drivers/media/dvb-frontends/cx22702.c

   1 /*
   2     Conexant 22702 DVB OFDM demodulator driver
   3
   4     based on:
   5         Alps TDMB7 DVB OFDM demodulator driver
   6
   7     Copyright (C) 2001-2002 Convergence Integrated Media GmbH
   8           Holger Waechtler <holger@convergence.de>
   9
  10     Copyright (C) 2004 Steven Toth <stoth@linuxtv.org>
  11
  12     This program is free software; you can redistribute it and/or modify
  13     it under the terms of the GNU General Public License as published by
  14     the Free Software Foundation; either version 2 of the License, or
  15     (at your option) any later version.
  16
  17     This program is distributed in the hope that it will be useful,
  18     but WITHOUT ANY WARRANTY; without even the implied warranty of
  19     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20     GNU General Public License for more details.
  21
  22     You should have received a copy of the GNU General Public License
  23     along with this program; if not, write to the Free Software
  24     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25
  26 */
  27
  28 #include <linux/kernel.h>
  29 #include <linux/init.h>
  30 #include <linux/module.h>
  31 #include <linux/string.h>
  32 #include <linux/slab.h>
  33 #include <linux/delay.h>
  34 #include "dvb_frontend.h"
  35 #include "cx22702.h"
  36
  37 struct cx22702_state {
  38
  39         struct i2c_adapter *i2c;
  40
  41         /* configuration settings */
  42         const struct cx22702_config *config;
  43
  44         struct dvb_frontend frontend;
  45
  46         /* previous uncorrected block counter */
  47         u8 prevUCBlocks;
  48 };
  49
  50 static int debug;
  51 module_param(debug, int, 0644);
  52 MODULE_PARM_DESC(debug, "Enable verbose debug messages");
  53
  54 #define dprintk if (debug) printk
  55
  56 /* Register values to initialise the demod */
  57 static const u8 init_tab[] = {
  58         0x00, 0x00, /* Stop acquisition */
  59         0x0B, 0x06,
  60         0x09, 0x01,
  61         0x0D, 0x41,
  62         0x16, 0x32,
  63         0x20, 0x0A,
  64         0x21, 0x17,
  65         0x24, 0x3e,
  66         0x26, 0xff,
  67         0x27, 0x10,
  68         0x28, 0x00,
  69         0x29, 0x00,
  70         0x2a, 0x10,
  71         0x2b, 0x00,
  72         0x2c, 0x10,
  73         0x2d, 0x00,
  74         0x48, 0xd4,
  75         0x49, 0x56,
  76         0x6b, 0x1e,
  77         0xc8, 0x02,
  78         0xf9, 0x00,
  79         0xfa, 0x00,
  80         0xfb, 0x00,
  81         0xfc, 0x00,
  82         0xfd, 0x00,
  83 };
  84
  85 static int cx22702_writereg(struct cx22702_state *state, u8 reg, u8 data)
  86 {
  87         int ret;
  88         u8 buf[] = { reg, data };
  89         struct i2c_msg msg = {
  90                 .addr = state->config->demod_address, .flags = 0,
  91                         .buf = buf, .len = 2 };
  92
  93         ret = i2c_transfer(state->i2c, &msg, 1);
  94
  95         if (unlikely(ret != 1)) {
  96                 printk(KERN_ERR
  97                         "%s: error (reg == 0x%02x, val == 0x%02x, ret == %i)\n",
  98                         __func__, reg, data, ret);
  99                 return -1;
 100         }
 101
 102         return 0;
 103 }
 104
 105 static u8 cx22702_readreg(struct cx22702_state *state, u8 reg)
 106 {
 107         int ret;
 108         u8 data;
 109
 110         struct i2c_msg msg[] = {
 111                 { .addr = state->config->demod_address, .flags = 0,
 112                         .buf = &reg, .len = 1 },
 113                 { .addr = state->config->demod_address, .flags = I2C_M_RD,
 114                         .buf = &data, .len = 1 } };
 115
