1 /*
2     cx24110 - Single Chip Satellite Channel Receiver driver module
3 
4     Copyright (C) 2002 Peter Hettkamp <peter.hettkamp@htp-tel.de> based on
5     work
6     Copyright (C) 1999 Convergence Integrated Media GmbH <ralph@convergence.de>
7 
8     This program is free software; you can redistribute it and/or modify
9     it under the terms of the GNU General Public License as published by
10     the Free Software Foundation; either version 2 of the License, or
11     (at your option) any later version.
12 
13     This program is distributed in the hope that it will be useful,
14     but WITHOUT ANY WARRANTY; without even the implied warranty of
15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 
17     GNU General Public License for more details.
18 
19     You should have received a copy of the GNU General Public License
20     along with this program; if not, write to the Free Software
21     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 
23 */
24 
25 #include <linux/slab.h>
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/init.h>
29 
30 #include <media/dvb_frontend.h>
31 #include "cx24110.h"
32 
33 
34 struct cx24110_state {
35 
36 	struct i2c_adapter* i2c;
37 
38 	const struct cx24110_config* config;
39 
40 	struct dvb_frontend frontend;
41 
42 	u32 lastber;
43 	u32 lastbler;
44 	u32 lastesn0;
45 };
46 
47 static int debug;
48 #define dprintk(args...) \
49 	do { \
50 		if (debug) printk(KERN_DEBUG "cx24110: " args); \
51 	} while (0)
52 
53 static struct {u8 reg; u8 data;} cx24110_regdata[]=
54 		      /* Comments beginning with @ denote this value should
55 			 be the default */
56 	{{0x09,0x01}, /* SoftResetAll */
57 	 {0x09,0x00}, /* release reset */
58 	 {0x01,0xe8}, /* MSB of code rate 27.5MS/s */
59 	 {0x02,0x17}, /* middle byte " */
60 	 {0x03,0x29}, /* LSB         " */
61 	 {0x05,0x03}, /* @ DVB mode, standard code rate 3/4 */
62 	 {0x06,0xa5}, /* @ PLL 60MHz */
63 	 {0x07,0x01}, /* @ Fclk, i.e. sampling clock, 60MHz */
64 	 {0x0a,0x00}, /* @ partial chip disables, do not set */
65 	 {0x0b,0x01}, /* set output clock in gapped mode, start signal low
66 			 active for first byte */
67 	 {0x0c,0x11}, /* no parity bytes, large hold time, serial data out */
68 	 {0x0d,0x6f}, /* @ RS Sync/Unsync thresholds */
69 	 {0x10,0x40}, /* chip doc is misleading here: write bit 6 as 1
70 			 to avoid starting the BER counter. Reset the
71 			 CRC test bit. Finite counting selected */
72 	 {0x15,0xff}, /* @ size of the limited time window for RS BER
73 			 estimation. It is <value>*256 RS blocks, this
74 			 gives approx. 2.6 sec at 27.5MS/s, rate 3/4 */
75 	 {0x16,0x00}, /* @ enable all RS output ports */
76 	 {0x17,0x04}, /* @ time window allowed for the RS to sync */
77 	 {0x18,0xae}, /* @ allow all standard DVB code rates to be scanned
78 			 for automatically */
79 		      /* leave the current code rate and normalization
80 			 registers as they are after reset... */
81 	 {0x21,0x10}, /* @ during AutoAcq, search each viterbi setting
82 			 only once */
83 	 {0x23,0x18}, /* @ size of the limited time window for Viterbi BER
84 			 estimation. It is <value>*65536 channel bits, i.e.
