uvcvideo.h

Go to the documentation of this file.

// 2009/7/1 Opt Corporation
//   change Private V4L2 control identifiers.
//   add XU_COMMAND definition.

#ifndef _USB_VIDEO_H_
#define _USB_VIDEO_H_

#include <linux/kernel.h>
#include <linux/videodev2.h>
#include <linux/usb/video.h>
#include <linux/uvcvideo.h>

/* Compatibility */
#include "uvc_compat.h"

/*
 * Private V4L2 control identifiers.
 */
/*
#define V4L2_CID_BACKLIGHT_COMPENSATION         (V4L2_CID_PRIVATE_BASE+0)
#define V4L2_CID_POWER_LINE_FREQUENCY           (V4L2_CID_PRIVATE_BASE+1)
#define V4L2_CID_SHARPNESS                      (V4L2_CID_PRIVATE_BASE+2)
#define V4L2_CID_HUE_AUTO                       (V4L2_CID_PRIVATE_BASE+3)

#define V4L2_CID_FOCUS_AUTO                     (V4L2_CID_PRIVATE_BASE+4)
#define V4L2_CID_FOCUS_ABSOLUTE                 (V4L2_CID_PRIVATE_BASE+5)
#define V4L2_CID_FOCUS_RELATIVE                 (V4L2_CID_PRIVATE_BASE+6)

#define V4L2_CID_PAN_RELATIVE                   (V4L2_CID_PRIVATE_BASE+7)
#define V4L2_CID_TILT_RELATIVE                  (V4L2_CID_PRIVATE_BASE+8)
#define V4L2_CID_PANTILT_RESET                  (V4L2_CID_PRIVATE_BASE+9)

#define V4L2_CID_EXPOSURE_AUTO                  (V4L2_CID_PRIVATE_BASE+10)
#define V4L2_CID_EXPOSURE_ABSOLUTE              (V4L2_CID_PRIVATE_BASE+11)

#define V4L2_CID_WHITE_BALANCE_TEMPERATURE_AUTO (V4L2_CID_PRIVATE_BASE+12)
#define V4L2_CID_WHITE_BALANCE_TEMPERATURE      (V4L2_CID_PRIVATE_BASE+13)

#define V4L2_CID_PRIVATE_LAST                   V4L2_CID_WHITE_BALANCE_TEMPERATURE
*/
#define V4L2_CID_PANTILT_RESET                  (V4L2_CID_PRIVATE_BASE+9)
#define V4L2_CID_WHITE_BALANCE_TEMPERATURE_AUTO V4L2_CID_AUTO_WHITE_BALANCE
#define V4L2_CID_ZOOM_RELATIVE                  (V4L2_CID_CAMERA_CLASS_BASE+14)

#define UVC_GUID_UVC_EXTENSION  {0x4e, 0x4d, 0x33, 0x30, 0x01, 0x7a, 0xce, 0x41, \
                                 0x80, 0x53, 0x5b, 0x7f, 0x3f, 0xb7, 0x61, 0x99}

#define XU_UNDEFINED                       0x00
#define XU_FIRMWARE_VERSION_CONTROL        0x01
#define XU_FLASH_PARAMETER_CONTROL         0x02
#define XU_FLIP_SCREEN_CONTROL             0x03
#define XU_SMALL_HEMISPHERE_CONTROL        0x04
#define XU_ANALOG_VIDEO_STANDARD_CONTROL   0x05
#define XU_MEDIAN_FILTER_CONTROL           0x07
#define XU_PUSH_BUTTON_CONTROL             0x08
#define XU_PENDING_PTZR_CONTROL            0x0B
#define XU_AUTO_PAN_SPEED_CONTROL          0x0C
#define XU_JPEG_QUALITY_CONTROL            0x0D
#define XU_SERIAL_ID_CONTROL               0x0E
#define XU_INFO_DISPLAY_CONTROL            0x0F
#define XU_CAPTURE_FPS_CONTROL             0x10
#define XU_ACTUAL_FPS_CONTROL              0x11
#define XU_LENS_TYPE_CONTROL               0x12
#define XU_PAN_ABSOLUTE_CONTROL            0x13
#define XU_TILT_ABSOLUTE_CONTROL           0x14
#define XU_ROLL_ABSOLUTE_CONTROL           0x15
#define XU_ZOOM_ABSOLUTE_CONTROL           0x16
#define XU_LOCATION_ABSOLUTE_CONTROL       0x17
#define XU_GAIN_ABSOLUTE_CONTROL           0x1E

