drivers/media/dvb/frontends/at76c651.c

   1 /*
   2  * at76c651.c
   3  *
   4  * Atmel DVB-C Frontend Driver (at76c651/tua6010xs)
   5  *
   6  * Copyright (C) 2001 fnbrd <fnbrd@gmx.de>
   7  *             & 2002-2004 Andreas Oberritter <obi@linuxtv.org>
   8  *             & 2003 Wolfram Joost <dbox2@frokaschwei.de>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  23  *
  24  * AT76C651
  25  * http://www.nalanda.nitc.ac.in/industry/datasheets/atmel/acrobat/doc1293.pdf
  26  * http://www.atmel.com/atmel/acrobat/doc1320.pdf
  27  */
  28
  29 #include <linux/init.h>
  30 #include <linux/module.h>
  31 #include <linux/moduleparam.h>
  32 #include <linux/kernel.h>
  33 #include <linux/string.h>
  34 #include <linux/slab.h>
  35 #include <linux/bitops.h>
  36 #include "dvb_frontend.h"
  37 #include "at76c651.h"
  38
  39
  40 struct at76c651_state {
  41
  42         struct i2c_adapter* i2c;
  43
  44         struct dvb_frontend_ops ops;
  45
  46         const struct at76c651_config* config;
  47
  48         struct dvb_frontend frontend;
  49
  50         /* revision of the chip */
  51         u8 revision;
  52
  53         /* last QAM value set */
  54         u8 qam;
  55 };
  56
  57 static int debug;
  58 #define dprintk(args...) \
  59         do { \
  60                 if (debug) printk(KERN_DEBUG "at76c651: " args); \
  61         } while (0)
  62
  63
  64 #if ! defined(__powerpc__)
  65 static __inline__ int __ilog2(unsigned long x)
  66 {
  67         int i;
  68
  69         if (x == 0)
  70                 return -1;
  71
  72         for (i = 0; x != 0; i++)
  73                 x >>= 1;
  74
  75         return i - 1;
  76 }
  77 #endif
  78
  79 static int at76c651_writereg(struct at76c651_state* state, u8 reg, u8 data)
  80 {
  81         int ret;
  82         u8 buf[] = { reg, data };
  83         struct i2c_msg msg =
  84                 { .addr = state->config->demod_address, .flags = 0, .buf = buf, .len = 2 };
  85
  86         ret = i2c_transfer(state->i2c, &msg, 1);
  87
  88         if (ret != 1)
  89                 dprintk("%s: writereg error "
  90                         "(reg == 0x%02x, val == 0x%02x, ret == %i)\n",
  91                         __FUNCTION__, reg, data, ret);
  92
  93         msleep(10);
  94
  95         return (ret != 1) ? -EREMOTEIO : 0;
  96 }
  97
  98 static u8 at76c651_readreg(struct at76c651_state* state, u8 reg)
  99 {
 100         int ret;
 101         u8 val;
 102         struct i2c_msg msg[] = {
 103                 { .addr = state->config->demod_address, .flags = 0, .buf = &reg, .len = 1 },
 104                 { .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = &val, .len = 1 }
 105         };
 106
 107         ret = i2c_transfer(state->i2c, msg, 2);
 108
 109         if (ret != 2)
 110                 dprintk("%s: readreg error (ret == %i)\n", __FUNCTION__, ret);
 111
 112         return val;
 113 }
 114
 115 static int at76c651_reset(struct at76c651_state* state)
 116 {
 117         return at76c651_writereg(state, 0x07, 0x01);
 118 }
 119
 120 static void at76c651_disable_interrupts(struct at76c651_state* state)
 121 {
 122         at76c651_writereg(state, 0x0b, 0x00);
 123 }
 124
 125 static int at76c651_set_auto_config(struct at76c651_state *state)
 126 {
 127         /*
 128          * Autoconfig
 129          */
 130
 131         at76c651_writereg(state, 0x06, 0x01);
 132
 133         /*
 134          * Performance optimizations, should be done after autoconfig
 135          */
 136
