drivers/media/dvb/frontends/cx22700.c

   1 /*
   2     Conexant cx22700 DVB OFDM demodulator driver
   3
   4     Copyright (C) 2001-2002 Convergence Integrated Media GmbH
   5         Holger Waechtler <holger@convergence.de>
   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
  23 #include <linux/kernel.h>
  24 #include <linux/init.h>
  25 #include <linux/module.h>
  26 #include <linux/moduleparam.h>
  27 #include <linux/string.h>
  28 #include <linux/slab.h>
  29 #include "dvb_frontend.h"
  30 #include "cx22700.h"
  31
  32
  33 struct cx22700_state {
  34
  35         struct i2c_adapter* i2c;
  36
  37         const struct cx22700_config* config;
  38
  39         struct dvb_frontend frontend;
  40 };
  41
  42
  43 static int debug;
  44 #define dprintk(args...) \
  45         do { \
  46                 if (debug) printk(KERN_DEBUG "cx22700: " args); \
  47         } while (0)
  48
  49 static u8 init_tab [] = {
  50         0x04, 0x10,
  51         0x05, 0x09,
  52         0x06, 0x00,
  53         0x08, 0x04,
  54         0x09, 0x00,
  55         0x0a, 0x01,
  56         0x15, 0x40,
  57         0x16, 0x10,
  58         0x17, 0x87,
  59         0x18, 0x17,
  60         0x1a, 0x10,
  61         0x25, 0x04,
  62         0x2e, 0x00,
  63         0x39, 0x00,
  64         0x3a, 0x04,
  65         0x45, 0x08,
  66         0x46, 0x02,
  67         0x47, 0x05,
  68 };
  69
  70
  71 static int cx22700_writereg (struct cx22700_state* state, u8 reg, u8 data)
  72 {
  73         int ret;
  74         u8 buf [] = { reg, data };
  75         struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf, .len = 2 };
  76
  77         dprintk ("%s\n", __FUNCTION__);
  78
  79         ret = i2c_transfer (state->i2c, &msg, 1);
  80
  81         if (ret != 1)
  82                 printk("%s: writereg error (reg == 0x%02x, val == 0x%02x, ret == %i)\n",
  83                         __FUNCTION__, reg, data, ret);
  84
  85         return (ret != 1) ? -1 : 0;
  86 }
  87
  88 static int cx22700_readreg (struct cx22700_state* state, u8 reg)
  89 {
  90         int ret;
  91         u8 b0 [] = { reg };
  92         u8 b1 [] = { 0 };
  93         struct i2c_msg msg [] = { { .addr = state->config->demod_address, .flags = 0, .buf = b0, .len = 1 },
  94                            { .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = b1, .len = 1 } };
  95
  96         dprintk ("%s\n", __FUNCTION__);
  97
  98         ret = i2c_transfer (state->i2c, msg, 2);
  99
 100         if (ret != 2) return -EIO;
 101
 102         return b1[0];
 103 }
 104
 105 static int cx22700_set_inversion (struct cx22700_state* state, int inversion)
 106 {
 107         u8 val;
 108
 109         dprintk ("%s\n", __FUNCTION__);
 110
 111         switch (inversion) {
 112         case INVERSION_AUTO:
 113                 return -EOPNOTSUPP;
 114         case INVERSION_ON:
 115                 val = cx22700_readreg (state, 0x09);
 116                 return cx22700_writereg (state, 0x09, val | 0x01);
 117         case INVERSION_OFF:
 118                 val = cx22700_readreg (state, 0x09);
 119                 return cx22700_writereg (state, 0x09, val & 0xfe);
 120         default:
 121                 return -EINVAL;
 122         }
 123 }
 124
 125 static int cx22700_set_tps (struct cx22700_state *state, struct dvb_ofdm_parameters *p)
 126 {
 127         static const u8 qam_tab [4] = { 0, 1, 0, 2 };
 128         static const u8 fec_tab [6] = { 0, 1, 2, 0, 3, 4 };
 129         u8 val;
 130
 131         dprintk ("%s\n", __FUNCTION__);
 132
 133         if (p->code_rate_HP < FEC_1_2 || p->code_rate_HP > FEC_7_8)
