = uvc_set_video_ctrl(stream, probe, 1);
+	if (ret < 0)
+		goto done;
+
+	/* Get the minimum and maximum values for compression settings. */
+	if (!(stream->dev->quirks & UVC_QUIRK_PROBE_MINMAX)) {
+		ret = uvc_get_video_ctrl(stream, &probe_min, 1, UVC_GET_MIN);
+		if (ret < 0)
+			goto done;
+		ret = uvc_get_video_ctrl(stream, &probe_max, 1, UVC_GET_MAX);
+		if (ret < 0)
+			goto done;
+
+		probe->wCompQuality = probe_max.wCompQuality;
+	}
+
+	for (i = 0; i < 2; ++i) {
+		ret = uvc_set_video_ctrl(stream, probe, 1);
+		if (ret < 0)
+			goto done;
+		ret = uvc_get_video_ctrl(stream, probe, 1, UVC_GET_CUR);
+		if (ret < 0)
+			goto done;
+
+		if (stream->intf->num_altsetting == 1)
+			break;
+
+		if (probe->dwMaxPayloadTransferSize <= stream->maxpsize)
+			break;
+
+		if (stream->dev->quirks & UVC_QUIRK_PROBE_MINMAX) {
+			ret = -ENOSPC;
+			goto done;
+		}
+
+		/* TODO: negotiate compression parameters */
+		probe->wKeyFrameRate = probe_min.wKeyFrameRate;
+		probe->wPFrameRate = probe_min.wPFrameRate;
+		probe->wCompQuality = probe_max.wCompQuality;
+		probe->wCompWindowSize = probe_min.wCompWindowSize;
+	}
+
+done:
+	return ret;
+}
+
+static int uvc_commit_video(struct uvc_streaming *stream,
+			    struct uvc_streaming_control *probe)
+{
+	return uvc_set_video_ctrl(stream, probe, 0);
+}
+
+/* -----------------------------------------------------------------------------
+ * Clocks and timestamps
+ */
+
+static inline ktime_t uvc_video_get_time(void)
+{
+	if (uvc_clock_param == CLOCK_MONOTONIC)
+		return ktime_get();
+	else
+		return ktime_get_real();
+}
+
+static void
+uvc_video_clock_decode(struct uvc_streaming *stream, struct uvc_buffer *buf,
+		       const u8 *data, int len)
+{
+	struct uvc_clock_sample *sample;
+	unsigned int header_size;
+	bool has_pts = false;
+	bool has_scr = false;
+	unsigned long flags;
+	ktime_t time;
+	u16 host_sof;
+	u16 dev_sof;
+
+	switch (data[1] & (UVC_STREAM_PTS | UVC_STREAM_SCR)) {
+	case UVC_STREAM_PTS | UVC_STREAM_SCR:
+		header_size = 12;
+		has_pts = true;
+		has_scr = true;
+		break;
+	case UVC_STREAM_PTS:
+		header_size = 6;
+		has_pts = true;
+		break;
+	case UVC_STREAM_SCR:
+		header_size = 8;
+		has_scr = true;
+		break;
+	default:
+		header_size = 2;
+		break;
+	}
+
+	/* Check for invalid headers. */
+	if (len < header_size)
+		return;
+
+	/*
+	 * Extract the timestamps:
+	 *
+	 * - store the frame PTS in the buffer structure
+	 * - if the SCR field is present, retrieve the host SOF counter and
+	 *   kernel timestamps and store them with the SCR STC and SOF fields
+	 *   in the ring buffer
+	 */
+	if (has_pts && buf != NULL)
+		buf->pts = get_unaligned_le32(&data[2]);
+
+	if (!has_scr)
+		return;
+
+	/*
+	 * To limit the amount of data, drop SCRs with an SOF identical to the
+	 * previous one. This filtering is also needed to support UVC 1.5, where
+	 * all the data packets of the same frame contains the same SOF. In that
+	 * case only the first one will match the host_sof.
+	 */
+	dev_sof = get_unaligned_le16(&data[header_size - 2]);
+	if (dev_sof == stream->clock.last_sof)
+		return;
+
+	stream->clock.last_sof = dev_sof;
+
+	host_sof = usb_get_current_frame_number(stream->dev->udev);
+	time = uvc_video_get_time();
+
+	/*
+	 * The UVC specification allows device implementations that can't obtain
+	 * the USB frame number to keep their own frame counters as long as they
+	 * match the size and frequency of the frame number associated with USB
+	 * SOF tokens. The SOF values sent by such devices differ from the USB
+	 * SOF tokens by a fixed offset that needs to be estimated and accounted
+	 * for to make timestamp recovery as accurate as possible.
+	 *
+	 * The offset is estimated the first time a device SOF value is received
+	 * as the difference between the host and device SOF values. As the two
+	 * SOF values can differ slightly due to transmission delays, consider
+	 * that the offset is null if the difference is not higher than 10 ms
+	 * (negative differences can not happen and are thus considered as an
+	 * offset). The video commit control wDelay field should be used to
+	 * compute a dynamic threshold instead of using a fixed 10 ms value, but
+	 * devices don't report reliable wDelay values.
+	 *
+	 * See uvc_video_clock_host_sof() for an explanation regarding why only
+	 * the 8 LSBs of the delta are kept.
+	 */
+	if (stream->clock.sof_offset == (u16)-1) {
+		u16 delta_sof = (host_sof - dev_sof) & 255;
+		if (delta_sof >= 10)
+			stream->clock.sof_offset = delta_sof;
+		else
+			stream->clock.sof_offset = 0;
+	}
+
+	dev_sof = (dev_sof + stream->clock.sof_offset) & 2047;
+
+	spin_lock_irqsave(&stream->clock.lock, flags);
+
+	sample = &stream->clock.samples[stream->clock.head];
+	sample->dev_stc = get_unaligned_le32(&data[header_size - 6]);
+	sample->dev_sof = dev_sof;
+	sample->host_sof = host_sof;
+	sample->host_time = time;
+
+	/* Update the sliding window head and count. */
+	stream->clock.head = (stream->clock.head + 1) % stream->clock.size;
+
+	if (stream->clock.count < stream->clock.size)
+		stream->clock.count++;
+
+	spin_unlock_irqrestore(&stream->clock.lock, flags);
+}
+
+static void uvc_video_clock_reset(struct uvc_streaming *stream)
+{
+	struct uvc_clock *clock = &stream->clock;
+
+	clock->head = 0;
+	clock->count = 0;
+	clock->last_sof = -1;
+	clock->sof_offset = -1;
+}
+
+static int uvc_video_clock_init(struct uvc_streaming *stream)
+{
+	struct uvc_clock *clock = &stream->clock;
+
+	spin_lock_init(&clock->lock);
+	clock->size = 32;
+
+	clock->samples = kmalloc_array(clock->size, sizeof(*clock->samples),
+				       GFP_KERNEL);
+	if (clock->samples == NULL)
+		return -ENOMEM;
+
+	uvc_video_clock_reset(stream);
+
+	return 0;
+}
+
+static void uvc_video_clock_cleanup(struct uvc_streaming *stream)
+{
+	kfree(stream->clock.samples);
+	stream->clock.samples = NULL;
+}
+
+/*
+ * uvc_video_clock_host_sof - Return the host SOF value for a clock sample
+ *
+ * Host SOF counters reported by usb_get_current_frame_number() usually don't
+ * cover the whole 11-bits SOF range (0-2047) but are limited to the HCI frame
+ * schedule window. They can be limited to 8, 9 or 10 bits depending on the host
+ * controller and its configuration.
+ *
+ * We thus need to recover the SOF value corresponding to the host frame number.
+ * As the device and host frame numbers are sampled in a short interval, the
+ * difference between their values should be equal to a small delta plus an
+ * integer multiple of 256 caused by the host frame number limited precision.
+ *
+ * To obtain the recovered host SOF value, compute the small delta by masking
+ * the high bits of the host frame counter and device SOF difference and add it
+ * to the device SOF value.
+ */
+static u16 uvc_video_clock_host_sof(const struct uvc_clock_sample *sample)
+{
+	/* The delta value can be negative. */
+	s8 delta_sof;
+
+	delta_sof = (sample->host_sof - sample->dev_sof) & 255;
+
+	return (sample->dev_sof + delta_sof) & 2047;
+}
+
+/*
+ * uvc_video_clock_update - Update the buffer timestamp
+ *
+ * This function converts the buffer PTS timestamp to the host clock domain by
+ * going through the USB SOF clock domain and stores the result in the V4L2
+ * buffer timestamp field.
+ *
+ * The relationship between the device clock and the host clock isn't known.
+ * However, the device and the host share the common USB SOF clock which can be
+ * used to recover that relationship.
+ *
+ * The relationship between the device clock and the USB SOF clock is considered
+ * to be linear over the clock samples sliding window and is given by
+ *
+ * SOF = m * PTS + p
+ *
+ * Several methods to compute the slope (m) and intercept (p) can be used. As
+ * the clock drift should be small compared to the sliding window size, we
+ * assume that the line that goes through the points at both ends of the window
+ * is a good approximation. Naming those points P1 and P2, we get
+ *
+ * SOF = (SOF2 - SOF1) / (STC2 - STC1) * PTS
+ *     + (SOF1 * STC2 - SOF2 * STC1) / (STC2 - STC1)
+ *
+ * or
+ *
+ * SOF = ((SOF2 - SOF1) * PTS + SOF1 * STC2 - SOF2 * STC1) / (STC2 - STC1)   (1)
+ *
+ * to avoid losing precision in the division. Similarly, the host timestamp is
+ * computed with
+ *
+ * TS = ((TS2 - TS1) * SOF + TS1 * SOF2 - TS2 * SOF1) / (SOF2 - SOF1)	     (2)
+ *
+ * SOF values are coded on 11 bits by USB. We extend their precision with 16
+ * decimal bits, leading to a 11.16 coding.
+ *
+ * TODO: To avoid surprises with device clock values, PTS/STC timestamps should
+ * be normalized using the nominal device clock frequency reported through the
+ * UVC descriptors.
+ *
+ * Both the PTS/STC and SOF counters roll over, after a fixed but device
+ * specific amount of time for PTS/STC and after 2048ms for SOF. As long as the
+ * sliding window size is smaller than the rollover period, differences computed
+ * on unsigned integers will produce the correct result. However, the p term in
+ * the linear relations will be miscomputed.
+ *
+ * To fix the issue, we subtract a constant from the PTS and STC values to bring
+ * PTS to half the 32 bit STC range. The sliding window STC values then fit into
+ * the 32 bit range without any rollover.
+ *
+ * Similarly, we add 2048 to the device SOF values to make sure that the SOF
+ * computed by (1) will never be smaller than 0. This offset is then compensated
+ * by adding 2048 to the SOF values used in (2). However, this doesn't prevent
+ * rollovers between (1) and (2): the SOF value computed by (1) can be slightly
+ * lower than 4096, and the host SOF counters can have rolled over to 2048. This
+ * case is handled by subtracting 2048 from the SOF value if it exceeds the host
+ * SOF value at the end of the sliding window.
+ *
+ * Finally we subtract a constant from the host timestamps to bring the first
+ * timestamp of the sliding window to 1s.
+ */
+void uvc_video_clock_update(struct uvc_streaming *stream,
+			    struct vb2_v4l2_buffer *vbuf,
+			    struct uvc_buffer *buf)
+{
+	struct uvc_clock *clock = &stream->clock;
+	struct uvc_clock_sample *first;
+	struct uvc_clock_sample *last;
+	unsigned long flags;
+	u64 timestamp;
+	u32 delta_stc;
+	u32 y1, y2;
+	u32 x1, x2;
+	u32 mean;
+	u32 sof;
+	u64 y;
+
+	if (!uvc_hw_timestamps_param)
+		return;
+
+	/*
+	 * We will get called from __vb2_queue_cancel() if there are buffers
+	 * done but not dequeued by the user, but the sample array has already
+	 * been released at that time. Just bail out in that case.
