drivers/media/dvb-frontends/stv0297.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3     Driver for STV0297 demodulator
   4
   5     Copyright (C) 2004 Andrew de Quincey <adq_dvb@lidskialf.net>
   6     Copyright (C) 2003-2004 Dennis Noermann <dennis.noermann@noernet.de>
   7
   8 */
   9
  10 #include <linux/init.h>
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/string.h>
  14 #include <linux/delay.h>
  15 #include <linux/jiffies.h>
  16 #include <linux/slab.h>
  17
  18 #include <media/dvb_frontend.h>
  19 #include "stv0297.h"
  20
  21 struct stv0297_state {
  22         struct i2c_adapter *i2c;
  23         const struct stv0297_config *config;
  24         struct dvb_frontend frontend;
  25
  26         unsigned long last_ber;
  27         unsigned long base_freq;
  28 };
  29
  30 #if 1
  31 #define dprintk(x...) printk(x)
  32 #else
  33 #define dprintk(x...)
  34 #endif
  35
  36 #define STV0297_CLOCK_KHZ   28900
  37
  38
  39 static int stv0297_writereg(struct stv0297_state *state, u8 reg, u8 data)
  40 {
  41         int ret;
  42         u8 buf[] = { reg, data };
  43         struct i2c_msg msg = {.addr = state->config->demod_address,.flags = 0,.buf = buf,.len = 2 };
  44
  45         ret = i2c_transfer(state->i2c, &msg, 1);
  46
  47         if (ret != 1)
  48                 dprintk("%s: writereg error (reg == 0x%02x, val == 0x%02x, ret == %i)\n",
  49                         __func__, reg, data, ret);
  50
  51         return (ret != 1) ? -1 : 0;
  52 }
  53
  54 static int stv0297_readreg(struct stv0297_state *state, u8 reg)
  55 {
  56         int ret;
  57         u8 b0[] = { reg };
  58         u8 b1[] = { 0 };
  59         struct i2c_msg msg[] = { {.addr = state->config->demod_address,.flags = 0,.buf = b0,.len = 1},
  60                                  {.addr = state->config->demod_address,.flags = I2C_M_RD,.buf = b1,.len = 1}
  61                                };
  62
  63         // this device needs a STOP between the register and data
  64         if (state->config->stop_during_read) {
  65                 if ((ret = i2c_transfer(state->i2c, &msg[0], 1)) != 1) {
  66                         dprintk("%s: readreg error (reg == 0x%02x, ret == %i)\n", __func__, reg, ret);
  67                         return -1;
  68                 }
  69                 if ((ret = i2c_transfer(state->i2c, &msg[1], 1)) != 1) {
  70                         dprintk("%s: readreg error (reg == 0x%02x, ret == %i)\n", __func__, reg, ret);
  71                         return -1;
  72                 }
  73         } else {
  74                 if ((ret = i2c_transfer(state->i2c, msg, 2)) != 2) {
  75                         dprintk("%s: readreg error (reg == 0x%02x, ret == %i)\n", __func__, reg, ret);
  76                         return -1;
  77                 }
  78         }
  79
  80         return b1[0];
  81 }
  82
  83 static int stv0297_writereg_mask(struct stv0297_state *state, u8 reg, u8 mask, u8 data)
  84 {
  85         int val;
  86
  87         val = stv0297_readreg(state, reg);
  88         val &= ~mask;
  89         val |= (data & mask);
  90         stv0297_writereg(state, reg, val);
  91
  92         return 0;
  93 }
  94
  95 static int stv0297_readregs(struct stv0297_state *state, u8 reg1, u8 * b, u8 len)
  96 {
  97         int ret;
  98         struct i2c_msg msg[] = { {.addr = state->config->demod_address,.flags = 0,.buf =
  99                                   &reg1,.len = 1},
 100         {.addr = state->config->demod_address,.flags = I2C_M_RD,.buf = b,.len = len}
