ivtv-vbi.c

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/*
    Vertical Blank Interval support functions
    Copyright (C) 2004-2007  Hans Verkuil <[email protected]>

    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.

    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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "ivtv-driver.h"
#include "ivtv-i2c.h"
#include "ivtv-ioctl.h"
#include "ivtv-queue.h"
#include "ivtv-cards.h"
#include "ivtv-vbi.h"

static void ivtv_set_vps(struct ivtv *itv, int enabled)
{
    struct v4l2_sliced_vbi_data data;

    if (!(itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT))
        return;
    data.id = V4L2_SLICED_VPS;
    data.field = 0;
    data.line = enabled ? 16 : 0;
    data.data[2] = itv->vbi.vps_payload.data[0];
    data.data[8] = itv->vbi.vps_payload.data[1];
    data.data[9] = itv->vbi.vps_payload.data[2];
    data.data[10] = itv->vbi.vps_payload.data[3];
    data.data[11] = itv->vbi.vps_payload.data[4];
    ivtv_call_hw(itv, IVTV_HW_SAA7127, vbi, s_vbi_data, &data);
}

static void ivtv_set_cc(struct ivtv *itv, int mode, const struct vbi_cc *cc)
{
    struct v4l2_sliced_vbi_data data;

    if (!(itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT))
        return;
    data.id = V4L2_SLICED_CAPTION_525;
    data.field = 0;
    data.line = (mode & 1) ? 21 : 0;
    data.data[0] = cc->odd[0];
    data.data[1] = cc->odd[1];
    ivtv_call_hw(itv, IVTV_HW_SAA7127, vbi, s_vbi_data, &data);
    data.field = 1;
    data.line = (mode & 2) ? 21 : 0;
    data.data[0] = cc->even[0];
    data.data[1] = cc->even[1];
    ivtv_call_hw(itv, IVTV_HW_SAA7127, vbi, s_vbi_data, &data);
}

static void ivtv_set_wss(struct ivtv *itv, int enabled, int mode)
{
    struct v4l2_sliced_vbi_data data;

    if (!(itv->v4l2_cap & V4L2_CAP_VIDEO_OUTPUT))
        return;
    /* When using a 50 Hz system, always turn on the
       wide screen signal with 4x3 ratio as the default.
       Turning this signal on and off can confuse certain
       TVs. As far as I can tell there is no reason not to
       transmit this signal. */
    if ((itv->std_out & V4L2_STD_625_50) && !enabled) {
        enabled = 1;
        mode = 0x08;  /* 4x3 full format */
    }
    data.id = V4L2_SLICED_WSS_625;
    data.field = 0;
    data.line = enabled ? 23 : 0;
    data.data[0] = mode & 0xff;
    data.data[1] = (mode >> 8) & 0xff;
    ivtv_call_hw(itv, IVTV_HW_SAA7127, vbi, s_vbi_data, &data);
}

static int odd_parity(u8 c)
{
    c ^= (c >> 4);
    c ^= (c >> 2);
    c ^= (c >> 1);

    return c & 1;
}

static void ivtv_write_vbi_line(struct ivtv *itv,
                const struct v4l2_sliced_vbi_data *d,
                struct vbi_cc *cc, int *found_cc)
{
    struct vbi_info *vi = &itv->vbi;

    if (d->id == V4L2_SLICED_CAPTION_525 && d->line == 21) {
        if (d->field) {
            cc->even[0] = d->data[0];
            cc->even[1] = d->data[1];
        } else {
            cc->odd[0] = d->data[0];
            cc->odd[1] = d->data[1];
        }
        *found_cc = 1;
    } else if (d->id == V4L2_SLICED_VPS && d->line == 16 && d->field == 0) {
        struct vbi_vps vps;

        vps.data[0] = d->data[2];
        vps.data[1] = d->data[8];
        vps.data[2] = d->data[9];
        vps.data[3] = d->data[10];
        vps.data[4] = d->data[11];
        if (memcmp(&vps, &vi->vps_payload, sizeof(vps))) {
            vi->vps_payload = vps;
            set_bit(IVTV_F_I_UPDATE_VPS, &itv->i_flags);
        }
    } else if (d->id == V4L2_SLICED_WSS_625 &&
           d->line == 23 && d->field == 0) {
        int wss = d->data[0] | d->data[1] << 8;

