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/string.h>
  27 #include <linux/slab.h>
  28 #include <media/dvb_frontend.h>
  29 #include "cx22700.h"
  30
  31
  32 struct cx22700_state {
  33
  34         struct i2c_adapter* i2c;
  35
  36         const struct cx22700_config* config;
  37
  38         struct dvb_frontend frontend;
  39 };
  40
  41
  42 static int debug;
  43 #define dprintk(args...) \
  44         do { \
  45                 if (debug) printk(KERN_DEBUG "cx22700: " args); \
  46         } while (0)
  47
  48 static u8 init_tab [] = {
  49         0x04, 0x10,
  50         0x05, 0x09,
  51         0x06, 0x00,
  52         0x08, 0x04,
  53         0x09, 0x00,
  54         0x0a, 0x01,
  55         0x15, 0x40,
  56         0x16, 0x10,
  57         0x17, 0x87,
  58         0x18, 0x17,
  59         0x1a, 0x10,
  60         0x25, 0x04,
  61         0x2e, 0x00,
  62         0x39, 0x00,
  63         0x3a, 0x04,
  64         0x45, 0x08,
  65         0x46, 0x02,
  66         0x47, 0x05,
  67 };
  68
  69
  70 static int cx22700_writereg (struct cx22700_state* state, u8 reg, u8 data)
  71 {
  72         int ret;
  73         u8 buf [] = { reg, data };
  74         struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf, .len = 2 };
  75
  76         dprintk ("%s\n", __func__);
  77
  78         ret = i2c_transfer (state->i2c, &msg, 1);
  79
  80         if (ret != 1)
  81                 printk("%s: writereg error (reg == 0x%02x, val == 0x%02x, ret == %i)\n",
  82                         __func__, reg, data, ret);
  83
  84         return (ret != 1) ? -1 : 0;
  85 }
  86
  87 static int cx22700_readreg (struct cx22700_state* state, u8 reg)
  88 {
  89         int ret;
  90         u8 b0 [] = { reg };
  91         u8 b1 [] = { 0 };
  92         struct i2c_msg msg [] = { { .addr = state->config->demod_address, .flags = 0, .buf = b0, .len = 1 },
  93                            { .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = b1, .len = 1 } };
  94
  95         dprintk ("%s\n", __func__);
  96
  97         ret = i2c_transfer (state->i2c, msg, 2);
  98
  99         if (ret != 2) return -EIO;
 100
 101         return b1[0];
 102 }
 103
 104 static int cx22700_set_inversion (struct cx22700_state* state, int inversion)
 105 {
 106         u8 val;
 107
 108         dprintk ("%s\n", __func__);
 109
 110         switch (inversion) {
 111         case INVERSION_AUTO:
 112                 return -EOPNOTSUPP;
 113         case INVERSION_ON:
 114                 val = cx22700_readreg (state, 0x09);
 115                 return cx22700_writereg (state, 0x09, val | 0x01);
 116         case INVERSION_OFF:
 117                 val = cx22700_readreg (state, 0x09);
 118                 return cx22700_writereg (state, 0x09, val & 0xfe);
 119         default:
 120                 return -EINVAL;
 121         }
 122 }
 123
 124 static int cx22700_set_tps(struct cx22700_state *state,
 125                            struct dtv_frontend_properties *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", __func__);
 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 ((int)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->modulation != QPSK &&
 151             p->modulation != QAM_16 &&
 152             p->modulation != QAM_64)
 153                 return -EINVAL;
 154
 155         if ((int)p->hierarchy < HIERARCHY_NONE ||
 156             p->hierarchy > HIERARCHY_4)
 157                 return -EINVAL;
 158
 159         if (p->bandwidth_hz > 8000000 || p->bandwidth_hz < 6000000)
 160                 return -EINVAL;
 161
 162         if (p->bandwidth_hz == 7000000)
 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->modulation - QPSK];
 168         val |= p->hierarchy - HIERARCHY_NONE;
 169
 170         cx22700_writereg (state, 0x04, val);
 171
 172         if (p->code_rate_HP - FEC_1_2 >= sizeof(fec_tab) ||
 173             p->code_rate_LP - FEC_1_2 >= sizeof(fec_tab))
 174                 return -EINVAL;
 175         val = fec_tab[p->code_rate_HP - FEC_1_2] << 3;
 176         val |= fec_tab[p->code_rate_LP - FEC_1_2];
 177
 178         cx22700_writereg (state, 0x05, val);
 179
 180         val = (p->guard_interval - GUARD_INTERVAL_1_32) << 2;
 181         val |= p->transmission_mode - TRANSMISSION_MODE_2K;
 182
 183         cx22700_writereg (state, 0x06, val);
 184
 185         cx22700_writereg (state, 0x08, 0x04 | 0x02);  /* use user tps parameters */
