1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Driver for Zarlink DVB-T MT352 demodulator
4 *
5 *  Written by Holger Waechtler <holger@qanu.de>
6 *	 and Daniel Mack <daniel@qanu.de>
7 *
8 *  AVerMedia AVerTV DVB-T 771 support by
9 *       Wolfram Joost <dbox2@frokaschwei.de>
10 *
11 *  Support for Samsung TDTC9251DH01C(M) tuner
12 *  Copyright (C) 2004 Antonio Mancuso <antonio.mancuso@digitaltelevision.it>
13 *                     Amauri  Celani  <acelani@essegi.net>
14 *
15 *  DVICO FusionHDTV DVB-T1 and DVICO FusionHDTV DVB-T Lite support by
16 *       Christopher Pascoe <c.pascoe@itee.uq.edu.au>
17 */
18
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/init.h>
22#include <linux/delay.h>
23#include <linux/string.h>
24#include <linux/slab.h>
25
26#include <media/dvb_frontend.h>
27#include "mt352_priv.h"
28#include "mt352.h"
29
30struct mt352_state {
31	struct i2c_adapter* i2c;
32	struct dvb_frontend frontend;
33
34	/* configuration settings */
35	struct mt352_config config;
36};
37
38static int debug;
39#define dprintk(args...) \
40	do { \
41		if (debug) printk(KERN_DEBUG "mt352: " args); \
42	} while (0)
43
44static int mt352_single_write(struct dvb_frontend *fe, u8 reg, u8 val)
45{
46	struct mt352_state* state = fe->demodulator_priv;
47	u8 buf[2] = { reg, val };
48	struct i2c_msg msg = { .addr = state->config.demod_address, .flags = 0,
49			       .buf = buf, .len = 2 };
50	int err = i2c_transfer(state->i2c, &msg, 1);
51	if (err != 1) {
52		printk("mt352_write() to reg %x failed (err = %d)!\n", reg, err);
53		return err;
54	}
55	return 0;
56}
57
58static int _mt352_write(struct dvb_frontend* fe, const u8 ibuf[], int ilen)
59{
60	int err,i;
61	for (i=0; i < ilen-1; i++)
62		if ((err = mt352_single_write(fe,ibuf[0]+i,ibuf[i+1])))
63			return err;
64
65	return 0;
66}
67
68static int mt352_read_register(struct mt352_state* state, u8 reg)
69{
70	int ret;
71	u8 b0 [] = { reg };
72	u8 b1 [] = { 0 };
73	struct i2c_msg msg [] = { { .addr = state->config.demod_address,
74				    .flags = 0,
75				    .buf = b0, .len = 1 },
76				  { .addr = state->config.demod_address,
77				    .flags = I2C_M_RD,
78				    .buf = b1, .len = 1 } };
79
80	ret = i2c_transfer(state->i2c, msg, 2);
81
82	if (ret != 2) {
83		printk("%s: readreg error (reg=%d, ret==%i)\n",
84		       __func__, reg, ret);
85		return ret;
86	}
87
88	return b1[0];
89}
90
91static int mt352_sleep(struct dvb_frontend* fe)
92{
93	static u8 mt352_softdown[] = { CLOCK_CTL, 0x20, 0x08 };
94
95	_mt352_write(fe, mt352_softdown, sizeof(mt352_softdown));
96	return 0;
97}
98
99static void mt352_calc_nominal_rate(struct mt352_state* state,
100				    u32 bandwidth,
101				    unsigned char *buf)
102{
103	u32 adc_clock = 20480; /* 20.340 MHz */
104	u32 bw,value;
105
106	switch (bandwidth) {
107	case 6000000:
108		bw = 6;
109		break;
110	case 7000000:
111		bw = 7;
112		break;
113	case 8000000:
114	default:
115		bw = 8;
116		break;
117	}
118	if (state->config.adc_clock)
119		adc_clock = state->config.adc_clock;
120
121	value = 64 * bw * (1<<16) / (7 * 8);