 116         ret = i2c_transfer(state->i2c, msg, 2);
 117
 118         if (unlikely(ret != 2)) {
 119                 printk(KERN_ERR "%s: error (reg == 0x%02x, ret == %i)\n",
 120                         __func__, reg, ret);
 121                 return 0;
 122         }
 123
 124         return data;
 125 }
 126
 127 static int cx22702_set_inversion(struct cx22702_state *state, int inversion)
 128 {
 129         u8 val;
 130
 131         val = cx22702_readreg(state, 0x0C);
 132         switch (inversion) {
 133         case INVERSION_AUTO:
 134                 return -EOPNOTSUPP;
 135         case INVERSION_ON:
 136                 val |= 0x01;
 137                 break;
 138         case INVERSION_OFF:
 139                 val &= 0xfe;
 140                 break;
 141         default:
 142                 return -EINVAL;
 143         }
 144         return cx22702_writereg(state, 0x0C, val);
 145 }
 146
 147 /* Retrieve the demod settings */
 148 static int cx22702_get_tps(struct cx22702_state *state,
 149                            struct dtv_frontend_properties *p)
 150 {
 151         u8 val;
 152
 153         /* Make sure the TPS regs are valid */
 154         if (!(cx22702_readreg(state, 0x0A) & 0x20))
 155                 return -EAGAIN;
 156
 157         val = cx22702_readreg(state, 0x01);
 158         switch ((val & 0x18) >> 3) {
 159         case 0:
 160                 p->modulation = QPSK;
 161                 break;
 162         case 1:
 163                 p->modulation = QAM_16;
 164                 break;
 165         case 2:
 166                 p->modulation = QAM_64;
 167                 break;
 168         }
 169         switch (val & 0x07) {
 170         case 0:
 171                 p->hierarchy = HIERARCHY_NONE;
 172                 break;
 173         case 1:
 174                 p->hierarchy = HIERARCHY_1;
 175                 break;
 176         case 2:
 177                 p->hierarchy = HIERARCHY_2;
 178                 break;
 179         case 3:
 180                 p->hierarchy = HIERARCHY_4;
 181                 break;
 182         }
 183
 184
 185         val = cx22702_readreg(state, 0x02);
 186         switch ((val & 0x38) >> 3) {
 187         case 0:
 188                 p->code_rate_HP = FEC_1_2;
 189                 break;
 190         case 1:
 191                 p->code_rate_HP = FEC_2_3;
 192                 break;
 193         case 2:
 194                 p->code_rate_HP = FEC_3_4;
 195                 break;
 196         case 3:
 197                 p->code_rate_HP = FEC_5_6;
 198                 break;
 199         case 4:
 200                 p->code_rate_HP = FEC_7_8;
 201                 break;
 202         }
 203         switch (val & 0x07) {
 204         case 0:
 205                 p->code_rate_LP = FEC_1_2;
 206                 break;
 207         case 1:
 208                 p->code_rate_LP = FEC_2_3;
 209                 break;
 210         case 2:
 211                 p->code_rate_LP = FEC_3_4;
 212                 break;
 213         case 3:
 214                 p->code_rate_LP = FEC_5_6;
 215                 break;
 216         case 4:
 217                 p->code_rate_LP = FEC_7_8;
 218                 break;
 219         }
 220
 221         val = cx22702_readreg(state, 0x03);
 222         switch ((val & 0x0c) >> 2) {
 223         case 0:
 224                 p->guard_interval = GUARD_INTERVAL_1_32;
 225                 break;
 226         case 1:
 227                 p->guard_interval = GUARD_INTERVAL_1_16;
 228                 break;
 229         case 2:
 230                 p->guard_interval = GUARD_INTERVAL_1_8;
 231                 break;
 232         case 3:
 233                 p->guard_interval = GUARD_INTERVAL_1_4;
