1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 Legend Silicon LGS-8GL5 DMB-TH OFDM demodulator driver
4
5 Copyright (C) 2008 Sirius International (Hong Kong) Limited
6 Timothy Lee <timothy.lee@siriushk.com>
7
8
9 */
10
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/string.h>
15 #include <linux/slab.h>
16 #include <media/dvb_frontend.h>
17 #include "lgs8gl5.h"
18
19
20 #define REG_RESET 0x02
21 #define REG_RESET_OFF 0x01
22 #define REG_03 0x03
23 #define REG_04 0x04
24 #define REG_07 0x07
25 #define REG_09 0x09
26 #define REG_0A 0x0a
27 #define REG_0B 0x0b
28 #define REG_0C 0x0c
29 #define REG_37 0x37
30 #define REG_STRENGTH 0x4b
31 #define REG_STRENGTH_MASK 0x7f
32 #define REG_STRENGTH_CARRIER 0x80
33 #define REG_INVERSION 0x7c
34 #define REG_INVERSION_ON 0x80
35 #define REG_7D 0x7d
36 #define REG_7E 0x7e
37 #define REG_A2 0xa2
38 #define REG_STATUS 0xa4
39 #define REG_STATUS_SYNC 0x04
40 #define REG_STATUS_LOCK 0x01
41
42
43 struct lgs8gl5_state {
44 struct i2c_adapter *i2c;
45 const struct lgs8gl5_config *config;
46 struct dvb_frontend frontend;
47 };
48
49
50 static int debug;
51 #define dprintk(args...) \
52 do { \
53 if (debug) \
54 printk(KERN_DEBUG "lgs8gl5: " args); \
55 } while (0)
56
57
58 /* Writes into demod's register */
59 static int
lgs8gl5_write_reg(struct lgs8gl5_state * state,u8 reg,u8 data)60 lgs8gl5_write_reg(struct lgs8gl5_state *state, u8 reg, u8 data)
61 {
62 int ret;
63 u8 buf[] = {reg, data};
64 struct i2c_msg msg = {
65 .addr = state->config->demod_address,
66 .flags = 0,
67 .buf = buf,
68 .len = 2
69 };
70
71 ret = i2c_transfer(state->i2c, &msg, 1);
72 if (ret != 1)
73 dprintk("%s: error (reg=0x%02x, val=0x%02x, ret=%i)\n",
74 __func__, reg, data, ret);
75 return (ret != 1) ? -1 : 0;
76 }
77
78
79 /* Reads from demod's register */
80 static int
lgs8gl5_read_reg(struct lgs8gl5_state * state,u8 reg)81 lgs8gl5_read_reg(struct lgs8gl5_state *state, u8 reg)
82 {
83 int ret;
84 u8 b0[] = {reg};
85 u8 b1[] = {0};
86 struct i2c_msg msg[2] = {
87 {
88 .addr = state->config->demod_address,
89 .flags = 0,
90 .buf = b0,
91 .len = 1
92 },
93 {
94 .addr = state->config->demod_address,
95 .flags = I2C_M_RD,
96 .buf = b1,
97 .len = 1
98 }
99 };
100
101 ret = i2c_transfer(state->i2c, msg, 2);
102 if (ret != 2)
103 return -EIO;
104
105 return b1[0];
106 }
107
108
109 static int
lgs8gl5_update_reg(struct lgs8gl5_state * state,u8 reg,u8 data)110 lgs8gl5_update_reg(struct lgs8gl5_state *state, u8 reg, u8 data)
111 {
112 lgs8gl5_read_reg(state, reg);
113 lgs8gl5_write_reg(state, reg, data);
114 return 0;
115 }
116
117
118 /* Writes into alternate device's register */
119 /* TODO: Find out what that device is for! */
120 static int
lgs8gl5_update_alt_reg(struct lgs8gl5_state * state,u8 reg,u8 data)121 lgs8gl5_update_alt_reg(struct lgs8gl5_state *state, u8 reg, u8 data)
122 {
123 int ret;
124 u8 b0[] = {reg};