 101         };
 102
 103         // this device needs a STOP between the register and data
 104         if (state->config->stop_during_read) {
 105                 if ((ret = i2c_transfer(state->i2c, &msg[0], 1)) != 1) {
 106                         dprintk("%s: readreg error (reg == 0x%02x, ret == %i)\n", __func__, reg1, ret);
 107                         return -1;
 108                 }
 109                 if ((ret = i2c_transfer(state->i2c, &msg[1], 1)) != 1) {
 110                         dprintk("%s: readreg error (reg == 0x%02x, ret == %i)\n", __func__, reg1, ret);
 111                         return -1;
 112                 }
 113         } else {
 114                 if ((ret = i2c_transfer(state->i2c, msg, 2)) != 2) {
 115                         dprintk("%s: readreg error (reg == 0x%02x, ret == %i)\n", __func__, reg1, ret);
 116                         return -1;
 117                 }
 118         }
 119
 120         return 0;
 121 }
 122
 123 static u32 stv0297_get_symbolrate(struct stv0297_state *state)
 124 {
 125         u64 tmp;
 126
 127         tmp = (u64)(stv0297_readreg(state, 0x55)
 128                     | (stv0297_readreg(state, 0x56) << 8)
 129                     | (stv0297_readreg(state, 0x57) << 16)
 130                     | (stv0297_readreg(state, 0x58) << 24));
 131
 132         tmp *= STV0297_CLOCK_KHZ;
 133         tmp >>= 32;
 134
 135         return (u32) tmp;
 136 }
 137
 138 static void stv0297_set_symbolrate(struct stv0297_state *state, u32 srate)
 139 {
 140         long tmp;
 141
 142         tmp = 131072L * srate;  /* 131072 = 2^17  */
 143         tmp = tmp / (STV0297_CLOCK_KHZ / 4);    /* 1/4 = 2^-2 */
 144         tmp = tmp * 8192L;      /* 8192 = 2^13 */
 145
 146         stv0297_writereg(state, 0x55, (unsigned char) (tmp & 0xFF));
 147         stv0297_writereg(state, 0x56, (unsigned char) (tmp >> 8));
 148         stv0297_writereg(state, 0x57, (unsigned char) (tmp >> 16));
 149         stv0297_writereg(state, 0x58, (unsigned char) (tmp >> 24));
 150 }
 151
 152 static void stv0297_set_sweeprate(struct stv0297_state *state, short fshift, long symrate)
 153 {
 154         long tmp;
 155
 156         tmp = (long) fshift *262144L;   /* 262144 = 2*18 */
 157         tmp /= symrate;
 158         tmp *= 1024;            /* 1024 = 2*10   */
 159
 160         // adjust
 161         if (tmp >= 0) {
 162                 tmp += 500000;
 163         } else {
 164                 tmp -= 500000;
 165         }
 166         tmp /= 1000000;
 167
 168         stv0297_writereg(state, 0x60, tmp & 0xFF);
 169         stv0297_writereg_mask(state, 0x69, 0xF0, (tmp >> 4) & 0xf0);
 170 }
 171
 172 static void stv0297_set_carrieroffset(struct stv0297_state *state, long offset)
 173 {
 174         long tmp;
 175
 176         /* symrate is hardcoded to 10000 */
 177         tmp = offset * 26844L;  /* (2**28)/10000 */
 178         if (tmp < 0)
 179                 tmp += 0x10000000;
 180         tmp &= 0x0FFFFFFF;
 181
 182         stv0297_writereg(state, 0x66, (unsigned char) (tmp & 0xFF));
 183         stv0297_writereg(state, 0x67, (unsigned char) (tmp >> 8));
 184         stv0297_writereg(state, 0x68, (unsigned char) (tmp >> 16));
 185         stv0297_writereg_mask(state, 0x69, 0x0F, (tmp >> 24) & 0x0f);
 186 }
 187
 188 /*
 189 static long stv0297_get_carrieroffset(struct stv0297_state *state)
 190 {
 191         s64 tmp;
 192
 193         stv0297_writereg(state, 0x6B, 0x00);
 194
 195         tmp = stv0297_readreg(state, 0x66);
 196         tmp |= (stv0297_readreg(state, 0x67) << 8);
