Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux-2.6
[pandora-kernel.git] / drivers / media / dvb / frontends / lgdt330x.c
1 /*
2  *    Support for LGDT3302 and LGDT3303 - VSB/QAM
3  *
4  *    Copyright (C) 2005 Wilson Michaels <wilsonmichaels@earthlink.net>
5  *
6  *    This program is free software; you can redistribute it and/or modify
7  *    it under the terms of the GNU General Public License as published by
8  *    the Free Software Foundation; either version 2 of the License, or
9  *    (at your option) any later version.
10  *
11  *    This program is distributed in the hope that it will be useful,
12  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *    GNU General Public License for more details.
15  *
16  *    You should have received a copy of the GNU General Public License
17  *    along with this program; if not, write to the Free Software
18  *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19  *
20  */
21
22 /*
23  *                      NOTES ABOUT THIS DRIVER
24  *
25  * This Linux driver supports:
26  *   DViCO FusionHDTV 3 Gold-Q
27  *   DViCO FusionHDTV 3 Gold-T
28  *   DViCO FusionHDTV 5 Gold
29  *   DViCO FusionHDTV 5 Lite
30  *   DViCO FusionHDTV 5 USB Gold
31  *   Air2PC/AirStar 2 ATSC 3rd generation (HD5000)
32  *   pcHDTV HD5500
33  *
34  */
35
36 #include <linux/kernel.h>
37 #include <linux/module.h>
38 #include <linux/init.h>
39 #include <linux/delay.h>
40 #include <linux/string.h>
41 #include <linux/slab.h>
42 #include <asm/byteorder.h>
43
44 #include "dvb_frontend.h"
45 #include "dvb_math.h"
46 #include "lgdt330x_priv.h"
47 #include "lgdt330x.h"
48
49 /* Use Equalizer Mean Squared Error instead of Phaser Tracker MSE */
50 /* #define USE_EQMSE */
51
52 static int debug;
53 module_param(debug, int, 0644);
54 MODULE_PARM_DESC(debug,"Turn on/off lgdt330x frontend debugging (default:off).");
55 #define dprintk(args...) \
56 do { \
57 if (debug) printk(KERN_DEBUG "lgdt330x: " args); \
58 } while (0)
59
60 struct lgdt330x_state
61 {
62         struct i2c_adapter* i2c;
63
64         /* Configuration settings */
65         const struct lgdt330x_config* config;
66
67         struct dvb_frontend frontend;
68
69         /* Demodulator private data */
70         fe_modulation_t current_modulation;
71         u32 snr; /* Result of last SNR calculation */
72
73         /* Tuner private data */
74         u32 current_frequency;
75 };
76
77 static int i2c_write_demod_bytes (struct lgdt330x_state* state,
78                                   u8 *buf, /* data bytes to send */
79                                   int len  /* number of bytes to send */ )
80 {
81         struct i2c_msg msg =
82                 { .addr = state->config->demod_address,
83                   .flags = 0,
84                   .buf = buf,
85                   .len = 2 };
86         int i;
87         int err;
88
89         for (i=0; i<len-1; i+=2){
90                 if ((err = i2c_transfer(state->i2c, &msg, 1)) != 1) {
91                         printk(KERN_WARNING "lgdt330x: %s error (addr %02x <- %02x, err = %i)\n", __func__, msg.buf[0], msg.buf[1], err);
92                         if (err < 0)
93                                 return err;
94                         else
95                                 return -EREMOTEIO;
96                 }
97                 msg.buf += 2;
98         }
99         return 0;
100 }
101
102 /*
103  * This routine writes the register (reg) to the demod bus
104  * then reads the data returned for (len) bytes.