125 u8 b1[] = {0};
126 u8 b2[] = {reg, data};
127 struct i2c_msg msg[3] = {
128 {
129 .addr = state->config->demod_address + 2,
130 .flags = 0,
131 .buf = b0,
132 .len = 1
133 },
134 {
135 .addr = state->config->demod_address + 2,
136 .flags = I2C_M_RD,
137 .buf = b1,
138 .len = 1
139 },
140 {
141 .addr = state->config->demod_address + 2,
142 .flags = 0,
143 .buf = b2,
144 .len = 2
145 },
146 };
147
148 ret = i2c_transfer(state->i2c, msg, 3);
149 return (ret != 3) ? -1 : 0;
150 }
151
152
153 static void
lgs8gl5_soft_reset(struct lgs8gl5_state * state)154 lgs8gl5_soft_reset(struct lgs8gl5_state *state)
155 {
156 u8 val;
157
158 dprintk("%s\n", __func__);
159
160 val = lgs8gl5_read_reg(state, REG_RESET);
161 lgs8gl5_write_reg(state, REG_RESET, val & ~REG_RESET_OFF);
162 lgs8gl5_write_reg(state, REG_RESET, val | REG_RESET_OFF);
163 msleep(5);
164 }
165
166
167 /* Starts demodulation */
168 static void
lgs8gl5_start_demod(struct lgs8gl5_state * state)169 lgs8gl5_start_demod(struct lgs8gl5_state *state)
170 {
171 u8 val;
172 int n;
173
174 dprintk("%s\n", __func__);
175
176 lgs8gl5_update_alt_reg(state, 0xc2, 0x28);
177 lgs8gl5_soft_reset(state);
178 lgs8gl5_update_reg(state, REG_07, 0x10);
179 lgs8gl5_update_reg(state, REG_07, 0x10);
180 lgs8gl5_write_reg(state, REG_09, 0x0e);
181 lgs8gl5_write_reg(state, REG_0A, 0xe5);
182 lgs8gl5_write_reg(state, REG_0B, 0x35);
183 lgs8gl5_write_reg(state, REG_0C, 0x30);
184
185 lgs8gl5_update_reg(state, REG_03, 0x00);
186 lgs8gl5_update_reg(state, REG_7E, 0x01);
187 lgs8gl5_update_alt_reg(state, 0xc5, 0x00);
188 lgs8gl5_update_reg(state, REG_04, 0x02);
189 lgs8gl5_update_reg(state, REG_37, 0x01);
190 lgs8gl5_soft_reset(state);
191
192 /* Wait for carrier */
193 for (n = 0; n < 10; n++) {
194 val = lgs8gl5_read_reg(state, REG_STRENGTH);
195 dprintk("Wait for carrier[%d] 0x%02X\n", n, val);
196 if (val & REG_STRENGTH_CARRIER)
197 break;
198 msleep(4);
199 }
200 if (!(val & REG_STRENGTH_CARRIER))
201 return;
202
203 /* Wait for lock */
204 for (n = 0; n < 20; n++) {
205 val = lgs8gl5_read_reg(state, REG_STATUS);
206 dprintk("Wait for lock[%d] 0x%02X\n", n, val);
207 if (val & REG_STATUS_LOCK)
208 break;
209 msleep(12);
210 }
211 if (!(val & REG_STATUS_LOCK))
212 return;
213
214 lgs8gl5_write_reg(state, REG_7D, lgs8gl5_read_reg(state, REG_A2));
215 lgs8gl5_soft_reset(state);
216 }
217
218
219 static int
lgs8gl5_init(struct dvb_frontend * fe)220 lgs8gl5_init(struct dvb_frontend *fe)
221 {
222 struct lgs8gl5_state *state = fe->demodulator_priv;
223
224 dprintk("%s\n", __func__);
225
226 lgs8gl5_update_alt_reg(state, 0xc2, 0x28);
227 lgs8gl5_soft_reset(state);
228 lgs8gl5_update_reg(state, REG_07, 0x10);
229 lgs8gl5_update_reg(state, REG_07, 0x10);
230 lgs8gl5_write_reg(state, REG_09, 0x0e);
231 lgs8gl5_write_reg(state, REG_0A, 0xe5);
232 lgs8gl5_write_reg(state, REG_0B, 0x35);
233 lgs8gl5_write_reg(state, REG_0C, 0x30);
