1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 Conexant cx22700 DVB OFDM demodulator driver
4
5 Copyright (C) 2001-2002 Convergence Integrated Media GmbH
6 Holger Waechtler <holger@convergence.de>
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 "cx22700.h"
18
19
20 struct cx22700_state {
21
22 struct i2c_adapter* i2c;
23
24 const struct cx22700_config* config;
25
26 struct dvb_frontend frontend;
27 };
28
29
30 static int debug;
31 #define dprintk(args...) \
32 do { \
33 if (debug) printk(KERN_DEBUG "cx22700: " args); \
34 } while (0)
35
36 static u8 init_tab [] = {
37 0x04, 0x10,
38 0x05, 0x09,
39 0x06, 0x00,
40 0x08, 0x04,
41 0x09, 0x00,
42 0x0a, 0x01,
43 0x15, 0x40,
44 0x16, 0x10,
45 0x17, 0x87,
46 0x18, 0x17,
47 0x1a, 0x10,
48 0x25, 0x04,
49 0x2e, 0x00,
50 0x39, 0x00,
51 0x3a, 0x04,
52 0x45, 0x08,
53 0x46, 0x02,
54 0x47, 0x05,
55 };
56
57
cx22700_writereg(struct cx22700_state * state,u8 reg,u8 data)58 static int cx22700_writereg (struct cx22700_state* state, u8 reg, u8 data)
59 {
60 int ret;
61 u8 buf [] = { reg, data };
62 struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf, .len = 2 };
63
64 dprintk ("%s\n", __func__);
65
66 ret = i2c_transfer (state->i2c, &msg, 1);
67
68 if (ret != 1)
69 printk("%s: writereg error (reg == 0x%02x, val == 0x%02x, ret == %i)\n",
70 __func__, reg, data, ret);
71
72 return (ret != 1) ? -1 : 0;
73 }
74
cx22700_readreg(struct cx22700_state * state,u8 reg)75 static int cx22700_readreg (struct cx22700_state* state, u8 reg)
76 {
77 int ret;
78 u8 b0 [] = { reg };
79 u8 b1 [] = { 0 };
80 struct i2c_msg msg [] = { { .addr = state->config->demod_address, .flags = 0, .buf = b0, .len = 1 },
81 { .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = b1, .len = 1 } };
82
83 dprintk ("%s\n", __func__);
84
85 ret = i2c_transfer (state->i2c, msg, 2);
86
87 if (ret != 2) return -EIO;
88
89 return b1[0];
90 }
91
cx22700_set_inversion(struct cx22700_state * state,int inversion)92 static int cx22700_set_inversion (struct cx22700_state* state, int inversion)
93 {
94 u8 val;
95
96 dprintk ("%s\n", __func__);
97
98 switch (inversion) {
99 case INVERSION_AUTO:
100 return -EOPNOTSUPP;
101 case INVERSION_ON:
102 val = cx22700_readreg (state, 0x09);
103 return cx22700_writereg (state, 0x09, val | 0x01);
104 case INVERSION_OFF:
105 val = cx22700_readreg (state, 0x09);
106 return cx22700_writereg (state, 0x09, val & 0xfe);
107 default:
108 return -EINVAL;
109 }
110 }
111
cx22700_set_tps(struct cx22700_state * state,struct dtv_frontend_properties * p)112 static int cx22700_set_tps(struct cx22700_state *state,
113 struct dtv_frontend_properties *p)
114 {
115 static const u8 qam_tab [4] = { 0, 1, 0, 2 };
116 static const u8 fec_tab [6] = { 0, 1, 2, 0, 3, 4 };
117 u8 val;
118
119 dprintk ("%s\n", __func__);
120
121 if (p->code_rate_HP < FEC_1_2 || p->code_rate_HP > FEC_7_8)
122 return -EINVAL;
123
124 if (p->code_rate_LP < FEC_1_2 || p->code_rate_LP > FEC_7_8)
125 return -EINVAL;
126
127 if (p->code_rate_HP == FEC_4_5 || p->code_rate_LP == FEC_4_5)
128 return -EINVAL;
129
130 if ((int)p->guard_interval < GUARD_INTERVAL_1_32 ||