 197         tmp |= (stv0297_readreg(state, 0x68) << 16);
 198         tmp |= (stv0297_readreg(state, 0x69) & 0x0F) << 24;
 199
 200         tmp *= stv0297_get_symbolrate(state);
 201         tmp >>= 28;
 202
 203         return (s32) tmp;
 204 }
 205 */
 206
 207 static void stv0297_set_initialdemodfreq(struct stv0297_state *state, long freq)
 208 {
 209         s32 tmp;
 210
 211         if (freq > 10000)
 212                 freq -= STV0297_CLOCK_KHZ;
 213
 214         tmp = (STV0297_CLOCK_KHZ * 1000) / (1 << 16);
 215         tmp = (freq * 1000) / tmp;
 216         if (tmp > 0xffff)
 217                 tmp = 0xffff;
 218
 219         stv0297_writereg_mask(state, 0x25, 0x80, 0x80);
 220         stv0297_writereg(state, 0x21, tmp >> 8);
 221         stv0297_writereg(state, 0x20, tmp);
 222 }
 223
 224 static int stv0297_set_qam(struct stv0297_state *state,
 225                            enum fe_modulation modulation)
 226 {
 227         int val = 0;
 228
 229         switch (modulation) {
 230         case QAM_16:
 231                 val = 0;
 232                 break;
 233
 234         case QAM_32:
 235                 val = 1;
 236                 break;
 237
 238         case QAM_64:
 239                 val = 4;
 240                 break;
 241
 242         case QAM_128:
 243                 val = 2;
 244                 break;
 245
 246         case QAM_256:
 247                 val = 3;
 248                 break;
 249
 250         default:
 251                 return -EINVAL;
 252         }
 253
 254         stv0297_writereg_mask(state, 0x00, 0x70, val << 4);
 255
 256         return 0;
 257 }
 258
 259 static int stv0297_set_inversion(struct stv0297_state *state,
 260                                  enum fe_spectral_inversion inversion)
 261 {
 262         int val = 0;
 263
 264         switch (inversion) {
 265         case INVERSION_OFF:
 266                 val = 0;
 267                 break;
 268
 269         case INVERSION_ON:
 270                 val = 1;
 271                 break;
 272
 273         default:
 274                 return -EINVAL;
 275         }
 276
 277         stv0297_writereg_mask(state, 0x83, 0x08, val << 3);
 278
 279         return 0;
 280 }
 281
 282 static int stv0297_i2c_gate_ctrl(struct dvb_frontend *fe, int enable)
 283 {
 284         struct stv0297_state *state = fe->demodulator_priv;
 285
 286         if (enable) {
 287                 stv0297_writereg(state, 0x87, 0x78);
 288                 stv0297_writereg(state, 0x86, 0xc8);
 289         }
 290
 291         return 0;
 292 }
 293
 294 static int stv0297_init(struct dvb_frontend *fe)
 295 {
 296         struct stv0297_state *state = fe->demodulator_priv;
 297         int i;
 298
 299         /* load init table */
 300         for (i=0; !(state->config->inittab[i] == 0xff && state->config->inittab[i+1] == 0xff); i+=2)
 301                 stv0297_writereg(state, state->config->inittab[i], state->config->inittab[i+1]);
 302         msleep(200);
 303
 304         state->last_ber = 0;
 305
 306         return 0;
 307 }
 308
 309 static int stv0297_sleep(struct dvb_frontend *fe)
 310 {
 311         struct stv0297_state *state = fe->demodulator_priv;
 312
 313         stv0297_writereg_mask(state, 0x80, 1, 1);
 314
 315         return 0;
 316 }
 317
 318 static int stv0297_read_status(struct dvb_frontend *fe,
 319                                enum fe_status *status)
 320 {
 321         struct stv0297_state *state = fe->demodulator_priv;
 322
 323         u8 sync = stv0297_readreg(state, 0xDF);
 324