234
235 return 0;
236 }
237
238
239 static int
lgs8gl5_read_status(struct dvb_frontend * fe,enum fe_status * status)240 lgs8gl5_read_status(struct dvb_frontend *fe, enum fe_status *status)
241 {
242 struct lgs8gl5_state *state = fe->demodulator_priv;
243 u8 level = lgs8gl5_read_reg(state, REG_STRENGTH);
244 u8 flags = lgs8gl5_read_reg(state, REG_STATUS);
245
246 *status = 0;
247
248 if ((level & REG_STRENGTH_MASK) > 0)
249 *status |= FE_HAS_SIGNAL;
250 if (level & REG_STRENGTH_CARRIER)
251 *status |= FE_HAS_CARRIER;
252 if (flags & REG_STATUS_SYNC)
253 *status |= FE_HAS_SYNC;
254 if (flags & REG_STATUS_LOCK)
255 *status |= FE_HAS_LOCK;
256
257 return 0;
258 }
259
260
261 static int
lgs8gl5_read_ber(struct dvb_frontend * fe,u32 * ber)262 lgs8gl5_read_ber(struct dvb_frontend *fe, u32 *ber)
263 {
264 *ber = 0;
265
266 return 0;
267 }
268
269
270 static int
lgs8gl5_read_signal_strength(struct dvb_frontend * fe,u16 * signal_strength)271 lgs8gl5_read_signal_strength(struct dvb_frontend *fe, u16 *signal_strength)
272 {
273 struct lgs8gl5_state *state = fe->demodulator_priv;
274 u8 level = lgs8gl5_read_reg(state, REG_STRENGTH);
275 *signal_strength = (level & REG_STRENGTH_MASK) << 8;
276
277 return 0;
278 }
279
280
281 static int
lgs8gl5_read_snr(struct dvb_frontend * fe,u16 * snr)282 lgs8gl5_read_snr(struct dvb_frontend *fe, u16 *snr)
283 {
284 struct lgs8gl5_state *state = fe->demodulator_priv;
285 u8 level = lgs8gl5_read_reg(state, REG_STRENGTH);
286 *snr = (level & REG_STRENGTH_MASK) << 8;
287
288 return 0;
289 }
290
291
292 static int
lgs8gl5_read_ucblocks(struct dvb_frontend * fe,u32 * ucblocks)293 lgs8gl5_read_ucblocks(struct dvb_frontend *fe, u32 *ucblocks)
294 {
295 *ucblocks = 0;
296
297 return 0;
298 }
299
300
301 static int
lgs8gl5_set_frontend(struct dvb_frontend * fe)302 lgs8gl5_set_frontend(struct dvb_frontend *fe)
303 {
304 struct dtv_frontend_properties *p = &fe->dtv_property_cache;
305 struct lgs8gl5_state *state = fe->demodulator_priv;
306
307 dprintk("%s\n", __func__);
308
309 if (p->bandwidth_hz != 8000000)
310 return -EINVAL;
311
312 if (fe->ops.tuner_ops.set_params) {
313 fe->ops.tuner_ops.set_params(fe);
314 if (fe->ops.i2c_gate_ctrl)
315 fe->ops.i2c_gate_ctrl(fe, 0);
316 }
317
318 /* lgs8gl5_set_inversion(state, p->inversion); */
319
320 lgs8gl5_start_demod(state);
321
322 return 0;
323 }
324
325
326 static int
lgs8gl5_get_frontend(struct dvb_frontend * fe,struct dtv_frontend_properties * p)327 lgs8gl5_get_frontend(struct dvb_frontend *fe,
328 struct dtv_frontend_properties *p)
329 {
330 struct lgs8gl5_state *state = fe->demodulator_priv;
331
332 u8 inv = lgs8gl5_read_reg(state, REG_INVERSION);
333
334 p->inversion = (inv & REG_INVERSION_ON) ? INVERSION_ON : INVERSION_OFF;
335
336 p->code_rate_HP = FEC_1_2;
337 p->code_rate_LP = FEC_7_8;
338 p->guard_interval = GUARD_INTERVAL_1_32;
