summaryrefslogtreecommitdiff
path: root/drivers/media/dvb-frontends/cx22700.c
blob: 86563260d0f2f76eb9e9cf193194bc5adb88ed4f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
/*
    Conexant cx22700 DVB OFDM demodulator driver

    Copyright (C) 2001-2002 Convergence Integrated Media GmbH
	Holger Waechtler <holger@convergence.de>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

*/

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/slab.h>
#include "dvb_frontend.h"
#include "cx22700.h"


struct cx22700_state {

	struct i2c_adapter* i2c;

	const struct cx22700_config* config;

	struct dvb_frontend frontend;
};


static int debug;
#define dprintk(args...) \
	do { \
		if (debug) printk(KERN_DEBUG "cx22700: " args); \
	} while (0)

static u8 init_tab [] = {
	0x04, 0x10,
	0x05, 0x09,
	0x06, 0x00,
	0x08, 0x04,
	0x09, 0x00,
	0x0a, 0x01,
	0x15, 0x40,
	0x16, 0x10,
	0x17, 0x87,
	0x18, 0x17,
	0x1a, 0x10,
	0x25, 0x04,
	0x2e, 0x00,
	0x39, 0x00,
	0x3a, 0x04,
	0x45, 0x08,
	0x46, 0x02,
	0x47, 0x05,
};


static int cx22700_writereg (struct cx22700_state* state, u8 reg, u8 data)
{
	int ret;
	u8 buf [] = { reg, data };
	struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf, .len = 2 };

	dprintk ("%s\n", __func__);

	ret = i2c_transfer (state->i2c, &msg, 1);

	if (ret != 1)
		printk("%s: writereg error (reg == 0x%02x, val == 0x%02x, ret == %i)\n",
			__func__, reg, data, ret);

	return (ret != 1) ? -1 : 0;
}

static int cx22700_readreg (struct cx22700_state* state, u8 reg)
{
	int ret;
	u8 b0 [] = { reg };
	u8 b1 [] = { 0 };
	struct i2c_msg msg [] = { { .addr = state->config->demod_address, .flags = 0, .buf = b0, .len = 1 },
			   { .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = b1, .len = 1 } };

	dprintk ("%s\n", __func__);

	ret = i2c_transfer (state->i2c, msg, 2);

	if (ret != 2) return -EIO;

	return b1[0];
}

static int cx22700_set_inversion (struct cx22700_state* state, int inversion)
{
	u8 val;

	dprintk ("%s\n", __func__);

	switch (inversion) {
	case INVERSION_AUTO:
		return -EOPNOTSUPP;
	case INVERSION_ON:
		val = cx22700_readreg (state, 0x09);
		return cx22700_writereg (state, 0x09, val | 0x01);
	case INVERSION_OFF:
		val = cx22700_readreg (state, 0x09);
		return cx22700_writereg (state, 0x09, val & 0xfe);
	default:
		return -EINVAL;
	}
}

static int cx22700_set_tps(struct cx22700_state *state,
			   struct dtv_frontend_properties *p)
{
	static const u8 qam_tab [4] = { 0, 1, 0, 2 };
	static const u8 fec_tab [6] = { 0, 1, 2, 0, 3, 4 };
	u8 val;

	dprintk ("%s\n", __func__);

	if (p->code_rate_HP < FEC_1_2 || p->code_rate_HP > FEC_7_8)
		return -EINVAL;

	if (p->code_rate_LP < FEC_1_2 || p->code_rate_LP > FEC_7_8)
		return -EINVAL;

	if (p->code_rate_HP == FEC_4_5 || p->code_rate_LP == FEC_4_5)
		return -EINVAL;

	if ((int)p->guard_interval < GUARD_INTERVAL_1_32 ||
	    p->guard_interval > GUARD_INTERVAL_1_4)
		return -EINVAL;

	if (p->transmission_mode != TRANSMISSION_MODE_2K &&
	    p->transmission_mode != TRANSMISSION_MODE_8K)
		return -EINVAL;

	if (p->modulation != QPSK &&
	    p->modulation != QAM_16 &&
	    p->modulation != QAM_64)
		return -EINVAL;

	if ((int)p->hierarchy < HIERARCHY_NONE ||
	    p->hierarchy > HIERARCHY_4)
		return -EINVAL;

	if (p->bandwidth_hz > 8000000 || p->bandwidth_hz < 6000000)
		return -EINVAL;

	if (p->bandwidth_hz == 7000000)
		cx22700_writereg (state, 0x09, cx22700_readreg (state, 0x09 | 0x10));
	else
		cx22700_writereg (state, 0x09, cx22700_readreg (state, 0x09 & ~0x10));

