drivers/media/dvb-frontends/au8522_dig.c

   1 /*
   2     Auvitek AU8522 QAM/8VSB demodulator driver
   3
   4     Copyright (C) 2008 Steven Toth <stoth@linuxtv.org>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19
  20 */
  21
  22 #include <linux/kernel.h>
  23 #include <linux/init.h>
  24 #include <linux/module.h>
  25 #include <linux/string.h>
  26 #include <linux/delay.h>
  27 #include "dvb_frontend.h"
  28 #include "au8522.h"
  29 #include "au8522_priv.h"
  30
  31 static int debug;
  32
  33 #define dprintk(arg...)\
  34         do { if (debug)\
  35                 printk(arg);\
  36         } while (0)
  37
  38 struct mse2snr_tab {
  39         u16 val;
  40         u16 data;
  41 };
  42
  43 /* VSB SNR lookup table */
  44 static struct mse2snr_tab vsb_mse2snr_tab[] = {
  45         {   0, 270 },
  46         {   2, 250 },
  47         {   3, 240 },
  48         {   5, 230 },
  49         {   7, 220 },
  50         {   9, 210 },
  51         {  12, 200 },
  52         {  13, 195 },
  53         {  15, 190 },
  54         {  17, 185 },
  55         {  19, 180 },
  56         {  21, 175 },
  57         {  24, 170 },
  58         {  27, 165 },
  59         {  31, 160 },
  60         {  32, 158 },
  61         {  33, 156 },
  62         {  36, 152 },
  63         {  37, 150 },
  64         {  39, 148 },
  65         {  40, 146 },
  66         {  41, 144 },
  67         {  43, 142 },
  68         {  44, 140 },
  69         {  48, 135 },
  70         {  50, 130 },
  71         {  43, 142 },
  72         {  53, 125 },
  73         {  56, 120 },
  74         { 256, 115 },
  75 };
  76
  77 /* QAM64 SNR lookup table */
  78 static struct mse2snr_tab qam64_mse2snr_tab[] = {
  79         {  15,   0 },
  80         {  16, 290 },
  81         {  17, 288 },
  82         {  18, 286 },
  83         {  19, 284 },
  84         {  20, 282 },
  85         {  21, 281 },
  86         {  22, 279 },
  87         {  23, 277 },
  88         {  24, 275 },
  89         {  25, 273 },
  90         {  26, 271 },
  91         {  27, 269 },
  92         {  28, 268 },
  93         {  29, 266 },
  94         {  30, 264 },
  95         {  31, 262 },
  96         {  32, 260 },
  97         {  33, 259 },
  98         {  34, 258 },
  99         {  35, 256 },
 100         {  36, 255 },
 101         {  37, 254 },
 102         {  38, 252 },
 103         {  39, 251 },
 104         {  40, 250 },
 105         {  41, 249 },
 106         {  42, 248 },
 107         {  43, 246 },
 108         {  44, 245 },
 109         {  45, 244 },
 110         {  46, 242 },
 111         {  47, 241 },
 112         {  48, 240 },
 113         {  50, 239 },
 114         {  51, 238 },
 115         {  53, 237 },
 116         {  54, 236 },
 117         {  56, 235 },
 118         {  57, 234 },
 119         {  59, 233 },
 120         {  60, 232 },
 121         {  62, 231 },
 122         {  63, 230 },
 123         {  65, 229 },
 124         {  67, 228 },
 125         {  68, 227 },
 126         {  70, 226 },
 127         {  71, 225 },
 128         {  73, 224 },
 129         {  74, 223 },
 130         {  76, 222 },
 131         {  78, 221 },
 132         {  80, 220 },
 133         {  82, 219 },
 134         {  85, 218 },
 135         {  88, 217 },
 136         {  90, 216 },
 137         {  92, 215 },
 138         {  93, 214 },
 139         {  94, 212 },
 140         {  95, 211 },
 141         {  97, 210 },
 142         {  99, 209 },
 143         { 101, 208 },
 144         { 102, 207 },
 145         { 104, 206 },
 146         { 107, 205 },
 147         { 111, 204 },
 148         { 114, 203 },
 149         { 118, 202 },
 150         { 122, 201 },
 151         { 125, 200 },
 152         { 128, 199 },
 153         { 130, 198 },
 154         { 132, 197 },
 155         { 256, 190 },
 156 };
 157
 158 /* QAM256 SNR lookup table */
