Free Electrons

Embedded Linux Experts

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
/*
	NxtWave Communications - NXT6000 demodulator driver

    Copyright (C) 2002-2003 Florian Schirmer <jolt@tuxbox.org>
    Copyright (C) 2003 Paul Andreassen <paul@andreassen.com.au>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/slab.h>

#include "dvb_frontend.h"
#include "nxt6000_priv.h"
#include "nxt6000.h"



struct nxt6000_state {
	struct i2c_adapter* i2c;
	struct dvb_frontend_ops ops;
	/* configuration settings */
	const struct nxt6000_config* config;
	struct dvb_frontend frontend;
};

static int debug = 0;
#define dprintk if (debug) printk

static int nxt6000_writereg(struct nxt6000_state* state, u8 reg, u8 data)
{
	u8 buf[] = { reg, data };
	struct i2c_msg msg = {.addr = state->config->demod_address,.flags = 0,.buf = buf,.len = 2 };
	int ret;

	if ((ret = i2c_transfer(state->i2c, &msg, 1)) != 1)
		dprintk("nxt6000: nxt6000_write error (reg: 0x%02X, data: 0x%02X, ret: %d)\n", reg, data, ret);

	return (ret != 1) ? -EFAULT : 0;
}

static u8 nxt6000_readreg(struct nxt6000_state* state, u8 reg)
{
	int ret;
	u8 b0[] = { reg };
	u8 b1[] = { 0 };
	struct i2c_msg msgs[] = {
		{.addr = state->config->demod_address,.flags = 0,.buf = b0,.len = 1},
		{.addr = state->config->demod_address,.flags = I2C_M_RD,.buf = b1,.len = 1}
	};

	ret = i2c_transfer(state->i2c, msgs, 2);

	if (ret != 2)
		dprintk("nxt6000: nxt6000_read error (reg: 0x%02X, ret: %d)\n", reg, ret);

	return b1[0];
}

static void nxt6000_reset(struct nxt6000_state* state)
{
	u8 val;

	val = nxt6000_readreg(state, OFDM_COR_CTL);

	nxt6000_writereg(state, OFDM_COR_CTL, val & ~COREACT);
	nxt6000_writereg(state, OFDM_COR_CTL, val | COREACT);
}

static int nxt6000_set_bandwidth(struct nxt6000_state* state, fe_bandwidth_t bandwidth)
{
	u16 nominal_rate;
	int result;

	switch (bandwidth) {

	case BANDWIDTH_6_MHZ:
		nominal_rate = 0x55B7;
		break;

	case BANDWIDTH_7_MHZ:
		nominal_rate = 0x6400;
		break;

	case BANDWIDTH_8_MHZ:
		nominal_rate = 0x7249;
		break;

	default:
		return -EINVAL;
	}

	if ((result = nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_1, nominal_rate & 0xFF)) < 0)
		return result;

	return nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_2, (nominal_rate >> 8) & 0xFF);
}

static int nxt6000_set_guard_interval(struct nxt6000_state* state, fe_guard_interval_t guard_interval)
{
	switch (guard_interval) {

	case GUARD_INTERVAL_1_32:
		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x00 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

	case GUARD_INTERVAL_1_16:
		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x01 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

	case GUARD_INTERVAL_AUTO:
	case GUARD_INTERVAL_1_8:
		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x02 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

	case GUARD_INTERVAL_1_4:
		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, 0x03 | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x03));

	default:
		return -EINVAL;
	}
}

static int nxt6000_set_inversion(struct nxt6000_state* state, fe_spectral_inversion_t inversion)
{
	switch (inversion) {

	case INVERSION_OFF:
		return nxt6000_writereg(state, OFDM_ITB_CTL, 0x00);

	case INVERSION_ON:
		return nxt6000_writereg(state, OFDM_ITB_CTL, ITBINV);

	default:
		return -EINVAL;

