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
11struct 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 */
20static 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 */
46static 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
75static 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;
148error:
149	dev_dbg(&state->i2c->dev, "%s: failed=%d\n", __func__, ret);
150	return ret;
151}
152
153static 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
163static 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;
194error:
195	dev_dbg(&state->i2c->dev, "%s: failed=%d\n", __func__, ret);
196	return ret;
197}
198
199static 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;
226error:
227	dev_dbg(&state->i2c->dev, "%s: failed=%d\n", __func__, ret);
228	return ret;
229}
230
231static 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;
246error:
247	dev_dbg(&state->i2c->dev, "%s: failed=%d\n", __func__, ret);
248	return ret;
249}
250
251static int ec100_read_snr(struct dvb_frontend *fe, u16 *snr)
252{
253	*snr = 0;
254	return 0;
255}
256
257static int ec100_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
258{
259	*ucblocks = 0;
260	return 0;
261}
262
263static void ec100_release(struct dvb_frontend *fe)
264{
265	struct ec100_state *state = fe->demodulator_priv;
266	kfree(state);
267}
268
269static const struct dvb_frontend_ops ec100_ops;
270
271struct 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;
298error:
299	kfree(state);
300	return NULL;
301}
302EXPORT_SYMBOL_GPL(ec100_attach);
303
304static 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
329MODULE_AUTHOR("Antti Palosaari <crope@iki.fi>");
330MODULE_DESCRIPTION("E3C EC100 DVB-T demodulator driver");
331MODULE_LICENSE("GPL");
332