+	 */
+	if (!clock->samples)
+		return;
+
+	spin_lock_irqsave(&clock->lock, flags);
+
+	if (clock->count < clock->size)
+		goto done;
+
+	first = &clock->samples[clock->head];
+	last = &clock->samples[(clock->head - 1) % clock->size];
+
+	/* First step, PTS to SOF conversion. */
+	delta_stc = buf->pts - (1UL << 31);
+	x1 = first->dev_stc - delta_stc;
+	x2 = last->dev_stc - delta_stc;
+	if (x1 == x2)
+		goto done;
+
+	y1 = (first->dev_sof + 2048) << 16;
+	y2 = (last->dev_sof + 2048) << 16;
+	if (y2 < y1)
+		y2 += 2048 << 16;
+
+	y = (u64)(y2 - y1) * (1ULL << 31) + (u64)y1 * (u64)x2
+	  - (u64)y2 * (u64)x1;
+	y = div_u64(y, x2 - x1);
+
+	sof = y;
+
+	uvc_dbg(stream->dev, CLOCK,
+		"%s: PTS %u y %llu.%06llu SOF %u.%06llu (x1 %u x2 %u y1 %u y2 %u SOF offset %u)\n",
+		stream->dev->name, buf->pts,
+		y >> 16, div_u64((y & 0xffff) * 1000000, 65536),
+		sof >> 16, div_u64(((u64)sof & 0xffff) * 1000000LLU, 65536),
+		x1, x2, y1, y2, clock->sof_offset);
+
+	/* Second step, SOF to host clock conversion. */
+	x1 = (uvc_video_clock_host_sof(first) + 2048) << 16;
+	x2 = (uvc_video_clock_host_sof(last) + 2048) << 16;
+	if (x2 < x1)
+		x2 += 2048 << 16;
+	if (x1 == x2)
+		goto done;
+
+	y1 = NSEC_PER_SEC;
+	y2 = (u32)ktime_to_ns(ktime_sub(last->host_time, first->host_time)) + y1;
+
+	/*
+	 * Interpolated and host SOF timestamps can wrap around at slightly
+	 * different times. Handle this by adding or removing 2048 to or from
+	 * the computed SOF value to keep it close to the SOF samples mean
+	 * value.
+	 */
+	mean = (x1 + x2) / 2;
+	if (mean - (1024 << 16) > sof)
+		sof += 2048 << 16;
+	else if (sof > mean + (1024 << 16))
+		sof -= 2048 << 16;
+
+	y = (u64)(y2 - y1) * (u64)sof + (u64)y1 * (u64)x2
+	  - (u64)y2 * (u64)x1;
+	y = div_u64(y, x2 - x1);
+
+	timestamp = ktime_to_ns(first->host_time) + y - y1;
+
+	uvc_dbg(stream->dev, CLOCK,
+		"%s: SOF %u.%06llu y %llu ts %llu buf ts %llu (x1 %u/%u/%u x2 %u/%u/%u y1 %u y2 %u)\n",
+		stream->dev->name,
+		sof >> 16, div_u64(((u64)sof & 0xffff) * 1000000LLU, 65536),
+		y, timestamp, vbuf->vb2_buf.timestamp,
+		x1, first->host_sof, first->dev_sof,
+		x2, last->host_sof, last->dev_sof, y1, y2);
+
+	/* Update the V4L2 buffer. */
+	vbuf->vb2_buf.timestamp = timestamp;
+
+done:
+	spin_unlock_irqrestore(&clock->lock, flags);
+}
+
+/* ------------------------------------------------------------------------
+ * Stream statistics
+ */
+
+static void uvc_video_stats_decode(struct uvc_streaming *stream,
+		const u8 *data, int len)
+{
+	unsigned int header_size;
+	bool has_pts = false;
+	bool has_scr = false;
+	u16 scr_sof;
+	u32 scr_stc;
+	u32 pts;
+
+	if (stream->stats.stream.nb_frames == 0 &&
+	    stream->stats.frame.nb_packets == 0)
+		stream->stats.stream.start_ts = ktime_get();
+
+	switch (data[1] & (UVC_STREAM_PTS | UVC_STREAM_SCR)) {
+	case UVC_STREAM_PTS | UVC_STREAM_SCR:
+		header_size = 12;
+		has_pts = true;
+		has_scr = true;
+		break;
+	case UVC_STREAM_PTS:
+		header_size = 6;
+		has_pts = true;
+		break;
+	case UVC_STREAM_SCR:
+		header_size = 8;
+		has_scr = true;
+		break;
+	default:
+		header_size = 2;
+		break;
+	}
+
+	/* Check for invalid headers. */
+	if (len < header_size || data[0] < header_size) {
+		stream->stats.frame.nb_invalid++;
+		return;
+	}
+
+	/* Extract the timestamps. */
+	if (has_pts)
+		pts = get_unaligned_le32(&data[2]);
+
+	if (has_scr) {
+		scr_stc = get_unaligned_le32(&data[header_size - 6]);
+		scr_sof = get_unaligned_le16(&data[header_size - 2]);
+	}
+
+	/* Is PTS constant through the whole frame ? */
+	if (has_pts && stream->stats.frame.nb_pts) {
+		if (stream->stats.frame.pts != pts) {
+			stream->stats.frame.nb_pts_diffs++;
+			stream->stats.frame.last_pts_diff =
+				stream->stats.frame.nb_packets;
+		}
+	}
+
+	if (has_pts) {
+		stream->stats.frame.nb_pts++;
+		stream->stats.frame.pts = pts;
+	}
+
+	/*
+	 * Do all frames have a PTS in their first non-empty packet, or before
+	 * their first empty packet ?
+	 */
+	if (stream->stats.frame.size == 0) {
+		if (len > header_size)
+			stream->stats.frame.has_initial_pts = has_pts;
+		if (len == header_size && has_pts)
+			stream->stats.frame.has_early_pts = true;
+	}
+
+	/* Do the SCR.STC and SCR.SOF fields vary through the frame ? */
+	if (has_scr && stream->stats.frame.nb_scr) {
+		if (stream->stats.frame.scr_stc != scr_stc)
+			stream->stats.frame.nb_scr_diffs++;
+	}
+
+	if (has_scr) {
+		/* Expand the SOF counter to 32 bits and store its value. */
+		if (stream->stats.stream.nb_frames > 0 ||
+		    stream->stats.frame.nb_scr > 0)
+			stream->stats.stream.scr_sof_count +=
+				(scr_sof - stream->stats.stream.scr_sof) % 2048;
+		stream->stats.stream.scr_sof = scr_sof;
+
+		stream->stats.frame.nb_scr++;
+		stream->stats.frame.scr_stc = scr_stc;
+		stream->stats.frame.scr_sof = scr_sof;
+
+		if (scr_sof < stream->stats.stream.min_sof)
+			stream->stats.stream.min_sof = scr_sof;
+		if (scr_sof > stream->stats.stream.max_sof)
+			stream->stats.stream.max_sof = scr_sof;
+	}
+
+	/* Record the first non-empty packet number. */
+	if (stream->stats.frame.size == 0 && len > header_size)
+		stream->stats.frame.first_data = stream->stats.frame.nb_packets;
+
+	/* Update the frame size. */
+	stream->stats.frame.size += len - header_size;
+
+	/* Update the packets counters. */
+	stream->stats.frame.nb_packets++;
+	if (len <= header_size)
+		stream->stats.frame.nb_empty++;
+
+	if (data[1] & UVC_STREAM_ERR)
+		stream->stats.frame.nb_errors++;
+}
+
+static void uvc_video_stats_update(struct uvc_streaming *stream)
+{
+	struct uvc_stats_frame *frame = &stream->stats.frame;
+
+	uvc_dbg(stream->dev, STATS,
+		"frame %u stats: %u/%u/%u packets, %u/%u/%u pts (%searly %sinitial), %u/%u scr, last pts/stc/sof %u/%u/%u\n",
+		stream->sequence, frame->first_data,
+		frame->nb_packets - frame->nb_empty, frame->nb_packets,
+		frame->nb_pts_diffs, frame->last_pts_diff, frame->nb_pts,
+		frame->has_early_pts ? "" : "!",
+		frame->has_initial_pts ? "" : "!",
+		frame->nb_scr_diffs, frame->nb_scr,
+		frame->pts, frame->scr_stc, frame->scr_sof);
+
+	stream->stats.stream.nb_frames++;
+	stream->stats.stream.nb_packets += stream->stats.frame.nb_packets;
+	stream->stats.stream.nb_empty += stream->stats.frame.nb_empty;
+	stream->stats.stream.nb_errors += stream->stats.frame.nb_errors;
+	stream->stats.stream.nb_invalid += stream->stats.frame.nb_invalid;
+
+	if (frame->has_early_pts)
+		stream->stats.stream.nb_pts_early++;
+	if (frame->has_initial_pts)
+		stream->stats.stream.nb_pts_initial++;
+	if (frame->last_pts_diff <= frame->first_data)
+		stream->stats.stream.nb_pts_constant++;
+	if (frame->nb_scr >= frame->nb_packets - frame->nb_empty)
+		stream->stats.stream.nb_scr_count_ok++;
+	if (frame->nb_scr_diffs + 1 == frame->nb_scr)
+		stream->stats.stream.nb_scr_diffs_ok++;
+
+	memset(&stream->stats.frame, 0, sizeof(stream->stats.frame));
+}
+
+size_t uvc_video_stats_dump(struct uvc_streaming *stream, char *buf,
+			    size_t size)
+{
+	unsigned int scr_sof_freq;
+	unsigned int duration;
+	size_t count = 0;
+
+	/*
+	 * Compute the SCR.SOF frequency estimate. At the nominal 1kHz SOF
+	 * frequency this will not overflow before more than 1h.
+	 */
+	duration = ktime_ms_delta(stream->stats.stream.stop_ts,
+				  stream->stats.stream.start_ts);
+	if (duration != 0)
+		scr_sof_freq = stream->stats.stream.scr_sof_count * 1000
+			     / duration;
+	else
+		scr_sof_freq = 0;
+
+	count += scnprintf(buf + count, size - count,
+			   "frames:  %u\npackets: %u\nempty:   %u\n"
+			   "errors:  %u\ninvalid: %u\n",
+			   stream->stats.stream.nb_frames,
+			   stream->stats.stream.nb_packets,
+			   stream->stats.stream.nb_empty,
+			   stream->stats.stream.nb_errors,
+			   stream->stats.stream.nb_invalid);
+	count += scnprintf(buf + count, size - count,
+			   "pts: %u early, %u initial, %u ok\n",
+			   stream->stats.stream.nb_pts_early,
+			   stream->stats.stream.nb_pts_initial,
+			   stream->stats.stream.nb_pts_constant);
+	count += scnprintf(buf + count, size - count,
+			   "scr: %u count ok, %u diff ok\n",
+			   stream->stats.stream.nb_scr_count_ok,
+			   stream->stats.stream.nb_scr_diffs_ok);
+	count += scnprintf(buf + count, size - count,
+			   "sof: %u <= sof <= %u, freq %u.%03u kHz\n",
+			   stream->stats.stream.min_sof,
+			   stream->stats.stream.max_sof,
+			   scr_sof_freq / 1000, scr_sof_freq % 1000);
+
+	return count;
+}
+
+static void uvc_video_stats_start(struct uvc_streaming *stream)
+{
+	memset(&stream->stats, 0, sizeof(stream->stats));
+	stream->stats.stream.min_sof = 2048;
+}
+
+static void uvc_video_stats_stop(struct uvc_streaming *stream)
+{
+	stream->stats.stream.stop_ts = ktime_get();
+}
+
+/* ------------------------------------------------------------------------
+ * Video codecs
+ */
+
+/*
+ * Video payload decoding is handled by uvc_video_decode_start(),
+ * uvc_video_decode_data() and uvc_video_decode_end().
+ *
+ * uvc_video_decode_start is called with URB data at the start of a bulk or
+ * isochronous payload. It processes header data and returns the header size
+ * in bytes if successful. If an error occurs, it returns a negative error
+ * code. The following error codes have special meanings.
+ *
+ * - EAGAIN informs the caller that the current video buffer should be marked
+ *   as done, and that the function should be called again with the same data
+ *   and a new video buffer. This is used when end of frame conditions can be
+ *   reliably detected at the beginning of the next frame only.
+ *
+ * If an error other than -EAGAIN is returned, the caller will drop the current
+ * payload. No call to uvc_video_decode_data and uvc_video_decode_end will be
+ * made until the next payload. -ENODATA can be used to drop the current
+ * payload if no other error code is appropriate.
+ *
+ * uvc_video_decode_data is called for every URB with URB data. It copies the
+ * data to the video buffer.
+ *
+ * uvc_video_decode_end is called with header data at the end of a bulk or
+ * isochronous payload. It performs any additional header data processing and
+ * returns 0 or a negative error code if an error occurred. As header data have
+ * already been processed by uvc_video_decode_start, this functions isn't
+ * required to perform sanity checks a second time.
