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
36static int debug;
37
38struct 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
54static s32 abssub(s32 a, s32 b)
55{
56	if (a > b)
57		return a - b;
58	else
59		return b - a;
60};
61
62static int stv6110_release(struct dvb_frontend *fe)
63{
64	kfree(fe->tuner_priv);
65	fe->tuner_priv = NULL;
66	return 0;
67}
68
69static 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
110static 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
145static 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
153static 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
161static u32 carrier_width(u32 symbol_rate, fe_rolloff_t 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
180static 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
216static 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
238static 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
263static 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
360static 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
371static 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
385static 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
403struct 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}
454EXPORT_SYMBOL(stv6110_attach);
455
456module_param(debug, int, 0644);
457MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
458
459MODULE_DESCRIPTION("ST STV6110 driver");
460MODULE_AUTHOR("Igor M. Liplianin");
461MODULE_LICENSE("GPL");
462