 159 static struct mse2snr_tab qam256_mse2snr_tab[] = {
 160         {  15,   0 },
 161         {  16, 400 },
 162         {  17, 398 },
 163         {  18, 396 },
 164         {  19, 394 },
 165         {  20, 392 },
 166         {  21, 390 },
 167         {  22, 388 },
 168         {  23, 386 },
 169         {  24, 384 },
 170         {  25, 382 },
 171         {  26, 380 },
 172         {  27, 379 },
 173         {  28, 378 },
 174         {  29, 377 },
 175         {  30, 376 },
 176         {  31, 375 },
 177         {  32, 374 },
 178         {  33, 373 },
 179         {  34, 372 },
 180         {  35, 371 },
 181         {  36, 370 },
 182         {  37, 362 },
 183         {  38, 354 },
 184         {  39, 346 },
 185         {  40, 338 },
 186         {  41, 330 },
 187         {  42, 328 },
 188         {  43, 326 },
 189         {  44, 324 },
 190         {  45, 322 },
 191         {  46, 320 },
 192         {  47, 319 },
 193         {  48, 318 },
 194         {  49, 317 },
 195         {  50, 316 },
 196         {  51, 315 },
 197         {  52, 314 },
 198         {  53, 313 },
 199         {  54, 312 },
 200         {  55, 311 },
 201         {  56, 310 },
 202         {  57, 308 },
 203         {  58, 306 },
 204         {  59, 304 },
 205         {  60, 302 },
 206         {  61, 300 },
 207         {  62, 298 },
 208         {  65, 295 },
 209         {  68, 294 },
 210         {  70, 293 },
 211         {  73, 292 },
 212         {  76, 291 },
 213         {  78, 290 },
 214         {  79, 289 },
 215         {  81, 288 },
 216         {  82, 287 },
 217         {  83, 286 },
 218         {  84, 285 },
 219         {  85, 284 },
 220         {  86, 283 },
 221         {  88, 282 },
 222         {  89, 281 },
 223         { 256, 280 },
 224 };
 225
 226 static int au8522_mse2snr_lookup(struct mse2snr_tab *tab, int sz, int mse,
 227                                  u16 *snr)
 228 {
 229         int i, ret = -EINVAL;
 230         dprintk("%s()\n", __func__);
 231
 232         for (i = 0; i < sz; i++) {
 233                 if (mse < tab[i].val) {
 234                         *snr = tab[i].data;
 235                         ret = 0;
 236                         break;
 237                 }
 238         }
 239         dprintk("%s() snr=%d\n", __func__, *snr);
 240         return ret;
 241 }
 242
 243 static int au8522_set_if(struct dvb_frontend *fe, enum au8522_if_freq if_freq)
 244 {
 245         struct au8522_state *state = fe->demodulator_priv;
 246         u8 r0b5, r0b6, r0b7;
 247         char *ifmhz;
 248
 249         switch (if_freq) {
 250         case AU8522_IF_3_25MHZ:
 251                 ifmhz = "3.25";
 252                 r0b5 = 0x00;
 253                 r0b6 = 0x3d;
 254                 r0b7 = 0xa0;
 255                 break;
 256         case AU8522_IF_4MHZ:
 257                 ifmhz = "4.00";
 258                 r0b5 = 0x00;
 259                 r0b6 = 0x4b;
 260                 r0b7 = 0xd9;
 261                 break;
 262         case AU8522_IF_6MHZ:
 263                 ifmhz = "6.00";
 264                 r0b5 = 0xfb;
 265                 r0b6 = 0x8e;
 266                 r0b7 = 0x39;
 267                 break;
 268         default:
 269                 dprintk("%s() IF Frequency not supported\n", __func__);
 270                 return -EINVAL;
 271         }
 272         dprintk("%s() %s MHz\n", __func__, ifmhz);
 273         au8522_writereg(state, 0x80b5, r0b5);
 274         au8522_writereg(state, 0x80b6, r0b6);
 275         au8522_writereg(state, 0x80b7, r0b7);
 276
 277         return 0;
 278 }
 279
 280 /* VSB Modulation table */
 281 static struct {
 282         u16 reg;
 283         u16 data;
 284 } VSB_mod_tab[] = {
 285         { 0x8090, 0x84 },
 286         { 0x4092, 0x11 },
 287         { 0x2005, 0x00 },
 288         { 0x8091, 0x80 },
 289         { 0x80a3, 0x0c },
