drivers/media/pci/cx18/cx18-av-vbi.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  cx18 ADEC VBI functions
   4  *
   5  *  Derived from cx25840-vbi.c
   6  *
   7  *  Copyright (C) 2007  Hans Verkuil <hverkuil@xs4all.nl>
   8  */
   9
  10
  11 #include "cx18-driver.h"
  12
  13 /*
  14  * For sliced VBI output, we set up to use VIP-1.1, 8-bit mode,
  15  * NN counts 1 byte Dwords, an IDID with the VBI line # in it.
  16  * Thus, according to the VIP-2 Spec, our VBI ancillary data lines
  17  * (should!) look like:
  18  *      4 byte EAV code:          0xff 0x00 0x00 0xRP
  19  *      unknown number of possible idle bytes
  20  *      3 byte Anc data preamble: 0x00 0xff 0xff
  21  *      1 byte data identifier:   ne010iii (parity bits, 010, DID bits)
  22  *      1 byte secondary data id: nessssss (parity bits, SDID bits)
  23  *      1 byte data word count:   necccccc (parity bits, NN Dword count)
  24  *      2 byte Internal DID:      VBI-line-# 0x80
  25  *      NN data bytes
  26  *      1 byte checksum
  27  *      Fill bytes needed to fil out to 4*NN bytes of payload
  28  *
  29  * The RP codes for EAVs when in VIP-1.1 mode, not in raw mode, &
  30  * in the vertical blanking interval are:
  31  *      0xb0 (Task         0 VerticalBlank HorizontalBlank 0 0 0 0)
  32  *      0xf0 (Task EvenField VerticalBlank HorizontalBlank 0 0 0 0)
  33  *
  34  * Since the V bit is only allowed to toggle in the EAV RP code, just
  35  * before the first active region line and for active lines, they are:
  36  *      0x90 (Task         0 0 HorizontalBlank 0 0 0 0)
  37  *      0xd0 (Task EvenField 0 HorizontalBlank 0 0 0 0)
  38  *
  39  * The user application DID bytes we care about are:
  40  *      0x91 (1 0 010        0 !ActiveLine AncDataPresent)
  41  *      0x55 (0 1 010 2ndField !ActiveLine AncDataPresent)
  42  *
  43  */
  44 static const u8 sliced_vbi_did[2] = { 0x91, 0x55 };
  45
  46 struct vbi_anc_data {
  47         /* u8 eav[4]; */
  48         /* u8 idle[]; Variable number of idle bytes */
  49         u8 preamble[3];
  50         u8 did;
  51         u8 sdid;
  52         u8 data_count;
  53         u8 idid[2];
  54         u8 payload[1]; /* data_count of payload */
  55         /* u8 checksum; */
  56         /* u8 fill[]; Variable number of fill bytes */
  57 };
  58
  59 static int odd_parity(u8 c)
  60 {
  61         c ^= (c >> 4);
  62         c ^= (c >> 2);
  63         c ^= (c >> 1);
  64
  65         return c & 1;
  66 }
  67
  68 static int decode_vps(u8 *dst, u8 *p)
  69 {
  70         static const u8 biphase_tbl[] = {
  71                 0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
  72                 0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
  73                 0xd2, 0x5a, 0x52, 0xd2, 0x96, 0x1e, 0x16, 0x96,
  74                 0x92, 0x1a, 0x12, 0x92, 0xd2, 0x5a, 0x52, 0xd2,
  75                 0xd0, 0x58, 0x50, 0xd0, 0x94, 0x1c, 0x14, 0x94,
  76                 0x90, 0x18, 0x10, 0x90, 0xd0, 0x58, 0x50, 0xd0,
  77                 0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
  78                 0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
  79                 0xe1, 0x69, 0x61, 0xe1, 0xa5, 0x2d, 0x25, 0xa5,
  80                 0xa1, 0x29, 0x21, 0xa1, 0xe1, 0x69, 0x61, 0xe1,
  81                 0xc3, 0x4b, 0x43, 0xc3, 0x87, 0x0f, 0x07, 0x87,
  82                 0x83, 0x0b, 0x03, 0x83, 0xc3, 0x4b, 0x43, 0xc3,
  83                 0xc1, 0x49, 0x41, 0xc1, 0x85, 0x0d, 0x05, 0x85,
  84                 0x81, 0x09, 0x01, 0x81, 0xc1, 0x49, 0x41, 0xc1,
  85                 0xe1, 0x69, 0x61, 0xe1, 0xa5, 0x2d, 0x25, 0xa5,
  86                 0xa1, 0x29, 0x21, 0xa1, 0xe1, 0x69, 0x61, 0xe1,
  87                 0xe0, 0x68, 0x60, 0xe0, 0xa4, 0x2c, 0x24, 0xa4,
  88                 0xa0, 0x28, 0x20, 0xa0, 0xe0, 0x68, 0x60, 0xe0,
  89                 0xc2, 0x4a, 0x42, 0xc2, 0x86, 0x0e, 0x06, 0x86,
  90                 0x82, 0x0a, 0x02, 0x82, 0xc2, 0x4a, 0x42, 0xc2,
  91                 0xc0, 0x48, 0x40, 0xc0, 0x84, 0x0c, 0x04, 0x84,
  92                 0x80, 0x08, 0x00, 0x80, 0xc0, 0x48, 0x40, 0xc0,
