drivers/media/video/cx18/cx18-vbi.c

   1 /*
   2  *  cx18 Vertical Blank Interval support functions
   3  *
   4  *  Derived from ivtv-vbi.c
   5  *
   6  *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  21  *  02111-1307  USA
  22  */
  23
  24 #include "cx18-driver.h"
  25 #include "cx18-vbi.h"
  26 #include "cx18-ioctl.h"
  27 #include "cx18-queue.h"
  28
  29 /*
  30  * Raster Reference/Protection (RP) bytes, used in Start/End Active
  31  * Video codes emitted from the digitzer in VIP 1.x mode, that flag the start
  32  * of VBI sample or VBI ancilliary data regions in the digitial ratser line.
  33  *
  34  * Task FieldEven VerticalBlank HorizontalBlank 0 0 0 0
  35  */
  36 static const u8 raw_vbi_sav_rp[2] = { 0x20, 0x60 };    /* __V_, _FV_ */
  37 static const u8 sliced_vbi_eav_rp[2] = { 0xb0, 0xf0 }; /* T_VH, TFVH */
  38
  39 static void copy_vbi_data(struct cx18 *cx, int lines, u32 pts_stamp)
  40 {
  41         int line = 0;
  42         int i;
  43         u32 linemask[2] = { 0, 0 };
  44         unsigned short size;
  45         static const u8 mpeg_hdr_data[] = {
  46                 /* MPEG-2 Program Pack */
  47                 0x00, 0x00, 0x01, 0xba,             /* Prog Pack start code */
  48                 0x44, 0x00, 0x0c, 0x66, 0x24, 0x01, /* SCR, SCR Ext, markers */
  49                 0x01, 0xd1, 0xd3,                   /* Mux Rate, markers */
  50                 0xfa, 0xff, 0xff,                   /* Res, Suff cnt, Stuff */
  51                 /* MPEG-2 Private Stream 1 PES Packet */
  52                 0x00, 0x00, 0x01, 0xbd,             /* Priv Stream 1 start */
  53                 0x00, 0x1a,                         /* length */
  54                 0x84, 0x80, 0x07,                   /* flags, hdr data len */
  55                 0x21, 0x00, 0x5d, 0x63, 0xa7,       /* PTS, markers */
  56                 0xff, 0xff                          /* stuffing */
  57         };
  58         const int sd = sizeof(mpeg_hdr_data);   /* start of vbi data */
  59         int idx = cx->vbi.frame % CX18_VBI_FRAMES;
  60         u8 *dst = &cx->vbi.sliced_mpeg_data[idx][0];
  61
  62         for (i = 0; i < lines; i++) {
  63                 struct v4l2_sliced_vbi_data *sdata = cx->vbi.sliced_data + i;
  64                 int f, l;
  65
  66                 if (sdata->id == 0)
  67                         continue;
  68
  69                 l = sdata->line - 6;
  70                 f = sdata->field;
  71                 if (f)
  72                         l += 18;
  73                 if (l < 32)
  74                         linemask[0] |= (1 << l);
  75                 else
  76                         linemask[1] |= (1 << (l - 32));
  77                 dst[sd + 12 + line * 43] = cx18_service2vbi(sdata->id);
  78                 memcpy(dst + sd + 12 + line * 43 + 1, sdata->data, 42);
  79                 line++;
  80         }
  81         memcpy(dst, mpeg_hdr_data, sizeof(mpeg_hdr_data));
  82         if (line == 36) {
  83                 /* All lines are used, so there is no space for the linemask
  84                    (the max size of the VBI data is 36 * 43 + 4 bytes).
