xref: /openbmc/linux/drivers/media/tuners/mt2060.c (revision 275876e2)
1 /*
2  *  Driver for Microtune MT2060 "Single chip dual conversion broadband tuner"
3  *
4  *  Copyright (c) 2006 Olivier DANET <odanet@caramail.com>
5  *
6  *  This program is free software; you can redistribute it and/or modify
7  *  it under the terms of the GNU General Public License as published by
8  *  the Free Software Foundation; either version 2 of the License, or
9  *  (at your option) any later version.
10  *
11  *  This program is distributed in the hope that it will be useful,
12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, write to the Free Software
19  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.=
20  */
21 
22 /* In that file, frequencies are expressed in kiloHertz to avoid 32 bits overflows */
23 
24 #include <linux/module.h>
25 #include <linux/delay.h>
26 #include <linux/dvb/frontend.h>
27 #include <linux/i2c.h>
28 #include <linux/slab.h>
29 
30 #include "dvb_frontend.h"
31 
32 #include "mt2060.h"
33 #include "mt2060_priv.h"
34 
35 static int debug;
36 module_param(debug, int, 0644);
37 MODULE_PARM_DESC(debug, "Turn on/off debugging (default:off).");
38 
39 #define dprintk(args...) do { if (debug) {printk(KERN_DEBUG "MT2060: " args); printk("\n"); }} while (0)
40 
41 // Reads a single register
42 static int mt2060_readreg(struct mt2060_priv *priv, u8 reg, u8 *val)
43 {
44 	struct i2c_msg msg[2] = {
45 		{ .addr = priv->cfg->i2c_address, .flags = 0,        .buf = &reg, .len = 1 },
46 		{ .addr = priv->cfg->i2c_address, .flags = I2C_M_RD, .buf = val,  .len = 1 },
47 	};
48 
49 	if (i2c_transfer(priv->i2c, msg, 2) != 2) {
50 		printk(KERN_WARNING "mt2060 I2C read failed\n");
51 		return -EREMOTEIO;
52 	}
53 	return 0;
54 }
55 
56 // Writes a single register
57 static int mt2060_writereg(struct mt2060_priv *priv, u8 reg, u8 val)
58 {
59 	u8 buf[2] = { reg, val };
60 	struct i2c_msg msg = {
61 		.addr = priv->cfg->i2c_address, .flags = 0, .buf = buf, .len = 2
62 	};
63 
64 	if (i2c_transfer(priv->i2c, &msg, 1) != 1) {
65 		printk(KERN_WARNING "mt2060 I2C write failed\n");
66 		return -EREMOTEIO;
67 	}
68 	return 0;
69 }
70 
71 // Writes a set of consecutive registers
72 static int mt2060_writeregs(struct mt2060_priv *priv,u8 *buf, u8 len)
73 {
74 	struct i2c_msg msg = {
75 		.addr = priv->cfg->i2c_address, .flags = 0, .buf = buf, .len = len
76 	};
77 	if (i2c_transfer(priv->i2c, &msg, 1) != 1) {
78 		printk(KERN_WARNING "mt2060 I2C write failed (len=%i)\n",(int)len);
79 		return -EREMOTEIO;
80 	}
81 	return 0;
82 }
83 
84 // Initialisation sequences
85 // LNABAND=3, NUM1=0x3C, DIV1=0x74, NUM2=0x1080, DIV2=0x49
86 static u8 mt2060_config1[] = {
87 	REG_LO1C1,
88 	0x3F,	0x74,	0x00,	0x08,	0x93
89 };
90 
91 // FMCG=2, GP2=0, GP1=0
92 static u8 mt2060_config2[] = {
93 	REG_MISC_CTRL,
94 	0x20,	0x1E,	0x30,	0xff,	0x80,	0xff,	0x00,	0x2c,	0x42
95 };