85 			 approx. 38ms at 27.5MS/s, rate 3/4 */
86 	 {0x24,0x24}, /* do not trigger Viterbi CRC test. Finite count window */
87 		      /* leave front-end AGC parameters at default values */
88 		      /* leave decimation AGC parameters at default values */
89 	 {0x35,0x40}, /* disable all interrupts. They are not connected anyway */
90 	 {0x36,0xff}, /* clear all interrupt pending flags */
91 	 {0x37,0x00}, /* @ fully enable AutoAcqq state machine */
92 	 {0x38,0x07}, /* @ enable fade recovery, but not autostart AutoAcq */
93 		      /* leave the equalizer parameters on their default values */
94 		      /* leave the final AGC parameters on their default values */
95 	 {0x41,0x00}, /* @ MSB of front-end derotator frequency */
96 	 {0x42,0x00}, /* @ middle bytes " */
97 	 {0x43,0x00}, /* @ LSB          " */
98 		      /* leave the carrier tracking loop parameters on default */
99 		      /* leave the bit timing loop parameters at default */
100 	 {0x56,0x4d}, /* set the filtune voltage to 2.7V, as recommended by */
101 		      /* the cx24108 data sheet for symbol rates above 15MS/s */
102 	 {0x57,0x00}, /* @ Filter sigma delta enabled, positive */
103 	 {0x61,0x95}, /* GPIO pins 1-4 have special function */
104 	 {0x62,0x05}, /* GPIO pin 5 has special function, pin 6 is GPIO */
105 	 {0x63,0x00}, /* All GPIO pins use CMOS output characteristics */
106 	 {0x64,0x20}, /* GPIO 6 is input, all others are outputs */
107 	 {0x6d,0x30}, /* tuner auto mode clock freq 62kHz */
108 	 {0x70,0x15}, /* use auto mode, tuner word is 21 bits long */
109 	 {0x73,0x00}, /* @ disable several demod bypasses */
110 	 {0x74,0x00}, /* @  " */
111 	 {0x75,0x00}  /* @  " */
112 		      /* the remaining registers are for SEC */
113 	};
114 
115 
116 static int cx24110_writereg (struct cx24110_state* state, int reg, int data)
117 {
118 	u8 buf [] = { reg, data };
119 	struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf, .len = 2 };
120 	int err;
121 
122 	if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1) {
123 		dprintk("%s: writereg error (err == %i, reg == 0x%02x, data == 0x%02x)\n",
124 			__func__, err, reg, data);
125 		return -EREMOTEIO;
126 	}
127 
128 	return 0;
129 }
130 
131 static int cx24110_readreg (struct cx24110_state* state, u8 reg)
132 {
133 	int ret;
134 	u8 b0 [] = { reg };
135 	u8 b1 [] = { 0 };
136 	struct i2c_msg msg [] = { { .addr = state->config->demod_address, .flags = 0, .buf = b0, .len = 1 },
137 			   { .addr = state->config->demod_address, .flags = I2C_M_RD, .buf = b1, .len = 1 } };
138 
139 	ret = i2c_transfer(state->i2c, msg, 2);
140 
141 	if (ret != 2) return ret;
142 
143 	return b1[0];
144 }
145 
146 static int cx24110_set_inversion(struct cx24110_state *state,
147 				 enum fe_spectral_inversion inversion)
148 {
149 /* fixme (low): error handling */
150 
151 	switch (inversion) {
152 	case INVERSION_OFF:
153 		cx24110_writereg(state,0x37,cx24110_readreg(state,0x37)|0x1);
154 		/* AcqSpectrInvDis on. No idea why someone should want this */
155 		cx24110_writereg(state,0x5,cx24110_readreg(state,0x5)&0xf7);
156 		/* Initial value 0 at start of acq */
157 		cx24110_writereg(state,0x22,cx24110_readreg(state,0x22)&0xef);
158 		/* current value 0 */
159 		/* The cx24110 manual tells us this reg is read-only.
