linux/drivers/media/dvb-frontends/cx22700.c
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   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
  32struct cx22700_state {
  33
  34        struct i2c_adapter* i2c;
  35
  36        const struct cx22700_config* config;
  37
  38        struct dvb_frontend frontend;
  39};
  40
  41
  42static int debug;
  43#define dprintk(args...) \
  44        do { \
  45                if (debug) printk(KERN_DEBUG "cx22700: " args); \
  46        } while (0)
  47
  48static 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
  70static 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
  87static 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
 104static 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
 124static 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
 191static 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
 237static 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
 257static 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
 285static 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
 295static 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
 306static 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
 317static 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
 327static 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
 348static 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
 358static 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
 369static 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
 377static void cx22700_release(struct dvb_frontend* fe)
 378{
 379        struct cx22700_state* state = fe->demodulator_priv;
 380        kfree(state);
 381}
 382
 383static const struct dvb_frontend_ops cx22700_ops;
 384
 385struct 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
 406error:
 407        kfree(state);
 408        return NULL;
 409}
 410
 411static 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
 440module_param(debug, int, 0644);
 441MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
 442
 443MODULE_DESCRIPTION("Conexant CX22700 DVB-T Demodulator driver");
 444MODULE_AUTHOR("Holger Waechtler");
 445MODULE_LICENSE("GPL");
 446
 447EXPORT_SYMBOL(cx22700_attach);
 448