summaryrefslogblamecommitdiff
path: root/sound/drivers/ml403-ac97cr.c
blob: bcca825a1c8dc6fb1fce435ba9744aa0f2c5de4e (plain) (tree)
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
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065





























                                                                               
                                                                 

                                                                                 

   
                       
                         



                                  
                       
































                                                                      
                                                       




























































































































































































































































































































































































































































































































































































































































































































































































































































































































































































































                                                                               
          











































                                                                            
          

































                                                                             

                                                                   







                                                                    
                                                     
                                                                       










                                                                
                                                     
                                                                       























                                                                            











                                                                   
          































                                                                        
          





























                                                                              
                                                                










                                                     

                                                                         

                           







































                                                                         


                 


                                                  







                                                         
                                                
/*
 * ALSA driver for Xilinx ML403 AC97 Controller Reference
 *   IP: opb_ac97_controller_ref_v1_00_a (EDK 8.1i)
 *   IP: opb_ac97_controller_ref_v1_00_a (EDK 9.1i)
 *
 *  Copyright (c) by 2007  Joachim Foerster <JOFT@gmx.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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

/* Some notes / status of this driver:
 *
 * - Don't wonder about some strange implementations of things - especially the
 * (heavy) shadowing of codec registers, with which I tried to reduce read
 * accesses to a minimum, because after a variable amount of accesses, the AC97
 * controller doesn't raise the register access finished bit anymore ...
 *
 * - Playback support seems to be pretty stable - no issues here.
 * - Capture support "works" now, too. Overruns don't happen any longer so often.
 *   But there might still be some ...
 */

#include <linux/init.h>
#include <linux/module.h>

#include <linux/platform_device.h>

#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/interrupt.h>

/* HZ */
#include <linux/param.h>
/* jiffies, time_*() */
#include <linux/jiffies.h>
/* schedule_timeout*() */
#include <linux/sched.h>
/* spin_lock*() */
#include <linux/spinlock.h>
/* struct mutex, mutex_init(), mutex_*lock() */
#include <linux/mutex.h>

/* snd_printk(), snd_printd() */
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/initval.h>
#include <sound/ac97_codec.h>

#include "pcm-indirect2.h"


#define SND_ML403_AC97CR_DRIVER "ml403-ac97cr"

MODULE_AUTHOR("Joachim Foerster <JOFT@gmx.de>");
MODULE_DESCRIPTION("Xilinx ML403 AC97 Controller Reference");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("{{Xilinx,ML403 AC97 Controller Reference}}");

static int index[SNDRV_CARDS] = SNDRV_DEFAULT_IDX;
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;
static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE;

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for ML403 AC97 Controller Reference.");
module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "ID string for ML403 AC97 Controller Reference.");
module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "Enable this ML403 AC97 Controller Reference.");

/* Special feature options */
/*#define CODEC_WRITE_CHECK_RAF*/ /* don't return after a write to a codec
				   * register, while RAF bit is not set
				   */
/* Debug options for code which may be removed completely in a final version */
#ifdef CONFIG_SND_DEBUG
/*#define CODEC_STAT*/            /* turn on some minimal "statistics"
				   * about codec register usage
				   */
#define SND_PCM_INDIRECT2_STAT    /* turn on some "statistics" about the
				   * process of copying bytes from the
				   * intermediate buffer to the hardware
				   * fifo and the other way round
				   */
#endif

/* Definition of a "level/facility dependent" printk(); may be removed
 * completely in a final version
 */
#undef PDEBUG
#ifdef CONFIG_SND_DEBUG
/* "facilities" for PDEBUG */
#define UNKNOWN       (1<<0)
#define CODEC_SUCCESS (1<<1)
#define CODEC_FAKE    (1<<2)
#define INIT_INFO     (1<<3)
#define INIT_FAILURE  (1<<4)
#define WORK_INFO     (1<<5)
#define WORK_FAILURE  (1<<6)

#define PDEBUG_FACILITIES (UNKNOWN | INIT_FAILURE | WORK_FAILURE)

#define PDEBUG(fac, fmt, args...) do { \
		if (fac & PDEBUG_FACILITIES) \
			snd_printd(KERN_DEBUG SND_ML403_AC97CR_DRIVER ": " \
				   fmt, ##args); \
	} while (0)
#else
#define PDEBUG(fac, fmt, args...) /* nothing */
#endif



/* Defines for "waits"/timeouts (portions of HZ=250 on arch/ppc by default) */
#define CODEC_TIMEOUT_ON_INIT       5	/* timeout for checking for codec
					 * readiness (after insmod)
					 */
#ifndef CODEC_WRITE_CHECK_RAF
#define CODEC_WAIT_AFTER_WRITE    100	/* general, static wait after a write
					 * access to a codec register, may be
					 * 0 to completely remove wait
					 */
#else
#define CODEC_TIMEOUT_AFTER_WRITE   5	/* timeout after a write access to a
					 * codec register, if RAF bit is used
					 */
#endif
#define CODEC_TIMEOUT_AFTER_READ    5	/* timeout after a read access to a
					 * codec register (checking RAF bit)
					 */

/* Infrastructure for codec register shadowing */
#define LM4550_REG_OK        (1<<0)   /* register exists */
#define LM4550_REG_DONEREAD  (1<<1)   /* read register once, value should be
				       * the same currently in the register
				       */
#define LM4550_REG_NOSAVE    (1<<2)   /* values written to this register will
				       * not be saved in the register
				       */
#define LM4550_REG_NOSHADOW  (1<<3)   /* don't do register shadowing, use plain
				       * hardware access
				       */
#define LM4550_REG_READONLY  (1<<4)   /* register is read only */
#define LM4550_REG_FAKEPROBE (1<<5)   /* fake write _and_ read actions during
				       * probe() correctly
				       */
#define LM4550_REG_FAKEREAD  (1<<6)   /* fake read access, always return
				       * default value
				       */
#define LM4550_REG_ALLFAKE   (LM4550_REG_FAKEREAD | LM4550_REG_FAKEPROBE)

struct lm4550_reg {
	u16 value;
	u16 flag;
	u16 wmask;
	u16 def;
};