160 		   But what the heck... set it ayways */
161 		break;
162 	case INVERSION_ON:
163 		cx24110_writereg(state,0x37,cx24110_readreg(state,0x37)|0x1);
164 		/* AcqSpectrInvDis on. No idea why someone should want this */
165 		cx24110_writereg(state,0x5,cx24110_readreg(state,0x5)|0x08);
166 		/* Initial value 1 at start of acq */
167 		cx24110_writereg(state,0x22,cx24110_readreg(state,0x22)|0x10);
168 		/* current value 1 */
169 		break;
170 	case INVERSION_AUTO:
171 		cx24110_writereg(state,0x37,cx24110_readreg(state,0x37)&0xfe);
172 		/* AcqSpectrInvDis off. Leave initial & current states as is */
173 		break;
174 	default:
175 		return -EINVAL;
176 	}
177 
178 	return 0;
179 }
180 
181 static int cx24110_set_fec(struct cx24110_state *state, enum fe_code_rate fec)
182 {
183 	static const int rate[FEC_AUTO] = {-1,    1,    2,    3,    5,    7, -1};
184 	static const int g1[FEC_AUTO]   = {-1, 0x01, 0x02, 0x05, 0x15, 0x45, -1};
185 	static const int g2[FEC_AUTO]   = {-1, 0x01, 0x03, 0x06, 0x1a, 0x7a, -1};
186 
187 	/* Well, the AutoAcq engine of the cx24106 and 24110 automatically
188 	   searches all enabled viterbi rates, and can handle non-standard
189 	   rates as well. */
190 
191 	if (fec > FEC_AUTO)
192 		fec = FEC_AUTO;
193 
194 	if (fec == FEC_AUTO) { /* (re-)establish AutoAcq behaviour */
195 		cx24110_writereg(state, 0x37, cx24110_readreg(state, 0x37) & 0xdf);
196 		/* clear AcqVitDis bit */
197 		cx24110_writereg(state, 0x18, 0xae);
198 		/* allow all DVB standard code rates */
199 		cx24110_writereg(state, 0x05, (cx24110_readreg(state, 0x05) & 0xf0) | 0x3);
200 		/* set nominal Viterbi rate 3/4 */
201 		cx24110_writereg(state, 0x22, (cx24110_readreg(state, 0x22) & 0xf0) | 0x3);
202 		/* set current Viterbi rate 3/4 */
203 		cx24110_writereg(state, 0x1a, 0x05);
204 		cx24110_writereg(state, 0x1b, 0x06);
205 		/* set the puncture registers for code rate 3/4 */
206 		return 0;
207 	} else {
208 		cx24110_writereg(state, 0x37, cx24110_readreg(state, 0x37) | 0x20);
209 		/* set AcqVitDis bit */
210 		if (rate[fec] < 0)
211 			return -EINVAL;
212 
213 		cx24110_writereg(state, 0x05, (cx24110_readreg(state, 0x05) & 0xf0) | rate[fec]);
214 		/* set nominal Viterbi rate */
215 		cx24110_writereg(state, 0x22, (cx24110_readreg(state, 0x22) & 0xf0) | rate[fec]);
216 		/* set current Viterbi rate */
217 		cx24110_writereg(state, 0x1a, g1[fec]);
218 		cx24110_writereg(state, 0x1b, g2[fec]);
219 		/* not sure if this is the right way: I always used AutoAcq mode */
220 	}
221 	return 0;
222 }
223 
224 static enum fe_code_rate cx24110_get_fec(struct cx24110_state *state)
225 {
226 	int i;
227 
228 	i=cx24110_readreg(state,0x22)&0x0f;
229 	if(!(i&0x08)) {
230 		return FEC_1_2 + i - 1;
231 	} else {
232 /* fixme (low): a special code rate has been selected. In theory, we need to
233    return a denominator value, a numerator value, and a pair of puncture
234    maps to correctly describe this mode. But this should never happen in
235    practice, because it cannot be set by cx24110_get_fec. */
236 	   return FEC_NONE;
237 	}
238 }
239 
240 static int cx24110_set_symbolrate (struct cx24110_state* state, u32 srate)
241 {
242 /* fixme (low): add error handling */
243 	u32 ratio;
244 	u32 tmp, fclk, BDRI;
245 
246 	static const u32 bands[]={5000000UL,15000000UL,90999000UL/2};
247 	int i;
248 
249 	dprintk("cx24110 debug: entering %s(%d)\n",__func__,srate);
250 	if (srate>90999000UL/2)
251 		srate=90999000UL/2;
252 	if (srate<500000)
253 		srate=500000;
