drivers/media/pci/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
  19 #include "cx18-driver.h"
  20 #include "cx18-vbi.h"
  21 #include "cx18-ioctl.h"
  22 #include "cx18-queue.h"
  23
  24 /*
  25  * Raster Reference/Protection (RP) bytes, used in Start/End Active
  26  * Video codes emitted from the digitzer in VIP 1.x mode, that flag the start
  27  * of VBI sample or VBI ancillary data regions in the digitial ratser line.
  28  *
  29  * Task FieldEven VerticalBlank HorizontalBlank 0 0 0 0
  30  */
  31 static const u8 raw_vbi_sav_rp[2] = { 0x20, 0x60 };    /* __V_, _FV_ */
  32 static const u8 sliced_vbi_eav_rp[2] = { 0xb0, 0xf0 }; /* T_VH, TFVH */
  33
  34 static void copy_vbi_data(struct cx18 *cx, int lines, u32 pts_stamp)
  35 {
  36         int line = 0;
  37         int i;
  38         u32 linemask[2] = { 0, 0 };
  39         unsigned short size;
  40         static const u8 mpeg_hdr_data[] = {
  41                 /* MPEG-2 Program Pack */
  42                 0x00, 0x00, 0x01, 0xba,             /* Prog Pack start code */
  43                 0x44, 0x00, 0x0c, 0x66, 0x24, 0x01, /* SCR, SCR Ext, markers */
  44                 0x01, 0xd1, 0xd3,                   /* Mux Rate, markers */
  45                 0xfa, 0xff, 0xff,                   /* Res, Suff cnt, Stuff */
  46                 /* MPEG-2 Private Stream 1 PES Packet */
  47                 0x00, 0x00, 0x01, 0xbd,             /* Priv Stream 1 start */
  48                 0x00, 0x1a,                         /* length */
  49                 0x84, 0x80, 0x07,                   /* flags, hdr data len */
  50                 0x21, 0x00, 0x5d, 0x63, 0xa7,       /* PTS, markers */
  51                 0xff, 0xff                          /* stuffing */
  52         };
  53         const int sd = sizeof(mpeg_hdr_data);   /* start of vbi data */
  54         int idx = cx->vbi.frame % CX18_VBI_FRAMES;
  55         u8 *dst = &cx->vbi.sliced_mpeg_data[idx][0];
  56
  57         for (i = 0; i < lines; i++) {
  58                 struct v4l2_sliced_vbi_data *sdata = cx->vbi.sliced_data + i;
  59                 int f, l;
  60
  61                 if (sdata->id == 0)
  62                         continue;
  63
  64                 l = sdata->line - 6;
  65                 f = sdata->field;
  66                 if (f)
  67                         l += 18;
  68                 if (l < 32)
  69                         linemask[0] |= (1 << l);
  70                 else
  71                         linemask[1] |= (1 << (l - 32));
  72                 dst[sd + 12 + line * 43] = cx18_service2vbi(sdata->id);
  73                 memcpy(dst + sd + 12 + line * 43 + 1, sdata->data, 42);
  74                 line++;
  75         }
  76         memcpy(dst, mpeg_hdr_data, sizeof(mpeg_hdr_data));
  77         if (line == 36) {
  78                 /* All lines are used, so there is no space for the linemask
  79                    (the max size of the VBI data is 36 * 43 + 4 bytes).