  85                    So in this case we use the magic number 'ITV0'. */
  86                 memcpy(dst + sd, "ITV0", 4);
  87                 memcpy(dst + sd + 4, dst + sd + 12, line * 43);
  88                 size = 4 + ((43 * line + 3) & ~3);
  89         } else {
  90                 memcpy(dst + sd, "itv0", 4);
  91                 cpu_to_le32s(&linemask[0]);
  92                 cpu_to_le32s(&linemask[1]);
  93                 memcpy(dst + sd + 4, &linemask[0], 8);
  94                 size = 12 + ((43 * line + 3) & ~3);
  95         }
  96         dst[4+16] = (size + 10) >> 8;
  97         dst[5+16] = (size + 10) & 0xff;
  98         dst[9+16] = 0x21 | ((pts_stamp >> 29) & 0x6);
  99         dst[10+16] = (pts_stamp >> 22) & 0xff;
 100         dst[11+16] = 1 | ((pts_stamp >> 14) & 0xff);
 101         dst[12+16] = (pts_stamp >> 7) & 0xff;
 102         dst[13+16] = 1 | ((pts_stamp & 0x7f) << 1);
 103         cx->vbi.sliced_mpeg_size[idx] = sd + size;
 104 }
 105
 106 /* Compress raw VBI format, removes leading SAV codes and surplus space
 107    after the frame.  Returns new compressed size. */
 108 /* FIXME - this function ignores the input size. */
 109 static u32 compress_raw_buf(struct cx18 *cx, u8 *buf, u32 size, u32 hdr_size)
 110 {
 111         u32 line_size = vbi_active_samples;
 112         u32 lines = cx->vbi.count * 2;
 113         u8 *q = buf;
 114         u8 *p;
 115         int i;
 116
 117         /* Skip the header */
 118         buf += hdr_size;
 119
 120         for (i = 0; i < lines; i++) {
 121                 p = buf + i * line_size;
 122
 123                 /* Look for SAV code */
 124                 if (p[0] != 0xff || p[1] || p[2] ||
 125                     (p[3] != raw_vbi_sav_rp[0] &&
 126                      p[3] != raw_vbi_sav_rp[1]))
 127                         break;
 128                 if (i == lines - 1) {
 129                         /* last line is hdr_size bytes short - extrapolate it */
 130                         memcpy(q, p + 4, line_size - 4 - hdr_size);
 131                         q += line_size - 4 - hdr_size;
 132                         p += line_size - hdr_size - 1;
 133                         memset(q, (int) *p, hdr_size);
 134                 } else {
 135                         memcpy(q, p + 4, line_size - 4);
 136                         q += line_size - 4;
 137                 }
 138         }
 139         return lines * (line_size - 4);
 140 }
 141
 142 static u32 compress_sliced_buf(struct cx18 *cx, u8 *buf, u32 size,
 143                                const u32 hdr_size)
 144 {
 145         struct v4l2_decode_vbi_line vbi;
 146         int i;
 147         u32 line = 0;
 148         u32 line_size = cx->is_60hz ? vbi_hblank_samples_60Hz
 149                                     : vbi_hblank_samples_50Hz;
 150
 151         /* find the first valid line */
 152         for (i = hdr_size, buf += hdr_size; i < size; i++, buf++) {
 153                 if (buf[0] == 0xff && !buf[1] && !buf[2] &&
 154                     (buf[3] == sliced_vbi_eav_rp[0] ||
 155                      buf[3] == sliced_vbi_eav_rp[1]))
 156                         break;
 157         }
 158
 159         /*
 160          * The last line is short by hdr_size bytes, but for the remaining
 161          * checks against size, we pretend that it is not, by counting the
 162          * header bytes we knowingly skipped
 163          */
 164         size -= (i - hdr_size);
 165         if (size < line_size)
 166                 return line;
 167
 168         for (i = 0; i < size / line_size; i++) {
 169                 u8 *p = buf + i * line_size;
 170
 171                 /* Look for EAV code  */
 172                 if (p[0] != 0xff || p[1] || p[2] ||
 173                     (p[3] != sliced_vbi_eav_rp[0] &&
 174                      p[3] != sliced_vbi_eav_rp[1]))
 175                         continue;
 176                 vbi.p = p + 4;
 177                 v4l2_subdev_call(cx->sd_av, vbi, decode_vbi_line, &vbi);