 234                 break;
 235         }
 236         switch (val & 0x03) {
 237         case 0:
 238                 p->transmission_mode = TRANSMISSION_MODE_2K;
 239                 break;
 240         case 1:
 241                 p->transmission_mode = TRANSMISSION_MODE_8K;
 242                 break;
 243         }
 244
 245         return 0;
 246 }
 247
 248 static int cx22702_i2c_gate_ctrl(struct dvb_frontend *fe, int enable)
 249 {
 250         struct cx22702_state *state = fe->demodulator_priv;
 251         u8 val;
 252
 253         dprintk("%s(%d)\n", __func__, enable);
 254         val = cx22702_readreg(state, 0x0D);
 255         if (enable)
 256                 val &= 0xfe;
 257         else
 258                 val |= 0x01;
 259         return cx22702_writereg(state, 0x0D, val);
 260 }
 261
 262 /* Talk to the demod, set the FEC, GUARD, QAM settings etc */
 263 static int cx22702_set_tps(struct dvb_frontend *fe)
 264 {
 265         struct dtv_frontend_properties *p = &fe->dtv_property_cache;
 266         u8 val;
 267         struct cx22702_state *state = fe->demodulator_priv;
 268
 269         if (fe->ops.tuner_ops.set_params) {
 270                 fe->ops.tuner_ops.set_params(fe);
 271                 if (fe->ops.i2c_gate_ctrl)
 272                         fe->ops.i2c_gate_ctrl(fe, 0);
 273         }
 274
 275         /* set inversion */
 276         cx22702_set_inversion(state, p->inversion);
 277
 278         /* set bandwidth */
 279         val = cx22702_readreg(state, 0x0C) & 0xcf;
 280         switch (p->bandwidth_hz) {
 281         case 6000000:
 282                 val |= 0x20;
 283                 break;
 284         case 7000000:
 285                 val |= 0x10;
 286                 break;
 287         case 8000000:
 288                 break;
 289         default:
 290                 dprintk("%s: invalid bandwidth\n", __func__);
 291                 return -EINVAL;
 292         }
 293         cx22702_writereg(state, 0x0C, val);
 294
 295         p->code_rate_LP = FEC_AUTO; /* temp hack as manual not working */
 296
 297         /* use auto configuration? */
 298         if ((p->hierarchy == HIERARCHY_AUTO) ||
 299            (p->modulation == QAM_AUTO) ||
 300            (p->code_rate_HP == FEC_AUTO) ||
 301            (p->code_rate_LP == FEC_AUTO) ||
 302            (p->guard_interval == GUARD_INTERVAL_AUTO) ||
 303            (p->transmission_mode == TRANSMISSION_MODE_AUTO)) {
 304
 305                 /* TPS Source - use hardware driven values */
 306                 cx22702_writereg(state, 0x06, 0x10);
 307                 cx22702_writereg(state, 0x07, 0x9);
 308                 cx22702_writereg(state, 0x08, 0xC1);
 309                 cx22702_writereg(state, 0x0B, cx22702_readreg(state, 0x0B)
 310                         & 0xfc);
 311                 cx22702_writereg(state, 0x0C,
 312                         (cx22702_readreg(state, 0x0C) & 0xBF) | 0x40);
 313                 cx22702_writereg(state, 0x00, 0x01); /* Begin acquisition */
 314                 dprintk("%s: Autodetecting\n", __func__);
 315                 return 0;
 316         }
 317
 318         /* manually programmed values */
 319         switch (p->modulation) {                /* mask 0x18 */
 320         case QPSK:
 321                 val = 0x00;
 322                 break;
 323         case QAM_16:
 324                 val = 0x08;
 325                 break;
 326         case QAM_64:
 327                 val = 0x10;
 328                 break;
 329         default:
 330                 dprintk("%s: invalid modulation\n", __func__);
 331                 return -EINVAL;
 332         }
 333         switch (p->hierarchy) { /* mask 0x07 */