/* Control flags */
#define UVC_CONTROL_SET_CUR     (1 << 0)
#define UVC_CONTROL_GET_CUR     (1 << 1)

#ifdef __KERNEL__

/* --------------------------------------------------------------------------
 * UVC constants
 */

#define SC_UNDEFINED                    0x00
#define SC_VIDEOCONTROL                 0x01
#define SC_VIDEOSTREAMING               0x02
#define SC_VIDEO_INTERFACE_COLLECTION   0x03

#define PC_PROTOCOL_UNDEFINED           0x00

#define CS_UNDEFINED                    0x20
#define CS_DEVICE                       0x21
#define CS_CONFIGURATION                0x22
#define CS_STRING                       0x23
#define CS_INTERFACE                    0x24
#define CS_ENDPOINT                     0x25

/* VideoControl class specific interface descriptor */
#define VC_DESCRIPTOR_UNDEFINED         0x00
#define VC_HEADER                       0x01
#define VC_INPUT_TERMINAL               0x02
#define VC_OUTPUT_TERMINAL              0x03
#define VC_SELECTOR_UNIT                0x04
#define VC_PROCESSING_UNIT              0x05
#define VC_EXTENSION_UNIT               0x06

/* VideoStreaming class specific interface descriptor */
#define VS_UNDEFINED                    0x00
#define VS_INPUT_HEADER                 0x01
#define VS_OUTPUT_HEADER                0x02
#define VS_STILL_IMAGE_FRAME            0x03
#define VS_FORMAT_UNCOMPRESSED          0x04
#define VS_FRAME_UNCOMPRESSED           0x05
#define VS_FORMAT_MJPEG                 0x06
#define VS_FRAME_MJPEG                  0x07
#define VS_FORMAT_MPEG2TS               0x0a
#define VS_FORMAT_DV                    0x0c
#define VS_COLORFORMAT                  0x0d
#define VS_FORMAT_FRAME_BASED           0x10
#define VS_FRAME_FRAME_BASED            0x11
#define VS_FORMAT_STREAM_BASED          0x12

/* Endpoint type */
#define EP_UNDEFINED                    0x00
#define EP_GENERAL                      0x01
#define EP_ENDPOINT                     0x02
#define EP_INTERRUPT                    0x03

/* Request codes */
#define RC_UNDEFINED                    0x00
#define SET_CUR                         0x01
#define GET_CUR                         0x81
#define GET_MIN                         0x82
#define GET_MAX                         0x83
#define GET_RES                         0x84
#define GET_LEN                         0x85
#define GET_INFO                        0x86
#define GET_DEF                         0x87

/* VideoControl interface controls */
#define VC_CONTROL_UNDEFINED            0x00
#define VC_VIDEO_POWER_MODE_CONTROL     0x01
#define VC_REQUEST_ERROR_CODE_CONTROL   0x02

/* Terminal controls */
#define TE_CONTROL_UNDEFINED            0x00

/* Selector Unit controls */
#define SU_CONTROL_UNDEFINED            0x00
#define SU_INPUT_SELECT_CONTROL         0x01