 186         cx22700_writereg (state, 0x08, 0x04);         /* restart acquisition */
 187
 188         return 0;
 189 }
 190
 191 static int cx22700_get_tps(struct cx22700_state *state,
 192                            struct dtv_frontend_properties *p)
 193 {
 194         static const enum fe_modulation qam_tab[3] = { QPSK, QAM_16, QAM_64 };
 195         static const enum fe_code_rate fec_tab[5] = {
 196                 FEC_1_2, FEC_2_3, FEC_3_4, FEC_5_6, FEC_7_8
 197         };
 198         u8 val;
 199
 200         dprintk ("%s\n", __func__);
 201
 202         if (!(cx22700_readreg(state, 0x07) & 0x20))  /*  tps valid? */
 203                 return -EAGAIN;
 204
 205         val = cx22700_readreg (state, 0x01);
 206
 207         if ((val & 0x7) > 4)
 208                 p->hierarchy = HIERARCHY_AUTO;
 209         else
 210                 p->hierarchy = HIERARCHY_NONE + (val & 0x7);
 211
 212         if (((val >> 3) & 0x3) > 2)
 213                 p->modulation = QAM_AUTO;
 214         else
 215                 p->modulation = qam_tab[(val >> 3) & 0x3];
 216
 217         val = cx22700_readreg (state, 0x02);
 218
 219         if (((val >> 3) & 0x07) > 4)
 220                 p->code_rate_HP = FEC_AUTO;
 221         else
 222                 p->code_rate_HP = fec_tab[(val >> 3) & 0x07];
 223
 224         if ((val & 0x07) > 4)
 225                 p->code_rate_LP = FEC_AUTO;
 226         else
 227                 p->code_rate_LP = fec_tab[val & 0x07];
 228
 229         val = cx22700_readreg (state, 0x03);
 230
 231         p->guard_interval = GUARD_INTERVAL_1_32 + ((val >> 6) & 0x3);
 232         p->transmission_mode = TRANSMISSION_MODE_2K + ((val >> 5) & 0x1);
 233
 234         return 0;
 235 }
 236
 237 static int cx22700_init (struct dvb_frontend* fe)
 238
 239 {       struct cx22700_state* state = fe->demodulator_priv;
 240         int i;
 241
 242         dprintk("cx22700_init: init chip\n");
 243
 244         cx22700_writereg (state, 0x00, 0x02);   /*  soft reset */
 245         cx22700_writereg (state, 0x00, 0x00);
 246
 247         msleep(10);
 248
 249         for (i=0; i<sizeof(init_tab); i+=2)
 250                 cx22700_writereg (state, init_tab[i], init_tab[i+1]);
 251
 252         cx22700_writereg (state, 0x00, 0x01);
 253
 254         return 0;
 255 }
 256
 257 static int cx22700_read_status(struct dvb_frontend *fe, enum fe_status *status)
 258 {
 259         struct cx22700_state* state = fe->demodulator_priv;
 260
 261         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 262                    | (cx22700_readreg (state, 0x0e) << 1);
 263         u8 sync = cx22700_readreg (state, 0x07);
 264
 265         *status = 0;
 266
 267         if (rs_ber < 0xff00)
 268                 *status |= FE_HAS_SIGNAL;
 269
 270         if (sync & 0x20)
 271                 *status |= FE_HAS_CARRIER;
 272
 273         if (sync & 0x10)
 274                 *status |= FE_HAS_VITERBI;
 275
 276         if (sync & 0x10)
 277                 *status |= FE_HAS_SYNC;
 278
 279         if (*status == 0x0f)
 280                 *status |= FE_HAS_LOCK;
 281
 282         return 0;
 283 }
 284
 285 static int cx22700_read_ber(struct dvb_frontend* fe, u32* ber)
 286 {
 287         struct cx22700_state* state = fe->demodulator_priv;
 288
 289         *ber = cx22700_readreg (state, 0x0c) & 0x7f;
 290         cx22700_writereg (state, 0x0c, 0x00);
 291
 292         return 0;
 293 }
 294
 295 static int cx22700_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
 296 {
 297         struct cx22700_state* state = fe->demodulator_priv;
 298
 299         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 300                    | (cx22700_readreg (state, 0x0e) << 1);
 301         *signal_strength = ~rs_ber;
 302
 303         return 0;
 304 }
 305
 306 static int cx22700_read_snr(struct dvb_frontend* fe, u16* snr)
 307 {
 308         struct cx22700_state* state = fe->demodulator_priv;
 309
 310         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 311                    | (cx22700_readreg (state, 0x0e) << 1);
 312         *snr = ~rs_ber;
 313
 314         return 0;
 315 }
 316
 317 static int cx22700_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
 318 {
 319         struct cx22700_state* state = fe->demodulator_priv;
 320
 321         *ucblocks = cx22700_readreg (state, 0x0f);
 322         cx22700_writereg (state, 0x0f, 0x00);
 323
 324         return 0;
 325 }
 326
 327 static int cx22700_set_frontend(struct dvb_frontend *fe)