105  */
106
107 static u8 i2c_read_demod_bytes (struct lgdt330x_state* state,
108                                enum I2C_REG reg, u8* buf, int len)
109 {
110         u8 wr [] = { reg };
111         struct i2c_msg msg [] = {
112                 { .addr = state->config->demod_address,
113                   .flags = 0, .buf = wr,  .len = 1 },
114                 { .addr = state->config->demod_address,
115                   .flags = I2C_M_RD, .buf = buf, .len = len },
116         };
117         int ret;
118         ret = i2c_transfer(state->i2c, msg, 2);
119         if (ret != 2) {
120                 printk(KERN_WARNING "lgdt330x: %s: addr 0x%02x select 0x%02x error (ret == %i)\n", __func__, state->config->demod_address, reg, ret);
121         } else {
122                 ret = 0;
123         }
124         return ret;
125 }
126
127 /* Software reset */
128 static int lgdt3302_SwReset(struct lgdt330x_state* state)
129 {
130         u8 ret;
131         u8 reset[] = {
132                 IRQ_MASK,
133                 0x00 /* bit 6 is active low software reset
134                       * bits 5-0 are 1 to mask interrupts */
135         };
136
137         ret = i2c_write_demod_bytes(state,
138                                     reset, sizeof(reset));
139         if (ret == 0) {
140
141                 /* force reset high (inactive) and unmask interrupts */
142                 reset[1] = 0x7f;
143                 ret = i2c_write_demod_bytes(state,
144                                             reset, sizeof(reset));
145         }
146         return ret;
147 }
148
149 static int lgdt3303_SwReset(struct lgdt330x_state* state)
150 {
151         u8 ret;
152         u8 reset[] = {
153                 0x02,
154                 0x00 /* bit 0 is active low software reset */
155         };
156
157         ret = i2c_write_demod_bytes(state,
158                                     reset, sizeof(reset));
159         if (ret == 0) {
160
161                 /* force reset high (inactive) */
162                 reset[1] = 0x01;
163                 ret = i2c_write_demod_bytes(state,
164                                             reset, sizeof(reset));
165         }
166         return ret;
167 }
168
169 static int lgdt330x_SwReset(struct lgdt330x_state* state)
170 {
171         switch (state->config->demod_chip) {
172         case LGDT3302:
173                 return lgdt3302_SwReset(state);
174         case LGDT3303:
175                 return lgdt3303_SwReset(state);
176         default:
177                 return -ENODEV;
178         }
179 }
180
181 static int lgdt330x_init(struct dvb_frontend* fe)
182 {
183         /* Hardware reset is done using gpio[0] of cx23880x chip.
184          * I'd like to do it here, but don't know how to find chip address.
185          * cx88-cards.c arranges for the reset bit to be inactive (high).
186          * Maybe there needs to be a callable function in cx88-core or
187          * the caller of this function needs to do it. */
188
189         /*
190          * Array of byte pairs <address, value>
191          * to initialize each different chip
192          */
193         static u8 lgdt3302_init_data[] = {
194                 /* Use 50MHz parameter values from spec sheet since xtal is 50 */
195                 /* Change the value of NCOCTFV[25:0] of carrier
196                    recovery center frequency register */
197                 VSB_CARRIER_FREQ0, 0x00,
198                 VSB_CARRIER_FREQ1, 0x87,
199                 VSB_CARRIER_FREQ2, 0x8e,
200                 VSB_CARRIER_FREQ3, 0x01,
201                 /* Change the TPCLK pin polarity
202                    data is valid on falling clock */
203                 DEMUX_CONTROL, 0xfb,
204                 /* Change the value of IFBW[11:0] of
205                    AGC IF/RF loop filter bandwidth register */
206                 AGC_RF_BANDWIDTH0, 0x40,
207                 AGC_RF_BANDWIDTH1, 0x93,
208                 AGC_RF_BANDWIDTH2, 0x00,
209                 /* Change the value of bit 6, 'nINAGCBY' and
210                    'NSSEL[1:0] of ACG function control register 2 */
211                 AGC_FUNC_CTRL2, 0xc6,
212                 /* Change the value of bit 6 'RFFIX'
213                    of AGC function control register 3 */
214                 AGC_FUNC_CTRL3, 0x40,
215                 /* Set the value of 'INLVTHD' register 0x2a/0x2c
216                    to 0x7fe */
217                 AGC_DELAY0, 0x07,
218                 AGC_DELAY2, 0xfe,
219                 /* Change the value of IAGCBW[15:8]