/* Camera Terminal controls */
#define CT_CONTROL_UNDEFINED                            0x00
#define CT_SCANNING_MODE_CONTROL                        0x01
#define CT_AE_MODE_CONTROL                              0x02
#define CT_AE_PRIORITY_CONTROL                          0x03
#define CT_EXPOSURE_TIME_ABSOLUTE_CONTROL               0x04
#define CT_EXPOSURE_TIME_RELATIVE_CONTROL               0x05
#define CT_FOCUS_ABSOLUTE_CONTROL                       0x06
#define CT_FOCUS_RELATIVE_CONTROL                       0x07
#define CT_FOCUS_AUTO_CONTROL                           0x08
#define CT_IRIS_ABSOLUTE_CONTROL                        0x09
#define CT_IRIS_RELATIVE_CONTROL                        0x0a
#define CT_ZOOM_ABSOLUTE_CONTROL                        0x0b
#define CT_ZOOM_RELATIVE_CONTROL                        0x0c
#define CT_PANTILT_ABSOLUTE_CONTROL                     0x0d
#define CT_PANTILT_RELATIVE_CONTROL                     0x0e
#define CT_ROLL_ABSOLUTE_CONTROL                        0x0f
#define CT_ROLL_RELATIVE_CONTROL                        0x10
#define CT_PRIVACY_CONTROL                              0x11

/* Processing Unit controls */
#define PU_CONTROL_UNDEFINED                            0x00
#define PU_BACKLIGHT_COMPENSATION_CONTROL               0x01
#define PU_BRIGHTNESS_CONTROL                           0x02
#define PU_CONTRAST_CONTROL                             0x03
#define PU_GAIN_CONTROL                                 0x04
#define PU_POWER_LINE_FREQUENCY_CONTROL                 0x05
#define PU_HUE_CONTROL                                  0x06
#define PU_SATURATION_CONTROL                           0x07
#define PU_SHARPNESS_CONTROL                            0x08
#define PU_GAMMA_CONTROL                                0x09
#define PU_WHITE_BALANCE_TEMPERATURE_CONTROL            0x0a
#define PU_WHITE_BALANCE_TEMPERATURE_AUTO_CONTROL       0x0b
#define PU_WHITE_BALANCE_COMPONENT_CONTROL              0x0c
#define PU_WHITE_BALANCE_COMPONENT_AUTO_CONTROL         0x0d
#define PU_DIGITAL_MULTIPLIER_CONTROL                   0x0e
#define PU_DIGITAL_MULTIPLIER_LIMIT_CONTROL             0x0f
#define PU_HUE_AUTO_CONTROL                             0x10
#define PU_ANALOG_VIDEO_STANDARD_CONTROL                0x11
#define PU_ANALOG_LOCK_STATUS_CONTROL                   0x12

#define LXU_MOTOR_PANTILT_RELATIVE_CONTROL              0x01
#define LXU_MOTOR_PANTILT_RESET_CONTROL                 0x02

/* VideoStreaming interface controls */
#define VS_CONTROL_UNDEFINED            0x00
#define VS_PROBE_CONTROL                0x01
#define VS_COMMIT_CONTROL               0x02
#define VS_STILL_PROBE_CONTROL          0x03
#define VS_STILL_COMMIT_CONTROL         0x04
#define VS_STILL_IMAGE_TRIGGER_CONTROL  0x05
#define VS_STREAM_ERROR_CODE_CONTROL    0x06
#define VS_GENERATE_KEY_FRAME_CONTROL   0x07
#define VS_UPDATE_FRAME_SEGMENT_CONTROL 0x08
#define VS_SYNC_DELAY_CONTROL           0x09

#define TT_VENDOR_SPECIFIC              0x0100
#define TT_STREAMING                    0x0101

/* Input Terminal types */
#define ITT_VENDOR_SPECIFIC             0x0200
#define ITT_CAMERA                      0x0201
#define ITT_MEDIA_TRANSPORT_INPUT       0x0202

/* Output Terminal types */
#define OTT_VENDOR_SPECIFIC             0x0300
#define OTT_DISPLAY                     0x0301
#define OTT_MEDIA_TRANSPORT_OUTPUT      0x0302

