summaryrefslogtreecommitdiffstats
path: root/sound/pci/bt87x.c
blob: 497ed6b200608e8331fb3dd42656ebe05dca6c1d (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
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
/*
 * bt87x.c - Brooktree Bt878/Bt879 driver for ALSA
 *
 * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
 *
 * based on btaudio.c by Gerd Knorr <kraxel@bytesex.org>
 *
 *
 *  This driver 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 driver 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
 */

#include <sound/driver.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/moduleparam.h>
#include <linux/bitops.h>
#include <asm/io.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/control.h>
#include <sound/initval.h>

MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
MODULE_DESCRIPTION("Brooktree Bt87x audio driver");
MODULE_LICENSE("GPL");
MODULE_SUPPORTED_DEVICE("{{Brooktree,Bt878},"
		"{Brooktree,Bt879}}");

static int index[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = -2}; /* Exclude the first card */
static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
static int enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;	/* Enable this card */
static int digital_rate[SNDRV_CARDS];	/* digital input rate */
static int load_all;	/* allow to load the non-whitelisted cards */

module_param_array(index, int, NULL, 0444);
MODULE_PARM_DESC(index, "Index value for Bt87x soundcard");
module_param_array(id, charp, NULL, 0444);
MODULE_PARM_DESC(id, "ID string for Bt87x soundcard");
module_param_array(enable, bool, NULL, 0444);
MODULE_PARM_DESC(enable, "Enable Bt87x soundcard");
module_param_array(digital_rate, int, NULL, 0444);
MODULE_PARM_DESC(digital_rate, "Digital input rate for Bt87x soundcard");
module_param(load_all, bool, 0444);
MODULE_PARM_DESC(load_all, "Allow to load the non-whitelisted cards");


/* register offsets */
#define REG_INT_STAT		0x100	/* interrupt status */
#define REG_INT_MASK		0x104	/* interrupt mask */
#define REG_GPIO_DMA_CTL	0x10c	/* audio control */
#define REG_PACKET_LEN		0x110	/* audio packet lengths */
#define REG_RISC_STRT_ADD	0x114	/* RISC program start address */
#define REG_RISC_COUNT		0x120	/* RISC program counter */

/* interrupt bits */
#define INT_OFLOW	(1 <<  3)	/* audio A/D overflow */
#define INT_RISCI	(1 << 11)	/* RISC instruction IRQ bit set */
#define INT_FBUS	(1 << 12)	/* FIFO overrun due to bus access latency */
#define INT_FTRGT	(1 << 13)	/* FIFO overrun due to target latency */
#define INT_FDSR	(1 << 14)	/* FIFO data stream resynchronization */
#define INT_PPERR	(1 << 15)	/* PCI parity error */
#define INT_RIPERR	(1 << 16)	/* RISC instruction parity error */
#define INT_PABORT	(1 << 17)	/* PCI master or target abort */
#define INT_OCERR	(1 << 18)	/* invalid opcode */
#define INT_SCERR	(1 << 19)	/* sync counter overflow */
#define INT_RISC_EN	(1 << 27)	/* DMA controller running */
#define INT_RISCS_SHIFT	      28	/* RISC status bits */

/* audio control bits */
#define CTL_FIFO_ENABLE		(1 <<  0)	/* enable audio data FIFO */
#define CTL_RISC_ENABLE		(1 <<  1)	/* enable audio DMA controller */
#define CTL_PKTP_4		(0 <<  2)	/* packet mode FIFO trigger point - 4 DWORDs */
#define CTL_PKTP_8		(1 <<  2)	/* 8 DWORDs */
#define CTL_PKTP_16		(2 <<  2)	/* 16 DWORDs */
#define CTL_ACAP_EN		(1 <<  4)	/* enable audio capture */
#define CTL_DA_APP		(1 <<  5)	/* GPIO input */
#define CTL_DA_IOM_AFE		(0 <<  6)	/* audio A/D input */
#define CTL_DA_IOM_DA		(1 <<  6)	/* digital audio input */
#define CTL_DA_SDR_SHIFT	       8	/* DDF first stage decimation rate */
#define CTL_DA_SDR_MASK		(0xf<< 8)
#define CTL_DA_LMT		(1 << 12)	/* limit audio data values */
#define CTL_DA_ES2		(1 << 13)	/* enable DDF stage 2 */
#define CTL_DA_SBR		(1 << 14)	/* samples rounded to 8 bits */
#define CTL_DA_DPM		(1 << 15)	/* data packet mode */
#define CTL_DA_LRD_SHIFT	      16	/* ALRCK delay */
#define CTL_DA_MLB		(1 << 21)	/* MSB/LSB format */
#define CTL_DA_LRI		(1 << 22)	/* left/right indication */
#define CTL_DA_SCE		(1 << 23)	/* sample clock edge */
#define CTL_A_SEL_STV		(0 << 24)	/* TV tuner audio input */
#define CTL_A_SEL_SFM		(1 << 24)	/* FM audio input */
#define CTL_A_SEL_SML		(2 << 24)	/* mic/line audio input */
#define CTL_A_SEL_SMXC		(3 << 24)	/* MUX bypass */
#define CTL_A_SEL_SHIFT		      24
#define CTL_A_SEL_MASK		(3 << 24)
#define CTL_A_PWRDN		(1 << 26)	/* analog audio power-down */
#define CTL_A_G2X		(1 << 27)	/* audio gain boost */
#define CTL_A_GAIN_SHIFT	      28	/* audio input gain */
#define CTL_A_GAIN_MASK		(0xf<<28)

