drivers/media/dvb-frontends/cx22700.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3     Conexant cx22700 DVB OFDM demodulator driver
   4
   5     Copyright (C) 2001-2002 Convergence Integrated Media GmbH
   6         Holger Waechtler <holger@convergence.de>
   7
   8
   9 */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/module.h>
  14 #include <linux/string.h>
  15 #include <linux/slab.h>
  16 #include <media/dvb_frontend.h>
  17 #include "cx22700.h"
  18
  19
  20 struct cx22700_state {
  21
  22         struct i2c_adapter* i2c;
  23
  24         const struct cx22700_config* config;
  25
  26         struct dvb_frontend frontend;
  27 };
  28
  29
  30 static int debug;
  31 #define dprintk(args...) \
  32         do { \
  33                 if (debug) printk(KERN_DEBUG "cx22700: " args); \
  34         } while (0)
  35
  36 static u8 init_tab [] = {
  37         0x04, 0x10,
  38         0x05, 0x09,
  39         0x06, 0x00,
  40         0x08, 0x04,
  41         0x09, 0x00,
  42         0x0a, 0x01,
  43         0x15, 0x40,
  44         0x16, 0x10,
  45         0x17, 0x87,
  46         0x18, 0x17,
  47         0x1a, 0x10,
  48         0x25, 0x04,
  49         0x2e, 0x00,
  50         0x39, 0x00,
  51         0x3a, 0x04,
  52         0x45, 0x08,
  53         0x46, 0x02,
  54         0x47, 0x05,
  55 };
  56
  57
  58 static int cx22700_writereg (struct cx22700_state* state, u8 reg, u8 data)
  59 {
  60         int ret;
  61         u8 buf [] = { reg, data };
  62         struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf, .len = 2 };
  63
  64         dprintk ("%s\n", __func__);
  65
  66         ret = i2c_transfer (state->i2c, &msg, 1);
  67
  68         if (ret != 1)
  69                 printk("%s: writereg error (reg == 0x%02x, val == 0x%02x, ret == %i)\n",
  70                         __func__, reg, data, ret);
  71
  72         return (ret != 1) ? -1 : 0;
  73 }
  74
  75 static int cx22700_readreg (struct cx22700_state* state, u8 reg)
  76 {
  77         int ret;
  78         u8 b0 [] = { reg };
  79         u8 b1 [] = { 0 };
  80         struct i2c_msg msg [] = { { .addr = state->config->demod_address, .flags = 0, .buf = b0, .len = 1 },
  81                            { .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = b1, .len = 1 } };
  82
  83         dprintk ("%s\n", __func__);
  84
  85         ret = i2c_transfer (state->i2c, msg, 2);
  86
  87         if (ret != 2) return -EIO;
  88
  89         return b1[0];
  90 }
  91
  92 static int cx22700_set_inversion (struct cx22700_state* state, int inversion)
  93 {
  94         u8 val;
  95
  96         dprintk ("%s\n", __func__);
  97
  98         switch (inversion) {
  99         case INVERSION_AUTO:
 100                 return -EOPNOTSUPP;
 101         case INVERSION_ON:
 102                 val = cx22700_readreg (state, 0x09);
 103                 return cx22700_writereg (state, 0x09, val | 0x01);
 104         case INVERSION_OFF:
 105                 val = cx22700_readreg (state, 0x09);
 106                 return cx22700_writereg (state, 0x09, val & 0xfe);
 107         default:
 108                 return -EINVAL;
 109         }
 110 }
 111
 112 static int cx22700_set_tps(struct cx22700_state *state,
 113                            struct dtv_frontend_properties *p)
 114 {
 115         static const u8 qam_tab [4] = { 0, 1, 0, 2 };
 116         static const u8 fec_tab [6] = { 0, 1, 2, 0, 3, 4 };
 117         u8 val;
 118
 119         dprintk ("%s\n", __func__);
 120
 121         if (p->code_rate_HP < FEC_1_2 || p->code_rate_HP > FEC_7_8)
 122                 return -EINVAL;
 123