	val = qam_tab[p->modulation - QPSK];
	val |= p->hierarchy - HIERARCHY_NONE;

	cx22700_writereg (state, 0x04, val);

	if (p->code_rate_HP - FEC_1_2 >= sizeof(fec_tab) ||
	    p->code_rate_LP - FEC_1_2 >= sizeof(fec_tab))
		return -EINVAL;
	val = fec_tab[p->code_rate_HP - FEC_1_2] << 3;
	val |= fec_tab[p->code_rate_LP - FEC_1_2];

	cx22700_writereg (state, 0x05, val);

	val = (p->guard_interval - GUARD_INTERVAL_1_32) << 2;
	val |= p->transmission_mode - TRANSMISSION_MODE_2K;

	cx22700_writereg (state, 0x06, val);

	cx22700_writereg (state, 0x08, 0x04 | 0x02);  /* use user tps parameters */
	cx22700_writereg (state, 0x08, 0x04);         /* restart acquisition */

	return 0;
}

static int cx22700_get_tps(struct cx22700_state *state,
			   struct dtv_frontend_properties *p)
{
	static const fe_modulation_t qam_tab [3] = { QPSK, QAM_16, QAM_64 };
	static const fe_code_rate_t fec_tab [5] = { FEC_1_2, FEC_2_3, FEC_3_4,
						    FEC_5_6, FEC_7_8 };
	u8 val;

	dprintk ("%s\n", __func__);

	if (!(cx22700_readreg(state, 0x07) & 0x20))  /*  tps valid? */
		return -EAGAIN;

	val = cx22700_readreg (state, 0x01);

	if ((val & 0x7) > 4)
		p->hierarchy = HIERARCHY_AUTO;
	else
		p->hierarchy = HIERARCHY_NONE + (val & 0x7);

	if (((val >> 3) & 0x3) > 2)
		p->modulation = QAM_AUTO;
	else
		p->modulation = qam_tab[(val >> 3) & 0x3];

	val = cx22700_readreg (state, 0x02);

	if (((val >> 3) & 0x07) > 4)
		p->code_rate_HP = FEC_AUTO;
	else
		p->code_rate_HP = fec_tab[(val >> 3) & 0x07];

	if ((val & 0x07) > 4)
		p->code_rate_LP = FEC_AUTO;
	else
		p->code_rate_LP = fec_tab[val & 0x07];

	val = cx22700_readreg (state, 0x03);

	p->guard_interval = GUARD_INTERVAL_1_32 + ((val >> 6) & 0x3);
	p->transmission_mode = TRANSMISSION_MODE_2K + ((val >> 5) & 0x1);

	return 0;
}

static int cx22700_init (struct dvb_frontend* fe)

{	struct cx22700_state* state = fe->demodulator_priv;
	int i;

	dprintk("cx22700_init: init chip\n");

	cx22700_writereg (state, 0x00, 0x02);   /*  soft reset */
	cx22700_writereg (state, 0x00, 0x00);

	msleep(10);

	for (i=0; i<sizeof(init_tab); i+=2)
		cx22700_writereg (state, init_tab[i], init_tab[i+1]);

	cx22700_writereg (state, 0x00, 0x01);

	return 0;
}

static int cx22700_read_status(struct dvb_frontend* fe, fe_status_t* status)
{
	struct cx22700_state* state = fe->demodulator_priv;

	u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
		   | (cx22700_readreg (state, 0x0e) << 1);
	u8 sync = cx22700_readreg (state, 0x07);

	*status = 0;

	if (rs_ber < 0xff00)
		*status |= FE_HAS_SIGNAL;

	if (sync & 0x20)
		*status |= FE_HAS_CARRIER;

	if (sync & 0x10)
		*status |= FE_HAS_VITERBI;

	if (sync & 0x10)
		*status |= FE_HAS_SYNC;

	if (*status == 0x0f)
		*status |= FE_HAS_LOCK;

	return 0;
}

static int cx22700_read_ber(struct dvb_frontend* fe, u32* ber)
{
	struct cx22700_state* state = fe->demodulator_priv;

