1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * stv6110.c
4  *
5  * Driver for ST STV6110 satellite tuner IC.
6  *
7  * Copyright (C) 2009 NetUP Inc.
8  * Copyright (C) 2009 Igor M. Liplianin <liplianin@netup.ru>
9  */
10 
11 #include <linux/slab.h>
12 #include <linux/module.h>
13 #include <linux/dvb/frontend.h>
14 
15 #include <linux/types.h>
16 
17 #include "stv6110.h"
18 
19 /* Max transfer size done by I2C transfer functions */
20 #define MAX_XFER_SIZE  64
21 
22 static int debug;
23 
24 struct stv6110_priv {
25 	int i2c_address;
26 	struct i2c_adapter *i2c;
27 
28 	u32 mclk;
29 	u8 clk_div;
30 	u8 gain;
31 	u8 regs[8];
32 };
33 
34 #define dprintk(args...) \
35 	do { \
36 		if (debug) \
37 			printk(KERN_DEBUG args); \
38 	} while (0)
39 
40 static s32 abssub(s32 a, s32 b)
41 {
42 	if (a > b)
43 		return a - b;
44 	else
45 		return b - a;
46 };
47 
48 static void stv6110_release(struct dvb_frontend *fe)
49 {
50 	kfree(fe->tuner_priv);
51 	fe->tuner_priv = NULL;
52 }
53 
54 static int stv6110_write_regs(struct dvb_frontend *fe, u8 buf[],
55 							int start, int len)
56 {
57 	struct stv6110_priv *priv = fe->tuner_priv;
58 	int rc;
59 	u8 cmdbuf[MAX_XFER_SIZE];
60 	struct i2c_msg msg = {
61 		.addr	= priv->i2c_address,
62 		.flags	= 0,
63 		.buf	= cmdbuf,
64 		.len	= len + 1
65 	};
66 
67 	dprintk("%s\n", __func__);
68 
69 	if (1 + len > sizeof(cmdbuf)) {
70 		printk(KERN_WARNING
71 		       "%s: i2c wr: len=%d is too big!\n",
72 		       KBUILD_MODNAME, len);
73 		return -EINVAL;
74 	}
75 
76 	if (start + len > 8)
77 		return -EINVAL;
78 
79 	memcpy(&cmdbuf[1], buf, len);
80 	cmdbuf[0] = start;
81 
82 	if (fe->ops.i2c_gate_ctrl)
83 		fe->ops.i2c_gate_ctrl(fe, 1);
84 
85 	rc = i2c_transfer(priv->i2c, &msg, 1);
86 	if (rc != 1)
87 		dprintk("%s: i2c error\n", __func__);
88 
89 	if (fe->ops.i2c_gate_ctrl)
90 		fe->ops.i2c_gate_ctrl(fe, 0);
91 
92 	return 0;
93 }
94 
95 static int stv6110_read_regs(struct dvb_frontend *fe, u8 regs[],
96 							int start, int len)
97 {
98 	struct stv6110_priv *priv = fe->tuner_priv;
99 	int rc;
100 	u8 reg[] = { start };
101 	struct i2c_msg msg[] = {
102 		{
103 			.addr	= priv->i2c_address,
104 			.flags	= 0,
105 			.buf	= reg,
106 			.len	= 1,
107 		}, {
108 			.addr	= priv->i2c_address,
109 			.flags	= I2C_M_RD,
110 			.buf	= regs,
111 			.len	= len,
112 		},
113 	};
114 
115 	if (fe->ops.i2c_gate_ctrl)
116 		fe->ops.i2c_gate_ctrl(fe, 1);
117 
118 	rc = i2c_transfer(priv->i2c, msg, 2);
119 	if (rc != 2)
120 		dprintk("%s: i2c error\n", __func__);
121 
122 	if (fe->ops.i2c_gate_ctrl)
123 		fe->ops.i2c_gate_ctrl(fe, 0);
124 
125 	memcpy(&priv->regs[start], regs, len);
126 
127 	return 0;
128 }
129 
130 static int stv6110_read_reg(struct dvb_frontend *fe, int start)
131 {
132 	u8 buf[] = { 0 };
133 	stv6110_read_regs(fe, buf, start, 1);
134 
135 	return buf[0];
136 }
137 
138 static int stv6110_sleep(struct dvb_frontend *fe)
139 {
140 	u8 reg[] = { 0 };