131 p->guard_interval > GUARD_INTERVAL_1_4)
132 return -EINVAL;
133
134 if (p->transmission_mode != TRANSMISSION_MODE_2K &&
135 p->transmission_mode != TRANSMISSION_MODE_8K)
136 return -EINVAL;
137
138 if (p->modulation != QPSK &&
139 p->modulation != QAM_16 &&
140 p->modulation != QAM_64)
141 return -EINVAL;
142
143 if ((int)p->hierarchy < HIERARCHY_NONE ||
144 p->hierarchy > HIERARCHY_4)
145 return -EINVAL;
146
147 if (p->bandwidth_hz > 8000000 || p->bandwidth_hz < 6000000)
148 return -EINVAL;
149
150 if (p->bandwidth_hz == 7000000)
151 cx22700_writereg (state, 0x09, cx22700_readreg (state, 0x09 | 0x10));
152 else
153 cx22700_writereg (state, 0x09, cx22700_readreg (state, 0x09 & ~0x10));
154
155 val = qam_tab[p->modulation - QPSK];
156 val |= p->hierarchy - HIERARCHY_NONE;
157
158 cx22700_writereg (state, 0x04, val);
159
160 if (p->code_rate_HP - FEC_1_2 >= sizeof(fec_tab) ||
161 p->code_rate_LP - FEC_1_2 >= sizeof(fec_tab))
162 return -EINVAL;
163 val = fec_tab[p->code_rate_HP - FEC_1_2] << 3;
164 val |= fec_tab[p->code_rate_LP - FEC_1_2];
165
166 cx22700_writereg (state, 0x05, val);
167
168 val = (p->guard_interval - GUARD_INTERVAL_1_32) << 2;
169 val |= p->transmission_mode - TRANSMISSION_MODE_2K;
170
171 cx22700_writereg (state, 0x06, val);
172
173 cx22700_writereg (state, 0x08, 0x04 | 0x02); /* use user tps parameters */
174 cx22700_writereg (state, 0x08, 0x04); /* restart acquisition */
175
176 return 0;
177 }
178
cx22700_get_tps(struct cx22700_state * state,struct dtv_frontend_properties * p)179 static int cx22700_get_tps(struct cx22700_state *state,
180 struct dtv_frontend_properties *p)
181 {
182 static const enum fe_modulation qam_tab[3] = { QPSK, QAM_16, QAM_64 };
183 static const enum fe_code_rate fec_tab[5] = {
184 FEC_1_2, FEC_2_3, FEC_3_4, FEC_5_6, FEC_7_8
185 };
186 u8 val;
187
188 dprintk ("%s\n", __func__);
189
190 if (!(cx22700_readreg(state, 0x07) & 0x20)) /* tps valid? */
191 return -EAGAIN;
192
193 val = cx22700_readreg (state, 0x01);
194
195 if ((val & 0x7) > 4)
196 p->hierarchy = HIERARCHY_AUTO;
197 else
198 p->hierarchy = HIERARCHY_NONE + (val & 0x7);
199
200 if (((val >> 3) & 0x3) > 2)
201 p->modulation = QAM_AUTO;
202 else
203 p->modulation = qam_tab[(val >> 3) & 0x3];
204
205 val = cx22700_readreg (state, 0x02);
206
207 if (((val >> 3) & 0x07) > 4)
208 p->code_rate_HP = FEC_AUTO;
209 else
210 p->code_rate_HP = fec_tab[(val >> 3) & 0x07];
211
212 if ((val & 0x07) > 4)
213 p->code_rate_LP = FEC_AUTO;
214 else
215 p->code_rate_LP = fec_tab[val & 0x07];
216
217 val = cx22700_readreg (state, 0x03);
218
219 p->guard_interval = GUARD_INTERVAL_1_32 + ((val >> 6) & 0x3);
220 p->transmission_mode = TRANSMISSION_MODE_2K + ((val >> 5) & 0x1);
221
222 return 0;
223 }
224
cx22700_init(struct dvb_frontend * fe)225 static int cx22700_init (struct dvb_frontend* fe)
226
227 { struct cx22700_state* state = fe->demodulator_priv;
228 int i;
229
230 dprintk("cx22700_init: init chip\n");
231
232 cx22700_writereg (state, 0x00, 0x02); /* soft reset */
233 cx22700_writereg (state, 0x00, 0x00);
234
235 msleep(10);
236
