1 /*
2  *  Driver for Zarlink DVB-T MT352 demodulator
3  *
4  *  Written by Holger Waechtler <holger@qanu.de>
5  *	 and Daniel Mack <daniel@qanu.de>
6  *
7  *  AVerMedia AVerTV DVB-T 771 support by
8  *       Wolfram Joost <dbox2@frokaschwei.de>
9  *
10  *  Support for Samsung TDTC9251DH01C(M) tuner
11  *  Copyright (C) 2004 Antonio Mancuso <antonio.mancuso@digitaltelevision.it>
12  *                     Amauri  Celani  <acelani@essegi.net>
13  *
14  *  DVICO FusionHDTV DVB-T1 and DVICO FusionHDTV DVB-T Lite support by
15  *       Christopher Pascoe <c.pascoe@itee.uq.edu.au>
16  *
17  *  This program is free software; you can redistribute it and/or modify
18  *  it under the terms of the GNU General Public License as published by
19  *  the Free Software Foundation; either version 2 of the License, or
20  *  (at your option) any later version.
21  *
22  *  This program is distributed in the hope that it will be useful,
23  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
24  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
25  *
26  *  GNU General Public License for more details.
27  *
28  *  You should have received a copy of the GNU General Public License
29  *  along with this program; if not, write to the Free Software
30  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.=
31  */
32 
33 #include <linux/kernel.h>
34 #include <linux/module.h>
35 #include <linux/init.h>
36 #include <linux/delay.h>
37 #include <linux/string.h>
38 #include <linux/slab.h>
39 
40 #include "dvb_frontend.h"
41 #include "mt352_priv.h"
42 #include "mt352.h"
43 
44 struct mt352_state {
45 	struct i2c_adapter* i2c;
46 	struct dvb_frontend frontend;
47 
48 	/* configuration settings */
49 	struct mt352_config config;
50 };
51 
52 static int debug;
53 #define dprintk(args...) \
54 	do { \
55 		if (debug) printk(KERN_DEBUG "mt352: " args); \
56 	} while (0)
57 
58 static int mt352_single_write(struct dvb_frontend *fe, u8 reg, u8 val)
59 {
60 	struct mt352_state* state = fe->demodulator_priv;
61 	u8 buf[2] = { reg, val };
62 	struct i2c_msg msg = { .addr = state->config.demod_address, .flags = 0,
63 			       .buf = buf, .len = 2 };
64 	int err = i2c_transfer(state->i2c, &msg, 1);
65 	if (err != 1) {
66 		printk("mt352_write() to reg %x failed (err = %d)!\n", reg, err);
67 		return err;
68 	}
69 	return 0;
70 }
71 
72 static int _mt352_write(struct dvb_frontend* fe, const u8 ibuf[], int ilen)
73 {
74 	int err,i;
75 	for (i=0; i < ilen-1; i++)
76 		if ((err = mt352_single_write(fe,ibuf[0]+i,ibuf[i+1])))
77 			return err;
78 
79 	return 0;
80 }
81 
82 static int mt352_read_register(struct mt352_state* state, u8 reg)
83 {
84 	int ret;
85 	u8 b0 [] = { reg };
86 	u8 b1 [] = { 0 };
87 	struct i2c_msg msg [] = { { .addr = state->config.demod_address,
88 				    .flags = 0,
89 				    .buf = b0, .len = 1 },
90 				  { .addr = state->config.demod_address,
91 				    .flags = I2C_M_RD,
92 				    .buf = b1, .len = 1 } };
93 
94 	ret = i2c_transfer(state->i2c, msg, 2);
95 
96 	if (ret != 2) {
97 		printk("%s: readreg error (reg=%d, ret==%i)\n",
98 		       __func__, reg, ret);
99 		return ret;
100 	}
101 
102 	return b1[0];
103 }
104 
105 static int mt352_sleep(struct dvb_frontend* fe)
106 {
107 	static u8 mt352_softdown[] = { CLOCK_CTL, 0x20, 0x08 };
108 
109 	_mt352_write(fe, mt352_softdown, sizeof(mt352_softdown));
