1 /*
2  * stv6110.c
3  *
4  * Driver for ST STV6110 satellite tuner IC.
5  *
6  * Copyright (C) 2009 NetUP Inc.
7  * Copyright (C) 2009 Igor M. Liplianin <liplianin@netup.ru>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  *
18  * GNU General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with this program; if not, write to the Free Software
22  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23  */
24 
25 #include <linux/slab.h>
26 #include <linux/module.h>
27 #include <linux/dvb/frontend.h>
28 
29 #include <linux/types.h>
30 
31 #include "stv6110.h"
32 
33 static int debug;
34 
35 struct stv6110_priv {
36 	int i2c_address;
37 	struct i2c_adapter *i2c;
38 
39 	u32 mclk;
40 	u8 clk_div;
41 	u8 gain;
42 	u8 regs[8];
43 };
44 
45 #define dprintk(args...) \
46 	do { \
47 		if (debug) \
48 			printk(KERN_DEBUG args); \
49 	} while (0)
50 
51 static s32 abssub(s32 a, s32 b)
52 {
53 	if (a > b)
54 		return a - b;
55 	else
56 		return b - a;
57 };
58 
59 static int stv6110_release(struct dvb_frontend *fe)
60 {
61 	kfree(fe->tuner_priv);
62 	fe->tuner_priv = NULL;
63 	return 0;
64 }
65 
66 static int stv6110_write_regs(struct dvb_frontend *fe, u8 buf[],
67 							int start, int len)
68 {
69 	struct stv6110_priv *priv = fe->tuner_priv;
70 	int rc;
71 	u8 cmdbuf[len + 1];
72 	struct i2c_msg msg = {
73 		.addr	= priv->i2c_address,
74 		.flags	= 0,
75 		.buf	= cmdbuf,
76 		.len	= len + 1
77 	};
78 
79 	dprintk("%s\n", __func__);
80 
81 	if (start + len > 8)
82 		return -EINVAL;
83 
84 	memcpy(&cmdbuf[1], buf, len);
85 	cmdbuf[0] = start;
86 
87 	if (fe->ops.i2c_gate_ctrl)
88 		fe->ops.i2c_gate_ctrl(fe, 1);
89 
90 	rc = i2c_transfer(priv->i2c, &msg, 1);
91 	if (rc != 1)
92 		dprintk("%s: i2c error\n", __func__);
93 
94 	if (fe->ops.i2c_gate_ctrl)
95 		fe->ops.i2c_gate_ctrl(fe, 0);
96 
97 	return 0;
98 }
99 
100 static int stv6110_read_regs(struct dvb_frontend *fe, u8 regs[],
101 							int start, int len)
102 {
103 	struct stv6110_priv *priv = fe->tuner_priv;
104 	int rc;
105 	u8 reg[] = { start };
106 	struct i2c_msg msg[] = {
107 		{
108 			.addr	= priv->i2c_address,
109 			.flags	= 0,
110 			.buf	= reg,
111 			.len	= 1,
112 		}, {
113 			.addr	= priv->i2c_address,
114 			.flags	= I2C_M_RD,
115 			.buf	= regs,
116 			.len	= len,
117 		},
118 	};
119 
120 	if (fe->ops.i2c_gate_ctrl)
121 		fe->ops.i2c_gate_ctrl(fe, 1);
122 
123 	rc = i2c_transfer(priv->i2c, msg, 2);
124 	if (rc != 2)
125 		dprintk("%s: i2c error\n", __func__);
126 
127 	if (fe->ops.i2c_gate_ctrl)
128 		fe->ops.i2c_gate_ctrl(fe, 0);
129 
130 	memcpy(&priv->regs[start], regs, len);
131 
132 	return 0;
133 }
134 
135 static int stv6110_read_reg(struct dvb_frontend *fe, int start)
136 {
137 	u8 buf[] = { 0 };
138 	stv6110_read_regs(fe, buf, start, 1);
139 
140 	return buf[0];
141 }
142 
143 static int stv6110_sleep(struct dvb_frontend *fe)
144 {
145 	u8 reg[] = { 0 };
146 	stv6110_write_regs(fe, reg, 0, 1);
147 
148 	return 0;
149 }
150 
151 static u32 carrier_width(u32 symbol_rate, fe_rolloff_t rolloff)
