Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 2223 insertions, 0 deletions

diff --git a/kernel/drivers/media/usb/uvc/uvc_ctrl.c b/kernel/drivers/media/usb/uvc/uvc_ctrl.c
new file mode 100644
index 000000000..3e59b288b
--- /dev/null
+++ b/kernel/drivers/media/usb/uvc/uvc_ctrl.c
@@ -0,0 +1,2223 @@
+/*
+ *      uvc_ctrl.c  --  USB Video Class driver - Controls
+ *
+ *      Copyright (C) 2005-2010
+ *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
+ *
+ *      This program is free software; you can redistribute it and/or modify
+ *      it under the terms of the GNU General Public License as published by
+ *      the Free Software Foundation; either version 2 of the License, or
+ *      (at your option) any later version.
+ *
+ */
+
+#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/videodev2.h>
+#include <linux/vmalloc.h>
+#include <linux/wait.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 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,
+	},
+	{
+		.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,
+	},
+};
+
+static struct uvc_menu_info power_line_frequency_controls[] = {
+	{ 0, "Disabled" },
+	{ 1, "50 Hz" },
+	{ 2, "60 Hz" },
+};
+
+static struct uvc_menu_info exposure_auto_controls[] = {
+	{ 2, "Auto Mode" },
+	{ 1, "Manual Mode" },
+	{ 4, "Shutter Priority Mode" },
+	{ 8, "Aperture Priority Mode" },
+};
+
+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 struct uvc_control_mapping uvc_ctrl_mappings[] = {
+	{
+		.id		= V4L2_CID_BRIGHTNESS,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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_POWER_LINE_FREQUENCY,
+		.name		= "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_info	= power_line_frequency_controls,
+		.menu_count	= ARRAY_SIZE(power_line_frequency_controls),
+	},
+	{
+		.id		= V4L2_CID_HUE_AUTO,
+		.name		= "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,
+		.name		= "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_info	= exposure_auto_controls,
+		.menu_count	= ARRAY_SIZE(exposure_auto_controls),
+		.slave_ids	= { V4L2_CID_EXPOSURE_ABSOLUTE, },
+	},
+	{
+		.id		= V4L2_CID_EXPOSURE_AUTO_PRIORITY,
+		.name		= "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,
+		.name		= "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,
+		.name		= "White Balance Temperature, Auto",
+		.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,
+		.name		= "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,
+		.name		= "White Balance Component, Auto",
+		.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,
+		.name		= "White Balance Blue Component",
+		.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,
+		.name		= "White Balance Red Component",
+		.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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+		.name		= "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,
+	},
+};
+
+/* ------------------------------------------------------------------------
+ * 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;
+
+	for (; bits > 0; data++) {
+		__u8 byte = *data & mask;
+		value |= offset > 0 ? (byte >> offset) : (byte << (-offset));
+		bits -= 8 - (offset > 0 ? offset : 0);
+		offset -= 8;
+		mask = (1 << bits) - 1;
+	}
+
+	/* 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 const __u8 uvc_processing_guid[16] = UVC_GUID_UVC_PROCESSING;
+static const __u8 uvc_camera_guid[16] = UVC_GUID_UVC_CAMERA;
+static const __u8 uvc_media_transport_input_guid[16] =
+	UVC_GUID_UVC_MEDIA_TRANSPORT_INPUT;
+
+static int uvc_entity_match_guid(const struct uvc_entity *entity,
+	const __u8 guid[16])
+{