  80                    So in this case we use the magic number 'ITV0'. */
  81                 memcpy(dst + sd, "ITV0", 4);
  82                 memmove(dst + sd + 4, dst + sd + 12, line * 43);
  83                 size = 4 + ((43 * line + 3) & ~3);
  84         } else {
  85                 memcpy(dst + sd, "itv0", 4);
  86                 cpu_to_le32s(&linemask[0]);
  87                 cpu_to_le32s(&linemask[1]);
  88                 memcpy(dst + sd + 4, &linemask[0], 8);
  89                 size = 12 + ((43 * line + 3) & ~3);
  90         }
  91         dst[4+16] = (size + 10) >> 8;
  92         dst[5+16] = (size + 10) & 0xff;
  93         dst[9+16] = 0x21 | ((pts_stamp >> 29) & 0x6);
  94         dst[10+16] = (pts_stamp >> 22) & 0xff;
  95         dst[11+16] = 1 | ((pts_stamp >> 14) & 0xff);
  96         dst[12+16] = (pts_stamp >> 7) & 0xff;
  97         dst[13+16] = 1 | ((pts_stamp & 0x7f) << 1);
  98         cx->vbi.sliced_mpeg_size[idx] = sd + size;
  99 }
 100
 101 /* Compress raw VBI format, removes leading SAV codes and surplus space
 102    after the frame.  Returns new compressed size. */
 103 /* FIXME - this function ignores the input size. */
 104 static u32 compress_raw_buf(struct cx18 *cx, u8 *buf, u32 size, u32 hdr_size)
 105 {
 106         u32 line_size = VBI_ACTIVE_SAMPLES;
 107         u32 lines = cx->vbi.count * 2;
 108         u8 *q = buf;
 109         u8 *p;
 110         int i;
 111
 112         /* Skip the header */
 113         buf += hdr_size;
 114
 115         for (i = 0; i < lines; i++) {
 116                 p = buf + i * line_size;
 117
 118                 /* Look for SAV code */
 119                 if (p[0] != 0xff || p[1] || p[2] ||
 120                     (p[3] != raw_vbi_sav_rp[0] &&
 121                      p[3] != raw_vbi_sav_rp[1]))
 122                         break;
 123                 if (i == lines - 1) {
 124                         /* last line is hdr_size bytes short - extrapolate it */
 125                         memcpy(q, p + 4, line_size - 4 - hdr_size);
 126                         q += line_size - 4 - hdr_size;
 127                         p += line_size - hdr_size - 1;
 128                         memset(q, (int) *p, hdr_size);
 129                 } else {
 130                         memcpy(q, p + 4, line_size - 4);
 131                         q += line_size - 4;
 132                 }
 133         }
 134         return lines * (line_size - 4);
 135 }
 136
 137 static u32 compress_sliced_buf(struct cx18 *cx, u8 *buf, u32 size,
 138                                const u32 hdr_size)
 139 {
 140         struct v4l2_decode_vbi_line vbi;
 141         int i;
 142         u32 line = 0;
 143         u32 line_size = cx->is_60hz ? VBI_HBLANK_SAMPLES_60HZ
 144                                     : VBI_HBLANK_SAMPLES_50HZ;
 145
 146         /* find the first valid line */
 147         for (i = hdr_size, buf += hdr_size; i < size; i++, buf++) {
 148                 if (buf[0] == 0xff && !buf[1] && !buf[2] &&
 149                     (buf[3] == sliced_vbi_eav_rp[0] ||
 150                      buf[3] == sliced_vbi_eav_rp[1]))
 151                         break;
 152         }
 153
 154         /*
 155          * The last line is short by hdr_size bytes, but for the remaining
 156          * checks against size, we pretend that it is not, by counting the
 157          * header bytes we knowingly skipped
 158          */
 159         size -= (i - hdr_size);
 160         if (size < line_size)
 161                 return line;
 162
 163         for (i = 0; i < size / line_size; i++) {
 164                 u8 *p = buf + i * line_size;
 165
 166                 /* Look for EAV code  */
 167                 if (p[0] != 0xff || p[1] || p[2] ||
 168                     (p[3] != sliced_vbi_eav_rp[0] &&
 169                      p[3] != sliced_vbi_eav_rp[1]))
 170                         continue;
 171                 vbi.p = p + 4;
 172                 v4l2_subdev_call(cx->sd_av, vbi, decode_vbi_line, &vbi);