struct lm4550_reg lm4550_regfile[64] = {
	[AC97_RESET / 2]              = {.flag = LM4550_REG_OK \
						| LM4550_REG_NOSAVE \
						| LM4550_REG_FAKEREAD,
					 .def = 0x0D50},
	[AC97_MASTER / 2]             = {.flag = LM4550_REG_OK
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x9F1F,
					 .def = 0x8000},
	[AC97_HEADPHONE / 2]          = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x9F1F,
					 .def = 0x8000},
	[AC97_MASTER_MONO / 2]        = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x801F,
					 .def = 0x8000},
	[AC97_PC_BEEP / 2]            = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x801E,
					 .def = 0x0},
	[AC97_PHONE / 2]              = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x801F,
					 .def = 0x8008},
	[AC97_MIC / 2]                = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x805F,
					 .def = 0x8008},
	[AC97_LINE / 2]               = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x9F1F,
					 .def = 0x8808},
	[AC97_CD / 2]                 = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x9F1F,
					 .def = 0x8808},
	[AC97_VIDEO / 2]              = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x9F1F,
					 .def = 0x8808},
	[AC97_AUX / 2]                = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x9F1F,
					 .def = 0x8808},
	[AC97_PCM / 2]                = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x9F1F,
					 .def = 0x8008},
	[AC97_REC_SEL / 2]            = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x707,
					 .def = 0x0},
	[AC97_REC_GAIN / 2]           = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .wmask = 0x8F0F,
					 .def = 0x8000},
	[AC97_GENERAL_PURPOSE / 2]    = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .def = 0x0,
					 .wmask = 0xA380},
	[AC97_3D_CONTROL / 2]         = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEREAD \
						| LM4550_REG_READONLY,
					 .def = 0x0101},
	[AC97_POWERDOWN / 2]          = {.flag = LM4550_REG_OK \
						| LM4550_REG_NOSHADOW \
						| LM4550_REG_NOSAVE,
					 .wmask = 0xFF00},
					/* may not write ones to
					 * REF/ANL/DAC/ADC bits
					 * FIXME: Is this ok?
					 */
	[AC97_EXTENDED_ID / 2]        = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEREAD \
						| LM4550_REG_READONLY,
					 .def = 0x0201}, /* primary codec */
	[AC97_EXTENDED_STATUS / 2]    = {.flag = LM4550_REG_OK \
						| LM4550_REG_NOSHADOW \
						| LM4550_REG_NOSAVE,
					 .wmask = 0x1},
	[AC97_PCM_FRONT_DAC_RATE / 2] = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .def = 0xBB80,
					 .wmask = 0xFFFF},
	[AC97_PCM_LR_ADC_RATE / 2]    = {.flag = LM4550_REG_OK \
						| LM4550_REG_FAKEPROBE,
					 .def = 0xBB80,
					 .wmask = 0xFFFF},
	[AC97_VENDOR_ID1 / 2]         = {.flag = LM4550_REG_OK \
						| LM4550_REG_READONLY \
						| LM4550_REG_FAKEREAD,
					 .def = 0x4E53},
	[AC97_VENDOR_ID2 / 2]         = {.flag = LM4550_REG_OK \
						| LM4550_REG_READONLY \
						| LM4550_REG_FAKEREAD,
					 .def = 0x4350}
};

#define LM4550_RF_OK(reg)    (lm4550_regfile[reg / 2].flag & LM4550_REG_OK)

static void lm4550_regfile_init(void)
{
	int i;
	for (i = 0; i < 64; i++)
		if (lm4550_regfile[i].flag & LM4550_REG_FAKEPROBE)
			lm4550_regfile[i].value = lm4550_regfile[i].def;
}

static void lm4550_regfile_write_values_after_init(struct snd_ac97 *ac97)
{
	int i;
	for (i = 0; i < 64; i++)
		if ((lm4550_regfile[i].flag & LM4550_REG_FAKEPROBE) &&
		    (lm4550_regfile[i].value != lm4550_regfile[i].def)) {
			PDEBUG(CODEC_FAKE, "lm4550_regfile_write_values_after_"
			       "init(): reg=0x%x value=0x%x / %d is different "
			       "from def=0x%x / %d\n",
			       i, lm4550_regfile[i].value,
			       lm4550_regfile[i].value, lm4550_regfile[i].def,
			       lm4550_regfile[i].def);
			snd_ac97_write(ac97, i * 2, lm4550_regfile[i].value);
			lm4550_regfile[i].flag |= LM4550_REG_DONEREAD;
		}
}


/* direct registers */
#define CR_REG(ml403_ac97cr, x) ((ml403_ac97cr)->port + CR_REG_##x)

#define CR_REG_PLAYFIFO         0x00
#define   CR_PLAYDATA(a)        ((a) & 0xFFFF)

#define CR_REG_RECFIFO          0x04
#define   CR_RECDATA(a)         ((a) & 0xFFFF)

#define CR_REG_STATUS           0x08
#define   CR_RECOVER            (1<<7)
#define   CR_PLAYUNDER          (1<<6)
#define   CR_CODECREADY         (1<<5)
#define   CR_RAF                (1<<4)
#define   CR_RECEMPTY           (1<<3)
#define   CR_RECFULL            (1<<2)
#define   CR_PLAYHALF           (1<<1)
#define   CR_PLAYFULL           (1<<0)

#define CR_REG_RESETFIFO        0x0C
#define   CR_RECRESET           (1<<1)
#define   CR_PLAYRESET          (1<<0)

#define CR_REG_CODEC_ADDR       0x10
/* UG082 says:
 * #define   CR_CODEC_ADDR(a)  ((a) << 1)
 * #define   CR_CODEC_READ     (1<<0)
 * #define   CR_CODEC_WRITE    (0<<0)
 */
/* RefDesign example says: */
#define   CR_CODEC_ADDR(a)      ((a) << 0)
#define   CR_CODEC_READ         (1<<7)
#define   CR_CODEC_WRITE        (0<<7)

#define CR_REG_CODEC_DATAREAD   0x14
#define   CR_CODEC_DATAREAD(v)  ((v) & 0xFFFF)

#define CR_REG_CODEC_DATAWRITE  0x18
#define   CR_CODEC_DATAWRITE(v) ((v) & 0xFFFF)

#define CR_FIFO_SIZE            32

struct snd_ml403_ac97cr {
	/* lock for access to (controller) registers */
	spinlock_t reg_lock;
	/* mutex for the whole sequence of accesses to (controller) registers
	 * which affect codec registers
	 */
	struct mutex cdc_mutex;

	int irq; /* for playback */
	int enable_irq;	/* for playback */

	int capture_irq;
	int enable_capture_irq;

	struct resource *res_port;
	void *port;

	struct snd_ac97 *ac97;
	int ac97_fake;
#ifdef CODEC_STAT
	int ac97_read;
	int ac97_write;
#endif

	struct platform_device *pfdev;
	struct snd_card *card;
	struct snd_pcm *pcm;
	struct snd_pcm_substream *playback_substream;
	struct snd_pcm_substream *capture_substream;

	struct snd_pcm_indirect2 ind_rec; /* for playback */
	struct snd_pcm_indirect2 capture_ind2_rec;
};