/* RISC instruction opcodes */
#define RISC_WRITE	(0x1 << 28)	/* write FIFO data to memory at address */
#define RISC_WRITEC	(0x5 << 28)	/* write FIFO data to memory at current address */
#define RISC_SKIP	(0x2 << 28)	/* skip FIFO data */
#define RISC_JUMP	(0x7 << 28)	/* jump to address */
#define RISC_SYNC	(0x8 << 28)	/* synchronize with FIFO */

/* RISC instruction bits */
#define RISC_BYTES_ENABLE	(0xf << 12)	/* byte enable bits */
#define RISC_RESYNC		(  1 << 15)	/* disable FDSR errors */
#define RISC_SET_STATUS_SHIFT	        16	/* set status bits */
#define RISC_RESET_STATUS_SHIFT	        20	/* clear status bits */
#define RISC_IRQ		(  1 << 24)	/* interrupt */
#define RISC_EOL		(  1 << 26)	/* end of line */
#define RISC_SOL		(  1 << 27)	/* start of line */

/* SYNC status bits values */
#define RISC_SYNC_FM1	0x6
#define RISC_SYNC_VRO	0xc

#define ANALOG_CLOCK 1792000
#ifdef CONFIG_SND_BT87X_OVERCLOCK
#define CLOCK_DIV_MIN 1
#else
#define CLOCK_DIV_MIN 4
#endif
#define CLOCK_DIV_MAX 15

#define ERROR_INTERRUPTS (INT_FBUS | INT_FTRGT | INT_PPERR | \
			  INT_RIPERR | INT_PABORT | INT_OCERR)
#define MY_INTERRUPTS (INT_RISCI | ERROR_INTERRUPTS)

/* SYNC, one WRITE per line, one extra WRITE per page boundary, SYNC, JUMP */
#define MAX_RISC_SIZE ((1 + 255 + (PAGE_ALIGN(255 * 4092) / PAGE_SIZE - 1) + 1 + 1) * 8)

struct snd_bt87x {
	struct snd_card *card;
	struct pci_dev *pci;

	void __iomem *mmio;
	int irq;

	int dig_rate;

	spinlock_t reg_lock;
	long opened;
	struct snd_pcm_substream *substream;

	struct snd_dma_buffer dma_risc;
	unsigned int line_bytes;
	unsigned int lines;

	u32 reg_control;
	u32 interrupt_mask;

	int current_line;

	int pci_parity_errors;
};

enum { DEVICE_DIGITAL, DEVICE_ANALOG };

static inline u32 snd_bt87x_readl(struct snd_bt87x *chip, u32 reg)
{
	return readl(chip->mmio + reg);
}

static inline void snd_bt87x_writel(struct snd_bt87x *chip, u32 reg, u32 value)
{
	writel(value, chip->mmio + reg);
}

static int snd_bt87x_create_risc(struct snd_bt87x *chip, struct snd_pcm_substream *substream,
			       	 unsigned int periods, unsigned int period_bytes)
{
	struct snd_sg_buf *sgbuf = snd_pcm_substream_sgbuf(substream);
	unsigned int i, offset;
	u32 *risc;

	if (chip->dma_risc.area == NULL) {
		if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(chip->pci),
					PAGE_ALIGN(MAX_RISC_SIZE), &chip->dma_risc) < 0)
			return -ENOMEM;
	}
	risc = (u32 *)chip->dma_risc.area;
	offset = 0;
	*risc++ = cpu_to_le32(RISC_SYNC | RISC_SYNC_FM1);
	*risc++ = cpu_to_le32(0);
	for (i = 0; i < periods; ++i) {
		u32 rest;