	}
}

static int nxt6000_set_transmission_mode(struct nxt6000_state* state, fe_transmit_mode_t transmission_mode)
{
	int result;

	switch (transmission_mode) {

	case TRANSMISSION_MODE_2K:
		if ((result = nxt6000_writereg(state, EN_DMD_RACQ, 0x00 | (nxt6000_readreg(state, EN_DMD_RACQ) & ~0x03))) < 0)
			return result;

		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, (0x00 << 2) | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x04));

	case TRANSMISSION_MODE_8K:
	case TRANSMISSION_MODE_AUTO:
		if ((result = nxt6000_writereg(state, EN_DMD_RACQ, 0x02 | (nxt6000_readreg(state, EN_DMD_RACQ) & ~0x03))) < 0)
			return result;

		return nxt6000_writereg(state, OFDM_COR_MODEGUARD, (0x01 << 2) | (nxt6000_readreg(state, OFDM_COR_MODEGUARD) & ~0x04));

	default:
		return -EINVAL;

	}
}

static void nxt6000_setup(struct dvb_frontend* fe)
{
	struct nxt6000_state* state = fe->demodulator_priv;

	nxt6000_writereg(state, RS_COR_SYNC_PARAM, SYNC_PARAM);
	nxt6000_writereg(state, BER_CTRL, /*(1 << 2) | */ (0x01 << 1) | 0x01);
	nxt6000_writereg(state, VIT_BERTIME_2, 0x00);  // BER Timer = 0x000200 * 256 = 131072 bits
	nxt6000_writereg(state, VIT_BERTIME_1, 0x02);  //
	nxt6000_writereg(state, VIT_BERTIME_0, 0x00);  //
	nxt6000_writereg(state, VIT_COR_INTEN, 0x98); // Enable BER interrupts
	nxt6000_writereg(state, VIT_COR_CTL, 0x82);   // Enable BER measurement
	nxt6000_writereg(state, VIT_COR_CTL, VIT_COR_RESYNC | 0x02 );
	nxt6000_writereg(state, OFDM_COR_CTL, (0x01 << 5) | (nxt6000_readreg(state, OFDM_COR_CTL) & 0x0F));
	nxt6000_writereg(state, OFDM_COR_MODEGUARD, FORCEMODE8K | 0x02);
	nxt6000_writereg(state, OFDM_AGC_CTL, AGCLAST | INITIAL_AGC_BW);
	nxt6000_writereg(state, OFDM_ITB_FREQ_1, 0x06);
	nxt6000_writereg(state, OFDM_ITB_FREQ_2, 0x31);
	nxt6000_writereg(state, OFDM_CAS_CTL, (0x01 << 7) | (0x02 << 3) | 0x04);
	nxt6000_writereg(state, CAS_FREQ, 0xBB);	/* CHECKME */
	nxt6000_writereg(state, OFDM_SYR_CTL, 1 << 2);
	nxt6000_writereg(state, OFDM_PPM_CTL_1, PPM256);
	nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_1, 0x49);
	nxt6000_writereg(state, OFDM_TRL_NOMINALRATE_2, 0x72);
	nxt6000_writereg(state, ANALOG_CONTROL_0, 1 << 5);
	nxt6000_writereg(state, EN_DMD_RACQ, (1 << 7) | (3 << 4) | 2);
	nxt6000_writereg(state, DIAG_CONFIG, TB_SET);

	if (state->config->clock_inversion)
		nxt6000_writereg(state, SUB_DIAG_MODE_SEL, CLKINVERSION);
	else
		nxt6000_writereg(state, SUB_DIAG_MODE_SEL, 0);

	nxt6000_writereg(state, TS_FORMAT, 0);

	if (state->config->pll_init) {
		nxt6000_writereg(state, ENABLE_TUNER_IIC, 0x01);	/* open i2c bus switch */
		state->config->pll_init(fe);
		nxt6000_writereg(state, ENABLE_TUNER_IIC, 0x00);	/* close i2c bus switch */
	}
}

static void nxt6000_dump_status(struct nxt6000_state *state)
{
	u8 val;