static struct snd_pcm_hardware snd_ml403_ac97cr_playback = {
	.info =	            (SNDRV_PCM_INFO_MMAP |
			     SNDRV_PCM_INFO_INTERLEAVED |
			     SNDRV_PCM_INFO_MMAP_VALID),
	.formats =          SNDRV_PCM_FMTBIT_S16_BE,
	.rates =	    (SNDRV_PCM_RATE_CONTINUOUS |
			     SNDRV_PCM_RATE_8000_48000),
	.rate_min =	    4000,
	.rate_max =	    48000,
	.channels_min =     2,
	.channels_max =     2,
	.buffer_bytes_max = (128*1024),
	.period_bytes_min = CR_FIFO_SIZE/2,
	.period_bytes_max = (64*1024),
	.periods_min =      2,
	.periods_max =      (128*1024)/(CR_FIFO_SIZE/2),
	.fifo_size =	    0,
};

static struct snd_pcm_hardware snd_ml403_ac97cr_capture = {
	.info =	            (SNDRV_PCM_INFO_MMAP |
			     SNDRV_PCM_INFO_INTERLEAVED |
			     SNDRV_PCM_INFO_MMAP_VALID),
	.formats =          SNDRV_PCM_FMTBIT_S16_BE,
	.rates =            (SNDRV_PCM_RATE_CONTINUOUS |
			     SNDRV_PCM_RATE_8000_48000),
	.rate_min =         4000,
	.rate_max =         48000,
	.channels_min =     2,
	.channels_max =     2,
	.buffer_bytes_max = (128*1024),
	.period_bytes_min = CR_FIFO_SIZE/2,
	.period_bytes_max = (64*1024),
	.periods_min =      2,
	.periods_max =      (128*1024)/(CR_FIFO_SIZE/2),
	.fifo_size =	    0,
};

static size_t
snd_ml403_ac97cr_playback_ind2_zero(struct snd_pcm_substream *substream,
				    struct snd_pcm_indirect2 *rec)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	int copied_words = 0;
	u32 full = 0;

	ml403_ac97cr = snd_pcm_substream_chip(substream);

	spin_lock(&ml403_ac97cr->reg_lock);
	while ((full = (in_be32(CR_REG(ml403_ac97cr, STATUS)) &
			CR_PLAYFULL)) != CR_PLAYFULL) {
		out_be32(CR_REG(ml403_ac97cr, PLAYFIFO), 0);
		copied_words++;
	}
	rec->hw_ready = 0;
	spin_unlock(&ml403_ac97cr->reg_lock);

	return (size_t) (copied_words * 2);
}

static size_t
snd_ml403_ac97cr_playback_ind2_copy(struct snd_pcm_substream *substream,
				    struct snd_pcm_indirect2 *rec,
				    size_t bytes)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	u16 *src;
	int copied_words = 0;
	u32 full = 0;

	ml403_ac97cr = snd_pcm_substream_chip(substream);
	src = (u16 *)(substream->runtime->dma_area + rec->sw_data);

	spin_lock(&ml403_ac97cr->reg_lock);
	while (((full = (in_be32(CR_REG(ml403_ac97cr, STATUS)) &
			 CR_PLAYFULL)) != CR_PLAYFULL) && (bytes > 1)) {
		out_be32(CR_REG(ml403_ac97cr, PLAYFIFO),
			 CR_PLAYDATA(src[copied_words]));
		copied_words++;
		bytes = bytes - 2;
	}
	if (full != CR_PLAYFULL)
		rec->hw_ready = 1;
	else
		rec->hw_ready = 0;
	spin_unlock(&ml403_ac97cr->reg_lock);

	return (size_t) (copied_words * 2);
}

static size_t
snd_ml403_ac97cr_capture_ind2_null(struct snd_pcm_substream *substream,
				   struct snd_pcm_indirect2 *rec)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	int copied_words = 0;
	u32 empty = 0;

	ml403_ac97cr = snd_pcm_substream_chip(substream);

	spin_lock(&ml403_ac97cr->reg_lock);
	while ((empty = (in_be32(CR_REG(ml403_ac97cr, STATUS)) &
			 CR_RECEMPTY)) != CR_RECEMPTY) {
		volatile u32 trash;

		trash = CR_RECDATA(in_be32(CR_REG(ml403_ac97cr, RECFIFO)));
		/* Hmmmm, really necessary? Don't want call to in_be32()
		 * to be optimised away!
		 */
		trash++;
		copied_words++;
	}
	rec->hw_ready = 0;
	spin_unlock(&ml403_ac97cr->reg_lock);

	return (size_t) (copied_words * 2);
}

static size_t
snd_ml403_ac97cr_capture_ind2_copy(struct snd_pcm_substream *substream,
				   struct snd_pcm_indirect2 *rec, size_t bytes)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	u16 *dst;
	int copied_words = 0;
	u32 empty = 0;

	ml403_ac97cr = snd_pcm_substream_chip(substream);
	dst = (u16 *)(substream->runtime->dma_area + rec->sw_data);

	spin_lock(&ml403_ac97cr->reg_lock);
	while (((empty = (in_be32(CR_REG(ml403_ac97cr, STATUS)) &
			  CR_RECEMPTY)) != CR_RECEMPTY) && (bytes > 1)) {
		dst[copied_words] = CR_RECDATA(in_be32(CR_REG(ml403_ac97cr,
							      RECFIFO)));
		copied_words++;
		bytes = bytes - 2;
	}
	if (empty != CR_RECEMPTY)
		rec->hw_ready = 1;
	else
		rec->hw_ready = 0;
	spin_unlock(&ml403_ac97cr->reg_lock);

	return (size_t) (copied_words * 2);
}

static snd_pcm_uframes_t
snd_ml403_ac97cr_pcm_pointer(struct snd_pcm_substream *substream)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	struct snd_pcm_indirect2 *ind2_rec = NULL;

	ml403_ac97cr = snd_pcm_substream_chip(substream);

	if (substream == ml403_ac97cr->playback_substream)
		ind2_rec = &ml403_ac97cr->ind_rec;
	if (substream == ml403_ac97cr->capture_substream)
		ind2_rec = &ml403_ac97cr->capture_ind2_rec;

	if (ind2_rec != NULL)
		return snd_pcm_indirect2_pointer(substream, ind2_rec);
	return (snd_pcm_uframes_t) 0;
}

static int
snd_ml403_ac97cr_pcm_playback_trigger(struct snd_pcm_substream *substream,
				      int cmd)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	int err = 0;

	ml403_ac97cr = snd_pcm_substream_chip(substream);

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
		PDEBUG(WORK_INFO, "trigger(playback): START\n");
		ml403_ac97cr->ind_rec.hw_ready = 1;

		/* clear play FIFO */
		out_be32(CR_REG(ml403_ac97cr, RESETFIFO), CR_PLAYRESET);

