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
21static int debug;
22module_param(debug, int, 0644);
23MODULE_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
28static 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
58static 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
84static 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
118static u8 mt2060_config1[] = {
119	REG_LO1C1,
120	0x3F,	0x74,	0x00,	0x08,	0x93
121};
122
123// FMCG=2, GP2=0, GP1=0
124static 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 */
134static 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 */
153static 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
188static 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
277static 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
320static 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
327static int mt2060_get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
328{
329	*frequency = IF2 * 1000;
330	return 0;
331}
332
333static 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
350err_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
357static 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
373err_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
380static void mt2060_release(struct dvb_frontend *fe)
381{
382	kfree(fe->tuner_priv);
383	fe->tuner_priv = NULL;
384}
385
386static 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. */
405struct 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}
443EXPORT_SYMBOL_GPL(mt2060_attach);
444
445static 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;
506err:
507	dev_dbg(&client->dev, "failed=%d\n", ret);
508	return ret;
509}
510
511static void mt2060_remove(struct i2c_client *client)
512{
513	dev_dbg(&client->dev, "\n");
514}
515
516static const struct i2c_device_id mt2060_id_table[] = {
517	{"mt2060", 0},
518	{}
519};
520MODULE_DEVICE_TABLE(i2c, mt2060_id_table);
521
522static 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
532module_i2c_driver(mt2060_driver);
533
534MODULE_AUTHOR("Olivier DANET");
535MODULE_DESCRIPTION("Microtune MT2060 silicon tuner driver");
536MODULE_LICENSE("GPL");
537