 325         *status = 0;
 326         if (sync & 0x80)
 327                 *status |=
 328                         FE_HAS_SYNC | FE_HAS_SIGNAL | FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_LOCK;
 329         return 0;
 330 }
 331
 332 static int stv0297_read_ber(struct dvb_frontend *fe, u32 * ber)
 333 {
 334         struct stv0297_state *state = fe->demodulator_priv;
 335         u8 BER[3];
 336
 337         stv0297_readregs(state, 0xA0, BER, 3);
 338         if (!(BER[0] & 0x80)) {
 339                 state->last_ber = BER[2] << 8 | BER[1];
 340                 stv0297_writereg_mask(state, 0xA0, 0x80, 0x80);
 341         }
 342
 343         *ber = state->last_ber;
 344
 345         return 0;
 346 }
 347
 348
 349 static int stv0297_read_signal_strength(struct dvb_frontend *fe, u16 * strength)
 350 {
 351         struct stv0297_state *state = fe->demodulator_priv;
 352         u8 STRENGTH[3];
 353         u16 tmp;
 354
 355         stv0297_readregs(state, 0x41, STRENGTH, 3);
 356         tmp = (STRENGTH[1] & 0x03) << 8 | STRENGTH[0];
 357         if (STRENGTH[2] & 0x20) {
 358                 if (tmp < 0x200)
 359                         tmp = 0;
 360                 else
 361                         tmp = tmp - 0x200;
 362         } else {
 363                 if (tmp > 0x1ff)
 364                         tmp = 0;
 365                 else
 366                         tmp = 0x1ff - tmp;
 367         }
 368         *strength = (tmp << 7) | (tmp >> 2);
 369         return 0;
 370 }
 371
 372 static int stv0297_read_snr(struct dvb_frontend *fe, u16 * snr)
 373 {
 374         struct stv0297_state *state = fe->demodulator_priv;
 375         u8 SNR[2];
 376
 377         stv0297_readregs(state, 0x07, SNR, 2);
 378         *snr = SNR[1] << 8 | SNR[0];
 379
 380         return 0;
 381 }
 382
 383 static int stv0297_read_ucblocks(struct dvb_frontend *fe, u32 * ucblocks)
 384 {
 385         struct stv0297_state *state = fe->demodulator_priv;
 386
 387         stv0297_writereg_mask(state, 0xDF, 0x03, 0x03); /* freeze the counters */
 388
 389         *ucblocks = (stv0297_readreg(state, 0xD5) << 8)
 390                 | stv0297_readreg(state, 0xD4);
 391
 392         stv0297_writereg_mask(state, 0xDF, 0x03, 0x02); /* clear the counters */
 393         stv0297_writereg_mask(state, 0xDF, 0x03, 0x01); /* re-enable the counters */
 394
 395         return 0;
 396 }
 397
 398 static int stv0297_set_frontend(struct dvb_frontend *fe)
 399 {
 400         struct dtv_frontend_properties *p = &fe->dtv_property_cache;
 401         struct stv0297_state *state = fe->demodulator_priv;
 402         int u_threshold;
 403         int initial_u;
 404         int blind_u;
 405         int delay;
 406         int sweeprate;
 407         int carrieroffset;
 408         unsigned long timeout;
 409         enum fe_spectral_inversion inversion;
 410
 411         switch (p->modulation) {
 412         case QAM_16:
 413         case QAM_32:
 414         case QAM_64:
 415                 delay = 100;
 416                 sweeprate = 1000;
 417                 break;
 418
 419         case QAM_128:
 420         case QAM_256:
 421                 delay = 200;
 422                 sweeprate = 500;
 423                 break;
 424
 425         default:
 426                 return -EINVAL;
 427         }
 428
 429         // determine inversion dependent parameters
 430         inversion = p->inversion;
 431         if (state->config->invert)
 432                 inversion = (inversion == INVERSION_ON) ? INVERSION_OFF : INVERSION_ON;