		/* enable play irq */
		ml403_ac97cr->enable_irq = 1;
		enable_irq(ml403_ac97cr->irq);
		break;
	case SNDRV_PCM_TRIGGER_STOP:
		PDEBUG(WORK_INFO, "trigger(playback): STOP\n");
		ml403_ac97cr->ind_rec.hw_ready = 0;
#ifdef SND_PCM_INDIRECT2_STAT
		snd_pcm_indirect2_stat(substream, &ml403_ac97cr->ind_rec);
#endif
		/* disable play irq */
		disable_irq_nosync(ml403_ac97cr->irq);
		ml403_ac97cr->enable_irq = 0;
		break;
	default:
		err = -EINVAL;
		break;
	}
	PDEBUG(WORK_INFO, "trigger(playback): (done)\n");
	return err;
}

static int
snd_ml403_ac97cr_pcm_capture_trigger(struct snd_pcm_substream *substream,
				      int cmd)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	int err = 0;

	ml403_ac97cr = snd_pcm_substream_chip(substream);

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
		PDEBUG(WORK_INFO, "trigger(capture): START\n");
		ml403_ac97cr->capture_ind2_rec.hw_ready = 0;

		/* clear record FIFO */
		out_be32(CR_REG(ml403_ac97cr, RESETFIFO), CR_RECRESET);

		/* enable record irq */
		ml403_ac97cr->enable_capture_irq = 1;
		enable_irq(ml403_ac97cr->capture_irq);
		break;
	case SNDRV_PCM_TRIGGER_STOP:
		PDEBUG(WORK_INFO, "trigger(capture): STOP\n");
		ml403_ac97cr->capture_ind2_rec.hw_ready = 0;
#ifdef SND_PCM_INDIRECT2_STAT
		snd_pcm_indirect2_stat(substream,
				       &ml403_ac97cr->capture_ind2_rec);
#endif
		/* disable capture irq */
		disable_irq_nosync(ml403_ac97cr->capture_irq);
		ml403_ac97cr->enable_capture_irq = 0;
		break;
	default:
		err = -EINVAL;
		break;
	}
	PDEBUG(WORK_INFO, "trigger(capture): (done)\n");
	return err;
}

static int
snd_ml403_ac97cr_pcm_playback_prepare(struct snd_pcm_substream *substream)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	struct snd_pcm_runtime *runtime;

	ml403_ac97cr = snd_pcm_substream_chip(substream);
	runtime = substream->runtime;

	PDEBUG(WORK_INFO,
	       "prepare(): period_bytes=%d, minperiod_bytes=%d\n",
	       snd_pcm_lib_period_bytes(substream), CR_FIFO_SIZE / 2);

	/* set sampling rate */
	snd_ac97_set_rate(ml403_ac97cr->ac97, AC97_PCM_FRONT_DAC_RATE,
			  runtime->rate);
	PDEBUG(WORK_INFO, "prepare(): rate=%d\n", runtime->rate);

	/* init struct for intermediate buffer */
	memset(&ml403_ac97cr->ind_rec, 0,
	       sizeof(struct snd_pcm_indirect2));
	ml403_ac97cr->ind_rec.hw_buffer_size = CR_FIFO_SIZE;
	ml403_ac97cr->ind_rec.sw_buffer_size =
		snd_pcm_lib_buffer_bytes(substream);
	ml403_ac97cr->ind_rec.min_periods = -1;
	ml403_ac97cr->ind_rec.min_multiple =
		snd_pcm_lib_period_bytes(substream) / (CR_FIFO_SIZE / 2);
	PDEBUG(WORK_INFO, "prepare(): hw_buffer_size=%d, "
	       "sw_buffer_size=%d, min_multiple=%d\n",
	       CR_FIFO_SIZE, ml403_ac97cr->ind_rec.sw_buffer_size,
	       ml403_ac97cr->ind_rec.min_multiple);
	return 0;
}

static int
snd_ml403_ac97cr_pcm_capture_prepare(struct snd_pcm_substream *substream)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	struct snd_pcm_runtime *runtime;

	ml403_ac97cr = snd_pcm_substream_chip(substream);
	runtime = substream->runtime;

	PDEBUG(WORK_INFO,
	       "prepare(capture): period_bytes=%d, minperiod_bytes=%d\n",
	       snd_pcm_lib_period_bytes(substream), CR_FIFO_SIZE / 2);

	/* set sampling rate */
	snd_ac97_set_rate(ml403_ac97cr->ac97, AC97_PCM_LR_ADC_RATE,
			  runtime->rate);
	PDEBUG(WORK_INFO, "prepare(capture): rate=%d\n", runtime->rate);

	/* init struct for intermediate buffer */
	memset(&ml403_ac97cr->capture_ind2_rec, 0,
	       sizeof(struct snd_pcm_indirect2));
	ml403_ac97cr->capture_ind2_rec.hw_buffer_size = CR_FIFO_SIZE;
	ml403_ac97cr->capture_ind2_rec.sw_buffer_size =
		snd_pcm_lib_buffer_bytes(substream);
	ml403_ac97cr->capture_ind2_rec.min_multiple =
		snd_pcm_lib_period_bytes(substream) / (CR_FIFO_SIZE / 2);
	PDEBUG(WORK_INFO, "prepare(capture): hw_buffer_size=%d, "
	       "sw_buffer_size=%d, min_multiple=%d\n", CR_FIFO_SIZE,
	       ml403_ac97cr->capture_ind2_rec.sw_buffer_size,
	       ml403_ac97cr->capture_ind2_rec.min_multiple);
	return 0;
}

static int snd_ml403_ac97cr_hw_free(struct snd_pcm_substream *substream)
{
	PDEBUG(WORK_INFO, "hw_free()\n");
	return snd_pcm_lib_free_pages(substream);
}

static int
snd_ml403_ac97cr_hw_params(struct snd_pcm_substream *substream,
			   struct snd_pcm_hw_params *hw_params)
{
	PDEBUG(WORK_INFO, "hw_params(): desired buffer bytes=%d, desired "
	       "period bytes=%d\n",
	       params_buffer_bytes(hw_params), params_period_bytes(hw_params));
	return snd_pcm_lib_malloc_pages(substream,
					params_buffer_bytes(hw_params));
}

static int snd_ml403_ac97cr_playback_open(struct snd_pcm_substream *substream)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	struct snd_pcm_runtime *runtime;

	ml403_ac97cr = snd_pcm_substream_chip(substream);
	runtime = substream->runtime;

	PDEBUG(WORK_INFO, "open(playback)\n");
	ml403_ac97cr->playback_substream = substream;
	runtime->hw = snd_ml403_ac97cr_playback;

	snd_pcm_hw_constraint_step(runtime, 0,
				   SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
				   CR_FIFO_SIZE / 2);
	return 0;
}

static int snd_ml403_ac97cr_capture_open(struct snd_pcm_substream *substream)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	struct snd_pcm_runtime *runtime;

	ml403_ac97cr = snd_pcm_substream_chip(substream);
	runtime = substream->runtime;