#define EXTERNAL_VENDOR_SPECIFIC        0x0400
#define COMPOSITE_CONNECTOR             0x0401
#define SVIDEO_CONNECTOR                0x0402
#define COMPONENT_CONNECTOR             0x0403

#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)     ((entity->type & 0xff00) == ITT_VENDOR_SPECIFIC)
#define UVC_ENTITY_IS_OTERM(entity)     ((entity->type & 0xff00) == OTT_VENDOR_SPECIFIC)

/* ------------------------------------------------------------------------
 * GUIDs
 */
#define UVC_GUID_UVC_CAMERA     {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \
                                 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01}
#define UVC_GUID_UVC_OUTPUT     {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \
                                 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x02}
#define UVC_GUID_UVC_PROCESSING {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \
                                 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01}
#define UVC_GUID_UVC_SELECTOR   {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \
                                 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x02}

#define UVC_GUID_LOGITECH_XU1   {0x82, 0x06, 0x61, 0x63, 0x70, 0x50, 0xab, 0x49, \
                                 0xb8, 0xcc, 0xb3, 0x85, 0x5e, 0x8d, 0x22, 0x1d}
#define UVC_GUID_LOGITECH_XU2   {0x82, 0x06, 0x61, 0x63, 0x70, 0x50, 0xab, 0x49, \
                                 0xb8, 0xcc, 0xb3, 0x85, 0x5e, 0x8d, 0x22, 0x1e}
#define UVC_GUID_LOGITECH_XU3   {0x82, 0x06, 0x61, 0x63, 0x70, 0x50, 0xab, 0x49, \
                                 0xb8, 0xcc, 0xb3, 0x85, 0x5e, 0x8d, 0x22, 0x1f}
#define UVC_GUID_LOGITECH_MOTOR {0x82, 0x06, 0x61, 0x63, 0x70, 0x50, 0xab, 0x49, \
                                 0xb8, 0xcc, 0xb3, 0x85, 0x5e, 0x8d, 0x22, 0x56}
#define UVC_GUID_LOGITECH_DEV_INFO \
                                {0x82, 0x06, 0x61, 0x63, 0x70, 0x50, 0xab, 0x49, \
                                 0xb8, 0xcc, 0xb3, 0x85, 0x5e, 0x8d, 0x22, 0x1e}

#define UVC_GUID_FORMAT_MJPEG   {0x4d, 0x4a, 0x50, 0x47, 0x00, 0x00, 0x10, 0x00, \
                                 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_YUY2    {0x59, 0x55, 0x59, 0x32, 0x00, 0x00, 0x10, 0x00, \
                                 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_NV12    {0x4e, 0x56, 0x31, 0x32, 0x00, 0x00, 0x10, 0x00, \
                                 0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}


/* ------------------------------------------------------------------------
 * Driver specific constants.
 */

#define DRIVER_VERSION_NUMBER   KERNEL_VERSION(0, 1, 0)

/* Number of isochronous URBs. */
#define UVC_URBS                5
/* Maximum number of packets per isochronous URB. */
#define UVC_MAX_ISO_PACKETS     40
/* Maximum frame size in bytes, for sanity checking. */
#define UVC_MAX_FRAME_SIZE      (16*1024*1024)
/* Maximum number of video buffers. */
#define UVC_MAX_VIDEO_BUFFERS   32

#define UVC_CTRL_TIMEOUT        300

/* Devices quirks */
#define UVC_QUIRK_STATUS_INTERVAL       0x00000001

/* ------------------------------------------------------------------------
 * Structures.
 */

struct uvc_device;