152 {
153 	u32 rlf;
154 
155 	switch (rolloff) {
156 	case ROLLOFF_20:
157 		rlf = 20;
158 		break;
159 	case ROLLOFF_25:
160 		rlf = 25;
161 		break;
162 	default:
163 		rlf = 35;
164 		break;
165 	}
166 
167 	return symbol_rate  + ((symbol_rate * rlf) / 100);
168 }
169 
170 static int stv6110_set_bandwidth(struct dvb_frontend *fe, u32 bandwidth)
171 {
172 	struct stv6110_priv *priv = fe->tuner_priv;
173 	u8 r8, ret = 0x04;
174 	int i;
175 
176 	if ((bandwidth / 2) > 36000000) /*BW/2 max=31+5=36 mhz for r8=31*/
177 		r8 = 31;
178 	else if ((bandwidth / 2) < 5000000) /* BW/2 min=5Mhz for F=0 */
179 		r8 = 0;
180 	else /*if 5 < BW/2 < 36*/
181 		r8 = (bandwidth / 2) / 1000000 - 5;
182 
183 	/* ctrl3, RCCLKOFF = 0 Activate the calibration Clock */
184 	/* ctrl3, CF = r8 Set the LPF value */
185 	priv->regs[RSTV6110_CTRL3] &= ~((1 << 6) | 0x1f);
186 	priv->regs[RSTV6110_CTRL3] |= (r8 & 0x1f);
187 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL3], RSTV6110_CTRL3, 1);
188 	/* stat1, CALRCSTRT = 1 Start LPF auto calibration*/
189 	priv->regs[RSTV6110_STAT1] |= 0x02;
190 	stv6110_write_regs(fe, &priv->regs[RSTV6110_STAT1], RSTV6110_STAT1, 1);
191 
192 	i = 0;
193 	/* Wait for CALRCSTRT == 0 */
194 	while ((i < 10) && (ret != 0)) {
195 		ret = ((stv6110_read_reg(fe, RSTV6110_STAT1)) & 0x02);
196 		mdelay(1);	/* wait for LPF auto calibration */
197 		i++;
198 	}
199 
200 	/* RCCLKOFF = 1 calibration done, desactivate the calibration Clock */
201 	priv->regs[RSTV6110_CTRL3] |= (1 << 6);
202 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL3], RSTV6110_CTRL3, 1);
203 	return 0;
204 }
205 
206 static int stv6110_init(struct dvb_frontend *fe)
207 {
208 	struct stv6110_priv *priv = fe->tuner_priv;
209 	u8 buf0[] = { 0x07, 0x11, 0xdc, 0x85, 0x17, 0x01, 0xe6, 0x1e };
210 
211 	memcpy(priv->regs, buf0, 8);
212 	/* K = (Reference / 1000000) - 16 */
213 	priv->regs[RSTV6110_CTRL1] &= ~(0x1f << 3);
214 	priv->regs[RSTV6110_CTRL1] |=
215 				((((priv->mclk / 1000000) - 16) & 0x1f) << 3);
216 
217 	/* divisor value for the output clock */
218 	priv->regs[RSTV6110_CTRL2] &= ~0xc0;
219 	priv->regs[RSTV6110_CTRL2] |= (priv->clk_div << 6);
220 
221 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL1], RSTV6110_CTRL1, 8);
222 	msleep(1);
223 	stv6110_set_bandwidth(fe, 72000000);
224 
225 	return 0;
226 }
227 
228 static int stv6110_get_frequency(struct dvb_frontend *fe, u32 *frequency)
229 {
230 	struct stv6110_priv *priv = fe->tuner_priv;
231 	u32 nbsteps, divider, psd2, freq;
232 	u8 regs[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
233 
234 	stv6110_read_regs(fe, regs, 0, 8);
235 	/*N*/
236 	divider = (priv->regs[RSTV6110_TUNING2] & 0x0f) << 8;
237 	divider += priv->regs[RSTV6110_TUNING1];
238 
239 	/*R*/
240 	nbsteps  = (priv->regs[RSTV6110_TUNING2] >> 6) & 3;
241 	/*p*/
242 	psd2  = (priv->regs[RSTV6110_TUNING2] >> 4) & 1;
243 
244 	freq = divider * (priv->mclk / 1000);
245 	freq /= (1 << (nbsteps + psd2));
246 	freq /= 4;
