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 /* Max transfer size done by I2C transfer functions */
34 #define MAX_XFER_SIZE  64
35 
36 static int debug;
37 
38 struct stv6110_priv {
39 	int i2c_address;
40 	struct i2c_adapter *i2c;
41 
42 	u32 mclk;
43 	u8 clk_div;
44 	u8 gain;
45 	u8 regs[8];
46 };
47 
48 #define dprintk(args...) \
49 	do { \
50 		if (debug) \
51 			printk(KERN_DEBUG args); \
52 	} while (0)
53 
54 static s32 abssub(s32 a, s32 b)
55 {
56 	if (a > b)
57 		return a - b;
58 	else
59 		return b - a;
60 };
61 
62 static int stv6110_release(struct dvb_frontend *fe)
63 {
64 	kfree(fe->tuner_priv);
65 	fe->tuner_priv = NULL;
66 	return 0;
67 }
68 
69 static int stv6110_write_regs(struct dvb_frontend *fe, u8 buf[],
70 							int start, int len)
71 {
72 	struct stv6110_priv *priv = fe->tuner_priv;
73 	int rc;
74 	u8 cmdbuf[MAX_XFER_SIZE];
75 	struct i2c_msg msg = {
76 		.addr	= priv->i2c_address,
77 		.flags	= 0,
78 		.buf	= cmdbuf,
79 		.len	= len + 1
80 	};
81 
82 	dprintk("%s\n", __func__);
83 
84 	if (1 + len > sizeof(cmdbuf)) {
85 		printk(KERN_WARNING
86 		       "%s: i2c wr: len=%d is too big!\n",
87 		       KBUILD_MODNAME, len);
88 		return -EINVAL;
89 	}
90 
91 	if (start + len > 8)
92 		return -EINVAL;
93 
94 	memcpy(&cmdbuf[1], buf, len);
95 	cmdbuf[0] = start;
96 
97 	if (fe->ops.i2c_gate_ctrl)
98 		fe->ops.i2c_gate_ctrl(fe, 1);
99 
100 	rc = i2c_transfer(priv->i2c, &msg, 1);
101 	if (rc != 1)
102 		dprintk("%s: i2c error\n", __func__);
103 
104 	if (fe->ops.i2c_gate_ctrl)
105 		fe->ops.i2c_gate_ctrl(fe, 0);
106 
107 	return 0;
108 }
109 
110 static int stv6110_read_regs(struct dvb_frontend *fe, u8 regs[],
111 							int start, int len)
112 {
113 	struct stv6110_priv *priv = fe->tuner_priv;
114 	int rc;
115 	u8 reg[] = { start };
116 	struct i2c_msg msg[] = {
117 		{
118 			.addr	= priv->i2c_address,
119 			.flags	= 0,
120 			.buf	= reg,
121 			.len	= 1,
122 		}, {
123 			.addr	= priv->i2c_address,
124 			.flags	= I2C_M_RD,
125 			.buf	= regs,
126 			.len	= len,
127 		},
128 	};
129 
130 	if (fe->ops.i2c_gate_ctrl)
131 		fe->ops.i2c_gate_ctrl(fe, 1);
132 
133 	rc = i2c_transfer(priv->i2c, msg, 2);
134 	if (rc != 2)
135 		dprintk("%s: i2c error\n", __func__);
136 
137 	if (fe->ops.i2c_gate_ctrl)
138 		fe->ops.i2c_gate_ctrl(fe, 0);
139 
140 	memcpy(&priv->regs[start], regs, len);
141 
142 	return 0;
143 }
144 
145 static int stv6110_read_reg(struct dvb_frontend *fe, int start)
146 {
147 	u8 buf[] = { 0 };
148 	stv6110_read_regs(fe, buf, start, 1);
149 
150 	return buf[0];
151 }
152 
153 static int stv6110_sleep(struct dvb_frontend *fe)
154 {
155 	u8 reg[] = { 0 };
156 	stv6110_write_regs(fe, reg, 0, 1);
157 
158 	return 0;
159 }
160 
161 static u32 carrier_width(u32 symbol_rate, enum fe_rolloff rolloff)
162 {
163 	u32 rlf;
164 
165 	switch (rolloff) {
166 	case ROLLOFF_20:
167 		rlf = 20;
168 		break;
169 	case ROLLOFF_25:
170 		rlf = 25;
171 		break;
172 	default:
173 		rlf = 35;
174 		break;
175 	}
176 
177 	return symbol_rate  + ((symbol_rate * rlf) / 100);
178 }
179 
180 static int stv6110_set_bandwidth(struct dvb_frontend *fe, u32 bandwidth)
181 {
182 	struct stv6110_priv *priv = fe->tuner_priv;
183 	u8 r8, ret = 0x04;
184 	int i;
185 
186 	if ((bandwidth / 2) > 36000000) /*BW/2 max=31+5=36 mhz for r8=31*/
187 		r8 = 31;
188 	else if ((bandwidth / 2) < 5000000) /* BW/2 min=5Mhz for F=0 */
189 		r8 = 0;
190 	else /*if 5 < BW/2 < 36*/
191 		r8 = (bandwidth / 2) / 1000000 - 5;
192 
193 	/* ctrl3, RCCLKOFF = 0 Activate the calibration Clock */
194 	/* ctrl3, CF = r8 Set the LPF value */
195 	priv->regs[RSTV6110_CTRL3] &= ~((1 << 6) | 0x1f);
196 	priv->regs[RSTV6110_CTRL3] |= (r8 & 0x1f);
197 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL3], RSTV6110_CTRL3, 1);
198 	/* stat1, CALRCSTRT = 1 Start LPF auto calibration*/
199 	priv->regs[RSTV6110_STAT1] |= 0x02;
200 	stv6110_write_regs(fe, &priv->regs[RSTV6110_STAT1], RSTV6110_STAT1, 1);
201 
202 	i = 0;
203 	/* Wait for CALRCSTRT == 0 */
204 	while ((i < 10) && (ret != 0)) {
205 		ret = ((stv6110_read_reg(fe, RSTV6110_STAT1)) & 0x02);
206 		mdelay(1);	/* wait for LPF auto calibration */
207 		i++;
208 	}
209 
210 	/* RCCLKOFF = 1 calibration done, desactivate the calibration Clock */
211 	priv->regs[RSTV6110_CTRL3] |= (1 << 6);
212 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL3], RSTV6110_CTRL3, 1);
213 	return 0;
214 }
215 
216 static int stv6110_init(struct dvb_frontend *fe)
217 {
218 	struct stv6110_priv *priv = fe->tuner_priv;
219 	u8 buf0[] = { 0x07, 0x11, 0xdc, 0x85, 0x17, 0x01, 0xe6, 0x1e };
220 
221 	memcpy(priv->regs, buf0, 8);
222 	/* K = (Reference / 1000000) - 16 */
223 	priv->regs[RSTV6110_CTRL1] &= ~(0x1f << 3);
224 	priv->regs[RSTV6110_CTRL1] |=
225 				((((priv->mclk / 1000000) - 16) & 0x1f) << 3);
226 
227 	/* divisor value for the output clock */
228 	priv->regs[RSTV6110_CTRL2] &= ~0xc0;
229 	priv->regs[RSTV6110_CTRL2] |= (priv->clk_div << 6);
230 
231 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL1], RSTV6110_CTRL1, 8);
232 	msleep(1);
233 	stv6110_set_bandwidth(fe, 72000000);
234 
235 	return 0;
236 }
237 
238 static int stv6110_get_frequency(struct dvb_frontend *fe, u32 *frequency)
239 {
240 	struct stv6110_priv *priv = fe->tuner_priv;
241 	u32 nbsteps, divider, psd2, freq;
242 	u8 regs[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
243 
244 	stv6110_read_regs(fe, regs, 0, 8);
245 	/*N*/
246 	divider = (priv->regs[RSTV6110_TUNING2] & 0x0f) << 8;
247 	divider += priv->regs[RSTV6110_TUNING1];
248 
249 	/*R*/
250 	nbsteps  = (priv->regs[RSTV6110_TUNING2] >> 6) & 3;
251 	/*p*/
252 	psd2  = (priv->regs[RSTV6110_TUNING2] >> 4) & 1;
253 
254 	freq = divider * (priv->mclk / 1000);
255 	freq /= (1 << (nbsteps + psd2));
256 	freq /= 4;
257 
258 	*frequency = freq;
259 
260 	return 0;
261 }
262 
263 static int stv6110_set_frequency(struct dvb_frontend *fe, u32 frequency)
