1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * E3C EC100 demodulator driver
4  *
5  * Copyright (C) 2009 Antti Palosaari <crope@iki.fi>
6  */
7 
8 #include <media/dvb_frontend.h>
9 #include "ec100.h"
10 
11 struct ec100_state {
12 	struct i2c_adapter *i2c;
13 	struct dvb_frontend frontend;
14 	struct ec100_config config;
15 
16 	u16 ber;
17 };
18 
19 /* write single register */
20 static int ec100_write_reg(struct ec100_state *state, u8 reg, u8 val)
21 {
22 	int ret;
23 	u8 buf[2] = {reg, val};
24 	struct i2c_msg msg[1] = {
25 		{
26 			.addr = state->config.demod_address,
27 			.flags = 0,
28 			.len = sizeof(buf),
29 			.buf = buf,
30 		}
31 	};
32 
33 	ret = i2c_transfer(state->i2c, msg, 1);
34 	if (ret == 1) {
35 		ret = 0;
36 	} else {
37 		dev_warn(&state->i2c->dev, "%s: i2c wr failed=%d reg=%02x\n",
38 				KBUILD_MODNAME, ret, reg);
39 		ret = -EREMOTEIO;
40 	}
41 
42 	return ret;
43 }
44 
45 /* read single register */
46 static int ec100_read_reg(struct ec100_state *state, u8 reg, u8 *val)
47 {
48 	int ret;
49 	struct i2c_msg msg[2] = {
50 		{
51 			.addr = state->config.demod_address,
52 			.flags = 0,
53 			.len = 1,
54 			.buf = &reg
55 		}, {
56 			.addr = state->config.demod_address,
57 			.flags = I2C_M_RD,
58 			.len = 1,
59 			.buf = val
60 		}
61 	};
62 
63 	ret = i2c_transfer(state->i2c, msg, 2);
64 	if (ret == 2) {
65 		ret = 0;
66 	} else {
67 		dev_warn(&state->i2c->dev, "%s: i2c rd failed=%d reg=%02x\n",
68 				KBUILD_MODNAME, ret, reg);
69 		ret = -EREMOTEIO;
70 	}
71 
72 	return ret;
73 }
74 
75 static int ec100_set_frontend(struct dvb_frontend *fe)
76 {
77 	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
78 	struct ec100_state *state = fe->demodulator_priv;
79 	int ret;
80 	u8 tmp, tmp2;
81 
82 	dev_dbg(&state->i2c->dev, "%s: frequency=%d bandwidth_hz=%d\n",
83 			__func__, c->frequency, c->bandwidth_hz);
84 
85 	/* program tuner */
86 	if (fe->ops.tuner_ops.set_params)
87 		fe->ops.tuner_ops.set_params(fe);
88 
89 	ret = ec100_write_reg(state, 0x04, 0x06);
90 	if (ret)
91 		goto error;
92 	ret = ec100_write_reg(state, 0x67, 0x58);
93 	if (ret)
94 		goto error;
95 	ret = ec100_write_reg(state, 0x05, 0x18);
96 	if (ret)
97 		goto error;
98 
99 	/* reg/bw |   6  |   7  |   8
100 	   -------+------+------+------
101 	   A 0x1b | 0xa1 | 0xe7 | 0x2c
102 	   A 0x1c | 0x55 | 0x63 | 0x72
103 	   -------+------+------+------
104 	   B 0x1b | 0xb7 | 0x00 | 0x49
105 	   B 0x1c | 0x55 | 0x64 | 0x72 */
106 
107 	switch (c->bandwidth_hz) {
108 	case 6000000:
109 		tmp = 0xb7;
110 		tmp2 = 0x55;
111 		break;
112 	case 7000000:
113 		tmp = 0x00;
114 		tmp2 = 0x64;
115 		break;
116 	case 8000000:
117 	default:
118 		tmp = 0x49;
119 		tmp2 = 0x72;
120 	}
121 
122 	ret = ec100_write_reg(state, 0x1b, tmp);
123 	if (ret)
124 		goto error;
125 	ret = ec100_write_reg(state, 0x1c, tmp2);
126 	if (ret)
127 		goto error;
128 
129 	ret = ec100_write_reg(state, 0x0c, 0xbb); /* if freq */
130 	if (ret)
131 		goto error;
132 	ret = ec100_write_reg(state, 0x0d, 0x31); /* if freq */
133 	if (ret)
134 		goto error;
135 
136 	ret = ec100_write_reg(state, 0x08, 0x24);
137 	if (ret)
138 		goto error;
139 
140 	ret = ec100_write_reg(state, 0x00, 0x00); /* go */
141 	if (ret)
142 		goto error;
143 	ret = ec100_write_reg(state, 0x00, 0x20); /* go */
144 	if (ret)
145 		goto error;
146 
147 	return ret;
148 error:
149 	dev_dbg(&state->i2c->dev, "%s: failed=%d\n", __func__, ret);
150 	return ret;
151 }
152 
153 static int ec100_get_tune_settings(struct dvb_frontend *fe,
154 	struct dvb_frontend_tune_settings *fesettings)
155 {
156 	fesettings->min_delay_ms = 300;
157 	fesettings->step_size = 0;
158 	fesettings->max_drift = 0;
159 
160 	return 0;
161 }
162 
163 static int ec100_read_status(struct dvb_frontend *fe, enum fe_status *status)
164 {
165 	struct ec100_state *state = fe->demodulator_priv;
166 	int ret;
167 	u8 tmp;
168 	*status = 0;
169 
170 	ret = ec100_read_reg(state, 0x42, &tmp);
171 	if (ret)
172 		goto error;
173 
174 	if (tmp & 0x80) {