		rest = period_bytes;
		do {
			u32 cmd, len;

			len = PAGE_SIZE - (offset % PAGE_SIZE);
			if (len > rest)
				len = rest;
			cmd = RISC_WRITE | len;
			if (rest == period_bytes) {
				u32 block = i * 16 / periods;
				cmd |= RISC_SOL;
				cmd |= block << RISC_SET_STATUS_SHIFT;
				cmd |= (~block & 0xf) << RISC_RESET_STATUS_SHIFT;
			}
			if (len == rest)
				cmd |= RISC_EOL | RISC_IRQ;
			*risc++ = cpu_to_le32(cmd);
			*risc++ = cpu_to_le32((u32)snd_pcm_sgbuf_get_addr(sgbuf, offset));
			offset += len;
			rest -= len;
		} while (rest > 0);
	}
	*risc++ = cpu_to_le32(RISC_SYNC | RISC_SYNC_VRO);
	*risc++ = cpu_to_le32(0);
	*risc++ = cpu_to_le32(RISC_JUMP);
	*risc++ = cpu_to_le32(chip->dma_risc.addr);
	chip->line_bytes = period_bytes;
	chip->lines = periods;
	return 0;
}

static void snd_bt87x_free_risc(struct snd_bt87x *chip)
{
	if (chip->dma_risc.area) {
		snd_dma_free_pages(&chip->dma_risc);
		chip->dma_risc.area = NULL;
	}
}

static void snd_bt87x_pci_error(struct snd_bt87x *chip, unsigned int status)
{
	u16 pci_status;

	pci_read_config_word(chip->pci, PCI_STATUS, &pci_status);
	pci_status &= PCI_STATUS_PARITY | PCI_STATUS_SIG_TARGET_ABORT |
		PCI_STATUS_REC_TARGET_ABORT | PCI_STATUS_REC_MASTER_ABORT |
		PCI_STATUS_SIG_SYSTEM_ERROR | PCI_STATUS_DETECTED_PARITY;
	pci_write_config_word(chip->pci, PCI_STATUS, pci_status);
	if (pci_status != PCI_STATUS_DETECTED_PARITY)
		snd_printk(KERN_ERR "Aieee - PCI error! status %#08x, PCI status %#04x\n",
			   status & ERROR_INTERRUPTS, pci_status);
	else {
		snd_printk(KERN_ERR "Aieee - PCI parity error detected!\n");
		/* error 'handling' similar to aic7xxx_pci.c: */
		chip->pci_parity_errors++;
		if (chip->pci_parity_errors > 20) {
			snd_printk(KERN_ERR "Too many PCI parity errors observed.\n");
			snd_printk(KERN_ERR "Some device on this bus is generating bad parity.\n");
			snd_printk(KERN_ERR "This is an error *observed by*, not *generated by*, this card.\n");
			snd_printk(KERN_ERR "PCI parity error checking has been disabled.\n");
			chip->interrupt_mask &= ~(INT_PPERR | INT_RIPERR);
			snd_bt87x_writel(chip, REG_INT_MASK, chip->interrupt_mask);
		}
	}
}

static irqreturn_t snd_bt87x_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	struct snd_bt87x *chip = dev_id;
	unsigned int status, irq_status;

	status = snd_bt87x_readl(chip, REG_INT_STAT);
	irq_status = status & chip->interrupt_mask;
	if (!irq_status)
		return IRQ_NONE;
	snd_bt87x_writel(chip, REG_INT_STAT, irq_status);

	if (irq_status & ERROR_INTERRUPTS) {
		if (irq_status & (INT_FBUS | INT_FTRGT))
			snd_printk(KERN_WARNING "FIFO overrun, status %#08x\n", status);
		if (irq_status & INT_OCERR)
			snd_printk(KERN_ERR "internal RISC error, status %#08x\n", status);
		if (irq_status & (INT_PPERR | INT_RIPERR | INT_PABORT))
			snd_bt87x_pci_error(chip, irq_status);
	}
	if ((irq_status & INT_RISCI) && (chip->reg_control & CTL_ACAP_EN)) {
		int current_block, irq_block;

