drivers/media/dvb/frontends/nxt6000.c

   1 /*
   2         NxtWave Communications - NXT6000 demodulator driver
   3
   4     Copyright (C) 2002-2003 Florian Schirmer <jolt@tuxbox.org>
   5     Copyright (C) 2003 Paul Andreassen <paul@andreassen.com.au>
   6
   7     This program is free software; you can redistribute it and/or modify
   8     it under the terms of the GNU General Public License as published by
   9     the Free Software Foundation; either version 2 of the License, or
  10     (at your option) any later version.
  11
  12     This program is distributed in the hope that it will be useful,
  13     but WITHOUT ANY WARRANTY; without even the implied warranty of
  14     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15     GNU General Public License for more details.
  16
  17     You should have received a copy of the GNU General Public License
  18     along with this program; if not, write to the Free Software
  19     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include <linux/init.h>
  23 #include <linux/kernel.h>
  24 #include <linux/module.h>
  25 #include <linux/string.h>
  26 #include <linux/slab.h>
  27
  28 #include "dvb_frontend.h"
  29 #include "nxt6000_priv.h"
  30 #include "nxt6000.h"
  31
  32
  33
  34 struct nxt6000_state {
  35         struct i2c_adapter* i2c;
  36         /* configuration settings */
  37         const struct nxt6000_config* config;
  38         struct dvb_frontend frontend;
  39 };
  40
  41 static int debug;
  42 #define dprintk if (debug) printk
  43
  44 static int nxt6000_writereg(struct nxt6000_state* state, u8 reg, u8 data)
  45 {
  46         u8 buf[] = { reg, data };
  47         struct i2c_msg msg = {.addr = state->config->demod_address,.flags = 0,.buf = buf,.len = 2 };
  48         int ret;
  49
  50         if ((ret = i2c_transfer(state->i2c, &msg, 1)) != 1)
  51                 dprintk("nxt6000: nxt6000_write error (reg: 0x%02X, data: 0x%02X, ret: %d)\n", reg, data, ret);
  52
  53         return (ret != 1) ? -EFAULT : 0;
  54 }
  55
  56 static u8 nxt6000_readreg(struct nxt6000_state* state, u8 reg)
  57 {
  58         int ret;
  59         u8 b0[] = { reg };
  60         u8 b1[] = { 0 };
  61         struct i2c_msg msgs[] = {
  62                 {.addr = state->config->demod_address,.flags = 0,.buf = b0,.len = 1},
  63                 {.addr = state->config->demod_address,.flags = I2C_M_RD,.buf = b1,.len = 1}
  64         };
  65
  66         ret = i2c_transfer(state->i2c, msgs, 2);
  67
  68         if (ret != 2)
  69                 dprintk("nxt6000: nxt6000_read error (reg: 0x%02X, ret: %d)\n", reg, ret);
  70
  71         return b1[0];
  72 }
  73
  74 static void nxt6000_reset(struct nxt6000_state* state)
  75 {
  76         u8 val;
  77
  78         val = nxt6000_readreg(state, OFDM_COR_CTL);
  79
  80         nxt6000_writereg(state, OFDM_COR_CTL, val & ~COREACT);
  81         nxt6000_writereg(state, OFDM_COR_CTL, val | COREACT);
  82 }
  83
  84 static int nxt6000_set_bandwidth(struct nxt6000_state* state, fe_bandwidth_t bandwidth)
  85 {
  86         u16 nominal_rate;
  87         int result;
  88
  89         switch (bandwidth) {
  90
  91         case BANDWIDTH_6_MHZ:
  92                 nominal_rate = 0x55B7;
  93                 break;
  94
  95         case BANDWIDTH_7_MHZ:
  96                 nominal_rate = 0x6400;
  97                 break;
  98
  99         case BANDWIDTH_8_MHZ:
 100                 nominal_rate = 0x7249;
 101                 break;
 102
 103         default:
 104                 return -EINVAL;
 105         }
 106