110 	return 0;
111 }
112 
113 static void mt352_calc_nominal_rate(struct mt352_state* state,
114 				    u32 bandwidth,
115 				    unsigned char *buf)
116 {
117 	u32 adc_clock = 20480; /* 20.340 MHz */
118 	u32 bw,value;
119 
120 	switch (bandwidth) {
121 	case 6000000:
122 		bw = 6;
123 		break;
124 	case 7000000:
125 		bw = 7;
126 		break;
127 	case 8000000:
128 	default:
129 		bw = 8;
130 		break;
131 	}
132 	if (state->config.adc_clock)
133 		adc_clock = state->config.adc_clock;
134 
135 	value = 64 * bw * (1<<16) / (7 * 8);
136 	value = value * 1000 / adc_clock;
137 	dprintk("%s: bw %d, adc_clock %d => 0x%x\n",
138 		__func__, bw, adc_clock, value);
139 	buf[0] = msb(value);
140 	buf[1] = lsb(value);
141 }
142 
143 static void mt352_calc_input_freq(struct mt352_state* state,
144 				  unsigned char *buf)
145 {
146 	int adc_clock = 20480; /* 20.480000 MHz */
147 	int if2       = 36167; /* 36.166667 MHz */
148 	int ife,value;
149 
150 	if (state->config.adc_clock)
151 		adc_clock = state->config.adc_clock;
152 	if (state->config.if2)
153 		if2 = state->config.if2;
154 
155 	if (adc_clock >= if2 * 2)
156 		ife = if2;
157 	else {
158 		ife = adc_clock - (if2 % adc_clock);
159 		if (ife > adc_clock / 2)
160 			ife = adc_clock - ife;
161 	}
162 	value = -16374 * ife / adc_clock;
163 	dprintk("%s: if2 %d, ife %d, adc_clock %d => %d / 0x%x\n",
164 		__func__, if2, ife, adc_clock, value, value & 0x3fff);
165 	buf[0] = msb(value);
166 	buf[1] = lsb(value);
167 }
168 
169 static int mt352_set_parameters(struct dvb_frontend *fe)
170 {
171 	struct dtv_frontend_properties *op = &fe->dtv_property_cache;
172 	struct mt352_state* state = fe->demodulator_priv;
173 	unsigned char buf[13];
174 	static unsigned char tuner_go[] = { 0x5d, 0x01 };
175 	static unsigned char fsm_go[]   = { 0x5e, 0x01 };
176 	unsigned int tps = 0;
177 
178 	switch (op->code_rate_HP) {
179 		case FEC_2_3:
180 			tps |= (1 << 7);
181 			break;
182 		case FEC_3_4:
183 			tps |= (2 << 7);
184 			break;
185 		case FEC_5_6:
186 			tps |= (3 << 7);
187 			break;
188 		case FEC_7_8:
189 			tps |= (4 << 7);
190 			break;
191 		case FEC_1_2:
192 		case FEC_AUTO:
193 			break;
194 		default:
195 			return -EINVAL;
196 	}
197 
198 	switch (op->code_rate_LP) {
199 		case FEC_2_3:
200 			tps |= (1 << 4);
201 			break;
202 		case FEC_3_4:
203 			tps |= (2 << 4);
204 			break;
205 		case FEC_5_6:
206 			tps |= (3 << 4);
207 			break;
208 		case FEC_7_8:
209 			tps |= (4 << 4);
210 			break;
211 		case FEC_1_2:
212 		case FEC_AUTO:
213 			break;
214 		case FEC_NONE:
215 			if (op->hierarchy == HIERARCHY_AUTO ||
216 			    op->hierarchy == HIERARCHY_NONE)
217 				break;
218 		default:
219 			return -EINVAL;
220 	}
221 
222 	switch (op->modulation) {
223 		case QPSK:
224 			break;
225 		case QAM_AUTO:
226 		case QAM_16:
227 			tps |= (1 << 13);
228 			break;
229 		case QAM_64:
230 			tps |= (2 << 13);
231 			break;
232 		default:
233 			return -EINVAL;
234 	}
235 
236 	switch (op->transmission_mode) {
237 		case TRANSMISSION_MODE_2K:
238 		case TRANSMISSION_MODE_AUTO:
239 			break;
240 		case TRANSMISSION_MODE_8K:
241 			tps |= (1 << 0);
242 			break;
243 		default:
244 			return -EINVAL;
245 	}
246 
247 	switch (op->guard_interval) {
248 		case GUARD_INTERVAL_1_32:
249 		case GUARD_INTERVAL_AUTO:
250 			break;
251 		case GUARD_INTERVAL_1_16:
252 			tps |= (1 << 2);
253 			break;
254 		case GUARD_INTERVAL_1_8:
255 			tps |= (2 << 2);
256 			break;
257 		case GUARD_INTERVAL_1_4:
258 			tps |= (3 << 2);
259 			break;
260 		default:
261 			return -EINVAL;
262 	}
263 
264 	switch (op->hierarchy) {
265 		case HIERARCHY_AUTO:
266 		case HIERARCHY_NONE:
267 			break;
268 		case HIERARCHY_1:
269 			tps |= (1 << 10);
270 			break;
271 		case HIERARCHY_2:
272 			tps |= (2 << 10);
273 			break;
274 		case HIERARCHY_4:
275 			tps |= (3 << 10);
276 			break;
277 		default:
278 			return -EINVAL;
279 	}
280 
281 
282 	buf[0] = TPS_GIVEN_1; /* TPS_GIVEN_1 and following registers */
283 
284 	buf[1] = msb(tps);      /* TPS_GIVEN_(1|0) */
285 	buf[2] = lsb(tps);
286 
287 	buf[3] = 0x50;  // old
288 //	buf[3] = 0xf4;  // pinnacle
289 
290 	mt352_calc_nominal_rate(state, op->bandwidth_hz, buf+4);
291 	mt352_calc_input_freq(state, buf+6);
292 
293 	if (state->config.no_tuner) {
294 		if (fe->ops.tuner_ops.set_params) {
295 			fe->ops.tuner_ops.set_params(fe);
296 			if (fe->ops.i2c_gate_ctrl)
297 				fe->ops.i2c_gate_ctrl(fe, 0);
298 		}
299 
300 		_mt352_write(fe, buf, 8);
301 		_mt352_write(fe, fsm_go, 2);
302 	} else {
303 		if (fe->ops.tuner_ops.calc_regs) {
304 			fe->ops.tuner_ops.calc_regs(fe, buf+8, 5);
305 			buf[8] <<= 1;
306 			_mt352_write(fe, buf, sizeof(buf));
307 			_mt352_write(fe, tuner_go, 2);
308 		}
309 	}
310 
311 	return 0;
312 }
313 
314 static int mt352_get_parameters(struct dvb_frontend* fe,
315 				struct dtv_frontend_properties *op)
316 {
317 	struct mt352_state* state = fe->demodulator_priv;
318 	u16 tps;
319 	u16 div;
320 	u8 trl;
321 	static const u8 tps_fec_to_api[8] =
322 	{
323 		FEC_1_2,
324 		FEC_2_3,
325 		FEC_3_4,
326 		FEC_5_6,
327 		FEC_7_8,
328 		FEC_AUTO,
329 		FEC_AUTO,
330 		FEC_AUTO
331 	};
332 
333 	if ( (mt352_read_register(state,0x00) & 0xC0) != 0xC0 )
334 		return -EINVAL;
335 
336 	/* Use TPS_RECEIVED-registers, not the TPS_CURRENT-registers because
337 	 * the mt352 sometimes works with the wrong parameters
338 	 */
339 	tps = (mt352_read_register(state, TPS_RECEIVED_1) << 8) | mt352_read_register(state, TPS_RECEIVED_0);
340 	div = (mt352_read_register(state, CHAN_START_1) << 8) | mt352_read_register(state, CHAN_START_0);
341 	trl = mt352_read_register(state, TRL_NOMINAL_RATE_1);
342 
343 	op->code_rate_HP = tps_fec_to_api[(tps >> 7) & 7];
344 	op->code_rate_LP = tps_fec_to_api[(tps >> 4) & 7];
345 
346 	switch ( (tps >> 13) & 3)
347 	{
348 		case 0:
349 			op->modulation = QPSK;
350 			break;
351 		case 1:
352 			op->modulation = QAM_16;
353 			break;
354 		case 2:
355 			op->modulation = QAM_64;
356 			break;
357 		default:
358 			op->modulation = QAM_AUTO;
359 			break;
360 	}
361 
362 	op->transmission_mode = (tps & 0x01) ? TRANSMISSION_MODE_8K : TRANSMISSION_MODE_2K;
363 
364 	switch ( (tps >> 2) & 3)
365 	{
366 		case 0:
367 			op->guard_interval = GUARD_INTERVAL_1_32;
368 			break;
369 		case 1:
370 			op->guard_interval = GUARD_INTERVAL_1_16;
371 			break;
372 		case 2:
373 			op->guard_interval = GUARD_INTERVAL_1_8;
374 			break;
375 		case 3:
376 			op->guard_interval = GUARD_INTERVAL_1_4;
377 			break;
378 		default:
379 			op->guard_interval = GUARD_INTERVAL_AUTO;
380 			break;
381 	}
382 
383 	switch ( (tps >> 10) & 7)
