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 
21 #include <linux/slab.h>
22 #include <linux/module.h>
23 #include <linux/dvb/frontend.h>
24 
25 #include <linux/types.h>
26 
27 #include "stv6110.h"
28 
29 /* Max transfer size done by I2C transfer functions */
30 #define MAX_XFER_SIZE  64
31 
32 static int debug;
33 
34 struct stv6110_priv {
35 	int i2c_address;
36 	struct i2c_adapter *i2c;
37 
38 	u32 mclk;
39 	u8 clk_div;
40 	u8 gain;
41 	u8 regs[8];
42 };
43 
44 #define dprintk(args...) \
45 	do { \
46 		if (debug) \
47 			printk(KERN_DEBUG args); \
48 	} while (0)
49 
50 static s32 abssub(s32 a, s32 b)
51 {
52 	if (a > b)
53 		return a - b;
54 	else
55 		return b - a;
56 };
57 
58 static void stv6110_release(struct dvb_frontend *fe)
59 {
60 	kfree(fe->tuner_priv);
61 	fe->tuner_priv = NULL;
62 }
63 
64 static int stv6110_write_regs(struct dvb_frontend *fe, u8 buf[],
65 							int start, int len)
66 {
67 	struct stv6110_priv *priv = fe->tuner_priv;
68 	int rc;
69 	u8 cmdbuf[MAX_XFER_SIZE];
70 	struct i2c_msg msg = {
71 		.addr	= priv->i2c_address,
72 		.flags	= 0,
73 		.buf	= cmdbuf,
74 		.len	= len + 1
75 	};
76 
77 	dprintk("%s\n", __func__);
78 
79 	if (1 + len > sizeof(cmdbuf)) {
80 		printk(KERN_WARNING
81 		       "%s: i2c wr: len=%d is too big!\n",
82 		       KBUILD_MODNAME, len);
83 		return -EINVAL;
84 	}
85 
86 	if (start + len > 8)
87 		return -EINVAL;
88 
89 	memcpy(&cmdbuf[1], buf, len);
90 	cmdbuf[0] = start;
91 
92 	if (fe->ops.i2c_gate_ctrl)
93 		fe->ops.i2c_gate_ctrl(fe, 1);
94 
95 	rc = i2c_transfer(priv->i2c, &msg, 1);
96 	if (rc != 1)
97 		dprintk("%s: i2c error\n", __func__);
98 
99 	if (fe->ops.i2c_gate_ctrl)
100 		fe->ops.i2c_gate_ctrl(fe, 0);
101 
102 	return 0;
103 }
104 
105 static int stv6110_read_regs(struct dvb_frontend *fe, u8 regs[],
106 							int start, int len)
107 {
108 	struct stv6110_priv *priv = fe->tuner_priv;
109 	int rc;
110 	u8 reg[] = { start };
111 	struct i2c_msg msg[] = {
112 		{
113 			.addr	= priv->i2c_address,
114 			.flags	= 0,
115 			.buf	= reg,
116 			.len	= 1,
117 		}, {
118 			.addr	= priv->i2c_address,
119 			.flags	= I2C_M_RD,
120 			.buf	= regs,
121 			.len	= len,
122 		},
123 	};
124 
125 	if (fe->ops.i2c_gate_ctrl)
126 		fe->ops.i2c_gate_ctrl(fe, 1);
127 
128 	rc = i2c_transfer(priv->i2c, msg, 2);
129 	if (rc != 2)
130 		dprintk("%s: i2c error\n", __func__);
131 
132 	if (fe->ops.i2c_gate_ctrl)
133 		fe->ops.i2c_gate_ctrl(fe, 0);
134 
135 	memcpy(&priv->regs[start], regs, len);
136 
137 	return 0;
138 }
139 
140 static int stv6110_read_reg(struct dvb_frontend *fe, int start)
141 {
142 	u8 buf[] = { 0 };
143 	stv6110_read_regs(fe, buf, start, 1);
144 
145 	return buf[0];
146 }
147 
148 static int stv6110_sleep(struct dvb_frontend *fe)
149 {
150 	u8 reg[] = { 0 };
151 	stv6110_write_regs(fe, reg, 0, 1);
152 
153 	return 0;
154 }
155 
156 static u32 carrier_width(u32 symbol_rate, enum fe_rolloff rolloff)