 334         case HIERARCHY_NONE:
 335                 break;
 336         case HIERARCHY_1:
 337                 val |= 0x01;
 338                 break;
 339         case HIERARCHY_2:
 340                 val |= 0x02;
 341                 break;
 342         case HIERARCHY_4:
 343                 val |= 0x03;
 344                 break;
 345         default:
 346                 dprintk("%s: invalid hierarchy\n", __func__);
 347                 return -EINVAL;
 348         }
 349         cx22702_writereg(state, 0x06, val);
 350
 351         switch (p->code_rate_HP) {              /* mask 0x38 */
 352         case FEC_NONE:
 353         case FEC_1_2:
 354                 val = 0x00;
 355                 break;
 356         case FEC_2_3:
 357                 val = 0x08;
 358                 break;
 359         case FEC_3_4:
 360                 val = 0x10;
 361                 break;
 362         case FEC_5_6:
 363                 val = 0x18;
 364                 break;
 365         case FEC_7_8:
 366                 val = 0x20;
 367                 break;
 368         default:
 369                 dprintk("%s: invalid code_rate_HP\n", __func__);
 370                 return -EINVAL;
 371         }
 372         switch (p->code_rate_LP) {              /* mask 0x07 */
 373         case FEC_NONE:
 374         case FEC_1_2:
 375                 break;
 376         case FEC_2_3:
 377                 val |= 0x01;
 378                 break;
 379         case FEC_3_4:
 380                 val |= 0x02;
 381                 break;
 382         case FEC_5_6:
 383                 val |= 0x03;
 384                 break;
 385         case FEC_7_8:
 386                 val |= 0x04;
 387                 break;
 388         default:
 389                 dprintk("%s: invalid code_rate_LP\n", __func__);
 390                 return -EINVAL;
 391         }
 392         cx22702_writereg(state, 0x07, val);
 393
 394         switch (p->guard_interval) {            /* mask 0x0c */
 395         case GUARD_INTERVAL_1_32:
 396                 val = 0x00;
 397                 break;
 398         case GUARD_INTERVAL_1_16:
 399                 val = 0x04;
 400                 break;
 401         case GUARD_INTERVAL_1_8:
 402                 val = 0x08;
 403                 break;
 404         case GUARD_INTERVAL_1_4:
 405                 val = 0x0c;
 406                 break;
 407         default:
 408                 dprintk("%s: invalid guard_interval\n", __func__);
 409                 return -EINVAL;
 410         }
 411         switch (p->transmission_mode) {         /* mask 0x03 */
 412         case TRANSMISSION_MODE_2K:
 413                 break;
 414         case TRANSMISSION_MODE_8K:
 415                 val |= 0x1;
 416                 break;
 417         default:
 418                 dprintk("%s: invalid transmission_mode\n", __func__);
 419                 return -EINVAL;
 420         }
 421         cx22702_writereg(state, 0x08, val);
 422         cx22702_writereg(state, 0x0B,
 423                 (cx22702_readreg(state, 0x0B) & 0xfc) | 0x02);
 424         cx22702_writereg(state, 0x0C,
 425                 (cx22702_readreg(state, 0x0C) & 0xBF) | 0x40);
 426
 427         /* Begin channel acquisition */
 428         cx22702_writereg(state, 0x00, 0x01);
 429
 430         return 0;
 431 }
 432
 433 /* Reset the demod hardware and reset all of the configuration registers
 434    to a default state. */
 435 static int cx22702_init(struct dvb_frontend *fe)
 436 {
 437         int i;
 438         struct cx22702_state *state = fe->demodulator_priv;
 439
 440         cx22702_writereg(state, 0x00, 0x02);
 441
 442         msleep(10);
 443
 444         for (i = 0; i < ARRAY_SIZE(init_tab); i += 2)