247 
248 	*frequency = freq;
249 
250 	return 0;
251 }
252 
253 static int stv6110_set_frequency(struct dvb_frontend *fe, u32 frequency)
254 {
255 	struct stv6110_priv *priv = fe->tuner_priv;
256 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
257 	u8 ret = 0x04;
258 	u32 divider, ref, p, presc, i, result_freq, vco_freq;
259 	s32 p_calc, p_calc_opt = 1000, r_div, r_div_opt = 0, p_val;
260 	s32 srate;
261 
262 	dprintk("%s, freq=%d kHz, mclk=%d Hz\n", __func__,
263 						frequency, priv->mclk);
264 
265 	/* K = (Reference / 1000000) - 16 */
266 	priv->regs[RSTV6110_CTRL1] &= ~(0x1f << 3);
267 	priv->regs[RSTV6110_CTRL1] |=
268 				((((priv->mclk / 1000000) - 16) & 0x1f) << 3);
269 
270 	/* BB_GAIN = db/2 */
271 	if (fe->ops.set_property && fe->ops.get_property) {
272 		srate = c->symbol_rate;
273 		dprintk("%s: Get Frontend parameters: srate=%d\n",
274 							__func__, srate);
275 	} else
276 		srate = 15000000;
277 
278 	priv->regs[RSTV6110_CTRL2] &= ~0x0f;
279 	priv->regs[RSTV6110_CTRL2] |= (priv->gain & 0x0f);
280 
281 	if (frequency <= 1023000) {
282 		p = 1;
283 		presc = 0;
284 	} else if (frequency <= 1300000) {
285 		p = 1;
286 		presc = 1;
287 	} else if (frequency <= 2046000) {
288 		p = 0;
289 		presc = 0;
290 	} else {
291 		p = 0;
292 		presc = 1;
293 	}
294 	/* DIV4SEL = p*/
295 	priv->regs[RSTV6110_TUNING2] &= ~(1 << 4);
296 	priv->regs[RSTV6110_TUNING2] |= (p << 4);
297 
298 	/* PRESC32ON = presc */
299 	priv->regs[RSTV6110_TUNING2] &= ~(1 << 5);
300 	priv->regs[RSTV6110_TUNING2] |= (presc << 5);
301 
302 	p_val = (int)(1 << (p + 1)) * 10;/* P = 2 or P = 4 */
303 	for (r_div = 0; r_div <= 3; r_div++) {
304 		p_calc = (priv->mclk / 100000);
305 		p_calc /= (1 << (r_div + 1));
306 		if ((abssub(p_calc, p_val)) < (abssub(p_calc_opt, p_val)))
307 			r_div_opt = r_div;
308 
309 		p_calc_opt = (priv->mclk / 100000);
310 		p_calc_opt /= (1 << (r_div_opt + 1));
311 	}
312 
313 	ref = priv->mclk / ((1 << (r_div_opt + 1))  * (1 << (p + 1)));
314 	divider = (((frequency * 1000) + (ref >> 1)) / ref);
315 
316 	/* RDIV = r_div_opt */
317 	priv->regs[RSTV6110_TUNING2] &= ~(3 << 6);
318 	priv->regs[RSTV6110_TUNING2] |= (((r_div_opt) & 3) << 6);
319 
320 	/* NDIV_MSB = MSB(divider) */
321 	priv->regs[RSTV6110_TUNING2] &= ~0x0f;
322 	priv->regs[RSTV6110_TUNING2] |= (((divider) >> 8) & 0x0f);
323 
324 	/* NDIV_LSB, LSB(divider) */
325 	priv->regs[RSTV6110_TUNING1] = (divider & 0xff);
326 
327 	/* CALVCOSTRT = 1 VCO Auto Calibration */
328 	priv->regs[RSTV6110_STAT1] |= 0x04;
329 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL1],
330 						RSTV6110_CTRL1, 8);
331 
332 	i = 0;
333 	/* Wait for CALVCOSTRT == 0 */
334 	while ((i < 10) && (ret != 0)) {
335 		ret = ((stv6110_read_reg(fe, RSTV6110_STAT1)) & 0x04);
336 		msleep(1); /* wait for VCO auto calibration */
337 		i++;
338 	}
339 
340 	ret = stv6110_read_reg(fe, RSTV6110_STAT1);
341 	stv6110_get_frequency(fe, &result_freq);
342 
343 	vco_freq = divider * ((priv->mclk / 1000) / ((1 << (r_div_opt + 1))));