384 	{
385 		case 0:
386 			op->hierarchy = HIERARCHY_NONE;
387 			break;
388 		case 1:
389 			op->hierarchy = HIERARCHY_1;
390 			break;
391 		case 2:
392 			op->hierarchy = HIERARCHY_2;
393 			break;
394 		case 3:
395 			op->hierarchy = HIERARCHY_4;
396 			break;
397 		default:
398 			op->hierarchy = HIERARCHY_AUTO;
399 			break;
400 	}
401 
402 	op->frequency = (500 * (div - IF_FREQUENCYx6)) / 3 * 1000;
403 
404 	if (trl == 0x72)
405 		op->bandwidth_hz = 8000000;
406 	else if (trl == 0x64)
407 		op->bandwidth_hz = 7000000;
408 	else
409 		op->bandwidth_hz = 6000000;
410 
411 
412 	if (mt352_read_register(state, STATUS_2) & 0x02)
413 		op->inversion = INVERSION_OFF;
414 	else
415 		op->inversion = INVERSION_ON;
416 
417 	return 0;
418 }
419 
420 static int mt352_read_status(struct dvb_frontend *fe, enum fe_status *status)
421 {
422 	struct mt352_state* state = fe->demodulator_priv;
423 	int s0, s1, s3;
424 
425 	/* FIXME:
426 	 *
427 	 * The MT352 design manual from Zarlink states (page 46-47):
428 	 *
429 	 * Notes about the TUNER_GO register:
430 	 *
431 	 * If the Read_Tuner_Byte (bit-1) is activated, then the tuner status
432 	 * byte is copied from the tuner to the STATUS_3 register and
433 	 * completion of the read operation is indicated by bit-5 of the
434 	 * INTERRUPT_3 register.
435 	 */
436 
437 	if ((s0 = mt352_read_register(state, STATUS_0)) < 0)
438 		return -EREMOTEIO;
439 	if ((s1 = mt352_read_register(state, STATUS_1)) < 0)
440 		return -EREMOTEIO;
441 	if ((s3 = mt352_read_register(state, STATUS_3)) < 0)
442 		return -EREMOTEIO;
443 
444 	*status = 0;
445 	if (s0 & (1 << 4))
446 		*status |= FE_HAS_CARRIER;
447 	if (s0 & (1 << 1))
448 		*status |= FE_HAS_VITERBI;
449 	if (s0 & (1 << 5))
450 		*status |= FE_HAS_LOCK;
451 	if (s1 & (1 << 1))
452 		*status |= FE_HAS_SYNC;
453 	if (s3 & (1 << 6))
454 		*status |= FE_HAS_SIGNAL;
455 
456 	if ((*status & (FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC)) !=
457 		      (FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC))
458 		*status &= ~FE_HAS_LOCK;
459 
460 	return 0;
461 }
462 
463 static int mt352_read_ber(struct dvb_frontend* fe, u32* ber)
464 {
465 	struct mt352_state* state = fe->demodulator_priv;
466 
467 	*ber = (mt352_read_register (state, RS_ERR_CNT_2) << 16) |
468 	       (mt352_read_register (state, RS_ERR_CNT_1) << 8) |
469 	       (mt352_read_register (state, RS_ERR_CNT_0));
470 
471 	return 0;
472 }
473 
474 static int mt352_read_signal_strength(struct dvb_frontend* fe, u16* strength)
475 {
476 	struct mt352_state* state = fe->demodulator_priv;
477 
478 	/* align the 12 bit AGC gain with the most significant bits */
479 	u16 signal = ((mt352_read_register(state, AGC_GAIN_1) & 0x0f) << 12) |
480 		(mt352_read_register(state, AGC_GAIN_0) << 4);
481 
482 	/* inverse of gain is signal strength */
483 	*strength = ~signal;
484 	return 0;
485 }
486 
487 static int mt352_read_snr(struct dvb_frontend* fe, u16* snr)
488 {
489 	struct mt352_state* state = fe->demodulator_priv;
490 
491 	u8 _snr = mt352_read_register (state, SNR);
492 	*snr = (_snr << 8) | _snr;
493 
494 	return 0;
495 }
496 
497 static int mt352_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
498 {
499 	struct mt352_state* state = fe->demodulator_priv;
500 
501 	*ucblocks = (mt352_read_register (state,  RS_UBC_1) << 8) |