 328 {
 329         struct dtv_frontend_properties *c = &fe->dtv_property_cache;
 330         struct cx22700_state* state = fe->demodulator_priv;
 331
 332         cx22700_writereg (state, 0x00, 0x02); /* XXX CHECKME: soft reset*/
 333         cx22700_writereg (state, 0x00, 0x00);
 334
 335         if (fe->ops.tuner_ops.set_params) {
 336                 fe->ops.tuner_ops.set_params(fe);
 337                 if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
 338         }
 339
 340         cx22700_set_inversion(state, c->inversion);
 341         cx22700_set_tps(state, c);
 342         cx22700_writereg (state, 0x37, 0x01);  /* PAL loop filter off */
 343         cx22700_writereg (state, 0x00, 0x01);  /* restart acquire */
 344
 345         return 0;
 346 }
 347
 348 static int cx22700_get_frontend(struct dvb_frontend *fe,
 349                                 struct dtv_frontend_properties *c)
 350 {
 351         struct cx22700_state* state = fe->demodulator_priv;
 352         u8 reg09 = cx22700_readreg (state, 0x09);
 353
 354         c->inversion = reg09 & 0x1 ? INVERSION_ON : INVERSION_OFF;
 355         return cx22700_get_tps(state, c);
 356 }
 357
 358 static int cx22700_i2c_gate_ctrl(struct dvb_frontend* fe, int enable)
 359 {
 360         struct cx22700_state* state = fe->demodulator_priv;
 361
 362         if (enable) {
 363                 return cx22700_writereg(state, 0x0a, 0x00);
 364         } else {
 365                 return cx22700_writereg(state, 0x0a, 0x01);
 366         }
 367 }
 368
 369 static int cx22700_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fesettings)
 370 {
 371         fesettings->min_delay_ms = 150;
 372         fesettings->step_size = 166667;
 373         fesettings->max_drift = 166667*2;
 374         return 0;
 375 }
 376
 377 static void cx22700_release(struct dvb_frontend* fe)
 378 {
 379         struct cx22700_state* state = fe->demodulator_priv;
 380         kfree(state);
 381 }
 382
 383 static const struct dvb_frontend_ops cx22700_ops;
 384
 385 struct dvb_frontend* cx22700_attach(const struct cx22700_config* config,
 386                                     struct i2c_adapter* i2c)
 387 {
 388         struct cx22700_state* state = NULL;
 389
 390         /* allocate memory for the internal state */
 391         state = kzalloc(sizeof(struct cx22700_state), GFP_KERNEL);
 392         if (state == NULL) goto error;
 393
 394         /* setup the state */
 395         state->config = config;
 396         state->i2c = i2c;
 397
 398         /* check if the demod is there */
 399         if (cx22700_readreg(state, 0x07) < 0) goto error;
 400
 401         /* create dvb_frontend */
 402         memcpy(&state->frontend.ops, &cx22700_ops, sizeof(struct dvb_frontend_ops));
 403         state->frontend.demodulator_priv = state;
 404         return &state->frontend;
 405
 406 error:
 407         kfree(state);
 408         return NULL;
 409 }
 410
 411 static const struct dvb_frontend_ops cx22700_ops = {
 412         .delsys = { SYS_DVBT },
 413         .info = {
 414                 .name                   = "Conexant CX22700 DVB-T",
 415                 .frequency_min          = 470000000,
 416                 .frequency_max          = 860000000,
 417                 .frequency_stepsize     = 166667,
 418                 .caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
 419                       FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
 420                       FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 |
 421                       FE_CAN_RECOVER
 422         },
 423
 424         .release = cx22700_release,
 425
 426         .init = cx22700_init,
 427         .i2c_gate_ctrl = cx22700_i2c_gate_ctrl,
 428
 429         .set_frontend = cx22700_set_frontend,
 430         .get_frontend = cx22700_get_frontend,
 431         .get_tune_settings = cx22700_get_tune_settings,
 432
 433         .read_status = cx22700_read_status,
 434         .read_ber = cx22700_read_ber,
 435         .read_signal_strength = cx22700_read_signal_strength,
 436         .read_snr = cx22700_read_snr,
 437         .read_ucblocks = cx22700_read_ucblocks,
 438 };
 439
 440 module_param(debug, int, 0644);
 441 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
 442
 443 MODULE_DESCRIPTION("Conexant CX22700 DVB-T Demodulator driver");
 444 MODULE_AUTHOR("Holger Waechtler");
 445 MODULE_LICENSE("GPL");
 446
 447 EXPORT_SYMBOL(cx22700_attach);