157 {
158 	u32 rlf;
159 
160 	switch (rolloff) {
161 	case ROLLOFF_20:
162 		rlf = 20;
163 		break;
164 	case ROLLOFF_25:
165 		rlf = 25;
166 		break;
167 	default:
168 		rlf = 35;
169 		break;
170 	}
171 
172 	return symbol_rate  + ((symbol_rate * rlf) / 100);
173 }
174 
175 static int stv6110_set_bandwidth(struct dvb_frontend *fe, u32 bandwidth)
176 {
177 	struct stv6110_priv *priv = fe->tuner_priv;
178 	u8 r8, ret = 0x04;
179 	int i;
180 
181 	if ((bandwidth / 2) > 36000000) /*BW/2 max=31+5=36 mhz for r8=31*/
182 		r8 = 31;
183 	else if ((bandwidth / 2) < 5000000) /* BW/2 min=5Mhz for F=0 */
184 		r8 = 0;
185 	else /*if 5 < BW/2 < 36*/
186 		r8 = (bandwidth / 2) / 1000000 - 5;
187 
188 	/* ctrl3, RCCLKOFF = 0 Activate the calibration Clock */
189 	/* ctrl3, CF = r8 Set the LPF value */
190 	priv->regs[RSTV6110_CTRL3] &= ~((1 << 6) | 0x1f);
191 	priv->regs[RSTV6110_CTRL3] |= (r8 & 0x1f);
192 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL3], RSTV6110_CTRL3, 1);
193 	/* stat1, CALRCSTRT = 1 Start LPF auto calibration*/
194 	priv->regs[RSTV6110_STAT1] |= 0x02;
195 	stv6110_write_regs(fe, &priv->regs[RSTV6110_STAT1], RSTV6110_STAT1, 1);
196 
197 	i = 0;
198 	/* Wait for CALRCSTRT == 0 */
199 	while ((i < 10) && (ret != 0)) {
200 		ret = ((stv6110_read_reg(fe, RSTV6110_STAT1)) & 0x02);
201 		mdelay(1);	/* wait for LPF auto calibration */
202 		i++;
203 	}
204 
205 	/* RCCLKOFF = 1 calibration done, deactivate the calibration Clock */
206 	priv->regs[RSTV6110_CTRL3] |= (1 << 6);
207 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL3], RSTV6110_CTRL3, 1);
208 	return 0;
209 }
210 
211 static int stv6110_init(struct dvb_frontend *fe)
212 {
213 	struct stv6110_priv *priv = fe->tuner_priv;
214 	u8 buf0[] = { 0x07, 0x11, 0xdc, 0x85, 0x17, 0x01, 0xe6, 0x1e };
215 
216 	memcpy(priv->regs, buf0, 8);
217 	/* K = (Reference / 1000000) - 16 */
218 	priv->regs[RSTV6110_CTRL1] &= ~(0x1f << 3);
219 	priv->regs[RSTV6110_CTRL1] |=
220 				((((priv->mclk / 1000000) - 16) & 0x1f) << 3);
221 
222 	/* divisor value for the output clock */
223 	priv->regs[RSTV6110_CTRL2] &= ~0xc0;
224 	priv->regs[RSTV6110_CTRL2] |= (priv->clk_div << 6);
225 
226 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL1], RSTV6110_CTRL1, 8);
227 	msleep(1);
228 	stv6110_set_bandwidth(fe, 72000000);
229 
230 	return 0;
231 }
232 
233 static int stv6110_get_frequency(struct dvb_frontend *fe, u32 *frequency)
234 {
235 	struct stv6110_priv *priv = fe->tuner_priv;
236 	u32 nbsteps, divider, psd2, freq;
237 	u8 regs[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
238 
239 	stv6110_read_regs(fe, regs, 0, 8);
240 	/*N*/
241 	divider = (priv->regs[RSTV6110_TUNING2] & 0x0f) << 8;
242 	divider += priv->regs[RSTV6110_TUNING1];
243 
244 	/*R*/
245 	nbsteps  = (priv->regs[RSTV6110_TUNING2] >> 6) & 3;
246 	/*p*/
247 	psd2  = (priv->regs[RSTV6110_TUNING2] >> 4) & 1;
248 