220                    of inner AGC loop filter bandwidth */
221                 AGC_LOOP_BANDWIDTH0, 0x08,
222                 AGC_LOOP_BANDWIDTH1, 0x9a
223         };
224
225         static u8 lgdt3303_init_data[] = {
226                 0x4c, 0x14
227         };
228
229         static u8 flip_lgdt3303_init_data[] = {
230                 0x4c, 0x14,
231                 0x87, 0xf3
232         };
233
234         struct lgdt330x_state* state = fe->demodulator_priv;
235         char  *chip_name;
236         int    err;
237
238         switch (state->config->demod_chip) {
239         case LGDT3302:
240                 chip_name = "LGDT3302";
241                 err = i2c_write_demod_bytes(state, lgdt3302_init_data,
242                                             sizeof(lgdt3302_init_data));
243                 break;
244         case LGDT3303:
245                 chip_name = "LGDT3303";
246                 if (state->config->clock_polarity_flip) {
247                         err = i2c_write_demod_bytes(state, flip_lgdt3303_init_data,
248                                                     sizeof(flip_lgdt3303_init_data));
249                 } else {
250                         err = i2c_write_demod_bytes(state, lgdt3303_init_data,
251                                                     sizeof(lgdt3303_init_data));
252                 }
253                 break;
254         default:
255                 chip_name = "undefined";
256                 printk (KERN_WARNING "Only LGDT3302 and LGDT3303 are supported chips.\n");
257                 err = -ENODEV;
258         }
259         dprintk("%s entered as %s\n", __func__, chip_name);
260         if (err < 0)
261                 return err;
262         return lgdt330x_SwReset(state);
263 }
264
265 static int lgdt330x_read_ber(struct dvb_frontend* fe, u32* ber)
266 {
267         *ber = 0; /* Not supplied by the demod chips */
268         return 0;
269 }
270
271 static int lgdt330x_read_ucblocks(struct dvb_frontend* fe, u32* ucblocks)
272 {
273         struct lgdt330x_state* state = fe->demodulator_priv;
274         int err;
275         u8 buf[2];
276
277         switch (state->config->demod_chip) {
278         case LGDT3302:
279                 err = i2c_read_demod_bytes(state, LGDT3302_PACKET_ERR_COUNTER1,
280                                            buf, sizeof(buf));
281                 break;
282         case LGDT3303:
283                 err = i2c_read_demod_bytes(state, LGDT3303_PACKET_ERR_COUNTER1,
284                                            buf, sizeof(buf));
285                 break;
286         default:
287                 printk(KERN_WARNING
288                        "Only LGDT3302 and LGDT3303 are supported chips.\n");
289                 err = -ENODEV;
290         }
291
292         *ucblocks = (buf[0] << 8) | buf[1];
293         return 0;
294 }
295
296 static int lgdt330x_set_parameters(struct dvb_frontend* fe,
297                                    struct dvb_frontend_parameters *param)
298 {
299         /*
300          * Array of byte pairs <address, value>
301          * to initialize 8VSB for lgdt3303 chip 50 MHz IF
302          */
303         static u8 lgdt3303_8vsb_44_data[] = {
304                 0x04, 0x00,
305                 0x0d, 0x40,
306                 0x0e, 0x87,
307                 0x0f, 0x8e,
308                 0x10, 0x01,
309                 0x47, 0x8b };
310
311         /*
312          * Array of byte pairs <address, value>
313          * to initialize QAM for lgdt3303 chip
314          */
315         static u8 lgdt3303_qam_data[] = {
316                 0x04, 0x00,
317                 0x0d, 0x00,
318                 0x0e, 0x00,
319                 0x0f, 0x00,
320                 0x10, 0x00,
321                 0x51, 0x63,
322                 0x47, 0x66,
323                 0x48, 0x66,
324                 0x4d, 0x1a,
325                 0x49, 0x08,
326                 0x4a, 0x9b };
327
328         struct lgdt330x_state* state = fe->demodulator_priv;
329
330         static u8 top_ctrl_cfg[]   = { TOP_CONTROL, 0x03 };
331
332         int err;
333         /* Change only if we are actually changing the modulation */
334         if (state->current_modulation != param->u.vsb.modulation) {
335                 switch(param->u.vsb.modulation) {
336                 case VSB_8:
337                         dprintk("%s: VSB_8 MODE\n", __func__);
338
339                         /* Select VSB mode */
340                         top_ctrl_cfg[1] = 0x03;
341
342                         /* Select ANT connector if supported by card */
