/*
 * 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, or (at your option)
 * any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#ifndef usbvideo_h
#define usbvideo_h

#include <linux/videodev.h>
#include <media/v4l2-common.h>
#include <media/v4l2-ioctl.h>
#include <linux/usb.h>
#include <linux/mutex.h>

/* Most helpful debugging aid */
#define assert(expr) ((void) ((expr) ? 0 : (err("assert failed at line %d",__LINE__))))

#define USBVIDEO_REPORT_STATS   1       /* Set to 0 to block statistics on close */

/* Bit flags (options) */
#define FLAGS_RETRY_VIDIOCSYNC          (1 << 0)
#define FLAGS_MONOCHROME                (1 << 1)
#define FLAGS_DISPLAY_HINTS             (1 << 2)
#define FLAGS_OVERLAY_STATS             (1 << 3)
#define FLAGS_FORCE_TESTPATTERN         (1 << 4)
#define FLAGS_SEPARATE_FRAMES           (1 << 5)
#define FLAGS_CLEAN_FRAMES              (1 << 6)
#define FLAGS_NO_DECODING               (1 << 7)

/* Bit flags for frames (apply to the frame where they are specified) */
#define USBVIDEO_FRAME_FLAG_SOFTWARE_CONTRAST   (1 << 0)

/* Camera capabilities (maximum) */
#define CAMERA_URB_FRAMES       32
#define CAMERA_MAX_ISO_PACKET   1023 /* 1022 actually sent by camera */
#define FRAMES_PER_DESC         (CAMERA_URB_FRAMES)
#define FRAME_SIZE_PER_DESC     (CAMERA_MAX_ISO_PACKET)

/* This macro restricts an int variable to an inclusive range */
#define RESTRICT_TO_RANGE(v,mi,ma) { if ((v) < (mi)) (v) = (mi); else if ((v) > (ma)) (v) = (ma); }

#define V4L_BYTES_PER_PIXEL     3       /* Because we produce RGB24 */

/*
 * Use this macro to construct constants for different video sizes.
 * We have to deal with different video sizes that have to be
 * configured in the device or compared against when we receive
 * a data. Normally one would define a bunch of VIDEOSIZE_x_by_y
 * #defines and that's the end of story. However this solution
 * does not allow to convert between real pixel sizes and the
 * constant (integer) value that may be used to tag a frame or
 * whatever. The set of macros below constructs videosize constants
 * from the pixel size and allows to reconstruct the pixel size
 * from the combined value later.
 */
#define VIDEOSIZE(x,y)  (((x) & 0xFFFFL) | (((y) & 0xFFFFL) << 16))
#define VIDEOSIZE_X(vs) ((vs) & 0xFFFFL)
#define VIDEOSIZE_Y(vs) (((vs) >> 16) & 0xFFFFL)
typedef unsigned long videosize_t;

/*
 * This macro checks if the camera is still operational. The 'uvd'
 * pointer must be valid, uvd->dev must be valid, we are not
 * removing the device and the device has not erred on us.
 */
#define CAMERA_IS_OPERATIONAL(uvd) (\
        (uvd != NULL) && \
        ((uvd)->dev != NULL) && \
        ((uvd)->last_error == 0) && \
        (!(uvd)->remove_pending))