 173                 if (vbi.type) {
 174                         cx->vbi.sliced_data[line].id = vbi.type;
 175                         cx->vbi.sliced_data[line].field = vbi.is_second_field;
 176                         cx->vbi.sliced_data[line].line = vbi.line;
 177                         memcpy(cx->vbi.sliced_data[line].data, vbi.p, 42);
 178                         line++;
 179                 }
 180         }
 181         return line;
 182 }
 183
 184 static void _cx18_process_vbi_data(struct cx18 *cx, struct cx18_buffer *buf)
 185 {
 186         /*
 187          * The CX23418 provides a 12 byte header in its raw VBI buffers to us:
 188          * 0x3fffffff [4 bytes of something] [4 byte presentation time stamp]
 189          */
 190         struct vbi_data_hdr {
 191                 __be32 magic;
 192                 __be32 unknown;
 193                 __be32 pts;
 194         } *hdr = (struct vbi_data_hdr *) buf->buf;
 195
 196         u8 *p = (u8 *) buf->buf;
 197         u32 size = buf->bytesused;
 198         u32 pts;
 199         int lines;
 200
 201         /*
 202          * The CX23418 sends us data that is 32 bit little-endian swapped,
 203          * but we want the raw VBI bytes in the order they were in the raster
 204          * line.  This has a side effect of making the header big endian
 205          */
 206         cx18_buf_swap(buf);
 207
 208         /* Raw VBI data */
 209         if (cx18_raw_vbi(cx)) {
 210
 211                 size = buf->bytesused =
 212                      compress_raw_buf(cx, p, size, sizeof(struct vbi_data_hdr));
 213
 214                 /*
 215                  * Hack needed for compatibility with old VBI software.
 216                  * Write the frame # at the last 4 bytes of the frame
 217                  */
 218                 p += size - 4;
 219                 memcpy(p, &cx->vbi.frame, 4);
 220                 cx->vbi.frame++;
 221                 return;
 222         }
 223
 224         /* Sliced VBI data with data insertion */
 225
 226         pts = (be32_to_cpu(hdr->magic) == 0x3fffffff) ? be32_to_cpu(hdr->pts)
 227                                                       : 0;
 228
 229         lines = compress_sliced_buf(cx, p, size, sizeof(struct vbi_data_hdr));
 230
 231         /* always return at least one empty line */
 232         if (lines == 0) {
 233                 cx->vbi.sliced_data[0].id = 0;
 234                 cx->vbi.sliced_data[0].line = 0;
 235                 cx->vbi.sliced_data[0].field = 0;
 236                 lines = 1;
 237         }
 238         buf->bytesused = size = lines * sizeof(cx->vbi.sliced_data[0]);
 239         memcpy(p, &cx->vbi.sliced_data[0], size);
 240
 241         if (cx->vbi.insert_mpeg)
 242                 copy_vbi_data(cx, lines, pts);
 243         cx->vbi.frame++;
 244 }
 245
 246 void cx18_process_vbi_data(struct cx18 *cx, struct cx18_mdl *mdl,
 247                            int streamtype)
 248 {
 249         struct cx18_buffer *buf;
 250         u32 orig_used;
 251
 252         if (streamtype != CX18_ENC_STREAM_TYPE_VBI)
 253                 return;
 254
 255         /*
 256          * Big assumption here:
 257          * Every buffer hooked to the MDL's buf_list is a complete VBI frame
 258          * that ends at the end of the buffer.
 259          *
 260          * To assume anything else would make the code in this file
 261          * more complex, or require extra memcpy()'s to make the
 262          * buffers satisfy the above assumption.  It's just simpler to set
 263          * up the encoder buffer transfers to make the assumption true.
 264          */
 265         list_for_each_entry(buf, &mdl->buf_list, list) {
 266                 orig_used = buf->bytesused;
 267                 if (orig_used == 0)
 268                         break;
 269                 _cx18_process_vbi_data(cx, buf);
 270                 mdl->bytesused -= (orig_used - buf->bytesused);
 271         }
 272 }