+	switch (UVC_ENTITY_TYPE(entity)) {
+	case UVC_ITT_CAMERA:
+		return memcmp(uvc_camera_guid, guid, 16) == 0;
+
+	case UVC_ITT_MEDIA_TRANSPORT_INPUT:
+		return memcmp(uvc_media_transport_input_guid, guid, 16) == 0;
+
+	case UVC_VC_PROCESSING_UNIT:
+		return memcmp(uvc_processing_guid, guid, 16) == 0;
+
+	case UVC_VC_EXTENSION_UNIT:
+		return memcmp(entity->extension.guidExtensionCode,
+			      guid, 16) == 0;
+
+	default:
+		return 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_trace(UVC_TRACE_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 int __uvc_ctrl_get(struct uvc_video_chain *chain,
+	struct uvc_control *ctrl, struct uvc_control_mapping *mapping,
+	s32 *value)
+{
+	struct uvc_menu_info *menu;
+	unsigned int i;
+	int ret;
+
+	if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) == 0)
+		return -EACCES;
+
+	if (!ctrl->loaded) {
+		ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR, ctrl->entity->id,
+				chain->dev->intfnum, ctrl->info.selector,
+				uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
+				ctrl->info.size);
+		if (ret < 0)
+			return ret;
+
+		ctrl->loaded = 1;
+	}
+
+	*value = mapping->get(mapping, UVC_GET_CUR,
+		uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT));
+
+	if (mapping->v4l2_type == V4L2_CTRL_TYPE_MENU) {
+		menu = mapping->menu_info;
+		for (i = 0; i < mapping->menu_count; ++i, ++menu) {
+			if (menu->value == *value) {
+				*value = i;
+				break;
+			}
+		}
+	}
+
+	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;
+	struct uvc_menu_info *menu;
+	unsigned int i;
+
+	memset(v4l2_ctrl, 0, sizeof *v4l2_ctrl);
+	v4l2_ctrl->id = mapping->id;
+	v4l2_ctrl->type = mapping->v4l2_type;
+	strlcpy(v4l2_ctrl->name, mapping->name, 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 = 0;
+		v4l2_ctrl->maximum = mapping->menu_count - 1;
+		v4l2_ctrl->step = 1;
+
+		menu = mapping->menu_info;
+		for (i = 0; i < mapping->menu_count; ++i, ++menu) {
+			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;
+
+	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;
+
+	ctrl = uvc_find_control(chain, v4l2_ctrl->id, &mapping);
+	if (ctrl == NULL) {
+		ret = -EINVAL;
+		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 straighforward if done well.
+ * Most of the UVC controls exist in V4L2, and can be mapped directly. Some
+ * must be grouped (for instance the Red Balance, Blue Balance and Do White
+ * Balance V4L2 controls use the White Balance Component UVC control) or
+ * otherwise translated. The approach we take here is to use a translation
+ * table for the controls that can be mapped directly, and handle the others
+ * manually.
+ */
+int uvc_query_v4l2_menu(struct uvc_video_chain *chain,
+	struct v4l2_querymenu *query_menu)
+{
+	struct uvc_menu_info *menu_info;
+	struct uvc_control_mapping *mapping;
+	struct uvc_control *ctrl;
+	u32 index = query_menu->index;
+	u32 id = query_menu->id;
+	int ret;
+
+	memset(query_menu, 0, sizeof(*query_menu));
+	query_menu->id = id;
+	query_menu->index = index;
+
+	ret = mutex_lock_interruptible(&chain->ctrl_mutex);
+	if (ret < 0)
+		return -ERESTARTSYS;
+
+	ctrl = uvc_find_control(chain, query_menu->id, &mapping);
+	if (ctrl == NULL || mapping->v4l2_type != V4L2_CTRL_TYPE_MENU) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	if (query_menu->index >= mapping->menu_count) {
+		ret = -EINVAL;
+		goto done;
+	}
+
+	menu_info = &mapping->menu_info[query_menu->index];
+
+	if (mapping->data_type == UVC_CTRL_DATA_TYPE_BITMASK &&
+	    (ctrl->info.flags & UVC_CTRL_FLAG_GET_RES)) {
+		s32 bitmap;
+
+		if (!ctrl->cached) {
+			ret = uvc_ctrl_populate_cache(chain, ctrl);
+			if (ret < 0)
+				goto done;
+		}
+