 134                 return -EINVAL;
 135
 136         if (p->code_rate_LP < FEC_1_2 || p->code_rate_LP > FEC_7_8)
 137                 return -EINVAL;
 138
 139         if (p->code_rate_HP == FEC_4_5 || p->code_rate_LP == FEC_4_5)
 140                 return -EINVAL;
 141
 142         if (p->guard_interval < GUARD_INTERVAL_1_32 ||
 143             p->guard_interval > GUARD_INTERVAL_1_4)
 144                 return -EINVAL;
 145
 146         if (p->transmission_mode != TRANSMISSION_MODE_2K &&
 147             p->transmission_mode != TRANSMISSION_MODE_8K)
 148                 return -EINVAL;
 149
 150         if (p->constellation != QPSK &&
 151             p->constellation != QAM_16 &&
 152             p->constellation != QAM_64)
 153                 return -EINVAL;
 154
 155         if (p->hierarchy_information < HIERARCHY_NONE ||
 156             p->hierarchy_information > HIERARCHY_4)
 157                 return -EINVAL;
 158
 159         if (p->bandwidth < BANDWIDTH_8_MHZ && p->bandwidth > BANDWIDTH_6_MHZ)
 160                 return -EINVAL;
 161
 162         if (p->bandwidth == BANDWIDTH_7_MHZ)
 163                 cx22700_writereg (state, 0x09, cx22700_readreg (state, 0x09 | 0x10));
 164         else
 165                 cx22700_writereg (state, 0x09, cx22700_readreg (state, 0x09 & ~0x10));
 166
 167         val = qam_tab[p->constellation - QPSK];
 168         val |= p->hierarchy_information - HIERARCHY_NONE;
 169
 170         cx22700_writereg (state, 0x04, val);
 171
 172         val = fec_tab[p->code_rate_HP - FEC_1_2] << 3;
 173         val |= fec_tab[p->code_rate_LP - FEC_1_2];
 174
 175         cx22700_writereg (state, 0x05, val);
 176
 177         val = (p->guard_interval - GUARD_INTERVAL_1_32) << 2;
 178         val |= p->transmission_mode - TRANSMISSION_MODE_2K;
 179
 180         cx22700_writereg (state, 0x06, val);
 181
 182         cx22700_writereg (state, 0x08, 0x04 | 0x02);  /* use user tps parameters */
 183         cx22700_writereg (state, 0x08, 0x04);         /* restart aquisition */
 184
 185         return 0;
 186 }
 187
 188 static int cx22700_get_tps (struct cx22700_state* state, struct dvb_ofdm_parameters *p)
 189 {
 190         static const fe_modulation_t qam_tab [3] = { QPSK, QAM_16, QAM_64 };
 191         static const fe_code_rate_t fec_tab [5] = { FEC_1_2, FEC_2_3, FEC_3_4,
 192                                                     FEC_5_6, FEC_7_8 };
 193         u8 val;
 194
 195         dprintk ("%s\n", __FUNCTION__);
 196
 197         if (!(cx22700_readreg(state, 0x07) & 0x20))  /*  tps valid? */
 198                 return -EAGAIN;
 199
 200         val = cx22700_readreg (state, 0x01);
 201
 202         if ((val & 0x7) > 4)
 203                 p->hierarchy_information = HIERARCHY_AUTO;
 204         else
 205                 p->hierarchy_information = HIERARCHY_NONE + (val & 0x7);
 206
 207         if (((val >> 3) & 0x3) > 2)
 208                 p->constellation = QAM_AUTO;
 209         else
 210                 p->constellation = qam_tab[(val >> 3) & 0x3];
 211
 212         val = cx22700_readreg (state, 0x02);
 213
 214         if (((val >> 3) & 0x07) > 4)
 215                 p->code_rate_HP = FEC_AUTO;
 216         else
 217                 p->code_rate_HP = fec_tab[(val >> 3) & 0x07];
 218
 219         if ((val & 0x07) > 4)
 220                 p->code_rate_LP = FEC_AUTO;
 221         else
 222                 p->code_rate_LP = fec_tab[val & 0x07];
 223
 224         val = cx22700_readreg (state, 0x03);
 225
 226         p->guard_interval = GUARD_INTERVAL_1_32 + ((val >> 6) & 0x3);
 227         p->transmission_mode = TRANSMISSION_MODE_2K + ((val >> 5) & 0x1);
