xref: /linux/drivers/media/tuners/mt2060.c (revision 906fd46a65383cd639e5eec72a047efc33045d86)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Driver for Microtune MT2060 "Single chip dual conversion broadband tuner"
4  *
5  *  Copyright (c) 2006 Olivier DANET <odanet@caramail.com>
6  */
7 
8 /* In that file, frequencies are expressed in kiloHertz to avoid 32 bits overflows */
9 
10 #include <linux/module.h>
11 #include <linux/delay.h>
12 #include <linux/dvb/frontend.h>
13 #include <linux/i2c.h>
14 #include <linux/slab.h>
15 
16 #include <media/dvb_frontend.h>
17 
18 #include "mt2060.h"
19 #include "mt2060_priv.h"
20 
21 static int debug;
22 module_param(debug, int, 0644);
23 MODULE_PARM_DESC(debug, "Turn on/off debugging (default:off).");
24 
25 #define dprintk(args...) do { if (debug) {printk(KERN_DEBUG "MT2060: " args); printk("\n"); }} while (0)
26 
27 // Reads a single register
28 static int mt2060_readreg(struct mt2060_priv *priv, u8 reg, u8 *val)
29 {
30 	struct i2c_msg msg[2] = {
31 		{ .addr = priv->cfg->i2c_address, .flags = 0, .len = 1 },
32 		{ .addr = priv->cfg->i2c_address, .flags = I2C_M_RD, .len = 1 },
33 	};
34 	int rc = 0;
35 	u8 *b;
36 
37 	b = kmalloc(2, GFP_KERNEL);
38 	if (!b)
39 		return -ENOMEM;
40 
41 	b[0] = reg;
42 	b[1] = 0;
43 
44 	msg[0].buf = b;
45 	msg[1].buf = b + 1;
46 
47 	if (i2c_transfer(priv->i2c, msg, 2) != 2) {
48 		printk(KERN_WARNING "mt2060 I2C read failed\n");
49 		rc = -EREMOTEIO;
50 	}
51 	*val = b[1];
52 	kfree(b);
53 
54 	return rc;
55 }
56 
57 // Writes a single register
58 static int mt2060_writereg(struct mt2060_priv *priv, u8 reg, u8 val)
59 {
60 	struct i2c_msg msg = {
61 		.addr = priv->cfg->i2c_address, .flags = 0, .len = 2
62 	};
63 	u8 *buf;
64 	int rc = 0;
65 
66 	buf = kmalloc(2, GFP_KERNEL);
67 	if (!buf)
68 		return -ENOMEM;
69 
70 	buf[0] = reg;
71 	buf[1] = val;
72 
73 	msg.buf = buf;
74 
75 	if (i2c_transfer(priv->i2c, &msg, 1) != 1) {
76 		printk(KERN_WARNING "mt2060 I2C write failed\n");
77 		rc = -EREMOTEIO;
78 	}
79 	kfree(buf);
80 	return rc;
81 }
82 
83 // Writes a set of consecutive registers
84 static int mt2060_writeregs(struct mt2060_priv *priv,u8 *buf, u8 len)
85 {
86 	int rem, val_len;
87 	u8 *xfer_buf;
88 	int rc = 0;
89 	struct i2c_msg msg = {
90 		.addr = priv->cfg->i2c_address, .flags = 0
91 	};
92 
93 	xfer_buf = kmalloc(16, GFP_KERNEL);
94 	if (!xfer_buf)
95 		return -ENOMEM;
96 
97 	msg.buf = xfer_buf;
98 
99 	for (rem = len - 1; rem > 0; rem -= priv->i2c_max_regs) {
100 		val_len = min_t(int, rem, priv->i2c_max_regs);
101 		msg.len = 1 + val_len;
102 		xfer_buf[0] = buf[0] + len - 1 - rem;
103 		memcpy(&xfer_buf[1], &buf[1 + len - 1 - rem], val_len);
104 
105 		if (i2c_transfer(priv->i2c, &msg, 1) != 1) {
106 			printk(KERN_WARNING "mt2060 I2C write failed (len=%i)\n", val_len);
107 			rc = -EREMOTEIO;
108 			break;
109 		}
110 	}
111 
112 	kfree(xfer_buf);
113 	return rc;
114 }