+ *
+ * For isochronous transfers where a payload is always transferred in a single
+ * URB, the three functions will be called in a row.
+ *
+ * To let the decoder process header data and update its internal state even
+ * when no video buffer is available, uvc_video_decode_start must be prepared
+ * to be called with a NULL buf parameter. uvc_video_decode_data and
+ * uvc_video_decode_end will never be called with a NULL buffer.
+ */
+static int uvc_video_decode_start(struct uvc_streaming *stream,
+		struct uvc_buffer *buf, const u8 *data, int len)
+{
+	u8 fid;
+
+	/*
+	 * Sanity checks:
+	 * - packet must be at least 2 bytes long
+	 * - bHeaderLength value must be at least 2 bytes (see above)
+	 * - bHeaderLength value can't be larger than the packet size.
+	 */
+	if (len < 2 || data[0] < 2 || data[0] > len) {
+		stream->stats.frame.nb_invalid++;
+		return -EINVAL;
+	}
+
+	fid = data[1] & UVC_STREAM_FID;
+
+	/*
+	 * Increase the sequence number regardless of any buffer states, so
+	 * that discontinuous sequence numbers always indicate lost frames.
+	 */
+	if (stream->last_fid != fid) {
+		stream->sequence++;
+		if (stream->sequence)
+			uvc_video_stats_update(stream);
+	}
+
+	uvc_video_clock_decode(stream, buf, data, len);
+	uvc_video_stats_decode(stream, data, len);
+
+	/*
+	 * Store the payload FID bit and return immediately when the buffer is
+	 * NULL.
+	 */
+	if (buf == NULL) {
+		stream->last_fid = fid;
+		return -ENODATA;
+	}
+
+	/* Mark the buffer as bad if the error bit is set. */
+	if (data[1] & UVC_STREAM_ERR) {
+		uvc_dbg(stream->dev, FRAME,
+			"Marking buffer as bad (error bit set)\n");
+		buf->error = 1;
+	}
+
+	/*
+	 * Synchronize to the input stream by waiting for the FID bit to be
+	 * toggled when the buffer state is not UVC_BUF_STATE_ACTIVE.
+	 * stream->last_fid is initialized to -1, so the first isochronous
+	 * frame will always be in sync.
+	 *
+	 * If the device doesn't toggle the FID bit, invert stream->last_fid
+	 * when the EOF bit is set to force synchronisation on the next packet.
+	 */
+	if (buf->state != UVC_BUF_STATE_ACTIVE) {
+		if (fid == stream->last_fid) {
+			uvc_dbg(stream->dev, FRAME,
+				"Dropping payload (out of sync)\n");
+			if ((stream->dev->quirks & UVC_QUIRK_STREAM_NO_FID) &&
+			    (data[1] & UVC_STREAM_EOF))
+				stream->last_fid ^= UVC_STREAM_FID;
+			return -ENODATA;
+		}
+
+		buf->buf.field = V4L2_FIELD_NONE;
+		buf->buf.sequence = stream->sequence;
+		buf->buf.vb2_buf.timestamp = ktime_to_ns(uvc_video_get_time());
+
+		/* TODO: Handle PTS and SCR. */
+		buf->state = UVC_BUF_STATE_ACTIVE;
+	}
+
+	/*
+	 * Mark the buffer as done if we're at the beginning of a new frame.
+	 * End of frame detection is better implemented by checking the EOF
+	 * bit (FID bit toggling is delayed by one frame compared to the EOF
+	 * bit), but some devices don't set the bit at end of frame (and the
+	 * last payload can be lost anyway). We thus must check if the FID has
+	 * been toggled.
+	 *
+	 * stream->last_fid is initialized to -1, so the first isochronous
+	 * frame will never trigger an end of frame detection.
+	 *
+	 * Empty buffers (bytesused == 0) don't trigger end of frame detection
+	 * as it doesn't make sense to return an empty buffer. This also
+	 * avoids detecting end of frame conditions at FID toggling if the
+	 * previous payload had the EOF bit set.
+	 */
+	if (fid != stream->last_fid && buf->bytesused != 0) {
+		uvc_dbg(stream->dev, FRAME,
+			"Frame complete (FID bit toggled)\n");
+		buf->state = UVC_BUF_STATE_READY;
+		return -EAGAIN;
+	}
+
+	stream->last_fid = fid;
+
+	return data[0];
+}
+
+static inline enum dma_data_direction uvc_stream_dir(
+				struct uvc_streaming *stream)
+{
+	if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE)
+		return DMA_FROM_DEVICE;
+	else
+		return DMA_TO_DEVICE;
+}
+
+static inline struct device *uvc_stream_to_dmadev(struct uvc_streaming *stream)
+{
+	return bus_to_hcd(stream->dev->udev->bus)->self.sysdev;
+}
+
+static int uvc_submit_urb(struct uvc_urb *uvc_urb, gfp_t mem_flags)
+{
+	/* Sync DMA. */
+	dma_sync_sgtable_for_device(uvc_stream_to_dmadev(uvc_urb->stream),
+				    uvc_urb->sgt,
+				    uvc_stream_dir(uvc_urb->stream));
+	return usb_submit_urb(uvc_urb->urb, mem_flags);
+}
+
+/*
+ * uvc_video_decode_data_work: Asynchronous memcpy processing
+ *
+ * Copy URB data to video buffers in process context, releasing buffer
+ * references and requeuing the URB when done.
+ */
+static void uvc_video_copy_data_work(struct work_struct *work)
+{
+	struct uvc_urb *uvc_urb = container_of(work, struct uvc_urb, work);
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < uvc_urb->async_operations; i++) {
+		struct uvc_copy_op *op = &uvc_urb->copy_operations[i];
+
+		memcpy(op->dst, op->src, op->len);
+
+		/* Release reference taken on this buffer. */
+		uvc_queue_buffer_release(op->buf);
+	}
+
+	ret = uvc_submit_urb(uvc_urb, GFP_KERNEL);
+	if (ret < 0)
+		dev_err(&uvc_urb->stream->intf->dev,
+			"Failed to resubmit video URB (%d).\n", ret);
+}
+
+static void uvc_video_decode_data(struct uvc_urb *uvc_urb,
+		struct uvc_buffer *buf, const u8 *data, int len)
+{
+	unsigned int active_op = uvc_urb->async_operations;
+	struct uvc_copy_op *op = &uvc_urb->copy_operations[active_op];
+	unsigned int maxlen;
+
+	if (len <= 0)
+		return;
+
+	maxlen = buf->length - buf->bytesused;
+
+	/* Take a buffer reference for async work. */
+	kref_get(&buf->ref);
+
+	op->buf = buf;
+	op->src = data;
+	op->dst = buf->mem + buf->bytesused;
+	op->len = min_t(unsigned int, len, maxlen);
+
+	buf->bytesused += op->len;
+
+	/* Complete the current frame if the buffer size was exceeded. */
+	if (len > maxlen) {
+		uvc_dbg(uvc_urb->stream->dev, FRAME,
+			"Frame complete (overflow)\n");
+		buf->error = 1;
+		buf->state = UVC_BUF_STATE_READY;
+	}
+
+	uvc_urb->async_operations++;
+}
+
+static void uvc_video_decode_end(struct uvc_streaming *stream,
+		struct uvc_buffer *buf, const u8 *data, int len)
+{
+	/* Mark the buffer as done if the EOF marker is set. */
+	if (data[1] & UVC_STREAM_EOF && buf->bytesused != 0) {
+		uvc_dbg(stream->dev, FRAME, "Frame complete (EOF found)\n");
+		if (data[0] == len)
+			uvc_dbg(stream->dev, FRAME, "EOF in empty payload\n");
+		buf->state = UVC_BUF_STATE_READY;
+		if (stream->dev->quirks & UVC_QUIRK_STREAM_NO_FID)
+			stream->last_fid ^= UVC_STREAM_FID;
+	}
+}
+
+/*
+ * Video payload encoding is handled by uvc_video_encode_header() and
+ * uvc_video_encode_data(). Only bulk transfers are currently supported.
+ *
+ * uvc_video_encode_header is called at the start of a payload. It adds header
+ * data to the transfer buffer and returns the header size. As the only known
+ * UVC output device transfers a whole frame in a single payload, the EOF bit
+ * is always set in the header.
+ *
+ * uvc_video_encode_data is called for every URB and copies the data from the
+ * video buffer to the transfer buffer.
+ */
+static int uvc_video_encode_header(struct uvc_streaming *stream,
+		struct uvc_buffer *buf, u8 *data, int len)
+{
+	data[0] = 2;	/* Header length */
+	data[1] = UVC_STREAM_EOH | UVC_STREAM_EOF
+		| (stream->last_fid & UVC_STREAM_FID);
+	return 2;
+}
+
+static int uvc_video_encode_data(struct uvc_streaming *stream,
+		struct uvc_buffer *buf, u8 *data, int len)
+{
+	struct uvc_video_queue *queue = &stream->queue;
+	unsigned int nbytes;
+	void *mem;
+
+	/* Copy video data to the URB buffer. */
+	mem = buf->mem + queue->buf_used;
+	nbytes = min((unsigned int)len, buf->bytesused - queue->buf_used);
+	nbytes = min(stream->bulk.max_payload_size - stream->bulk.payload_size,
+			nbytes);
+	memcpy(data, mem, nbytes);
+
+	queue->buf_used += nbytes;
+
+	return nbytes;
+}
+
+/* ------------------------------------------------------------------------
+ * Metadata
+ */
+
+/*
+ * Additionally to the payload headers we also want to provide the user with USB
+ * Frame Numbers and system time values. The resulting buffer is thus composed
+ * of blocks, containing a 64-bit timestamp in  nanoseconds, a 16-bit USB Frame
+ * Number, and a copy of the payload header.
+ *
+ * Ideally we want to capture all payload headers for each frame. However, their
+ * number is unknown and unbound. We thus drop headers that contain no vendor
+ * data and that either contain no SCR value or an SCR value identical to the
+ * previous header.
+ */
+static void uvc_video_decode_meta(struct uvc_streaming *stream,
+				  struct uvc_buffer *meta_buf,
+				  const u8 *mem, unsigned int length)
+{
+	struct uvc_meta_buf *meta;
+	size_t len_std = 2;
+	bool has_pts, has_scr;
+	unsigned long flags;
+	unsigned int sof;
+	ktime_t time;
+	const u8 *scr;
+
+	if (!meta_buf || length == 2)
+		return;
+
+	if (meta_buf->length - meta_buf->bytesused <
+	    length + sizeof(meta->ns) + sizeof(meta->sof)) {
+		meta_buf->error = 1;
+		return;
+	}
+
+	has_pts = mem[1] & UVC_STREAM_PTS;
+	has_scr = mem[1] & UVC_STREAM_SCR;
+
+	if (has_pts) {
+		len_std += 4;
+		scr = mem + 6;
+	} else {
+		scr = mem + 2;
+	}
+
+	if (has_scr)
+		len_std += 6;
+
+	if (stream->meta.format == V4L2_META_FMT_UVC)
+		length = len_std;
+
+	if (length == len_std && (!has_scr ||
+				  !memcmp(scr, stream->clock.last_scr, 6)))
+		return;
+
+	meta = (struct uvc_meta_buf *)((u8 *)meta_buf->mem + meta_buf->bytesused);
+	local_irq_save(flags);
+	time = uvc_video_get_time();
+	sof = usb_get_current_frame_number(stream->dev->udev);
+	local_irq_restore(flags);
+	put_unaligned(ktime_to_ns(time), &meta->ns);
+	put_unaligned(sof, &meta->sof);
+
+	if (has_scr)
+		memcpy(stream->clock.last_scr, scr, 6);
+
+	meta->length = mem[0];
+	meta->flags  = mem[1];
+	memcpy(meta->buf, &mem[2], length - 2);
+	meta_buf->bytesused += length + sizeof(meta->ns) + sizeof(meta->sof);
+
+	uvc_dbg(stream->dev, FRAME,
+		"%s(): t-sys %lluns, SOF %u, len %u, flags 0x%x, PTS %u, STC %u frame SOF %u\n",
+		__func__, ktime_to_ns(time), meta->sof, meta->length,
+		meta->flags,
+		has_pts ? *(u32 *)meta->buf : 0,
+		has_scr ? *(u32 *)scr : 0,
+		has_scr ? *(u32 *)(scr + 4) & 0x7ff : 0);
+}
+
+/* ------------------------------------------------------------------------
+ * URB handling
+ */
+
+/*
+ * Set error flag for incomplete buffer.