        if (vi->wss_payload != wss) {
            vi->wss_payload = wss;
            set_bit(IVTV_F_I_UPDATE_WSS, &itv->i_flags);
        }
    }
}

static void ivtv_write_vbi_cc_lines(struct ivtv *itv, const struct vbi_cc *cc)
{
    struct vbi_info *vi = &itv->vbi;

    if (vi->cc_payload_idx < ARRAY_SIZE(vi->cc_payload)) {
        memcpy(&vi->cc_payload[vi->cc_payload_idx], cc,
               sizeof(struct vbi_cc));
        vi->cc_payload_idx++;
        set_bit(IVTV_F_I_UPDATE_CC, &itv->i_flags);
    }
}

static void ivtv_write_vbi(struct ivtv *itv,
               const struct v4l2_sliced_vbi_data *sliced,
               size_t cnt)
{
    struct vbi_cc cc = { .odd = { 0x80, 0x80 }, .even = { 0x80, 0x80 } };
    int found_cc = 0;
    size_t i;

    for (i = 0; i < cnt; i++)
        ivtv_write_vbi_line(itv, sliced + i, &cc, &found_cc);

    if (found_cc)
        ivtv_write_vbi_cc_lines(itv, &cc);
}

ssize_t
ivtv_write_vbi_from_user(struct ivtv *itv,
             const struct v4l2_sliced_vbi_data __user *sliced,
             size_t cnt)
{
    struct vbi_cc cc = { .odd = { 0x80, 0x80 }, .even = { 0x80, 0x80 } };
    int found_cc = 0;
    size_t i;
    struct v4l2_sliced_vbi_data d;
    ssize_t ret = cnt * sizeof(struct v4l2_sliced_vbi_data);

    for (i = 0; i < cnt; i++) {
        if (copy_from_user(&d, sliced + i,
                   sizeof(struct v4l2_sliced_vbi_data))) {
            ret = -EFAULT;
            break;
        }
        ivtv_write_vbi_line(itv, &d, &cc, &found_cc);
    }

    if (found_cc)
        ivtv_write_vbi_cc_lines(itv, &cc);

    return ret;
}

static void copy_vbi_data(struct ivtv *itv, int lines, u32 pts_stamp)
{
    int line = 0;
    int i;
    u32 linemask[2] = { 0, 0 };
    unsigned short size;
    static const u8 mpeg_hdr_data[] = {
        0x00, 0x00, 0x01, 0xba, 0x44, 0x00, 0x0c, 0x66,
        0x24, 0x01, 0x01, 0xd1, 0xd3, 0xfa, 0xff, 0xff,
        0x00, 0x00, 0x01, 0xbd, 0x00, 0x1a, 0x84, 0x80,
        0x07, 0x21, 0x00, 0x5d, 0x63, 0xa7, 0xff, 0xff
    };
    const int sd = sizeof(mpeg_hdr_data);   /* start of vbi data */
    int idx = itv->vbi.frame % IVTV_VBI_FRAMES;
    u8 *dst = &itv->vbi.sliced_mpeg_data[idx][0];

    for (i = 0; i < lines; i++) {
        int f, l;

        if (itv->vbi.sliced_data[i].id == 0)
            continue;