/*
	printk("RS_COR_STAT: 0x%02X\n", nxt6000_readreg(fe, RS_COR_STAT));
	printk("VIT_SYNC_STATUS: 0x%02X\n", nxt6000_readreg(fe, VIT_SYNC_STATUS));
	printk("OFDM_COR_STAT: 0x%02X\n", nxt6000_readreg(fe, OFDM_COR_STAT));
	printk("OFDM_SYR_STAT: 0x%02X\n", nxt6000_readreg(fe, OFDM_SYR_STAT));
	printk("OFDM_TPS_RCVD_1: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_1));
	printk("OFDM_TPS_RCVD_2: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_2));
	printk("OFDM_TPS_RCVD_3: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_3));
	printk("OFDM_TPS_RCVD_4: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RCVD_4));
	printk("OFDM_TPS_RESERVED_1: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RESERVED_1));
	printk("OFDM_TPS_RESERVED_2: 0x%02X\n", nxt6000_readreg(fe, OFDM_TPS_RESERVED_2));
*/
	printk("NXT6000 status:");

	val = nxt6000_readreg(state, RS_COR_STAT);

	printk(" DATA DESCR LOCK: %d,", val & 0x01);
	printk(" DATA SYNC LOCK: %d,", (val >> 1) & 0x01);

	val = nxt6000_readreg(state, VIT_SYNC_STATUS);

	printk(" VITERBI LOCK: %d,", (val >> 7) & 0x01);

	switch ((val >> 4) & 0x07) {

	case 0x00:
		printk(" VITERBI CODERATE: 1/2,");
		break;

	case 0x01:
		printk(" VITERBI CODERATE: 2/3,");
		break;

	case 0x02:
		printk(" VITERBI CODERATE: 3/4,");
		break;

	case 0x03:
		printk(" VITERBI CODERATE: 5/6,");
		break;

	case 0x04:
		printk(" VITERBI CODERATE: 7/8,");
		break;

	default:
		printk(" VITERBI CODERATE: Reserved,");

	}

	val = nxt6000_readreg(state, OFDM_COR_STAT);

	printk(" CHCTrack: %d,", (val >> 7) & 0x01);
	printk(" TPSLock: %d,", (val >> 6) & 0x01);
	printk(" SYRLock: %d,", (val >> 5) & 0x01);
	printk(" AGCLock: %d,", (val >> 4) & 0x01);

	switch (val & 0x0F) {

	case 0x00:
		printk(" CoreState: IDLE,");
		break;

	case 0x02:
		printk(" CoreState: WAIT_AGC,");
		break;

	case 0x03:
		printk(" CoreState: WAIT_SYR,");
		break;

	case 0x04:
		printk(" CoreState: WAIT_PPM,");
		break;

	case 0x01:
		printk(" CoreState: WAIT_TRL,");
		break;

	case 0x05:
		printk(" CoreState: WAIT_TPS,");
		break;

	case 0x06:
		printk(" CoreState: MONITOR_TPS,");
		break;

	default:
		printk(" CoreState: Reserved,");

	}

	val = nxt6000_readreg(state, OFDM_SYR_STAT);

	printk(" SYRLock: %d,", (val >> 4) & 0x01);
	printk(" SYRMode: %s,", (val >> 2) & 0x01 ? "8K" : "2K");

	switch ((val >> 4) & 0x03) {

	case 0x00:
		printk(" SYRGuard: 1/32,");
		break;

	case 0x01:
		printk(" SYRGuard: 1/16,");
		break;

	case 0x02:
		printk(" SYRGuard: 1/8,");
		break;

	case 0x03:
		printk(" SYRGuard: 1/4,");
		break;
	}

	val = nxt6000_readreg(state, OFDM_TPS_RCVD_3);

	switch ((val >> 4) & 0x07) {

	case 0x00:
		printk(" TPSLP: 1/2,");
		break;

	case 0x01:
		printk(" TPSLP: 2/3,");
		break;

	case 0x02:
		printk(" TPSLP: 3/4,");
		break;

	case 0x03:
		printk(" TPSLP: 5/6,");
		break;

	case 0x04:
		printk(" TPSLP: 7/8,");
		break;

	default:
		printk(" TPSLP: Reserved,");