122	value = value * 1000 / adc_clock;
123	dprintk("%s: bw %d, adc_clock %d => 0x%x\n",
124		__func__, bw, adc_clock, value);
125	buf[0] = msb(value);
126	buf[1] = lsb(value);
127}
128
129static void mt352_calc_input_freq(struct mt352_state* state,
130				  unsigned char *buf)
131{
132	int adc_clock = 20480; /* 20.480000 MHz */
133	int if2       = 36167; /* 36.166667 MHz */
134	int ife,value;
135
136	if (state->config.adc_clock)
137		adc_clock = state->config.adc_clock;
138	if (state->config.if2)
139		if2 = state->config.if2;
140
141	if (adc_clock >= if2 * 2)
142		ife = if2;
143	else {
144		ife = adc_clock - (if2 % adc_clock);
145		if (ife > adc_clock / 2)
146			ife = adc_clock - ife;
147	}
148	value = -16374 * ife / adc_clock;
149	dprintk("%s: if2 %d, ife %d, adc_clock %d => %d / 0x%x\n",
150		__func__, if2, ife, adc_clock, value, value & 0x3fff);
151	buf[0] = msb(value);
152	buf[1] = lsb(value);
153}
154
155static int mt352_set_parameters(struct dvb_frontend *fe)
156{
157	struct dtv_frontend_properties *op = &fe->dtv_property_cache;
158	struct mt352_state* state = fe->demodulator_priv;
159	unsigned char buf[13];
160	static unsigned char tuner_go[] = { 0x5d, 0x01 };
161	static unsigned char fsm_go[]   = { 0x5e, 0x01 };
162	unsigned int tps = 0;
163
164	switch (op->code_rate_HP) {
165		case FEC_2_3:
166			tps |= (1 << 7);
167			break;
168		case FEC_3_4:
169			tps |= (2 << 7);
170			break;
171		case FEC_5_6:
172			tps |= (3 << 7);
173			break;
174		case FEC_7_8:
175			tps |= (4 << 7);
176			break;
177		case FEC_1_2:
178		case FEC_AUTO:
179			break;
180		default:
181			return -EINVAL;
182	}
183
184	switch (op->code_rate_LP) {
185		case FEC_2_3:
186			tps |= (1 << 4);
187			break;
188		case FEC_3_4:
189			tps |= (2 << 4);
190			break;
191		case FEC_5_6:
192			tps |= (3 << 4);
193			break;
194		case FEC_7_8:
195			tps |= (4 << 4);
196			break;
197		case FEC_1_2:
198		case FEC_AUTO:
199			break;
200		case FEC_NONE:
201			if (op->hierarchy == HIERARCHY_AUTO ||
202			    op->hierarchy == HIERARCHY_NONE)
203				break;
204			fallthrough;
205		default:
206			return -EINVAL;
207	}
208
209	switch (op->modulation) {
210		case QPSK:
211			break;
212		case QAM_AUTO:
213		case QAM_16:
214			tps |= (1 << 13);
215			break;
216		case QAM_64:
217			tps |= (2 << 13);
218			break;
219		default:
220			return -EINVAL;
221	}
222
223	switch (op->transmission_mode) {
224		case TRANSMISSION_MODE_2K:
225		case TRANSMISSION_MODE_AUTO:
226			break;
227		case TRANSMISSION_MODE_8K:
228			tps |= (1 << 0);
229			break;
230		default:
231			return -EINVAL;
232	}
233
234	switch (op->guard_interval) {
235		case GUARD_INTERVAL_1_32:
236		case GUARD_INTERVAL_AUTO:
237			break;
238		case GUARD_INTERVAL_1_16:
239			tps |= (1 << 2);
240			break;
241		case GUARD_INTERVAL_1_8:
242			tps |= (2 << 2);
243			break;
244		case GUARD_INTERVAL_1_4:
245			tps |= (3 << 2);
246			break;
247		default:
248			return -EINVAL;
249	}
250
251	switch (op->hierarchy) {
252		case HIERARCHY_AUTO:
253		case HIERARCHY_NONE:
254			break;
255		case HIERARCHY_1:
256			tps |= (1 << 10);
257			break;