254 
255 	for(i = 0; (i < ARRAY_SIZE(bands)) && (srate>bands[i]); i++)
256 		;
257 	/* first, check which sample rate is appropriate: 45, 60 80 or 90 MHz,
258 	   and set the PLL accordingly (R07[1:0] Fclk, R06[7:4] PLLmult,
259 	   R06[3:0] PLLphaseDetGain */
260 	tmp=cx24110_readreg(state,0x07)&0xfc;
261 	if(srate<90999000UL/4) { /* sample rate 45MHz*/
262 		cx24110_writereg(state,0x07,tmp);
263 		cx24110_writereg(state,0x06,0x78);
264 		fclk=90999000UL/2;
265 	} else if(srate<60666000UL/2) { /* sample rate 60MHz */
266 		cx24110_writereg(state,0x07,tmp|0x1);
267 		cx24110_writereg(state,0x06,0xa5);
268 		fclk=60666000UL;
269 	} else if(srate<80888000UL/2) { /* sample rate 80MHz */
270 		cx24110_writereg(state,0x07,tmp|0x2);
271 		cx24110_writereg(state,0x06,0x87);
272 		fclk=80888000UL;
273 	} else { /* sample rate 90MHz */
274 		cx24110_writereg(state,0x07,tmp|0x3);
275 		cx24110_writereg(state,0x06,0x78);
276 		fclk=90999000UL;
277 	}
278 	dprintk("cx24110 debug: fclk %d Hz\n",fclk);
279 	/* we need to divide two integers with approx. 27 bits in 32 bit
280 	   arithmetic giving a 25 bit result */
281 	/* the maximum dividend is 90999000/2, 0x02b6446c, this number is
282 	   also the most complex divisor. Hence, the dividend has,
283 	   assuming 32bit unsigned arithmetic, 6 clear bits on top, the
284 	   divisor 2 unused bits at the bottom. Also, the quotient is
285 	   always less than 1/2. Borrowed from VES1893.c, of course */
286 
287 	tmp=srate<<6;
288 	BDRI=fclk>>2;
289 	ratio=(tmp/BDRI);
290 
291 	tmp=(tmp%BDRI)<<8;
292 	ratio=(ratio<<8)+(tmp/BDRI);
293 
294 	tmp=(tmp%BDRI)<<8;
295 	ratio=(ratio<<8)+(tmp/BDRI);
296 
297 	tmp=(tmp%BDRI)<<1;
298 	ratio=(ratio<<1)+(tmp/BDRI);
299 
300 	dprintk("srate= %d (range %d, up to %d)\n", srate,i,bands[i]);
301 	dprintk("fclk = %d\n", fclk);
302 	dprintk("ratio= %08x\n", ratio);
303 
304 	cx24110_writereg(state, 0x1, (ratio>>16)&0xff);
305 	cx24110_writereg(state, 0x2, (ratio>>8)&0xff);
306 	cx24110_writereg(state, 0x3, (ratio)&0xff);
307 
308 	return 0;
309 
310 }
311 
312 static int _cx24110_pll_write (struct dvb_frontend* fe, const u8 buf[], int len)
313 {
314 	struct cx24110_state *state = fe->demodulator_priv;
315 
316 	if (len != 3)
317 		return -EINVAL;
318 
319 /* tuner data is 21 bits long, must be left-aligned in data */
320 /* tuner cx24108 is written through a dedicated 3wire interface on the demod chip */
321 /* FIXME (low): add error handling, avoid infinite loops if HW fails... */
322 
323 	cx24110_writereg(state,0x6d,0x30); /* auto mode at 62kHz */
324 	cx24110_writereg(state,0x70,0x15); /* auto mode 21 bits */
325 
326 	/* if the auto tuner writer is still busy, clear it out */
327 	while (cx24110_readreg(state,0x6d)&0x80)
328 		cx24110_writereg(state,0x72,0);
329 
330 	/* write the topmost 8 bits */
331 	cx24110_writereg(state,0x72,buf[0]);
332 
333 	/* wait for the send to be completed */
334 	while ((cx24110_readreg(state,0x6d)&0xc0)==0x80)
335 		;
336 
337 	/* send another 8 bytes */
338 	cx24110_writereg(state,0x72,buf[1]);
339 	while ((cx24110_readreg(state,0x6d)&0xc0)==0x80)
340 		;
341 
342 	/* and the topmost 5 bits of this byte */
343 	cx24110_writereg(state,0x72,buf[2]);
344 	while ((cx24110_readreg(state,0x6d)&0xc0)==0x80)
345 		;
346 
347 	/* now strobe the enable line once */
348 	cx24110_writereg(state,0x6d,0x32);
349 	cx24110_writereg(state,0x6d,0x30);
350 
351 	return 0;
352 }
353 
354 static int cx24110_initfe(struct dvb_frontend* fe)
355 {