249 	freq = divider * (priv->mclk / 1000);
250 	freq /= (1 << (nbsteps + psd2));
251 	freq /= 4;
252 
253 	*frequency = freq;
254 
255 	return 0;
256 }
257 
258 static int stv6110_set_frequency(struct dvb_frontend *fe, u32 frequency)
259 {
260 	struct stv6110_priv *priv = fe->tuner_priv;
261 	u8 ret = 0x04;
262 	u32 divider, ref, p, presc, i, result_freq, vco_freq;
263 	s32 p_calc, p_calc_opt = 1000, r_div, r_div_opt = 0, p_val;
264 
265 	dprintk("%s, freq=%d kHz, mclk=%d Hz\n", __func__,
266 						frequency, priv->mclk);
267 
268 	/* K = (Reference / 1000000) - 16 */
269 	priv->regs[RSTV6110_CTRL1] &= ~(0x1f << 3);
270 	priv->regs[RSTV6110_CTRL1] |=
271 				((((priv->mclk / 1000000) - 16) & 0x1f) << 3);
272 
273 	/* BB_GAIN = db/2 */
274 	priv->regs[RSTV6110_CTRL2] &= ~0x0f;
275 	priv->regs[RSTV6110_CTRL2] |= (priv->gain & 0x0f);
276 
277 	if (frequency <= 1023000) {
278 		p = 1;
279 		presc = 0;
280 	} else if (frequency <= 1300000) {
281 		p = 1;
282 		presc = 1;
283 	} else if (frequency <= 2046000) {
284 		p = 0;
285 		presc = 0;
286 	} else {
287 		p = 0;
288 		presc = 1;
289 	}
290 	/* DIV4SEL = p*/
291 	priv->regs[RSTV6110_TUNING2] &= ~(1 << 4);
292 	priv->regs[RSTV6110_TUNING2] |= (p << 4);
293 
294 	/* PRESC32ON = presc */
295 	priv->regs[RSTV6110_TUNING2] &= ~(1 << 5);
296 	priv->regs[RSTV6110_TUNING2] |= (presc << 5);
297 
298 	p_val = (int)(1 << (p + 1)) * 10;/* P = 2 or P = 4 */
299 	for (r_div = 0; r_div <= 3; r_div++) {
300 		p_calc = (priv->mclk / 100000);
301 		p_calc /= (1 << (r_div + 1));
302 		if ((abssub(p_calc, p_val)) < (abssub(p_calc_opt, p_val)))
303 			r_div_opt = r_div;
304 
305 		p_calc_opt = (priv->mclk / 100000);
306 		p_calc_opt /= (1 << (r_div_opt + 1));
307 	}
308 
309 	ref = priv->mclk / ((1 << (r_div_opt + 1))  * (1 << (p + 1)));
310 	divider = (((frequency * 1000) + (ref >> 1)) / ref);
311 
312 	/* RDIV = r_div_opt */
313 	priv->regs[RSTV6110_TUNING2] &= ~(3 << 6);
314 	priv->regs[RSTV6110_TUNING2] |= (((r_div_opt) & 3) << 6);
315 
316 	/* NDIV_MSB = MSB(divider) */
317 	priv->regs[RSTV6110_TUNING2] &= ~0x0f;
318 	priv->regs[RSTV6110_TUNING2] |= (((divider) >> 8) & 0x0f);
319 
320 	/* NDIV_LSB, LSB(divider) */
321 	priv->regs[RSTV6110_TUNING1] = (divider & 0xff);
322 
323 	/* CALVCOSTRT = 1 VCO Auto Calibration */
324 	priv->regs[RSTV6110_STAT1] |= 0x04;
325 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL1],
326 						RSTV6110_CTRL1, 8);
327 
328 	i = 0;
329 	/* Wait for CALVCOSTRT == 0 */
330 	while ((i < 10) && (ret != 0)) {
331 		ret = ((stv6110_read_reg(fe, RSTV6110_STAT1)) & 0x04);
332 		msleep(1); /* wait for VCO auto calibration */
333 		i++;
334 	}
335 
336 	ret = stv6110_read_reg(fe, RSTV6110_STAT1);
337 	stv6110_get_frequency(fe, &result_freq);
338 
339 	vco_freq = divider * ((priv->mclk / 1000) / ((1 << (r_div_opt + 1))));
340 	dprintk("%s, stat1=%x, lo_freq=%d kHz, vco_frec=%d kHz\n", __func__,
341 						ret, result_freq, vco_freq);