 124         if (p->code_rate_LP < FEC_1_2 || p->code_rate_LP > FEC_7_8)
 125                 return -EINVAL;
 126
 127         if (p->code_rate_HP == FEC_4_5 || p->code_rate_LP == FEC_4_5)
 128                 return -EINVAL;
 129
 130         if ((int)p->guard_interval < GUARD_INTERVAL_1_32 ||
 131             p->guard_interval > GUARD_INTERVAL_1_4)
 132                 return -EINVAL;
 133
 134         if (p->transmission_mode != TRANSMISSION_MODE_2K &&
 135             p->transmission_mode != TRANSMISSION_MODE_8K)
 136                 return -EINVAL;
 137
 138         if (p->modulation != QPSK &&
 139             p->modulation != QAM_16 &&
 140             p->modulation != QAM_64)
 141                 return -EINVAL;
 142
 143         if ((int)p->hierarchy < HIERARCHY_NONE ||
 144             p->hierarchy > HIERARCHY_4)
 145                 return -EINVAL;
 146
 147         if (p->bandwidth_hz > 8000000 || p->bandwidth_hz < 6000000)
 148                 return -EINVAL;
 149
 150         if (p->bandwidth_hz == 7000000)
 151                 cx22700_writereg (state, 0x09, cx22700_readreg (state, 0x09 | 0x10));
 152         else
 153                 cx22700_writereg (state, 0x09, cx22700_readreg (state, 0x09 & ~0x10));
 154
 155         val = qam_tab[p->modulation - QPSK];
 156         val |= p->hierarchy - HIERARCHY_NONE;
 157
 158         cx22700_writereg (state, 0x04, val);
 159
 160         if (p->code_rate_HP - FEC_1_2 >= sizeof(fec_tab) ||
 161             p->code_rate_LP - FEC_1_2 >= sizeof(fec_tab))
 162                 return -EINVAL;
 163         val = fec_tab[p->code_rate_HP - FEC_1_2] << 3;
 164         val |= fec_tab[p->code_rate_LP - FEC_1_2];
 165
 166         cx22700_writereg (state, 0x05, val);
 167
 168         val = (p->guard_interval - GUARD_INTERVAL_1_32) << 2;
 169         val |= p->transmission_mode - TRANSMISSION_MODE_2K;
 170
 171         cx22700_writereg (state, 0x06, val);
 172
 173         cx22700_writereg (state, 0x08, 0x04 | 0x02);  /* use user tps parameters */
 174         cx22700_writereg (state, 0x08, 0x04);         /* restart acquisition */
 175
 176         return 0;
 177 }
 178
 179 static int cx22700_get_tps(struct cx22700_state *state,
 180                            struct dtv_frontend_properties *p)
 181 {
 182         static const enum fe_modulation qam_tab[3] = { QPSK, QAM_16, QAM_64 };
 183         static const enum fe_code_rate fec_tab[5] = {
 184                 FEC_1_2, FEC_2_3, FEC_3_4, FEC_5_6, FEC_7_8
 185         };
 186         u8 val;
 187
 188         dprintk ("%s\n", __func__);
 189
 190         if (!(cx22700_readreg(state, 0x07) & 0x20))  /*  tps valid? */
 191                 return -EAGAIN;
 192
 193         val = cx22700_readreg (state, 0x01);
 194
 195         if ((val & 0x7) > 4)
 196                 p->hierarchy = HIERARCHY_AUTO;
 197         else
 198                 p->hierarchy = HIERARCHY_NONE + (val & 0x7);
 199
 200         if (((val >> 3) & 0x3) > 2)
 201                 p->modulation = QAM_AUTO;
 202         else
 203                 p->modulation = qam_tab[(val >> 3) & 0x3];
 204
 205         val = cx22700_readreg (state, 0x02);
 206
 207         if (((val >> 3) & 0x07) > 4)
 208                 p->code_rate_HP = FEC_AUTO;
 209         else
 210                 p->code_rate_HP = fec_tab[(val >> 3) & 0x07];
 211
 212         if ((val & 0x07) > 4)
 213                 p->code_rate_LP = FEC_AUTO;
 214         else
 215                 p->code_rate_LP = fec_tab[val & 0x07];
 216
 217         val = cx22700_readreg (state, 0x03);
 218
 219         p->guard_interval = GUARD_INTERVAL_1_32 + ((val >> 6) & 0x3);
 220         p->transmission_mode = TRANSMISSION_MODE_2K + ((val >> 5) & 0x1);