+		bitmap = mapping->get(mapping, UVC_GET_RES,
+				      uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES));
+		if (!(bitmap & menu_info->value)) {
+			ret = -EINVAL;
+			goto done;
+		}
+	}
+
+	strlcpy(query_menu->name, menu_info->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->reserved, 0, sizeof(ev->reserved));
+	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;
+}
+
+static void uvc_ctrl_send_event(struct uvc_fh *handle,
+	struct uvc_control *ctrl, struct uvc_control_mapping *mapping,
+	s32 value, u32 changes)
+{
+	struct v4l2_subscribed_event *sev;
+	struct v4l2_event ev;
+
+	if (list_empty(&mapping->ev_subs))
+		return;
+
+	uvc_ctrl_fill_event(handle->chain, &ev, ctrl, mapping, value, changes);
+
+	list_for_each_entry(sev, &mapping->ev_subs, node) {
+		if (sev->fh && (sev->fh != &handle->vfh ||
+		    (sev->flags & V4L2_EVENT_SUB_FL_ALLOW_FEEDBACK) ||
+		    (changes & V4L2_EVENT_CTRL_CH_FLAGS)))
+			v4l2_event_queue_fh(sev->fh, &ev);
+	}
+}
+
+static void uvc_ctrl_send_slave_event(struct uvc_fh *handle,
+	struct uvc_control *master, u32 slave_id,
+	const struct v4l2_ext_control *xctrls, unsigned int xctrls_count)
+{
+	struct uvc_control_mapping *mapping = NULL;
+	struct uvc_control *ctrl = NULL;
+	u32 changes = V4L2_EVENT_CTRL_CH_FLAGS;
+	unsigned int i;
+	s32 val = 0;
+
+	/*
+	 * We can skip sending an event for the slave if the slave
+	 * is being modified in the same transaction.
+	 */
+	for (i = 0; i < xctrls_count; i++) {
+		if (xctrls[i].id == slave_id)
+			return;
+	}
+
+	__uvc_find_control(master->entity, slave_id, &mapping, &ctrl, 0);
+	if (ctrl == NULL)
+		return;
+
+	if (__uvc_ctrl_get(handle->chain, ctrl, mapping, &val) == 0)
+		changes |= V4L2_EVENT_CTRL_CH_VALUE;
+
+	uvc_ctrl_send_event(handle, ctrl, mapping, val, changes);
+}
+
+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);
+
+		for (j = 0; j < ARRAY_SIZE(mapping->slave_ids); ++j) {
+			if (!mapping->slave_ids[j])
+				break;
+			uvc_ctrl_send_slave_event(handle, ctrl,
+						  mapping->slave_ids[j],
+						  xctrls, xctrls_count);
+		}
+
+		/*
+		 * If the master is being modified in the same transaction
+		 * flags may change too.
+		 */
+		if (mapping->master_id) {
+			for (j = 0; j < xctrls_count; j++) {
+				if (xctrls[j].id == mapping->master_id) {
+					changes |= V4L2_EVENT_CTRL_CH_FLAGS;
+					break;
+				}
+			}
+		}
+
+		uvc_ctrl_send_event(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;
+
+	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);
+	list_del(&sev->node);
+	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 *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)
+			return ret;
+	}
+
+	return 0;
+}
+
+int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
+		      const struct v4l2_ext_control *xctrls,
+		      unsigned int xctrls_count)
+{
+	struct uvc_video_chain *chain = handle->chain;
+	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);
+		if (ret < 0)
+			goto done;
+	}
+
+	if (!rollback)
+		uvc_ctrl_send_events(handle, xctrls, xctrls_count);
+done:
+	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;
+
+	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_video_chain *chain,
+	struct v4l2_ext_control *xctrl)
+{
+	struct uvc_control *ctrl;
+	struct uvc_control_mapping *mapping;
+	s32 value;
+	u32 step;
+	s32 min;
+	s32 max;
+	int ret;
+
+	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 + ((u32)(xctrl->value - min) + step / 2)
+			     / 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_BOOLEAN:
+		xctrl->value = clamp(xctrl->value, 0, 1);
+		value = xctrl->value;
+		break;
+
+	case V4L2_CTRL_TYPE_MENU:
+		if (xctrl->value < 0 || xctrl->value >= mapping->menu_count)
+			return -ERANGE;
+		value = mapping->menu_info[xctrl->value].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 &&
+		    (ctrl->info.flags & UVC_CTRL_FLAG_GET_RES)) {
+			if (!ctrl->cached) {
+				ret = uvc_ctrl_populate_cache(chain, ctrl);
+				if (ret < 0)
+					return ret;
+			}
+
+			step = mapping->get(mapping, UVC_GET_RES,
+					uvc_ctrl_data(ctrl, UVC_CTRL_DATA_RES));
+			if (!(step & 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->loaded && (ctrl->info.size * 8) != mapping->size) {
+		if ((ctrl->info.flags & UVC_CTRL_FLAG_GET_CUR) == 0) {
+			memset(uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
+				0, ctrl->info.size);
+		} else {
+			ret = uvc_query_ctrl(chain->dev, UVC_GET_CUR,
+				ctrl->entity->id, chain->dev->intfnum,
+				ctrl->info.selector,
+				uvc_ctrl_data(ctrl, UVC_CTRL_DATA_CURRENT),
+				ctrl->info.size);
+			if (ret < 0)
+				return ret;
+		}
+
+		ctrl->loaded = 1;
+	}
+
+	/* 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));
+
+	ctrl->dirty = 1;
+	ctrl->modified = 1;
+	return 0;
+}
+
+/* --------------------------------------------------------------------------
+ * Dynamic controls
+ */
+
+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->extension.guidExtensionCode,
+	       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_trace(UVC_TRACE_CONTROL,
+			  "GET_LEN failed on control %pUl/%u (%d).\n",
+			   info->entity, info->selector, ret);
+		goto done;
+	}
+
+	info->size = le16_to_cpup((__le16 *)data);
+
+	/* Query the control information (GET_INFO) */
+	ret = uvc_query_ctrl(dev, UVC_GET_INFO, ctrl->entity->id, dev->intfnum,
+			     info->selector, data, 1);
+	if (ret < 0) {
+		uvc_trace(UVC_TRACE_CONTROL,
+			  "GET_INFO failed on control %pUl/%u (%d).\n",
+			  info->entity, info->selector, ret);
+		goto done;
+	}
+
+	info->flags = UVC_CTRL_FLAG_GET_MIN | UVC_CTRL_FLAG_GET_MAX
+		    | UVC_CTRL_FLAG_GET_RES | UVC_CTRL_FLAG_GET_DEF
+		    | (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);
+
+	uvc_ctrl_fixup_xu_info(dev, ctrl, info);
+
+	uvc_trace(UVC_TRACE_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_trace(UVC_TRACE_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, found = 0;
+	__u32 reqflags;
+	__u16 size;
+	__u8 *data = NULL;
+	int ret;
+
+	/* Find the extension unit. */
+	list_for_each_entry(entity, &chain->entities, chain) {
+		if (UVC_ENTITY_TYPE(entity) == UVC_VC_EXTENSION_UNIT &&
+		    entity->id == xqry->unit)
+			break;
+	}
+
+	if (entity->id != xqry->unit) {
+		uvc_trace(UVC_TRACE_CONTROL, "Extension unit %u not found.\n",
+			xqry->unit);
+		return -ENOENT;
+	}
+
+	/* Find the control and perform delayed initialization if needed. */
+	for (i = 0; i < entity->ncontrols; ++i) {
+		ctrl = &entity->controls[i];
+		if (ctrl->index == xqry->selector - 1) {
+			found = 1;
+			break;
+		}
+	}
+
+	if (!found) {
+		uvc_trace(UVC_TRACE_CONTROL, "Control %pUl/%u not found.\n",
+			entity->extension.guidExtensionCode, 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;
+
+			printk(KERN_INFO "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);
+		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)
+{
+	int ret = 0;
+
+	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 == NULL) {
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	ctrl->initialized = 1;
+
+	uvc_trace(UVC_TRACE_CONTROL, "Added control %pUl/%u to device %s "
+		"entity %u\n", ctrl->info.entity, ctrl->info.selector,
+		dev->udev->devpath, ctrl->entity->id);
+
+done:
+	if (ret < 0)
+		kfree(ctrl->uvc_data);
+	return ret;
+}
+
+/*
+ * Add a control mapping to a given control.
