xref: /linux/drivers/media/tuners/e4000.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * Elonics E4000 silicon tuner driver
3  *
4  * Copyright (C) 2012 Antti Palosaari <crope@iki.fi>
5  *
6  *    This program is free software; you can redistribute it and/or modify
7  *    it under the terms of the GNU General Public License as published by
8  *    the Free Software Foundation; either version 2 of the License, or
9  *    (at your option) any later version.
10  *
11  *    This program is distributed in the hope that it will be useful,
12  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *    GNU General Public License for more details.
15  *
16  *    You should have received a copy of the GNU General Public License along
17  *    with this program; if not, write to the Free Software Foundation, Inc.,
18  *    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19  */
20 
21 #include "e4000_priv.h"
22 
23 /* write multiple registers */
24 static int e4000_wr_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len)
25 {
26 	int ret;
27 	u8 buf[1 + len];
28 	struct i2c_msg msg[1] = {
29 		{
30 			.addr = priv->cfg->i2c_addr,
31 			.flags = 0,
32 			.len = sizeof(buf),
33 			.buf = buf,
34 		}
35 	};
36 
37 	buf[0] = reg;
38 	memcpy(&buf[1], val, len);
39 
40 	ret = i2c_transfer(priv->i2c, msg, 1);
41 	if (ret == 1) {
42 		ret = 0;
43 	} else {
44 		dev_warn(&priv->i2c->dev, "%s: i2c wr failed=%d reg=%02x " \
45 				"len=%d\n", KBUILD_MODNAME, ret, reg, len);
46 		ret = -EREMOTEIO;
47 	}
48 	return ret;
49 }
50 
51 /* read multiple registers */
52 static int e4000_rd_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len)
53 {
54 	int ret;
55 	u8 buf[len];
56 	struct i2c_msg msg[2] = {
57 		{
58 			.addr = priv->cfg->i2c_addr,
59 			.flags = 0,
60 			.len = 1,
61 			.buf = &reg,
62 		}, {
63 			.addr = priv->cfg->i2c_addr,
64 			.flags = I2C_M_RD,
65 			.len = sizeof(buf),
66 			.buf = buf,
67 		}
68 	};
69 
70 	ret = i2c_transfer(priv->i2c, msg, 2);
71 	if (ret == 2) {
72 		memcpy(val, buf, len);
73 		ret = 0;
74 	} else {
75 		dev_warn(&priv->i2c->dev, "%s: i2c rd failed=%d reg=%02x " \
76 				"len=%d\n", KBUILD_MODNAME, ret, reg, len);
77 		ret = -EREMOTEIO;
78 	}
79 
80 	return ret;
81 }
82 
83 /* write single register */
84 static int e4000_wr_reg(struct e4000_priv *priv, u8 reg, u8 val)
85 {
86 	return e4000_wr_regs(priv, reg, &val, 1);
87 }
88 
89 /* read single register */
90 static int e4000_rd_reg(struct e4000_priv *priv, u8 reg, u8 *val)
91 {
92 	return e4000_rd_regs(priv, reg, val, 1);
93 }
94 
95 static int e4000_init(struct dvb_frontend *fe)
96 {
97 	struct e4000_priv *priv = fe->tuner_priv;
98 	int ret;
99 
100 	dev_dbg(&priv->i2c->dev, "%s:\n", __func__);
101 
102 	if (fe->ops.i2c_gate_ctrl)
103 		fe->ops.i2c_gate_ctrl(fe, 1);
104 
105 	/* dummy I2C to ensure I2C wakes up */
106 	ret = e4000_wr_reg(priv, 0x02, 0x40);
107 
108 	/* reset */
109 	ret = e4000_wr_reg(priv, 0x00, 0x01);
110 	if (ret < 0)
111 		goto err;
112 
113 	/* disable output clock */
114 	ret = e4000_wr_reg(priv, 0x06, 0x00);
115 	if (ret < 0)
116 		goto err;
117 
118 	ret = e4000_wr_reg(priv, 0x7a, 0x96);
119 	if (ret < 0)
120 		goto err;
121 
122 	/* configure gains */
123 	ret = e4000_wr_regs(priv, 0x7e, "\x01\xfe", 2);
124 	if (ret < 0)
125 		goto err;
126 
127 	ret = e4000_wr_reg(priv, 0x82, 0x00);
128 	if (ret < 0)
129 		goto err;
130 
131 	ret = e4000_wr_reg(priv, 0x24, 0x05);
132 	if (ret < 0)
133 		goto err;
134 
135 	ret = e4000_wr_regs(priv, 0x87, "\x20\x01", 2);
136 	if (ret < 0)
137 		goto err;
138 
139 	ret = e4000_wr_regs(priv, 0x9f, "\x7f\x07", 2);
140 	if (ret < 0)
141 		goto err;
142 
143 	/*
144 	 * TODO: Implement DC offset control correctly.
145 	 * DC offsets has quite much effect for received signal quality in case
146 	 * of direct conversion tuners (Zero-IF). Surely we will now lose few
147 	 * decimals or even decibels from SNR...