96 
97 //  VGAG=3, V1CSE=1
98 
99 #ifdef  MT2060_SPURCHECK
100 /* The function below calculates the frequency offset between the output frequency if2
101  and the closer cross modulation subcarrier between lo1 and lo2 up to the tenth harmonic */
102 static int mt2060_spurcalc(u32 lo1,u32 lo2,u32 if2)
103 {
104 	int I,J;
105 	int dia,diamin,diff;
106 	diamin=1000000;
107 	for (I = 1; I < 10; I++) {
108 		J = ((2*I*lo1)/lo2+1)/2;
109 		diff = I*(int)lo1-J*(int)lo2;
110 		if (diff < 0) diff=-diff;
111 		dia = (diff-(int)if2);
112 		if (dia < 0) dia=-dia;
113 		if (diamin > dia) diamin=dia;
114 	}
115 	return diamin;
116 }
117 
118 #define BANDWIDTH 4000 // kHz
119 
120 /* Calculates the frequency offset to add to avoid spurs. Returns 0 if no offset is needed */
121 static int mt2060_spurcheck(u32 lo1,u32 lo2,u32 if2)
122 {
123 	u32 Spur,Sp1,Sp2;
124 	int I,J;
125 	I=0;
126 	J=1000;
127 
128 	Spur=mt2060_spurcalc(lo1,lo2,if2);
129 	if (Spur < BANDWIDTH) {
130 		/* Potential spurs detected */
131 		dprintk("Spurs before : f_lo1: %d  f_lo2: %d  (kHz)",
132 			(int)lo1,(int)lo2);
133 		I=1000;
134 		Sp1 = mt2060_spurcalc(lo1+I,lo2+I,if2);
135 		Sp2 = mt2060_spurcalc(lo1-I,lo2-I,if2);
136 
137 		if (Sp1 < Sp2) {
138 			J=-J; I=-I; Spur=Sp2;
139 		} else
140 			Spur=Sp1;
141 
142 		while (Spur < BANDWIDTH) {
143 			I += J;
144 			Spur = mt2060_spurcalc(lo1+I,lo2+I,if2);
145 		}
146 		dprintk("Spurs after  : f_lo1: %d  f_lo2: %d  (kHz)",
147 			(int)(lo1+I),(int)(lo2+I));
148 	}
149 	return I;
150 }
151 #endif
152 
153 #define IF2  36150       // IF2 frequency = 36.150 MHz
154 #define FREF 16000       // Quartz oscillator 16 MHz
155 
156 static int mt2060_set_params(struct dvb_frontend *fe)
157 {
158 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
159 	struct mt2060_priv *priv;
160 	int ret=0;
161 	int i=0;
162 	u32 freq;
163 	u8  lnaband;
164 	u32 f_lo1,f_lo2;
165 	u32 div1,num1,div2,num2;
166 	u8  b[8];
167 	u32 if1;
168 
169 	priv = fe->tuner_priv;
170 
171 	if1 = priv->if1_freq;
172 	b[0] = REG_LO1B1;
173 	b[1] = 0xFF;
174 
175 	if (fe->ops.i2c_gate_ctrl)
176 		fe->ops.i2c_gate_ctrl(fe, 1); /* open i2c_gate */
177 
178 	mt2060_writeregs(priv,b,2);
179 
180 	freq = c->frequency / 1000; /* Hz -> kHz */
181 
182 	f_lo1 = freq + if1 * 1000;
183 	f_lo1 = (f_lo1 / 250) * 250;
184 	f_lo2 = f_lo1 - freq - IF2;
185 	// From the Comtech datasheet, the step used is 50kHz. The tuner chip could be more precise
186 	f_lo2 = ((f_lo2 + 25) / 50) * 50;
187 	priv->frequency =  (f_lo1 - f_lo2 - IF2) * 1000,
188 
189 #ifdef MT2060_SPURCHECK
190 	// LO-related spurs detection and correction
191 	num1   = mt2060_spurcheck(f_lo1,f_lo2,IF2);
192 	f_lo1 += num1;
193 	f_lo2 += num1;
194 #endif
195 	//Frequency LO1 = 16MHz * (DIV1 + NUM1/64 )
196 	num1 = f_lo1 / (FREF / 64);
197 	div1 = num1 / 64;
198 	num1 &= 0x3f;
199 
200 	// Frequency LO2 = 16MHz * (DIV2 + NUM2/8192 )