	PDEBUG(WORK_INFO, "open(capture)\n");
	ml403_ac97cr->capture_substream = substream;
	runtime->hw = snd_ml403_ac97cr_capture;

	snd_pcm_hw_constraint_step(runtime, 0,
				   SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
				   CR_FIFO_SIZE / 2);
	return 0;
}

static int snd_ml403_ac97cr_playback_close(struct snd_pcm_substream *substream)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;

	ml403_ac97cr = snd_pcm_substream_chip(substream);

	PDEBUG(WORK_INFO, "close(playback)\n");
	ml403_ac97cr->playback_substream = NULL;
	return 0;
}

static int snd_ml403_ac97cr_capture_close(struct snd_pcm_substream *substream)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;

	ml403_ac97cr = snd_pcm_substream_chip(substream);

	PDEBUG(WORK_INFO, "close(capture)\n");
	ml403_ac97cr->capture_substream = NULL;
	return 0;
}

static struct snd_pcm_ops snd_ml403_ac97cr_playback_ops = {
	.open = snd_ml403_ac97cr_playback_open,
	.close = snd_ml403_ac97cr_playback_close,
	.ioctl = snd_pcm_lib_ioctl,
	.hw_params = snd_ml403_ac97cr_hw_params,
	.hw_free = snd_ml403_ac97cr_hw_free,
	.prepare = snd_ml403_ac97cr_pcm_playback_prepare,
	.trigger = snd_ml403_ac97cr_pcm_playback_trigger,
	.pointer = snd_ml403_ac97cr_pcm_pointer,
};

static struct snd_pcm_ops snd_ml403_ac97cr_capture_ops = {
	.open = snd_ml403_ac97cr_capture_open,
	.close = snd_ml403_ac97cr_capture_close,
	.ioctl = snd_pcm_lib_ioctl,
	.hw_params = snd_ml403_ac97cr_hw_params,
	.hw_free = snd_ml403_ac97cr_hw_free,
	.prepare = snd_ml403_ac97cr_pcm_capture_prepare,
	.trigger = snd_ml403_ac97cr_pcm_capture_trigger,
	.pointer = snd_ml403_ac97cr_pcm_pointer,
};

static irqreturn_t snd_ml403_ac97cr_irq(int irq, void *dev_id)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	struct platform_device *pfdev;
	int cmp_irq;

	ml403_ac97cr = (struct snd_ml403_ac97cr *)dev_id;
	if (ml403_ac97cr == NULL)
		return IRQ_NONE;

	pfdev = ml403_ac97cr->pfdev;

	/* playback interrupt */
	cmp_irq = platform_get_irq(pfdev, 0);
	if (irq == cmp_irq) {
		if (ml403_ac97cr->enable_irq)
			snd_pcm_indirect2_playback_interrupt(
				ml403_ac97cr->playback_substream,
				&ml403_ac97cr->ind_rec,
				snd_ml403_ac97cr_playback_ind2_copy,
				snd_ml403_ac97cr_playback_ind2_zero);
		else
			goto __disable_irq;
	} else {
		/* record interrupt */
		cmp_irq = platform_get_irq(pfdev, 1);
		if (irq == cmp_irq) {
			if (ml403_ac97cr->enable_capture_irq)
				snd_pcm_indirect2_capture_interrupt(
					ml403_ac97cr->capture_substream,
					&ml403_ac97cr->capture_ind2_rec,
					snd_ml403_ac97cr_capture_ind2_copy,
					snd_ml403_ac97cr_capture_ind2_null);
			else
				goto __disable_irq;
		} else
			return IRQ_NONE;
	}
	return IRQ_HANDLED;

__disable_irq:
	PDEBUG(INIT_INFO, "irq(): irq %d is meant to be disabled! So, now try "
	       "to disable it _really_!\n", irq);
	disable_irq_nosync(irq);
	return IRQ_HANDLED;
}

static unsigned short
snd_ml403_ac97cr_codec_read(struct snd_ac97 *ac97, unsigned short reg)
{
	struct snd_ml403_ac97cr *ml403_ac97cr = ac97->private_data;
#ifdef CODEC_STAT
	u32 stat;
	u32 rafaccess = 0;
#endif
	unsigned long end_time;
	u16 value = 0;