/* TODO: Put the most frequently accessed fields at the beginning of
 * structures to maximize cache efficiency.
 */
struct uvc_streaming_control {
        __u16 bmHint;
        __u8  bFormatIndex;
        __u8  bFrameIndex;
        __u32 dwFrameInterval;
        __u16 wKeyFrameRate;
        __u16 wPFrameRate;
        __u16 wCompQuality;
        __u16 wCompWindowSize;
        __u16 wDelay;
        __u32 dwMaxVideoFrameSize;
        __u32 dwMaxPayloadTransferSize;
        __u32 dwClockFrequency;
        __u8  bmFramingInfo;
        __u8  bPreferedVersion;
        __u8  bMinVersion;
        __u8  bMaxVersion;
};

struct uvc_menu_info {
        __u32 index;
        __u8 name[32];
};

struct uvc_control_info {
        struct list_head list;
        struct list_head mappings;

        __u8 entity[16];
        __u8 index;
        __u8 selector;

        __u8 size;
        __u8 flags;
};

/* Data types for UVC control data */
enum uvc_control_data_type {
        UVC_CTRL_DATA_TYPE_RAW = 0,
        UVC_CTRL_DATA_TYPE_SIGNED,
        UVC_CTRL_DATA_TYPE_UNSIGNED,
        UVC_CTRL_DATA_TYPE_BOOLEAN,
        UVC_CTRL_DATA_TYPE_ENUM,
        UVC_CTRL_DATA_TYPE_BITMASK,
};

struct uvc_control_mapping {
        struct list_head list;

        struct uvc_control_info *ctrl;

        __u32 id;
        __u8 name[32];
        __u8 entity[16];
        __u8 selector;

        __u8 size;
        __u8 offset;
        enum v4l2_ctrl_type v4l2_type;
        enum uvc_control_data_type data_type;

        struct uvc_menu_info *menu_info;
        __u32 menu_count;
};

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;

        __u8 *data;
};

struct uvc_format_desc {
        __u8 guid[16];
        __u32 fcc;
};

/* 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 sur terminal types have a non-null MSB.
 */

struct uvc_entity {
        struct list_head list;

        __u8 id;
        __u16 type;
        char name[64];

        union {
                struct {
                        __u16 wObjectiveFocalLengthMin;
                        __u16 wObjectiveFocalLengthMax;
                        __u16 wOcularFocalLength;
                        __u8  bControlSize;
                        __u8  *bmControls;
                } camera;

                struct {
                        __u8  bSourceID;
                } output;

                struct {
                        __u8  bSourceID;
                        __u16 wMaxMultiplier;
                        __u8  bControlSize;
                        __u8  *bmControls;
                        __u8  bmVideoStandards;
                } processing;

                struct {
                        __u8  bNrInPins;
                        __u8  *baSourceID;
                } selector;

                struct {
                        __u8  guidExtensionCode[16];
                        __u8  bNumControls;
                        __u8  bNrInPins;
                        __u8  *baSourceID;
                        __u8  bControlSize;
                        __u8  *bmControls;
                        __u8  *bmControlsType;
                } extension;
        };

        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;
        __u32 *dwFrameInterval;
};

struct uvc_format {
        __u8 type;
        __u8 index;
        __u8 bpp;
        __u8 colorspace;
        __u32 fcc;
        __u32 flags;

        char name[32];

        unsigned int nframes;
        struct uvc_frame *frame;
};

struct uvc_input_header {
        __u8 bNumFormats;
        __u8 bEndpointAddress;
        __u8 bmInfo;
        __u8 bTerminalLink;
        __u8 bStillCaptureMethod;
        __u8 bTriggerSupport;
        __u8 bTriggerUsage;
        __u8 bControlSize;
        __u8 *bmaControls;
};

struct uvc_output_header {
};

struct uvc_streaming {
        struct list_head list;

        struct usb_interface *intf;
        int intfnum;
        __u16 maxpsize;

        union {
                struct uvc_input_header input;
                struct uvc_output_header output;
        };

        unsigned int nformats;
        struct uvc_format *format;

        struct uvc_streaming_control ctrl;
        struct uvc_format *cur_format;
        struct uvc_frame *cur_frame;