 107         if ((result = nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_1, nominal_rate & 0xFF)) < 0)
 108                 return result;
 109
 110         return nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_2, (nominal_rate >> 8) & 0xFF);
 111 }
 112
 113 static int nxt6000_set_guard_interval(struct nxt6000_state* state, fe_guard_interval_t guard_interval)
 114 {
 115         switch (guard_interval) {
 116
 117         case GUARD_INTERVAL_1_32:
 118                 return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x00 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));
 119
 120         case GUARD_INTERVAL_1_16:
 121                 return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x01 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));
 122
 123         case GUARD_INTERVAL_AUTO:
 124         case GUARD_INTERVAL_1_8:
 125                 return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x02 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));
 126
 127         case GUARD_INTERVAL_1_4:
 128                 return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x03 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));
 129
 130         default:
 131                 return -EINVAL;
 132         }
 133 }
 134
 135 static int nxt6000_set_inversion(struct nxt6000_state* state, fe_spectral_inversion_t inversion)
 136 {
 137         switch (inversion) {
 138
 139         case INVERSION_OFF:
 140                 return nxt6000_writereg(state, OFDM_ITB_CTL, 0x00);
 141
 142         case INVERSION_ON:
 143                 return nxt6000_writereg(state, OFDM_ITB_CTL, ITBINV);
 144
 145         default:
 146                 return -EINVAL;
 147
 148         }
 149 }
 150
 151 static int nxt6000_set_transmission_mode(struct nxt6000_state* state, fe_transmit_mode_t transmission_mode)
 152 {
 153         int result;
 154
 155         switch (transmission_mode) {
 156
 157         case TRANSMISSION_MODE_2K:
 158                 if ((result = nxt6000_writereg(state, EN_DMD_RACQ, 0x00 | (nxt6000_readreg(state, EN_DMD_RACQ) & ~0x03))) < 0)
 159                         return result;
 160
 161                 return nxt6000_writereg(state, OFDM_COR_MODEGUARD, (0x00 << 2) | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x04));
 162
 163         case TRANSMISSION_MODE_8K:
 164         case TRANSMISSION_MODE_AUTO:
 165                 if ((result = nxt6000_writereg(state, EN_DMD_RACQ, 0x02 | (nxt6000_readreg(state, EN_DMD_RACQ) & ~0x03))) < 0)
 166                         return result;
 167
 168                 return nxt6000_writereg(state, OFDM_COR_MODEGUARD, (0x01 << 2) | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x04));
 169
 170         default:
 171                 return -EINVAL;
 172
 173         }
 174 }
 175
 176 static void nxt6000_setup(struct dvb_frontend* fe)
 177 {
 178         struct nxt6000_state* state = fe->demodulator_priv;
 179
 180         nxt6000_writereg(state, RS_COR_SYNC_PARAM, SYNC_PARAM);
 181         nxt6000_writereg(state, BER_CTRL, /*(1 << 2) | */ (0x01 << 1) | 0x01);
 182         nxt6000_writereg(state, VIT_BERTIME_2, 0x00);  // BER Timer = 0x000200 * 256 = 131072 bits
 183         nxt6000_writereg(state, VIT_BERTIME_1, 0x02);  //
 184         nxt6000_writereg(state, VIT_BERTIME_0, 0x00);  //
 185         nxt6000_writereg(state, VIT_COR_INTEN, 0x98); // Enable BER interrupts
 186         nxt6000_writereg(state, VIT_COR_CTL, 0x82);   // Enable BER measurement
 187         nxt6000_writereg(state, VIT_COR_CTL, VIT_COR_RESYNC | 0x02 );
 188         nxt6000_writereg(state, OFDM_COR_CTL, (0x01 << 5) | (nxt6000_readreg(state, OFDM_COR_CTL) & 0x0F));