		/* assume that exactly one line has been recorded */
		chip->current_line = (chip->current_line + 1) % chip->lines;
		/* but check if some interrupts have been skipped */
		current_block = chip->current_line * 16 / chip->lines;
		irq_block = status >> INT_RISCS_SHIFT;
		if (current_block != irq_block)
			chip->current_line = (irq_block * chip->lines + 15) / 16;

		snd_pcm_period_elapsed(chip->substream);
	}
	return IRQ_HANDLED;
}

static struct snd_pcm_hardware snd_bt87x_digital_hw = {
	.info = SNDRV_PCM_INFO_MMAP |
		SNDRV_PCM_INFO_INTERLEAVED |
		SNDRV_PCM_INFO_BLOCK_TRANSFER |
		SNDRV_PCM_INFO_MMAP_VALID,
	.formats = SNDRV_PCM_FMTBIT_S16_LE,
	.rates = 0, /* set at runtime */
	.channels_min = 2,
	.channels_max = 2,
	.buffer_bytes_max = 255 * 4092,
	.period_bytes_min = 32,
	.period_bytes_max = 4092,
	.periods_min = 2,
	.periods_max = 255,
};

static struct snd_pcm_hardware snd_bt87x_analog_hw = {
	.info = SNDRV_PCM_INFO_MMAP |
		SNDRV_PCM_INFO_INTERLEAVED |
		SNDRV_PCM_INFO_BLOCK_TRANSFER |
		SNDRV_PCM_INFO_MMAP_VALID,
	.formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S8,
	.rates = SNDRV_PCM_RATE_KNOT,
	.rate_min = ANALOG_CLOCK / CLOCK_DIV_MAX,
	.rate_max = ANALOG_CLOCK / CLOCK_DIV_MIN,
	.channels_min = 1,
	.channels_max = 1,
	.buffer_bytes_max = 255 * 4092,
	.period_bytes_min = 32,
	.period_bytes_max = 4092,
	.periods_min = 2,
	.periods_max = 255,
};

static int snd_bt87x_set_digital_hw(struct snd_bt87x *chip, struct snd_pcm_runtime *runtime)
{
	static struct {
		int rate;
		unsigned int bit;
	} ratebits[] = {
		{8000, SNDRV_PCM_RATE_8000},
		{11025, SNDRV_PCM_RATE_11025},
		{16000, SNDRV_PCM_RATE_16000},
		{22050, SNDRV_PCM_RATE_22050},
		{32000, SNDRV_PCM_RATE_32000},
		{44100, SNDRV_PCM_RATE_44100},
		{48000, SNDRV_PCM_RATE_48000}
	};
	int i;

	chip->reg_control |= CTL_DA_IOM_DA;
	runtime->hw = snd_bt87x_digital_hw;
	runtime->hw.rates = SNDRV_PCM_RATE_KNOT;
	for (i = 0; i < ARRAY_SIZE(ratebits); ++i)
		if (chip->dig_rate == ratebits[i].rate) {
			runtime->hw.rates = ratebits[i].bit;
			break;
		}
	runtime->hw.rate_min = chip->dig_rate;
	runtime->hw.rate_max = chip->dig_rate;
	return 0;
}

static int snd_bt87x_set_analog_hw(struct snd_bt87x *chip, struct snd_pcm_runtime *runtime)
{
	static struct snd_ratnum analog_clock = {
		.num = ANALOG_CLOCK,
		.den_min = CLOCK_DIV_MIN,
		.den_max = CLOCK_DIV_MAX,
		.den_step = 1
	};
	static struct snd_pcm_hw_constraint_ratnums constraint_rates = {
		.nrats = 1,
		.rats = &analog_clock
	};

	chip->reg_control &= ~CTL_DA_IOM_DA;
	runtime->hw = snd_bt87x_analog_hw;
	return snd_pcm_hw_constraint_ratnums(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
					     &constraint_rates);
}

static int snd_bt87x_pcm_open(struct snd_pcm_substream *substream)
{
	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	int err;

	if (test_and_set_bit(0, &chip->opened))
		return -EBUSY;

	if (substream->pcm->device == DEVICE_DIGITAL)
		err = snd_bt87x_set_digital_hw(chip, runtime);
	else
		err = snd_bt87x_set_analog_hw(chip, runtime);
	if (err < 0)
		goto _error;

	err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
	if (err < 0)
		goto _error;

	chip->substream = substream;
	return 0;