201 	num2 = f_lo2 * 64 / (FREF / 128);
202 	div2 = num2 / 8192;
203 	num2 &= 0x1fff;
204 
205 	if (freq <=  95000) lnaband = 0xB0; else
206 	if (freq <= 180000) lnaband = 0xA0; else
207 	if (freq <= 260000) lnaband = 0x90; else
208 	if (freq <= 335000) lnaband = 0x80; else
209 	if (freq <= 425000) lnaband = 0x70; else
210 	if (freq <= 480000) lnaband = 0x60; else
211 	if (freq <= 570000) lnaband = 0x50; else
212 	if (freq <= 645000) lnaband = 0x40; else
213 	if (freq <= 730000) lnaband = 0x30; else
214 	if (freq <= 810000) lnaband = 0x20; else lnaband = 0x10;
215 
216 	b[0] = REG_LO1C1;
217 	b[1] = lnaband | ((num1 >>2) & 0x0F);
218 	b[2] = div1;
219 	b[3] = (num2 & 0x0F)  | ((num1 & 3) << 4);
220 	b[4] = num2 >> 4;
221 	b[5] = ((num2 >>12) & 1) | (div2 << 1);
222 
223 	dprintk("IF1: %dMHz",(int)if1);
224 	dprintk("PLL freq=%dkHz  f_lo1=%dkHz  f_lo2=%dkHz",(int)freq,(int)f_lo1,(int)f_lo2);
225 	dprintk("PLL div1=%d  num1=%d  div2=%d  num2=%d",(int)div1,(int)num1,(int)div2,(int)num2);
226 	dprintk("PLL [1..5]: %2x %2x %2x %2x %2x",(int)b[1],(int)b[2],(int)b[3],(int)b[4],(int)b[5]);
227 
228 	mt2060_writeregs(priv,b,6);
229 
230 	//Waits for pll lock or timeout
231 	i = 0;
232 	do {
233 		mt2060_readreg(priv,REG_LO_STATUS,b);
234 		if ((b[0] & 0x88)==0x88)
235 			break;
236 		msleep(4);
237 		i++;
238 	} while (i<10);
239 
240 	if (fe->ops.i2c_gate_ctrl)
241 		fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */
242 
243 	return ret;
244 }
245 
246 static void mt2060_calibrate(struct mt2060_priv *priv)
247 {
248 	u8 b = 0;
249 	int i = 0;
250 
251 	if (mt2060_writeregs(priv,mt2060_config1,sizeof(mt2060_config1)))
252 		return;
253 	if (mt2060_writeregs(priv,mt2060_config2,sizeof(mt2060_config2)))
254 		return;
255 
256 	/* initialize the clock output */
257 	mt2060_writereg(priv, REG_VGAG, (priv->cfg->clock_out << 6) | 0x30);
258 
259 	do {
260 		b |= (1 << 6); // FM1SS;
261 		mt2060_writereg(priv, REG_LO2C1,b);
262 		msleep(20);
263 
264 		if (i == 0) {
265 			b |= (1 << 7); // FM1CA;
266 			mt2060_writereg(priv, REG_LO2C1,b);
267 			b &= ~(1 << 7); // FM1CA;
268 			msleep(20);
269 		}
270 
271 		b &= ~(1 << 6); // FM1SS
272 		mt2060_writereg(priv, REG_LO2C1,b);
273 
274 		msleep(20);
275 		i++;
276 	} while (i < 9);
277 
278 	i = 0;
279 	while (i++ < 10 && mt2060_readreg(priv, REG_MISC_STAT, &b) == 0 && (b & (1 << 6)) == 0)
280 		msleep(20);
281 
282 	if (i <= 10) {
283 		mt2060_readreg(priv, REG_FM_FREQ, &priv->fmfreq); // now find out, what is fmreq used for :)
284 		dprintk("calibration was successful: %d", (int)priv->fmfreq);
285 	} else
286 		dprintk("FMCAL timed out");
287 }
288 
289 static int mt2060_get_frequency(struct dvb_frontend *fe, u32 *frequency)
290 {
291 	struct mt2060_priv *priv = fe->tuner_priv;
292 	*frequency = priv->frequency;
293 	return 0;
294 }
295 
296 static int mt2060_get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