 189         nxt6000_writereg(state, OFDM_COR_MODEGUARD, FORCEMODE8K | 0x02);
 190         nxt6000_writereg(state, OFDM_AGC_CTL, AGCLAST | INITIAL_AGC_BW);
 191         nxt6000_writereg(state, OFDM_ITB_FREQ_1, 0x06);
 192         nxt6000_writereg(state, OFDM_ITB_FREQ_2, 0x31);
 193         nxt6000_writereg(state, OFDM_CAS_CTL, (0x01 << 7) | (0x02 << 3) | 0x04);
 194         nxt6000_writereg(state, CAS_FREQ, 0xBB);        /* CHECKME */
 195         nxt6000_writereg(state, OFDM_SYR_CTL, 1 << 2);
 196         nxt6000_writereg(state, OFDM_PPM_CTL_1, PPM256);
 197         nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_1, 0x49);
 198         nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_2, 0x72);
 199         nxt6000_writereg(state, ANALOG_CONTROL_0, 1 << 5);
 200         nxt6000_writereg(state, EN_DMD_RACQ, (1 << 7) | (3 << 4) | 2);
 201         nxt6000_writereg(state, DIAG_CONFIG, TB_SET);
 202
 203         if (state->config->clock_inversion)
 204                 nxt6000_writereg(state, SUB_DIAG_MODE_SEL, CLKINVERSION);
 205         else
 206                 nxt6000_writereg(state, SUB_DIAG_MODE_SEL, 0);
 207
 208         nxt6000_writereg(state, TS_FORMAT, 0);
 209 }
 210
 211 static void nxt6000_dump_status(struct nxt6000_state *state)
 212 {
 213         u8 val;
 214
 215 /*
 216         printk("RS_COR_STAT: 0x%02X\n", nxt6000_readreg(fe, RS_COR_STAT));
 217         printk("VIT_SYNC_STATUS: 0x%02X\n", nxt6000_readreg(fe, VIT_SYNC_STATUS));
 218         printk("OFDM_COR_STAT: 0x%02X\n", nxt6000_readreg(fe, OFDM_COR_STAT));
 219         printk("OFDM_SYR_STAT: 0x%02X\n", nxt6000_readreg(fe, OFDM_SYR_STAT));
 220         printk("OFDM_TPS_RCVD_1: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_1));
 221         printk("OFDM_TPS_RCVD_2: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_2));
 222         printk("OFDM_TPS_RCVD_3: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_3));
 223         printk("OFDM_TPS_RCVD_4: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_4));
 224         printk("OFDM_TPS_RESERVED_1: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RESERVED_1));
 225         printk("OFDM_TPS_RESERVED_2: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RESERVED_2));
 226 */
 227         printk("NXT6000 status:");
 228
 229         val = nxt6000_readreg(state, RS_COR_STAT);
 230
 231         printk(" DATA DESCR LOCK: %d,", val & 0x01);
 232         printk(" DATA SYNC LOCK: %d,", (val >> 1) & 0x01);
 233
 234         val = nxt6000_readreg(state, VIT_SYNC_STATUS);
 235
 236         printk(" VITERBI LOCK: %d,", (val >> 7) & 0x01);
 237
 238         switch ((val >> 4) & 0x07) {
 239
 240         case 0x00:
 241                 printk(" VITERBI CODERATE: 1/2,");
 242                 break;
 243
 244         case 0x01:
 245                 printk(" VITERBI CODERATE: 2/3,");
 246                 break;
 247
 248         case 0x02:
 249                 printk(" VITERBI CODERATE: 3/4,");
 250                 break;
 251
 252         case 0x03:
 253                 printk(" VITERBI CODERATE: 5/6,");
 254                 break;
 255
 256         case 0x04:
 257                 printk(" VITERBI CODERATE: 7/8,");
 258                 break;
 259
 260         default:
 261                 printk(" VITERBI CODERATE: Reserved,");
 262
 263         }
 264
 265         val = nxt6000_readreg(state, OFDM_COR_STAT);
 266
 267         printk(" CHCTrack: %d,", (val >> 7) & 0x01);
 268         printk(" TPSLock: %d,", (val >> 6) & 0x01);
 269         printk(" SYRLock: %d,", (val >> 5) & 0x01);
