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
22static int debug;
23
24struct 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
40static s32 abssub(s32 a, s32 b)
41{
42	if (a > b)
43		return a - b;
44	else
45		return b - a;
46};
47
48static void stv6110_release(struct dvb_frontend *fe)
49{
50	kfree(fe->tuner_priv);
51	fe->tuner_priv = NULL;
52}
53
54static 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
95static 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
130static 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
138static 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
146static 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
165static 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
201static 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
223static 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
248static 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
336static 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
347static 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
361static 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
379struct 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}
430EXPORT_SYMBOL_GPL(stv6110_attach);
431
432module_param(debug, int, 0644);
433MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
434
435MODULE_DESCRIPTION("ST STV6110 driver");
436MODULE_AUTHOR("Igor M. Liplianin");
437MODULE_LICENSE("GPL");
438