/*
 * We use macros to do YUV -> RGB conversion because this is
 * very important for speed and totally unimportant for size.
 *
 * YUV -> RGB Conversion
 * ---------------------
 *
 * B = 1.164*(Y-16)                 + 2.018*(V-128)
 * G = 1.164*(Y-16) - 0.813*(U-128) - 0.391*(V-128)
 * R = 1.164*(Y-16) + 1.596*(U-128)
 *
 * If you fancy integer arithmetics (as you should), hear this:
 *
 * 65536*B = 76284*(Y-16)                 + 132252*(V-128)
 * 65536*G = 76284*(Y-16) -  53281*(U-128) -  25625*(V-128)
 * 65536*R = 76284*(Y-16) + 104595*(U-128)
 *
 * Make sure the output values are within [0..255] range.
 */
#define LIMIT_RGB(x) (((x) < 0) ? 0 : (((x) > 255) ? 255 : (x)))
#define YUV_TO_RGB_BY_THE_BOOK(my,mu,mv,mr,mg,mb) { \
    int mm_y, mm_yc, mm_u, mm_v, mm_r, mm_g, mm_b; \
    mm_y = (my) - 16;  \
    mm_u = (mu) - 128; \
    mm_v = (mv) - 128; \
    mm_yc= mm_y * 76284; \
    mm_b = (mm_yc               + 132252*mm_v   ) >> 16; \
    mm_g = (mm_yc -  53281*mm_u -  25625*mm_v   ) >> 16; \
    mm_r = (mm_yc + 104595*mm_u                 ) >> 16; \
    mb = LIMIT_RGB(mm_b); \
    mg = LIMIT_RGB(mm_g); \
    mr = LIMIT_RGB(mm_r); \
}

#define RING_QUEUE_SIZE         (128*1024)      /* Must be a power of 2 */
#define RING_QUEUE_ADVANCE_INDEX(rq,ind,n) (rq)->ind = ((rq)->ind + (n)) & ((rq)->length-1)
#define RING_QUEUE_DEQUEUE_BYTES(rq,n) RING_QUEUE_ADVANCE_INDEX(rq,ri,n)
#define RING_QUEUE_PEEK(rq,ofs) ((rq)->queue[((ofs) + (rq)->ri) & ((rq)->length-1)])

struct RingQueue {
        unsigned char *queue;   /* Data from the Isoc data pump */
        int length;             /* How many bytes allocated for the queue */
        int wi;                 /* That's where we write */
        int ri;                 /* Read from here until you hit write index */
        wait_queue_head_t wqh;  /* Processes waiting */
};

enum ScanState {
        ScanState_Scanning,     /* Scanning for header */
        ScanState_Lines         /* Parsing lines */
};

/* Completion states of the data parser */
enum ParseState {
        scan_Continue,          /* Just parse next item */
        scan_NextFrame,         /* Frame done, send it to V4L */
        scan_Out,               /* Not enough data for frame */
        scan_EndParse           /* End parsing */
};

enum FrameState {
        FrameState_Unused,      /* Unused (no MCAPTURE) */
        FrameState_Ready,       /* Ready to start grabbing */
        FrameState_Grabbing,    /* In the process of being grabbed into */
        FrameState_Done,        /* Finished grabbing, but not been synced yet */
        FrameState_Done_Hold,   /* Are syncing or reading */
        FrameState_Error,       /* Something bad happened while processing */
};

/*
 * Some frames may contain only even or odd lines. This type
 * specifies what type of deinterlacing is required.
 */
enum Deinterlace {
        Deinterlace_None=0,
        Deinterlace_FillOddLines,
        Deinterlace_FillEvenLines
};

#define USBVIDEO_NUMFRAMES      2       /* How many frames we work with */
#define USBVIDEO_NUMSBUF        2       /* How many URBs linked in a ring */

/* This structure represents one Isoc request - URB and buffer */
struct usbvideo_sbuf {
        char *data;
        struct urb *urb;
};

struct usbvideo_frame {
        char *data;             /* Frame buffer */
        unsigned long header;   /* Significant bits from the header */

        videosize_t canvas;     /* The canvas (max. image) allocated */
        videosize_t request;    /* That's what the application asked for */
        unsigned short palette; /* The desired format */

        enum FrameState frameState;/* State of grabbing */
        enum ScanState scanstate;       /* State of scanning */
        enum Deinterlace deinterlace;
        int flags;              /* USBVIDEO_FRAME_FLAG_xxx bit flags */

        int curline;            /* Line of frame we're working on */

        long seqRead_Length;    /* Raw data length of frame */
        long seqRead_Index;     /* Amount of data that has been already read */

        void *user;             /* Additional data that user may need */
};