 228
 229         return 0;
 230 }
 231
 232 static int cx22700_init (struct dvb_frontend* fe)
 233
 234 {       struct cx22700_state* state = fe->demodulator_priv;
 235         int i;
 236
 237         dprintk("cx22700_init: init chip\n");
 238
 239         cx22700_writereg (state, 0x00, 0x02);   /*  soft reset */
 240         cx22700_writereg (state, 0x00, 0x00);
 241
 242         msleep(10);
 243
 244         for (i=0; i<sizeof(init_tab); i+=2)
 245                 cx22700_writereg (state, init_tab[i], init_tab[i+1]);
 246
 247         cx22700_writereg (state, 0x00, 0x01);
 248
 249         return 0;
 250 }
 251
 252 static int cx22700_read_status(struct dvb_frontend* fe, fe_status_t* status)
 253 {
 254         struct cx22700_state* state = fe->demodulator_priv;
 255
 256         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 257                    | (cx22700_readreg (state, 0x0e) << 1);
 258         u8 sync = cx22700_readreg (state, 0x07);
 259
 260         *status = 0;
 261
 262         if (rs_ber < 0xff00)
 263                 *status |= FE_HAS_SIGNAL;
 264
 265         if (sync & 0x20)
 266                 *status |= FE_HAS_CARRIER;
 267
 268         if (sync & 0x10)
 269                 *status |= FE_HAS_VITERBI;
 270
 271         if (sync & 0x10)
 272                 *status |= FE_HAS_SYNC;
 273
 274         if (*status == 0x0f)
 275                 *status |= FE_HAS_LOCK;
 276
 277         return 0;
 278 }
 279
 280 static int cx22700_read_ber(struct dvb_frontend* fe, u32* ber)
 281 {
 282         struct cx22700_state* state = fe->demodulator_priv;
 283
 284         *ber = cx22700_readreg (state, 0x0c) & 0x7f;
 285         cx22700_writereg (state, 0x0c, 0x00);
 286
 287         return 0;
 288 }
 289
 290 static int cx22700_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
 291 {
 292         struct cx22700_state* state = fe->demodulator_priv;
 293
 294         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 295                    | (cx22700_readreg (state, 0x0e) << 1);
 296         *signal_strength = ~rs_ber;
 297
 298         return 0;
 299 }
 300
 301 static int cx22700_read_snr(struct dvb_frontend* fe, u16* snr)
 302 {
 303         struct cx22700_state* state = fe->demodulator_priv;
 304
 305         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 306                    | (cx22700_readreg (state, 0x0e) << 1);
 307         *snr = ~rs_ber;
 308
 309         return 0;
 310 }
 311
 312 static int cx22700_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
 313 {
 314         struct cx22700_state* state = fe->demodulator_priv;
 315
 316         *ucblocks = cx22700_readreg (state, 0x0f);
 317         cx22700_writereg (state, 0x0f, 0x00);
 318
 319         return 0;
 320 }
 321
 322 static int cx22700_set_frontend(struct dvb_frontend* fe, struct dvb_frontend_parameters *p)
 323 {
 324         struct cx22700_state* state = fe->demodulator_priv;
 325
 326         cx22700_writereg (state, 0x00, 0x02); /* XXX CHECKME: soft reset*/
 327         cx22700_writereg (state, 0x00, 0x00);
 328
 329         if (fe->ops.tuner_ops.set_params) {
 330                 fe->ops.tuner_ops.set_params(fe, p);
 331                 if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
 332         }
 333
 334         cx22700_set_inversion (state, p->inversion);
 335         cx22700_set_tps (state, &p->u.ofdm);
 336         cx22700_writereg (state, 0x37, 0x01);  /* PAL loop filter off */
 337         cx22700_writereg (state, 0x00, 0x01);  /* restart acquire */
 338
 339         return 0;
 340 }
 341