	}

	switch (val & 0x07) {

	case 0x00:
		printk(" TPSHP: 1/2,");
		break;

	case 0x01:
		printk(" TPSHP: 2/3,");
		break;

	case 0x02:
		printk(" TPSHP: 3/4,");
		break;

	case 0x03:
		printk(" TPSHP: 5/6,");
		break;

	case 0x04:
		printk(" TPSHP: 7/8,");
		break;

	default:
		printk(" TPSHP: Reserved,");

	}

	val = nxt6000_readreg(state, OFDM_TPS_RCVD_4);

	printk(" TPSMode: %s,", val & 0x01 ? "8K" : "2K");

	switch ((val >> 4) & 0x03) {

	case 0x00:
		printk(" TPSGuard: 1/32,");
		break;

	case 0x01:
		printk(" TPSGuard: 1/16,");
		break;

	case 0x02:
		printk(" TPSGuard: 1/8,");
		break;

	case 0x03:
		printk(" TPSGuard: 1/4,");
		break;

	}

	/* Strange magic required to gain access to RF_AGC_STATUS */
	nxt6000_readreg(state, RF_AGC_VAL_1);
	val = nxt6000_readreg(state, RF_AGC_STATUS);
	val = nxt6000_readreg(state, RF_AGC_STATUS);

	printk(" RF AGC LOCK: %d,", (val >> 4) & 0x01);
	printk("\n");
}

static int nxt6000_read_status(struct dvb_frontend* fe, fe_status_t* status)
{
	u8 core_status;
	struct nxt6000_state* state = fe->demodulator_priv;

	*status = 0;

	core_status = nxt6000_readreg(state, OFDM_COR_STAT);

	if (core_status & AGCLOCKED)
		*status |= FE_HAS_SIGNAL;

	if (nxt6000_readreg(state, OFDM_SYR_STAT) & GI14_SYR_LOCK)
		*status |= FE_HAS_CARRIER;

	if (nxt6000_readreg(state, VIT_SYNC_STATUS) & VITINSYNC)
		*status |= FE_HAS_VITERBI;

	if (nxt6000_readreg(state, RS_COR_STAT) & RSCORESTATUS)
		*status |= FE_HAS_SYNC;

	if ((core_status & TPSLOCKED) && (*status == (FE_HAS_SIGNAL | FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC)))
		*status |= FE_HAS_LOCK;

	if (debug)
		nxt6000_dump_status(state);

	return 0;
}

static int nxt6000_init(struct dvb_frontend* fe)
{
	struct nxt6000_state* state = fe->demodulator_priv;

	nxt6000_reset(state);
	nxt6000_setup(fe);

	return 0;
}

static int nxt6000_set_frontend(struct dvb_frontend* fe, struct dvb_frontend_parameters *param)
{
	struct nxt6000_state* state = fe->demodulator_priv;
	int result;

	nxt6000_writereg(state, ENABLE_TUNER_IIC, 0x01);	/* open i2c bus switch */
	state->config->pll_set(fe, param);
	nxt6000_writereg(state, ENABLE_TUNER_IIC, 0x00);	/* close i2c bus switch */

	if ((result = nxt6000_set_bandwidth(state, param->u.ofdm.bandwidth)) < 0)
		return result;
	if ((result = nxt6000_set_guard_interval(state, param->u.ofdm.guard_interval)) < 0)
		return result;
	if ((result = nxt6000_set_transmission_mode(state, param->u.ofdm.transmission_mode)) < 0)
		return result;
	if ((result = nxt6000_set_inversion(state, param->inversion)) < 0)
		return result;

	return 0;
}

static void nxt6000_release(struct dvb_frontend* fe)
{
	struct nxt6000_state* state = fe->demodulator_priv;
	kfree(state);
}

static int nxt6000_read_snr(struct dvb_frontend* fe, u16* snr)
{
	struct nxt6000_state* state = fe->demodulator_priv;