 290         { 0x80a4, 0xe8 },
 291         { 0x8081, 0xc4 },
 292         { 0x80a5, 0x40 },
 293         { 0x80a7, 0x40 },
 294         { 0x80a6, 0x67 },
 295         { 0x8262, 0x20 },
 296         { 0x821c, 0x30 },
 297         { 0x80d8, 0x1a },
 298         { 0x8227, 0xa0 },
 299         { 0x8121, 0xff },
 300         { 0x80a8, 0xf0 },
 301         { 0x80a9, 0x05 },
 302         { 0x80aa, 0x77 },
 303         { 0x80ab, 0xf0 },
 304         { 0x80ac, 0x05 },
 305         { 0x80ad, 0x77 },
 306         { 0x80ae, 0x41 },
 307         { 0x80af, 0x66 },
 308         { 0x821b, 0xcc },
 309         { 0x821d, 0x80 },
 310         { 0x80a4, 0xe8 },
 311         { 0x8231, 0x13 },
 312 };
 313
 314 /* QAM64 Modulation table */
 315 static struct {
 316         u16 reg;
 317         u16 data;
 318 } QAM64_mod_tab[] = {
 319         { 0x00a3, 0x09 },
 320         { 0x00a4, 0x00 },
 321         { 0x0081, 0xc4 },
 322         { 0x00a5, 0x40 },
 323         { 0x00aa, 0x77 },
 324         { 0x00ad, 0x77 },
 325         { 0x00a6, 0x67 },
 326         { 0x0262, 0x20 },
 327         { 0x021c, 0x30 },
 328         { 0x00b8, 0x3e },
 329         { 0x00b9, 0xf0 },
 330         { 0x00ba, 0x01 },
 331         { 0x00bb, 0x18 },
 332         { 0x00bc, 0x50 },
 333         { 0x00bd, 0x00 },
 334         { 0x00be, 0xea },
 335         { 0x00bf, 0xef },
 336         { 0x00c0, 0xfc },
 337         { 0x00c1, 0xbd },
 338         { 0x00c2, 0x1f },
 339         { 0x00c3, 0xfc },
 340         { 0x00c4, 0xdd },
 341         { 0x00c5, 0xaf },
 342         { 0x00c6, 0x00 },
 343         { 0x00c7, 0x38 },
 344         { 0x00c8, 0x30 },
 345         { 0x00c9, 0x05 },
 346         { 0x00ca, 0x4a },
 347         { 0x00cb, 0xd0 },
 348         { 0x00cc, 0x01 },
 349         { 0x00cd, 0xd9 },
 350         { 0x00ce, 0x6f },
 351         { 0x00cf, 0xf9 },
 352         { 0x00d0, 0x70 },
 353         { 0x00d1, 0xdf },
 354         { 0x00d2, 0xf7 },
 355         { 0x00d3, 0xc2 },
 356         { 0x00d4, 0xdf },
 357         { 0x00d5, 0x02 },
 358         { 0x00d6, 0x9a },
 359         { 0x00d7, 0xd0 },
 360         { 0x0250, 0x0d },
 361         { 0x0251, 0xcd },
 362         { 0x0252, 0xe0 },
 363         { 0x0253, 0x05 },
 364         { 0x0254, 0xa7 },
 365         { 0x0255, 0xff },
 366         { 0x0256, 0xed },
 367         { 0x0257, 0x5b },
 368         { 0x0258, 0xae },
 369         { 0x0259, 0xe6 },
 370         { 0x025a, 0x3d },
 371         { 0x025b, 0x0f },
 372         { 0x025c, 0x0d },
 373         { 0x025d, 0xea },
 374         { 0x025e, 0xf2 },
 375         { 0x025f, 0x51 },
 376         { 0x0260, 0xf5 },
 377         { 0x0261, 0x06 },
 378         { 0x021a, 0x00 },
 379         { 0x0546, 0x40 },
 380         { 0x0210, 0xc7 },
 381         { 0x0211, 0xaa },
 382         { 0x0212, 0xab },
 383         { 0x0213, 0x02 },
 384         { 0x0502, 0x00 },
 385         { 0x0121, 0x04 },
 386         { 0x0122, 0x04 },
 387         { 0x052e, 0x10 },
 388         { 0x00a4, 0xca },
 389         { 0x00a7, 0x40 },
 390         { 0x0526, 0x01 },
 391 };
 392
 393 /* QAM256 Modulation table */
 394 static struct {
 395         u16 reg;
 396         u16 data;
 397 } QAM256_mod_tab[] = {
 398         { 0x80a3, 0x09 },
 399         { 0x80a4, 0x00 },
 400         { 0x8081, 0xc4 },
 401         { 0x80a5, 0x40 },
 402         { 0x80aa, 0x77 },
 403         { 0x80ad, 0x77 },
 404         { 0x80a6, 0x67 },
 405         { 0x8262, 0x20 },
 406         { 0x821c, 0x30 },
 407         { 0x80b8, 0x3e },
 408         { 0x80b9, 0xf0 },
 409         { 0x80ba, 0x01 },
 410         { 0x80bb, 0x18 },
 411         { 0x80bc, 0x50 },
 412         { 0x80bd, 0x00 },
 413         { 0x80be, 0xea },
 414         { 0x80bf, 0xef },
 415         { 0x80c0, 0xfc },
 416         { 0x80c1, 0xbd },
 417         { 0x80c2, 0x1f },
 418         { 0x80c3, 0xfc },
