LXR linux/drivers/media/pci/cx18/cx18-vbi.c

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 *  cx18 Vertical Blank Interval support functions
   4 *
   5 *  Derived from ivtv-vbi.c
   6 *
   7 *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
   8 */
   9
  10#include "cx18-driver.h"
  11#include "cx18-vbi.h"
  12#include "cx18-ioctl.h"
  13#include "cx18-queue.h"
  14
  15/*
  16 * Raster Reference/Protection (RP) bytes, used in Start/End Active
  17 * Video codes emitted from the digitzer in VIP 1.x mode, that flag the start
  18 * of VBI sample or VBI ancillary data regions in the digital ratser line.
  19 *
  20 * Task FieldEven VerticalBlank HorizontalBlank 0 0 0 0
  21 */
  22static const u8 raw_vbi_sav_rp[2] = { 0x20, 0x60 };    /* __V_, _FV_ */
  23static const u8 sliced_vbi_eav_rp[2] = { 0xb0, 0xf0 }; /* T_VH, TFVH */
  24
  25static void copy_vbi_data(struct cx18 *cx, int lines, u32 pts_stamp)
  26{
  27        int line = 0;
  28        int i;
  29        u32 linemask[2] = { 0, 0 };
  30        unsigned short size;
  31        static const u8 mpeg_hdr_data[] = {
  32                /* MPEG-2 Program Pack */
  33                0x00, 0x00, 0x01, 0xba,             /* Prog Pack start code */
  34                0x44, 0x00, 0x0c, 0x66, 0x24, 0x01, /* SCR, SCR Ext, markers */
  35                0x01, 0xd1, 0xd3,                   /* Mux Rate, markers */
  36                0xfa, 0xff, 0xff,                   /* Res, Suff cnt, Stuff */
  37                /* MPEG-2 Private Stream 1 PES Packet */
  38                0x00, 0x00, 0x01, 0xbd,             /* Priv Stream 1 start */
  39                0x00, 0x1a,                         /* length */
  40                0x84, 0x80, 0x07,                   /* flags, hdr data len */
  41                0x21, 0x00, 0x5d, 0x63, 0xa7,       /* PTS, markers */
  42                0xff, 0xff                          /* stuffing */
  43        };
  44        const int sd = sizeof(mpeg_hdr_data);   /* start of vbi data */
  45        int idx = cx->vbi.frame % CX18_VBI_FRAMES;
  46        u8 *dst = &cx->vbi.sliced_mpeg_data[idx][0];
  47
  48        for (i = 0; i < lines; i++) {
  49                struct v4l2_sliced_vbi_data *sdata = cx->vbi.sliced_data + i;
  50                int f, l;
  51
  52                if (sdata->id == 0)
  53                        continue;
  54
  55                l = sdata->line - 6;
  56                f = sdata->field;
  57                if (f)
  58                        l += 18;
  59                if (l < 32)
  60                        linemask[0] |= (1 << l);
  61                else
  62                        linemask[1] |= (1 << (l - 32));
  63                dst[sd + 12 + line * 43] = cx18_service2vbi(sdata->id);
  64                memcpy(dst + sd + 12 + line * 43 + 1, sdata->data, 42);
  65                line++;
  66        }
  67        memcpy(dst, mpeg_hdr_data, sizeof(mpeg_hdr_data));
  68        if (line == 36) {
  69                /* All lines are used, so there is no space for the linemask
  70                   (the max size of the VBI data is 36 * 43 + 4 bytes).