 445                 cx22702_writereg(state, init_tab[i], init_tab[i + 1]);
 446
 447         cx22702_writereg(state, 0xf8, (state->config->output_mode << 1)
 448                 & 0x02);
 449
 450         cx22702_i2c_gate_ctrl(fe, 0);
 451
 452         return 0;
 453 }
 454
 455 static int cx22702_read_status(struct dvb_frontend *fe, fe_status_t *status)
 456 {
 457         struct cx22702_state *state = fe->demodulator_priv;
 458         u8 reg0A;
 459         u8 reg23;
 460
 461         *status = 0;
 462
 463         reg0A = cx22702_readreg(state, 0x0A);
 464         reg23 = cx22702_readreg(state, 0x23);
 465
 466         dprintk("%s: status demod=0x%02x agc=0x%02x\n"
 467                 , __func__, reg0A, reg23);
 468
 469         if (reg0A & 0x10) {
 470                 *status |= FE_HAS_LOCK;
 471                 *status |= FE_HAS_VITERBI;
 472                 *status |= FE_HAS_SYNC;
 473         }
 474
 475         if (reg0A & 0x20)
 476                 *status |= FE_HAS_CARRIER;
 477
 478         if (reg23 < 0xf0)
 479                 *status |= FE_HAS_SIGNAL;
 480
 481         return 0;
 482 }
 483
 484 static int cx22702_read_ber(struct dvb_frontend *fe, u32 *ber)
 485 {
 486         struct cx22702_state *state = fe->demodulator_priv;
 487
 488         if (cx22702_readreg(state, 0xE4) & 0x02) {
 489                 /* Realtime statistics */
 490                 *ber = (cx22702_readreg(state, 0xDE) & 0x7F) << 7
 491                         | (cx22702_readreg(state, 0xDF) & 0x7F);
 492         } else {
 493                 /* Averagtine statistics */
 494                 *ber = (cx22702_readreg(state, 0xDE) & 0x7F) << 7
 495                         | cx22702_readreg(state, 0xDF);
 496         }
 497
 498         return 0;
 499 }
 500
 501 static int cx22702_read_signal_strength(struct dvb_frontend *fe,
 502         u16 *signal_strength)
 503 {
 504         struct cx22702_state *state = fe->demodulator_priv;
 505         u8 reg23;
 506
 507         /*
 508          * Experience suggests that the strength signal register works as
 509          * follows:
 510          * - In the absence of signal, value is 0xff.
 511          * - In the presence of a weak signal, bit 7 is set, not sure what
 512          *   the lower 7 bits mean.
 513          * - In the presence of a strong signal, the register holds a 7-bit
 514          *   value (bit 7 is cleared), with greater values standing for
 515          *   weaker signals.
 516          */
 517         reg23 = cx22702_readreg(state, 0x23);
 518         if (reg23 & 0x80) {
 519                 *signal_strength = 0;
 520         } else {
 521                 reg23 = ~reg23 & 0x7f;
 522                 /* Scale to 16 bit */
 523                 *signal_strength = (reg23 << 9) | (reg23 << 2) | (reg23 >> 5);
 524         }
 525
 526         return 0;
 527 }
 528
 529 static int cx22702_read_snr(struct dvb_frontend *fe, u16 *snr)
 530 {
 531         struct cx22702_state *state = fe->demodulator_priv;
 532
 533         u16 rs_ber;
 534         if (cx22702_readreg(state, 0xE4) & 0x02) {
 535                 /* Realtime statistics */
 536                 rs_ber = (cx22702_readreg(state, 0xDE) & 0x7F) << 7
 537                         | (cx22702_readreg(state, 0xDF) & 0x7F);
 538         } else {
 539                 /* Averagine statistics */
 540                 rs_ber = (cx22702_readreg(state, 0xDE) & 0x7F) << 8
 541                         | cx22702_readreg(state, 0xDF);
 542         }
 543         *snr = ~rs_ber;
 544
 545         return 0;
 546 }
 547
 548 static int cx22702_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
 549 {
 550         struct cx22702_state *state = fe->demodulator_priv;
 551