+ */
+static void uvc_video_validate_buffer(const struct uvc_streaming *stream,
+				      struct uvc_buffer *buf)
+{
+	if (stream->ctrl.dwMaxVideoFrameSize != buf->bytesused &&
+	    !(stream->cur_format->flags & UVC_FMT_FLAG_COMPRESSED))
+		buf->error = 1;
+}
+
+/*
+ * Completion handler for video URBs.
+ */
+
+static void uvc_video_next_buffers(struct uvc_streaming *stream,
+		struct uvc_buffer **video_buf, struct uvc_buffer **meta_buf)
+{
+	uvc_video_validate_buffer(stream, *video_buf);
+
+	if (*meta_buf) {
+		struct vb2_v4l2_buffer *vb2_meta = &(*meta_buf)->buf;
+		const struct vb2_v4l2_buffer *vb2_video = &(*video_buf)->buf;
+
+		vb2_meta->sequence = vb2_video->sequence;
+		vb2_meta->field = vb2_video->field;
+		vb2_meta->vb2_buf.timestamp = vb2_video->vb2_buf.timestamp;
+
+		(*meta_buf)->state = UVC_BUF_STATE_READY;
+		if (!(*meta_buf)->error)
+			(*meta_buf)->error = (*video_buf)->error;
+		*meta_buf = uvc_queue_next_buffer(&stream->meta.queue,
+						  *meta_buf);
+	}
+	*video_buf = uvc_queue_next_buffer(&stream->queue, *video_buf);
+}
+
+static void uvc_video_decode_isoc(struct uvc_urb *uvc_urb,
+			struct uvc_buffer *buf, struct uvc_buffer *meta_buf)
+{
+	struct urb *urb = uvc_urb->urb;
+	struct uvc_streaming *stream = uvc_urb->stream;
+	u8 *mem;
+	int ret, i;
+
+	for (i = 0; i < urb->number_of_packets; ++i) {
+		if (urb->iso_frame_desc[i].status < 0) {
+			uvc_dbg(stream->dev, FRAME,
+				"USB isochronous frame lost (%d)\n",
+				urb->iso_frame_desc[i].status);
+			/* Mark the buffer as faulty. */
+			if (buf != NULL)
+				buf->error = 1;
+			continue;
+		}
+
+		/* Decode the payload header. */
+		mem = urb->transfer_buffer + urb->iso_frame_desc[i].offset;
+		do {
+			ret = uvc_video_decode_start(stream, buf, mem,
+				urb->iso_frame_desc[i].actual_length);
+			if (ret == -EAGAIN)
+				uvc_video_next_buffers(stream, &buf, &meta_buf);
+		} while (ret == -EAGAIN);
+
+		if (ret < 0)
+			continue;
+
+		uvc_video_decode_meta(stream, meta_buf, mem, ret);
+
+		/* Decode the payload data. */
+		uvc_video_decode_data(uvc_urb, buf, mem + ret,
+			urb->iso_frame_desc[i].actual_length - ret);
+
+		/* Process the header again. */
+		uvc_video_decode_end(stream, buf, mem,
+			urb->iso_frame_desc[i].actual_length);
+
+		if (buf->state == UVC_BUF_STATE_READY)
+			uvc_video_next_buffers(stream, &buf, &meta_buf);
+	}
+}
+
+static void uvc_video_decode_bulk(struct uvc_urb *uvc_urb,
+			struct uvc_buffer *buf, struct uvc_buffer *meta_buf)
+{
+	struct urb *urb = uvc_urb->urb;
+	struct uvc_streaming *stream = uvc_urb->stream;
+	u8 *mem;
+	int len, ret;
+
+	/*
+	 * Ignore ZLPs if they're not part of a frame, otherwise process them
+	 * to trigger the end of payload detection.
+	 */
+	if (urb->actual_length == 0 && stream->bulk.header_size == 0)
+		return;
+
+	mem = urb->transfer_buffer;
+	len = urb->actual_length;
+	stream->bulk.payload_size += len;
+
+	/*
+	 * If the URB is the first of its payload, decode and save the
+	 * header.
+	 */
+	if (stream->bulk.header_size == 0 && !stream->bulk.skip_payload) {
+		do {
+			ret = uvc_video_decode_start(stream, buf, mem, len);
+			if (ret == -EAGAIN)
+				uvc_video_next_buffers(stream, &buf, &meta_buf);
+		} while (ret == -EAGAIN);
+
+		/* If an error occurred skip the rest of the payload. */
+		if (ret < 0 || buf == NULL) {
+			stream->bulk.skip_payload = 1;
+		} else {
+			memcpy(stream->bulk.header, mem, ret);
+			stream->bulk.header_size = ret;
+
+			uvc_video_decode_meta(stream, meta_buf, mem, ret);
+
+			mem += ret;
+			len -= ret;
+		}
+	}
+
+	/*
+	 * The buffer queue might have been cancelled while a bulk transfer
+	 * was in progress, so we can reach here with buf equal to NULL. Make
+	 * sure buf is never dereferenced if NULL.
+	 */
+
+	/* Prepare video data for processing. */
+	if (!stream->bulk.skip_payload && buf != NULL)
+		uvc_video_decode_data(uvc_urb, buf, mem, len);
+
+	/*
+	 * Detect the payload end by a URB smaller than the maximum size (or
+	 * a payload size equal to the maximum) and process the header again.
+	 */
+	if (urb->actual_length < urb->transfer_buffer_length ||
+	    stream->bulk.payload_size >= stream->bulk.max_payload_size) {
+		if (!stream->bulk.skip_payload && buf != NULL) {
+			uvc_video_decode_end(stream, buf, stream->bulk.header,
+				stream->bulk.payload_size);
+			if (buf->state == UVC_BUF_STATE_READY)
+				uvc_video_next_buffers(stream, &buf, &meta_buf);
+		}
+
+		stream->bulk.header_size = 0;
+		stream->bulk.skip_payload = 0;
+		stream->bulk.payload_size = 0;
+	}
+}
+
+static void uvc_video_encode_bulk(struct uvc_urb *uvc_urb,
+	struct uvc_buffer *buf, struct uvc_buffer *meta_buf)
+{
+	struct urb *urb = uvc_urb->urb;
+	struct uvc_streaming *stream = uvc_urb->stream;
+
+	u8 *mem = urb->transfer_buffer;
+	int len = stream->urb_size, ret;
+
+	if (buf == NULL) {
+		urb->transfer_buffer_length = 0;
+		return;
+	}
+
+	/* If the URB is the first of its payload, add the header. */
+	if (stream->bulk.header_size == 0) {
+		ret = uvc_video_encode_header(stream, buf, mem, len);
+		stream->bulk.header_size = ret;
+		stream->bulk.payload_size += ret;
+		mem += ret;
+		len -= ret;
+	}
+
+	/* Process video data. */
+	ret = uvc_video_encode_data(stream, buf, mem, len);
+
+	stream->bulk.payload_size += ret;
+	len -= ret;
+
+	if (buf->bytesused == stream->queue.buf_used ||
+	    stream->bulk.payload_size == stream->bulk.max_payload_size) {
+		if (buf->bytesused == stream->queue.buf_used) {
+			stream->queue.buf_used = 0;
+			buf->state = UVC_BUF_STATE_READY;
+			buf->buf.sequence = ++stream->sequence;
+			uvc_queue_next_buffer(&stream->queue, buf);
+			stream->last_fid ^= UVC_STREAM_FID;
+		}
+
+		stream->bulk.header_size = 0;
+		stream->bulk.payload_size = 0;
+	}
+
+	urb->transfer_buffer_length = stream->urb_size - len;
+}
+
+static void uvc_video_complete(struct urb *urb)
+{
+	struct uvc_urb *uvc_urb = urb->context;
+	struct uvc_streaming *stream = uvc_urb->stream;
+	struct uvc_video_queue *queue = &stream->queue;
+	struct uvc_video_queue *qmeta = &stream->meta.queue;
+	struct vb2_queue *vb2_qmeta = stream->meta.vdev.queue;
+	struct uvc_buffer *buf = NULL;
+	struct uvc_buffer *buf_meta = NULL;
+	unsigned long flags;
+	int ret;
+
+	switch (urb->status) {
+	case 0:
+		break;
+
+	default:
+		dev_warn(&stream->intf->dev,
+			 "Non-zero status (%d) in video completion handler.\n",
+			 urb->status);
+		fallthrough;
+	case -ENOENT:		/* usb_poison_urb() called. */
+		if (stream->frozen)
+			return;
+		fallthrough;
+	case -ECONNRESET:	/* usb_unlink_urb() called. */
+	case -ESHUTDOWN:	/* The endpoint is being disabled. */
+		uvc_queue_cancel(queue, urb->status == -ESHUTDOWN);
+		if (vb2_qmeta)
+			uvc_queue_cancel(qmeta, urb->status == -ESHUTDOWN);
+		return;
+	}
+
+	buf = uvc_queue_get_current_buffer(queue);
+
+	if (vb2_qmeta) {
+		spin_lock_irqsave(&qmeta->irqlock, flags);
+		if (!list_empty(&qmeta->irqqueue))
+			buf_meta = list_first_entry(&qmeta->irqqueue,
+						    struct uvc_buffer, queue);
+		spin_unlock_irqrestore(&qmeta->irqlock, flags);
+	}
+
+	/* Re-initialise the URB async work. */
+	uvc_urb->async_operations = 0;
+
+	/* Sync DMA and invalidate vmap range. */
+	dma_sync_sgtable_for_cpu(uvc_stream_to_dmadev(uvc_urb->stream),
+				 uvc_urb->sgt, uvc_stream_dir(stream));
+	invalidate_kernel_vmap_range(uvc_urb->buffer,
+				     uvc_urb->stream->urb_size);
+
+	/*
+	 * Process the URB headers, and optionally queue expensive memcpy tasks
+	 * to be deferred to a work queue.
+	 */
+	stream->decode(uvc_urb, buf, buf_meta);
+
+	/* If no async work is needed, resubmit the URB immediately. */
+	if (!uvc_urb->async_operations) {
+		ret = uvc_submit_urb(uvc_urb, GFP_ATOMIC);
+		if (ret < 0)
+			dev_err(&stream->intf->dev,
+				"Failed to resubmit video URB (%d).\n", ret);
+		return;
+	}
+
+	queue_work(stream->async_wq, &uvc_urb->work);
+}
+
+/*
+ * Free transfer buffers.
+ */
+static void uvc_free_urb_buffers(struct uvc_streaming *stream)
+{
+	struct device *dma_dev = uvc_stream_to_dmadev(stream);
+	struct uvc_urb *uvc_urb;
+
+	for_each_uvc_urb(uvc_urb, stream) {
+		if (!uvc_urb->buffer)
+			continue;
+
+		dma_vunmap_noncontiguous(dma_dev, uvc_urb->buffer);
+		dma_free_noncontiguous(dma_dev, stream->urb_size, uvc_urb->sgt,
+				       uvc_stream_dir(stream));
+
+		uvc_urb->buffer = NULL;
+		uvc_urb->sgt = NULL;
+	}
+
+	stream->urb_size = 0;
+}
+
+static bool uvc_alloc_urb_buffer(struct uvc_streaming *stream,
+				 struct uvc_urb *uvc_urb, gfp_t gfp_flags)
+{
+	struct device *dma_dev = uvc_stream_to_dmadev(stream);
+
+	uvc_urb->sgt = dma_alloc_noncontiguous(dma_dev, stream->urb_size,
+					       uvc_stream_dir(stream),
+					       gfp_flags, 0);
+	if (!uvc_urb->sgt)
+		return false;
+	uvc_urb->dma = uvc_urb->sgt->sgl->dma_address;
+
+	uvc_urb->buffer = dma_vmap_noncontiguous(dma_dev, stream->urb_size,
+						 uvc_urb->sgt);
+	if (!uvc_urb->buffer) {
+		dma_free_noncontiguous(dma_dev, stream->urb_size,
+				       uvc_urb->sgt,
+				       uvc_stream_dir(stream));
+		uvc_urb->sgt = NULL;
+		return false;
+	}
+
+	return true;
+}
+
+/*
+ * Allocate transfer buffers. This function can be called with buffers
+ * already allocated when resuming from suspend, in which case it will
+ * return without touching the buffers.