 342 static int cx22700_get_frontend(struct dvb_frontend* fe, struct dvb_frontend_parameters *p)
 343 {
 344         struct cx22700_state* state = fe->demodulator_priv;
 345         u8 reg09 = cx22700_readreg (state, 0x09);
 346
 347         p->inversion = reg09 & 0x1 ? INVERSION_ON : INVERSION_OFF;
 348         return cx22700_get_tps (state, &p->u.ofdm);
 349 }
 350
 351 static int cx22700_i2c_gate_ctrl(struct dvb_frontend* fe, int enable)
 352 {
 353         struct cx22700_state* state = fe->demodulator_priv;
 354
 355         if (enable) {
 356                 return cx22700_writereg(state, 0x0a, 0x00);
 357         } else {
 358                 return cx22700_writereg(state, 0x0a, 0x01);
 359         }
 360 }
 361
 362 static int cx22700_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fesettings)
 363 {
 364         fesettings->min_delay_ms = 150;
 365         fesettings->step_size = 166667;
 366         fesettings->max_drift = 166667*2;
 367         return 0;
 368 }
 369
 370 static void cx22700_release(struct dvb_frontend* fe)
 371 {
 372         struct cx22700_state* state = fe->demodulator_priv;
 373         kfree(state);
 374 }
 375
 376 static struct dvb_frontend_ops cx22700_ops;
 377
 378 struct dvb_frontend* cx22700_attach(const struct cx22700_config* config,
 379                                     struct i2c_adapter* i2c)
 380 {
 381         struct cx22700_state* state = NULL;
 382
 383         /* allocate memory for the internal state */
 384         state = kmalloc(sizeof(struct cx22700_state), GFP_KERNEL);
 385         if (state == NULL) goto error;
 386
 387         /* setup the state */
 388         state->config = config;
 389         state->i2c = i2c;
 390
 391         /* check if the demod is there */
 392         if (cx22700_readreg(state, 0x07) < 0) goto error;
 393
 394         /* create dvb_frontend */
 395         memcpy(&state->frontend.ops, &cx22700_ops, sizeof(struct dvb_frontend_ops));
 396         state->frontend.demodulator_priv = state;
 397         return &state->frontend;
 398
 399 error:
 400         kfree(state);
 401         return NULL;
 402 }
 403
 404 static struct dvb_frontend_ops cx22700_ops = {
 405
 406         .info = {
 407                 .name                   = "Conexant CX22700 DVB-T",
 408                 .type                   = FE_OFDM,
 409                 .frequency_min          = 470000000,
 410                 .frequency_max          = 860000000,
 411                 .frequency_stepsize     = 166667,
 412                 .caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
 413                       FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
 414                       FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 |
 415                       FE_CAN_RECOVER
 416         },
 417
 418         .release = cx22700_release,
 419
 420         .init = cx22700_init,
 421         .i2c_gate_ctrl = cx22700_i2c_gate_ctrl,
 422
 423         .set_frontend = cx22700_set_frontend,
 424         .get_frontend = cx22700_get_frontend,
 425         .get_tune_settings = cx22700_get_tune_settings,
 426
 427         .read_status = cx22700_read_status,
 428         .read_ber = cx22700_read_ber,
 429         .read_signal_strength = cx22700_read_signal_strength,
 430         .read_snr = cx22700_read_snr,
 431         .read_ucblocks = cx22700_read_ucblocks,
 432 };
 433
 434 module_param(debug, int, 0644);
 435 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
 436
 437 MODULE_DESCRIPTION("Conexant CX22700 DVB-T Demodulator driver");
 438 MODULE_AUTHOR("Holger Waechtler");
 439 MODULE_LICENSE("GPL");
 440
 441 EXPORT_SYMBOL(cx22700_attach);