 419         { 0x80c4, 0xdd },
 420         { 0x80c5, 0xaf },
 421         { 0x80c6, 0x00 },
 422         { 0x80c7, 0x38 },
 423         { 0x80c8, 0x30 },
 424         { 0x80c9, 0x05 },
 425         { 0x80ca, 0x4a },
 426         { 0x80cb, 0xd0 },
 427         { 0x80cc, 0x01 },
 428         { 0x80cd, 0xd9 },
 429         { 0x80ce, 0x6f },
 430         { 0x80cf, 0xf9 },
 431         { 0x80d0, 0x70 },
 432         { 0x80d1, 0xdf },
 433         { 0x80d2, 0xf7 },
 434         { 0x80d3, 0xc2 },
 435         { 0x80d4, 0xdf },
 436         { 0x80d5, 0x02 },
 437         { 0x80d6, 0x9a },
 438         { 0x80d7, 0xd0 },
 439         { 0x8250, 0x0d },
 440         { 0x8251, 0xcd },
 441         { 0x8252, 0xe0 },
 442         { 0x8253, 0x05 },
 443         { 0x8254, 0xa7 },
 444         { 0x8255, 0xff },
 445         { 0x8256, 0xed },
 446         { 0x8257, 0x5b },
 447         { 0x8258, 0xae },
 448         { 0x8259, 0xe6 },
 449         { 0x825a, 0x3d },
 450         { 0x825b, 0x0f },
 451         { 0x825c, 0x0d },
 452         { 0x825d, 0xea },
 453         { 0x825e, 0xf2 },
 454         { 0x825f, 0x51 },
 455         { 0x8260, 0xf5 },
 456         { 0x8261, 0x06 },
 457         { 0x821a, 0x00 },
 458         { 0x8546, 0x40 },
 459         { 0x8210, 0x26 },
 460         { 0x8211, 0xf6 },
 461         { 0x8212, 0x84 },
 462         { 0x8213, 0x02 },
 463         { 0x8502, 0x01 },
 464         { 0x8121, 0x04 },
 465         { 0x8122, 0x04 },
 466         { 0x852e, 0x10 },
 467         { 0x80a4, 0xca },
 468         { 0x80a7, 0x40 },
 469         { 0x8526, 0x01 },
 470 };
 471
 472 static int au8522_enable_modulation(struct dvb_frontend *fe,
 473                                     fe_modulation_t m)
 474 {
 475         struct au8522_state *state = fe->demodulator_priv;
 476         int i;
 477
 478         dprintk("%s(0x%08x)\n", __func__, m);
 479
 480         switch (m) {
 481         case VSB_8:
 482                 dprintk("%s() VSB_8\n", __func__);
 483                 for (i = 0; i < ARRAY_SIZE(VSB_mod_tab); i++)
 484                         au8522_writereg(state,
 485                                 VSB_mod_tab[i].reg,
 486                                 VSB_mod_tab[i].data);
 487                 au8522_set_if(fe, state->config->vsb_if);
 488                 break;
 489         case QAM_64:
 490                 dprintk("%s() QAM 64\n", __func__);
 491                 for (i = 0; i < ARRAY_SIZE(QAM64_mod_tab); i++)
 492                         au8522_writereg(state,
 493                                 QAM64_mod_tab[i].reg,
 494                                 QAM64_mod_tab[i].data);
 495                 au8522_set_if(fe, state->config->qam_if);
 496                 break;
 497         case QAM_256:
 498                 dprintk("%s() QAM 256\n", __func__);
 499                 for (i = 0; i < ARRAY_SIZE(QAM256_mod_tab); i++)
 500                         au8522_writereg(state,
 501                                 QAM256_mod_tab[i].reg,
 502                                 QAM256_mod_tab[i].data);
 503                 au8522_set_if(fe, state->config->qam_if);
 504                 break;
 505         default:
 506                 dprintk("%s() Invalid modulation\n", __func__);
 507                 return -EINVAL;
 508         }
 509
 510         state->current_modulation = m;
 511
 512         return 0;
 513 }
 514
 515 /* Talk to the demod, set the FEC, GUARD, QAM settings etc */
 516 static int au8522_set_frontend(struct dvb_frontend *fe)
 517 {
 518         struct dtv_frontend_properties *c = &fe->dtv_property_cache;
 519         struct au8522_state *state = fe->demodulator_priv;
 520         int ret = -EINVAL;
 521
 522         dprintk("%s(frequency=%d)\n", __func__, c->frequency);
 523
 524         if ((state->current_frequency == c->frequency) &&
 525             (state->current_modulation == c->modulation))