115 
116 // Initialisation sequences
117 // LNABAND=3, NUM1=0x3C, DIV1=0x74, NUM2=0x1080, DIV2=0x49
118 static u8 mt2060_config1[] = {
119 	REG_LO1C1,
120 	0x3F,	0x74,	0x00,	0x08,	0x93
121 };
122 
123 // FMCG=2, GP2=0, GP1=0
124 static u8 mt2060_config2[] = {
125 	REG_MISC_CTRL,
126 	0x20,	0x1E,	0x30,	0xff,	0x80,	0xff,	0x00,	0x2c,	0x42
127 };
128 
129 //  VGAG=3, V1CSE=1
130 
131 #ifdef  MT2060_SPURCHECK
132 /* The function below calculates the frequency offset between the output frequency if2
133  and the closer cross modulation subcarrier between lo1 and lo2 up to the tenth harmonic */
134 static int mt2060_spurcalc(u32 lo1,u32 lo2,u32 if2)
135 {
136 	int I,J;
137 	int dia,diamin,diff;
138 	diamin=1000000;
139 	for (I = 1; I < 10; I++) {
140 		J = ((2*I*lo1)/lo2+1)/2;
141 		diff = I*(int)lo1-J*(int)lo2;
142 		if (diff < 0) diff=-diff;
143 		dia = (diff-(int)if2);
144 		if (dia < 0) dia=-dia;
145 		if (diamin > dia) diamin=dia;
146 	}
147 	return diamin;
148 }
149 
150 #define BANDWIDTH 4000 // kHz
151 
152 /* Calculates the frequency offset to add to avoid spurs. Returns 0 if no offset is needed */
153 static int mt2060_spurcheck(u32 lo1,u32 lo2,u32 if2)
154 {
155 	u32 Spur,Sp1,Sp2;
156 	int I,J;
157 	I=0;
158 	J=1000;
159 
160 	Spur=mt2060_spurcalc(lo1,lo2,if2);
161 	if (Spur < BANDWIDTH) {
162 		/* Potential spurs detected */
163 		dprintk("Spurs before : f_lo1: %d  f_lo2: %d  (kHz)",
164 			(int)lo1,(int)lo2);
165 		I=1000;
166 		Sp1 = mt2060_spurcalc(lo1+I,lo2+I,if2);
167 		Sp2 = mt2060_spurcalc(lo1-I,lo2-I,if2);
168 
169 		if (Sp1 < Sp2) {
170 			J=-J; I=-I; Spur=Sp2;
171 		} else
172 			Spur=Sp1;
173 
174 		while (Spur < BANDWIDTH) {
175 			I += J;
176 			Spur = mt2060_spurcalc(lo1+I,lo2+I,if2);
177 		}
178 		dprintk("Spurs after  : f_lo1: %d  f_lo2: %d  (kHz)",
179 			(int)(lo1+I),(int)(lo2+I));
180 	}
181 	return I;
182 }
183 #endif
184 
185 #define IF2  36150       // IF2 frequency = 36.150 MHz
186 #define FREF 16000       // Quartz oscillator 16 MHz
187 
188 static int mt2060_set_params(struct dvb_frontend *fe)
189 {
190 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
191 	struct mt2060_priv *priv;
192 	int i=0;
193 	u32 freq;
194 	u8  lnaband;
195 	u32 f_lo1,f_lo2;
196 	u32 div1,num1,div2,num2;
197 	u8  b[8];
198 	u32 if1;
199 
200 	priv = fe->tuner_priv;
201 
202 	if1 = priv->if1_freq;
203 	b[0] = REG_LO1B1;
204 	b[1] = 0xFF;
205 
206 	if (fe->ops.i2c_gate_ctrl)
207 		fe->ops.i2c_gate_ctrl(fe, 1); /* open i2c_gate */
208 
209 	mt2060_writeregs(priv,b,2);
210 
211 	freq = c->frequency / 1000; /* Hz -> kHz */
212 
213 	f_lo1 = freq + if1 * 1000;
214 	f_lo1 = (f_lo1 / 250) * 250;
215 	f_lo2 = f_lo1 - freq - IF2;
216 	// From the Comtech datasheet, the step used is 50kHz. The tuner chip could be more precise
217 	f_lo2 = ((f_lo2 + 25) / 50) * 50;
218 	priv->frequency =  (f_lo1 - f_lo2 - IF2) * 1000;
219 
220 #ifdef MT2060_SPURCHECK