258		case HIERARCHY_2:
259			tps |= (2 << 10);
260			break;
261		case HIERARCHY_4:
262			tps |= (3 << 10);
263			break;
264		default:
265			return -EINVAL;
266	}
267
268
269	buf[0] = TPS_GIVEN_1; /* TPS_GIVEN_1 and following registers */
270
271	buf[1] = msb(tps);      /* TPS_GIVEN_(1|0) */
272	buf[2] = lsb(tps);
273
274	buf[3] = 0x50;  // old
275//	buf[3] = 0xf4;  // pinnacle
276
277	mt352_calc_nominal_rate(state, op->bandwidth_hz, buf+4);
278	mt352_calc_input_freq(state, buf+6);
279
280	if (state->config.no_tuner) {
281		if (fe->ops.tuner_ops.set_params) {
282			fe->ops.tuner_ops.set_params(fe);
283			if (fe->ops.i2c_gate_ctrl)
284				fe->ops.i2c_gate_ctrl(fe, 0);
285		}
286
287		_mt352_write(fe, buf, 8);
288		_mt352_write(fe, fsm_go, 2);
289	} else {
290		if (fe->ops.tuner_ops.calc_regs) {
291			fe->ops.tuner_ops.calc_regs(fe, buf+8, 5);
292			buf[8] <<= 1;
293			_mt352_write(fe, buf, sizeof(buf));
294			_mt352_write(fe, tuner_go, 2);
295		}
296	}
297
298	return 0;
299}
300
301static int mt352_get_parameters(struct dvb_frontend* fe,
302				struct dtv_frontend_properties *op)
303{
304	struct mt352_state* state = fe->demodulator_priv;
305	u16 tps;
306	u16 div;
307	u8 trl;
308	static const u8 tps_fec_to_api[8] =
309	{
310		FEC_1_2,
311		FEC_2_3,
312		FEC_3_4,
313		FEC_5_6,
314		FEC_7_8,
315		FEC_AUTO,
316		FEC_AUTO,
317		FEC_AUTO
318	};
319
320	if ( (mt352_read_register(state,0x00) & 0xC0) != 0xC0 )
321		return -EINVAL;
322
323	/* Use TPS_RECEIVED-registers, not the TPS_CURRENT-registers because
324	 * the mt352 sometimes works with the wrong parameters
325	 */
326	tps = (mt352_read_register(state, TPS_RECEIVED_1) << 8) | mt352_read_register(state, TPS_RECEIVED_0);
327	div = (mt352_read_register(state, CHAN_START_1) << 8) | mt352_read_register(state, CHAN_START_0);
328	trl = mt352_read_register(state, TRL_NOMINAL_RATE_1);
329
330	op->code_rate_HP = tps_fec_to_api[(tps >> 7) & 7];
331	op->code_rate_LP = tps_fec_to_api[(tps >> 4) & 7];
332
333	switch ( (tps >> 13) & 3)
334	{
335		case 0:
336			op->modulation = QPSK;
337			break;
338		case 1:
339			op->modulation = QAM_16;
340			break;
341		case 2:
342			op->modulation = QAM_64;
343			break;
344		default:
345			op->modulation = QAM_AUTO;
346			break;
347	}
348
349	op->transmission_mode = (tps & 0x01) ? TRANSMISSION_MODE_8K : TRANSMISSION_MODE_2K;
350
351	switch ( (tps >> 2) & 3)
352	{
353		case 0:
354			op->guard_interval = GUARD_INTERVAL_1_32;
355			break;
356		case 1:
357			op->guard_interval = GUARD_INTERVAL_1_16;
358			break;
359		case 2:
360			op->guard_interval = GUARD_INTERVAL_1_8;
361			break;
362		case 3:
363			op->guard_interval = GUARD_INTERVAL_1_4;
364			break;
365		default:
366			op->guard_interval = GUARD_INTERVAL_AUTO;
367			break;
368	}
369
370	switch ( (tps >> 10) & 7)
371	{
372		case 0:
373			op->hierarchy = HIERARCHY_NONE;
374			break;
375		case 1:
376			op->hierarchy = HIERARCHY_1;
377			break;
378		case 2:
379			op->hierarchy = HIERARCHY_2;
380			break;
381		case 3:
382			op->hierarchy = HIERARCHY_4;
383			break;
384		default:
385			op->hierarchy = HIERARCHY_AUTO;
386			break;
387	}
388
389	op->frequency = (500 * (div - IF_FREQUENCYx6)) / 3 * 1000;
390
391	if (trl == 0x72)
392		op->bandwidth_hz = 8000000;
393	else if (trl == 0x64)
394		op->bandwidth_hz = 7000000;
395	else
396		op->bandwidth_hz = 6000000;
397
398
399	if (mt352_read_register(state, STATUS_2) & 0x02)
400		op->inversion = INVERSION_OFF;
401	else
402		op->inversion = INVERSION_ON;
403
404	return 0;
405}
406
407static int mt352_read_status(struct dvb_frontend *fe, enum fe_status *status)
408{
409	struct mt352_state* state = fe->demodulator_priv;
410	int s0, s1, s3;
411
412	/* FIXME:
413	 *
414	 * The MT352 design manual from Zarlink states (page 46-47):
415	 *
416	 * Notes about the TUNER_GO register:
417	 *
418	 * If the Read_Tuner_Byte (bit-1) is activated, then the tuner status
419	 * byte is copied from the tuner to the STATUS_3 register and
420	 * completion of the read operation is indicated by bit-5 of the
421	 * INTERRUPT_3 register.
422	 */
423
424	if ((s0 = mt352_read_register(state, STATUS_0)) < 0)
425		return -EREMOTEIO;
426	if ((s1 = mt352_read_register(state, STATUS_1)) < 0)
427		return -EREMOTEIO;
428	if ((s3 = mt352_read_register(state, STATUS_3)) < 0)
429		return -EREMOTEIO;
430
431	*status = 0;
432	if (s0 & (1 << 4))
433		*status |= FE_HAS_CARRIER;
434	if (s0 & (1 << 1))
435		*status |= FE_HAS_VITERBI;
436	if (s0 & (1 << 5))
437		*status |= FE_HAS_LOCK;
438	if (s1 & (1 << 1))
439		*status |= FE_HAS_SYNC;
440	if (s3 & (1 << 6))
441		*status |= FE_HAS_SIGNAL;
442
443	if ((*status & (FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC)) !=
444		      (FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC))
445		*status &= ~FE_HAS_LOCK;
446
447	return 0;
448}
449
450static int mt352_read_ber(struct dvb_frontend* fe, u32* ber)
451{
452	struct mt352_state* state = fe->demodulator_priv;
453
454	*ber = (mt352_read_register (state, RS_ERR_CNT_2) << 16) |
455	       (mt352_read_register (state, RS_ERR_CNT_1) << 8) |
456	       (mt352_read_register (state, RS_ERR_CNT_0));
457
458	return 0;
459}
460
461static int mt352_read_signal_strength(struct dvb_frontend* fe, u16* strength)
462{
463	struct mt352_state* state = fe->demodulator_priv;
464
465	/* align the 12 bit AGC gain with the most significant bits */
466	u16 signal = ((mt352_read_register(state, AGC_GAIN_1) & 0x0f) << 12) |
467		(mt352_read_register(state, AGC_GAIN_0) << 4);
468
469	/* inverse of gain is signal strength */
470	*strength = ~signal;
471	return 0;
472}
473
474static int mt352_read_snr(struct dvb_frontend* fe, u16* snr)
475{
476	struct mt352_state* state = fe->demodulator_priv;
477
478	u8 _snr = mt352_read_register (state, SNR);
479	*snr = (_snr << 8) | _snr;
480
481	return 0;
482}
483
484static int mt352_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
485{
486	struct mt352_state* state = fe->demodulator_priv;
487
488	*ucblocks = (mt352_read_register (state,  RS_UBC_1) << 8) |
489		    (mt352_read_register (state,  RS_UBC_0));
490
491	return 0;
492}
493
494static int mt352_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fe_tune_settings)