343                         if (state->config->pll_rf_set)
344                                 state->config->pll_rf_set(fe, 1);
345
346                         if (state->config->demod_chip == LGDT3303) {
347                                 err = i2c_write_demod_bytes(state, lgdt3303_8vsb_44_data,
348                                                             sizeof(lgdt3303_8vsb_44_data));
349                         }
350                         break;
351
352                 case QAM_64:
353                         dprintk("%s: QAM_64 MODE\n", __func__);
354
355                         /* Select QAM_64 mode */
356                         top_ctrl_cfg[1] = 0x00;
357
358                         /* Select CABLE connector if supported by card */
359                         if (state->config->pll_rf_set)
360                                 state->config->pll_rf_set(fe, 0);
361
362                         if (state->config->demod_chip == LGDT3303) {
363                                 err = i2c_write_demod_bytes(state, lgdt3303_qam_data,
364                                                                                         sizeof(lgdt3303_qam_data));
365                         }
366                         break;
367
368                 case QAM_256:
369                         dprintk("%s: QAM_256 MODE\n", __func__);
370
371                         /* Select QAM_256 mode */
372                         top_ctrl_cfg[1] = 0x01;
373
374                         /* Select CABLE connector if supported by card */
375                         if (state->config->pll_rf_set)
376                                 state->config->pll_rf_set(fe, 0);
377
378                         if (state->config->demod_chip == LGDT3303) {
379                                 err = i2c_write_demod_bytes(state, lgdt3303_qam_data,
380                                                                                         sizeof(lgdt3303_qam_data));
381                         }
382                         break;
383                 default:
384                         printk(KERN_WARNING "lgdt330x: %s: Modulation type(%d) UNSUPPORTED\n", __func__, param->u.vsb.modulation);
385                         return -1;
386                 }
387                 /*
388                  * select serial or parallel MPEG harware interface
389                  * Serial:   0x04 for LGDT3302 or 0x40 for LGDT3303
390                  * Parallel: 0x00
391                  */
392                 top_ctrl_cfg[1] |= state->config->serial_mpeg;
393
394                 /* Select the requested mode */
395                 i2c_write_demod_bytes(state, top_ctrl_cfg,
396                                       sizeof(top_ctrl_cfg));
397                 if (state->config->set_ts_params)
398                         state->config->set_ts_params(fe, 0);
399                 state->current_modulation = param->u.vsb.modulation;
400         }
401
402         /* Tune to the specified frequency */
403         if (fe->ops.tuner_ops.set_params) {
404                 fe->ops.tuner_ops.set_params(fe, param);
405                 if (fe->ops.i2c_gate_ctrl) fe->ops.i2c_gate_ctrl(fe, 0);
406         }
407
408         /* Keep track of the new frequency */
409         /* FIXME this is the wrong way to do this...           */
410         /* The tuner is shared with the video4linux analog API */
411         state->current_frequency = param->frequency;
412
413         lgdt330x_SwReset(state);
414         return 0;
415 }
416
417 static int lgdt330x_get_frontend(struct dvb_frontend* fe,
418                                  struct dvb_frontend_parameters* param)
419 {
420         struct lgdt330x_state *state = fe->demodulator_priv;
421         param->frequency = state->current_frequency;
422         return 0;
423 }
424
425 static int lgdt3302_read_status(struct dvb_frontend* fe, fe_status_t* status)
426 {
427         struct lgdt330x_state* state = fe->demodulator_priv;
428         u8 buf[3];
429
430         *status = 0; /* Reset status result */
431
432         /* AGC status register */
433         i2c_read_demod_bytes(state, AGC_STATUS, buf, 1);
434         dprintk("%s: AGC_STATUS = 0x%02x\n", __func__, buf[0]);
435         if ((buf[0] & 0x0c) == 0x8){
436                 /* Test signal does not exist flag */
437                 /* as well as the AGC lock flag.   */
438                 *status |= FE_HAS_SIGNAL;
439         }
440
441         /*
442          * You must set the Mask bits to 1 in the IRQ_MASK in order
443          * to see that status bit in the IRQ_STATUS register.