  93                 0xe0, 0x68, 0x60, 0xe0, 0xa4, 0x2c, 0x24, 0xa4,
  94                 0xa0, 0x28, 0x20, 0xa0, 0xe0, 0x68, 0x60, 0xe0,
  95                 0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
  96                 0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
  97                 0xd2, 0x5a, 0x52, 0xd2, 0x96, 0x1e, 0x16, 0x96,
  98                 0x92, 0x1a, 0x12, 0x92, 0xd2, 0x5a, 0x52, 0xd2,
  99                 0xd0, 0x58, 0x50, 0xd0, 0x94, 0x1c, 0x14, 0x94,
 100                 0x90, 0x18, 0x10, 0x90, 0xd0, 0x58, 0x50, 0xd0,
 101                 0xf0, 0x78, 0x70, 0xf0, 0xb4, 0x3c, 0x34, 0xb4,
 102                 0xb0, 0x38, 0x30, 0xb0, 0xf0, 0x78, 0x70, 0xf0,
 103         };
 104
 105         u8 c, err = 0;
 106         int i;
 107
 108         for (i = 0; i < 2 * 13; i += 2) {
 109                 err |= biphase_tbl[p[i]] | biphase_tbl[p[i + 1]];
 110                 c = (biphase_tbl[p[i + 1]] & 0xf) |
 111                     ((biphase_tbl[p[i]] & 0xf) << 4);
 112                 dst[i / 2] = c;
 113         }
 114
 115         return err & 0xf0;
 116 }
 117
 118 int cx18_av_g_sliced_fmt(struct v4l2_subdev *sd, struct v4l2_sliced_vbi_format *svbi)
 119 {
 120         struct cx18 *cx = v4l2_get_subdevdata(sd);
 121         struct cx18_av_state *state = &cx->av_state;
 122         static const u16 lcr2vbi[] = {
 123                 0, V4L2_SLICED_TELETEXT_B, 0,   /* 1 */
 124                 0, V4L2_SLICED_WSS_625, 0,      /* 4 */
 125                 V4L2_SLICED_CAPTION_525,        /* 6 */
 126                 0, 0, V4L2_SLICED_VPS, 0, 0,    /* 9 */
 127                 0, 0, 0, 0
 128         };
 129         int is_pal = !(state->std & V4L2_STD_525_60);
 130         int i;
 131
 132         memset(svbi->service_lines, 0, sizeof(svbi->service_lines));
 133         svbi->service_set = 0;
 134
 135         /* we're done if raw VBI is active */
 136         if ((cx18_av_read(cx, 0x404) & 0x10) == 0)
 137                 return 0;
 138
 139         if (is_pal) {
 140                 for (i = 7; i <= 23; i++) {
 141                         u8 v = cx18_av_read(cx, 0x424 + i - 7);
 142
 143                         svbi->service_lines[0][i] = lcr2vbi[v >> 4];
 144                         svbi->service_lines[1][i] = lcr2vbi[v & 0xf];
 145                         svbi->service_set |= svbi->service_lines[0][i] |
 146                                 svbi->service_lines[1][i];
 147                 }
 148         } else {
 149                 for (i = 10; i <= 21; i++) {
 150                         u8 v = cx18_av_read(cx, 0x424 + i - 10);
 151
 152                         svbi->service_lines[0][i] = lcr2vbi[v >> 4];
 153                         svbi->service_lines[1][i] = lcr2vbi[v & 0xf];
 154                         svbi->service_set |= svbi->service_lines[0][i] |
 155                                 svbi->service_lines[1][i];
 156                 }
 157         }
 158         return 0;
 159 }
 160
 161 int cx18_av_s_raw_fmt(struct v4l2_subdev *sd, struct v4l2_vbi_format *fmt)
 162 {
 163         struct cx18 *cx = v4l2_get_subdevdata(sd);
 164         struct cx18_av_state *state = &cx->av_state;
 165
 166         /* Setup standard */
 167         cx18_av_std_setup(cx);
 168
 169         /* VBI Offset */
 170         cx18_av_write(cx, 0x47f, state->slicer_line_delay);
 171         cx18_av_write(cx, 0x404, 0x2e);
 172         return 0;
 173 }
 174
 175 int cx18_av_s_sliced_fmt(struct v4l2_subdev *sd, struct v4l2_sliced_vbi_format *svbi)
 176 {
 177         struct cx18 *cx = v4l2_get_subdevdata(sd);
 178         struct cx18_av_state *state = &cx->av_state;
 179         int is_pal = !(state->std & V4L2_STD_525_60);
 180         int i, x;
 181         u8 lcr[24];
 182
 183         for (x = 0; x <= 23; x++)
 184                 lcr[x] = 0x00;
 185
 186         /* Setup standard */
 187         cx18_av_std_setup(cx);
 188
 189         /* Sliced VBI */
 190         cx18_av_write(cx, 0x404, 0x32); /* Ancillary data */
 191         cx18_av_write(cx, 0x406, 0x13);
 192         cx18_av_write(cx, 0x47f, state->slicer_line_delay);
 193
 194         /* Force impossible lines to 0 */