 552         u8 _ucblocks;
 553
 554         /* RS Uncorrectable Packet Count then reset */
 555         _ucblocks = cx22702_readreg(state, 0xE3);
 556         if (state->prevUCBlocks < _ucblocks)
 557                 *ucblocks = (_ucblocks - state->prevUCBlocks);
 558         else
 559                 *ucblocks = state->prevUCBlocks - _ucblocks;
 560         state->prevUCBlocks = _ucblocks;
 561
 562         return 0;
 563 }
 564
 565 static int cx22702_get_frontend(struct dvb_frontend *fe)
 566 {
 567         struct dtv_frontend_properties *c = &fe->dtv_property_cache;
 568         struct cx22702_state *state = fe->demodulator_priv;
 569
 570         u8 reg0C = cx22702_readreg(state, 0x0C);
 571
 572         c->inversion = reg0C & 0x1 ? INVERSION_ON : INVERSION_OFF;
 573         return cx22702_get_tps(state, c);
 574 }
 575
 576 static int cx22702_get_tune_settings(struct dvb_frontend *fe,
 577         struct dvb_frontend_tune_settings *tune)
 578 {
 579         tune->min_delay_ms = 1000;
 580         return 0;
 581 }
 582
 583 static void cx22702_release(struct dvb_frontend *fe)
 584 {
 585         struct cx22702_state *state = fe->demodulator_priv;
 586         kfree(state);
 587 }
 588
 589 static const struct dvb_frontend_ops cx22702_ops;
 590
 591 struct dvb_frontend *cx22702_attach(const struct cx22702_config *config,
 592         struct i2c_adapter *i2c)
 593 {
 594         struct cx22702_state *state = NULL;
 595
 596         /* allocate memory for the internal state */
 597         state = kzalloc(sizeof(struct cx22702_state), GFP_KERNEL);
 598         if (state == NULL)
 599                 goto error;
 600
 601         /* setup the state */
 602         state->config = config;
 603         state->i2c = i2c;
 604
 605         /* check if the demod is there */
 606         if (cx22702_readreg(state, 0x1f) != 0x3)
 607                 goto error;
 608
 609         /* create dvb_frontend */
 610         memcpy(&state->frontend.ops, &cx22702_ops,
 611                 sizeof(struct dvb_frontend_ops));
 612         state->frontend.demodulator_priv = state;
 613         return &state->frontend;
 614
 615 error:
 616         kfree(state);
 617         return NULL;
 618 }
 619 EXPORT_SYMBOL(cx22702_attach);
 620
 621 static const struct dvb_frontend_ops cx22702_ops = {
 622         .delsys = { SYS_DVBT },
 623         .info = {
 624                 .name                   = "Conexant CX22702 DVB-T",
 625                 .frequency_min          = 177000000,
 626                 .frequency_max          = 858000000,
 627                 .frequency_stepsize     = 166666,
 628                 .caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
 629                 FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
 630                 FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 | FE_CAN_QAM_AUTO |
 631                 FE_CAN_HIERARCHY_AUTO | FE_CAN_GUARD_INTERVAL_AUTO |
 632                 FE_CAN_TRANSMISSION_MODE_AUTO | FE_CAN_RECOVER
 633         },
 634
 635         .release = cx22702_release,
 636
 637         .init = cx22702_init,
 638         .i2c_gate_ctrl = cx22702_i2c_gate_ctrl,
 639
 640         .set_frontend = cx22702_set_tps,
 641         .get_frontend = cx22702_get_frontend,
 642         .get_tune_settings = cx22702_get_tune_settings,
 643
 644         .read_status = cx22702_read_status,
 645         .read_ber = cx22702_read_ber,
 646         .read_signal_strength = cx22702_read_signal_strength,
 647         .read_snr = cx22702_read_snr,
 648         .read_ucblocks = cx22702_read_ucblocks,
 649 };
 650
 651 MODULE_DESCRIPTION("Conexant CX22702 DVB-T Demodulator driver");
 652 MODULE_AUTHOR("Steven Toth");
 653 MODULE_LICENSE("GPL");