 526                 return 0;
 527
 528         if (fe->ops.tuner_ops.set_params) {
 529                 if (fe->ops.i2c_gate_ctrl)
 530                         fe->ops.i2c_gate_ctrl(fe, 1);
 531                 ret = fe->ops.tuner_ops.set_params(fe);
 532                 if (fe->ops.i2c_gate_ctrl)
 533                         fe->ops.i2c_gate_ctrl(fe, 0);
 534         }
 535
 536         if (ret < 0)
 537                 return ret;
 538
 539         /* Allow the tuner to settle */
 540         msleep(100);
 541
 542         au8522_enable_modulation(fe, c->modulation);
 543
 544         state->current_frequency = c->frequency;
 545
 546         return 0;
 547 }
 548
 549 static int au8522_read_status(struct dvb_frontend *fe, fe_status_t *status)
 550 {
 551         struct au8522_state *state = fe->demodulator_priv;
 552         u8 reg;
 553         u32 tuner_status = 0;
 554
 555         *status = 0;
 556
 557         if (state->current_modulation == VSB_8) {
 558                 dprintk("%s() Checking VSB_8\n", __func__);
 559                 reg = au8522_readreg(state, 0x4088);
 560                 if ((reg & 0x03) == 0x03)
 561                         *status |= FE_HAS_LOCK | FE_HAS_SYNC | FE_HAS_VITERBI;
 562         } else {
 563                 dprintk("%s() Checking QAM\n", __func__);
 564                 reg = au8522_readreg(state, 0x4541);
 565                 if (reg & 0x80)
 566                         *status |= FE_HAS_VITERBI;
 567                 if (reg & 0x20)
 568                         *status |= FE_HAS_LOCK | FE_HAS_SYNC;
 569         }
 570
 571         switch (state->config->status_mode) {
 572         case AU8522_DEMODLOCKING:
 573                 dprintk("%s() DEMODLOCKING\n", __func__);
 574                 if (*status & FE_HAS_VITERBI)
 575                         *status |= FE_HAS_CARRIER | FE_HAS_SIGNAL;
 576                 break;
 577         case AU8522_TUNERLOCKING:
 578                 /* Get the tuner status */
 579                 dprintk("%s() TUNERLOCKING\n", __func__);
 580                 if (fe->ops.tuner_ops.get_status) {
 581                         if (fe->ops.i2c_gate_ctrl)
 582                                 fe->ops.i2c_gate_ctrl(fe, 1);
 583
 584                         fe->ops.tuner_ops.get_status(fe, &tuner_status);
 585
 586                         if (fe->ops.i2c_gate_ctrl)
 587                                 fe->ops.i2c_gate_ctrl(fe, 0);
 588                 }
 589                 if (tuner_status)
 590                         *status |= FE_HAS_CARRIER | FE_HAS_SIGNAL;
 591                 break;
 592         }
 593         state->fe_status = *status;
 594
 595         if (*status & FE_HAS_LOCK)
 596                 /* turn on LED, if it isn't on already */
 597                 au8522_led_ctrl(state, -1);
 598         else
 599                 /* turn off LED */
 600                 au8522_led_ctrl(state, 0);
 601
 602         dprintk("%s() status 0x%08x\n", __func__, *status);
 603
 604         return 0;
 605 }
 606
 607 static int au8522_led_status(struct au8522_state *state, const u16 *snr)
 608 {
 609         struct au8522_led_config *led_config = state->config->led_cfg;
 610         int led;
 611         u16 strong;
 612
 613         /* bail out if we can't control an LED */
 614         if (!led_config)
 615                 return 0;
 616
 617         if (0 == (state->fe_status & FE_HAS_LOCK))
 618                 return au8522_led_ctrl(state, 0);
 619         else if (state->current_modulation == QAM_256)
 620                 strong = led_config->qam256_strong;
 621         else if (state->current_modulation == QAM_64)
 622                 strong = led_config->qam64_strong;
 623         else /* (state->current_modulation == VSB_8) */
 624                 strong = led_config->vsb8_strong;
 625
 626         if (*snr >= strong)