 195         if (is_pal) {
 196                 for (i = 0; i <= 6; i++)
 197                         svbi->service_lines[0][i] =
 198                                 svbi->service_lines[1][i] = 0;
 199         } else {
 200                 for (i = 0; i <= 9; i++)
 201                         svbi->service_lines[0][i] =
 202                                 svbi->service_lines[1][i] = 0;
 203
 204                 for (i = 22; i <= 23; i++)
 205                         svbi->service_lines[0][i] =
 206                                 svbi->service_lines[1][i] = 0;
 207         }
 208
 209         /* Build register values for requested service lines */
 210         for (i = 7; i <= 23; i++) {
 211                 for (x = 0; x <= 1; x++) {
 212                         switch (svbi->service_lines[1-x][i]) {
 213                         case V4L2_SLICED_TELETEXT_B:
 214                                 lcr[i] |= 1 << (4 * x);
 215                                 break;
 216                         case V4L2_SLICED_WSS_625:
 217                                 lcr[i] |= 4 << (4 * x);
 218                                 break;
 219                         case V4L2_SLICED_CAPTION_525:
 220                                 lcr[i] |= 6 << (4 * x);
 221                                 break;
 222                         case V4L2_SLICED_VPS:
 223                                 lcr[i] |= 9 << (4 * x);
 224                                 break;
 225                         }
 226                 }
 227         }
 228
 229         if (is_pal) {
 230                 for (x = 1, i = 0x424; i <= 0x434; i++, x++)
 231                         cx18_av_write(cx, i, lcr[6 + x]);
 232         } else {
 233                 for (x = 1, i = 0x424; i <= 0x430; i++, x++)
 234                         cx18_av_write(cx, i, lcr[9 + x]);
 235                 for (i = 0x431; i <= 0x434; i++)
 236                         cx18_av_write(cx, i, 0);
 237         }
 238
 239         cx18_av_write(cx, 0x43c, 0x16);
 240         /* Should match vblank set in cx18_av_std_setup() */
 241         cx18_av_write(cx, 0x474, is_pal ? 38 : 26);
 242         return 0;
 243 }
 244
 245 int cx18_av_decode_vbi_line(struct v4l2_subdev *sd,
 246                                    struct v4l2_decode_vbi_line *vbi)
 247 {
 248         struct cx18 *cx = v4l2_get_subdevdata(sd);
 249         struct cx18_av_state *state = &cx->av_state;
 250         struct vbi_anc_data *anc = (struct vbi_anc_data *)vbi->p;
 251         u8 *p;
 252         int did, sdid, l, err = 0;
 253
 254         /*
 255          * Check for the ancillary data header for sliced VBI
 256          */
 257         if (anc->preamble[0] ||
 258                         anc->preamble[1] != 0xff || anc->preamble[2] != 0xff ||
 259                         (anc->did != sliced_vbi_did[0] &&
 260                          anc->did != sliced_vbi_did[1])) {
 261                 vbi->line = vbi->type = 0;
 262                 return 0;
 263         }
 264
 265         did = anc->did;
 266         sdid = anc->sdid & 0xf;
 267         l = anc->idid[0] & 0x3f;
 268         l += state->slicer_line_offset;
 269         p = anc->payload;
 270
 271         /* Decode the SDID set by the slicer */
 272         switch (sdid) {
 273         case 1:
 274                 sdid = V4L2_SLICED_TELETEXT_B;
 275                 break;
 276         case 4:
 277                 sdid = V4L2_SLICED_WSS_625;
 278                 break;
 279         case 6:
 280                 sdid = V4L2_SLICED_CAPTION_525;
 281                 err = !odd_parity(p[0]) || !odd_parity(p[1]);
 282                 break;
 283         case 9:
 284                 sdid = V4L2_SLICED_VPS;
 285                 if (decode_vps(p, p) != 0)
 286                         err = 1;
 287                 break;
 288         default:
 289                 sdid = 0;
 290                 err = 1;
 291                 break;
 292         }
 293
 294         vbi->type = err ? 0 : sdid;
 295         vbi->line = err ? 0 : l;
 296         vbi->is_second_field = err ? 0 : (did == sliced_vbi_did[1]);
 297         vbi->p = p;
 298         return 0;
 299 }