uvcvideo.h

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#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/kernel.h>
#include <linux/poll.h>
#include <linux/usb.h>
#include <linux/usb/video.h>
#include <linux/uvcvideo.h>
#include <linux/videodev2.h>
#include <media/media-device.h>
#include <media/v4l2-device.h>
#include <media/v4l2-event.h>
#include <media/v4l2-fh.h>
#include <media/videobuf2-core.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)


/* ------------------------------------------------------------------------
 * 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_MEDIA_TRANSPORT_INPUT \
    {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, \
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03}
#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_FORMAT_MJPEG \
    { 'M',  'J',  'P',  'G', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_YUY2 \
    { 'Y',  'U',  'Y',  '2', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_YUY2_ISIGHT \
    { 'Y',  'U',  'Y',  '2', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0x00, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_NV12 \
    { 'N',  'V',  '1',  '2', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_YV12 \
    { 'Y',  'V',  '1',  '2', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_I420 \
    { 'I',  '4',  '2',  '0', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_UYVY \
    { 'U',  'Y',  'V',  'Y', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_Y800 \
    { 'Y',  '8',  '0',  '0', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_Y8 \
    { 'Y',  '8',  ' ',  ' ', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_Y10 \
    { 'Y',  '1',  '0',  ' ', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_Y12 \
    { 'Y',  '1',  '2',  ' ', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_Y16 \
    { 'Y',  '1',  '6',  ' ', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_BY8 \
    { 'B',  'Y',  '8',  ' ', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_RGBP \
    { 'R',  'G',  'B',  'P', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}
#define UVC_GUID_FORMAT_M420 \
    { 'M',  '4',  '2',  '0', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}

#define UVC_GUID_FORMAT_H264 \
    { 'H',  '2',  '6',  '4', 0x00, 0x00, 0x10, 0x00, \
     0x80, 0x00, 0x00, 0xaa, 0x00, 0x38, 0x9b, 0x71}

/* ------------------------------------------------------------------------
 * 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
/* Maximum number of video buffers. */
#define UVC_MAX_VIDEO_BUFFERS   32
/* Maximum status buffer size in bytes of interrupt URB. */
#define UVC_MAX_STATUS_SIZE 16

#define UVC_CTRL_CONTROL_TIMEOUT    300
#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

/* Format flags */
#define UVC_FMT_FLAG_COMPRESSED     0x00000001
#define UVC_FMT_FLAG_STREAM     0x00000002

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

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

    __u8 size;
    __u8 offset;
    enum v4l2_ctrl_type v4l2_type;
    __u32 data_type;

    struct uvc_menu_info *menu_info;
    __u32 menu_count;

    __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_format_desc {
    char *name;
    __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 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.
 */

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. */
    __u8 id;
    __u16 type;
    char name[64];

    /* 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  guidExtensionCode[16];
            __u8  bNumControls;
            __u8  bControlSize;
            __u8  *bmControls;
            __u8  *bmControlsType;
        } extension;
    };

    __u8 bNrInPins;
    __u8 *baSourceID;

    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_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_buffer buf;
    struct list_head queue;

    enum uvc_buffer_state state;
    unsigned int error;

    void *mem;
    unsigned int length;
    unsigned int bytesused;

    u32 pts;
};

#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 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 {
    struct timespec start_ts;   /* Stream start timestamp */
    struct timespec 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 */
};

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;
    struct uvc_format *format;

    struct uvc_streaming_control ctrl;
    struct uvc_format *cur_format;
    struct uvc_frame *cur_frame;
    /* Protect access to ctrl, cur_format, cur_frame and hardware video
     * probe control.
     */
    struct mutex mutex;

    /* Buffers queue. */
    unsigned int frozen : 1;
    struct uvc_video_queue queue;
    void (*decode) (struct urb *urb, struct uvc_streaming *video,
            struct uvc_buffer *buf);

    /* 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 urb *urb[UVC_URBS];
    char *urb_buffer[UVC_URBS];
    dma_addr_t urb_dma[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;
            struct timespec host_ts;
            u16 host_sof;
        } *samples;

        unsigned int head;
        unsigned int count;
        unsigned int size;

        u16 last_sof;
        u16 sof_offset;

        spinlock_t lock;
    } clock;
};

enum uvc_device_state {
    UVC_DEV_DISCONNECTED = 1,
};

struct uvc_device {
    struct usb_device *udev;
    struct usb_interface *intf;
    unsigned long warnings;
    __u32 quirks;
    int intfnum;
    char name[32];

    enum uvc_device_state state;
    atomic_t 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;
    atomic_t nstreams;

    /* Status Interrupt Endpoint */
    struct usb_host_endpoint *int_ep;
    struct urb *int_urb;
    __u8 *status;
    struct input_dev *input;
    char input_phys[64];
};