  71                   So in this case we use the magic number 'ITV0'. */
  72                memcpy(dst + sd, "ITV0", 4);
  73                memmove(dst + sd + 4, dst + sd + 12, line * 43);
  74                size = 4 + ((43 * line + 3) & ~3);
  75        } else {
  76                memcpy(dst + sd, "itv0", 4);
  77                cpu_to_le32s(&linemask[0]);
  78                cpu_to_le32s(&linemask[1]);
  79                memcpy(dst + sd + 4, &linemask[0], 8);
  80                size = 12 + ((43 * line + 3) & ~3);
  81        }
  82        dst[4+16] = (size + 10) >> 8;
  83        dst[5+16] = (size + 10) & 0xff;
  84        dst[9+16] = 0x21 | ((pts_stamp >> 29) & 0x6);
  85        dst[10+16] = (pts_stamp >> 22) & 0xff;
  86        dst[11+16] = 1 | ((pts_stamp >> 14) & 0xff);
  87        dst[12+16] = (pts_stamp >> 7) & 0xff;
  88        dst[13+16] = 1 | ((pts_stamp & 0x7f) << 1);
  89        cx->vbi.sliced_mpeg_size[idx] = sd + size;
  90}
  91
  92/* Compress raw VBI format, removes leading SAV codes and surplus space
  93   after the frame.  Returns new compressed size. */
  94/* FIXME - this function ignores the input size. */
  95static u32 compress_raw_buf(struct cx18 *cx, u8 *buf, u32 size, u32 hdr_size)
  96{
  97        u32 line_size = VBI_ACTIVE_SAMPLES;
  98        u32 lines = cx->vbi.count * 2;
  99        u8 *q = buf;
 100        u8 *p;
 101        int i;
 102
 103        /* Skip the header */
 104        buf += hdr_size;
 105
 106        for (i = 0; i < lines; i++) {
 107                p = buf + i * line_size;
 108
 109                /* Look for SAV code */
 110                if (p[0] != 0xff || p[1] || p[2] ||
 111                    (p[3] != raw_vbi_sav_rp[0] &&
 112                     p[3] != raw_vbi_sav_rp[1]))
 113                        break;
 114                if (i == lines - 1) {
 115                        /* last line is hdr_size bytes short - extrapolate it */
 116                        memcpy(q, p + 4, line_size - 4 - hdr_size);
 117                        q += line_size - 4 - hdr_size;
 118                        p += line_size - hdr_size - 1;
 119                        memset(q, (int) *p, hdr_size);
 120                } else {
 121                        memcpy(q, p + 4, line_size - 4);
 122                        q += line_size - 4;
 123                }
 124        }
 125        return lines * (line_size - 4);
 126}
 127
 128static u32 compress_sliced_buf(struct cx18 *cx, u8 *buf, u32 size,
 129                               const u32 hdr_size)
 130{
 131        struct v4l2_decode_vbi_line vbi;
 132        int i;
 133        u32 line = 0;
 134        u32 line_size = cx->is_60hz ? VBI_HBLANK_SAMPLES_60HZ
 135                                    : VBI_HBLANK_SAMPLES_50HZ;
 136
 137        /* find the first valid line */
 138        for (i = hdr_size, buf += hdr_size; i < size; i++, buf++) {
 139                if (buf[0] == 0xff && !buf[1] && !buf[2] &&
 140                    (buf[3] == sliced_vbi_eav_rp[0] ||
 141                     buf[3] == sliced_vbi_eav_rp[1]))
 142                        break;
 143        }
 144
 145        /*
 146         * The last line is short by hdr_size bytes, but for the remaining
 147         * checks against size, we pretend that it is not, by counting the
 148         * header bytes we knowingly skipped
 149         */
 150        size -= (i - hdr_size);
 151        if (size < line_size)
 152                return line;
 153
 154        for (i = 0; i < size / line_size; i++) {
 155                u8 *p = buf + i * line_size;
 156
 157                /* Look for EAV code  */
 158                if (p[0] != 0xff || p[1] || p[2] ||
 159                    (p[3] != sliced_vbi_eav_rp[0] &&
 160                     p[3] != sliced_vbi_eav_rp[1]))
 161                        continue;
 162                vbi.p = p + 4;
 163                v4l2_subdev_call(cx->sd_av, vbi, decode_vbi_line, &vbi);