	if (!LM4550_RF_OK(reg)) {
		snd_printk(KERN_WARNING SND_ML403_AC97CR_DRIVER ": "
			   "access to unknown/unused codec register 0x%x "
			   "ignored!\n", reg);
		return 0;
	}
	/* check if we can fake/answer this access from our shadow register */
	if ((lm4550_regfile[reg / 2].flag &
	     (LM4550_REG_DONEREAD | LM4550_REG_ALLFAKE)) &&
	    !(lm4550_regfile[reg / 2].flag & LM4550_REG_NOSHADOW)) {
		if (lm4550_regfile[reg / 2].flag & LM4550_REG_FAKEREAD) {
			PDEBUG(CODEC_FAKE, "codec_read(): faking read from "
			       "reg=0x%x, val=0x%x / %d\n",
			       reg, lm4550_regfile[reg / 2].def,
			       lm4550_regfile[reg / 2].def);
			return lm4550_regfile[reg / 2].def;
		} else if ((lm4550_regfile[reg / 2].flag &
			    LM4550_REG_FAKEPROBE) &&
			   ml403_ac97cr->ac97_fake) {
			PDEBUG(CODEC_FAKE, "codec_read(): faking read from "
			       "reg=0x%x, val=0x%x / %d (probe)\n",
			       reg, lm4550_regfile[reg / 2].value,
			       lm4550_regfile[reg / 2].value);
			return lm4550_regfile[reg / 2].value;
		} else {
#ifdef CODEC_STAT
			PDEBUG(CODEC_FAKE, "codec_read(): read access "
			       "answered by shadow register 0x%x (value=0x%x "
			       "/ %d) (cw=%d cr=%d)\n",
			       reg, lm4550_regfile[reg / 2].value,
			       lm4550_regfile[reg / 2].value,
			       ml403_ac97cr->ac97_write,
			       ml403_ac97cr->ac97_read);
#else
			PDEBUG(CODEC_FAKE, "codec_read(): read access "
			       "answered by shadow register 0x%x (value=0x%x "
			       "/ %d)\n",
			       reg, lm4550_regfile[reg / 2].value,
			       lm4550_regfile[reg / 2].value);
#endif
			return lm4550_regfile[reg / 2].value;
		}
	}
	/* if we are here, we _have_ to access the codec really, no faking */
	if (mutex_lock_interruptible(&ml403_ac97cr->cdc_mutex) != 0)
		return 0;
#ifdef CODEC_STAT
	ml403_ac97cr->ac97_read++;
#endif
	spin_lock(&ml403_ac97cr->reg_lock);
	out_be32(CR_REG(ml403_ac97cr, CODEC_ADDR),
		 CR_CODEC_ADDR(reg) | CR_CODEC_READ);
	spin_unlock(&ml403_ac97cr->reg_lock);
	end_time = jiffies + (HZ / CODEC_TIMEOUT_AFTER_READ);
	do {
		spin_lock(&ml403_ac97cr->reg_lock);
#ifdef CODEC_STAT
		rafaccess++;
		stat = in_be32(CR_REG(ml403_ac97cr, STATUS));
		if ((stat & CR_RAF) == CR_RAF) {
			value = CR_CODEC_DATAREAD(
				in_be32(CR_REG(ml403_ac97cr, CODEC_DATAREAD)));
			PDEBUG(CODEC_SUCCESS, "codec_read(): (done) reg=0x%x, "
			       "value=0x%x / %d (STATUS=0x%x)\n",
			       reg, value, value, stat);
#else
		if ((in_be32(CR_REG(ml403_ac97cr, STATUS)) &
		     CR_RAF) == CR_RAF) {
			value = CR_CODEC_DATAREAD(
				in_be32(CR_REG(ml403_ac97cr, CODEC_DATAREAD)));
			PDEBUG(CODEC_SUCCESS, "codec_read(): (done) "
			       "reg=0x%x, value=0x%x / %d\n",
			       reg, value, value);
#endif
			lm4550_regfile[reg / 2].value = value;
			lm4550_regfile[reg / 2].flag |= LM4550_REG_DONEREAD;
			spin_unlock(&ml403_ac97cr->reg_lock);
			mutex_unlock(&ml403_ac97cr->cdc_mutex);
			return value;
		}
		spin_unlock(&ml403_ac97cr->reg_lock);
		schedule_timeout_uninterruptible(1);
	} while (time_after(end_time, jiffies));
	/* read the DATAREAD register anyway, see comment below */
	spin_lock(&ml403_ac97cr->reg_lock);
	value =
	    CR_CODEC_DATAREAD(in_be32(CR_REG(ml403_ac97cr, CODEC_DATAREAD)));
	spin_unlock(&ml403_ac97cr->reg_lock);
#ifdef CODEC_STAT
	snd_printk(KERN_WARNING SND_ML403_AC97CR_DRIVER ": "
		   "timeout while codec read! "
		   "(reg=0x%x, last STATUS=0x%x, DATAREAD=0x%x / %d, %d) "
		   "(cw=%d, cr=%d)\n",
		   reg, stat, value, value, rafaccess,
		   ml403_ac97cr->ac97_write, ml403_ac97cr->ac97_read);
#else
	snd_printk(KERN_WARNING SND_ML403_AC97CR_DRIVER ": "
		   "timeout while codec read! "
		   "(reg=0x%x, DATAREAD=0x%x / %d)\n",
		   reg, value, value);
#endif
	/* BUG: This is PURE speculation! But after _most_ read timeouts the
	 * value in the register is ok!
	 */
	lm4550_regfile[reg / 2].value = value;
	lm4550_regfile[reg / 2].flag |= LM4550_REG_DONEREAD;
	mutex_unlock(&ml403_ac97cr->cdc_mutex);
	return value;
}

static void
snd_ml403_ac97cr_codec_write(struct snd_ac97 *ac97, unsigned short reg,
			     unsigned short val)
{
	struct snd_ml403_ac97cr *ml403_ac97cr = ac97->private_data;

#ifdef CODEC_STAT
	u32 stat;
	u32 rafaccess = 0;
#endif
#ifdef CODEC_WRITE_CHECK_RAF
	unsigned long end_time;
#endif

	if (!LM4550_RF_OK(reg)) {
		snd_printk(KERN_WARNING SND_ML403_AC97CR_DRIVER ": "
			   "access to unknown/unused codec register 0x%x "
			   "ignored!\n", reg);
		return;
	}
	if (lm4550_regfile[reg / 2].flag & LM4550_REG_READONLY) {
		snd_printk(KERN_WARNING SND_ML403_AC97CR_DRIVER ": "
			   "write access to read only codec register 0x%x "
			   "ignored!\n", reg);
		return;
	}
	if ((val & lm4550_regfile[reg / 2].wmask) != val) {
		snd_printk(KERN_WARNING SND_ML403_AC97CR_DRIVER ": "
			   "write access to codec register 0x%x "
			   "with bad value 0x%x / %d!\n",
			   reg, val, val);
		val = val & lm4550_regfile[reg / 2].wmask;
	}
	if (((lm4550_regfile[reg / 2].flag & LM4550_REG_FAKEPROBE) &&
	     ml403_ac97cr->ac97_fake) &&
	    !(lm4550_regfile[reg / 2].flag & LM4550_REG_NOSHADOW)) {
		PDEBUG(CODEC_FAKE, "codec_write(): faking write to reg=0x%x, "
		       "val=0x%x / %d\n", reg, val, val);
		lm4550_regfile[reg / 2].value = (val &
						lm4550_regfile[reg / 2].wmask);
		return;
	}
	if (mutex_lock_interruptible(&ml403_ac97cr->cdc_mutex) != 0)
		return;
#ifdef CODEC_STAT
	ml403_ac97cr->ac97_write++;
#endif
	spin_lock(&ml403_ac97cr->reg_lock);
	out_be32(CR_REG(ml403_ac97cr, CODEC_DATAWRITE),
		 CR_CODEC_DATAWRITE(val));
	out_be32(CR_REG(ml403_ac97cr, CODEC_ADDR),
		 CR_CODEC_ADDR(reg) | CR_CODEC_WRITE);
	spin_unlock(&ml403_ac97cr->reg_lock);
#ifdef CODEC_WRITE_CHECK_RAF
	/* check CR_CODEC_RAF bit to see if write access to register is done;
	 * loop until bit is set or timeout happens
	 */
	end_time = jiffies + HZ / CODEC_TIMEOUT_AFTER_WRITE;
	do {
		spin_lock(&ml403_ac97cr->reg_lock);
#ifdef CODEC_STAT
		rafaccess++;
		stat = in_be32(CR_REG(ml403_ac97cr, STATUS))
		if ((stat & CR_RAF) == CR_RAF) {
#else
		if ((in_be32(CR_REG(ml403_ac97cr, STATUS)) &
		     CR_RAF) == CR_RAF) {
#endif
			PDEBUG(CODEC_SUCCESS, "codec_write(): (done) "
			       "reg=0x%x, value=%d / 0x%x\n",
			       reg, val, val);
			if (!(lm4550_regfile[reg / 2].flag &
			      LM4550_REG_NOSHADOW) &&
			    !(lm4550_regfile[reg / 2].flag &
			      LM4550_REG_NOSAVE))
				lm4550_regfile[reg / 2].value = val;
			lm4550_regfile[reg / 2].flag |= LM4550_REG_DONEREAD;
			spin_unlock(&ml403_ac97cr->reg_lock);
			mutex_unlock(&ml403_ac97cr->cdc_mutex);
			return;
		}
		spin_unlock(&ml403_ac97cr->reg_lock);
		schedule_timeout_uninterruptible(1);
	} while (time_after(end_time, jiffies));
#ifdef CODEC_STAT
	snd_printk(KERN_WARNING SND_ML403_AC97CR_DRIVER ": "
		   "timeout while codec write "
		   "(reg=0x%x, val=0x%x / %d, last STATUS=0x%x, %d) "
		   "(cw=%d, cr=%d)\n",
		   reg, val, val, stat, rafaccess, ml403_ac97cr->ac97_write,
		   ml403_ac97cr->ac97_read);
#else
	snd_printk(KERN_WARNING SND_ML403_AC97CR_DRIVER ": "
		   "timeout while codec write (reg=0x%x, val=0x%x / %d)\n",
		   reg, val, val);
#endif
#else /* CODEC_WRITE_CHECK_RAF */
#if CODEC_WAIT_AFTER_WRITE > 0
	/* officially, in AC97 spec there is no possibility for a AC97
	 * controller to determine, if write access is done or not - so: How
	 * is Xilinx able to provide a RAF bit for write access?
	 * => very strange, thus just don't check RAF bit (compare with
	 * Xilinx's example app in EDK 8.1i) and wait
	 */
	schedule_timeout_uninterruptible(HZ / CODEC_WAIT_AFTER_WRITE);
#endif
	PDEBUG(CODEC_SUCCESS, "codec_write(): (done) "
	       "reg=0x%x, value=%d / 0x%x (no RAF check)\n",
	       reg, val, val);
#endif
	mutex_unlock(&ml403_ac97cr->cdc_mutex);
	return;
}