 178                 if (vbi.type) {
 179                         cx->vbi.sliced_data[line].id = vbi.type;
 180                         cx->vbi.sliced_data[line].field = vbi.is_second_field;
 181                         cx->vbi.sliced_data[line].line = vbi.line;
 182                         memcpy(cx->vbi.sliced_data[line].data, vbi.p, 42);
 183                         line++;
 184                 }
 185         }
 186         return line;
 187 }
 188
 189 static void _cx18_process_vbi_data(struct cx18 *cx, struct cx18_buffer *buf)
 190 {
 191         /*
 192          * The CX23418 provides a 12 byte header in its raw VBI buffers to us:
 193          * 0x3fffffff [4 bytes of something] [4 byte presentation time stamp]
 194          */
 195         struct vbi_data_hdr {
 196                 __be32 magic;
 197                 __be32 unknown;
 198                 __be32 pts;
 199         } *hdr = (struct vbi_data_hdr *) buf->buf;
 200
 201         u8 *p = (u8 *) buf->buf;
 202         u32 size = buf->bytesused;
 203         u32 pts;
 204         int lines;
 205
 206         /*
 207          * The CX23418 sends us data that is 32 bit little-endian swapped,
 208          * but we want the raw VBI bytes in the order they were in the raster
 209          * line.  This has a side effect of making the header big endian
 210          */
 211         cx18_buf_swap(buf);
 212
 213         /* Raw VBI data */
 214         if (cx18_raw_vbi(cx)) {
 215
 216                 size = buf->bytesused =
 217                      compress_raw_buf(cx, p, size, sizeof(struct vbi_data_hdr));
 218
 219                 /*
 220                  * Hack needed for compatibility with old VBI software.
 221                  * Write the frame # at the last 4 bytes of the frame
 222                  */
 223                 p += size - 4;
 224                 memcpy(p, &cx->vbi.frame, 4);
 225                 cx->vbi.frame++;
 226                 return;
 227         }
 228
 229         /* Sliced VBI data with data insertion */
 230
 231         pts = (be32_to_cpu(hdr->magic) == 0x3fffffff) ? be32_to_cpu(hdr->pts)
 232                                                       : 0;
 233
 234         lines = compress_sliced_buf(cx, p, size, sizeof(struct vbi_data_hdr));
 235
 236         /* always return at least one empty line */
 237         if (lines == 0) {
 238                 cx->vbi.sliced_data[0].id = 0;
 239                 cx->vbi.sliced_data[0].line = 0;
 240                 cx->vbi.sliced_data[0].field = 0;
 241                 lines = 1;
 242         }
 243         buf->bytesused = size = lines * sizeof(cx->vbi.sliced_data[0]);
 244         memcpy(p, &cx->vbi.sliced_data[0], size);
 245
 246         if (cx->vbi.insert_mpeg)
 247                 copy_vbi_data(cx, lines, pts);
 248         cx->vbi.frame++;
 249 }
 250
 251 void cx18_process_vbi_data(struct cx18 *cx, struct cx18_mdl *mdl,
 252                            int streamtype)
 253 {
 254         struct cx18_buffer *buf;
 255         u32 orig_used;
 256
 257         if (streamtype != CX18_ENC_STREAM_TYPE_VBI)
 258                 return;
 259
 260         /*
 261          * Big assumption here:
 262          * Every buffer hooked to the MDL's buf_list is a complete VBI frame
 263          * that ends at the end of the buffer.
 264          *
 265          * To assume anything else would make the code in this file
 266          * more complex, or require extra memcpy()'s to make the
 267          * buffers satisfy the above assumption.  It's just simpler to set
 268          * up the encoder buffer transfers to make the assumption true.
 269          */
 270         list_for_each_entry(buf, &mdl->buf_list, list) {
 271                 orig_used = buf->bytesused;
 272                 if (orig_used == 0)
 273                         break;
 274                 _cx18_process_vbi_data(cx, buf);
 275                 mdl->bytesused -= (orig_used - buf->bytesused);
 276         }
 277 }