 270         printk(" AGCLock: %d,", (val >> 4) & 0x01);
 271
 272         switch (val & 0x0F) {
 273
 274         case 0x00:
 275                 printk(" CoreState: IDLE,");
 276                 break;
 277
 278         case 0x02:
 279                 printk(" CoreState: WAIT_AGC,");
 280                 break;
 281
 282         case 0x03:
 283                 printk(" CoreState: WAIT_SYR,");
 284                 break;
 285
 286         case 0x04:
 287                 printk(" CoreState: WAIT_PPM,");
 288                 break;
 289
 290         case 0x01:
 291                 printk(" CoreState: WAIT_TRL,");
 292                 break;
 293
 294         case 0x05:
 295                 printk(" CoreState: WAIT_TPS,");
 296                 break;
 297
 298         case 0x06:
 299                 printk(" CoreState: MONITOR_TPS,");
 300                 break;
 301
 302         default:
 303                 printk(" CoreState: Reserved,");
 304
 305         }
 306
 307         val = nxt6000_readreg(state, OFDM_SYR_STAT);
 308
 309         printk(" SYRLock: %d,", (val >> 4) & 0x01);
 310         printk(" SYRMode: %s,", (val >> 2) & 0x01 ? "8K" : "2K");
 311
 312         switch ((val >> 4) & 0x03) {
 313
 314         case 0x00:
 315                 printk(" SYRGuard: 1/32,");
 316                 break;
 317
 318         case 0x01:
 319                 printk(" SYRGuard: 1/16,");
 320                 break;
 321
 322         case 0x02:
 323                 printk(" SYRGuard: 1/8,");
 324                 break;
 325
 326         case 0x03:
 327                 printk(" SYRGuard: 1/4,");
 328                 break;
 329         }
 330
 331         val = nxt6000_readreg(state, OFDM_TPS_RCVD_3);
 332
 333         switch ((val >> 4) & 0x07) {
 334
 335         case 0x00:
 336                 printk(" TPSLP: 1/2,");
 337                 break;
 338
 339         case 0x01:
 340                 printk(" TPSLP: 2/3,");
 341                 break;
 342
 343         case 0x02:
 344                 printk(" TPSLP: 3/4,");
 345                 break;
 346
 347         case 0x03:
 348                 printk(" TPSLP: 5/6,");
 349                 break;
 350
 351         case 0x04:
 352                 printk(" TPSLP: 7/8,");
 353                 break;
 354
 355         default:
 356                 printk(" TPSLP: Reserved,");
 357
 358         }
 359
 360         switch (val & 0x07) {
 361
 362         case 0x00:
 363                 printk(" TPSHP: 1/2,");
 364                 break;
 365
 366         case 0x01:
 367                 printk(" TPSHP: 2/3,");
 368                 break;
 369
 370         case 0x02:
 371                 printk(" TPSHP: 3/4,");
 372                 break;
 373
 374         case 0x03:
 375                 printk(" TPSHP: 5/6,");
 376                 break;
 377
 378         case 0x04:
 379                 printk(" TPSHP: 7/8,");
 380                 break;
 381
 382         default:
 383                 printk(" TPSHP: Reserved,");
 384
 385         }
 386
 387         val = nxt6000_readreg(state, OFDM_TPS_RCVD_4);
 388
 389         printk(" TPSMode: %s,", val & 0x01 ? "8K" : "2K");
 390
 391         switch ((val >> 4) & 0x03) {
 392
 393         case 0x00:
 394                 printk(" TPSGuard: 1/32,");
 395                 break;
 396
 397         case 0x01:
 398                 printk(" TPSGuard: 1/16,");
 399                 break;
 400
 401         case 0x02:
 402                 printk(" TPSGuard: 1/8,");
 403                 break;
 404
 405         case 0x03:
 406                 printk(" TPSGuard: 1/4,");
 407                 break;