 164                if (vbi.type) {
 165                        cx->vbi.sliced_data[line].id = vbi.type;
 166                        cx->vbi.sliced_data[line].field = vbi.is_second_field;
 167                        cx->vbi.sliced_data[line].line = vbi.line;
 168                        memcpy(cx->vbi.sliced_data[line].data, vbi.p, 42);
 169                        line++;
 170                }
 171        }
 172        return line;
 173}
 174
 175static void _cx18_process_vbi_data(struct cx18 *cx, struct cx18_buffer *buf)
 176{
 177        /*
 178         * The CX23418 provides a 12 byte header in its raw VBI buffers to us:
 179         * 0x3fffffff [4 bytes of something] [4 byte presentation time stamp]
 180         */
 181        struct vbi_data_hdr {
 182                __be32 magic;
 183                __be32 unknown;
 184                __be32 pts;
 185        } *hdr = (struct vbi_data_hdr *) buf->buf;
 186
 187        u8 *p = (u8 *) buf->buf;
 188        u32 size = buf->bytesused;
 189        u32 pts;
 190        int lines;
 191
 192        /*
 193         * The CX23418 sends us data that is 32 bit little-endian swapped,
 194         * but we want the raw VBI bytes in the order they were in the raster
 195         * line.  This has a side effect of making the header big endian
 196         */
 197        cx18_buf_swap(buf);
 198
 199        /* Raw VBI data */
 200        if (cx18_raw_vbi(cx)) {
 201
 202                size = buf->bytesused =
 203                     compress_raw_buf(cx, p, size, sizeof(struct vbi_data_hdr));
 204
 205                /*
 206                 * Hack needed for compatibility with old VBI software.
 207                 * Write the frame # at the last 4 bytes of the frame
 208                 */
 209                p += size - 4;
 210                memcpy(p, &cx->vbi.frame, 4);
 211                cx->vbi.frame++;
 212                return;
 213        }
 214
 215        /* Sliced VBI data with data insertion */
 216
 217        pts = (be32_to_cpu(hdr->magic) == 0x3fffffff) ? be32_to_cpu(hdr->pts)
 218                                                      : 0;
 219
 220        lines = compress_sliced_buf(cx, p, size, sizeof(struct vbi_data_hdr));
 221
 222        /* always return at least one empty line */
 223        if (lines == 0) {
 224                cx->vbi.sliced_data[0].id = 0;
 225                cx->vbi.sliced_data[0].line = 0;
 226                cx->vbi.sliced_data[0].field = 0;
 227                lines = 1;
 228        }
 229        buf->bytesused = size = lines * sizeof(cx->vbi.sliced_data[0]);
 230        memcpy(p, &cx->vbi.sliced_data[0], size);
 231
 232        if (cx->vbi.insert_mpeg)
 233                copy_vbi_data(cx, lines, pts);
 234        cx->vbi.frame++;
 235}
 236
 237void cx18_process_vbi_data(struct cx18 *cx, struct cx18_mdl *mdl,
 238                           int streamtype)
 239{
 240        struct cx18_buffer *buf;
 241        u32 orig_used;
 242
 243        if (streamtype != CX18_ENC_STREAM_TYPE_VBI)
 244                return;
 245
 246        /*
 247         * Big assumption here:
 248         * Every buffer hooked to the MDL's buf_list is a complete VBI frame
 249         * that ends at the end of the buffer.
 250         *
 251         * To assume anything else would make the code in this file
 252         * more complex, or require extra memcpy()'s to make the
 253         * buffers satisfy the above assumption.  It's just simpler to set
 254         * up the encoder buffer transfers to make the assumption true.
 255         */
 256        list_for_each_entry(buf, &mdl->buf_list, list) {
 257                orig_used = buf->bytesused;
 258                if (orig_used == 0)
 259                        break;
 260                _cx18_process_vbi_data(cx, buf);
 261                mdl->bytesused -= (orig_used - buf->bytesused);
 262        }
 263}
 264