221 	// LO-related spurs detection and correction
222 	num1   = mt2060_spurcheck(f_lo1,f_lo2,IF2);
223 	f_lo1 += num1;
224 	f_lo2 += num1;
225 #endif
226 	//Frequency LO1 = 16MHz * (DIV1 + NUM1/64 )
227 	num1 = f_lo1 / (FREF / 64);
228 	div1 = num1 / 64;
229 	num1 &= 0x3f;
230 
231 	// Frequency LO2 = 16MHz * (DIV2 + NUM2/8192 )
232 	num2 = f_lo2 * 64 / (FREF / 128);
233 	div2 = num2 / 8192;
234 	num2 &= 0x1fff;
235 
236 	if (freq <=  95000) lnaband = 0xB0; else
237 	if (freq <= 180000) lnaband = 0xA0; else
238 	if (freq <= 260000) lnaband = 0x90; else
239 	if (freq <= 335000) lnaband = 0x80; else
240 	if (freq <= 425000) lnaband = 0x70; else
241 	if (freq <= 480000) lnaband = 0x60; else
242 	if (freq <= 570000) lnaband = 0x50; else
243 	if (freq <= 645000) lnaband = 0x40; else
244 	if (freq <= 730000) lnaband = 0x30; else
245 	if (freq <= 810000) lnaband = 0x20; else lnaband = 0x10;
246 
247 	b[0] = REG_LO1C1;
248 	b[1] = lnaband | ((num1 >>2) & 0x0F);
249 	b[2] = div1;
250 	b[3] = (num2 & 0x0F)  | ((num1 & 3) << 4);
251 	b[4] = num2 >> 4;
252 	b[5] = ((num2 >>12) & 1) | (div2 << 1);
253 
254 	dprintk("IF1: %dMHz",(int)if1);
255 	dprintk("PLL freq=%dkHz  f_lo1=%dkHz  f_lo2=%dkHz",(int)freq,(int)f_lo1,(int)f_lo2);
256 	dprintk("PLL div1=%d  num1=%d  div2=%d  num2=%d",(int)div1,(int)num1,(int)div2,(int)num2);
257 	dprintk("PLL [1..5]: %2x %2x %2x %2x %2x",(int)b[1],(int)b[2],(int)b[3],(int)b[4],(int)b[5]);
258 
259 	mt2060_writeregs(priv,b,6);
260 
261 	//Waits for pll lock or timeout
262 	i = 0;
263 	do {
264 		mt2060_readreg(priv,REG_LO_STATUS,b);
265 		if ((b[0] & 0x88)==0x88)
266 			break;
267 		msleep(4);
268 		i++;
269 	} while (i<10);
270 
271 	if (fe->ops.i2c_gate_ctrl)
272 		fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */
273 
274 	return 0;
275 }
276 
277 static void mt2060_calibrate(struct mt2060_priv *priv)
278 {
279 	u8 b = 0;
280 	int i = 0;
281 
282 	if (mt2060_writeregs(priv,mt2060_config1,sizeof(mt2060_config1)))
283 		return;
284 	if (mt2060_writeregs(priv,mt2060_config2,sizeof(mt2060_config2)))
285 		return;
286 
287 	/* initialize the clock output */
288 	mt2060_writereg(priv, REG_VGAG, (priv->cfg->clock_out << 6) | 0x30);
289 
290 	do {
291 		b |= (1 << 6); // FM1SS;
292 		mt2060_writereg(priv, REG_LO2C1,b);
293 		msleep(20);
294 
295 		if (i == 0) {
296 			b |= (1 << 7); // FM1CA;
297 			mt2060_writereg(priv, REG_LO2C1,b);
298 			b &= ~(1 << 7); // FM1CA;
299 			msleep(20);
300 		}
301 
302 		b &= ~(1 << 6); // FM1SS
303 		mt2060_writereg(priv, REG_LO2C1,b);
304 
305 		msleep(20);
306 		i++;
307 	} while (i < 9);
308 
309 	i = 0;
310 	while (i++ < 10 && mt2060_readreg(priv, REG_MISC_STAT, &b) == 0 && (b & (1 << 6)) == 0)
311 		msleep(20);
312 
313 	if (i <= 10) {
314 		mt2060_readreg(priv, REG_FM_FREQ, &priv->fmfreq); // now find out, what is fmreq used for :)
315 		dprintk("calibration was successful: %d", (int)priv->fmfreq);
316 	} else
