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 "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, struct dvb_ofdm_parameters *p)
 125 {
 126         static const u8 qam_tab [4] = { 0, 1, 0, 2 };
 127         static const u8 fec_tab [6] = { 0, 1, 2, 0, 3, 4 };
 128         u8 val;
 129
 130         dprintk ("%s\n", __func__);
 131
 132         if (p->code_rate_HP < FEC_1_2 || p->code_rate_HP > FEC_7_8)
 133                 return -EINVAL;
 134
 135         if (p->code_rate_LP < FEC_1_2 || p->code_rate_LP > FEC_7_8)
 136                 return -EINVAL;
 137
 138         if (p->code_rate_HP == FEC_4_5 || p->code_rate_LP == FEC_4_5)
 139                 return -EINVAL;
 140
 141         if (p->guard_interval < GUARD_INTERVAL_1_32 ||
 142             p->guard_interval > GUARD_INTERVAL_1_4)
 143                 return -EINVAL;
 144
 145         if (p->transmission_mode != TRANSMISSION_MODE_2K &&
 146             p->transmission_mode != TRANSMISSION_MODE_8K)
 147                 return -EINVAL;
 148
 149         if (p->constellation != QPSK &&
 150             p->constellation != QAM_16 &&
 151             p->constellation != QAM_64)
 152                 return -EINVAL;
 153
 154         if (p->hierarchy_information < HIERARCHY_NONE ||
 155             p->hierarchy_information > HIERARCHY_4)
 156                 return -EINVAL;
 157
 158         if (p->bandwidth < BANDWIDTH_8_MHZ || p->bandwidth > BANDWIDTH_6_MHZ)
 159                 return -EINVAL;
 160
 161         if (p->bandwidth == BANDWIDTH_7_MHZ)
 162                 cx22700_writereg (state, 0x09, cx22700_readreg (state, 0x09 | 0x10));
 163         else
 164                 cx22700_writereg (state, 0x09, cx22700_readreg (state, 0x09 & ~0x10));
 165
 166         val = qam_tab[p->constellation - QPSK];
 167         val |= p->hierarchy_information - HIERARCHY_NONE;
 168
 169         cx22700_writereg (state, 0x04, val);
 170
 171         val = fec_tab[p->code_rate_HP - FEC_1_2] << 3;
 172         val |= fec_tab[p->code_rate_LP - FEC_1_2];
 173
 174         cx22700_writereg (state, 0x05, val);
 175
 176         val = (p->guard_interval - GUARD_INTERVAL_1_32) << 2;
 177         val |= p->transmission_mode - TRANSMISSION_MODE_2K;
 178
 179         cx22700_writereg (state, 0x06, val);
 180
 181         cx22700_writereg (state, 0x08, 0x04 | 0x02);  /* use user tps parameters */
 182         cx22700_writereg (state, 0x08, 0x04);         /* restart aquisition */
 183
 184         return 0;
 185 }
 186
 187 static int cx22700_get_tps (struct cx22700_state* state, struct dvb_ofdm_parameters *p)
 188 {
 189         static const fe_modulation_t qam_tab [3] = { QPSK, QAM_16, QAM_64 };
 190         static const fe_code_rate_t fec_tab [5] = { FEC_1_2, FEC_2_3, FEC_3_4,
 191                                                     FEC_5_6, FEC_7_8 };
 192         u8 val;
 193
 194         dprintk ("%s\n", __func__);
 195
 196         if (!(cx22700_readreg(state, 0x07) & 0x20))  /*  tps valid? */
 197                 return -EAGAIN;
 198
 199         val = cx22700_readreg (state, 0x01);
 200
 201         if ((val & 0x7) > 4)
 202                 p->hierarchy_information = HIERARCHY_AUTO;
 203         else
 204                 p->hierarchy_information = HIERARCHY_NONE + (val & 0x7);
 205
 206         if (((val >> 3) & 0x3) > 2)
 207                 p->constellation = QAM_AUTO;
 208         else
 209                 p->constellation = qam_tab[(val >> 3) & 0x3];
 210
 211         val = cx22700_readreg (state, 0x02);
 212
 213         if (((val >> 3) & 0x07) > 4)
 214                 p->code_rate_HP = FEC_AUTO;
 215         else
 216                 p->code_rate_HP = fec_tab[(val >> 3) & 0x07];
 217
 218         if ((val & 0x07) > 4)
 219                 p->code_rate_LP = FEC_AUTO;