static int
snd_ml403_ac97cr_chip_init(struct snd_ml403_ac97cr *ml403_ac97cr)
{
	unsigned long end_time;
	PDEBUG(INIT_INFO, "chip_init():\n");
	end_time = jiffies + HZ / CODEC_TIMEOUT_ON_INIT;
	do {
		if (in_be32(CR_REG(ml403_ac97cr, STATUS)) & CR_CODECREADY) {
			/* clear both hardware FIFOs */
			out_be32(CR_REG(ml403_ac97cr, RESETFIFO),
				 CR_RECRESET | CR_PLAYRESET);
			PDEBUG(INIT_INFO, "chip_init(): (done)\n");
			return 0;
		}
		schedule_timeout_uninterruptible(1);
	} while (time_after(end_time, jiffies));
	snd_printk(KERN_ERR SND_ML403_AC97CR_DRIVER ": "
		   "timeout while waiting for codec, "
		   "not ready!\n");
	return -EBUSY;
}

static int snd_ml403_ac97cr_free(struct snd_ml403_ac97cr *ml403_ac97cr)
{
	PDEBUG(INIT_INFO, "free():\n");
	/* irq release */
	if (ml403_ac97cr->irq >= 0)
		free_irq(ml403_ac97cr->irq, ml403_ac97cr);
	if (ml403_ac97cr->capture_irq >= 0)
		free_irq(ml403_ac97cr->capture_irq, ml403_ac97cr);
	/* give back "port" */
	if (ml403_ac97cr->port != NULL)
		iounmap(ml403_ac97cr->port);
	kfree(ml403_ac97cr);
	PDEBUG(INIT_INFO, "free(): (done)\n");
	return 0;
}

static int snd_ml403_ac97cr_dev_free(struct snd_device *snddev)
{
	struct snd_ml403_ac97cr *ml403_ac97cr = snddev->device_data;
	PDEBUG(INIT_INFO, "dev_free():\n");
	return snd_ml403_ac97cr_free(ml403_ac97cr);
}

static int
snd_ml403_ac97cr_create(struct snd_card *card, struct platform_device *pfdev,
			struct snd_ml403_ac97cr **rml403_ac97cr)
{
	struct snd_ml403_ac97cr *ml403_ac97cr;
	int err;
	static struct snd_device_ops ops = {
		.dev_free = snd_ml403_ac97cr_dev_free,
	};
	struct resource *resource;
	int irq;

	*rml403_ac97cr = NULL;
	ml403_ac97cr = kzalloc(sizeof(*ml403_ac97cr), GFP_KERNEL);
	if (ml403_ac97cr == NULL)
		return -ENOMEM;
	spin_lock_init(&ml403_ac97cr->reg_lock);
	mutex_init(&ml403_ac97cr->cdc_mutex);
	ml403_ac97cr->card = card;
	ml403_ac97cr->pfdev = pfdev;
	ml403_ac97cr->irq = -1;
	ml403_ac97cr->enable_irq = 0;
	ml403_ac97cr->capture_irq = -1;
	ml403_ac97cr->enable_capture_irq = 0;
	ml403_ac97cr->port = NULL;
	ml403_ac97cr->res_port = NULL;

	PDEBUG(INIT_INFO, "Trying to reserve resources now ...\n");
	resource = platform_get_resource(pfdev, IORESOURCE_MEM, 0);
	/* get "port" */
	ml403_ac97cr->port = ioremap_nocache(resource->start,
					     (resource->end) -
					     (resource->start) + 1);
	if (ml403_ac97cr->port == NULL) {
		snd_printk(KERN_ERR SND_ML403_AC97CR_DRIVER ": "
			   "unable to remap memory region (%pR)\n",
			   resource);
		snd_ml403_ac97cr_free(ml403_ac97cr);
		return -EBUSY;
	}
	snd_printk(KERN_INFO SND_ML403_AC97CR_DRIVER ": "
		   "remap controller memory region to "
		   "0x%x done\n", (unsigned int)ml403_ac97cr->port);
	/* get irq */
	irq = platform_get_irq(pfdev, 0);
	if (request_irq(irq, snd_ml403_ac97cr_irq, 0,
			dev_name(&pfdev->dev), (void *)ml403_ac97cr)) {
		snd_printk(KERN_ERR SND_ML403_AC97CR_DRIVER ": "
			   "unable to grab IRQ %d\n",
			   irq);
		snd_ml403_ac97cr_free(ml403_ac97cr);
		return -EBUSY;
	}
	ml403_ac97cr->irq = irq;
	snd_printk(KERN_INFO SND_ML403_AC97CR_DRIVER ": "
		   "request (playback) irq %d done\n",
		   ml403_ac97cr->irq);
	irq = platform_get_irq(pfdev, 1);
	if (request_irq(irq, snd_ml403_ac97cr_irq, 0,
			dev_name(&pfdev->dev), (void *)ml403_ac97cr)) {
		snd_printk(KERN_ERR SND_ML403_AC97CR_DRIVER ": "
			   "unable to grab IRQ %d\n",
			   irq);
		snd_ml403_ac97cr_free(ml403_ac97cr);
		return -EBUSY;
	}
	ml403_ac97cr->capture_irq = irq;
	snd_printk(KERN_INFO SND_ML403_AC97CR_DRIVER ": "
		   "request (capture) irq %d done\n",
		   ml403_ac97cr->capture_irq);