264 {
265 	struct stv6110_priv *priv = fe->tuner_priv;
266 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
267 	u8 ret = 0x04;
268 	u32 divider, ref, p, presc, i, result_freq, vco_freq;
269 	s32 p_calc, p_calc_opt = 1000, r_div, r_div_opt = 0, p_val;
270 	s32 srate;
271 
272 	dprintk("%s, freq=%d kHz, mclk=%d Hz\n", __func__,
273 						frequency, priv->mclk);
274 
275 	/* K = (Reference / 1000000) - 16 */
276 	priv->regs[RSTV6110_CTRL1] &= ~(0x1f << 3);
277 	priv->regs[RSTV6110_CTRL1] |=
278 				((((priv->mclk / 1000000) - 16) & 0x1f) << 3);
279 
280 	/* BB_GAIN = db/2 */
281 	if (fe->ops.set_property && fe->ops.get_property) {
282 		srate = c->symbol_rate;
283 		dprintk("%s: Get Frontend parameters: srate=%d\n",
284 							__func__, srate);
285 	} else
286 		srate = 15000000;
287 
288 	priv->regs[RSTV6110_CTRL2] &= ~0x0f;
289 	priv->regs[RSTV6110_CTRL2] |= (priv->gain & 0x0f);
290 
291 	if (frequency <= 1023000) {
292 		p = 1;
293 		presc = 0;
294 	} else if (frequency <= 1300000) {
295 		p = 1;
296 		presc = 1;
297 	} else if (frequency <= 2046000) {
298 		p = 0;
299 		presc = 0;
300 	} else {
301 		p = 0;
302 		presc = 1;
303 	}
304 	/* DIV4SEL = p*/
305 	priv->regs[RSTV6110_TUNING2] &= ~(1 << 4);
306 	priv->regs[RSTV6110_TUNING2] |= (p << 4);
307 
308 	/* PRESC32ON = presc */
309 	priv->regs[RSTV6110_TUNING2] &= ~(1 << 5);
310 	priv->regs[RSTV6110_TUNING2] |= (presc << 5);
311 
312 	p_val = (int)(1 << (p + 1)) * 10;/* P = 2 or P = 4 */
313 	for (r_div = 0; r_div <= 3; r_div++) {
314 		p_calc = (priv->mclk / 100000);
315 		p_calc /= (1 << (r_div + 1));
316 		if ((abssub(p_calc, p_val)) < (abssub(p_calc_opt, p_val)))
317 			r_div_opt = r_div;
318 
319 		p_calc_opt = (priv->mclk / 100000);
320 		p_calc_opt /= (1 << (r_div_opt + 1));
321 	}
322 
323 	ref = priv->mclk / ((1 << (r_div_opt + 1))  * (1 << (p + 1)));
324 	divider = (((frequency * 1000) + (ref >> 1)) / ref);
325 
326 	/* RDIV = r_div_opt */
327 	priv->regs[RSTV6110_TUNING2] &= ~(3 << 6);
328 	priv->regs[RSTV6110_TUNING2] |= (((r_div_opt) & 3) << 6);
329 
330 	/* NDIV_MSB = MSB(divider) */
331 	priv->regs[RSTV6110_TUNING2] &= ~0x0f;
332 	priv->regs[RSTV6110_TUNING2] |= (((divider) >> 8) & 0x0f);
333 
334 	/* NDIV_LSB, LSB(divider) */
335 	priv->regs[RSTV6110_TUNING1] = (divider & 0xff);
336 
337 	/* CALVCOSTRT = 1 VCO Auto Calibration */
338 	priv->regs[RSTV6110_STAT1] |= 0x04;
339 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL1],
340 						RSTV6110_CTRL1, 8);
341 
342 	i = 0;
343 	/* Wait for CALVCOSTRT == 0 */
344 	while ((i < 10) && (ret != 0)) {
345 		ret = ((stv6110_read_reg(fe, RSTV6110_STAT1)) & 0x04);
346 		msleep(1); /* wait for VCO auto calibration */
347 		i++;
348 	}
349 
350 	ret = stv6110_read_reg(fe, RSTV6110_STAT1);
351 	stv6110_get_frequency(fe, &result_freq);
352 
353 	vco_freq = divider * ((priv->mclk / 1000) / ((1 << (r_div_opt + 1))));
354 	dprintk("%s, stat1=%x, lo_freq=%d kHz, vco_frec=%d kHz\n", __func__,