148 	 */
149 	/* DC offset control */
150 	ret = e4000_wr_reg(priv, 0x2d, 0x0c);
151 	if (ret < 0)
152 		goto err;
153 
154 	/* gain control */
155 	ret = e4000_wr_reg(priv, 0x1a, 0x17);
156 	if (ret < 0)
157 		goto err;
158 
159 	ret = e4000_wr_reg(priv, 0x1f, 0x1a);
160 	if (ret < 0)
161 		goto err;
162 
163 	if (fe->ops.i2c_gate_ctrl)
164 		fe->ops.i2c_gate_ctrl(fe, 0);
165 
166 	return 0;
167 err:
168 	if (fe->ops.i2c_gate_ctrl)
169 		fe->ops.i2c_gate_ctrl(fe, 0);
170 
171 	dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);
172 	return ret;
173 }
174 
175 static int e4000_sleep(struct dvb_frontend *fe)
176 {
177 	struct e4000_priv *priv = fe->tuner_priv;
178 	int ret;
179 
180 	dev_dbg(&priv->i2c->dev, "%s:\n", __func__);
181 
182 	if (fe->ops.i2c_gate_ctrl)
183 		fe->ops.i2c_gate_ctrl(fe, 1);
184 
185 	ret = e4000_wr_reg(priv, 0x00, 0x00);
186 	if (ret < 0)
187 		goto err;
188 
189 	if (fe->ops.i2c_gate_ctrl)
190 		fe->ops.i2c_gate_ctrl(fe, 0);
191 
192 	return 0;
193 err:
194 	if (fe->ops.i2c_gate_ctrl)
195 		fe->ops.i2c_gate_ctrl(fe, 0);
196 
197 	dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);
198 	return ret;
199 }
200 
201 static int e4000_set_params(struct dvb_frontend *fe)
202 {
203 	struct e4000_priv *priv = fe->tuner_priv;
204 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
205 	int ret, i, sigma_delta;
206 	unsigned int f_VCO;
207 	u8 buf[5];
208 
209 	dev_dbg(&priv->i2c->dev, "%s: delivery_system=%d frequency=%d " \
210 			"bandwidth_hz=%d\n", __func__,
211 			c->delivery_system, c->frequency, c->bandwidth_hz);
212 
213 	if (fe->ops.i2c_gate_ctrl)
214 		fe->ops.i2c_gate_ctrl(fe, 1);
215 
216 	/* gain control manual */
217 	ret = e4000_wr_reg(priv, 0x1a, 0x00);
218 	if (ret < 0)
219 		goto err;
220 
221 	/* PLL */
222 	for (i = 0; i < ARRAY_SIZE(e4000_pll_lut); i++) {
223 		if (c->frequency <= e4000_pll_lut[i].freq)
224 			break;
225 	}
226 
227 	if (i == ARRAY_SIZE(e4000_pll_lut))
228 		goto err;
229 
230 	/*
231 	 * Note: Currently f_VCO overflows when c->frequency is 1 073 741 824 Hz
232 	 * or more.
233 	 */
234 	f_VCO = c->frequency * e4000_pll_lut[i].mul;
235 	sigma_delta = 0x10000UL * (f_VCO % priv->cfg->clock) / priv->cfg->clock;
236 	buf[0] = f_VCO / priv->cfg->clock;
237 	buf[1] = (sigma_delta >> 0) & 0xff;
238 	buf[2] = (sigma_delta >> 8) & 0xff;
239 	buf[3] = 0x00;
240 	buf[4] = e4000_pll_lut[i].div;
241 
242 	dev_dbg(&priv->i2c->dev, "%s: f_VCO=%u pll div=%d sigma_delta=%04x\n",
243 			__func__, f_VCO, buf[0], sigma_delta);
244 
245 	ret = e4000_wr_regs(priv, 0x09, buf, 5);
246 	if (ret < 0)
247 		goto err;
248 
249 	/* LNA filter (RF filter) */
250 	for (i = 0; i < ARRAY_SIZE(e400_lna_filter_lut); i++) {
251 		if (c->frequency <= e400_lna_filter_lut[i].freq)
252 			break;
253 	}
254 
255 	if (i == ARRAY_SIZE(e400_lna_filter_lut))
256 		goto err;
257 
258 	ret = e4000_wr_reg(priv, 0x10, e400_lna_filter_lut[i].val);
259 	if (ret < 0)
260 		goto err;
261 
262 	/* IF filters */
263 	for (i = 0; i < ARRAY_SIZE(e4000_if_filter_lut); i++) {
264 		if (c->bandwidth_hz <= e4000_if_filter_lut[i].freq)
265 			break;
266 	}
267 
268 	if (i == ARRAY_SIZE(e4000_if_filter_lut))
269 		goto err;
270 
271 	buf[0] = e4000_if_filter_lut[i].reg11_val;
272 	buf[1] = e4000_if_filter_lut[i].reg12_val;
273 
274 	ret = e4000_wr_regs(priv, 0x11, buf, 2);