        l = itv->vbi.sliced_data[i].line - 6;
        f = itv->vbi.sliced_data[i].field;
        if (f)
            l += 18;
        if (l < 32)
            linemask[0] |= (1 << l);
        else
            linemask[1] |= (1 << (l - 32));
        dst[sd + 12 + line * 43] =
            ivtv_service2vbi(itv->vbi.sliced_data[i].id);
        memcpy(dst + sd + 12 + line * 43 + 1, itv->vbi.sliced_data[i].data, 42);
        line++;
    }
    memcpy(dst, mpeg_hdr_data, sizeof(mpeg_hdr_data));
    if (line == 36) {
        /* All lines are used, so there is no space for the linemask
           (the max size of the VBI data is 36 * 43 + 4 bytes).
           So in this case we use the magic number 'ITV0'. */
        memcpy(dst + sd, "ITV0", 4);
        memcpy(dst + sd + 4, dst + sd + 12, line * 43);
        size = 4 + ((43 * line + 3) & ~3);
    } else {
        memcpy(dst + sd, "itv0", 4);
        cpu_to_le32s(&linemask[0]);
        cpu_to_le32s(&linemask[1]);
        memcpy(dst + sd + 4, &linemask[0], 8);
        size = 12 + ((43 * line + 3) & ~3);
    }
    dst[4+16] = (size + 10) >> 8;
    dst[5+16] = (size + 10) & 0xff;
    dst[9+16] = 0x21 | ((pts_stamp >> 29) & 0x6);
    dst[10+16] = (pts_stamp >> 22) & 0xff;
    dst[11+16] = 1 | ((pts_stamp >> 14) & 0xff);
    dst[12+16] = (pts_stamp >> 7) & 0xff;
    dst[13+16] = 1 | ((pts_stamp & 0x7f) << 1);
    itv->vbi.sliced_mpeg_size[idx] = sd + size;
}

static int ivtv_convert_ivtv_vbi(struct ivtv *itv, u8 *p)
{
    u32 linemask[2];
    int i, l, id2;
    int line = 0;

    if (!memcmp(p, "itv0", 4)) {
        memcpy(linemask, p + 4, 8);
        p += 12;
    } else if (!memcmp(p, "ITV0", 4)) {
        linemask[0] = 0xffffffff;
        linemask[1] = 0xf;
        p += 4;
    } else {
        /* unknown VBI data, convert to empty VBI frame */
        linemask[0] = linemask[1] = 0;
    }
    for (i = 0; i < 36; i++) {
        int err = 0;

        if (i < 32 && !(linemask[0] & (1 << i)))
            continue;
        if (i >= 32 && !(linemask[1] & (1 << (i - 32))))
            continue;
        id2 = *p & 0xf;
        switch (id2) {
        case IVTV_SLICED_TYPE_TELETEXT_B:
            id2 = V4L2_SLICED_TELETEXT_B;
            break;
        case IVTV_SLICED_TYPE_CAPTION_525:
            id2 = V4L2_SLICED_CAPTION_525;
            err = !odd_parity(p[1]) || !odd_parity(p[2]);
            break;
        case IVTV_SLICED_TYPE_VPS:
            id2 = V4L2_SLICED_VPS;
            break;
        case IVTV_SLICED_TYPE_WSS_625:
            id2 = V4L2_SLICED_WSS_625;
            break;
        default:
            id2 = 0;
            break;
        }
        if (err == 0) {
            l = (i < 18) ? i + 6 : i - 18 + 6;
            itv->vbi.sliced_dec_data[line].line = l;
            itv->vbi.sliced_dec_data[line].field = i >= 18;
            itv->vbi.sliced_dec_data[line].id = id2;
            memcpy(itv->vbi.sliced_dec_data[line].data, p + 1, 42);
            line++;
        }
        p += 43;
    }
    while (line < 36) {
        itv->vbi.sliced_dec_data[line].id = 0;
        itv->vbi.sliced_dec_data[line].line = 0;
        itv->vbi.sliced_dec_data[line].field = 0;
        line++;
    }
    return line * sizeof(itv->vbi.sliced_dec_data[0]);
}

/* Compress raw VBI format, removes leading SAV codes and surplus space after the
   field.
   Returns new compressed size. */
static u32 compress_raw_buf(struct ivtv *itv, u8 *buf, u32 size)
{
    u32 line_size = itv->vbi.raw_decoder_line_size;
    u32 lines = itv->vbi.count;
    u8 sav1 = itv->vbi.raw_decoder_sav_odd_field;
    u8 sav2 = itv->vbi.raw_decoder_sav_even_field;
    u8 *q = buf;
    u8 *p;
    int i;

    for (i = 0; i < lines; i++) {
        p = buf + i * line_size;