342 
343 	return 0;
344 }
345 
346 static int stv6110_set_params(struct dvb_frontend *fe)
347 {
348 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
349 	u32 bandwidth = carrier_width(c->symbol_rate, c->rolloff);
350 
351 	stv6110_set_frequency(fe, c->frequency);
352 	stv6110_set_bandwidth(fe, bandwidth);
353 
354 	return 0;
355 }
356 
357 static int stv6110_get_bandwidth(struct dvb_frontend *fe, u32 *bandwidth)
358 {
359 	struct stv6110_priv *priv = fe->tuner_priv;
360 	u8 r8 = 0;
361 	u8 regs[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
362 	stv6110_read_regs(fe, regs, 0, 8);
363 
364 	/* CF */
365 	r8 = priv->regs[RSTV6110_CTRL3] & 0x1f;
366 	*bandwidth = (r8 + 5) * 2000000;/* x2 for ZIF tuner BW/2 = F+5 Mhz */
367 
368 	return 0;
369 }
370 
371 static const struct dvb_tuner_ops stv6110_tuner_ops = {
372 	.info = {
373 		.name = "ST STV6110",
374 		.frequency_min_hz  =  950 * MHz,
375 		.frequency_max_hz  = 2150 * MHz,
376 		.frequency_step_hz =    1 * MHz,
377 	},
378 	.init = stv6110_init,
379 	.release = stv6110_release,
380 	.sleep = stv6110_sleep,
381 	.set_params = stv6110_set_params,
382 	.get_frequency = stv6110_get_frequency,
383 	.set_frequency = stv6110_set_frequency,
384 	.get_bandwidth = stv6110_get_bandwidth,
385 	.set_bandwidth = stv6110_set_bandwidth,
386 
387 };
388 
389 struct dvb_frontend *stv6110_attach(struct dvb_frontend *fe,
390 					const struct stv6110_config *config,
391 					struct i2c_adapter *i2c)
392 {
393 	struct stv6110_priv *priv = NULL;
394 	u8 reg0[] = { 0x00, 0x07, 0x11, 0xdc, 0x85, 0x17, 0x01, 0xe6, 0x1e };
395 
396 	struct i2c_msg msg[] = {
397 		{
398 			.addr = config->i2c_address,
399 			.flags = 0,
400 			.buf = reg0,
401 			.len = 9
402 		}
403 	};
404 	int ret;
405 
406 	/* divisor value for the output clock */
407 	reg0[2] &= ~0xc0;
408 	reg0[2] |= (config->clk_div << 6);
409 
410 	if (fe->ops.i2c_gate_ctrl)
411 		fe->ops.i2c_gate_ctrl(fe, 1);
412 
413 	ret = i2c_transfer(i2c, msg, 1);
414 
415 	if (fe->ops.i2c_gate_ctrl)
416 		fe->ops.i2c_gate_ctrl(fe, 0);
417 
418 	if (ret != 1)
419 		return NULL;
420 
421 	priv = kzalloc(sizeof(struct stv6110_priv), GFP_KERNEL);
422 	if (priv == NULL)
423 		return NULL;
424 
425 	priv->i2c_address = config->i2c_address;
426 	priv->i2c = i2c;
427 	priv->mclk = config->mclk;
428 	priv->clk_div = config->clk_div;
429 	priv->gain = config->gain;
430 
431 	memcpy(&priv->regs, &reg0[1], 8);
432 
433 	memcpy(&fe->ops.tuner_ops, &stv6110_tuner_ops,
434 				sizeof(struct dvb_tuner_ops));
435 	fe->tuner_priv = priv;
436 	printk(KERN_INFO "STV6110 attached on addr=%x!\n", priv->i2c_address);
437 
438 	return fe;
439 }
440 EXPORT_SYMBOL(stv6110_attach);
441 
442 module_param(debug, int, 0644);
443 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
444 
445 MODULE_DESCRIPTION("ST STV6110 driver");
446 MODULE_AUTHOR("Igor M. Liplianin");
447 MODULE_LICENSE("GPL");
448