        struct mutex mutex;
};

enum uvc_stream_state {
        UVC_STREAM_OFF = 0,
        UVC_STREAM_INTERRUPT = 1,
        UVC_STREAM_ON = 2,
};

enum uvc_buffer_state {
        UVC_BUF_STATE_IDLE       = 0,
        UVC_BUF_STATE_QUEUED     = 1,
        UVC_BUF_STATE_ACTIVE     = 2,
        UVC_BUF_STATE_DONE       = 3,
        UVC_BUF_STATE_ERROR      = 4,
};

struct uvc_buffer {
        unsigned int size;
        unsigned long vma_use_count;
        struct list_head stream;

        /* Touched by interrupt handler. */
        struct v4l2_buffer buf;
        struct list_head queue;
        wait_queue_head_t wait;
        enum uvc_buffer_state state;
};

struct uvc_video_queue {
        void *mem;
        unsigned int streaming;
        __u32 sequence;
        __u8 last_fid;

        unsigned int count;
        struct uvc_buffer buffer[UVC_MAX_VIDEO_BUFFERS];
        struct mutex mutex;
        spinlock_t irqlock;

        struct list_head mainqueue;
        struct list_head irqqueue;
};

struct uvc_video_device {
        struct uvc_device *dev;
        struct video_device *vdev;
        atomic_t active;

        enum uvc_stream_state stream;

        struct uvc_entity *iterm;
        struct uvc_entity *oterm;
        struct uvc_entity *processing;
        struct uvc_entity *extension[8];
        struct mutex ctrl_mutex;

        struct uvc_video_queue queue;

        struct uvc_streaming *streaming;

        struct urb *urb[UVC_URBS];
        char *urb_buffer[UVC_URBS];
};

enum uvc_device_state {
        UVC_DEV_DISCONNECTED = 1,
};

struct uvc_device {
        struct usb_device *udev;
        struct usb_interface *intf;
        __u32 quirks;
        int intfnum;

        enum uvc_device_state state;
        struct kref kref;
        struct list_head list;

        /* Video control interface */
        __u16 uvc_version;
        __u32 clock_frequency;

        struct list_head entities;

        struct uvc_video_device video;

        /* Status Interrupt Endpoint */
        struct usb_host_endpoint *int_ep;
        struct urb *int_urb;
        __u8 status[16];

        /* Video Streaming interfaces */
        struct list_head streaming;
};

enum uvc_handle_state {
        UVC_HANDLE_PASSIVE      = 0,
        UVC_HANDLE_ACTIVE       = 1,
};

struct uvc_fh {
        struct uvc_video_device *device;
        enum uvc_handle_state state;
};

struct uvc_driver {
        struct usb_driver driver;

        struct mutex open_mutex;        /* protects from open/disconnect race */

        struct list_head devices;       /* struct uvc_device list */
        struct list_head controls;      /* struct uvc_control_info list */
        struct mutex ctrl_mutex;        /* protects controls and devices lists */
};

/* ------------------------------------------------------------------------
 * Debugging, printing and logging
 */

#define UVC_TRACE_PROBE         (1 << 0)
#define UVC_TRACE_DESCR         (1 << 1)
#define UVC_TRACE_CONTROL       (1 << 2)
#define UVC_TRACE_FORMAT        (1 << 3)
#define UVC_TRACE_CAPTURE       (1 << 4)
#define UVC_TRACE_CALLS         (1 << 5)
#define UVC_TRACE_IOCTL         (1 << 6)
#define UVC_TRACE_FRAME         (1 << 7)

extern unsigned int uvc_trace_param;

#define uvc_trace(flag, msg...) \
        do { \
                if (uvc_trace_param & flag) \
                        printk(KERN_DEBUG "uvcvideo: " msg); \
        } while(0)

#define uvc_printk(level, msg...) \
        printk(level "uvcvideo: " msg)