        /* Look for SAV code */
        if (p[0] != 0xff || p[1] || p[2] || (p[3] != sav1 && p[3] != sav2)) {
            break;
        }
        memcpy(q, p + 4, line_size - 4);
        q += line_size - 4;
    }
    return lines * (line_size - 4);
}


/* Compressed VBI format, all found sliced blocks put next to one another
   Returns new compressed size */
static u32 compress_sliced_buf(struct ivtv *itv, u32 line, u8 *buf, u32 size, u8 sav)
{
    u32 line_size = itv->vbi.sliced_decoder_line_size;
    struct v4l2_decode_vbi_line vbi;
    int i;
    unsigned lines = 0;

    /* find the first valid line */
    for (i = 0; i < size; i++, buf++) {
        if (buf[0] == 0xff && !buf[1] && !buf[2] && buf[3] == sav)
            break;
    }

    size -= i;
    if (size < line_size) {
        return line;
    }
    for (i = 0; i < size / line_size; i++) {
        u8 *p = buf + i * line_size;

        /* Look for SAV code  */
        if (p[0] != 0xff || p[1] || p[2] || p[3] != sav) {
            continue;
        }
        vbi.p = p + 4;
        v4l2_subdev_call(itv->sd_video, vbi, decode_vbi_line, &vbi);
        if (vbi.type && !(lines & (1 << vbi.line))) {
            lines |= 1 << vbi.line;
            itv->vbi.sliced_data[line].id = vbi.type;
            itv->vbi.sliced_data[line].field = vbi.is_second_field;
            itv->vbi.sliced_data[line].line = vbi.line;
            memcpy(itv->vbi.sliced_data[line].data, vbi.p, 42);
            line++;
        }
    }
    return line;
}

void ivtv_process_vbi_data(struct ivtv *itv, struct ivtv_buffer *buf,
               u64 pts_stamp, int streamtype)
{
    u8 *p = (u8 *) buf->buf;
    u32 size = buf->bytesused;
    int y;

    /* Raw VBI data */
    if (streamtype == IVTV_ENC_STREAM_TYPE_VBI && ivtv_raw_vbi(itv)) {
        u8 type;

        ivtv_buf_swap(buf);

        type = p[3];

        size = buf->bytesused = compress_raw_buf(itv, p, size);

        /* second field of the frame? */
        if (type == itv->vbi.raw_decoder_sav_even_field) {
            /* Dirty hack needed for backwards
               compatibility of old VBI software. */
            p += size - 4;
            memcpy(p, &itv->vbi.frame, 4);
            itv->vbi.frame++;
        }
        return;
    }

    /* Sliced VBI data with data insertion */
    if (streamtype == IVTV_ENC_STREAM_TYPE_VBI) {
        int lines;

        ivtv_buf_swap(buf);

        /* first field */
        lines = compress_sliced_buf(itv, 0, p, size / 2,
            itv->vbi.sliced_decoder_sav_odd_field);
        /* second field */
        /* experimentation shows that the second half does not always begin
           at the exact address. So start a bit earlier (hence 32). */
        lines = compress_sliced_buf(itv, lines, p + size / 2 - 32, size / 2 + 32,
            itv->vbi.sliced_decoder_sav_even_field);
        /* always return at least one empty line */
        if (lines == 0) {
            itv->vbi.sliced_data[0].id = 0;
            itv->vbi.sliced_data[0].line = 0;
            itv->vbi.sliced_data[0].field = 0;
            lines = 1;
        }
        buf->bytesused = size = lines * sizeof(itv->vbi.sliced_data[0]);
        memcpy(p, &itv->vbi.sliced_data[0], size);

        if (itv->vbi.insert_mpeg) {
            copy_vbi_data(itv, lines, pts_stamp);
        }
        itv->vbi.frame++;
        return;
    }