 137         at76c651_writereg(state, 0x10, 0x06);
 138         at76c651_writereg(state, 0x11, ((state->qam == 5) || (state->qam == 7)) ? 0x12 : 0x10);
 139         at76c651_writereg(state, 0x15, 0x28);
 140         at76c651_writereg(state, 0x20, 0x09);
 141         at76c651_writereg(state, 0x24, ((state->qam == 5) || (state->qam == 7)) ? 0xC0 : 0x90);
 142         at76c651_writereg(state, 0x30, 0x90);
 143         if (state->qam == 5)
 144                 at76c651_writereg(state, 0x35, 0x2A);
 145
 146         /*
 147          * Initialize A/D-converter
 148          */
 149
 150         if (state->revision == 0x11) {
 151                 at76c651_writereg(state, 0x2E, 0x38);
 152                 at76c651_writereg(state, 0x2F, 0x13);
 153         }
 154
 155         at76c651_disable_interrupts(state);
 156
 157         /*
 158          * Restart operation
 159          */
 160
 161         at76c651_reset(state);
 162
 163         return 0;
 164 }
 165
 166 static void at76c651_set_bbfreq(struct at76c651_state* state)
 167 {
 168         at76c651_writereg(state, 0x04, 0x3f);
 169         at76c651_writereg(state, 0x05, 0xee);
 170 }
 171
 172 static int at76c651_set_symbol_rate(struct at76c651_state* state, u32 symbol_rate)
 173 {
 174         u8 exponent;
 175         u32 mantissa;
 176
 177         if (symbol_rate > 9360000)
 178                 return -EINVAL;
 179
 180         /*
 181          * FREF = 57800 kHz
 182          * exponent = 10 + floor (log2(symbol_rate / FREF))
 183          * mantissa = (symbol_rate / FREF) * (1 << (30 - exponent))
 184          */
 185
 186         exponent = __ilog2((symbol_rate << 4) / 903125);
 187         mantissa = ((symbol_rate / 3125) * (1 << (24 - exponent))) / 289;
 188
 189         at76c651_writereg(state, 0x00, mantissa >> 13);
 190         at76c651_writereg(state, 0x01, mantissa >> 5);
 191         at76c651_writereg(state, 0x02, (mantissa << 3) | exponent);
 192
 193         return 0;
 194 }
 195
 196 static int at76c651_set_qam(struct at76c651_state *state, fe_modulation_t qam)
 197 {
 198         switch (qam) {
 199         case QPSK:
 200                 state->qam = 0x02;
 201                 break;
 202         case QAM_16:
 203                 state->qam = 0x04;
 204                 break;
 205         case QAM_32:
 206                 state->qam = 0x05;
 207                 break;
 208         case QAM_64:
 209                 state->qam = 0x06;
 210                 break;
 211         case QAM_128:
 212                 state->qam = 0x07;
 213                 break;
 214         case QAM_256:
 215                 state->qam = 0x08;
 216                 break;
 217 #if 0
 218         case QAM_512:
 219                 state->qam = 0x09;
 220                 break;
 221         case QAM_1024:
 222                 state->qam = 0x0A;
 223                 break;
 224 #endif
 225         default:
 226                 return -EINVAL;
 227
 228         }
 229
 230         return at76c651_writereg(state, 0x03, state->qam);
 231 }
 232
 233 static int at76c651_set_inversion(struct at76c651_state* state, fe_spectral_inversion_t inversion)
 234 {
 235         u8 feciqinv = at76c651_readreg(state, 0x60);
 236
 237         switch (inversion) {
 238         case INVERSION_OFF:
 239                 feciqinv |= 0x02;
 240                 feciqinv &= 0xFE;
 241                 break;
 242
 243         case INVERSION_ON:
 244                 feciqinv |= 0x03;
 245                 break;
 246
 247         case INVERSION_AUTO:
 248                 feciqinv &= 0xFC;