141 	stv6110_write_regs(fe, reg, 0, 1);
142 
143 	return 0;
144 }
145 
146 static u32 carrier_width(u32 symbol_rate, enum fe_rolloff rolloff)
147 {
148 	u32 rlf;
149 
150 	switch (rolloff) {
151 	case ROLLOFF_20:
152 		rlf = 20;
153 		break;
154 	case ROLLOFF_25:
155 		rlf = 25;
156 		break;
157 	default:
158 		rlf = 35;
159 		break;
160 	}
161 
162 	return symbol_rate  + ((symbol_rate * rlf) / 100);
163 }
164 
165 static int stv6110_set_bandwidth(struct dvb_frontend *fe, u32 bandwidth)
166 {
167 	struct stv6110_priv *priv = fe->tuner_priv;
168 	u8 r8, ret = 0x04;
169 	int i;
170 
171 	if ((bandwidth / 2) > 36000000) /*BW/2 max=31+5=36 mhz for r8=31*/
172 		r8 = 31;
173 	else if ((bandwidth / 2) < 5000000) /* BW/2 min=5Mhz for F=0 */
174 		r8 = 0;
175 	else /*if 5 < BW/2 < 36*/
176 		r8 = (bandwidth / 2) / 1000000 - 5;
177 
178 	/* ctrl3, RCCLKOFF = 0 Activate the calibration Clock */
179 	/* ctrl3, CF = r8 Set the LPF value */
180 	priv->regs[RSTV6110_CTRL3] &= ~((1 << 6) | 0x1f);
181 	priv->regs[RSTV6110_CTRL3] |= (r8 & 0x1f);
182 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL3], RSTV6110_CTRL3, 1);
183 	/* stat1, CALRCSTRT = 1 Start LPF auto calibration*/
184 	priv->regs[RSTV6110_STAT1] |= 0x02;
185 	stv6110_write_regs(fe, &priv->regs[RSTV6110_STAT1], RSTV6110_STAT1, 1);
186 
187 	i = 0;
188 	/* Wait for CALRCSTRT == 0 */
189 	while ((i < 10) && (ret != 0)) {
190 		ret = ((stv6110_read_reg(fe, RSTV6110_STAT1)) & 0x02);
191 		mdelay(1);	/* wait for LPF auto calibration */
192 		i++;
193 	}
194 
195 	/* RCCLKOFF = 1 calibration done, deactivate the calibration Clock */
196 	priv->regs[RSTV6110_CTRL3] |= (1 << 6);
197 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL3], RSTV6110_CTRL3, 1);
198 	return 0;
199 }
200 
201 static int stv6110_init(struct dvb_frontend *fe)
202 {
203 	struct stv6110_priv *priv = fe->tuner_priv;
204 	u8 buf0[] = { 0x07, 0x11, 0xdc, 0x85, 0x17, 0x01, 0xe6, 0x1e };
205 
206 	memcpy(priv->regs, buf0, 8);
207 	/* K = (Reference / 1000000) - 16 */
208 	priv->regs[RSTV6110_CTRL1] &= ~(0x1f << 3);
209 	priv->regs[RSTV6110_CTRL1] |=
210 				((((priv->mclk / 1000000) - 16) & 0x1f) << 3);
211 
212 	/* divisor value for the output clock */
213 	priv->regs[RSTV6110_CTRL2] &= ~0xc0;
214 	priv->regs[RSTV6110_CTRL2] |= (priv->clk_div << 6);
215 
216 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL1], RSTV6110_CTRL1, 8);
217 	msleep(1);
218 	stv6110_set_bandwidth(fe, 72000000);
219 
220 	return 0;
221 }
222 
223 static int stv6110_get_frequency(struct dvb_frontend *fe, u32 *frequency)
224 {
225 	struct stv6110_priv *priv = fe->tuner_priv;
226 	u32 nbsteps, divider, psd2, freq;
227 	u8 regs[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
228 
229 	stv6110_read_regs(fe, regs, 0, 8);
230 	/*N*/
231 	divider = (priv->regs[RSTV6110_TUNING2] & 0x0f) << 8;
232 	divider += priv->regs[RSTV6110_TUNING1];
233 
234 	/*R*/
235 	nbsteps  = (priv->regs[RSTV6110_TUNING2] >> 6) & 3;