/* Statistics that can be overlaid on screen */
struct usbvideo_statistics {
        unsigned long frame_num;        /* Sequential number of the frame */
        unsigned long urb_count;        /* How many URBs we received so far */
        unsigned long urb_length;       /* Length of last URB */
        unsigned long data_count;       /* How many bytes we received */
        unsigned long header_count;     /* How many frame headers we found */
        unsigned long iso_skip_count;   /* How many empty ISO packets received */
        unsigned long iso_err_count;    /* How many bad ISO packets received */
};

struct usbvideo;

struct uvd {
        struct video_device vdev;       /* Must be the first field! */
        struct usb_device *dev;
        struct usbvideo *handle;        /* Points back to the struct usbvideo */
        void *user_data;                /* Camera-dependent data */
        int user_size;                  /* Size of that camera-dependent data */
        int debug;                      /* Debug level for usbvideo */
        unsigned char iface;            /* Video interface number */
        unsigned char video_endp;
        unsigned char ifaceAltActive;
        unsigned char ifaceAltInactive; /* Alt settings */
        unsigned long flags;            /* FLAGS_USBVIDEO_xxx */
        unsigned long paletteBits;      /* Which palettes we accept? */
        unsigned short defaultPalette;  /* What palette to use for read() */
        struct mutex lock;
        int user;               /* user count for exclusive use */

        videosize_t videosize;  /* Current setting */
        videosize_t canvas;     /* This is the width,height of the V4L canvas */
        int max_frame_size;     /* Bytes in one video frame */

        int uvd_used;           /* Is this structure in use? */
        int streaming;          /* Are we streaming Isochronous? */
        int grabbing;           /* Are we grabbing? */
        int settingsAdjusted;   /* Have we adjusted contrast etc.? */
        int last_error;         /* What calamity struck us? */

        char *fbuf;             /* Videodev buffer area */
        int fbuf_size;          /* Videodev buffer size */

        int curframe;
        int iso_packet_len;     /* Videomode-dependent, saves bus bandwidth */

        struct RingQueue dp;    /* Isoc data pump */
        struct usbvideo_frame frame[USBVIDEO_NUMFRAMES];
        struct usbvideo_sbuf sbuf[USBVIDEO_NUMSBUF];

        volatile int remove_pending;    /* If set then about to exit */

        struct video_picture vpic, vpic_old;    /* Picture settings */
        struct video_capability vcap;           /* Video capabilities */
        struct video_channel vchan;     /* May be used for tuner support */
        struct usbvideo_statistics stats;
        char videoName[32];             /* Holds name like "video7" */
};

/*
 * usbvideo callbacks (virtual methods). They are set when usbvideo
 * services are registered. All of these default to NULL, except those
 * that default to usbvideo-provided methods.
 */
struct usbvideo_cb {
        int (*probe)(struct usb_interface *, const struct usb_device_id *);
        void (*userFree)(struct uvd *);
        void (*disconnect)(struct usb_interface *);
        int (*setupOnOpen)(struct uvd *);
        void (*videoStart)(struct uvd *);
        void (*videoStop)(struct uvd *);
        void (*processData)(struct uvd *, struct usbvideo_frame *);
        void (*postProcess)(struct uvd *, struct usbvideo_frame *);
        void (*adjustPicture)(struct uvd *);
        int (*getFPS)(struct uvd *);
        int (*overlayHook)(struct uvd *, struct usbvideo_frame *);
        int (*getFrame)(struct uvd *, int);
        int (*startDataPump)(struct uvd *uvd);
        void (*stopDataPump)(struct uvd *uvd);
        int (*setVideoMode)(struct uvd *uvd, struct video_window *vw);
};

struct usbvideo {
        int num_cameras;                /* As allocated */
        struct usb_driver usbdrv;       /* Interface to the USB stack */
        char drvName[80];               /* Driver name */
        struct mutex lock;              /* Mutex protecting camera structures */
        struct usbvideo_cb cb;          /* Table of callbacks (virtual methods) */
        struct video_device vdt;        /* Video device template */
        struct uvd *cam;                        /* Array of camera structures */
        struct module *md_module;       /* Minidriver module */
};


/*
 * This macro retrieves callback address from the struct uvd object.
 * No validity checks are done here, so be sure to check the
 * callback beforehand with VALID_CALLBACK.
 */
#define GET_CALLBACK(uvd,cbName) ((uvd)->handle->cb.cbName)