 249                 break;
 250
 251         default:
 252                 return -EINVAL;
 253         }
 254
 255         return at76c651_writereg(state, 0x60, feciqinv);
 256 }
 257
 258 static int at76c651_set_parameters(struct dvb_frontend* fe,
 259                                    struct dvb_frontend_parameters *p)
 260 {
 261         int ret;
 262         struct at76c651_state* state = fe->demodulator_priv;
 263
 264         at76c651_writereg(state, 0x0c, 0xc3);
 265         state->config->pll_set(fe, p);
 266         at76c651_writereg(state, 0x0c, 0xc2);
 267
 268         if ((ret = at76c651_set_symbol_rate(state, p->u.qam.symbol_rate)))
 269                 return ret;
 270
 271         if ((ret = at76c651_set_inversion(state, p->inversion)))
 272                 return ret;
 273
 274         return at76c651_set_auto_config(state);
 275 }
 276
 277 static int at76c651_set_defaults(struct dvb_frontend* fe)
 278 {
 279         struct at76c651_state* state = fe->demodulator_priv;
 280
 281         at76c651_set_symbol_rate(state, 6900000);
 282         at76c651_set_qam(state, QAM_64);
 283         at76c651_set_bbfreq(state);
 284         at76c651_set_auto_config(state);
 285
 286         if (state->config->pll_init) {
 287                 at76c651_writereg(state, 0x0c, 0xc3);
 288                 state->config->pll_init(fe);
 289                 at76c651_writereg(state, 0x0c, 0xc2);
 290         }
 291
 292         return 0;
 293 }
 294
 295 static int at76c651_read_status(struct dvb_frontend* fe, fe_status_t* status)
 296 {
 297         struct at76c651_state* state = fe->demodulator_priv;
 298         u8 sync;
 299
 300         /*
 301          * Bits: FEC, CAR, EQU, TIM, AGC2, AGC1, ADC, PLL (PLL=0)
 302          */
 303         sync = at76c651_readreg(state, 0x80);
 304         *status = 0;
 305
 306         if (sync & (0x04 | 0x10))       /* AGC1 || TIM */
 307                 *status |= FE_HAS_SIGNAL;
 308         if (sync & 0x10)                /* TIM */
 309                 *status |= FE_HAS_CARRIER;
 310         if (sync & 0x80)                /* FEC */
 311                 *status |= FE_HAS_VITERBI;
 312         if (sync & 0x40)                /* CAR */
 313                 *status |= FE_HAS_SYNC;
 314         if ((sync & 0xF0) == 0xF0)      /* TIM && EQU && CAR && FEC */
 315                 *status |= FE_HAS_LOCK;
 316
 317         return 0;
 318 }
 319
 320 static int at76c651_read_ber(struct dvb_frontend* fe, u32* ber)
 321 {
 322         struct at76c651_state* state = fe->demodulator_priv;
 323
 324         *ber = (at76c651_readreg(state, 0x81) & 0x0F) << 16;
 325         *ber |= at76c651_readreg(state, 0x82) << 8;
 326         *ber |= at76c651_readreg(state, 0x83);
 327         *ber *= 10;
 328
 329         return 0;
 330 }
 331
 332 static int at76c651_read_signal_strength(struct dvb_frontend* fe, u16* strength)
 333 {
 334         struct at76c651_state* state = fe->demodulator_priv;
 335
 336         u8 gain = ~at76c651_readreg(state, 0x91);
 337         *strength = (gain << 8) | gain;
 338
 339         return 0;
 340 }
 341
 342 static int at76c651_read_snr(struct dvb_frontend* fe, u16* snr)
 343 {
 344         struct at76c651_state* state = fe->demodulator_priv;
 345
 346         *snr = 0xFFFF -
 347             ((at76c651_readreg(state, 0x8F) << 8) |
 348              at76c651_readreg(state, 0x90));
 349
 350         return 0;
 351 }
 352
 353 static int at76c651_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
 354 {
 355         struct at76c651_state* state = fe->demodulator_priv;