 408
 409         }
 410
 411         /* Strange magic required to gain access to RF_AGC_STATUS */
 412         nxt6000_readreg(state, RF_AGC_VAL_1);
 413         val = nxt6000_readreg(state, RF_AGC_STATUS);
 414         val = nxt6000_readreg(state, RF_AGC_STATUS);
 415
 416         printk(" RF AGC LOCK: %d,", (val >> 4) & 0x01);
 417         printk("\n");
 418 }
 419
 420 static int nxt6000_read_status(struct dvb_frontend* fe, fe_status_t* status)
 421 {
 422         u8 core_status;
 423         struct nxt6000_state* state = fe->demodulator_priv;
 424
 425         *status = 0;
 426
 427         core_status = nxt6000_readreg(state, OFDM_COR_STAT);
 428
 429         if (core_status & AGCLOCKED)
 430                 *status |= FE_HAS_SIGNAL;
 431
 432         if (nxt6000_readreg(state, OFDM_SYR_STAT) & GI14_SYR_LOCK)
 433                 *status |= FE_HAS_CARRIER;
 434
 435         if (nxt6000_readreg(state, VIT_SYNC_STATUS) & VITINSYNC)
 436                 *status |= FE_HAS_VITERBI;
 437
 438         if (nxt6000_readreg(state, RS_COR_STAT) & RSCORESTATUS)
 439                 *status |= FE_HAS_SYNC;
 440
 441         if ((core_status & TPSLOCKED) && (*status == (FE_HAS_SIGNAL | FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC)))
 442                 *status |= FE_HAS_LOCK;
 443
 444         if (debug)
 445                 nxt6000_dump_status(state);
 446
 447         return 0;
 448 }
 449
 450 static int nxt6000_init(struct dvb_frontend* fe)
 451 {
 452         struct nxt6000_state* state = fe->demodulator_priv;
 453
 454         nxt6000_reset(state);
 455         nxt6000_setup(fe);
 456
 457         return 0;
 458 }
 459
 460 static int nxt6000_set_frontend(struct dvb_frontend* fe, struct dvb_frontend_parameters *param)
 461 {
 462         struct nxt6000_state* state = fe->demodulator_priv;
 463         int result;
 464
 465         if (fe->ops.tuner_ops.set_params) {
 466                 fe->ops.tuner_ops.set_params(fe, param);
 467                 if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
 468         }
 469
 470         if ((result = nxt6000_set_bandwidth(state, param->u.ofdm.bandwidth)) < 0)
 471                 return result;
 472         if ((result = nxt6000_set_guard_interval(state, param->u.ofdm.guard_interval)) < 0)
 473                 return result;
 474         if ((result = nxt6000_set_transmission_mode(state, param->u.ofdm.transmission_mode)) < 0)
 475                 return result;
 476         if ((result = nxt6000_set_inversion(state, param->inversion)) < 0)
 477                 return result;
 478
 479         msleep(500);
 480         return 0;
 481 }
 482
 483 static void nxt6000_release(struct dvb_frontend* fe)
 484 {
 485         struct nxt6000_state* state = fe->demodulator_priv;
 486         kfree(state);
 487 }
 488
 489 static int nxt6000_read_snr(struct dvb_frontend* fe, u16* snr)
 490 {
 491         struct nxt6000_state* state = fe->demodulator_priv;
 492
 493         *snr = nxt6000_readreg( state, OFDM_CHC_SNR) / 8;
 494
 495         return 0;
 496 }
 497
 498 static int nxt6000_read_ber(struct dvb_frontend* fe, u32* ber)
 499 {
 500         struct nxt6000_state* state = fe->demodulator_priv;
 501
 502         nxt6000_writereg( state, VIT_COR_INTSTAT, 0x18 );
 503
 504         *ber = (nxt6000_readreg( state, VIT_BER_1 ) << 8 ) |
 505                 nxt6000_readreg( state, VIT_BER_0 );
 506
 507         nxt6000_writereg( state, VIT_COR_INTSTAT, 0x18); // Clear BER Done interrupts
 508
 509         return 0;
 510 }
 511
 512 static int nxt6000_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
 513 {