356 	struct cx24110_state *state = fe->demodulator_priv;
357 /* fixme (low): error handling */
358 	int i;
359 
360 	dprintk("%s: init chip\n", __func__);
361 
362 	for(i = 0; i < ARRAY_SIZE(cx24110_regdata); i++) {
363 		cx24110_writereg(state, cx24110_regdata[i].reg, cx24110_regdata[i].data);
364 	}
365 
366 	return 0;
367 }
368 
369 static int cx24110_set_voltage(struct dvb_frontend *fe,
370 			       enum fe_sec_voltage voltage)
371 {
372 	struct cx24110_state *state = fe->demodulator_priv;
373 
374 	switch (voltage) {
375 	case SEC_VOLTAGE_13:
376 		return cx24110_writereg(state,0x76,(cx24110_readreg(state,0x76)&0x3b)|0xc0);
377 	case SEC_VOLTAGE_18:
378 		return cx24110_writereg(state,0x76,(cx24110_readreg(state,0x76)&0x3b)|0x40);
379 	default:
380 		return -EINVAL;
381 	}
382 }
383 
384 static int cx24110_diseqc_send_burst(struct dvb_frontend *fe,
385 				     enum fe_sec_mini_cmd burst)
386 {
387 	int rv, bit;
388 	struct cx24110_state *state = fe->demodulator_priv;
389 	unsigned long timeout;
390 
391 	if (burst == SEC_MINI_A)
392 		bit = 0x00;
393 	else if (burst == SEC_MINI_B)
394 		bit = 0x08;
395 	else
396 		return -EINVAL;
397 
398 	rv = cx24110_readreg(state, 0x77);
399 	if (!(rv & 0x04))
400 		cx24110_writereg(state, 0x77, rv | 0x04);
401 
402 	rv = cx24110_readreg(state, 0x76);
403 	cx24110_writereg(state, 0x76, ((rv & 0x90) | 0x40 | bit));
404 	timeout = jiffies + msecs_to_jiffies(100);
405 	while (!time_after(jiffies, timeout) && !(cx24110_readreg(state, 0x76) & 0x40))
406 		; /* wait for LNB ready */
407 
408 	return 0;
409 }
410 
411 static int cx24110_send_diseqc_msg(struct dvb_frontend* fe,
412 				   struct dvb_diseqc_master_cmd *cmd)
413 {
414 	int i, rv;
415 	struct cx24110_state *state = fe->demodulator_priv;
416 	unsigned long timeout;
417 
418 	if (cmd->msg_len < 3 || cmd->msg_len > 6)
419 		return -EINVAL;  /* not implemented */
420 
421 	for (i = 0; i < cmd->msg_len; i++)
422 		cx24110_writereg(state, 0x79 + i, cmd->msg[i]);
423 
424 	rv = cx24110_readreg(state, 0x77);
425 	if (rv & 0x04) {
426 		cx24110_writereg(state, 0x77, rv & ~0x04);
427 		msleep(30); /* reportedly fixes switching problems */
428 	}
429 
430 	rv = cx24110_readreg(state, 0x76);
431 
432 	cx24110_writereg(state, 0x76, ((rv & 0x90) | 0x40) | ((cmd->msg_len-3) & 3));
433 	timeout = jiffies + msecs_to_jiffies(100);
434 	while (!time_after(jiffies, timeout) && !(cx24110_readreg(state, 0x76) & 0x40))
435 		; /* wait for LNB ready */
436 
437 	return 0;
438 }
439 
440 static int cx24110_read_status(struct dvb_frontend *fe,
441 			       enum fe_status *status)
442 {
443 	struct cx24110_state *state = fe->demodulator_priv;
444 
445 	int sync = cx24110_readreg (state, 0x55);
446 
447 	*status = 0;
448 
449 	if (sync & 0x10)
450 		*status |= FE_HAS_SIGNAL;
451 
452 	if (sync & 0x08)
453 		*status |= FE_HAS_CARRIER;
454 
455 	sync = cx24110_readreg (state, 0x08);
456 
457 	if (sync & 0x40)
458 		*status |= FE_HAS_VITERBI;
459 
460 	if (sync & 0x20)
461 		*status |= FE_HAS_SYNC;
462 
463 	if ((sync & 0x60) == 0x60)
464 		*status |= FE_HAS_LOCK;
465 
466 	return 0;
467 }
468 
469 static int cx24110_read_ber(struct dvb_frontend* fe, u32* ber)
470 {
471 	struct cx24110_state *state = fe->demodulator_priv;
472 
473 	/* fixme (maybe): value range is 16 bit. Scale? */
474 	if(cx24110_readreg(state,0x24)&0x10) {
475 		/* the Viterbi error counter has finished one counting window */
476 		cx24110_writereg(state,0x24,0x04); /* select the ber reg */
477 		state->lastber=cx24110_readreg(state,0x25)|