297 {
298 	*frequency = IF2 * 1000;
299 	return 0;
300 }
301 
302 static int mt2060_init(struct dvb_frontend *fe)
303 {
304 	struct mt2060_priv *priv = fe->tuner_priv;
305 	int ret;
306 
307 	if (fe->ops.i2c_gate_ctrl)
308 		fe->ops.i2c_gate_ctrl(fe, 1); /* open i2c_gate */
309 
310 	ret = mt2060_writereg(priv, REG_VGAG,
311 			      (priv->cfg->clock_out << 6) | 0x33);
312 
313 	if (fe->ops.i2c_gate_ctrl)
314 		fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */
315 
316 	return ret;
317 }
318 
319 static int mt2060_sleep(struct dvb_frontend *fe)
320 {
321 	struct mt2060_priv *priv = fe->tuner_priv;
322 	int ret;
323 
324 	if (fe->ops.i2c_gate_ctrl)
325 		fe->ops.i2c_gate_ctrl(fe, 1); /* open i2c_gate */
326 
327 	ret = mt2060_writereg(priv, REG_VGAG,
328 			      (priv->cfg->clock_out << 6) | 0x30);
329 
330 	if (fe->ops.i2c_gate_ctrl)
331 		fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */
332 
333 	return ret;
334 }
335 
336 static int mt2060_release(struct dvb_frontend *fe)
337 {
338 	kfree(fe->tuner_priv);
339 	fe->tuner_priv = NULL;
340 	return 0;
341 }
342 
343 static const struct dvb_tuner_ops mt2060_tuner_ops = {
344 	.info = {
345 		.name           = "Microtune MT2060",
346 		.frequency_min  =  48000000,
347 		.frequency_max  = 860000000,
348 		.frequency_step =     50000,
349 	},
350 
351 	.release       = mt2060_release,
352 
353 	.init          = mt2060_init,
354 	.sleep         = mt2060_sleep,
355 
356 	.set_params    = mt2060_set_params,
357 	.get_frequency = mt2060_get_frequency,
358 	.get_if_frequency = mt2060_get_if_frequency,
359 };
360 
361 /* This functions tries to identify a MT2060 tuner by reading the PART/REV register. This is hasty. */
362 struct dvb_frontend * mt2060_attach(struct dvb_frontend *fe, struct i2c_adapter *i2c, struct mt2060_config *cfg, u16 if1)
363 {
364 	struct mt2060_priv *priv = NULL;
365 	u8 id = 0;
366 
367 	priv = kzalloc(sizeof(struct mt2060_priv), GFP_KERNEL);
368 	if (priv == NULL)
369 		return NULL;
370 
371 	priv->cfg      = cfg;
372 	priv->i2c      = i2c;
373 	priv->if1_freq = if1;
374 
375 	if (fe->ops.i2c_gate_ctrl)
376 		fe->ops.i2c_gate_ctrl(fe, 1); /* open i2c_gate */
377 
378 	if (mt2060_readreg(priv,REG_PART_REV,&id) != 0) {
379 		kfree(priv);
380 		return NULL;
381 	}
382 
383 	if (id != PART_REV) {
384 		kfree(priv);
385 		return NULL;
386 	}
387 	printk(KERN_INFO "MT2060: successfully identified (IF1 = %d)\n", if1);
388 	memcpy(&fe->ops.tuner_ops, &mt2060_tuner_ops, sizeof(struct dvb_tuner_ops));
389 
390 	fe->tuner_priv = priv;
391 
392 	mt2060_calibrate(priv);
393 
394 	if (fe->ops.i2c_gate_ctrl)
395 		fe->ops.i2c_gate_ctrl(fe, 0); /* close i2c_gate */
396 
397 	return fe;
398 }
399 EXPORT_SYMBOL(mt2060_attach);
400 
401 MODULE_AUTHOR("Olivier DANET");
402 MODULE_DESCRIPTION("Microtune MT2060 silicon tuner driver");
403 MODULE_LICENSE("GPL");
404