444          * This is done in SwReset();
445          */
446         /* signal status */
447         i2c_read_demod_bytes(state, TOP_CONTROL, buf, sizeof(buf));
448         dprintk("%s: TOP_CONTROL = 0x%02x, IRO_MASK = 0x%02x, IRQ_STATUS = 0x%02x\n", __func__, buf[0], buf[1], buf[2]);
449
450
451         /* sync status */
452         if ((buf[2] & 0x03) == 0x01) {
453                 *status |= FE_HAS_SYNC;
454         }
455
456         /* FEC error status */
457         if ((buf[2] & 0x0c) == 0x08) {
458                 *status |= FE_HAS_LOCK;
459                 *status |= FE_HAS_VITERBI;
460         }
461
462         /* Carrier Recovery Lock Status Register */
463         i2c_read_demod_bytes(state, CARRIER_LOCK, buf, 1);
464         dprintk("%s: CARRIER_LOCK = 0x%02x\n", __func__, buf[0]);
465         switch (state->current_modulation) {
466         case QAM_256:
467         case QAM_64:
468                 /* Need to undestand why there are 3 lock levels here */
469                 if ((buf[0] & 0x07) == 0x07)
470                         *status |= FE_HAS_CARRIER;
471                 break;
472         case VSB_8:
473                 if ((buf[0] & 0x80) == 0x80)
474                         *status |= FE_HAS_CARRIER;
475                 break;
476         default:
477                 printk(KERN_WARNING "lgdt330x: %s: Modulation set to unsupported value\n", __func__);
478         }
479
480         return 0;
481 }
482
483 static int lgdt3303_read_status(struct dvb_frontend* fe, fe_status_t* status)
484 {
485         struct lgdt330x_state* state = fe->demodulator_priv;
486         int err;
487         u8 buf[3];
488
489         *status = 0; /* Reset status result */
490
491         /* lgdt3303 AGC status register */
492         err = i2c_read_demod_bytes(state, 0x58, buf, 1);
493         if (err < 0)
494                 return err;
495
496         dprintk("%s: AGC_STATUS = 0x%02x\n", __func__, buf[0]);
497         if ((buf[0] & 0x21) == 0x01){
498                 /* Test input signal does not exist flag */
499                 /* as well as the AGC lock flag.   */
500                 *status |= FE_HAS_SIGNAL;
501         }
502
503         /* Carrier Recovery Lock Status Register */
504         i2c_read_demod_bytes(state, CARRIER_LOCK, buf, 1);
505         dprintk("%s: CARRIER_LOCK = 0x%02x\n", __func__, buf[0]);
506         switch (state->current_modulation) {
507         case QAM_256:
508         case QAM_64:
509                 /* Need to undestand why there are 3 lock levels here */
510                 if ((buf[0] & 0x07) == 0x07)
511                         *status |= FE_HAS_CARRIER;
512                 else
513                         break;
514                 i2c_read_demod_bytes(state, 0x8a, buf, 1);
515                 if ((buf[0] & 0x04) == 0x04)
516                         *status |= FE_HAS_SYNC;
517                 if ((buf[0] & 0x01) == 0x01)
518                         *status |= FE_HAS_LOCK;
519                 if ((buf[0] & 0x08) == 0x08)
520                         *status |= FE_HAS_VITERBI;
521                 break;
522         case VSB_8:
523                 if ((buf[0] & 0x80) == 0x80)
524                         *status |= FE_HAS_CARRIER;
525                 else
526                         break;
527                 i2c_read_demod_bytes(state, 0x38, buf, 1);
528                 if ((buf[0] & 0x02) == 0x00)
529                         *status |= FE_HAS_SYNC;
530                 if ((buf[0] & 0x01) == 0x01) {
531                         *status |= FE_HAS_LOCK;
532                         *status |= FE_HAS_VITERBI;
533                 }
534                 break;
535         default:
536                 printk(KERN_WARNING "lgdt330x: %s: Modulation set to unsupported value\n", __func__);
537         }
538         return 0;
539 }
540
541 /* Calculate SNR estimation (scaled by 2^24)
542
543    8-VSB SNR equations from LGDT3302 and LGDT3303 datasheets, QAM
544    equations from LGDT3303 datasheet.  VSB is the same between the '02
545    and '03, so maybe QAM is too?  Perhaps someone with a newer datasheet
546    that has QAM information could verify?