339 p->transmission_mode = TRANSMISSION_MODE_2K;
340 p->modulation = QAM_64;
341 p->hierarchy = HIERARCHY_NONE;
342 p->bandwidth_hz = 8000000;
343
344 return 0;
345 }
346
347
348 static int
lgs8gl5_get_tune_settings(struct dvb_frontend * fe,struct dvb_frontend_tune_settings * fesettings)349 lgs8gl5_get_tune_settings(struct dvb_frontend *fe,
350 struct dvb_frontend_tune_settings *fesettings)
351 {
352 fesettings->min_delay_ms = 240;
353 fesettings->step_size = 0;
354 fesettings->max_drift = 0;
355 return 0;
356 }
357
358
359 static void
lgs8gl5_release(struct dvb_frontend * fe)360 lgs8gl5_release(struct dvb_frontend *fe)
361 {
362 struct lgs8gl5_state *state = fe->demodulator_priv;
363 kfree(state);
364 }
365
366
367 static const struct dvb_frontend_ops lgs8gl5_ops;
368
369
370 struct dvb_frontend*
lgs8gl5_attach(const struct lgs8gl5_config * config,struct i2c_adapter * i2c)371 lgs8gl5_attach(const struct lgs8gl5_config *config, struct i2c_adapter *i2c)
372 {
373 struct lgs8gl5_state *state = NULL;
374
375 dprintk("%s\n", __func__);
376
377 /* Allocate memory for the internal state */
378 state = kzalloc(sizeof(struct lgs8gl5_state), GFP_KERNEL);
379 if (state == NULL)
380 goto error;
381
382 /* Setup the state */
383 state->config = config;
384 state->i2c = i2c;
385
386 /* Check if the demod is there */
387 if (lgs8gl5_read_reg(state, REG_RESET) < 0)
388 goto error;
389
390 /* Create dvb_frontend */
391 memcpy(&state->frontend.ops, &lgs8gl5_ops,
392 sizeof(struct dvb_frontend_ops));
393 state->frontend.demodulator_priv = state;
394 return &state->frontend;
395
396 error:
397 kfree(state);
398 return NULL;
399 }
400 EXPORT_SYMBOL(lgs8gl5_attach);
401
402
403 static const struct dvb_frontend_ops lgs8gl5_ops = {
404 .delsys = { SYS_DTMB },
405 .info = {
406 .name = "Legend Silicon LGS-8GL5 DMB-TH",
407 .frequency_min_hz = 474 * MHz,
408 .frequency_max_hz = 858 * MHz,
409 .frequency_stepsize_hz = 10 * kHz,
410 .caps = FE_CAN_FEC_AUTO |
411 FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_32 |
412 FE_CAN_QAM_64 | FE_CAN_QAM_AUTO |
413 FE_CAN_TRANSMISSION_MODE_AUTO |
414 FE_CAN_BANDWIDTH_AUTO |
415 FE_CAN_GUARD_INTERVAL_AUTO |
416 FE_CAN_HIERARCHY_AUTO |
417 FE_CAN_RECOVER
418 },
419
420 .release = lgs8gl5_release,
421
422 .init = lgs8gl5_init,
423
424 .set_frontend = lgs8gl5_set_frontend,
425 .get_frontend = lgs8gl5_get_frontend,
426 .get_tune_settings = lgs8gl5_get_tune_settings,
427
428 .read_status = lgs8gl5_read_status,
429 .read_ber = lgs8gl5_read_ber,
430 .read_signal_strength = lgs8gl5_read_signal_strength,
431 .read_snr = lgs8gl5_read_snr,
432 .read_ucblocks = lgs8gl5_read_ucblocks,
433 };
434
435
436 module_param(debug, int, 0644);
437 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
438
439 MODULE_DESCRIPTION("Legend Silicon LGS-8GL5 DMB-TH Demodulator driver");
440 MODULE_AUTHOR("Timothy Lee");
441 MODULE_LICENSE("GPL");
442