	*snr = nxt6000_readreg( state, OFDM_CHC_SNR) / 8;

	return 0;
}

static int nxt6000_read_ber(struct dvb_frontend* fe, u32* ber)
{
	struct nxt6000_state* state = fe->demodulator_priv;

	nxt6000_writereg( state, VIT_COR_INTSTAT, 0x18 );

	*ber = (nxt6000_readreg( state, VIT_BER_1 ) << 8 ) |
		nxt6000_readreg( state, VIT_BER_0 );

	nxt6000_writereg( state, VIT_COR_INTSTAT, 0x18); // Clear BER Done interrupts

	return 0;
}

static int nxt6000_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
{
	struct nxt6000_state* state = fe->demodulator_priv;

	*signal_strength = (short) (511 -
		(nxt6000_readreg(state, AGC_GAIN_1) +
		((nxt6000_readreg(state, AGC_GAIN_2) & 0x03) << 8)));

	return 0;
}

static struct dvb_frontend_ops nxt6000_ops;

struct dvb_frontend* nxt6000_attach(const struct nxt6000_config* config,
				    struct i2c_adapter* i2c)
{
	struct nxt6000_state* state = NULL;

	/* allocate memory for the internal state */
	state = kmalloc(sizeof(struct nxt6000_state), GFP_KERNEL);
	if (state == NULL) goto error;

	/* setup the state */
	state->config = config;
	state->i2c = i2c;
	memcpy(&state->ops, &nxt6000_ops, sizeof(struct dvb_frontend_ops));

	/* check if the demod is there */
	if (nxt6000_readreg(state, OFDM_MSC_REV) != NXT6000ASICDEVICE) goto error;

	/* create dvb_frontend */
	state->frontend.ops = &state->ops;
	state->frontend.demodulator_priv = state;
	return &state->frontend;

error:
	kfree(state);
	return NULL;
}

static struct dvb_frontend_ops nxt6000_ops = {

	.info = {
		.name = "NxtWave NXT6000 DVB-T",
		.type = FE_OFDM,
		.frequency_min = 0,
		.frequency_max = 863250000,
		.frequency_stepsize = 62500,
		/*.frequency_tolerance = *//* FIXME: 12% of SR */
		.symbol_rate_min = 0,	/* FIXME */
		.symbol_rate_max = 9360000,	/* FIXME */
		.symbol_rate_tolerance = 4000,
		.caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
	                FE_CAN_FEC_4_5 | FE_CAN_FEC_5_6 | FE_CAN_FEC_6_7 |
	                FE_CAN_FEC_7_8 | FE_CAN_FEC_8_9 | FE_CAN_FEC_AUTO |
	                FE_CAN_QAM_16 | FE_CAN_QAM_64 | FE_CAN_QAM_AUTO |
	                FE_CAN_TRANSMISSION_MODE_AUTO | FE_CAN_GUARD_INTERVAL_AUTO |
	                FE_CAN_HIERARCHY_AUTO,
	},

	.release = nxt6000_release,

	.init = nxt6000_init,

	.set_frontend = nxt6000_set_frontend,

	.read_status = nxt6000_read_status,
	.read_ber = nxt6000_read_ber,
	.read_signal_strength = nxt6000_read_signal_strength,
	.read_snr = nxt6000_read_snr,
};

module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");

MODULE_DESCRIPTION("NxtWave NXT6000 DVB-T demodulator driver");
MODULE_AUTHOR("Florian Schirmer");
MODULE_LICENSE("GPL");

EXPORT_SYMBOL(nxt6000_attach);