_error:
	clear_bit(0, &chip->opened);
	smp_mb__after_clear_bit();
	return err;
}

static int snd_bt87x_close(struct snd_pcm_substream *substream)
{
	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);

	chip->substream = NULL;
	clear_bit(0, &chip->opened);
	smp_mb__after_clear_bit();
	return 0;
}

static int snd_bt87x_hw_params(struct snd_pcm_substream *substream,
			       struct snd_pcm_hw_params *hw_params)
{
	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);
	int err;

	err = snd_pcm_lib_malloc_pages(substream,
				       params_buffer_bytes(hw_params));
	if (err < 0)
		return err;
	return snd_bt87x_create_risc(chip, substream,
				     params_periods(hw_params),
				     params_period_bytes(hw_params));
}

static int snd_bt87x_hw_free(struct snd_pcm_substream *substream)
{
	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);

	snd_bt87x_free_risc(chip);
	snd_pcm_lib_free_pages(substream);
	return 0;
}

static int snd_bt87x_prepare(struct snd_pcm_substream *substream)
{
	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;
	int decimation;

	spin_lock_irq(&chip->reg_lock);
	chip->reg_control &= ~(CTL_DA_SDR_MASK | CTL_DA_SBR);
	decimation = (ANALOG_CLOCK + runtime->rate / 4) / runtime->rate;
	chip->reg_control |= decimation << CTL_DA_SDR_SHIFT;
	if (runtime->format == SNDRV_PCM_FORMAT_S8)
		chip->reg_control |= CTL_DA_SBR;
	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
	spin_unlock_irq(&chip->reg_lock);
	return 0;
}

static int snd_bt87x_start(struct snd_bt87x *chip)
{
	spin_lock(&chip->reg_lock);
	chip->current_line = 0;
	chip->reg_control |= CTL_FIFO_ENABLE | CTL_RISC_ENABLE | CTL_ACAP_EN;
	snd_bt87x_writel(chip, REG_RISC_STRT_ADD, chip->dma_risc.addr);
	snd_bt87x_writel(chip, REG_PACKET_LEN,
			 chip->line_bytes | (chip->lines << 16));
	snd_bt87x_writel(chip, REG_INT_MASK, chip->interrupt_mask);
	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
	spin_unlock(&chip->reg_lock);
	return 0;
}

static int snd_bt87x_stop(struct snd_bt87x *chip)
{
	spin_lock(&chip->reg_lock);
	chip->reg_control &= ~(CTL_FIFO_ENABLE | CTL_RISC_ENABLE | CTL_ACAP_EN);
	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
	snd_bt87x_writel(chip, REG_INT_MASK, 0);
	snd_bt87x_writel(chip, REG_INT_STAT, MY_INTERRUPTS);
	spin_unlock(&chip->reg_lock);
	return 0;
}

static int snd_bt87x_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
		return snd_bt87x_start(chip);
	case SNDRV_PCM_TRIGGER_STOP:
		return snd_bt87x_stop(chip);
	default:
		return -EINVAL;
	}
}

static snd_pcm_uframes_t snd_bt87x_pointer(struct snd_pcm_substream *substream)
{
	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);
	struct snd_pcm_runtime *runtime = substream->runtime;

	return (snd_pcm_uframes_t)bytes_to_frames(runtime, chip->current_line * chip->line_bytes);
}

static struct snd_pcm_ops snd_bt87x_pcm_ops = {
	.open = snd_bt87x_pcm_open,
	.close = snd_bt87x_close,
	.ioctl = snd_pcm_lib_ioctl,
	.hw_params = snd_bt87x_hw_params,
	.hw_free = snd_bt87x_hw_free,
	.prepare = snd_bt87x_prepare,
	.trigger = snd_bt87x_trigger,
	.pointer = snd_bt87x_pointer,
	.page = snd_pcm_sgbuf_ops_page,
};

static int snd_bt87x_capture_volume_info(struct snd_kcontrol *kcontrol,
					 struct snd_ctl_elem_info *info)
{
	info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
	info->count = 1;
	info->value.integer.min = 0;
	info->value.integer.max = 15;
	return 0;
}

static int snd_bt87x_capture_volume_get(struct snd_kcontrol *kcontrol,
					struct snd_ctl_elem_value *value)
{
	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);

	value->value.integer.value[0] = (chip->reg_control & CTL_A_GAIN_MASK) >> CTL_A_GAIN_SHIFT;
	return 0;
}

static int snd_bt87x_capture_volume_put(struct snd_kcontrol *kcontrol,
					struct snd_ctl_elem_value *value)
{
	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);
	u32 old_control;
	int changed;