495{
496	fe_tune_settings->min_delay_ms = 800;
497	fe_tune_settings->step_size = 0;
498	fe_tune_settings->max_drift = 0;
499
500	return 0;
501}
502
503static int mt352_init(struct dvb_frontend* fe)
504{
505	struct mt352_state* state = fe->demodulator_priv;
506
507	static u8 mt352_reset_attach [] = { RESET, 0xC0 };
508
509	dprintk("%s: hello\n",__func__);
510
511	if ((mt352_read_register(state, CLOCK_CTL) & 0x10) == 0 ||
512	    (mt352_read_register(state, CONFIG) & 0x20) == 0) {
513
514		/* Do a "hard" reset */
515		_mt352_write(fe, mt352_reset_attach, sizeof(mt352_reset_attach));
516		return state->config.demod_init(fe);
517	}
518
519	return 0;
520}
521
522static void mt352_release(struct dvb_frontend* fe)
523{
524	struct mt352_state* state = fe->demodulator_priv;
525	kfree(state);
526}
527
528static const struct dvb_frontend_ops mt352_ops;
529
530struct dvb_frontend* mt352_attach(const struct mt352_config* config,
531				  struct i2c_adapter* i2c)
532{
533	struct mt352_state* state = NULL;
534
535	/* allocate memory for the internal state */
536	state = kzalloc(sizeof(struct mt352_state), GFP_KERNEL);
537	if (state == NULL) goto error;
538
539	/* setup the state */
540	state->i2c = i2c;
541	memcpy(&state->config,config,sizeof(struct mt352_config));
542
543	/* check if the demod is there */
544	if (mt352_read_register(state, CHIP_ID) != ID_MT352) goto error;
545
546	/* create dvb_frontend */
547	memcpy(&state->frontend.ops, &mt352_ops, sizeof(struct dvb_frontend_ops));
548	state->frontend.demodulator_priv = state;
549	return &state->frontend;
550
551error:
552	kfree(state);
553	return NULL;
554}
555
556static const struct dvb_frontend_ops mt352_ops = {
557	.delsys = { SYS_DVBT },
558	.info = {
559		.name			= "Zarlink MT352 DVB-T",
560		.frequency_min_hz	= 174 * MHz,
561		.frequency_max_hz	= 862 * MHz,
562		.frequency_stepsize_hz	= 166667,
563		.caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 |
564			FE_CAN_FEC_3_4 | FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 |
565			FE_CAN_FEC_AUTO |
566			FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 | FE_CAN_QAM_AUTO |
567			FE_CAN_TRANSMISSION_MODE_AUTO | FE_CAN_GUARD_INTERVAL_AUTO |
568			FE_CAN_HIERARCHY_AUTO | FE_CAN_RECOVER |
569			FE_CAN_MUTE_TS
570	},
571
572	.release = mt352_release,
573
574	.init = mt352_init,
575	.sleep = mt352_sleep,
576	.write = _mt352_write,
577
578	.set_frontend = mt352_set_parameters,
579	.get_frontend = mt352_get_parameters,
580	.get_tune_settings = mt352_get_tune_settings,
581
582	.read_status = mt352_read_status,
583	.read_ber = mt352_read_ber,
584	.read_signal_strength = mt352_read_signal_strength,
585	.read_snr = mt352_read_snr,
586	.read_ucblocks = mt352_read_ucblocks,
587};
588
589module_param(debug, int, 0644);
590MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
591
592MODULE_DESCRIPTION("Zarlink MT352 DVB-T Demodulator driver");
593MODULE_AUTHOR("Holger Waechtler, Daniel Mack, Antonio Mancuso");
594MODULE_LICENSE("GPL");
595
596EXPORT_SYMBOL_GPL(mt352_attach);
597