236 	/*p*/
237 	psd2  = (priv->regs[RSTV6110_TUNING2] >> 4) & 1;
238 
239 	freq = divider * (priv->mclk / 1000);
240 	freq /= (1 << (nbsteps + psd2));
241 	freq /= 4;
242 
243 	*frequency = freq;
244 
245 	return 0;
246 }
247 
248 static int stv6110_set_frequency(struct dvb_frontend *fe, u32 frequency)
249 {
250 	struct stv6110_priv *priv = fe->tuner_priv;
251 	u8 ret = 0x04;
252 	u32 divider, ref, p, presc, i, result_freq, vco_freq;
253 	s32 p_calc, p_calc_opt = 1000, r_div, r_div_opt = 0, p_val;
254 
255 	dprintk("%s, freq=%d kHz, mclk=%d Hz\n", __func__,
256 						frequency, priv->mclk);
257 
258 	/* K = (Reference / 1000000) - 16 */
259 	priv->regs[RSTV6110_CTRL1] &= ~(0x1f << 3);
260 	priv->regs[RSTV6110_CTRL1] |=
261 				((((priv->mclk / 1000000) - 16) & 0x1f) << 3);
262 
263 	/* BB_GAIN = db/2 */
264 	priv->regs[RSTV6110_CTRL2] &= ~0x0f;
265 	priv->regs[RSTV6110_CTRL2] |= (priv->gain & 0x0f);
266 
267 	if (frequency <= 1023000) {
268 		p = 1;
269 		presc = 0;
270 	} else if (frequency <= 1300000) {
271 		p = 1;
272 		presc = 1;
273 	} else if (frequency <= 2046000) {
274 		p = 0;
275 		presc = 0;
276 	} else {
277 		p = 0;
278 		presc = 1;
279 	}
280 	/* DIV4SEL = p*/
281 	priv->regs[RSTV6110_TUNING2] &= ~(1 << 4);
282 	priv->regs[RSTV6110_TUNING2] |= (p << 4);
283 
284 	/* PRESC32ON = presc */
285 	priv->regs[RSTV6110_TUNING2] &= ~(1 << 5);
286 	priv->regs[RSTV6110_TUNING2] |= (presc << 5);
287 
288 	p_val = (int)(1 << (p + 1)) * 10;/* P = 2 or P = 4 */
289 	for (r_div = 0; r_div <= 3; r_div++) {
290 		p_calc = (priv->mclk / 100000);
291 		p_calc /= (1 << (r_div + 1));
292 		if ((abssub(p_calc, p_val)) < (abssub(p_calc_opt, p_val)))
293 			r_div_opt = r_div;
294 
295 		p_calc_opt = (priv->mclk / 100000);
296 		p_calc_opt /= (1 << (r_div_opt + 1));
297 	}
298 
299 	ref = priv->mclk / ((1 << (r_div_opt + 1))  * (1 << (p + 1)));
300 	divider = (((frequency * 1000) + (ref >> 1)) / ref);
301 
302 	/* RDIV = r_div_opt */
303 	priv->regs[RSTV6110_TUNING2] &= ~(3 << 6);
304 	priv->regs[RSTV6110_TUNING2] |= (((r_div_opt) & 3) << 6);
305 
306 	/* NDIV_MSB = MSB(divider) */
307 	priv->regs[RSTV6110_TUNING2] &= ~0x0f;
308 	priv->regs[RSTV6110_TUNING2] |= (((divider) >> 8) & 0x0f);
309 
310 	/* NDIV_LSB, LSB(divider) */
311 	priv->regs[RSTV6110_TUNING1] = (divider & 0xff);
312 
313 	/* CALVCOSTRT = 1 VCO Auto Calibration */
314 	priv->regs[RSTV6110_STAT1] |= 0x04;
315 	stv6110_write_regs(fe, &priv->regs[RSTV6110_CTRL1],
316 						RSTV6110_CTRL1, 8);
317 
318 	i = 0;
319 	/* Wait for CALVCOSTRT == 0 */
320 	while ((i < 10) && (ret != 0)) {
321 		ret = ((stv6110_read_reg(fe, RSTV6110_STAT1)) & 0x04);
322 		msleep(1); /* wait for VCO auto calibration */
323 		i++;
324 	}
325 
326 	ret = stv6110_read_reg(fe, RSTV6110_STAT1);
327 	stv6110_get_frequency(fe, &result_freq);
328 
329 	vco_freq = divider * ((priv->mclk / 1000) / ((1 << (r_div_opt + 1))));
330 	dprintk("%s, stat1=%x, lo_freq=%d kHz, vco_frec=%d kHz\n", __func__,