 220         else
 221                 p->code_rate_LP = fec_tab[val & 0x07];
 222
 223         val = cx22700_readreg (state, 0x03);
 224
 225         p->guard_interval = GUARD_INTERVAL_1_32 + ((val >> 6) & 0x3);
 226         p->transmission_mode = TRANSMISSION_MODE_2K + ((val >> 5) & 0x1);
 227
 228         return 0;
 229 }
 230
 231 static int cx22700_init (struct dvb_frontend* fe)
 232
 233 {       struct cx22700_state* state = fe->demodulator_priv;
 234         int i;
 235
 236         dprintk("cx22700_init: init chip\n");
 237
 238         cx22700_writereg (state, 0x00, 0x02);   /*  soft reset */
 239         cx22700_writereg (state, 0x00, 0x00);
 240
 241         msleep(10);
 242
 243         for (i=0; i<sizeof(init_tab); i+=2)
 244                 cx22700_writereg (state, init_tab[i], init_tab[i+1]);
 245
 246         cx22700_writereg (state, 0x00, 0x01);
 247
 248         return 0;
 249 }
 250
 251 static int cx22700_read_status(struct dvb_frontend* fe, fe_status_t* status)
 252 {
 253         struct cx22700_state* state = fe->demodulator_priv;
 254
 255         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 256                    | (cx22700_readreg (state, 0x0e) << 1);
 257         u8 sync = cx22700_readreg (state, 0x07);
 258
 259         *status = 0;
 260
 261         if (rs_ber < 0xff00)
 262                 *status |= FE_HAS_SIGNAL;
 263
 264         if (sync & 0x20)
 265                 *status |= FE_HAS_CARRIER;
 266
 267         if (sync & 0x10)
 268                 *status |= FE_HAS_VITERBI;
 269
 270         if (sync & 0x10)
 271                 *status |= FE_HAS_SYNC;
 272
 273         if (*status == 0x0f)
 274                 *status |= FE_HAS_LOCK;
 275
 276         return 0;
 277 }
 278
 279 static int cx22700_read_ber(struct dvb_frontend* fe, u32* ber)
 280 {
 281         struct cx22700_state* state = fe->demodulator_priv;
 282
 283         *ber = cx22700_readreg (state, 0x0c) & 0x7f;
 284         cx22700_writereg (state, 0x0c, 0x00);
 285
 286         return 0;
 287 }
 288
 289 static int cx22700_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
 290 {
 291         struct cx22700_state* state = fe->demodulator_priv;
 292
 293         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 294                    | (cx22700_readreg (state, 0x0e) << 1);
 295         *signal_strength = ~rs_ber;
 296
 297         return 0;
 298 }
 299
 300 static int cx22700_read_snr(struct dvb_frontend* fe, u16* snr)
 301 {
 302         struct cx22700_state* state = fe->demodulator_priv;
 303
 304         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 305                    | (cx22700_readreg (state, 0x0e) << 1);
 306         *snr = ~rs_ber;
 307
 308         return 0;
 309 }
 310
 311 static int cx22700_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
 312 {
 313         struct cx22700_state* state = fe->demodulator_priv;
 314
 315         *ucblocks = cx22700_readreg (state, 0x0f);
 316         cx22700_writereg (state, 0x0f, 0x00);
 317
 318         return 0;
 319 }
 320
 321 static int cx22700_set_frontend(struct dvb_frontend* fe, struct dvb_frontend_parameters *p)
 322 {
 323         struct cx22700_state* state = fe->demodulator_priv;
 324
 325         cx22700_writereg (state, 0x00, 0x02); /* XXX CHECKME: soft reset*/
 326         cx22700_writereg (state, 0x00, 0x00);
 327
 328         if (fe->ops.tuner_ops.set_params) {
 329                 fe->ops.tuner_ops.set_params(fe, p);
 330                 if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
 331         }
 332
 333         cx22700_set_inversion (state, p->inversion);
 334         cx22700_set_tps (state, &p->u.ofdm);
 335         cx22700_writereg (state, 0x37, 0x01);  /* PAL loop filter off */