 433         carrieroffset = -330;
 434         switch (inversion) {
 435         case INVERSION_OFF:
 436                 break;
 437
 438         case INVERSION_ON:
 439                 sweeprate = -sweeprate;
 440                 carrieroffset = -carrieroffset;
 441                 break;
 442
 443         default:
 444                 return -EINVAL;
 445         }
 446
 447         stv0297_init(fe);
 448         if (fe->ops.tuner_ops.set_params) {
 449                 fe->ops.tuner_ops.set_params(fe);
 450                 if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
 451         }
 452
 453         /* clear software interrupts */
 454         stv0297_writereg(state, 0x82, 0x0);
 455
 456         /* set initial demodulation frequency */
 457         stv0297_set_initialdemodfreq(state, 7250);
 458
 459         /* setup AGC */
 460         stv0297_writereg_mask(state, 0x43, 0x10, 0x00);
 461         stv0297_writereg(state, 0x41, 0x00);
 462         stv0297_writereg_mask(state, 0x42, 0x03, 0x01);
 463         stv0297_writereg_mask(state, 0x36, 0x60, 0x00);
 464         stv0297_writereg_mask(state, 0x36, 0x18, 0x00);
 465         stv0297_writereg_mask(state, 0x71, 0x80, 0x80);
 466         stv0297_writereg(state, 0x72, 0x00);
 467         stv0297_writereg(state, 0x73, 0x00);
 468         stv0297_writereg_mask(state, 0x74, 0x0F, 0x00);
 469         stv0297_writereg_mask(state, 0x43, 0x08, 0x00);
 470         stv0297_writereg_mask(state, 0x71, 0x80, 0x00);
 471
 472         /* setup STL */
 473         stv0297_writereg_mask(state, 0x5a, 0x20, 0x20);
 474         stv0297_writereg_mask(state, 0x5b, 0x02, 0x02);
 475         stv0297_writereg_mask(state, 0x5b, 0x02, 0x00);
 476         stv0297_writereg_mask(state, 0x5b, 0x01, 0x00);
 477         stv0297_writereg_mask(state, 0x5a, 0x40, 0x40);
 478
 479         /* disable frequency sweep */
 480         stv0297_writereg_mask(state, 0x6a, 0x01, 0x00);
 481
 482         /* reset deinterleaver */
 483         stv0297_writereg_mask(state, 0x81, 0x01, 0x01);
 484         stv0297_writereg_mask(state, 0x81, 0x01, 0x00);
 485
 486         /* ??? */
 487         stv0297_writereg_mask(state, 0x83, 0x20, 0x20);
 488         stv0297_writereg_mask(state, 0x83, 0x20, 0x00);
 489
 490         /* reset equaliser */
 491         u_threshold = stv0297_readreg(state, 0x00) & 0xf;
 492         initial_u = stv0297_readreg(state, 0x01) >> 4;
 493         blind_u = stv0297_readreg(state, 0x01) & 0xf;
 494         stv0297_writereg_mask(state, 0x84, 0x01, 0x01);
 495         stv0297_writereg_mask(state, 0x84, 0x01, 0x00);
 496         stv0297_writereg_mask(state, 0x00, 0x0f, u_threshold);
 497         stv0297_writereg_mask(state, 0x01, 0xf0, initial_u << 4);
 498         stv0297_writereg_mask(state, 0x01, 0x0f, blind_u);
 499
 500         /* data comes from internal A/D */
 501         stv0297_writereg_mask(state, 0x87, 0x80, 0x00);
 502
 503         /* clear phase registers */
 504         stv0297_writereg(state, 0x63, 0x00);
 505         stv0297_writereg(state, 0x64, 0x00);
 506         stv0297_writereg(state, 0x65, 0x00);
 507         stv0297_writereg(state, 0x66, 0x00);
 508         stv0297_writereg(state, 0x67, 0x00);
 509         stv0297_writereg(state, 0x68, 0x00);
 510         stv0297_writereg_mask(state, 0x69, 0x0f, 0x00);
 511
 512         /* set parameters */
 513         stv0297_set_qam(state, p->modulation);
 514         stv0297_set_symbolrate(state, p->symbol_rate / 1000);
 515         stv0297_set_sweeprate(state, sweeprate, p->symbol_rate / 1000);