	err = snd_ml403_ac97cr_chip_init(ml403_ac97cr);
	if (err < 0) {
		snd_ml403_ac97cr_free(ml403_ac97cr);
		return err;
	}

	err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, ml403_ac97cr, &ops);
	if (err < 0) {
		PDEBUG(INIT_FAILURE, "probe(): snd_device_new() failed!\n");
		snd_ml403_ac97cr_free(ml403_ac97cr);
		return err;
	}

	*rml403_ac97cr = ml403_ac97cr;
	return 0;
}

static void snd_ml403_ac97cr_mixer_free(struct snd_ac97 *ac97)
{
	struct snd_ml403_ac97cr *ml403_ac97cr = ac97->private_data;
	PDEBUG(INIT_INFO, "mixer_free():\n");
	ml403_ac97cr->ac97 = NULL;
	PDEBUG(INIT_INFO, "mixer_free(): (done)\n");
}

static int
snd_ml403_ac97cr_mixer(struct snd_ml403_ac97cr *ml403_ac97cr)
{
	struct snd_ac97_bus *bus;
	struct snd_ac97_template ac97;
	int err;
	static struct snd_ac97_bus_ops ops = {
		.write = snd_ml403_ac97cr_codec_write,
		.read = snd_ml403_ac97cr_codec_read,
	};
	PDEBUG(INIT_INFO, "mixer():\n");
	err = snd_ac97_bus(ml403_ac97cr->card, 0, &ops, NULL, &bus);
	if (err < 0)
		return err;

	memset(&ac97, 0, sizeof(ac97));
	ml403_ac97cr->ac97_fake = 1;
	lm4550_regfile_init();
#ifdef CODEC_STAT
	ml403_ac97cr->ac97_read = 0;
	ml403_ac97cr->ac97_write = 0;
#endif
	ac97.private_data = ml403_ac97cr;
	ac97.private_free = snd_ml403_ac97cr_mixer_free;
	ac97.scaps = AC97_SCAP_AUDIO | AC97_SCAP_SKIP_MODEM |
	    AC97_SCAP_NO_SPDIF;
	err = snd_ac97_mixer(bus, &ac97, &ml403_ac97cr->ac97);
	ml403_ac97cr->ac97_fake = 0;
	lm4550_regfile_write_values_after_init(ml403_ac97cr->ac97);
	PDEBUG(INIT_INFO, "mixer(): (done) snd_ac97_mixer()=%d\n", err);
	return err;
}

static int
snd_ml403_ac97cr_pcm(struct snd_ml403_ac97cr *ml403_ac97cr, int device,
		     struct snd_pcm **rpcm)
{
	struct snd_pcm *pcm;
	int err;

	if (rpcm)
		*rpcm = NULL;
	err = snd_pcm_new(ml403_ac97cr->card, "ML403AC97CR/1", device, 1, 1,
			  &pcm);
	if (err < 0)
		return err;
	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
			&snd_ml403_ac97cr_playback_ops);
	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
			&snd_ml403_ac97cr_capture_ops);
	pcm->private_data = ml403_ac97cr;
	pcm->info_flags = 0;
	strcpy(pcm->name, "ML403AC97CR DAC/ADC");
	ml403_ac97cr->pcm = pcm;

	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
					  snd_dma_continuous_data(GFP_KERNEL),
					  64 * 1024,
					  128 * 1024);
	if (rpcm)
		*rpcm = pcm;
	return 0;
}

static int snd_ml403_ac97cr_probe(struct platform_device *pfdev)
{
	struct snd_card *card;
	struct snd_ml403_ac97cr *ml403_ac97cr = NULL;
	int err;
	int dev = pfdev->id;

	if (dev >= SNDRV_CARDS)
		return -ENODEV;
	if (!enable[dev])
		return -ENOENT;

	err = snd_card_new(&pfdev->dev, index[dev], id[dev], THIS_MODULE,
			   0, &card);
	if (err < 0)
		return err;
	err = snd_ml403_ac97cr_create(card, pfdev, &ml403_ac97cr);
	if (err < 0) {
		PDEBUG(INIT_FAILURE, "probe(): create failed!\n");
		snd_card_free(card);
		return err;
	}
	PDEBUG(INIT_INFO, "probe(): create done\n");
	card->private_data = ml403_ac97cr;
	err = snd_ml403_ac97cr_mixer(ml403_ac97cr);
	if (err < 0) {
		snd_card_free(card);
		return err;
	}
	PDEBUG(INIT_INFO, "probe(): mixer done\n");
	err = snd_ml403_ac97cr_pcm(ml403_ac97cr, 0, NULL);
	if (err < 0) {
		snd_card_free(card);
		return err;
	}
	PDEBUG(INIT_INFO, "probe(): PCM done\n");
	strcpy(card->driver, SND_ML403_AC97CR_DRIVER);
	strcpy(card->shortname, "ML403 AC97 Controller Reference");
	sprintf(card->longname, "%s %s at 0x%lx, irq %i & %i, device %i",
		card->shortname, card->driver,
		(unsigned long)ml403_ac97cr->port, ml403_ac97cr->irq,
		ml403_ac97cr->capture_irq, dev + 1);

	err = snd_card_register(card);
	if (err < 0) {
		snd_card_free(card);
		return err;
	}
	platform_set_drvdata(pfdev, card);
	PDEBUG(INIT_INFO, "probe(): (done)\n");
	return 0;
}

static int snd_ml403_ac97cr_remove(struct platform_device *pfdev)
{
	snd_card_free(platform_get_drvdata(pfdev));
	return 0;
}

/* work with hotplug and coldplug */
MODULE_ALIAS("platform:" SND_ML403_AC97CR_DRIVER);

static struct platform_driver snd_ml403_ac97cr_driver = {
	.probe = snd_ml403_ac97cr_probe,
	.remove = snd_ml403_ac97cr_remove,
	.driver = {
		.name = SND_ML403_AC97CR_DRIVER,
	},
};

module_platform_driver(snd_ml403_ac97cr_driver);