/*
 * This macro returns either callback pointer or NULL. This is safe
 * macro, meaning that most of components of data structures involved
 * may be NULL - this only results in NULL being returned. You may
 * wish to use this macro to make sure that the callback is callable.
 * However keep in mind that those checks take time.
 */
#define VALID_CALLBACK(uvd,cbName) ((((uvd) != NULL) && \
                ((uvd)->handle != NULL)) ? GET_CALLBACK(uvd,cbName) : NULL)

int  RingQueue_Dequeue(struct RingQueue *rq, unsigned char *dst, int len);
int  RingQueue_Enqueue(struct RingQueue *rq, const unsigned char *cdata, int n);
void RingQueue_WakeUpInterruptible(struct RingQueue *rq);
void RingQueue_Flush(struct RingQueue *rq);

static inline int RingQueue_GetLength(const struct RingQueue *rq)
{
        return (rq->wi - rq->ri + rq->length) & (rq->length-1);
}

static inline int RingQueue_GetFreeSpace(const struct RingQueue *rq)
{
        return rq->length - RingQueue_GetLength(rq);
}

void usbvideo_DrawLine(
        struct usbvideo_frame *frame,
        int x1, int y1,
        int x2, int y2,
        unsigned char cr, unsigned char cg, unsigned char cb);
void usbvideo_HexDump(const unsigned char *data, int len);
void usbvideo_SayAndWait(const char *what);
void usbvideo_TestPattern(struct uvd *uvd, int fullframe, int pmode);

/* Memory allocation routines */
unsigned long usbvideo_kvirt_to_pa(unsigned long adr);

int usbvideo_register(
        struct usbvideo **pCams,
        const int num_cams,
        const int num_extra,
        const char *driverName,
        const struct usbvideo_cb *cbTable,
        struct module *md,
        const struct usb_device_id *id_table);
struct uvd *usbvideo_AllocateDevice(struct usbvideo *cams);
int usbvideo_RegisterVideoDevice(struct uvd *uvd);
void usbvideo_Deregister(struct usbvideo **uvt);

int usbvideo_v4l_initialize(struct video_device *dev);

void usbvideo_DeinterlaceFrame(struct uvd *uvd, struct usbvideo_frame *frame);

/*
 * This code performs bounds checking - use it when working with
 * new formats, or else you may get oopses all over the place.
 * If pixel falls out of bounds then it gets shoved back (as close
 * to place of offence as possible) and is painted bright red.
 *
 * There are two important concepts: frame width, height and
 * V4L canvas width, height. The former is the area requested by
 * the application -for this very frame-. The latter is the largest
 * possible frame that we can serve (we advertise that via V4L ioctl).
 * The frame data is expected to be formatted as lines of length
 * VIDEOSIZE_X(fr->request), total VIDEOSIZE_Y(frame->request) lines.
 */
static inline void RGB24_PUTPIXEL(
        struct usbvideo_frame *fr,
        int ix, int iy,
        unsigned char vr,
        unsigned char vg,
        unsigned char vb)
{
        register unsigned char *pf;
        int limiter = 0, mx, my;
        mx = ix;
        my = iy;
        if (mx < 0) {
                mx=0;
                limiter++;
        } else if (mx >= VIDEOSIZE_X((fr)->request)) {
                mx= VIDEOSIZE_X((fr)->request) - 1;
                limiter++;
        }
        if (my < 0) {
                my = 0;
                limiter++;
        } else if (my >= VIDEOSIZE_Y((fr)->request)) {
                my = VIDEOSIZE_Y((fr)->request) - 1;
                limiter++;
        }
        pf = (fr)->data + V4L_BYTES_PER_PIXEL*((iy)*VIDEOSIZE_X((fr)->request) + (ix));
        if (limiter) {
                *pf++ = 0;
                *pf++ = 0;
                *pf++ = 0xFF;
        } else {
                *pf++ = (vb);
                *pf++ = (vg);
                *pf++ = (vr);
        }
}

#endif /* usbvideo_h */