502 		    (mt352_read_register (state,  RS_UBC_0));
503 
504 	return 0;
505 }
506 
507 static int mt352_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fe_tune_settings)
508 {
509 	fe_tune_settings->min_delay_ms = 800;
510 	fe_tune_settings->step_size = 0;
511 	fe_tune_settings->max_drift = 0;
512 
513 	return 0;
514 }
515 
516 static int mt352_init(struct dvb_frontend* fe)
517 {
518 	struct mt352_state* state = fe->demodulator_priv;
519 
520 	static u8 mt352_reset_attach [] = { RESET, 0xC0 };
521 
522 	dprintk("%s: hello\n",__func__);
523 
524 	if ((mt352_read_register(state, CLOCK_CTL) & 0x10) == 0 ||
525 	    (mt352_read_register(state, CONFIG) & 0x20) == 0) {
526 
527 		/* Do a "hard" reset */
528 		_mt352_write(fe, mt352_reset_attach, sizeof(mt352_reset_attach));
529 		return state->config.demod_init(fe);
530 	}
531 
532 	return 0;
533 }
534 
535 static void mt352_release(struct dvb_frontend* fe)
536 {
537 	struct mt352_state* state = fe->demodulator_priv;
538 	kfree(state);
539 }
540 
541 static struct dvb_frontend_ops mt352_ops;
542 
543 struct dvb_frontend* mt352_attach(const struct mt352_config* config,
544 				  struct i2c_adapter* i2c)
545 {
546 	struct mt352_state* state = NULL;
547 
548 	/* allocate memory for the internal state */
549 	state = kzalloc(sizeof(struct mt352_state), GFP_KERNEL);
550 	if (state == NULL) goto error;
551 
552 	/* setup the state */
553 	state->i2c = i2c;
554 	memcpy(&state->config,config,sizeof(struct mt352_config));
555 
556 	/* check if the demod is there */
557 	if (mt352_read_register(state, CHIP_ID) != ID_MT352) goto error;
558 
559 	/* create dvb_frontend */
560 	memcpy(&state->frontend.ops, &mt352_ops, sizeof(struct dvb_frontend_ops));
561 	state->frontend.demodulator_priv = state;
562 	return &state->frontend;
563 
564 error:
565 	kfree(state);
566 	return NULL;
567 }
568 
569 static struct dvb_frontend_ops mt352_ops = {
570 	.delsys = { SYS_DVBT },
571 	.info = {
572 		.name			= "Zarlink MT352 DVB-T",
573 		.frequency_min		= 174000000,
574 		.frequency_max		= 862000000,
575 		.frequency_stepsize	= 166667,
576 		.frequency_tolerance	= 0,
577 		.caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 |
578 			FE_CAN_FEC_3_4 | FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 |
579 			FE_CAN_FEC_AUTO |
580 			FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 | FE_CAN_QAM_AUTO |
581 			FE_CAN_TRANSMISSION_MODE_AUTO | FE_CAN_GUARD_INTERVAL_AUTO |
582 			FE_CAN_HIERARCHY_AUTO | FE_CAN_RECOVER |
583 			FE_CAN_MUTE_TS
584 	},
585 
586 	.release = mt352_release,
587 
588 	.init = mt352_init,
589 	.sleep = mt352_sleep,
590 	.write = _mt352_write,
591 
592 	.set_frontend = mt352_set_parameters,
593 	.get_frontend = mt352_get_parameters,
594 	.get_tune_settings = mt352_get_tune_settings,
595 
596 	.read_status = mt352_read_status,
597 	.read_ber = mt352_read_ber,
598 	.read_signal_strength = mt352_read_signal_strength,
599 	.read_snr = mt352_read_snr,
600 	.read_ucblocks = mt352_read_ucblocks,
601 };
602 
603 module_param(debug, int, 0644);
604 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
605 
606 MODULE_DESCRIPTION("Zarlink MT352 DVB-T Demodulator driver");
607 MODULE_AUTHOR("Holger Waechtler, Daniel Mack, Antonio Mancuso");
608 MODULE_LICENSE("GPL");
609 
610 EXPORT_SYMBOL(mt352_attach);
611