547
548    For 8-VSB: (two ways, take your pick)
549    LGDT3302:
550      SNR_EQ = 10 * log10(25 * 24^2 / EQ_MSE)
551    LGDT3303:
552      SNR_EQ = 10 * log10(25 * 32^2 / EQ_MSE)
553    LGDT3302 & LGDT3303:
554      SNR_PT = 10 * log10(25 * 32^2 / PT_MSE)  (we use this one)
555    For 64-QAM:
556      SNR    = 10 * log10( 688128   / MSEQAM)
557    For 256-QAM:
558      SNR    = 10 * log10( 696320   / MSEQAM)
559
560    We re-write the snr equation as:
561      SNR * 2^24 = 10*(c - intlog10(MSE))
562    Where for 256-QAM, c = log10(696320) * 2^24, and so on. */
563
564 static u32 calculate_snr(u32 mse, u32 c)
565 {
566         if (mse == 0) /* No signal */
567                 return 0;
568
569         mse = intlog10(mse);
570         if (mse > c) {
571                 /* Negative SNR, which is possible, but realisticly the
572                 demod will lose lock before the signal gets this bad.  The
573                 API only allows for unsigned values, so just return 0 */
574                 return 0;
575         }
576         return 10*(c - mse);
577 }
578
579 static int lgdt3302_read_snr(struct dvb_frontend* fe, u16* snr)
580 {
581         struct lgdt330x_state* state = (struct lgdt330x_state*) fe->demodulator_priv;
582         u8 buf[5];      /* read data buffer */
583         u32 noise;      /* noise value */
584         u32 c;          /* per-modulation SNR calculation constant */
585
586         switch(state->current_modulation) {
587         case VSB_8:
588                 i2c_read_demod_bytes(state, LGDT3302_EQPH_ERR0, buf, 5);
589 #ifdef USE_EQMSE
590                 /* Use Equalizer Mean-Square Error Register */
591                 /* SNR for ranges from -15.61 to +41.58 */
592                 noise = ((buf[0] & 7) << 16) | (buf[1] << 8) | buf[2];
593                 c = 69765745; /* log10(25*24^2)*2^24 */
594 #else
595                 /* Use Phase Tracker Mean-Square Error Register */
596                 /* SNR for ranges from -13.11 to +44.08 */
597                 noise = ((buf[0] & 7<<3) << 13) | (buf[3] << 8) | buf[4];
598                 c = 73957994; /* log10(25*32^2)*2^24 */
599 #endif
600                 break;
601         case QAM_64:
602         case QAM_256:
603                 i2c_read_demod_bytes(state, CARRIER_MSEQAM1, buf, 2);
604                 noise = ((buf[0] & 3) << 8) | buf[1];
605                 c = state->current_modulation == QAM_64 ? 97939837 : 98026066;
606                 /* log10(688128)*2^24 and log10(696320)*2^24 */
607                 break;
608         default:
609                 printk(KERN_ERR "lgdt330x: %s: Modulation set to unsupported value\n",
610                        __func__);
611                 return -EREMOTEIO; /* return -EDRIVER_IS_GIBBERED; */
612         }
613
614         state->snr = calculate_snr(noise, c);
615         *snr = (state->snr) >> 16; /* Convert from 8.24 fixed-point to 8.8 */
616
617         dprintk("%s: noise = 0x%08x, snr = %d.%02d dB\n", __func__, noise,
618                 state->snr >> 24, (((state->snr>>8) & 0xffff) * 100) >> 16);
619
620         return 0;
621 }
622
623 static int lgdt3303_read_snr(struct dvb_frontend* fe, u16* snr)
624 {
625         struct lgdt330x_state* state = (struct lgdt330x_state*) fe->demodulator_priv;
626         u8 buf[5];      /* read data buffer */
627         u32 noise;      /* noise value */
628         u32 c;          /* per-modulation SNR calculation constant */
629
630         switch(state->current_modulation) {
631         case VSB_8:
632                 i2c_read_demod_bytes(state, LGDT3303_EQPH_ERR0, buf, 5);
633 #ifdef USE_EQMSE
634                 /* Use Equalizer Mean-Square Error Register */
635                 /* SNR for ranges from -16.12 to +44.08 */
636                 noise = ((buf[0] & 0x78) << 13) | (buf[1] << 8) | buf[2];
637                 c = 73957994; /* log10(25*32^2)*2^24 */
638 #else
639                 /* Use Phase Tracker Mean-Square Error Register */
640                 /* SNR for ranges from -13.11 to +44.08 */
641                 noise = ((buf[0] & 7) << 16) | (buf[3] << 8) | buf[4];
642                 c = 73957994; /* log10(25*32^2)*2^24 */
643 #endif
644                 break;
645         case QAM_64:
646         case QAM_256:
647                 i2c_read_demod_bytes(state, CARRIER_MSEQAM1, buf, 2);
648                 noise = (buf[0] << 8) | buf[1];
649                 c = state->current_modulation == QAM_64 ? 97939837 : 98026066;
650                 /* log10(688128)*2^24 and log10(696320)*2^24 */
651                 break;
652         default:
653                 printk(KERN_ERR "lgdt330x: %s: Modulation set to unsupported value\n",
654                        __func__);
655                 return -EREMOTEIO; /* return -EDRIVER_IS_GIBBERED; */
656         }
657
658         state->snr = calculate_snr(noise, c);
659         *snr = (state->snr) >> 16; /* Convert from 8.24 fixed-point to 8.8 */
660
661         dprintk("%s: noise = 0x%08x, snr = %d.%02d dB\n", __func__, noise,
662                 state->snr >> 24, (((state->snr >> 8) & 0xffff) * 100) >> 16);
663
664         return 0;
665 }
666
667 static int lgdt330x_read_signal_strength(struct dvb_frontend* fe, u16* strength)
668 {
669         /* Calculate Strength from SNR up to 35dB */
670         /* Even though the SNR can go higher than 35dB, there is some comfort */
671         /* factor in having a range of strong signals that can show at 100%   */
672         struct lgdt330x_state* state = (struct lgdt330x_state*) fe->demodulator_priv;
673         u16 snr;
674         int ret;
675
676         ret = fe->ops.read_snr(fe, &snr);
677         if (ret != 0)
678                 return ret;
679         /* Rather than use the 8.8 value snr, use state->snr which is 8.24 */
680         /* scale the range 0 - 35*2^24 into 0 - 65535 */
681         if (state->snr >= 8960 * 0x10000)
682                 *strength = 0xffff;
683         else
684                 *strength = state->snr / 8960;
685
686         return 0;
687 }
688
689 static int lgdt330x_get_tune_settings(struct dvb_frontend* fe, struct dvb_frontend_tune_settings* fe_tune_settings)
690 {
691         /* I have no idea about this - it may not be needed */
692         fe_tune_settings->min_delay_ms = 500;
693         fe_tune_settings->step_size = 0;
694         fe_tune_settings->max_drift = 0;
695         return 0;
696 }
697
698 static void lgdt330x_release(struct dvb_frontend* fe)
699 {
700         struct lgdt330x_state* state = (struct lgdt330x_state*) fe->demodulator_priv;
701         kfree(state);
702 }
703
704 static struct dvb_frontend_ops lgdt3302_ops;
705 static struct dvb_frontend_ops lgdt3303_ops;
706
707 struct dvb_frontend* lgdt330x_attach(const struct lgdt330x_config* config,
708                                      struct i2c_adapter* i2c)
709 {
710         struct lgdt330x_state* state = NULL;
711         u8 buf[1];
712
713         /* Allocate memory for the internal state */
714         state = kzalloc(sizeof(struct lgdt330x_state), GFP_KERNEL);
715         if (state == NULL)
716                 goto error;
717