	spin_lock_irq(&chip->reg_lock);
	old_control = chip->reg_control;
	chip->reg_control = (chip->reg_control & ~CTL_A_GAIN_MASK)
		| (value->value.integer.value[0] << CTL_A_GAIN_SHIFT);
	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
	changed = old_control != chip->reg_control;
	spin_unlock_irq(&chip->reg_lock);
	return changed;
}

static struct snd_kcontrol_new snd_bt87x_capture_volume = {
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Capture Volume",
	.info = snd_bt87x_capture_volume_info,
	.get = snd_bt87x_capture_volume_get,
	.put = snd_bt87x_capture_volume_put,
};

static int snd_bt87x_capture_boost_info(struct snd_kcontrol *kcontrol,
					struct snd_ctl_elem_info *info)
{
	info->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN;
	info->count = 1;
	info->value.integer.min = 0;
	info->value.integer.max = 1;
	return 0;
}

static int snd_bt87x_capture_boost_get(struct snd_kcontrol *kcontrol,
				       struct snd_ctl_elem_value *value)
{
	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);

	value->value.integer.value[0] = !! (chip->reg_control & CTL_A_G2X);
	return 0;
}

static int snd_bt87x_capture_boost_put(struct snd_kcontrol *kcontrol,
				       struct snd_ctl_elem_value *value)
{
	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);
	u32 old_control;
	int changed;

	spin_lock_irq(&chip->reg_lock);
	old_control = chip->reg_control;
	chip->reg_control = (chip->reg_control & ~CTL_A_G2X)
		| (value->value.integer.value[0] ? CTL_A_G2X : 0);
	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
	changed = chip->reg_control != old_control;
	spin_unlock_irq(&chip->reg_lock);
	return changed;
}

static struct snd_kcontrol_new snd_bt87x_capture_boost = {
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Capture Boost",
	.info = snd_bt87x_capture_boost_info,
	.get = snd_bt87x_capture_boost_get,
	.put = snd_bt87x_capture_boost_put,
};

static int snd_bt87x_capture_source_info(struct snd_kcontrol *kcontrol,
					 struct snd_ctl_elem_info *info)
{
	static char *texts[3] = {"TV Tuner", "FM", "Mic/Line"};

	info->type = SNDRV_CTL_ELEM_TYPE_ENUMERATED;
	info->count = 1;
	info->value.enumerated.items = 3;
	if (info->value.enumerated.item > 2)
		info->value.enumerated.item = 2;
	strcpy(info->value.enumerated.name, texts[info->value.enumerated.item]);
	return 0;
}

static int snd_bt87x_capture_source_get(struct snd_kcontrol *kcontrol,
					struct snd_ctl_elem_value *value)
{
	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);

	value->value.enumerated.item[0] = (chip->reg_control & CTL_A_SEL_MASK) >> CTL_A_SEL_SHIFT;
	return 0;
}

static int snd_bt87x_capture_source_put(struct snd_kcontrol *kcontrol,
					struct snd_ctl_elem_value *value)
{
	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);
	u32 old_control;
	int changed;

	spin_lock_irq(&chip->reg_lock);
	old_control = chip->reg_control;
	chip->reg_control = (chip->reg_control & ~CTL_A_SEL_MASK)
		| (value->value.enumerated.item[0] << CTL_A_SEL_SHIFT);
	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
	changed = chip->reg_control != old_control;
	spin_unlock_irq(&chip->reg_lock);
	return changed;
}

static struct snd_kcontrol_new snd_bt87x_capture_source = {
	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
	.name = "Capture Source",
	.info = snd_bt87x_capture_source_info,
	.get = snd_bt87x_capture_source_get,
	.put = snd_bt87x_capture_source_put,
};

static int snd_bt87x_free(struct snd_bt87x *chip)
{
	if (chip->mmio) {
		snd_bt87x_stop(chip);
		if (chip->irq >= 0)
			synchronize_irq(chip->irq);

		iounmap(chip->mmio);
	}
	if (chip->irq >= 0)
		free_irq(chip->irq, chip);
	pci_release_regions(chip->pci);
	pci_disable_device(chip->pci);
	kfree(chip);
	return 0;
}

static int snd_bt87x_dev_free(struct snd_device *device)
{
	struct snd_bt87x *chip = device->device_data;
	return snd_bt87x_free(chip);
}

static int __devinit snd_bt87x_pcm(struct snd_bt87x *chip, int device, char *name)
{
	int err;
	struct snd_pcm *pcm;