 627                 led = 2;
 628         else
 629                 led = 1;
 630
 631         if ((state->led_state) &&
 632             (((strong < *snr) ? (*snr - strong) : (strong - *snr)) <= 10))
 633                 /* snr didn't change enough to bother
 634                  * changing the color of the led */
 635                 return 0;
 636
 637         return au8522_led_ctrl(state, led);
 638 }
 639
 640 static int au8522_read_snr(struct dvb_frontend *fe, u16 *snr)
 641 {
 642         struct au8522_state *state = fe->demodulator_priv;
 643         int ret = -EINVAL;
 644
 645         dprintk("%s()\n", __func__);
 646
 647         if (state->current_modulation == QAM_256)
 648                 ret = au8522_mse2snr_lookup(qam256_mse2snr_tab,
 649                                             ARRAY_SIZE(qam256_mse2snr_tab),
 650                                             au8522_readreg(state, 0x4522),
 651                                             snr);
 652         else if (state->current_modulation == QAM_64)
 653                 ret = au8522_mse2snr_lookup(qam64_mse2snr_tab,
 654                                             ARRAY_SIZE(qam64_mse2snr_tab),
 655                                             au8522_readreg(state, 0x4522),
 656                                             snr);
 657         else /* VSB_8 */
 658                 ret = au8522_mse2snr_lookup(vsb_mse2snr_tab,
 659                                             ARRAY_SIZE(vsb_mse2snr_tab),
 660                                             au8522_readreg(state, 0x4311),
 661                                             snr);
 662
 663         if (state->config->led_cfg)
 664                 au8522_led_status(state, snr);
 665
 666         return ret;
 667 }
 668
 669 static int au8522_read_signal_strength(struct dvb_frontend *fe,
 670                                        u16 *signal_strength)
 671 {
 672         /* borrowed from lgdt330x.c
 673          *
 674          * Calculate strength from SNR up to 35dB
 675          * Even though the SNR can go higher than 35dB,
 676          * there is some comfort factor in having a range of
 677          * strong signals that can show at 100%
 678          */
 679         u16 snr;
 680         u32 tmp;
 681         int ret = au8522_read_snr(fe, &snr);
 682
 683         *signal_strength = 0;
 684
 685         if (0 == ret) {
 686                 /* The following calculation method was chosen
 687                  * purely for the sake of code re-use from the
 688                  * other demod drivers that use this method */
 689
 690                 /* Convert from SNR in dB * 10 to 8.24 fixed-point */
 691                 tmp = (snr * ((1 << 24) / 10));
 692
 693                 /* Convert from 8.24 fixed-point to
 694                  * scale the range 0 - 35*2^24 into 0 - 65535*/
 695                 if (tmp >= 8960 * 0x10000)
 696                         *signal_strength = 0xffff;
 697                 else
 698                         *signal_strength = tmp / 8960;
 699         }
 700
 701         return ret;
 702 }
 703
 704 static int au8522_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
 705 {
 706         struct au8522_state *state = fe->demodulator_priv;
 707
 708         if (state->current_modulation == VSB_8)
 709                 *ucblocks = au8522_readreg(state, 0x4087);
 710         else
 711                 *ucblocks = au8522_readreg(state, 0x4543);
 712
 713         return 0;
 714 }
 715
 716 static int au8522_read_ber(struct dvb_frontend *fe, u32 *ber)
 717 {
 718         return au8522_read_ucblocks(fe, ber);
 719 }
 720
 721 static int au8522_get_frontend(struct dvb_frontend *fe)
 722 {
 723         struct dtv_frontend_properties *c = &fe->dtv_property_cache;
 724         struct au8522_state *state = fe->demodulator_priv;
 725