#define UVC_GUID_FORMAT "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x"
#define UVC_GUID_ARGS(guid) \
        (guid)[3],  (guid)[2],  (guid)[1],  (guid)[0], \
        (guid)[5],  (guid)[4], \
        (guid)[7],  (guid)[6], \
        (guid)[8],  (guid)[9], \
        (guid)[10], (guid)[11], (guid)[12], \
        (guid)[13], (guid)[14], (guid)[15]

/* --------------------------------------------------------------------------
 * Internal functions.
 */

/* Core driver */
extern struct uvc_driver uvc_driver;
extern void uvc_delete(struct kref *kref);

/* Video buffers queue management. */
extern void uvc_queue_init(struct uvc_video_queue *queue);
extern int uvc_alloc_buffers(struct uvc_video_queue *queue,
                unsigned int nbuffers, unsigned int buflength);
extern int uvc_free_buffers(struct uvc_video_queue *queue);
extern void uvc_query_buffer(struct uvc_buffer *buf,
                struct v4l2_buffer *v4l2_buf);
extern int uvc_queue_buffer(struct uvc_video_queue *queue,
                struct v4l2_buffer *v4l2_buf);
extern int uvc_dequeue_buffer(struct uvc_video_queue *queue,
                struct v4l2_buffer *v4l2_buf, int nonblocking);
extern int uvc_queue_enable(struct uvc_video_queue *queue, int enable);
extern void uvc_queue_cancel(struct uvc_video_queue *queue);
extern struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
                struct uvc_buffer *buf);

/* V4L2 interface */
extern struct file_operations uvc_fops;

/* Video */
extern int uvc_video_init(struct uvc_video_device *video);
extern int uvc_video_enable(struct uvc_video_device *video, int enable);
extern int uvc_probe_video(struct uvc_video_device *video,
                struct uvc_streaming_control *probe);
extern int uvc_query_ctrl(struct uvc_device *dev, __u8 query, __u8 unit,
                __u8 intfnum, __u8 cs, void *data, __u16 size);
extern int uvc_set_video_ctrl(struct uvc_video_device *video,
                struct uvc_streaming_control *ctrl, int probe);
extern int uvc_init_status(struct uvc_device *dev);

/* Controls */
extern struct uvc_control *uvc_find_control(struct uvc_video_device *video,
                __u32 v4l2_id, struct uvc_control_mapping **mapping);
extern int uvc_query_v4l2_ctrl(struct uvc_video_device *video,
                struct v4l2_queryctrl *v4l2_ctrl);

extern void uvc_ctrl_add_info(struct uvc_control_info *info);
extern int uvc_ctrl_init_device(struct uvc_device *dev);
extern void uvc_ctrl_cleanup_device(struct uvc_device *dev);
extern void uvc_ctrl_init(void);

extern int uvc_ctrl_begin(struct uvc_video_device *video);
extern int __uvc_ctrl_commit(struct uvc_video_device *video, int rollback);
static inline int uvc_ctrl_commit(struct uvc_video_device *video)
{
        return __uvc_ctrl_commit(video, 0);
}
static inline int uvc_ctrl_rollback(struct uvc_video_device *video)
{
        return __uvc_ctrl_commit(video, 1);
}

extern int uvc_ctrl_get(struct uvc_video_device *video,
                struct v4l2_ext_control *xctrl);
extern int uvc_ctrl_set(struct uvc_video_device *video,
                struct v4l2_ext_control *xctrl);

/* Utility functions */
extern void uvc_simplify_fraction(uint32_t *numerator, uint32_t *denominator,
                unsigned int n_terms, unsigned int threshold);
extern uint32_t uvc_fraction_to_interval(uint32_t numerator,
                uint32_t denominator);
extern struct usb_host_endpoint *uvc_find_endpoint(
                struct usb_host_interface *alts, __u8 epaddr);

#endif /* __KERNEL__ */

#endif