 516         stv0297_set_carrieroffset(state, carrieroffset);
 517         stv0297_set_inversion(state, inversion);
 518
 519         /* kick off lock */
 520         /* Disable corner detection for higher QAMs */
 521         if (p->modulation == QAM_128 ||
 522                 p->modulation == QAM_256)
 523                 stv0297_writereg_mask(state, 0x88, 0x08, 0x00);
 524         else
 525                 stv0297_writereg_mask(state, 0x88, 0x08, 0x08);
 526
 527         stv0297_writereg_mask(state, 0x5a, 0x20, 0x00);
 528         stv0297_writereg_mask(state, 0x6a, 0x01, 0x01);
 529         stv0297_writereg_mask(state, 0x43, 0x40, 0x40);
 530         stv0297_writereg_mask(state, 0x5b, 0x30, 0x00);
 531         stv0297_writereg_mask(state, 0x03, 0x0c, 0x0c);
 532         stv0297_writereg_mask(state, 0x03, 0x03, 0x03);
 533         stv0297_writereg_mask(state, 0x43, 0x10, 0x10);
 534
 535         /* wait for WGAGC lock */
 536         timeout = jiffies + msecs_to_jiffies(2000);
 537         while (time_before(jiffies, timeout)) {
 538                 msleep(10);
 539                 if (stv0297_readreg(state, 0x43) & 0x08)
 540                         break;
 541         }
 542         if (time_after(jiffies, timeout)) {
 543                 goto timeout;
 544         }
 545         msleep(20);
 546
 547         /* wait for equaliser partial convergence */
 548         timeout = jiffies + msecs_to_jiffies(500);
 549         while (time_before(jiffies, timeout)) {
 550                 msleep(10);
 551
 552                 if (stv0297_readreg(state, 0x82) & 0x04) {
 553                         break;
 554                 }
 555         }
 556         if (time_after(jiffies, timeout)) {
 557                 goto timeout;
 558         }
 559
 560         /* wait for equaliser full convergence */
 561         timeout = jiffies + msecs_to_jiffies(delay);
 562         while (time_before(jiffies, timeout)) {
 563                 msleep(10);
 564
 565                 if (stv0297_readreg(state, 0x82) & 0x08) {
 566                         break;
 567                 }
 568         }
 569         if (time_after(jiffies, timeout)) {
 570                 goto timeout;
 571         }
 572
 573         /* disable sweep */
 574         stv0297_writereg_mask(state, 0x6a, 1, 0);
 575         stv0297_writereg_mask(state, 0x88, 8, 0);
 576
 577         /* wait for main lock */
 578         timeout = jiffies + msecs_to_jiffies(20);
 579         while (time_before(jiffies, timeout)) {
 580                 msleep(10);
 581
 582                 if (stv0297_readreg(state, 0xDF) & 0x80) {
 583                         break;
 584                 }
 585         }
 586         if (time_after(jiffies, timeout)) {
 587                 goto timeout;
 588         }
 589         msleep(100);
 590
 591         /* is it still locked after that delay? */
 592         if (!(stv0297_readreg(state, 0xDF) & 0x80)) {
 593                 goto timeout;
 594         }
 595
 596         /* success!! */
 597         stv0297_writereg_mask(state, 0x5a, 0x40, 0x00);
 598         state->base_freq = p->frequency;
 599         return 0;
 600
 601 timeout:
 602         stv0297_writereg_mask(state, 0x6a, 0x01, 0x00);
 603         return 0;
 604 }
 605
 606 static int stv0297_get_frontend(struct dvb_frontend *fe,
 607                                 struct dtv_frontend_properties *p)
 608 {
 609         struct stv0297_state *state = fe->demodulator_priv;
 610         int reg_00, reg_83;
 611
 612         reg_00 = stv0297_readreg(state, 0x00);
 613         reg_83 = stv0297_readreg(state, 0x83);