478 			(cx24110_readreg(state,0x26)<<8);
479 		cx24110_writereg(state,0x24,0x04); /* start new count window */
480 		cx24110_writereg(state,0x24,0x14);
481 	}
482 	*ber = state->lastber;
483 
484 	return 0;
485 }
486 
487 static int cx24110_read_signal_strength(struct dvb_frontend* fe, u16* signal_strength)
488 {
489 	struct cx24110_state *state = fe->demodulator_priv;
490 
491 /* no provision in hardware. Read the frontend AGC accumulator. No idea how to scale this, but I know it is 2s complement */
492 	u8 signal = cx24110_readreg (state, 0x27)+128;
493 	*signal_strength = (signal << 8) | signal;
494 
495 	return 0;
496 }
497 
498 static int cx24110_read_snr(struct dvb_frontend* fe, u16* snr)
499 {
500 	struct cx24110_state *state = fe->demodulator_priv;
501 
502 	/* no provision in hardware. Can be computed from the Es/N0 estimator, but I don't know how. */
503 	if(cx24110_readreg(state,0x6a)&0x80) {
504 		/* the Es/N0 error counter has finished one counting window */
505 		state->lastesn0=cx24110_readreg(state,0x69)|
506 			(cx24110_readreg(state,0x68)<<8);
507 		cx24110_writereg(state,0x6a,0x84); /* start new count window */
508 	}
509 	*snr = state->lastesn0;
510 
511 	return 0;
512 }
513 
514 static int cx24110_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
515 {
516 	struct cx24110_state *state = fe->demodulator_priv;
517 
518 	if(cx24110_readreg(state,0x10)&0x40) {
519 		/* the RS error counter has finished one counting window */
520 		cx24110_writereg(state,0x10,0x60); /* select the byer reg */
521 		(void)(cx24110_readreg(state, 0x12) |
522 			(cx24110_readreg(state, 0x13) << 8) |
523 			(cx24110_readreg(state, 0x14) << 16));
524 		cx24110_writereg(state,0x10,0x70); /* select the bler reg */
525 		state->lastbler=cx24110_readreg(state,0x12)|
526 			(cx24110_readreg(state,0x13)<<8)|
527 			(cx24110_readreg(state,0x14)<<16);
528 		cx24110_writereg(state,0x10,0x20); /* start new count window */
529 	}
530 	*ucblocks = state->lastbler;
531 
532 	return 0;
533 }
534 
535 static int cx24110_set_frontend(struct dvb_frontend *fe)
536 {
537 	struct cx24110_state *state = fe->demodulator_priv;
538 	struct dtv_frontend_properties *p = &fe->dtv_property_cache;
539 
540 	if (fe->ops.tuner_ops.set_params) {
541 		fe->ops.tuner_ops.set_params(fe);
542 		if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
543 	}
544 
545 	cx24110_set_inversion(state, p->inversion);
546 	cx24110_set_fec(state, p->fec_inner);
547 	cx24110_set_symbolrate(state, p->symbol_rate);
548 	cx24110_writereg(state,0x04,0x05); /* start acquisition */
549 
550 	return 0;
551 }
552 
553 static int cx24110_get_frontend(struct dvb_frontend *fe,
554 				struct dtv_frontend_properties *p)
555 {
556 	struct cx24110_state *state = fe->demodulator_priv;
557 	s32 afc; unsigned sclk;
558 
559 /* cannot read back tuner settings (freq). Need to have some private storage */
560 
561 	sclk = cx24110_readreg (state, 0x07) & 0x03;
562 /* ok, real AFC (FEDR) freq. is afc/2^24*fsamp, fsamp=45/60/80/90MHz.
563  * Need 64 bit arithmetic. Is thiss possible in the kernel? */
564 	if (sclk==0) sclk=90999000L/2L;
565 	else if (sclk==1) sclk=60666000L;
566 	else if (sclk==2) sclk=80888000L;
567 	else sclk=90999000L;
568 	sclk>>=8;
569 	afc = sclk*(cx24110_readreg (state, 0x44)&0x1f)+
570 	      ((sclk*cx24110_readreg (state, 0x45))>>8)+
571 	      ((sclk*cx24110_readreg (state, 0x46))>>16);
572 
573 	p->frequency += afc;
574 	p->inversion = (cx24110_readreg (state, 0x22) & 0x10) ?