 356
 357         *ucblocks = at76c651_readreg(state, 0x82);
 358
 359         return 0;
 360 }
 361
 362 static int at76c651_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings *fesettings)
 363 {
 364         fesettings->min_delay_ms = 50;
 365         fesettings->step_size = 0;
 366         fesettings->max_drift = 0;
 367         return 0;
 368 }
 369
 370 static void at76c651_release(struct dvb_frontend* fe)
 371 {
 372         struct at76c651_state* state = fe->demodulator_priv;
 373         kfree(state);
 374 }
 375
 376 static struct dvb_frontend_ops at76c651_ops;
 377
 378 struct dvb_frontend* at76c651_attach(const struct at76c651_config* config,
 379                                      struct i2c_adapter* i2c)
 380 {
 381         struct at76c651_state* state = NULL;
 382
 383         /* allocate memory for the internal state */
 384         state = kmalloc(sizeof(struct at76c651_state), GFP_KERNEL);
 385         if (state == NULL) goto error;
 386
 387         /* setup the state */
 388         state->config = config;
 389         state->qam = 0;
 390
 391         /* check if the demod is there */
 392         if (at76c651_readreg(state, 0x0e) != 0x65) goto error;
 393
 394         /* finalise state setup */
 395         state->i2c = i2c;
 396         state->revision = at76c651_readreg(state, 0x0f) & 0xfe;
 397         memcpy(&state->ops, &at76c651_ops, sizeof(struct dvb_frontend_ops));
 398
 399         /* create dvb_frontend */
 400         state->frontend.ops = &state->ops;
 401         state->frontend.demodulator_priv = state;
 402         return &state->frontend;
 403
 404 error:
 405         kfree(state);
 406         return NULL;
 407 }
 408
 409 static struct dvb_frontend_ops at76c651_ops = {
 410
 411         .info = {
 412                 .name = "Atmel AT76C651B DVB-C",
 413                 .type = FE_QAM,
 414                 .frequency_min = 48250000,
 415                 .frequency_max = 863250000,
 416                 .frequency_stepsize = 62500,
 417                 /*.frequency_tolerance = */     /* FIXME: 12% of SR */
 418                 .symbol_rate_min = 0,           /* FIXME */
 419                 .symbol_rate_max = 9360000,     /* FIXME */
 420                 .symbol_rate_tolerance = 4000,
 421                 .caps = FE_CAN_INVERSION_AUTO |
 422                     FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
 423                     FE_CAN_FEC_4_5 | FE_CAN_FEC_5_6 | FE_CAN_FEC_6_7 |
 424                     FE_CAN_FEC_7_8 | FE_CAN_FEC_8_9 | FE_CAN_FEC_AUTO |
 425                     FE_CAN_QAM_16 | FE_CAN_QAM_32 | FE_CAN_QAM_64 | FE_CAN_QAM_128 |
 426                     FE_CAN_MUTE_TS | FE_CAN_QAM_256 | FE_CAN_RECOVER
 427         },
 428
 429         .release = at76c651_release,
 430
 431         .init = at76c651_set_defaults,
 432
 433         .set_frontend = at76c651_set_parameters,
 434         .get_tune_settings = at76c651_get_tune_settings,
 435
 436         .read_status = at76c651_read_status,
 437         .read_ber = at76c651_read_ber,
 438         .read_signal_strength = at76c651_read_signal_strength,
 439         .read_snr = at76c651_read_snr,
 440         .read_ucblocks = at76c651_read_ucblocks,
 441 };
 442
 443 module_param(debug, int, 0644);
 444 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
 445
 446 MODULE_DESCRIPTION("Atmel AT76C651 DVB-C Demodulator Driver");
 447 MODULE_AUTHOR("Andreas Oberritter <obi@linuxtv.org>");
 448 MODULE_LICENSE("GPL");
 449
 450 EXPORT_SYMBOL(at76c651_attach);