175 		/* bit7 set - have lock */
176 		*status |= FE_HAS_SIGNAL | FE_HAS_CARRIER | FE_HAS_VITERBI |
177 			FE_HAS_SYNC | FE_HAS_LOCK;
178 	} else {
179 		ret = ec100_read_reg(state, 0x01, &tmp);
180 		if (ret)
181 			goto error;
182 
183 		if (tmp & 0x10) {
184 			/* bit4 set - have signal */
185 			*status |= FE_HAS_SIGNAL;
186 			if (!(tmp & 0x01)) {
187 				/* bit0 clear - have ~valid signal */
188 				*status |= FE_HAS_CARRIER |  FE_HAS_VITERBI;
189 			}
190 		}
191 	}
192 
193 	return ret;
194 error:
195 	dev_dbg(&state->i2c->dev, "%s: failed=%d\n", __func__, ret);
196 	return ret;
197 }
198 
199 static int ec100_read_ber(struct dvb_frontend *fe, u32 *ber)
200 {
201 	struct ec100_state *state = fe->demodulator_priv;
202 	int ret;
203 	u8 tmp, tmp2;
204 	u16 ber2;
205 
206 	*ber = 0;
207 
208 	ret = ec100_read_reg(state, 0x65, &tmp);
209 	if (ret)
210 		goto error;
211 	ret = ec100_read_reg(state, 0x66, &tmp2);
212 	if (ret)
213 		goto error;
214 
215 	ber2 = (tmp2 << 8) | tmp;
216 
217 	/* if counter overflow or clear */
218 	if (ber2 < state->ber)
219 		*ber = ber2;
220 	else
221 		*ber = ber2 - state->ber;
222 
223 	state->ber = ber2;
224 
225 	return ret;
226 error:
227 	dev_dbg(&state->i2c->dev, "%s: failed=%d\n", __func__, ret);
228 	return ret;
229 }
230 
231 static int ec100_read_signal_strength(struct dvb_frontend *fe, u16 *strength)
232 {
233 	struct ec100_state *state = fe->demodulator_priv;
234 	int ret;
235 	u8 tmp;
236 
237 	ret = ec100_read_reg(state, 0x24, &tmp);
238 	if (ret) {
239 		*strength = 0;
240 		goto error;
241 	}
242 
243 	*strength = ((tmp << 8) | tmp);
244 
245 	return ret;
246 error:
247 	dev_dbg(&state->i2c->dev, "%s: failed=%d\n", __func__, ret);
248 	return ret;
249 }
250 
251 static int ec100_read_snr(struct dvb_frontend *fe, u16 *snr)
252 {
253 	*snr = 0;
254 	return 0;
255 }
256 
257 static int ec100_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
258 {
259 	*ucblocks = 0;
260 	return 0;
261 }
262 
263 static void ec100_release(struct dvb_frontend *fe)
264 {
265 	struct ec100_state *state = fe->demodulator_priv;
266 	kfree(state);
267 }
268 
269 static const struct dvb_frontend_ops ec100_ops;
270 
271 struct dvb_frontend *ec100_attach(const struct ec100_config *config,
272 	struct i2c_adapter *i2c)
273 {
274 	int ret;
275 	struct ec100_state *state = NULL;
276 	u8 tmp;
277 
278 	/* allocate memory for the internal state */
279 	state = kzalloc(sizeof(struct ec100_state), GFP_KERNEL);
280 	if (state == NULL)
281 		goto error;
282 
283 	/* setup the state */
284 	state->i2c = i2c;
285 	memcpy(&state->config, config, sizeof(struct ec100_config));
286 
287 	/* check if the demod is there */
288 	ret = ec100_read_reg(state, 0x33, &tmp);
289 	if (ret || tmp != 0x0b)
290 		goto error;
291 
292 	/* create dvb_frontend */
293 	memcpy(&state->frontend.ops, &ec100_ops,
294 		sizeof(struct dvb_frontend_ops));
295 	state->frontend.demodulator_priv = state;
296 
297 	return &state->frontend;
298 error:
299 	kfree(state);
300 	return NULL;
301 }
302 EXPORT_SYMBOL(ec100_attach);
303 
304 static const struct dvb_frontend_ops ec100_ops = {
305 	.delsys = { SYS_DVBT },
306 	.info = {
307 		.name = "E3C EC100 DVB-T",
308 		.caps =
309 			FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
310 			FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
311 			FE_CAN_QPSK | FE_CAN_QAM_16 |
312 			FE_CAN_QAM_64 | FE_CAN_QAM_AUTO |
313 			FE_CAN_TRANSMISSION_MODE_AUTO |
314 			FE_CAN_GUARD_INTERVAL_AUTO |
315 			FE_CAN_HIERARCHY_AUTO |
316 			FE_CAN_MUTE_TS
317 	},
318 
319 	.release = ec100_release,
320 	.set_frontend = ec100_set_frontend,
321 	.get_tune_settings = ec100_get_tune_settings,
322 	.read_status = ec100_read_status,
323 	.read_ber = ec100_read_ber,
324 	.read_signal_strength = ec100_read_signal_strength,
325 	.read_snr = ec100_read_snr,
326 	.read_ucblocks = ec100_read_ucblocks,
327 };
328 
329 MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
330 MODULE_DESCRIPTION("E3C EC100 DVB-T demodulator driver");
331 MODULE_LICENSE("GPL");
332