 614
 615         p->frequency = state->base_freq;
 616         p->inversion = (reg_83 & 0x08) ? INVERSION_ON : INVERSION_OFF;
 617         if (state->config->invert)
 618                 p->inversion = (p->inversion == INVERSION_ON) ? INVERSION_OFF : INVERSION_ON;
 619         p->symbol_rate = stv0297_get_symbolrate(state) * 1000;
 620         p->fec_inner = FEC_NONE;
 621
 622         switch ((reg_00 >> 4) & 0x7) {
 623         case 0:
 624                 p->modulation = QAM_16;
 625                 break;
 626         case 1:
 627                 p->modulation = QAM_32;
 628                 break;
 629         case 2:
 630                 p->modulation = QAM_128;
 631                 break;
 632         case 3:
 633                 p->modulation = QAM_256;
 634                 break;
 635         case 4:
 636                 p->modulation = QAM_64;
 637                 break;
 638         }
 639
 640         return 0;
 641 }
 642
 643 static void stv0297_release(struct dvb_frontend *fe)
 644 {
 645         struct stv0297_state *state = fe->demodulator_priv;
 646         kfree(state);
 647 }
 648
 649 static const struct dvb_frontend_ops stv0297_ops;
 650
 651 struct dvb_frontend *stv0297_attach(const struct stv0297_config *config,
 652                                     struct i2c_adapter *i2c)
 653 {
 654         struct stv0297_state *state = NULL;
 655
 656         /* allocate memory for the internal state */
 657         state = kzalloc(sizeof(struct stv0297_state), GFP_KERNEL);
 658         if (state == NULL)
 659                 goto error;
 660
 661         /* setup the state */
 662         state->config = config;
 663         state->i2c = i2c;
 664         state->last_ber = 0;
 665         state->base_freq = 0;
 666
 667         /* check if the demod is there */
 668         if ((stv0297_readreg(state, 0x80) & 0x70) != 0x20)
 669                 goto error;
 670
 671         /* create dvb_frontend */
 672         memcpy(&state->frontend.ops, &stv0297_ops, sizeof(struct dvb_frontend_ops));
 673         state->frontend.demodulator_priv = state;
 674         return &state->frontend;
 675
 676 error:
 677         kfree(state);
 678         return NULL;
 679 }
 680
 681 static const struct dvb_frontend_ops stv0297_ops = {
 682         .delsys = { SYS_DVBC_ANNEX_A },
 683         .info = {
 684                  .name = "ST STV0297 DVB-C",
 685                  .frequency_min_hz = 47 * MHz,
 686                  .frequency_max_hz = 862 * MHz,
 687                  .frequency_stepsize_hz = 62500,
 688                  .symbol_rate_min = 870000,
 689                  .symbol_rate_max = 11700000,
 690                  .caps = FE_CAN_QAM_16 | FE_CAN_QAM_32 | FE_CAN_QAM_64 |
 691                  FE_CAN_QAM_128 | FE_CAN_QAM_256 | FE_CAN_FEC_AUTO},
 692
 693         .release = stv0297_release,
 694
 695         .init = stv0297_init,
 696         .sleep = stv0297_sleep,
 697         .i2c_gate_ctrl = stv0297_i2c_gate_ctrl,
 698
 699         .set_frontend = stv0297_set_frontend,
 700         .get_frontend = stv0297_get_frontend,
 701
 702         .read_status = stv0297_read_status,
 703         .read_ber = stv0297_read_ber,
 704         .read_signal_strength = stv0297_read_signal_strength,
 705         .read_snr = stv0297_read_snr,
 706         .read_ucblocks = stv0297_read_ucblocks,
 707 };
 708
 709 MODULE_DESCRIPTION("ST STV0297 DVB-C Demodulator driver");
 710 MODULE_AUTHOR("Dennis Noermann and Andrew de Quincey");
 711 MODULE_LICENSE("GPL");
 712
 713 EXPORT_SYMBOL(stv0297_attach);