	err = snd_pcm_new(chip->card, name, device, 0, 1, &pcm);
	if (err < 0)
		return err;
	pcm->private_data = chip;
	strcpy(pcm->name, name);
	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_bt87x_pcm_ops);
	return snd_pcm_lib_preallocate_pages_for_all(pcm,
						     SNDRV_DMA_TYPE_DEV_SG,
						     snd_dma_pci_data(chip->pci),
							128 * 1024,
							(255 * 4092 + 1023) & ~1023);
}

static int __devinit snd_bt87x_create(struct snd_card *card,
				      struct pci_dev *pci,
				      struct snd_bt87x **rchip)
{
	struct snd_bt87x *chip;
	int err;
	static struct snd_device_ops ops = {
		.dev_free = snd_bt87x_dev_free
	};

	*rchip = NULL;

	err = pci_enable_device(pci);
	if (err < 0)
		return err;

	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
	if (!chip) {
		pci_disable_device(pci);
		return -ENOMEM;
	}
	chip->card = card;
	chip->pci = pci;
	chip->irq = -1;
	spin_lock_init(&chip->reg_lock);

	if ((err = pci_request_regions(pci, "Bt87x audio")) < 0) {
		kfree(chip);
		pci_disable_device(pci);
		return err;
	}
	chip->mmio = ioremap_nocache(pci_resource_start(pci, 0),
				     pci_resource_len(pci, 0));
	if (!chip->mmio) {
		snd_bt87x_free(chip);
		snd_printk(KERN_ERR "cannot remap io memory\n");
		return -ENOMEM;
	}

	chip->reg_control = CTL_DA_ES2 | CTL_PKTP_16 | (15 << CTL_DA_SDR_SHIFT);
	chip->interrupt_mask = MY_INTERRUPTS;
	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
	snd_bt87x_writel(chip, REG_INT_MASK, 0);
	snd_bt87x_writel(chip, REG_INT_STAT, MY_INTERRUPTS);

	if (request_irq(pci->irq, snd_bt87x_interrupt, SA_INTERRUPT | SA_SHIRQ,
			"Bt87x audio", chip)) {
		snd_bt87x_free(chip);
		snd_printk(KERN_ERR "cannot grab irq\n");
		return -EBUSY;
	}
	chip->irq = pci->irq;
	pci_set_master(pci);
	synchronize_irq(chip->irq);

	err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
	if (err < 0) {
		snd_bt87x_free(chip);
		return err;
	}
	snd_card_set_dev(card, &pci->dev);
	*rchip = chip;
	return 0;
}

#define BT_DEVICE(chip, subvend, subdev, rate) \
	{ .vendor = PCI_VENDOR_ID_BROOKTREE, \
	  .device = chip, \
	  .subvendor = subvend, .subdevice = subdev, \
	  .driver_data = rate }

/* driver_data is the default digital_rate value for that device */
static struct pci_device_id snd_bt87x_ids[] __devinitdata = {
	/* Hauppauge WinTV series */
	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x0070, 0x13eb, 32000),
	/* Hauppauge WinTV series */
	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_879, 0x0070, 0x13eb, 32000),
	/* Viewcast Osprey 200 */
	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x0070, 0xff01, 44100),
	/* Leadtek Winfast tv 2000xp delux */
	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x107d, 0x6606, 32000),
	/* Voodoo TV 200 */
	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x121a, 0x3000, 32000),
	/* AVerMedia Studio No. 103, 203, ...? */
	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x1461, 0x0003, 48000),
	{ }
};
MODULE_DEVICE_TABLE(pci, snd_bt87x_ids);

/* cards known not to have audio
 * (DVB cards use the audio function to transfer MPEG data) */
static struct {
	unsigned short subvendor, subdevice;
} blacklist[] __devinitdata = {
	{0x0071, 0x0101}, /* Nebula Electronics DigiTV */
	{0x11bd, 0x001c}, /* Pinnacle PCTV Sat */
	{0x11bd, 0x0026}, /* Pinnacle PCTV SAT CI */
	{0x1461, 0x0761}, /* AVermedia AverTV DVB-T */
	{0x1461, 0x0771}, /* AVermedia DVB-T 771 */
	{0x1822, 0x0001}, /* Twinhan VisionPlus DVB-T */
	{0x18ac, 0xd500}, /* DVICO FusionHDTV 5 Lite */
	{0x18ac, 0xdb10}, /* DVICO FusionHDTV DVB-T Lite */
	{0x270f, 0xfc00}, /* Chaintech Digitop DST-1000 DVB-S */
	{0x7063, 0x2000}, /* pcHDTV HD-2000 TV */
};

static struct pci_driver driver;