275 	if (ret < 0)
276 		goto err;
277 
278 	/* frequency band */
279 	for (i = 0; i < ARRAY_SIZE(e4000_band_lut); i++) {
280 		if (c->frequency <= e4000_band_lut[i].freq)
281 			break;
282 	}
283 
284 	if (i == ARRAY_SIZE(e4000_band_lut))
285 		goto err;
286 
287 	ret = e4000_wr_reg(priv, 0x07, e4000_band_lut[i].reg07_val);
288 	if (ret < 0)
289 		goto err;
290 
291 	ret = e4000_wr_reg(priv, 0x78, e4000_band_lut[i].reg78_val);
292 	if (ret < 0)
293 		goto err;
294 
295 	/* gain control auto */
296 	ret = e4000_wr_reg(priv, 0x1a, 0x17);
297 	if (ret < 0)
298 		goto err;
299 
300 	if (fe->ops.i2c_gate_ctrl)
301 		fe->ops.i2c_gate_ctrl(fe, 0);
302 
303 	return 0;
304 err:
305 	if (fe->ops.i2c_gate_ctrl)
306 		fe->ops.i2c_gate_ctrl(fe, 0);
307 
308 	dev_dbg(&priv->i2c->dev, "%s: failed=%d\n", __func__, ret);
309 	return ret;
310 }
311 
312 static int e4000_get_if_frequency(struct dvb_frontend *fe, u32 *frequency)
313 {
314 	struct e4000_priv *priv = fe->tuner_priv;
315 
316 	dev_dbg(&priv->i2c->dev, "%s:\n", __func__);
317 
318 	*frequency = 0; /* Zero-IF */
319 
320 	return 0;
321 }
322 
323 static int e4000_release(struct dvb_frontend *fe)
324 {
325 	struct e4000_priv *priv = fe->tuner_priv;
326 
327 	dev_dbg(&priv->i2c->dev, "%s:\n", __func__);
328 
329 	kfree(fe->tuner_priv);
330 
331 	return 0;
332 }
333 
334 static const struct dvb_tuner_ops e4000_tuner_ops = {
335 	.info = {
336 		.name           = "Elonics E4000",
337 		.frequency_min  = 174000000,
338 		.frequency_max  = 862000000,
339 	},
340 
341 	.release = e4000_release,
342 
343 	.init = e4000_init,
344 	.sleep = e4000_sleep,
345 	.set_params = e4000_set_params,
346 
347 	.get_if_frequency = e4000_get_if_frequency,
348 };
349 
350 struct dvb_frontend *e4000_attach(struct dvb_frontend *fe,
351 		struct i2c_adapter *i2c, const struct e4000_config *cfg)
352 {
353 	struct e4000_priv *priv;
354 	int ret;
355 	u8 chip_id;
356 
357 	if (fe->ops.i2c_gate_ctrl)
358 		fe->ops.i2c_gate_ctrl(fe, 1);
359 
360 	priv = kzalloc(sizeof(struct e4000_priv), GFP_KERNEL);
361 	if (!priv) {
362 		ret = -ENOMEM;
363 		dev_err(&i2c->dev, "%s: kzalloc() failed\n", KBUILD_MODNAME);
364 		goto err;
365 	}
366 
367 	priv->cfg = cfg;
368 	priv->i2c = i2c;
369 
370 	/* check if the tuner is there */
371 	ret = e4000_rd_reg(priv, 0x02, &chip_id);
372 	if (ret < 0)
373 		goto err;
374 
375 	dev_dbg(&priv->i2c->dev, "%s: chip_id=%02x\n", __func__, chip_id);
376 
377 	if (chip_id != 0x40)
378 		goto err;
379 
380 	/* put sleep as chip seems to be in normal mode by default */
381 	ret = e4000_wr_reg(priv, 0x00, 0x00);
382 	if (ret < 0)
383 		goto err;
384 
385 	dev_info(&priv->i2c->dev,
386 			"%s: Elonics E4000 successfully identified\n",
387 			KBUILD_MODNAME);
388 
389 	fe->tuner_priv = priv;
390 	memcpy(&fe->ops.tuner_ops, &e4000_tuner_ops,
391 			sizeof(struct dvb_tuner_ops));
392 
393 	if (fe->ops.i2c_gate_ctrl)
394 		fe->ops.i2c_gate_ctrl(fe, 0);
395 
396 	return fe;
397 err:
398 	if (fe->ops.i2c_gate_ctrl)
399 		fe->ops.i2c_gate_ctrl(fe, 0);
400 
401 	dev_dbg(&i2c->dev, "%s: failed=%d\n", __func__, ret);
402 	kfree(priv);
403 	return NULL;
404 }
405 EXPORT_SYMBOL(e4000_attach);
406 
407 MODULE_DESCRIPTION("Elonics E4000 silicon tuner driver");
408 MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
409 MODULE_LICENSE("GPL");
410