344 	dprintk("%s, stat1=%x, lo_freq=%d kHz, vco_frec=%d kHz\n", __func__,
345 						ret, result_freq, vco_freq);
346 
347 	return 0;
348 }
349 
350 static int stv6110_set_params(struct dvb_frontend *fe)
351 {
352 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
353 	u32 bandwidth = carrier_width(c->symbol_rate, c->rolloff);
354 
355 	stv6110_set_frequency(fe, c->frequency);
356 	stv6110_set_bandwidth(fe, bandwidth);
357 
358 	return 0;
359 }
360 
361 static int stv6110_get_bandwidth(struct dvb_frontend *fe, u32 *bandwidth)
362 {
363 	struct stv6110_priv *priv = fe->tuner_priv;
364 	u8 r8 = 0;
365 	u8 regs[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
366 	stv6110_read_regs(fe, regs, 0, 8);
367 
368 	/* CF */
369 	r8 = priv->regs[RSTV6110_CTRL3] & 0x1f;
370 	*bandwidth = (r8 + 5) * 2000000;/* x2 for ZIF tuner BW/2 = F+5 Mhz */
371 
372 	return 0;
373 }
374 
375 static struct dvb_tuner_ops stv6110_tuner_ops = {
376 	.info = {
377 		.name = "ST STV6110",
378 		.frequency_min = 950000,
379 		.frequency_max = 2150000,
380 		.frequency_step = 1000,
381 	},
382 	.init = stv6110_init,
383 	.release = stv6110_release,
384 	.sleep = stv6110_sleep,
385 	.set_params = stv6110_set_params,
386 	.get_frequency = stv6110_get_frequency,
387 	.set_frequency = stv6110_set_frequency,
388 	.get_bandwidth = stv6110_get_bandwidth,
389 	.set_bandwidth = stv6110_set_bandwidth,
390 
391 };
392 
393 struct dvb_frontend *stv6110_attach(struct dvb_frontend *fe,
394 					const struct stv6110_config *config,
395 					struct i2c_adapter *i2c)
396 {
397 	struct stv6110_priv *priv = NULL;
398 	u8 reg0[] = { 0x00, 0x07, 0x11, 0xdc, 0x85, 0x17, 0x01, 0xe6, 0x1e };
399 
400 	struct i2c_msg msg[] = {
401 		{
402 			.addr = config->i2c_address,
403 			.flags = 0,
404 			.buf = reg0,
405 			.len = 9
406 		}
407 	};
408 	int ret;
409 
410 	/* divisor value for the output clock */
411 	reg0[2] &= ~0xc0;
412 	reg0[2] |= (config->clk_div << 6);
413 
414 	if (fe->ops.i2c_gate_ctrl)
415 		fe->ops.i2c_gate_ctrl(fe, 1);
416 
417 	ret = i2c_transfer(i2c, msg, 1);
418 
419 	if (fe->ops.i2c_gate_ctrl)
420 		fe->ops.i2c_gate_ctrl(fe, 0);
421 
422 	if (ret != 1)
423 		return NULL;
424 
425 	priv = kzalloc(sizeof(struct stv6110_priv), GFP_KERNEL);
426 	if (priv == NULL)
427 		return NULL;
428 
429 	priv->i2c_address = config->i2c_address;
430 	priv->i2c = i2c;
431 	priv->mclk = config->mclk;
432 	priv->clk_div = config->clk_div;
433 	priv->gain = config->gain;
434 
435 	memcpy(&priv->regs, &reg0[1], 8);
436 
437 	memcpy(&fe->ops.tuner_ops, &stv6110_tuner_ops,
438 				sizeof(struct dvb_tuner_ops));
439 	fe->tuner_priv = priv;
440 	printk(KERN_INFO "STV6110 attached on addr=%x!\n", priv->i2c_address);
441 
442 	return fe;
443 }
444 EXPORT_SYMBOL(stv6110_attach);
445 
446 module_param(debug, int, 0644);
447 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
448 
449 MODULE_DESCRIPTION("ST STV6110 driver");
450 MODULE_AUTHOR("Igor M. Liplianin");
451 MODULE_LICENSE("GPL");
452