/* return the rate of the card, or a negative value if it's blacklisted */
static int __devinit snd_bt87x_detect_card(struct pci_dev *pci)
{
	int i;
	const struct pci_device_id *supported;

	supported = pci_match_device(&driver, pci);
	if (supported && supported->driver_data > 0)
		return supported->driver_data;

	for (i = 0; i < ARRAY_SIZE(blacklist); ++i)
		if (blacklist[i].subvendor == pci->subsystem_vendor &&
		    blacklist[i].subdevice == pci->subsystem_device) {
			snd_printdd(KERN_INFO "card %#04x-%#04x:%#04x has no audio\n",
				    pci->device, pci->subsystem_vendor, pci->subsystem_device);
			return -EBUSY;
		}

	snd_printk(KERN_INFO "unknown card %#04x-%#04x:%#04x, using default rate 32000\n",
	           pci->device, pci->subsystem_vendor, pci->subsystem_device);
	snd_printk(KERN_DEBUG "please mail id, board name, and, "
		   "if it works, the correct digital_rate option to "
		   "<alsa-devel@lists.sf.net>\n");
	return 32000; /* default rate */
}

static int __devinit snd_bt87x_probe(struct pci_dev *pci,
				     const struct pci_device_id *pci_id)
{
	static int dev;
	struct snd_card *card;
	struct snd_bt87x *chip;
	int err, rate;

	rate = pci_id->driver_data;
	if (! rate)
		if ((rate = snd_bt87x_detect_card(pci)) <= 0)
			return -ENODEV;

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

	card = snd_card_new(index[dev], id[dev], THIS_MODULE, 0);
	if (!card)
		return -ENOMEM;

	err = snd_bt87x_create(card, pci, &chip);
	if (err < 0)
		goto _error;

	if (digital_rate[dev] > 0)
		chip->dig_rate = digital_rate[dev];
	else
		chip->dig_rate = rate;

	err = snd_bt87x_pcm(chip, DEVICE_DIGITAL, "Bt87x Digital");
	if (err < 0)
		goto _error;
	err = snd_bt87x_pcm(chip, DEVICE_ANALOG, "Bt87x Analog");
	if (err < 0)
		goto _error;

	err = snd_ctl_add(card, snd_ctl_new1(&snd_bt87x_capture_volume, chip));
	if (err < 0)
		goto _error;
	err = snd_ctl_add(card, snd_ctl_new1(&snd_bt87x_capture_boost, chip));
	if (err < 0)
		goto _error;
	err = snd_ctl_add(card, snd_ctl_new1(&snd_bt87x_capture_source, chip));
	if (err < 0)
		goto _error;

	strcpy(card->driver, "Bt87x");
	sprintf(card->shortname, "Brooktree Bt%x", pci->device);
	sprintf(card->longname, "%s at %#llx, irq %i",
		card->shortname, (unsigned long long)pci_resource_start(pci, 0),
		chip->irq);
	strcpy(card->mixername, "Bt87x");

	err = snd_card_register(card);
	if (err < 0)
		goto _error;

	pci_set_drvdata(pci, card);
	++dev;
	return 0;

_error:
	snd_card_free(card);
	return err;
}

static void __devexit snd_bt87x_remove(struct pci_dev *pci)
{
	snd_card_free(pci_get_drvdata(pci));
	pci_set_drvdata(pci, NULL);
}

/* default entries for all Bt87x cards - it's not exported */
/* driver_data is set to 0 to call detection */
static struct pci_device_id snd_bt87x_default_ids[] __devinitdata = {
	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, PCI_ANY_ID, PCI_ANY_ID, 0),
	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_879, PCI_ANY_ID, PCI_ANY_ID, 0),
	{ }
};

static struct pci_driver driver = {
	.name = "Bt87x",
	.id_table = snd_bt87x_ids,
	.probe = snd_bt87x_probe,
	.remove = __devexit_p(snd_bt87x_remove),
};

static int __init alsa_card_bt87x_init(void)
{
	if (load_all)
		driver.id_table = snd_bt87x_default_ids;
	return pci_register_driver(&driver);
}

static void __exit alsa_card_bt87x_exit(void)
{
	pci_unregister_driver(&driver);
}

module_init(alsa_card_bt87x_init)
module_exit(alsa_card_bt87x_exit)