 336         cx22700_writereg (state, 0x00, 0x01);  /* restart acquire */
 337
 338         return 0;
 339 }
 340
 341 static int cx22700_get_frontend(struct dvb_frontend* fe, struct dvb_frontend_parameters *p)
 342 {
 343         struct cx22700_state* state = fe->demodulator_priv;
 344         u8 reg09 = cx22700_readreg (state, 0x09);
 345
 346         p->inversion = reg09 & 0x1 ? INVERSION_ON : INVERSION_OFF;
 347         return cx22700_get_tps (state, &p->u.ofdm);
 348 }
 349
 350 static int cx22700_i2c_gate_ctrl(struct dvb_frontend* fe, int enable)
 351 {
 352         struct cx22700_state* state = fe->demodulator_priv;
 353
 354         if (enable) {
 355                 return cx22700_writereg(state, 0x0a, 0x00);
 356         } else {
 357                 return cx22700_writereg(state, 0x0a, 0x01);
 358         }
 359 }
 360
 361 static int cx22700_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fesettings)
 362 {
 363         fesettings->min_delay_ms = 150;
 364         fesettings->step_size = 166667;
 365         fesettings->max_drift = 166667*2;
 366         return 0;
 367 }
 368
 369 static void cx22700_release(struct dvb_frontend* fe)
 370 {
 371         struct cx22700_state* state = fe->demodulator_priv;
 372         kfree(state);
 373 }
 374
 375 static struct dvb_frontend_ops cx22700_ops;
 376
 377 struct dvb_frontend* cx22700_attach(const struct cx22700_config* config,
 378                                     struct i2c_adapter* i2c)
 379 {
 380         struct cx22700_state* state = NULL;
 381
 382         /* allocate memory for the internal state */
 383         state = kzalloc(sizeof(struct cx22700_state), GFP_KERNEL);
 384         if (state == NULL) goto error;
 385
 386         /* setup the state */
 387         state->config = config;
 388         state->i2c = i2c;
 389
 390         /* check if the demod is there */
 391         if (cx22700_readreg(state, 0x07) < 0) goto error;
 392
 393         /* create dvb_frontend */
 394         memcpy(&state->frontend.ops, &cx22700_ops, sizeof(struct dvb_frontend_ops));
 395         state->frontend.demodulator_priv = state;
 396         return &state->frontend;
 397
 398 error:
 399         kfree(state);
 400         return NULL;
 401 }
 402
 403 static struct dvb_frontend_ops cx22700_ops = {
 404
 405         .info = {
 406                 .name                   = "Conexant CX22700 DVB-T",
 407                 .type                   = FE_OFDM,
 408                 .frequency_min          = 470000000,
 409                 .frequency_max          = 860000000,
 410                 .frequency_stepsize     = 166667,
 411                 .caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
 412                       FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
 413                       FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 |
 414                       FE_CAN_RECOVER
 415         },
 416
 417         .release = cx22700_release,
 418
 419         .init = cx22700_init,
 420         .i2c_gate_ctrl = cx22700_i2c_gate_ctrl,
 421
 422         .set_frontend = cx22700_set_frontend,
 423         .get_frontend = cx22700_get_frontend,
 424         .get_tune_settings = cx22700_get_tune_settings,
 425
 426         .read_status = cx22700_read_status,
 427         .read_ber = cx22700_read_ber,
 428         .read_signal_strength = cx22700_read_signal_strength,
 429         .read_snr = cx22700_read_snr,
 430         .read_ucblocks = cx22700_read_ucblocks,
 431 };
 432
 433 module_param(debug, int, 0644);
 434 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
 435
 436 MODULE_DESCRIPTION("Conexant CX22700 DVB-T Demodulator driver");
 437 MODULE_AUTHOR("Holger Waechtler");
 438 MODULE_LICENSE("GPL");
 439
 440 EXPORT_SYMBOL(cx22700_attach);