	*ber = cx22700_readreg (state, 0x0c) & 0x7f;
	cx22700_writereg (state, 0x0c, 0x00);

	return 0;
}

static int cx22700_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
{
	struct cx22700_state* state = fe->demodulator_priv;

	u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
		   | (cx22700_readreg (state, 0x0e) << 1);
	*signal_strength = ~rs_ber;

	return 0;
}

static int cx22700_read_snr(struct dvb_frontend* fe, u16* snr)
{
	struct cx22700_state* state = fe->demodulator_priv;

	u16 rs_ber = (cx22700_readreg (state, 0x0d) << 9)
		   | (cx22700_readreg (state, 0x0e) << 1);
	*snr = ~rs_ber;

	return 0;
}

static int cx22700_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
{
	struct cx22700_state* state = fe->demodulator_priv;

	*ucblocks = cx22700_readreg (state, 0x0f);
	cx22700_writereg (state, 0x0f, 0x00);

	return 0;
}

static int cx22700_set_frontend(struct dvb_frontend *fe)
{
	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
	struct cx22700_state* state = fe->demodulator_priv;

	cx22700_writereg (state, 0x00, 0x02); /* XXX CHECKME: soft reset*/
	cx22700_writereg (state, 0x00, 0x00);

	if (fe->ops.tuner_ops.set_params) {
		fe->ops.tuner_ops.set_params(fe);
		if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
	}

	cx22700_set_inversion(state, c->inversion);
	cx22700_set_tps(state, c);
	cx22700_writereg (state, 0x37, 0x01);  /* PAL loop filter off */
	cx22700_writereg (state, 0x00, 0x01);  /* restart acquire */

	return 0;
}

static int cx22700_get_frontend(struct dvb_frontend *fe)
{
	struct dtv_frontend_properties *c = &fe->dtv_property_cache;
	struct cx22700_state* state = fe->demodulator_priv;
	u8 reg09 = cx22700_readreg (state, 0x09);

	c->inversion = reg09 & 0x1 ? INVERSION_ON : INVERSION_OFF;
	return cx22700_get_tps(state, c);
}

static int cx22700_i2c_gate_ctrl(struct dvb_frontend* fe, int enable)
{
	struct cx22700_state* state = fe->demodulator_priv;

	if (enable) {
		return cx22700_writereg(state, 0x0a, 0x00);
	} else {
		return cx22700_writereg(state, 0x0a, 0x01);
	}
}

static int cx22700_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fesettings)
{
	fesettings->min_delay_ms = 150;
	fesettings->step_size = 166667;
	fesettings->max_drift = 166667*2;
	return 0;
}

static void cx22700_release(struct dvb_frontend* fe)
{
	struct cx22700_state* state = fe->demodulator_priv;
	kfree(state);
}

static struct dvb_frontend_ops cx22700_ops;

struct dvb_frontend* cx22700_attach(const struct cx22700_config* config,
				    struct i2c_adapter* i2c)
{
	struct cx22700_state* state = NULL;

	/* allocate memory for the internal state */
	state = kzalloc(sizeof(struct cx22700_state), GFP_KERNEL);
	if (state == NULL) goto error;

	/* setup the state */
	state->config = config;
	state->i2c = i2c;

	/* check if the demod is there */
	if (cx22700_readreg(state, 0x07) < 0) goto error;

	/* create dvb_frontend */
	memcpy(&state->frontend.ops, &cx22700_ops, sizeof(struct dvb_frontend_ops));
	state->frontend.demodulator_priv = state;
	return &state->frontend;

error:
	kfree(state);
	return NULL;
}

static struct dvb_frontend_ops cx22700_ops = {
	.delsys = { SYS_DVBT },
	.info = {
		.name			= "Conexant CX22700 DVB-T",
		.frequency_min		= 470000000,
		.frequency_max		= 860000000,
		.frequency_stepsize	= 166667,
		.caps = FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
		      FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
		      FE_CAN_QPSK | FE_CAN_QAM_16 | FE_CAN_QAM_64 |
		      FE_CAN_RECOVER
	},

	.release = cx22700_release,

	.init = cx22700_init,
	.i2c_gate_ctrl = cx22700_i2c_gate_ctrl,

	.set_frontend = cx22700_set_frontend,
	.get_frontend = cx22700_get_frontend,
	.get_tune_settings = cx22700_get_tune_settings,

	.read_status = cx22700_read_status,
	.read_ber = cx22700_read_ber,
	.read_signal_strength = cx22700_read_signal_strength,
	.read_snr = cx22700_read_snr,
	.read_ucblocks = cx22700_read_ucblocks,
};

module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");

MODULE_DESCRIPTION("Conexant CX22700 DVB-T Demodulator driver");
MODULE_AUTHOR("Holger Waechtler");
MODULE_LICENSE("GPL");

EXPORT_SYMBOL(cx22700_attach);