+ *
+ * Limit the buffer size to UVC_MAX_PACKETS bulk/isochronous packets. If the
+ * system is too low on memory try successively smaller numbers of packets
+ * until allocation succeeds.
+ *
+ * Return the number of allocated packets on success or 0 when out of memory.
+ */
+static int uvc_alloc_urb_buffers(struct uvc_streaming *stream,
+	unsigned int size, unsigned int psize, gfp_t gfp_flags)
+{
+	unsigned int npackets;
+	unsigned int i;
+
+	/* Buffers are already allocated, bail out. */
+	if (stream->urb_size)
+		return stream->urb_size / psize;
+
+	/*
+	 * Compute the number of packets. Bulk endpoints might transfer UVC
+	 * payloads across multiple URBs.
+	 */
+	npackets = DIV_ROUND_UP(size, psize);
+	if (npackets > UVC_MAX_PACKETS)
+		npackets = UVC_MAX_PACKETS;
+
+	/* Retry allocations until one succeed. */
+	for (; npackets > 1; npackets /= 2) {
+		stream->urb_size = psize * npackets;
+
+		for (i = 0; i < UVC_URBS; ++i) {
+			struct uvc_urb *uvc_urb = &stream->uvc_urb[i];
+
+			if (!uvc_alloc_urb_buffer(stream, uvc_urb, gfp_flags)) {
+				uvc_free_urb_buffers(stream);
+				break;
+			}
+
+			uvc_urb->stream = stream;
+		}
+
+		if (i == UVC_URBS) {
+			uvc_dbg(stream->dev, VIDEO,
+				"Allocated %u URB buffers of %ux%u bytes each\n",
+				UVC_URBS, npackets, psize);
+			return npackets;
+		}
+	}
+
+	uvc_dbg(stream->dev, VIDEO,
+		"Failed to allocate URB buffers (%u bytes per packet)\n",
+		psize);
+	return 0;
+}
+
+/*
+ * Uninitialize isochronous/bulk URBs and free transfer buffers.
+ */
+static void uvc_video_stop_transfer(struct uvc_streaming *stream,
+				    int free_buffers)
+{
+	struct uvc_urb *uvc_urb;
+
+	uvc_video_stats_stop(stream);
+
+	/*
+	 * We must poison the URBs rather than kill them to ensure that even
+	 * after the completion handler returns, any asynchronous workqueues
+	 * will be prevented from resubmitting the URBs.
+	 */
+	for_each_uvc_urb(uvc_urb, stream)
+		usb_poison_urb(uvc_urb->urb);
+
+	flush_workqueue(stream->async_wq);
+
+	for_each_uvc_urb(uvc_urb, stream) {
+		usb_free_urb(uvc_urb->urb);
+		uvc_urb->urb = NULL;
+	}
+
+	if (free_buffers)
+		uvc_free_urb_buffers(stream);
+}
+
+/*
+ * Compute the maximum number of bytes per interval for an endpoint.
+ */
+u16 uvc_endpoint_max_bpi(struct usb_device *dev, struct usb_host_endpoint *ep)
+{
+	u16 psize;
+
+	switch (dev->speed) {
+	case USB_SPEED_SUPER:
+	case USB_SPEED_SUPER_PLUS:
+		return le16_to_cpu(ep->ss_ep_comp.wBytesPerInterval);
+	default:
+		psize = usb_endpoint_maxp(&ep->desc);
+		psize *= usb_endpoint_maxp_mult(&ep->desc);
+		return psize;
+	}
+}
+
+/*
+ * Initialize isochronous URBs and allocate transfer buffers. The packet size
+ * is given by the endpoint.
+ */
+static int uvc_init_video_isoc(struct uvc_streaming *stream,
+	struct usb_host_endpoint *ep, gfp_t gfp_flags)
+{
+	struct urb *urb;
+	struct uvc_urb *uvc_urb;
+	unsigned int npackets, i;
+	u16 psize;
+	u32 size;
+
+	psize = uvc_endpoint_max_bpi(stream->dev->udev, ep);
+	size = stream->ctrl.dwMaxVideoFrameSize;
+
+	npackets = uvc_alloc_urb_buffers(stream, size, psize, gfp_flags);
+	if (npackets == 0)
+		return -ENOMEM;
+
+	size = npackets * psize;
+
+	for_each_uvc_urb(uvc_urb, stream) {
+		urb = usb_alloc_urb(npackets, gfp_flags);
+		if (urb == NULL) {
+			uvc_video_stop_transfer(stream, 1);
+			return -ENOMEM;
+		}
+
+		urb->dev = stream->dev->udev;
+		urb->context = uvc_urb;
+		urb->pipe = usb_rcvisocpipe(stream->dev->udev,
+				ep->desc.bEndpointAddress);
+		urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
+		urb->transfer_dma = uvc_urb->dma;
+		urb->interval = ep->desc.bInterval;
+		urb->transfer_buffer = uvc_urb->buffer;
+		urb->complete = uvc_video_complete;
+		urb->number_of_packets = npackets;
+		urb->transfer_buffer_length = size;
+
+		for (i = 0; i < npackets; ++i) {
+			urb->iso_frame_desc[i].offset = i * psize;
+			urb->iso_frame_desc[i].length = psize;
+		}
+
+		uvc_urb->urb = urb;
+	}
+
+	return 0;
+}
+
+/*
+ * Initialize bulk URBs and allocate transfer buffers. The packet size is
+ * given by the endpoint.
+ */
+static int uvc_init_video_bulk(struct uvc_streaming *stream,
+	struct usb_host_endpoint *ep, gfp_t gfp_flags)
+{
+	struct urb *urb;
+	struct uvc_urb *uvc_urb;
+	unsigned int npackets, pipe;
+	u16 psize;
+	u32 size;
+
+	psize = usb_endpoint_maxp(&ep->desc);
+	size = stream->ctrl.dwMaxPayloadTransferSize;
+	stream->bulk.max_payload_size = size;
+
+	npackets = uvc_alloc_urb_buffers(stream, size, psize, gfp_flags);
+	if (npackets == 0)
+		return -ENOMEM;
+
+	size = npackets * psize;
+
+	if (usb_endpoint_dir_in(&ep->desc))
+		pipe = usb_rcvbulkpipe(stream->dev->udev,
+				       ep->desc.bEndpointAddress);
+	else
+		pipe = usb_sndbulkpipe(stream->dev->udev,
+				       ep->desc.bEndpointAddress);
+
+	if (stream->type == V4L2_BUF_TYPE_VIDEO_OUTPUT)
+		size = 0;
+
+	for_each_uvc_urb(uvc_urb, stream) {
+		urb = usb_alloc_urb(0, gfp_flags);
+		if (urb == NULL) {
+			uvc_video_stop_transfer(stream, 1);
+			return -ENOMEM;
+		}
+
+		usb_fill_bulk_urb(urb, stream->dev->udev, pipe,	uvc_urb->buffer,
+				  size, uvc_video_complete, uvc_urb);
+		urb->transfer_flags = URB_NO_TRANSFER_DMA_MAP;
+		urb->transfer_dma = uvc_urb->dma;
+
+		uvc_urb->urb = urb;
+	}
+
+	return 0;
+}
+
+/*
+ * Initialize isochronous/bulk URBs and allocate transfer buffers.
+ */
+static int uvc_video_start_transfer(struct uvc_streaming *stream,
+				    gfp_t gfp_flags)
+{
+	struct usb_interface *intf = stream->intf;
+	struct usb_host_endpoint *ep;
+	struct uvc_urb *uvc_urb;
+	unsigned int i;
+	int ret;
+
+	stream->sequence = -1;
+	stream->last_fid = -1;
+	stream->bulk.header_size = 0;
+	stream->bulk.skip_payload = 0;
+	stream->bulk.payload_size = 0;
+
+	uvc_video_stats_start(stream);
+
+	if (intf->num_altsetting > 1) {
+		struct usb_host_endpoint *best_ep = NULL;
+		unsigned int best_psize = UINT_MAX;
+		unsigned int bandwidth;
+		unsigned int altsetting;
+		int intfnum = stream->intfnum;
+
+		/* Isochronous endpoint, select the alternate setting. */
+		bandwidth = stream->ctrl.dwMaxPayloadTransferSize;
+
+		if (bandwidth == 0) {
+			uvc_dbg(stream->dev, VIDEO,
+				"Device requested null bandwidth, defaulting to lowest\n");
+			bandwidth = 1;
+		} else {
+			uvc_dbg(stream->dev, VIDEO,
+				"Device requested %u B/frame bandwidth\n",
+				bandwidth);
+		}
+
+		for (i = 0; i < intf->num_altsetting; ++i) {
+			struct usb_host_interface *alts;
+			unsigned int psize;
+
+			alts = &intf->altsetting[i];
+			ep = uvc_find_endpoint(alts,
+				stream->header.bEndpointAddress);
+			if (ep == NULL)
+				continue;
+
+			/* Check if the bandwidth is high enough. */
+			psize = uvc_endpoint_max_bpi(stream->dev->udev, ep);
+			if (psize >= bandwidth && psize <= best_psize) {
+				altsetting = alts->desc.bAlternateSetting;
+				best_psize = psize;
+				best_ep = ep;
+			}
+		}
+
+		if (best_ep == NULL) {
+			uvc_dbg(stream->dev, VIDEO,
+				"No fast enough alt setting for requested bandwidth\n");
+			return -EIO;
+		}
+
+		uvc_dbg(stream->dev, VIDEO,
+			"Selecting alternate setting %u (%u B/frame bandwidth)\n",
+			altsetting, best_psize);
+
+		/*
+		 * Some devices, namely the Logitech C910 and B910, are unable
+		 * to recover from a USB autosuspend, unless the alternate
+		 * setting of the streaming interface is toggled.
+		 */
+		if (stream->dev->quirks & UVC_QUIRK_WAKE_AUTOSUSPEND) {
+			usb_set_interface(stream->dev->udev, intfnum,
+					  altsetting);
+			usb_set_interface(stream->dev->udev, intfnum, 0);
+		}
+
+		ret = usb_set_interface(stream->dev->udev, intfnum, altsetting);
+		if (ret < 0)
+			return ret;
+
+		ret = uvc_init_video_isoc(stream, best_ep, gfp_flags);
+	} else {
+		/* Bulk endpoint, proceed to URB initialization. */
+		ep = uvc_find_endpoint(&intf->altsetting[0],
+				stream->header.bEndpointAddress);
+		if (ep == NULL)
+			return -EIO;
+
+		/* Reject broken descriptors. */
+		if (usb_endpoint_maxp(&ep->desc) == 0)
+			return -EIO;
+
+		ret = uvc_init_video_bulk(stream, ep, gfp_flags);
+	}
+
+	if (ret < 0)
+		return ret;
+
+	/* Submit the URBs. */
+	for_each_uvc_urb(uvc_urb, stream) {
+		ret = uvc_submit_urb(uvc_urb, gfp_flags);
+		if (ret < 0) {
+			dev_err(&stream->intf->dev,
+				"Failed to submit URB %u (%d).\n",
+				uvc_urb_index(uvc_urb), ret);
+			uvc_video_stop_transfer(stream, 1);
+			return ret;
+		}
+	}
+
+	/*
+	 * The Logitech C920 temporarily forgets that it should not be adjusting
+	 * Exposure Absolute during init so restore controls to stored values.
+	 */
+	if (stream->dev->quirks & UVC_QUIRK_RESTORE_CTRLS_ON_INIT)
+		uvc_ctrl_restore_values(stream->dev);
+
+	return 0;
+}
+
+/* --------------------------------------------------------------------------
+ * Suspend/resume
+ */
+
+/*
+ * Stop streaming without disabling the video queue.
+ *
+ * To let userspace applications resume without trouble, we must not touch the
+ * video buffers in any way. We mark the device as frozen to make sure the URB
+ * completion handler won't try to cancel the queue when we kill the URBs.
+ */
+int uvc_video_suspend(struct uvc_streaming *stream)
+{
+	if (!uvc_queue_streaming(&stream->queue))
+		return 0;
+
+	stream->frozen = 1;
+	uvc_video_stop_transfer(stream, 0);
+	usb_set_interface(stream->dev->udev, stream->intfnum, 0);
+	return 0;
+}
+
+/*
+ * Reconfigure the video interface and restart streaming if it was enabled
+ * before suspend.