317 		dprintk("FMCAL timed out");
318 }
319 
320 static int mt2060_get_frequency(struct dvb_frontend *fe, u32 *frequency)
321 {
322 	struct mt2060_priv *priv = fe->tuner_priv;
323 	*frequency = priv->frequency;
324 	return 0;
325 }
326 
327 static int mt2060_get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
328 {
329 	*frequency = IF2 * 1000;
330 	return 0;
331 }
332 
333 static int mt2060_init(struct dvb_frontend *fe)
334 {
335 	struct mt2060_priv *priv = fe->tuner_priv;
336 	int ret;
337 
338 	if (fe->ops.i2c_gate_ctrl)
339 		fe->ops.i2c_gate_ctrl(fe, 1); /* open i2c_gate */
340 
341 	if (priv->sleep) {
342 		ret = mt2060_writereg(priv, REG_MISC_CTRL, 0x20);
343 		if (ret)
344 			goto err_i2c_gate_ctrl;
345 	}
346 
347 	ret = mt2060_writereg(priv, REG_VGAG,
348 			      (priv->cfg->clock_out << 6) | 0x33);
349 
350 err_i2c_gate_ctrl:
351 	if (fe->ops.i2c_gate_ctrl)
352 		fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */
353 
354 	return ret;
355 }
356 
357 static int mt2060_sleep(struct dvb_frontend *fe)
358 {
359 	struct mt2060_priv *priv = fe->tuner_priv;
360 	int ret;
361 
362 	if (fe->ops.i2c_gate_ctrl)
363 		fe->ops.i2c_gate_ctrl(fe, 1); /* open i2c_gate */
364 
365 	ret = mt2060_writereg(priv, REG_VGAG,
366 			      (priv->cfg->clock_out << 6) | 0x30);
367 	if (ret)
368 		goto err_i2c_gate_ctrl;
369 
370 	if (priv->sleep)
371 		ret = mt2060_writereg(priv, REG_MISC_CTRL, 0xe8);
372 
373 err_i2c_gate_ctrl:
374 	if (fe->ops.i2c_gate_ctrl)
375 		fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */
376 
377 	return ret;
378 }
379 
380 static void mt2060_release(struct dvb_frontend *fe)
381 {
382 	kfree(fe->tuner_priv);
383 	fe->tuner_priv = NULL;
384 }
385 
386 static const struct dvb_tuner_ops mt2060_tuner_ops = {
387 	.info = {
388 		.name              = "Microtune MT2060",
389 		.frequency_min_hz  =  48 * MHz,
390 		.frequency_max_hz  = 860 * MHz,
391 		.frequency_step_hz =  50 * kHz,
392 	},
393 
394 	.release       = mt2060_release,
395 
396 	.init          = mt2060_init,
397 	.sleep         = mt2060_sleep,
398 
399 	.set_params    = mt2060_set_params,
400 	.get_frequency = mt2060_get_frequency,
401 	.get_if_frequency = mt2060_get_if_frequency,
402 };
403 
404 /* This functions tries to identify a MT2060 tuner by reading the PART/REV register. This is hasty. */
405 struct dvb_frontend * mt2060_attach(struct dvb_frontend *fe, struct i2c_adapter *i2c, struct mt2060_config *cfg, u16 if1)
406 {
407 	struct mt2060_priv *priv = NULL;
408 	u8 id = 0;
409 
410 	priv = kzalloc(sizeof(struct mt2060_priv), GFP_KERNEL);
411 	if (priv == NULL)
412 		return NULL;
413 
414 	priv->cfg      = cfg;
415 	priv->i2c      = i2c;
416 	priv->if1_freq = if1;
417 	priv->i2c_max_regs = ~0;
418 
419 	if (fe->ops.i2c_gate_ctrl)
420 		fe->ops.i2c_gate_ctrl(fe, 1); /* open i2c_gate */
421 
422 	if (mt2060_readreg(priv,REG_PART_REV,&id) != 0) {
423 		kfree(priv);
424 		return NULL;