 726         c->frequency = state->current_frequency;
 727         c->modulation = state->current_modulation;
 728
 729         return 0;
 730 }
 731
 732 static int au8522_get_tune_settings(struct dvb_frontend *fe,
 733                                     struct dvb_frontend_tune_settings *tune)
 734 {
 735         tune->min_delay_ms = 1000;
 736         return 0;
 737 }
 738
 739 static struct dvb_frontend_ops au8522_ops;
 740
 741
 742 static void au8522_release(struct dvb_frontend *fe)
 743 {
 744         struct au8522_state *state = fe->demodulator_priv;
 745         au8522_release_state(state);
 746 }
 747
 748 struct dvb_frontend *au8522_attach(const struct au8522_config *config,
 749                                    struct i2c_adapter *i2c)
 750 {
 751         struct au8522_state *state = NULL;
 752         int instance;
 753
 754         /* allocate memory for the internal state */
 755         instance = au8522_get_state(&state, i2c, config->demod_address);
 756         switch (instance) {
 757         case 0:
 758                 dprintk("%s state allocation failed\n", __func__);
 759                 break;
 760         case 1:
 761                 /* new demod instance */
 762                 dprintk("%s using new instance\n", __func__);
 763                 break;
 764         default:
 765                 /* existing demod instance */
 766                 dprintk("%s using existing instance\n", __func__);
 767                 break;
 768         }
 769
 770         /* setup the state */
 771         state->config = config;
 772         state->i2c = i2c;
 773         state->operational_mode = AU8522_DIGITAL_MODE;
 774
 775         /* create dvb_frontend */
 776         memcpy(&state->frontend.ops, &au8522_ops,
 777                sizeof(struct dvb_frontend_ops));
 778         state->frontend.demodulator_priv = state;
 779
 780         state->frontend.ops.analog_ops.i2c_gate_ctrl = au8522_analog_i2c_gate_ctrl;
 781
 782         if (au8522_init(&state->frontend) != 0) {
 783                 printk(KERN_ERR "%s: Failed to initialize correctly\n",
 784                         __func__);
 785                 goto error;
 786         }
 787
 788         /* Note: Leaving the I2C gate open here. */
 789         au8522_i2c_gate_ctrl(&state->frontend, 1);
 790
 791         return &state->frontend;
 792
 793 error:
 794         au8522_release_state(state);
 795         return NULL;
 796 }
 797 EXPORT_SYMBOL(au8522_attach);
 798
 799 static struct dvb_frontend_ops au8522_ops = {
 800         .delsys = { SYS_ATSC, SYS_DVBC_ANNEX_B },
 801         .info = {
 802                 .name                   = "Auvitek AU8522 QAM/8VSB Frontend",
 803                 .frequency_min          = 54000000,
 804                 .frequency_max          = 858000000,
 805                 .frequency_stepsize     = 62500,
 806                 .caps = FE_CAN_QAM_64 | FE_CAN_QAM_256 | FE_CAN_8VSB
 807         },
 808
 809         .init                 = au8522_init,
 810         .sleep                = au8522_sleep,
 811         .i2c_gate_ctrl        = au8522_i2c_gate_ctrl,
 812         .set_frontend         = au8522_set_frontend,
 813         .get_frontend         = au8522_get_frontend,
 814         .get_tune_settings    = au8522_get_tune_settings,
 815         .read_status          = au8522_read_status,
 816         .read_ber             = au8522_read_ber,
 817         .read_signal_strength = au8522_read_signal_strength,
 818         .read_snr             = au8522_read_snr,
 819         .read_ucblocks        = au8522_read_ucblocks,
 820         .release              = au8522_release,
 821 };
 822
 823 module_param(debug, int, 0644);
 824 MODULE_PARM_DESC(debug, "Enable verbose debug messages");
 825
 826 MODULE_DESCRIPTION("Auvitek AU8522 QAM-B/ATSC Demodulator driver");
 827 MODULE_AUTHOR("Steven Toth");
 828 MODULE_LICENSE("GPL");