575 				INVERSION_ON : INVERSION_OFF;
576 	p->fec_inner = cx24110_get_fec(state);
577 
578 	return 0;
579 }
580 
581 static int cx24110_set_tone(struct dvb_frontend *fe,
582 			    enum fe_sec_tone_mode tone)
583 {
584 	struct cx24110_state *state = fe->demodulator_priv;
585 
586 	return cx24110_writereg(state,0x76,(cx24110_readreg(state,0x76)&~0x10)|(((tone==SEC_TONE_ON))?0x10:0));
587 }
588 
589 static void cx24110_release(struct dvb_frontend* fe)
590 {
591 	struct cx24110_state* state = fe->demodulator_priv;
592 	kfree(state);
593 }
594 
595 static const struct dvb_frontend_ops cx24110_ops;
596 
597 struct dvb_frontend* cx24110_attach(const struct cx24110_config* config,
598 				    struct i2c_adapter* i2c)
599 {
600 	struct cx24110_state* state = NULL;
601 	int ret;
602 
603 	/* allocate memory for the internal state */
604 	state = kzalloc(sizeof(struct cx24110_state), GFP_KERNEL);
605 	if (state == NULL) goto error;
606 
607 	/* setup the state */
608 	state->config = config;
609 	state->i2c = i2c;
610 	state->lastber = 0;
611 	state->lastbler = 0;
612 	state->lastesn0 = 0;
613 
614 	/* check if the demod is there */
615 	ret = cx24110_readreg(state, 0x00);
616 	if ((ret != 0x5a) && (ret != 0x69)) goto error;
617 
618 	/* create dvb_frontend */
619 	memcpy(&state->frontend.ops, &cx24110_ops, sizeof(struct dvb_frontend_ops));
620 	state->frontend.demodulator_priv = state;
621 	return &state->frontend;
622 
623 error:
624 	kfree(state);
625 	return NULL;
626 }
627 
628 static const struct dvb_frontend_ops cx24110_ops = {
629 	.delsys = { SYS_DVBS },
630 	.info = {
631 		.name = "Conexant CX24110 DVB-S",
632 		.frequency_min = 950000,
633 		.frequency_max = 2150000,
634 		.frequency_stepsize = 1011,  /* kHz for QPSK frontends */
635 		.frequency_tolerance = 29500,
636 		.symbol_rate_min = 1000000,
637 		.symbol_rate_max = 45000000,
638 		.caps = FE_CAN_INVERSION_AUTO |
639 			FE_CAN_FEC_1_2 | FE_CAN_FEC_2_3 | FE_CAN_FEC_3_4 |
640 			FE_CAN_FEC_5_6 | FE_CAN_FEC_7_8 | FE_CAN_FEC_AUTO |
641 			FE_CAN_QPSK | FE_CAN_RECOVER
642 	},
643 
644 	.release = cx24110_release,
645 
646 	.init = cx24110_initfe,
647 	.write = _cx24110_pll_write,
648 	.set_frontend = cx24110_set_frontend,
649 	.get_frontend = cx24110_get_frontend,
650 	.read_status = cx24110_read_status,
651 	.read_ber = cx24110_read_ber,
652 	.read_signal_strength = cx24110_read_signal_strength,
653 	.read_snr = cx24110_read_snr,
654 	.read_ucblocks = cx24110_read_ucblocks,
655 
656 	.diseqc_send_master_cmd = cx24110_send_diseqc_msg,
657 	.set_tone = cx24110_set_tone,
658 	.set_voltage = cx24110_set_voltage,
659 	.diseqc_send_burst = cx24110_diseqc_send_burst,
660 };
661 
662 module_param(debug, int, 0644);
663 MODULE_PARM_DESC(debug, "Turn on/off frontend debugging (default:off).");
664 
665 MODULE_DESCRIPTION("Conexant CX24110 DVB-S Demodulator driver");
666 MODULE_AUTHOR("Peter Hettkamp");
667 MODULE_LICENSE("GPL");
668 
669 EXPORT_SYMBOL(cx24110_attach);
670