425 	}
426 
427 	if (id != PART_REV) {
428 		kfree(priv);
429 		return NULL;
430 	}
431 	printk(KERN_INFO "MT2060: successfully identified (IF1 = %d)\n", if1);
432 	memcpy(&fe->ops.tuner_ops, &mt2060_tuner_ops, sizeof(struct dvb_tuner_ops));
433 
434 	fe->tuner_priv = priv;
435 
436 	mt2060_calibrate(priv);
437 
438 	if (fe->ops.i2c_gate_ctrl)
439 		fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */
440 
441 	return fe;
442 }
443 EXPORT_SYMBOL_GPL(mt2060_attach);
444 
445 static int mt2060_probe(struct i2c_client *client)
446 {
447 	struct mt2060_platform_data *pdata = client->dev.platform_data;
448 	struct dvb_frontend *fe;
449 	struct mt2060_priv *dev;
450 	int ret;
451 	u8 chip_id;
452 
453 	dev_dbg(&client->dev, "\n");
454 
455 	if (!pdata) {
456 		dev_err(&client->dev, "Cannot proceed without platform data\n");
457 		ret = -EINVAL;
458 		goto err;
459 	}
460 
461 	dev = devm_kzalloc(&client->dev, sizeof(*dev), GFP_KERNEL);
462 	if (!dev) {
463 		ret = -ENOMEM;
464 		goto err;
465 	}
466 
467 	fe = pdata->dvb_frontend;
468 	dev->config.i2c_address = client->addr;
469 	dev->config.clock_out = pdata->clock_out;
470 	dev->cfg = &dev->config;
471 	dev->i2c = client->adapter;
472 	dev->if1_freq = pdata->if1 ? pdata->if1 : 1220;
473 	dev->client = client;
474 	dev->i2c_max_regs = pdata->i2c_write_max ? pdata->i2c_write_max - 1 : ~0;
475 	dev->sleep = true;
476 
477 	ret = mt2060_readreg(dev, REG_PART_REV, &chip_id);
478 	if (ret) {
479 		ret = -ENODEV;
480 		goto err;
481 	}
482 
483 	dev_dbg(&client->dev, "chip id=%02x\n", chip_id);
484 
485 	if (chip_id != PART_REV) {
486 		ret = -ENODEV;
487 		goto err;
488 	}
489 
490 	/* Power on, calibrate, sleep */
491 	ret = mt2060_writereg(dev, REG_MISC_CTRL, 0x20);
492 	if (ret)
493 		goto err;
494 	mt2060_calibrate(dev);
495 	ret = mt2060_writereg(dev, REG_MISC_CTRL, 0xe8);
496 	if (ret)
497 		goto err;
498 
499 	dev_info(&client->dev, "Microtune MT2060 successfully identified\n");
500 	memcpy(&fe->ops.tuner_ops, &mt2060_tuner_ops, sizeof(fe->ops.tuner_ops));
501 	fe->ops.tuner_ops.release = NULL;
502 	fe->tuner_priv = dev;
503 	i2c_set_clientdata(client, dev);
504 
505 	return 0;
506 err:
507 	dev_dbg(&client->dev, "failed=%d\n", ret);
508 	return ret;
509 }
510 
511 static void mt2060_remove(struct i2c_client *client)
512 {
513 	dev_dbg(&client->dev, "\n");
514 }
515 
516 static const struct i2c_device_id mt2060_id_table[] = {
517 	{"mt2060", 0},
518 	{}
519 };
520 MODULE_DEVICE_TABLE(i2c, mt2060_id_table);
521 
522 static struct i2c_driver mt2060_driver = {
523 	.driver = {
524 		.name = "mt2060",
525 		.suppress_bind_attrs = true,
526 	},
527 	.probe		= mt2060_probe,
528 	.remove		= mt2060_remove,
529 	.id_table	= mt2060_id_table,
530 };
531 
532 module_i2c_driver(mt2060_driver);
533 
534 MODULE_AUTHOR("Olivier DANET");
535 MODULE_DESCRIPTION("Microtune MT2060 silicon tuner driver");
536 MODULE_LICENSE("GPL");
537