 221
 222         return 0;
 223 }
 224
 225 static int cx22700_init (struct dvb_frontend* fe)
 226
 227 {       struct cx22700_state* state = fe->demodulator_priv;
 228         int i;
 229
 230         dprintk("cx22700_init: init chip\n");
 231
 232         cx22700_writereg (state, 0x00, 0x02);   /*  soft reset */
 233         cx22700_writereg (state, 0x00, 0x00);
 234
 235         msleep(10);
 236
 237         for (i=0; i<sizeof(init_tab); i+=2)
 238                 cx22700_writereg (state, init_tab[i], init_tab[i+1]);
 239
 240         cx22700_writereg (state, 0x00, 0x01);
 241
 242         return 0;
 243 }
 244
 245 static int cx22700_read_status(struct dvb_frontend *fe, enum fe_status *status)
 246 {
 247         struct cx22700_state* state = fe->demodulator_priv;
 248
 249         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 250                    | (cx22700_readreg (state, 0x0e) << 1);
 251         u8 sync = cx22700_readreg (state, 0x07);
 252
 253         *status = 0;
 254
 255         if (rs_ber < 0xff00)
 256                 *status |= FE_HAS_SIGNAL;
 257
 258         if (sync & 0x20)
 259                 *status |= FE_HAS_CARRIER;
 260
 261         if (sync & 0x10)
 262                 *status |= FE_HAS_VITERBI;
 263
 264         if (sync & 0x10)
 265                 *status |= FE_HAS_SYNC;
 266
 267         if (*status == 0x0f)
 268                 *status |= FE_HAS_LOCK;
 269
 270         return 0;
 271 }
 272
 273 static int cx22700_read_ber(struct dvb_frontend* fe, u32* ber)
 274 {
 275         struct cx22700_state* state = fe->demodulator_priv;
 276
 277         *ber = cx22700_readreg (state, 0x0c) & 0x7f;
 278         cx22700_writereg (state, 0x0c, 0x00);
 279
 280         return 0;
 281 }
 282
 283 static int cx22700_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
 284 {
 285         struct cx22700_state* state = fe->demodulator_priv;
 286
 287         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 288                    | (cx22700_readreg (state, 0x0e) << 1);
 289         *signal_strength = ~rs_ber;
 290
 291         return 0;
 292 }
 293
 294 static int cx22700_read_snr(struct dvb_frontend* fe, u16* snr)
 295 {
 296         struct cx22700_state* state = fe->demodulator_priv;
 297
 298         u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
 299                    | (cx22700_readreg (state, 0x0e) << 1);
 300         *snr = ~rs_ber;
 301
 302         return 0;
 303 }
 304
 305 static int cx22700_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
 306 {
 307         struct cx22700_state* state = fe->demodulator_priv;
 308
 309         *ucblocks = cx22700_readreg (state, 0x0f);
 310         cx22700_writereg (state, 0x0f, 0x00);
 311
 312         return 0;
 313 }
 314
 315 static int cx22700_set_frontend(struct dvb_frontend *fe)
 316 {
 317         struct dtv_frontend_properties *c = &fe->dtv_property_cache;
 318         struct cx22700_state* state = fe->demodulator_priv;
 319
 320         cx22700_writereg (state, 0x00, 0x02); /* XXX CHECKME: soft reset*/
 321         cx22700_writereg (state, 0x00, 0x00);
 322
 323         if (fe->ops.tuner_ops.set_params) {
 324                 fe->ops.tuner_ops.set_params(fe);
 325                 if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
 326         }
 327
 328         cx22700_set_inversion(state, c->inversion);
 329         cx22700_set_tps(state, c);
 330         cx22700_writereg (state, 0x37, 0x01);  /* PAL loop filter off */
 331         cx22700_writereg (state, 0x00, 0x01);  /* restart acquire */
 332
 333         return 0;
 334 }
 335