    /* Sliced VBI re-inserted from an MPEG stream */
    if (streamtype == IVTV_DEC_STREAM_TYPE_VBI) {
        /* If the size is not 4-byte aligned, then the starting address
           for the swapping is also shifted. After swapping the data the
           real start address of the VBI data is exactly 4 bytes after the
           original start. It's a bit fiddly but it works like a charm.
           Non-4-byte alignment happens when an lseek is done on the input
           mpeg file to a non-4-byte aligned position. So on arrival here
           the VBI data is also non-4-byte aligned. */
        int offset = size & 3;
        int cnt;

        if (offset) {
            p += 4 - offset;
        }
        /* Swap Buffer */
        for (y = 0; y < size; y += 4) {
               swab32s((u32 *)(p + y));
        }

        cnt = ivtv_convert_ivtv_vbi(itv, p + offset);
        memcpy(buf->buf, itv->vbi.sliced_dec_data, cnt);
        buf->bytesused = cnt;

        ivtv_write_vbi(itv, itv->vbi.sliced_dec_data,
                   cnt / sizeof(itv->vbi.sliced_dec_data[0]));
        return;
    }
}

void ivtv_disable_cc(struct ivtv *itv)
{
    struct vbi_cc cc = { .odd = { 0x80, 0x80 }, .even = { 0x80, 0x80 } };

    clear_bit(IVTV_F_I_UPDATE_CC, &itv->i_flags);
    ivtv_set_cc(itv, 0, &cc);
    itv->vbi.cc_payload_idx = 0;
}


void ivtv_vbi_work_handler(struct ivtv *itv)
{
    struct vbi_info *vi = &itv->vbi;
    struct v4l2_sliced_vbi_data data;
    struct vbi_cc cc = { .odd = { 0x80, 0x80 }, .even = { 0x80, 0x80 } };

    /* Lock */
    if (itv->output_mode == OUT_PASSTHROUGH) {
        if (itv->is_50hz) {
            data.id = V4L2_SLICED_WSS_625;
            data.field = 0;

            if (v4l2_subdev_call(itv->sd_video, vbi, g_vbi_data, &data) == 0) {
                ivtv_set_wss(itv, 1, data.data[0] & 0xf);
                vi->wss_missing_cnt = 0;
            } else if (vi->wss_missing_cnt == 4) {
                ivtv_set_wss(itv, 1, 0x8);  /* 4x3 full format */
            } else {
                vi->wss_missing_cnt++;
            }
        }
        else {
            int mode = 0;

            data.id = V4L2_SLICED_CAPTION_525;
            data.field = 0;
            if (v4l2_subdev_call(itv->sd_video, vbi, g_vbi_data, &data) == 0) {
                mode |= 1;
                cc.odd[0] = data.data[0];
                cc.odd[1] = data.data[1];
            }
            data.field = 1;
            if (v4l2_subdev_call(itv->sd_video, vbi, g_vbi_data, &data) == 0) {
                mode |= 2;
                cc.even[0] = data.data[0];
                cc.even[1] = data.data[1];
            }
            if (mode) {
                vi->cc_missing_cnt = 0;
                ivtv_set_cc(itv, mode, &cc);
            } else if (vi->cc_missing_cnt == 4) {
                ivtv_set_cc(itv, 0, &cc);
            } else {
                vi->cc_missing_cnt++;
            }
        }
        return;
    }

    if (test_and_clear_bit(IVTV_F_I_UPDATE_WSS, &itv->i_flags)) {
        ivtv_set_wss(itv, 1, vi->wss_payload & 0xf);
    }

    if (test_bit(IVTV_F_I_UPDATE_CC, &itv->i_flags)) {
        if (vi->cc_payload_idx == 0) {
            clear_bit(IVTV_F_I_UPDATE_CC, &itv->i_flags);
            ivtv_set_cc(itv, 3, &cc);
        }
        while (vi->cc_payload_idx) {
            cc = vi->cc_payload[0];

            memcpy(vi->cc_payload, vi->cc_payload + 1,
                    sizeof(vi->cc_payload) - sizeof(vi->cc_payload[0]));
            vi->cc_payload_idx--;
            if (vi->cc_payload_idx && cc.odd[0] == 0x80 && cc.odd[1] == 0x80)
                continue;

            ivtv_set_cc(itv, 3, &cc);
            break;
        }
    }

    if (test_and_clear_bit(IVTV_F_I_UPDATE_VPS, &itv->i_flags)) {
        ivtv_set_vps(itv, 1);
    }
}