+ *
+ * If an error occurs, disable the video queue. This will wake all pending
+ * buffers, making sure userspace applications are notified of the problem
+ * instead of waiting forever.
+ */
+int uvc_video_resume(struct uvc_streaming *stream, int reset)
+{
+	int ret;
+
+	/*
+	 * If the bus has been reset on resume, set the alternate setting to 0.
+	 * This should be the default value, but some devices crash or otherwise
+	 * misbehave if they don't receive a SET_INTERFACE request before any
+	 * other video control request.
+	 */
+	if (reset)
+		usb_set_interface(stream->dev->udev, stream->intfnum, 0);
+
+	stream->frozen = 0;
+
+	uvc_video_clock_reset(stream);
+
+	if (!uvc_queue_streaming(&stream->queue))
+		return 0;
+
+	ret = uvc_commit_video(stream, &stream->ctrl);
+	if (ret < 0)
+		return ret;
+
+	return uvc_video_start_transfer(stream, GFP_NOIO);
+}
+
+/* ------------------------------------------------------------------------
+ * Video device
+ */
+
+/*
+ * Initialize the UVC video device by switching to alternate setting 0 and
+ * retrieve the default format.
+ *
+ * Some cameras (namely the Fuji Finepix) set the format and frame
+ * indexes to zero. The UVC standard doesn't clearly make this a spec
+ * violation, so try to silently fix the values if possible.
+ *
+ * This function is called before registering the device with V4L.
+ */
+int uvc_video_init(struct uvc_streaming *stream)
+{
+	struct uvc_streaming_control *probe = &stream->ctrl;
+	const struct uvc_format *format = NULL;
+	const struct uvc_frame *frame = NULL;
+	struct uvc_urb *uvc_urb;
+	unsigned int i;
+	int ret;
+
+	if (stream->nformats == 0) {
+		dev_info(&stream->intf->dev,
+			 "No supported video formats found.\n");
+		return -EINVAL;
+	}
+
+	atomic_set(&stream->active, 0);
+
+	/*
+	 * Alternate setting 0 should be the default, yet the XBox Live Vision
+	 * Cam (and possibly other devices) crash or otherwise misbehave if
+	 * they don't receive a SET_INTERFACE request before any other video
+	 * control request.
+	 */
+	usb_set_interface(stream->dev->udev, stream->intfnum, 0);
+
+	/*
+	 * Set the streaming probe control with default streaming parameters
+	 * retrieved from the device. Webcams that don't support GET_DEF
+	 * requests on the probe control will just keep their current streaming
+	 * parameters.
+	 */
+	if (uvc_get_video_ctrl(stream, probe, 1, UVC_GET_DEF) == 0)
+		uvc_set_video_ctrl(stream, probe, 1);
+
+	/*
+	 * Initialize the streaming parameters with the probe control current
+	 * value. This makes sure SET_CUR requests on the streaming commit
+	 * control will always use values retrieved from a successful GET_CUR
+	 * request on the probe control, as required by the UVC specification.
+	 */
+	ret = uvc_get_video_ctrl(stream, probe, 1, UVC_GET_CUR);
+
+	/*
+	 * Elgato Cam Link 4k can be in a stalled state if the resolution of
+	 * the external source has changed while the firmware initializes.
+	 * Once in this state, the device is useless until it receives a
+	 * USB reset. It has even been observed that the stalled state will
+	 * continue even after unplugging the device.
+	 */
+	if (ret == -EPROTO &&
+	    usb_match_one_id(stream->dev->intf, &elgato_cam_link_4k)) {
+		dev_err(&stream->intf->dev, "Elgato Cam Link 4K firmware crash detected\n");
+		dev_err(&stream->intf->dev, "Resetting the device, unplug and replug to recover\n");
+		usb_reset_device(stream->dev->udev);
+	}
+
+	if (ret < 0)
+		return ret;
+
+	/*
+	 * Check if the default format descriptor exists. Use the first
+	 * available format otherwise.
+	 */
+	for (i = stream->nformats; i > 0; --i) {
+		format = &stream->formats[i-1];
+		if (format->index == probe->bFormatIndex)
+			break;
+	}
+
+	if (format->nframes == 0) {
+		dev_info(&stream->intf->dev,
+			 "No frame descriptor found for the default format.\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * Zero bFrameIndex might be correct. Stream-based formats (including
+	 * MPEG-2 TS and DV) do not support frames but have a dummy frame
+	 * descriptor with bFrameIndex set to zero. If the default frame
+	 * descriptor is not found, use the first available frame.
+	 */
+	for (i = format->nframes; i > 0; --i) {
+		frame = &format->frames[i-1];
+		if (frame->bFrameIndex == probe->bFrameIndex)
+			break;
+	}
+
+	probe->bFormatIndex = format->index;
+	probe->bFrameIndex = frame->bFrameIndex;
+
+	stream->def_format = format;
+	stream->cur_format = format;
+	stream->cur_frame = frame;
+
+	/* Select the video decoding function */
+	if (stream->type == V4L2_BUF_TYPE_VIDEO_CAPTURE) {
+		if (stream->dev->quirks & UVC_QUIRK_BUILTIN_ISIGHT)
+			stream->decode = uvc_video_decode_isight;
+		else if (stream->intf->num_altsetting > 1)
+			stream->decode = uvc_video_decode_isoc;
+		else
+			stream->decode = uvc_video_decode_bulk;
+	} else {
+		if (stream->intf->num_altsetting == 1)
+			stream->decode = uvc_video_encode_bulk;
+		else {
+			dev_info(&stream->intf->dev,
+				 "Isochronous endpoints are not supported for video output devices.\n");
+			return -EINVAL;
+		}
+	}
+
+	/* Prepare asynchronous work items. */
+	for_each_uvc_urb(uvc_urb, stream)
+		INIT_WORK(&uvc_urb->work, uvc_video_copy_data_work);
+
+	return 0;
+}
+
+int uvc_video_start_streaming(struct uvc_streaming *stream)
+{
+	int ret;
+
+	ret = uvc_video_clock_init(stream);
+	if (ret < 0)
+		return ret;
+
+	/* Commit the streaming parameters. */
+	ret = uvc_commit_video(stream, &stream->ctrl);
+	if (ret < 0)
+		goto error_commit;
+
+	ret = uvc_video_start_transfer(stream, GFP_KERNEL);
+	if (ret < 0)
+		goto error_video;
+
+	return 0;
+
+error_video:
+	usb_set_interface(stream->dev->udev, stream->intfnum, 0);
+error_commit:
+	uvc_video_clock_cleanup(stream);
+
+	return ret;
+}
+
+void uvc_video_stop_streaming(struct uvc_streaming *stream)
+{
+	uvc_video_stop_transfer(stream, 1);
+
+	if (stream->intf->num_altsetting > 1) {
+		usb_set_interface(stream->dev->udev, stream->intfnum, 0);
+	} else {
+		/*
+		 * UVC doesn't specify how to inform a bulk-based device
+		 * when the video stream is stopped. Windows sends a
+		 * CLEAR_FEATURE(HALT) request to the video streaming
+		 * bulk endpoint, mimic the same behaviour.
+		 */
+		unsigned int epnum = stream->header.bEndpointAddress
+				   & USB_ENDPOINT_NUMBER_MASK;
+		unsigned int dir = stream->header.bEndpointAddress
+				 & USB_ENDPOINT_DIR_MASK;
+		unsigned int pipe;
+
+		pipe = usb_sndbulkpipe(stream->dev->udev, epnum) | dir;
+		usb_clear_halt(stream->dev->udev, pipe);
+	}
+
+	uvc_video_clock_cleanup(stream);
+}
diff --git a/drivers/media/usb/uvc/uvcvideo.h b/drivers/media/usb/uvc/uvcvideo.h
new file mode 100644
index 000000000..6fb0a78b1
--- /dev/null
+++ b/drivers/media/usb/uvc/uvcvideo.h
@@ -0,0 +1,811 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _USB_VIDEO_H_
+#define _USB_VIDEO_H_
+
+#ifndef __KERNEL__
+#error "The uvcvideo.h header is deprecated, use linux/uvcvideo.h instead."
+#endif /* __KERNEL__ */
+
+#include <linux/atomic.h>
+#include <linux/kernel.h>
+#include <linux/poll.h>
+#include <linux/usb.h>
+#include <linux/usb/video.h>
+#include <linux/uvcvideo.h>
+#include <linux/videodev2.h>
+#include <linux/workqueue.h>
+#include <media/media-device.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-event.h>
+#include <media/v4l2-fh.h>
+#include <media/videobuf2-v4l2.h>
+
+/* --------------------------------------------------------------------------
+ * UVC constants
+ */
+
+#define UVC_TERM_INPUT			0x0000
+#define UVC_TERM_OUTPUT			0x8000
+#define UVC_TERM_DIRECTION(term)	((term)->type & 0x8000)
+
+#define UVC_ENTITY_TYPE(entity)		((entity)->type & 0x7fff)
+#define UVC_ENTITY_IS_UNIT(entity)	(((entity)->type & 0xff00) == 0)
+#define UVC_ENTITY_IS_TERM(entity)	(((entity)->type & 0xff00) != 0)
+#define UVC_ENTITY_IS_ITERM(entity) \
+	(UVC_ENTITY_IS_TERM(entity) && \
+	((entity)->type & 0x8000) == UVC_TERM_INPUT)
+#define UVC_ENTITY_IS_OTERM(entity) \
+	(UVC_ENTITY_IS_TERM(entity) && \
+	((entity)->type & 0x8000) == UVC_TERM_OUTPUT)
+
+#define UVC_EXT_GPIO_UNIT		0x7ffe
+#define UVC_EXT_GPIO_UNIT_ID		0x100
+
+/* ------------------------------------------------------------------------
+ * Driver specific constants.
+ */
+
+#define DRIVER_VERSION		"1.1.1"
+
+/* Number of isochronous URBs. */
+#define UVC_URBS		5
+/* Maximum number of packets per URB. */
+#define UVC_MAX_PACKETS		32
+
+#define UVC_CTRL_CONTROL_TIMEOUT	5000
+#define UVC_CTRL_STREAMING_TIMEOUT	5000
+
+/* Maximum allowed number of control mappings per device */
+#define UVC_MAX_CONTROL_MAPPINGS	1024
+#define UVC_MAX_CONTROL_MENU_ENTRIES	32
+
+/* Devices quirks */
+#define UVC_QUIRK_STATUS_INTERVAL	0x00000001
+#define UVC_QUIRK_PROBE_MINMAX		0x00000002
+#define UVC_QUIRK_PROBE_EXTRAFIELDS	0x00000004
+#define UVC_QUIRK_BUILTIN_ISIGHT	0x00000008
+#define UVC_QUIRK_STREAM_NO_FID		0x00000010
+#define UVC_QUIRK_IGNORE_SELECTOR_UNIT	0x00000020
+#define UVC_QUIRK_FIX_BANDWIDTH		0x00000080
+#define UVC_QUIRK_PROBE_DEF		0x00000100
+#define UVC_QUIRK_RESTRICT_FRAME_RATE	0x00000200
+#define UVC_QUIRK_RESTORE_CTRLS_ON_INIT	0x00000400
+#define UVC_QUIRK_FORCE_Y8		0x00000800
+#define UVC_QUIRK_FORCE_BPP		0x00001000
+#define UVC_QUIRK_WAKE_AUTOSUSPEND	0x00002000
+
+/* Format flags */
+#define UVC_FMT_FLAG_COMPRESSED		0x00000001
+#define UVC_FMT_FLAG_STREAM		0x00000002
+
+/* ------------------------------------------------------------------------
+ * Structures.
+ */
+
+struct gpio_desc;
+struct sg_table;
+struct uvc_device;
+
+/*
+ * TODO: Put the most frequently accessed fields at the beginning of
+ * structures to maximize cache efficiency.