718         /* Setup the state */
719         state->config = config;
720         state->i2c = i2c;
721
722         /* Create dvb_frontend */
723         switch (config->demod_chip) {
724         case LGDT3302:
725                 memcpy(&state->frontend.ops, &lgdt3302_ops, sizeof(struct dvb_frontend_ops));
726                 break;
727         case LGDT3303:
728                 memcpy(&state->frontend.ops, &lgdt3303_ops, sizeof(struct dvb_frontend_ops));
729                 break;
730         default:
731                 goto error;
732         }
733         state->frontend.demodulator_priv = state;
734
735         /* Verify communication with demod chip */
736         if (i2c_read_demod_bytes(state, 2, buf, 1))
737                 goto error;
738
739         state->current_frequency = -1;
740         state->current_modulation = -1;
741
742         return &state->frontend;
743
744 error:
745         kfree(state);
746         dprintk("%s: ERROR\n",__func__);
747         return NULL;
748 }
749
750 static struct dvb_frontend_ops lgdt3302_ops = {
751         .info = {
752                 .name= "LG Electronics LGDT3302 VSB/QAM Frontend",
753                 .type = FE_ATSC,
754                 .frequency_min= 54000000,
755                 .frequency_max= 858000000,
756                 .frequency_stepsize= 62500,
757                 .symbol_rate_min    = 5056941,  /* QAM 64 */
758                 .symbol_rate_max    = 10762000, /* VSB 8  */
759                 .caps = FE_CAN_QAM_64 | FE_CAN_QAM_256 | FE_CAN_8VSB
760         },
761         .init                 = lgdt330x_init,
762         .set_frontend         = lgdt330x_set_parameters,
763         .get_frontend         = lgdt330x_get_frontend,
764         .get_tune_settings    = lgdt330x_get_tune_settings,
765         .read_status          = lgdt3302_read_status,
766         .read_ber             = lgdt330x_read_ber,
767         .read_signal_strength = lgdt330x_read_signal_strength,
768         .read_snr             = lgdt3302_read_snr,
769         .read_ucblocks        = lgdt330x_read_ucblocks,
770         .release              = lgdt330x_release,
771 };
772
773 static struct dvb_frontend_ops lgdt3303_ops = {
774         .info = {
775                 .name= "LG Electronics LGDT3303 VSB/QAM Frontend",
776                 .type = FE_ATSC,
777                 .frequency_min= 54000000,
778                 .frequency_max= 858000000,
779                 .frequency_stepsize= 62500,
780                 .symbol_rate_min    = 5056941,  /* QAM 64 */
781                 .symbol_rate_max    = 10762000, /* VSB 8  */
782                 .caps = FE_CAN_QAM_64 | FE_CAN_QAM_256 | FE_CAN_8VSB
783         },
784         .init                 = lgdt330x_init,
785         .set_frontend         = lgdt330x_set_parameters,
786         .get_frontend         = lgdt330x_get_frontend,
787         .get_tune_settings    = lgdt330x_get_tune_settings,
788         .read_status          = lgdt3303_read_status,
789         .read_ber             = lgdt330x_read_ber,
790         .read_signal_strength = lgdt330x_read_signal_strength,
791         .read_snr             = lgdt3303_read_snr,
792         .read_ucblocks        = lgdt330x_read_ucblocks,
793         .release              = lgdt330x_release,
794 };
795
796 MODULE_DESCRIPTION("LGDT330X (ATSC 8VSB & ITU-T J.83 AnnexB 64/256 QAM) Demodulator Driver");
797 MODULE_AUTHOR("Wilson Michaels");
798 MODULE_LICENSE("GPL");
799
800 EXPORT_SYMBOL(lgdt330x_attach);
801
802 /*
803  * Local variables:
804  * c-basic-offset: 8
805  * End:
806  */