237 for (i=0; i<sizeof(init_tab); i+=2)
238 cx22700_writereg (state, init_tab[i], init_tab[i+1]);
239
240 cx22700_writereg (state, 0x00, 0x01);
241
242 return 0;
243 }
244
cx22700_read_status(struct dvb_frontend * fe,enum fe_status * status)245 static int cx22700_read_status(struct dvb_frontend *fe, enum fe_status *status)
246 {
247 struct cx22700_state* state = fe->demodulator_priv;
248
249 u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
250 | (cx22700_readreg (state, 0x0e) << 1);
251 u8 sync = cx22700_readreg (state, 0x07);
252
253 *status = 0;
254
255 if (rs_ber < 0xff00)
256 *status |= FE_HAS_SIGNAL;
257
258 if (sync & 0x20)
259 *status |= FE_HAS_CARRIER;
260
261 if (sync & 0x10)
262 *status |= FE_HAS_VITERBI;
263
264 if (sync & 0x10)
265 *status |= FE_HAS_SYNC;
266
267 if (*status == 0x0f)
268 *status |= FE_HAS_LOCK;
269
270 return 0;
271 }
272
cx22700_read_ber(struct dvb_frontend * fe,u32 * ber)273 static int cx22700_read_ber(struct dvb_frontend* fe, u32* ber)
274 {
275 struct cx22700_state* state = fe->demodulator_priv;
276
277 *ber = cx22700_readreg (state, 0x0c) & 0x7f;
278 cx22700_writereg (state, 0x0c, 0x00);
279
280 return 0;
281 }
282
cx22700_read_signal_strength(struct dvb_frontend * fe,u16 * signal_strength)283 static int cx22700_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
284 {
285 struct cx22700_state* state = fe->demodulator_priv;
286
287 u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
288 | (cx22700_readreg (state, 0x0e) << 1);
289 *signal_strength = ~rs_ber;
290
291 return 0;
292 }
293
cx22700_read_snr(struct dvb_frontend * fe,u16 * snr)294 static int cx22700_read_snr(struct dvb_frontend* fe, u16* snr)
295 {
296 struct cx22700_state* state = fe->demodulator_priv;
297
298 u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
299 | (cx22700_readreg (state, 0x0e) << 1);
300 *snr = ~rs_ber;
301
302 return 0;
303 }
304
cx22700_read_ucblocks(struct dvb_frontend * fe,u32 * ucblocks)305 static int cx22700_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
306 {
307 struct cx22700_state* state = fe->demodulator_priv;
308
309 *ucblocks = cx22700_readreg (state, 0x0f);
310 cx22700_writereg (state, 0x0f, 0x00);
311
312 return 0;
313 }
314
cx22700_set_frontend(struct dvb_frontend * fe)315 static int cx22700_set_frontend(struct dvb_frontend *fe)
316 {
317 struct dtv_frontend_properties *c = &fe->dtv_property_cache;
318 struct cx22700_state* state = fe->demodulator_priv;
319
320 cx22700_writereg (state, 0x00, 0x02); /* XXX CHECKME: soft reset*/
321 cx22700_writereg (state, 0x00, 0x00);
322
323 if (fe->ops.tuner_ops.set_params) {
324 fe->ops.tuner_ops.set_params(fe);
325 if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
326 }
327
328 cx22700_set_inversion(state, c->inversion);
329 cx22700_set_tps(state, c);
330 cx22700_writereg (state, 0x37, 0x01); /* PAL loop filter off */
331 cx22700_writereg (state, 0x00, 0x01); /* restart acquire */
332
333 return 0;
334 }
335
cx22700_get_frontend(struct dvb_frontend * fe,struct dtv_frontend_properties * c)336 static int cx22700_get_frontend(struct dvb_frontend *fe,