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_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)
#define UVC_TRACE_SUSPEND   (1 << 8)
#define UVC_TRACE_STATUS    (1 << 9)
#define UVC_TRACE_VIDEO     (1 << 10)
#define UVC_TRACE_STATS     (1 << 11)
#define UVC_TRACE_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_trace_param;
extern unsigned int uvc_timeout_param;

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

#define uvc_warn_once(dev, warn, msg...) \
    do { \
        if (!test_and_set_bit(warn, &dev->warnings)) \
            printk(KERN_INFO "uvcvideo: " msg); \
    } while (0)

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

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

/* Core driver */
extern struct uvc_driver uvc_driver;

extern struct uvc_entity *uvc_entity_by_id(struct uvc_device *dev, int id);

/* Video buffers queue management. */
extern int uvc_queue_init(struct uvc_video_queue *queue,
        enum v4l2_buf_type type, int drop_corrupted);
extern int uvc_alloc_buffers(struct uvc_video_queue *queue,
        struct v4l2_requestbuffers *rb);
extern void uvc_free_buffers(struct uvc_video_queue *queue);
extern int uvc_query_buffer(struct uvc_video_queue *queue,
        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, int disconnect);
extern struct uvc_buffer *uvc_queue_next_buffer(struct uvc_video_queue *queue,
        struct uvc_buffer *buf);
extern int uvc_queue_mmap(struct uvc_video_queue *queue,
        struct vm_area_struct *vma);
extern unsigned int uvc_queue_poll(struct uvc_video_queue *queue,
        struct file *file, poll_table *wait);
#ifndef CONFIG_MMU
extern unsigned long uvc_queue_get_unmapped_area(struct uvc_video_queue *queue,
        unsigned long pgoff);
#endif
extern 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);
}

/* V4L2 interface */
extern const struct v4l2_file_operations uvc_fops;

/* Media controller */
extern int uvc_mc_register_entities(struct uvc_video_chain *chain);
extern void uvc_mc_cleanup_entity(struct uvc_entity *entity);

/* Video */
extern int uvc_video_init(struct uvc_streaming *stream);
extern int uvc_video_suspend(struct uvc_streaming *stream);
extern int uvc_video_resume(struct uvc_streaming *stream, int reset);
extern int uvc_video_enable(struct uvc_streaming *stream, int enable);
extern int uvc_probe_video(struct uvc_streaming *stream,
        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);
void uvc_video_clock_update(struct uvc_streaming *stream,
                struct v4l2_buffer *v4l2_buf,
                struct uvc_buffer *buf);

/* Status */
extern int uvc_status_init(struct uvc_device *dev);
extern void uvc_status_cleanup(struct uvc_device *dev);
extern int uvc_status_start(struct uvc_device *dev);
extern void uvc_status_stop(struct uvc_device *dev);
extern int uvc_status_suspend(struct uvc_device *dev);
extern int uvc_status_resume(struct uvc_device *dev);

/* Controls */
extern const struct v4l2_subscribed_event_ops uvc_ctrl_sub_ev_ops;

extern int uvc_query_v4l2_ctrl(struct uvc_video_chain *chain,
        struct v4l2_queryctrl *v4l2_ctrl);
extern int uvc_query_v4l2_menu(struct uvc_video_chain *chain,
        struct v4l2_querymenu *query_menu);

extern int uvc_ctrl_add_mapping(struct uvc_video_chain *chain,
        const struct uvc_control_mapping *mapping);
extern int uvc_ctrl_init_device(struct uvc_device *dev);
extern void uvc_ctrl_cleanup_device(struct uvc_device *dev);
extern int uvc_ctrl_resume_device(struct uvc_device *dev);

extern int uvc_ctrl_begin(struct uvc_video_chain *chain);
extern int __uvc_ctrl_commit(struct uvc_fh *handle, int rollback,
            const struct v4l2_ext_control *xctrls,
            unsigned int xctrls_count);
static inline int uvc_ctrl_commit(struct uvc_fh *handle,
            const struct v4l2_ext_control *xctrls,
            unsigned int xctrls_count)
{
    return __uvc_ctrl_commit(handle, 0, xctrls, xctrls_count);
}
static inline int uvc_ctrl_rollback(struct uvc_fh *handle)
{
    return __uvc_ctrl_commit(handle, 1, NULL, 0);
}

extern int uvc_ctrl_get(struct uvc_video_chain *chain,
        struct v4l2_ext_control *xctrl);
extern int uvc_ctrl_set(struct uvc_video_chain *chain,
        struct v4l2_ext_control *xctrl);

extern int uvc_xu_ctrl_query(struct uvc_video_chain *chain,
        struct uvc_xu_control_query *xqry);

/* 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);

/* Quirks support */
void uvc_video_decode_isight(struct urb *urb, struct uvc_streaming *stream,
        struct uvc_buffer *buf);

/* debugfs and statistics */
int uvc_debugfs_init(void);
void uvc_debugfs_cleanup(void);
int 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