+ */
+struct uvc_control_info {
+	struct list_head mappings;
+
+	u8 entity[16];
+	u8 index;	/* Bit index in bmControls */
+	u8 selector;
+
+	u16 size;
+	u32 flags;
+};
+
+struct uvc_control_mapping {
+	struct list_head list;
+	struct list_head ev_subs;
+
+	u32 id;
+	char *name;
+	u8 entity[16];
+	u8 selector;
+
+	u8 size;
+	u8 offset;
+	enum v4l2_ctrl_type v4l2_type;
+	u32 data_type;
+
+	const u32 *menu_mapping;
+	const char (*menu_names)[UVC_MENU_NAME_LEN];
+	unsigned long menu_mask;
+
+	u32 master_id;
+	s32 master_manual;
+	u32 slave_ids[2];
+
+	s32 (*get)(struct uvc_control_mapping *mapping, u8 query,
+		   const u8 *data);
+	void (*set)(struct uvc_control_mapping *mapping, s32 value,
+		    u8 *data);
+};
+
+struct uvc_control {
+	struct uvc_entity *entity;
+	struct uvc_control_info info;
+
+	u8 index;	/* Used to match the uvc_control entry with a uvc_control_info. */
+	u8 dirty:1,
+	   loaded:1,
+	   modified:1,
+	   cached:1,
+	   initialized:1;
+
+	u8 *uvc_data;
+
+	struct uvc_fh *handle;	/* File handle that last changed the control. */
+};
+
+/*
+ * The term 'entity' refers to both UVC units and UVC terminals.
+ *
+ * The type field is either the terminal type (wTerminalType in the terminal
+ * descriptor), or the unit type (bDescriptorSubtype in the unit descriptor).
+ * As the bDescriptorSubtype field is one byte long, the type value will
+ * always have a null MSB for units. All terminal types defined by the UVC
+ * specification have a non-null MSB, so it is safe to use the MSB to
+ * differentiate between units and terminals as long as the descriptor parsing
+ * code makes sure terminal types have a non-null MSB.
+ *
+ * For terminals, the type's most significant bit stores the terminal
+ * direction (either UVC_TERM_INPUT or UVC_TERM_OUTPUT). The type field should
+ * always be accessed with the UVC_ENTITY_* macros and never directly.
+ */
+
+#define UVC_ENTITY_FLAG_DEFAULT		(1 << 0)
+
+struct uvc_entity {
+	struct list_head list;		/* Entity as part of a UVC device. */
+	struct list_head chain;		/* Entity as part of a video device chain. */
+	unsigned int flags;
+
+	/*
+	 * Entities exposed by the UVC device use IDs 0-255, extra entities
+	 * implemented by the driver (such as the GPIO entity) use IDs 256 and
+	 * up.
+	 */
+	u16 id;
+	u16 type;
+	char name[64];
+	u8 guid[16];
+
+	/* Media controller-related fields. */
+	struct video_device *vdev;
+	struct v4l2_subdev subdev;
+	unsigned int num_pads;
+	unsigned int num_links;
+	struct media_pad *pads;
+
+	union {
+		struct {
+			u16 wObjectiveFocalLengthMin;
+			u16 wObjectiveFocalLengthMax;
+			u16 wOcularFocalLength;
+			u8  bControlSize;
+			u8  *bmControls;
+		} camera;
+
+		struct {
+			u8  bControlSize;
+			u8  *bmControls;
+			u8  bTransportModeSize;
+			u8  *bmTransportModes;
+		} media;
+
+		struct {
+		} output;
+
+		struct {
+			u16 wMaxMultiplier;
+			u8  bControlSize;
+			u8  *bmControls;
+			u8  bmVideoStandards;
+		} processing;
+
+		struct {
+		} selector;
+
+		struct {
+			u8  bNumControls;
+			u8  bControlSize;
+			u8  *bmControls;
+			u8  *bmControlsType;
+		} extension;
+
+		struct {
+			u8  bControlSize;
+			u8  *bmControls;
+			struct gpio_desc *gpio_privacy;
+			int irq;
+		} gpio;
+	};
+
+	u8 bNrInPins;
+	u8 *baSourceID;
+
+	int (*get_info)(struct uvc_device *dev, struct uvc_entity *entity,
+			u8 cs, u8 *caps);
+	int (*get_cur)(struct uvc_device *dev, struct uvc_entity *entity,
+		       u8 cs, void *data, u16 size);
+
+	unsigned int ncontrols;
+	struct uvc_control *controls;
+};
+
+struct uvc_frame {
+	u8  bFrameIndex;
+	u8  bmCapabilities;
+	u16 wWidth;
+	u16 wHeight;
+	u32 dwMinBitRate;
+	u32 dwMaxBitRate;
+	u32 dwMaxVideoFrameBufferSize;
+	u8  bFrameIntervalType;
+	u32 dwDefaultFrameInterval;
+	const u32 *dwFrameInterval;
+};
+
+struct uvc_format {
+	u8 type;
+	u8 index;
+	u8 bpp;
+	enum v4l2_colorspace colorspace;
+	enum v4l2_xfer_func xfer_func;
+	enum v4l2_ycbcr_encoding ycbcr_enc;
+	u32 fcc;
+	u32 flags;
+
+	unsigned int nframes;
+	const struct uvc_frame *frames;
+};
+
+struct uvc_streaming_header {
+	u8 bNumFormats;
+	u8 bEndpointAddress;
+	u8 bTerminalLink;
+	u8 bControlSize;
+	u8 *bmaControls;
+	/* The following fields are used by input headers only. */
+	u8 bmInfo;
+	u8 bStillCaptureMethod;
+	u8 bTriggerSupport;
+	u8 bTriggerUsage;
+};
+
+enum uvc_buffer_state {
+	UVC_BUF_STATE_IDLE	= 0,
+	UVC_BUF_STATE_QUEUED	= 1,
+	UVC_BUF_STATE_ACTIVE	= 2,
+	UVC_BUF_STATE_READY	= 3,
+	UVC_BUF_STATE_DONE	= 4,
+	UVC_BUF_STATE_ERROR	= 5,
+};
+
+struct uvc_buffer {
+	struct vb2_v4l2_buffer buf;
+	struct list_head queue;
+
+	enum uvc_buffer_state state;
+	unsigned int error;
+
+	void *mem;
+	unsigned int length;
+	unsigned int bytesused;
+
+	u32 pts;
+
+	/* Asynchronous buffer handling. */
+	struct kref ref;
+};
+
+#define UVC_QUEUE_DISCONNECTED		(1 << 0)
+#define UVC_QUEUE_DROP_CORRUPTED	(1 << 1)
+
+struct uvc_video_queue {
+	struct vb2_queue queue;
+	struct mutex mutex;			/* Protects queue */
+
+	unsigned int flags;
+	unsigned int buf_used;
+
+	spinlock_t irqlock;			/* Protects irqqueue */
+	struct list_head irqqueue;
+};
+
+struct uvc_video_chain {
+	struct uvc_device *dev;
+	struct list_head list;
+
+	struct list_head entities;		/* All entities */
+	struct uvc_entity *processing;		/* Processing unit */
+	struct uvc_entity *selector;		/* Selector unit */
+
+	struct mutex ctrl_mutex;		/* Protects ctrl.info */
+
+	struct v4l2_prio_state prio;		/* V4L2 priority state */
+	u32 caps;				/* V4L2 chain-wide caps */
+	u8 ctrl_class_bitmap;			/* Bitmap of valid classes */
+};
+
+struct uvc_stats_frame {
+	unsigned int size;		/* Number of bytes captured */
+	unsigned int first_data;	/* Index of the first non-empty packet */
+
+	unsigned int nb_packets;	/* Number of packets */
+	unsigned int nb_empty;		/* Number of empty packets */
+	unsigned int nb_invalid;	/* Number of packets with an invalid header */
+	unsigned int nb_errors;		/* Number of packets with the error bit set */
+
+	unsigned int nb_pts;		/* Number of packets with a PTS timestamp */
+	unsigned int nb_pts_diffs;	/* Number of PTS differences inside a frame */
+	unsigned int last_pts_diff;	/* Index of the last PTS difference */
+	bool has_initial_pts;		/* Whether the first non-empty packet has a PTS */
+	bool has_early_pts;		/* Whether a PTS is present before the first non-empty packet */
+	u32 pts;			/* PTS of the last packet */
+
+	unsigned int nb_scr;		/* Number of packets with a SCR timestamp */
+	unsigned int nb_scr_diffs;	/* Number of SCR.STC differences inside a frame */
+	u16 scr_sof;			/* SCR.SOF of the last packet */
+	u32 scr_stc;			/* SCR.STC of the last packet */
+};
+
+struct uvc_stats_stream {
+	ktime_t start_ts;		/* Stream start timestamp */
+	ktime_t stop_ts;		/* Stream stop timestamp */
+
+	unsigned int nb_frames;		/* Number of frames */
+
+	unsigned int nb_packets;	/* Number of packets */
+	unsigned int nb_empty;		/* Number of empty packets */
+	unsigned int nb_invalid;	/* Number of packets with an invalid header */
+	unsigned int nb_errors;		/* Number of packets with the error bit set */
+
+	unsigned int nb_pts_constant;	/* Number of frames with constant PTS */
+	unsigned int nb_pts_early;	/* Number of frames with early PTS */
+	unsigned int nb_pts_initial;	/* Number of frames with initial PTS */
+
+	unsigned int nb_scr_count_ok;	/* Number of frames with at least one SCR per non empty packet */
+	unsigned int nb_scr_diffs_ok;	/* Number of frames with varying SCR.STC */
+	unsigned int scr_sof_count;	/* STC.SOF counter accumulated since stream start */
+	unsigned int scr_sof;		/* STC.SOF of the last packet */
+	unsigned int min_sof;		/* Minimum STC.SOF value */
+	unsigned int max_sof;		/* Maximum STC.SOF value */
+};
+
+#define UVC_METADATA_BUF_SIZE 10240
+
+/**
+ * struct uvc_copy_op: Context structure to schedule asynchronous memcpy
+ *
+ * @buf: active buf object for this operation
+ * @dst: copy destination address
+ * @src: copy source address
+ * @len: copy length
+ */
+struct uvc_copy_op {
+	struct uvc_buffer *buf;
+	void *dst;
+	const __u8 *src;
+	size_t len;
+};
+
+/**
+ * struct uvc_urb - URB context management structure
+ *
+ * @urb: the URB described by this context structure
+ * @stream: UVC streaming context
+ * @buffer: memory storage for the URB
+ * @dma: Allocated DMA handle
+ * @sgt: sgt_table with the urb locations in memory
+ * @async_operations: counter to indicate the number of copy operations
+ * @copy_operations: work descriptors for asynchronous copy operations
+ * @work: work queue entry for asynchronous decode
+ */
+struct uvc_urb {
+	struct urb *urb;
+	struct uvc_streaming *stream;
+
+	char *buffer;
+	dma_addr_t dma;
+	struct sg_table *sgt;
+
+	unsigned int async_operations;
+	struct uvc_copy_op copy_operations[UVC_MAX_PACKETS];
+	struct work_struct work;
+};
+
+struct uvc_streaming {
+	struct list_head list;
+	struct uvc_device *dev;
+	struct video_device vdev;
+	struct uvc_video_chain *chain;
+	atomic_t active;
+
+	struct usb_interface *intf;
+	int intfnum;
+	u16 maxpsize;
+
+	struct uvc_streaming_header header;
+	enum v4l2_buf_type type;
+
+	unsigned int nformats;
+	const struct uvc_format *formats;
+
+	struct uvc_streaming_control ctrl;
+	const struct uvc_format *def_format;
+	const struct uvc_format *cur_format;
+	const struct uvc_frame *cur_frame;
+
+	/*
+	 * Protect access to ctrl, cur_format, cur_frame and hardware video
+	 * probe control.