 336 static int cx22700_get_frontend(struct dvb_frontend *fe,
 337                                 struct dtv_frontend_properties *c)
 338 {
 339         struct cx22700_state* state = fe->demodulator_priv;
 340         u8 reg09 = cx22700_readreg (state, 0x09);
 341
 342         c->inversion = reg09 & 0x1 ? INVERSION_ON : INVERSION_OFF;
 343         return cx22700_get_tps(state, c);
 344 }
 345
 346 static int cx22700_i2c_gate_ctrl(struct dvb_frontend* fe, int enable)
 347 {
 348         struct cx22700_state* state = fe->demodulator_priv;
 349
 350         if (enable) {
 351                 return cx22700_writereg(state, 0x0a, 0x00);
 352         } else {
 353                 return cx22700_writereg(state, 0x0a, 0x01);
 354         }
 355 }
 356
 357 static int cx22700_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fesettings)
 358 {
 359         fesettings->min_delay_ms = 150;
 360         fesettings->step_size = 166667;
 361         fesettings->max_drift = 166667*2;
 362         return 0;
 363 }
 364
 365 static void cx22700_release(struct dvb_frontend* fe)
 366 {
 367         struct cx22700_state* state = fe->demodulator_priv;
 368         kfree(state);
 369 }
 370
 371 static const struct dvb_frontend_ops cx22700_ops;
 372
 373 struct dvb_frontend* cx22700_attach(const struct cx22700_config* config,
 374                                     struct i2c_adapter* i2c)
 375 {
 376         struct cx22700_state* state = NULL;
 377
 378         /* allocate memory for the internal state */
 379         state = kzalloc(sizeof(struct cx22700_state), GFP_KERNEL);
 380         if (state == NULL) goto error;
 381
 382         /* setup the state */
 383         state->config = config;
 384         state->i2c = i2c;
 385
 386         /* check if the demod is there */
 387         if (cx22700_readreg(state, 0x07) < 0) goto error;
 388
 389         /* create dvb_frontend */
 390         memcpy(&state->frontend.ops, &cx22700_ops, sizeof(struct dvb_frontend_ops));
 391         state->frontend.demodulator_priv = state;
 392         return &state->frontend;
 393
 394 error:
 395         kfree(state);
 396         return NULL;
 397 }
 398
 399 static const struct dvb_frontend_ops cx22700_ops = {
 400         .delsys = { SYS_DVBT },
 401         .info = {
 402                 .name                   = "Conexant CX22700 DVB-T",
 403                 .frequency_min_hz       = 470 * MHz,
 404                 .frequency_max_hz       = 860 * MHz,
 405                 .frequency_stepsize_hz  = 166667,
 406                 .caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
 407                       FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
 408                       FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 |
 409                       FE_CAN_RECOVER
 410         },
 411
 412         .release = cx22700_release,
 413
 414         .init = cx22700_init,
 415         .i2c_gate_ctrl = cx22700_i2c_gate_ctrl,
 416
 417         .set_frontend = cx22700_set_frontend,
 418         .get_frontend = cx22700_get_frontend,
 419         .get_tune_settings = cx22700_get_tune_settings,
 420
 421         .read_status = cx22700_read_status,
 422         .read_ber = cx22700_read_ber,
 423         .read_signal_strength = cx22700_read_signal_strength,
 424         .read_snr = cx22700_read_snr,
 425         .read_ucblocks = cx22700_read_ucblocks,
 426 };
 427
 428 module_param(debug, int, 0644);
 429 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
 430
 431 MODULE_DESCRIPTION("Conexant CX22700 DVB-T Demodulator driver");
 432 MODULE_AUTHOR("Holger Waechtler");
 433 MODULE_LICENSE("GPL");
 434
 435 EXPORT_SYMBOL(cx22700_attach);