 514         struct nxt6000_state* state = fe->demodulator_priv;
 515
 516         *signal_strength = (short) (511 -
 517                 (nxt6000_readreg(state, AGC_GAIN_1) +
 518                 ((nxt6000_readreg(state, AGC_GAIN_2) & 0x03) << 8)));
 519
 520         return 0;
 521 }
 522
 523 static int nxt6000_fe_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings *tune)
 524 {
 525         tune->min_delay_ms = 500;
 526         return 0;
 527 }
 528
 529 static int nxt6000_i2c_gate_ctrl(struct dvb_frontend* fe, int enable)
 530 {
 531         struct nxt6000_state* state = fe->demodulator_priv;
 532
 533         if (enable) {
 534                 return nxt6000_writereg(state, ENABLE_TUNER_IIC, 0x01);
 535         } else {
 536                 return nxt6000_writereg(state, ENABLE_TUNER_IIC, 0x00);
 537         }
 538 }
 539
 540 static struct dvb_frontend_ops nxt6000_ops;
 541
 542 struct dvb_frontend* nxt6000_attach(const struct nxt6000_config* config,
 543                                     struct i2c_adapter* i2c)
 544 {
 545         struct nxt6000_state* state = NULL;
 546
 547         /* allocate memory for the internal state */
 548         state = kzalloc(sizeof(struct nxt6000_state), GFP_KERNEL);
 549         if (state == NULL) goto error;
 550
 551         /* setup the state */
 552         state->config = config;
 553         state->i2c = i2c;
 554
 555         /* check if the demod is there */
 556         if (nxt6000_readreg(state, OFDM_MSC_REV) != NXT6000ASICDEVICE) goto error;
 557
 558         /* create dvb_frontend */
 559         memcpy(&state->frontend.ops, &nxt6000_ops, sizeof(struct dvb_frontend_ops));
 560         state->frontend.demodulator_priv = state;
 561         return &state->frontend;
 562
 563 error:
 564         kfree(state);
 565         return NULL;
 566 }
 567
 568 static struct dvb_frontend_ops nxt6000_ops = {
 569
 570         .info = {
 571                 .name = "NxtWave NXT6000 DVB-T",
 572                 .type = FE_OFDM,
 573                 .frequency_min = 0,
 574                 .frequency_max = 863250000,
 575                 .frequency_stepsize = 62500,
 576                 /*.frequency_tolerance = *//* FIXME: 12% of SR */
 577                 .symbol_rate_min = 0,   /* FIXME */
 578                 .symbol_rate_max = 9360000,     /* FIXME */
 579                 .symbol_rate_tolerance = 4000,
 580                 .caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
 581                         FE_CAN_FEC_4_5 | FE_CAN_FEC_5_6 | FE_CAN_FEC_6_7 |
 582                         FE_CAN_FEC_7_8 | FE_CAN_FEC_8_9 | FE_CAN_FEC_AUTO |
 583                         FE_CAN_QAM_16 | FE_CAN_QAM_64 | FE_CAN_QAM_AUTO |
 584                         FE_CAN_TRANSMISSION_MODE_AUTO | FE_CAN_GUARD_INTERVAL_AUTO |
 585                         FE_CAN_HIERARCHY_AUTO,
 586         },
 587
 588         .release = nxt6000_release,
 589
 590         .init = nxt6000_init,
 591         .i2c_gate_ctrl = nxt6000_i2c_gate_ctrl,
 592
 593         .get_tune_settings = nxt6000_fe_get_tune_settings,
 594
 595         .set_frontend = nxt6000_set_frontend,
 596
 597         .read_status = nxt6000_read_status,
 598         .read_ber = nxt6000_read_ber,
 599         .read_signal_strength = nxt6000_read_signal_strength,
 600         .read_snr = nxt6000_read_snr,
 601 };
 602
 603 module_param(debug, int, 0644);
 604 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
 605
 606 MODULE_DESCRIPTION("NxtWave NXT6000 DVB-T demodulator driver");
 607 MODULE_AUTHOR("Florian Schirmer");
 608 MODULE_LICENSE("GPL");
 609
 610 EXPORT_SYMBOL(nxt6000_attach);