331 						ret, result_freq, vco_freq);
332 
333 	return 0;
334 }
335 
336 static int stv6110_set_params(struct dvb_frontend *fe)
337 {
338 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
339 	u32 bandwidth = carrier_width(c->symbol_rate, c->rolloff);
340 
341 	stv6110_set_frequency(fe, c->frequency);
342 	stv6110_set_bandwidth(fe, bandwidth);
343 
344 	return 0;
345 }
346 
347 static int stv6110_get_bandwidth(struct dvb_frontend *fe, u32 *bandwidth)
348 {
349 	struct stv6110_priv *priv = fe->tuner_priv;
350 	u8 r8 = 0;
351 	u8 regs[] = { 0, 0, 0, 0, 0, 0, 0, 0 };
352 	stv6110_read_regs(fe, regs, 0, 8);
353 
354 	/* CF */
355 	r8 = priv->regs[RSTV6110_CTRL3] & 0x1f;
356 	*bandwidth = (r8 + 5) * 2000000;/* x2 for ZIF tuner BW/2 = F+5 Mhz */
357 
358 	return 0;
359 }
360 
361 static const struct dvb_tuner_ops stv6110_tuner_ops = {
362 	.info = {
363 		.name = "ST STV6110",
364 		.frequency_min_hz  =  950 * MHz,
365 		.frequency_max_hz  = 2150 * MHz,
366 		.frequency_step_hz =    1 * MHz,
367 	},
368 	.init = stv6110_init,
369 	.release = stv6110_release,
370 	.sleep = stv6110_sleep,
371 	.set_params = stv6110_set_params,
372 	.get_frequency = stv6110_get_frequency,
373 	.set_frequency = stv6110_set_frequency,
374 	.get_bandwidth = stv6110_get_bandwidth,
375 	.set_bandwidth = stv6110_set_bandwidth,
376 
377 };
378 
379 struct dvb_frontend *stv6110_attach(struct dvb_frontend *fe,
380 					const struct stv6110_config *config,
381 					struct i2c_adapter *i2c)
382 {
383 	struct stv6110_priv *priv = NULL;
384 	u8 reg0[] = { 0x00, 0x07, 0x11, 0xdc, 0x85, 0x17, 0x01, 0xe6, 0x1e };
385 
386 	struct i2c_msg msg[] = {
387 		{
388 			.addr = config->i2c_address,
389 			.flags = 0,
390 			.buf = reg0,
391 			.len = 9
392 		}
393 	};
394 	int ret;
395 
396 	/* divisor value for the output clock */
397 	reg0[2] &= ~0xc0;
398 	reg0[2] |= (config->clk_div << 6);
399 
400 	if (fe->ops.i2c_gate_ctrl)
401 		fe->ops.i2c_gate_ctrl(fe, 1);
402 
403 	ret = i2c_transfer(i2c, msg, 1);
404 
405 	if (fe->ops.i2c_gate_ctrl)
406 		fe->ops.i2c_gate_ctrl(fe, 0);
407 
408 	if (ret != 1)
409 		return NULL;
410 
411 	priv = kzalloc(sizeof(struct stv6110_priv), GFP_KERNEL);
412 	if (priv == NULL)
413 		return NULL;
414 
415 	priv->i2c_address = config->i2c_address;
416 	priv->i2c = i2c;
417 	priv->mclk = config->mclk;
418 	priv->clk_div = config->clk_div;
419 	priv->gain = config->gain;
420 
421 	memcpy(&priv->regs, &reg0[1], 8);
422 
423 	memcpy(&fe->ops.tuner_ops, &stv6110_tuner_ops,
424 				sizeof(struct dvb_tuner_ops));
425 	fe->tuner_priv = priv;
426 	printk(KERN_INFO "STV6110 attached on addr=%x!\n", priv->i2c_address);
427 
428 	return fe;
429 }
430 EXPORT_SYMBOL_GPL(stv6110_attach);
431 
432 module_param(debug, int, 0644);
433 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
434 
435 MODULE_DESCRIPTION("ST STV6110 driver");
436 MODULE_AUTHOR("Igor M. Liplianin");
437 MODULE_LICENSE("GPL");
438