337 struct dtv_frontend_properties *c)
338 {
339 struct cx22700_state* state = fe->demodulator_priv;
340 u8 reg09 = cx22700_readreg (state, 0x09);
341
342 c->inversion = reg09 & 0x1 ? INVERSION_ON : INVERSION_OFF;
343 return cx22700_get_tps(state, c);
344 }
345
cx22700_i2c_gate_ctrl(struct dvb_frontend * fe,int enable)346 static int cx22700_i2c_gate_ctrl(struct dvb_frontend* fe, int enable)
347 {
348 struct cx22700_state* state = fe->demodulator_priv;
349
350 if (enable) {
351 return cx22700_writereg(state, 0x0a, 0x00);
352 } else {
353 return cx22700_writereg(state, 0x0a, 0x01);
354 }
355 }
356
cx22700_get_tune_settings(struct dvb_frontend * fe,struct dvb_frontend_tune_settings * fesettings)357 static int cx22700_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fesettings)
358 {
359 fesettings->min_delay_ms = 150;
360 fesettings->step_size = 166667;
361 fesettings->max_drift = 166667*2;
362 return 0;
363 }
364
cx22700_release(struct dvb_frontend * fe)365 static void cx22700_release(struct dvb_frontend* fe)
366 {
367 struct cx22700_state* state = fe->demodulator_priv;
368 kfree(state);
369 }
370
371 static const struct dvb_frontend_ops cx22700_ops;
372
cx22700_attach(const struct cx22700_config * config,struct i2c_adapter * i2c)373 struct dvb_frontend* cx22700_attach(const struct cx22700_config* config,
374 struct i2c_adapter* i2c)
375 {
376 struct cx22700_state* state = NULL;
377
378 /* allocate memory for the internal state */
379 state = kzalloc(sizeof(struct cx22700_state), GFP_KERNEL);
380 if (state == NULL) 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 (cx22700_readreg(state, 0x07) < 0) goto error;
388
389 /* create dvb_frontend */
390 memcpy(&state->frontend.ops, &cx22700_ops, sizeof(struct dvb_frontend_ops));
391 state->frontend.demodulator_priv = state;
392 return &state->frontend;
393
394 error:
395 kfree(state);
396 return NULL;
397 }
398
399 static const struct dvb_frontend_ops cx22700_ops = {
400 .delsys = { SYS_DVBT },
401 .info = {
402 .name = "Conexant CX22700 DVB-T",
403 .frequency_min_hz = 470 * MHz,
404 .frequency_max_hz = 860 * MHz,
405 .frequency_stepsize_hz = 166667,
406 .caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
407 FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
408 FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 |
409 FE_CAN_RECOVER
410 },
411
412 .release = cx22700_release,
413
414 .init = cx22700_init,
415 .i2c_gate_ctrl = cx22700_i2c_gate_ctrl,
416
417 .set_frontend = cx22700_set_frontend,
418 .get_frontend = cx22700_get_frontend,
419 .get_tune_settings = cx22700_get_tune_settings,
420
421 .read_status = cx22700_read_status,
422 .read_ber = cx22700_read_ber,
423 .read_signal_strength = cx22700_read_signal_strength,
424 .read_snr = cx22700_read_snr,
425 .read_ucblocks = cx22700_read_ucblocks,
426 };
427
428 module_param(debug, int, 0644);
429 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
430
431 MODULE_DESCRIPTION("Conexant CX22700 DVB-T Demodulator driver");
432 MODULE_AUTHOR("Holger Waechtler");
433 MODULE_LICENSE("GPL");
434
435 EXPORT_SYMBOL(cx22700_attach);
436