+ */
+static int __uvc_ctrl_add_mapping(struct uvc_device *dev,
+	struct uvc_control *ctrl, const struct uvc_control_mapping *mapping)
+{
+	struct uvc_control_mapping *map;
+	unsigned int size;
+
+	/* 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 == NULL)
+		return -ENOMEM;
+
+	INIT_LIST_HEAD(&map->ev_subs);
+
+	size = sizeof(*mapping->menu_info) * mapping->menu_count;
+	map->menu_info = kmemdup(mapping->menu_info, size, GFP_KERNEL);
+	if (map->menu_info == NULL) {
+		kfree(map);
+		return -ENOMEM;
+	}
+
+	if (map->get == NULL)
+		map->get = uvc_get_le_value;
+	if (map->set == NULL)
+		map->set = uvc_set_le_value;
+
+	list_add_tail(&map->list, &ctrl->info.mappings);
+	uvc_trace(UVC_TRACE_CONTROL,
+		"Adding mapping '%s' to control %pUl/%u.\n",
+		map->name, ctrl->info.entity, ctrl->info.selector);
+
+	return 0;
+}
+
+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_trace(UVC_TRACE_CONTROL, "Can't add mapping '%s', control "
+			"id 0x%08x is invalid.\n", mapping->name,
+			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;
+	}
+
+	list_for_each_entry(map, &ctrl->info.mappings, list) {
+		if (mapping->id == map->id) {
+			uvc_trace(UVC_TRACE_CONTROL, "Can't add mapping '%s', "
+				"control id 0x%08x already exists.\n",
+				mapping->name, 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_trace(UVC_TRACE_CONTROL, "Can't add mapping '%s', maximum "
+			"mappings count (%u) exceeded.\n", mapping->name,
+			UVC_MAX_CONTROL_MAPPINGS);
+		ret = -ENOMEM;
+		goto done;
+	}
+
+	ret = __uvc_ctrl_add_mapping(dev, 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_trace(UVC_TRACE_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_device *dev, struct uvc_control *ctrl)
+{
+	const struct uvc_control_info *info = uvc_ctrls;
+	const struct uvc_control_info *iend = info + ARRAY_SIZE(uvc_ctrls);
+	const struct uvc_control_mapping *mapping = uvc_ctrl_mappings;
+	const struct uvc_control_mapping *mend =
+		mapping + ARRAY_SIZE(uvc_ctrl_mappings);
+
+	/* 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 (; info < iend; ++info) {
+		if (uvc_entity_match_guid(ctrl->entity, info->entity) &&
+		    ctrl->index == info->index) {
+			uvc_ctrl_add_info(dev, ctrl, info);
+			break;
+		 }
+	}
+
+	if (!ctrl->initialized)
+		return;
+
+	for (; mapping < mend; ++mapping) {
+		if (uvc_entity_match_guid(ctrl->entity, mapping->entity) &&
+		    ctrl->info.selector == mapping->selector)
+			__uvc_ctrl_add_mapping(dev, ctrl, mapping);
+	}
+}
+
+/*
+ * Initialize device controls.
+ */
+int uvc_ctrl_init_device(struct uvc_device *dev)
+{
+	struct uvc_entity *entity;
+	unsigned int i;
+
+	/* Walk the entities list and instantiate controls */
+	list_for_each_entry(entity, &dev->entities, list) {
+		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;
+		}
+
+		/* Remove bogus/blacklisted controls */
+		uvc_ctrl_prune_entity(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(dev, ctrl);
+			ctrl++;
+		}
+	}
+
+	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_info);
+		kfree(mapping);
+	}
+}
+
+void uvc_ctrl_cleanup_device(struct uvc_device *dev)
+{
+	struct uvc_entity *entity;
+	unsigned int i;
+
+	/* 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);
+	}
+}