355 						ret, result_freq, vco_freq);
356 
357 	return 0;
358 }
359 
360 static int stv6110_set_params(struct dvb_frontend *fe)
361 {
362 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
363 	u32 bandwidth = carrier_width(c->symbol_rate, c->rolloff);
364 
365 	stv6110_set_frequency(fe, c->frequency);
366 	stv6110_set_bandwidth(fe, bandwidth);
367 
368 	return 0;
369 }
370 
371 static int stv6110_get_bandwidth(struct dvb_frontend *fe, u32 *bandwidth)
372 {
373 	struct stv6110_priv *priv = fe->tuner_priv;
374 	u8 r8 = 0;
375 	u8 regs[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
376 	stv6110_read_regs(fe, regs, 0, 8);
377 
378 	/* CF */
379 	r8 = priv->regs[RSTV6110_CTRL3] & 0x1f;
380 	*bandwidth = (r8 + 5) * 2000000;/* x2 for ZIF tuner BW/2 = F+5 Mhz */
381 
382 	return 0;
383 }
384 
385 static struct dvb_tuner_ops stv6110_tuner_ops = {
386 	.info = {
387 		.name = "ST STV6110",
388 		.frequency_min = 950000,
389 		.frequency_max = 2150000,
390 		.frequency_step = 1000,
391 	},
392 	.init = stv6110_init,
393 	.release = stv6110_release,
394 	.sleep = stv6110_sleep,
395 	.set_params = stv6110_set_params,
396 	.get_frequency = stv6110_get_frequency,
397 	.set_frequency = stv6110_set_frequency,
398 	.get_bandwidth = stv6110_get_bandwidth,
399 	.set_bandwidth = stv6110_set_bandwidth,
400 
401 };
402 
403 struct dvb_frontend *stv6110_attach(struct dvb_frontend *fe,
404 					const struct stv6110_config *config,
405 					struct i2c_adapter *i2c)
406 {
407 	struct stv6110_priv *priv = NULL;
408 	u8 reg0[] = { 0x00, 0x07, 0x11, 0xdc, 0x85, 0x17, 0x01, 0xe6, 0x1e };
409 
410 	struct i2c_msg msg[] = {
411 		{
412 			.addr = config->i2c_address,
413 			.flags = 0,
414 			.buf = reg0,
415 			.len = 9
416 		}
417 	};
418 	int ret;
419 
420 	/* divisor value for the output clock */
421 	reg0[2] &= ~0xc0;
422 	reg0[2] |= (config->clk_div << 6);
423 
424 	if (fe->ops.i2c_gate_ctrl)
425 		fe->ops.i2c_gate_ctrl(fe, 1);
426 
427 	ret = i2c_transfer(i2c, msg, 1);
428 
429 	if (fe->ops.i2c_gate_ctrl)
430 		fe->ops.i2c_gate_ctrl(fe, 0);
431 
432 	if (ret != 1)
433 		return NULL;
434 
435 	priv = kzalloc(sizeof(struct stv6110_priv), GFP_KERNEL);
436 	if (priv == NULL)
437 		return NULL;
438 
439 	priv->i2c_address = config->i2c_address;
440 	priv->i2c = i2c;
441 	priv->mclk = config->mclk;
442 	priv->clk_div = config->clk_div;
443 	priv->gain = config->gain;
444 
445 	memcpy(&priv->regs, &reg0[1], 8);
446 
447 	memcpy(&fe->ops.tuner_ops, &stv6110_tuner_ops,
448 				sizeof(struct dvb_tuner_ops));
449 	fe->tuner_priv = priv;
450 	printk(KERN_INFO "STV6110 attached on addr=%x!\n", priv->i2c_address);
451 
452 	return fe;
453 }
454 EXPORT_SYMBOL(stv6110_attach);
455 
456 module_param(debug, int, 0644);
457 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
458 
459 MODULE_DESCRIPTION("ST STV6110 driver");
460 MODULE_AUTHOR("Igor M. Liplianin");
461 MODULE_LICENSE("GPL");
462