+	 */
+	struct mutex mutex;
+
+	/* Buffers queue. */
+	unsigned int frozen : 1;
+	struct uvc_video_queue queue;
+	struct workqueue_struct *async_wq;
+	void (*decode)(struct uvc_urb *uvc_urb, struct uvc_buffer *buf,
+		       struct uvc_buffer *meta_buf);
+
+	struct {
+		struct video_device vdev;
+		struct uvc_video_queue queue;
+		u32 format;
+	} meta;
+
+	/* Context data used by the bulk completion handler. */
+	struct {
+		u8 header[256];
+		unsigned int header_size;
+		int skip_payload;
+		u32 payload_size;
+		u32 max_payload_size;
+	} bulk;
+
+	struct uvc_urb uvc_urb[UVC_URBS];
+	unsigned int urb_size;
+
+	u32 sequence;
+	u8 last_fid;
+
+	/* debugfs */
+	struct dentry *debugfs_dir;
+	struct {
+		struct uvc_stats_frame frame;
+		struct uvc_stats_stream stream;
+	} stats;
+
+	/* Timestamps support. */
+	struct uvc_clock {
+		struct uvc_clock_sample {
+			u32 dev_stc;
+			u16 dev_sof;
+			u16 host_sof;
+			ktime_t host_time;
+		} *samples;
+
+		unsigned int head;
+		unsigned int count;
+		unsigned int size;
+
+		u16 last_sof;
+		u16 sof_offset;
+
+		u8 last_scr[6];
+
+		spinlock_t lock;
+	} clock;
+};
+
+#define for_each_uvc_urb(uvc_urb, uvc_streaming) \
+	for ((uvc_urb) = &(uvc_streaming)->uvc_urb[0]; \
+	     (uvc_urb) < &(uvc_streaming)->uvc_urb[UVC_URBS]; \
+	     ++(uvc_urb))
+
+static inline u32 uvc_urb_index(const struct uvc_urb *uvc_urb)
+{
+	return uvc_urb - &uvc_urb->stream->uvc_urb[0];
+}
+
+struct uvc_device_info {
+	u32	quirks;
+	u32	meta_format;
+	u16	uvc_version;
+	const struct uvc_control_mapping **mappings;
+};
+
+struct uvc_status_streaming {
+	u8	button;
+} __packed;
+
+struct uvc_status_control {
+	u8	bSelector;
+	u8	bAttribute;
+	u8	bValue[11];
+} __packed;
+
+struct uvc_status {
+	u8	bStatusType;
+	u8	bOriginator;
+	u8	bEvent;
+	union {
+		struct uvc_status_control control;
+		struct uvc_status_streaming streaming;
+	};
+} __packed;
+
+struct uvc_device {
+	struct usb_device *udev;
+	struct usb_interface *intf;
+	unsigned long warnings;
+	u32 quirks;
+	int intfnum;
+	char name[32];
+
+	const struct uvc_device_info *info;
+
+	struct mutex lock;		/* Protects users */
+	unsigned int users;
+	atomic_t nmappings;
+
+	/* Video control interface */
+#ifdef CONFIG_MEDIA_CONTROLLER
+	struct media_device mdev;
+#endif
+	struct v4l2_device vdev;
+	u16 uvc_version;
+	u32 clock_frequency;
+
+	struct list_head entities;
+	struct list_head chains;
+
+	/* Video Streaming interfaces */
+	struct list_head streams;
+	struct kref ref;
+
+	/* Status Interrupt Endpoint */
+	struct usb_host_endpoint *int_ep;
+	struct urb *int_urb;
+	struct uvc_status *status;
+	bool flush_status;
+
+	struct input_dev *input;
+	char input_phys[64];
+
+	struct uvc_ctrl_work {
+		struct work_struct work;
+		struct urb *urb;
+		struct uvc_video_chain *chain;
+		struct uvc_control *ctrl;
+		const void *data;
+	} async_ctrl;
+
+	struct uvc_entity *gpio_unit;
+};
+
+enum uvc_handle_state {
+	UVC_HANDLE_PASSIVE	= 0,
+	UVC_HANDLE_ACTIVE	= 1,
+};
+
+struct uvc_fh {
+	struct v4l2_fh vfh;
+	struct uvc_video_chain *chain;
+	struct uvc_streaming *stream;
+	enum uvc_handle_state state;
+};
+
+struct uvc_driver {
+	struct usb_driver driver;
+};
+
+/* ------------------------------------------------------------------------
+ * Debugging, printing and logging
+ */
+
+#define UVC_DBG_PROBE		(1 << 0)
+#define UVC_DBG_DESCR		(1 << 1)
+#define UVC_DBG_CONTROL		(1 << 2)
+#define UVC_DBG_FORMAT		(1 << 3)
+#define UVC_DBG_CAPTURE		(1 << 4)
+#define UVC_DBG_CALLS		(1 << 5)
+#define UVC_DBG_FRAME		(1 << 7)
+#define UVC_DBG_SUSPEND		(1 << 8)
+#define UVC_DBG_STATUS		(1 << 9)
+#define UVC_DBG_VIDEO		(1 << 10)
+#define UVC_DBG_STATS		(1 << 11)
+#define UVC_DBG_CLOCK		(1 << 12)
+
+#define UVC_WARN_MINMAX		0
+#define UVC_WARN_PROBE_DEF	1
+#define UVC_WARN_XU_GET_RES	2
+
+extern unsigned int uvc_clock_param;
+extern unsigned int uvc_no_drop_param;
+extern unsigned int uvc_dbg_param;
+extern unsigned int uvc_timeout_param;
+extern unsigned int uvc_hw_timestamps_param;
+
+#define uvc_dbg(_dev, flag, fmt, ...)					\
+do {									\
+	if (uvc_dbg_param & UVC_DBG_##flag)				\
+		dev_printk(KERN_DEBUG, &(_dev)->udev->dev, fmt,		\
+			   ##__VA_ARGS__);				\
+} while (0)
+
+#define uvc_dbg_cont(flag, fmt, ...)					\
+do {									\
+	if (uvc_dbg_param & UVC_DBG_##flag)				\
+		pr_cont(fmt, ##__VA_ARGS__);				\
+} while (0)
+
+#define uvc_warn_once(_dev, warn, fmt, ...)				\
+do {									\
+	if (!test_and_set_bit(warn, &(_dev)->warnings))			\
+		dev_info(&(_dev)->udev->dev, fmt, ##__VA_ARGS__);	\
+} while (0)
+
+/* --------------------------------------------------------------------------
+ * Internal functions.
+ */
+
+/* Core driver */
+extern struct uvc_driver uvc_driver;
+
+struct uvc_entity *uvc_entity_by_id(struct uvc_device *dev, int id);
+
+/* Video buffers queue management. */
+int uvc_queue_init(struct uvc_video_queue *queue, enum v4l2_buf_type type,
+		   int drop_corrupted);
+void uvc_queue_release(struct uvc_video_queue *queue);
+int uvc_request_buffers(struct uvc_video_queue *queue,
+			struct v4l2_requestbuffers *rb);
+int uvc_query_buffer(struct uvc_video_queue *queue,
+		     struct v4l2_buffer *v4l2_buf);
+int uvc_create_buffers(struct uvc_video_queue *queue,
+		       struct v4l2_create_buffers *v4l2_cb);
+int uvc_queue_buffer(struct uvc_video_queue *queue,
+		     struct media_device *mdev,
+		     struct v4l2_buffer *v4l2_buf);
+int uvc_export_buffer(struct uvc_video_queue *queue,
+		      struct v4l2_exportbuffer *exp);
+int uvc_dequeue_buffer(struct uvc_video_queue *queue,
+		       struct v4l2_buffer *v4l2_buf, int nonblocking);
+int uvc_queue_streamon(struct uvc_video_queue *queue, enum v4l2_buf_type type);
+int uvc_queue_streamoff(struct uvc_video_queue *queue, enum v4l2_buf_type type);
+void uvc_queue_cancel(struct uvc_video_queue *queue, int disconnect);
+struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
+					 struct uvc_buffer *buf);
+struct uvc_buffer *uvc_queue_get_current_buffer(struct uvc_video_queue *queue);
+void uvc_queue_buffer_release(struct uvc_buffer *buf);
+int uvc_queue_mmap(struct uvc_video_queue *queue,
+		   struct vm_area_struct *vma);
+__poll_t uvc_queue_poll(struct uvc_video_queue *queue, struct file *file,
+			poll_table *wait);
+#ifndef CONFIG_MMU
+unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
+					  unsigned long pgoff);
+#endif
+int uvc_queue_allocated(struct uvc_video_queue *queue);
+static inline int uvc_queue_streaming(struct uvc_video_queue *queue)
+{
+	return vb2_is_streaming(&queue->queue);
+}
+
+static inline struct uvc_streaming *
+uvc_queue_to_stream(struct uvc_video_queue *queue)
+{
+	return container_of(queue, struct uvc_streaming, queue);
+}
+
+/* V4L2 interface */
+extern const struct v4l2_ioctl_ops uvc_ioctl_ops;
+extern const struct v4l2_file_operations uvc_fops;
+
+/* Media controller */
+int uvc_mc_register_entities(struct uvc_video_chain *chain);
+void uvc_mc_cleanup_entity(struct uvc_entity *entity);
+
+/* Video */
+int uvc_video_init(struct uvc_streaming *stream);
+int uvc_video_suspend(struct uvc_streaming *stream);
+int uvc_video_resume(struct uvc_streaming *stream, int reset);
+int uvc_video_start_streaming(struct uvc_streaming *stream);
+void uvc_video_stop_streaming(struct uvc_streaming *stream);
+int uvc_probe_video(struct uvc_streaming *stream,
+		    struct uvc_streaming_control *probe);
+int uvc_query_ctrl(struct uvc_device *dev, u8 query, u8 unit,
+		   u8 intfnum, u8 cs, void *data, u16 size);
+void uvc_video_clock_update(struct uvc_streaming *stream,
+			    struct vb2_v4l2_buffer *vbuf,
+			    struct uvc_buffer *buf);
+int uvc_meta_register(struct uvc_streaming *stream);
+
+int uvc_register_video_device(struct uvc_device *dev,
+			      struct uvc_streaming *stream,
+			      struct video_device *vdev,
+			      struct uvc_video_queue *queue,
+			      enum v4l2_buf_type type,
+			      const struct v4l2_file_operations *fops,
+			      const struct v4l2_ioctl_ops *ioctl_ops);
+
+/* Status */
+int uvc_status_init(struct uvc_device *dev);
+void uvc_status_unregister(struct uvc_device *dev);
+void uvc_status_cleanup(struct uvc_device *dev);
+int uvc_status_start(struct uvc_device *dev, gfp_t flags);
+void uvc_status_stop(struct uvc_device *dev);
+
+/* Controls */
+extern const struct uvc_control_mapping uvc_ctrl_power_line_mapping_limited;
+extern const struct uvc_control_mapping uvc_ctrl_power_line_mapping_uvc11;
+extern const struct v4l2_subscribed_event_ops uvc_ctrl_sub_ev_ops;
+
+int uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
+			struct v4l2_queryctrl *v4l2_ctrl);
+int uvc_query_v4l2_menu(struct uvc_video_chain *chain,
+			struct v4l2_querymenu *query_menu);
+
+int uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
+			 const struct uvc_control_mapping *mapping);
+int uvc_ctrl_init_device(struct uvc_device *dev);
+void uvc_ctrl_cleanup_device(struct uvc_device *dev);
+int uvc_ctrl_restore_values(struct uvc_device *dev);
+bool uvc_ctrl_status_event_async(struct urb *urb, struct uvc_video_chain *chain,
+				 struct uvc_control *ctrl, const u8 *data);
+void uvc_ctrl_status_event(struct uvc_video_chain *chain,
+			   struct uvc_control *ctrl, const u8 *data);
+
+int uvc_ctrl_begin(struct uvc_video_chain *chain);
+int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
+		      struct v4l2_ext_controls *ctrls);
+static inline int uvc_ctrl_commit(struct uvc_fh *handle,
+				  struct v4l2_ext_controls *ctrls)
+{
+	return __uvc_ctrl_commit(handle, 0, ctrls);
+}
+static inline int uvc_ctrl_rollback(struct uvc_fh *handle)
+{
+	return __uvc_ctrl_commit(handle, 1, NULL);
+}
+
+int uvc_ctrl_get(struct uvc_video_chain *chain, struct v4l2_ext_control *xctrl);
+int uvc_ctrl_set(struct uvc_fh *handle, struct v4l2_ext_control *xctrl);
+int uvc_ctrl_is_accessible(struct uvc_video_chain *chain, u32 v4l2_id,
+			   const struct v4l2_ext_controls *ctrls,
+			   unsigned long ioctl);
+
+int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
+		      struct uvc_xu_control_query *xqry);
+
+/* Utility functions */
+struct usb_host_endpoint *uvc_find_endpoint(struct usb_host_interface *alts,
+					    u8 epaddr);
+u16 uvc_endpoint_max_bpi(struct usb_device *dev, struct usb_host_endpoint *ep);
+
+/* Quirks support */
+void uvc_video_decode_isight(struct uvc_urb *uvc_urb,
+			     struct uvc_buffer *buf,
+			     struct uvc_buffer *meta_buf);
+
+/* debugfs and statistics */
+void uvc_debugfs_init(void);
+void uvc_debugfs_cleanup(void);
+void uvc_debugfs_init_stream(struct uvc_streaming *stream);
+void uvc_debugfs_cleanup_stream(struct uvc_streaming *stream);
+
+size_t uvc_video_stats_dump(struct uvc_streaming *stream, char *buf,
+			    size_t size);
+
+#endif