Linux Audio

Check our new training course

Embedded Linux Audio

Check our new training course
with Creative Commons CC-BY-SA
lecture materials

Bootlin logo

Elixir Cross Referencer

Loading...
  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
/* sound/soc/samsung/pcm.c
 *
 * ALSA SoC Audio Layer - S3C PCM-Controller driver
 *
 * Copyright (c) 2009 Samsung Electronics Co. Ltd
 * Author: Jaswinder Singh <jassi.brar@samsung.com>
 * based upon I2S drivers by Ben Dooks.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/clk.h>
#include <linux/io.h>
#include <linux/module.h>

#include <sound/soc.h>
#include <sound/pcm_params.h>

#include <plat/audio.h>
#include <plat/dma.h>

#include "dma.h"
#include "pcm.h"

/*Register Offsets */
#define S3C_PCM_CTL		0x00
#define S3C_PCM_CLKCTL		0x04
#define S3C_PCM_TXFIFO		0x08
#define S3C_PCM_RXFIFO		0x0C
#define S3C_PCM_IRQCTL		0x10
#define S3C_PCM_IRQSTAT		0x14
#define S3C_PCM_FIFOSTAT	0x18
#define S3C_PCM_CLRINT		0x20

/* PCM_CTL Bit-Fields */
#define S3C_PCM_CTL_TXDIPSTICK_MASK	0x3f
#define S3C_PCM_CTL_TXDIPSTICK_SHIFT	13
#define S3C_PCM_CTL_RXDIPSTICK_MASK	0x3f
#define S3C_PCM_CTL_RXDIPSTICK_SHIFT	7
#define S3C_PCM_CTL_TXDMA_EN		(0x1 << 6)
#define S3C_PCM_CTL_RXDMA_EN		(0x1 << 5)
#define S3C_PCM_CTL_TXMSB_AFTER_FSYNC	(0x1 << 4)
#define S3C_PCM_CTL_RXMSB_AFTER_FSYNC	(0x1 << 3)
#define S3C_PCM_CTL_TXFIFO_EN		(0x1 << 2)
#define S3C_PCM_CTL_RXFIFO_EN		(0x1 << 1)
#define S3C_PCM_CTL_ENABLE		(0x1 << 0)

/* PCM_CLKCTL Bit-Fields */
#define S3C_PCM_CLKCTL_SERCLK_EN	(0x1 << 19)
#define S3C_PCM_CLKCTL_SERCLKSEL_PCLK	(0x1 << 18)
#define S3C_PCM_CLKCTL_SCLKDIV_MASK	0x1ff
#define S3C_PCM_CLKCTL_SYNCDIV_MASK	0x1ff
#define S3C_PCM_CLKCTL_SCLKDIV_SHIFT	9
#define S3C_PCM_CLKCTL_SYNCDIV_SHIFT	0

/* PCM_TXFIFO Bit-Fields */
#define S3C_PCM_TXFIFO_DVALID	(0x1 << 16)
#define S3C_PCM_TXFIFO_DATA_MSK	(0xffff << 0)

/* PCM_RXFIFO Bit-Fields */
#define S3C_PCM_RXFIFO_DVALID	(0x1 << 16)
#define S3C_PCM_RXFIFO_DATA_MSK	(0xffff << 0)

/* PCM_IRQCTL Bit-Fields */
#define S3C_PCM_IRQCTL_IRQEN		(0x1 << 14)
#define S3C_PCM_IRQCTL_WRDEN		(0x1 << 12)
#define S3C_PCM_IRQCTL_TXEMPTYEN	(0x1 << 11)
#define S3C_PCM_IRQCTL_TXALMSTEMPTYEN	(0x1 << 10)
#define S3C_PCM_IRQCTL_TXFULLEN		(0x1 << 9)
#define S3C_PCM_IRQCTL_TXALMSTFULLEN	(0x1 << 8)
#define S3C_PCM_IRQCTL_TXSTARVEN	(0x1 << 7)
#define S3C_PCM_IRQCTL_TXERROVRFLEN	(0x1 << 6)
#define S3C_PCM_IRQCTL_RXEMPTEN		(0x1 << 5)
#define S3C_PCM_IRQCTL_RXALMSTEMPTEN	(0x1 << 4)
#define S3C_PCM_IRQCTL_RXFULLEN		(0x1 << 3)
#define S3C_PCM_IRQCTL_RXALMSTFULLEN	(0x1 << 2)
#define S3C_PCM_IRQCTL_RXSTARVEN	(0x1 << 1)
#define S3C_PCM_IRQCTL_RXERROVRFLEN	(0x1 << 0)

/* PCM_IRQSTAT Bit-Fields */
#define S3C_PCM_IRQSTAT_IRQPND		(0x1 << 13)
#define S3C_PCM_IRQSTAT_WRD_XFER	(0x1 << 12)
#define S3C_PCM_IRQSTAT_TXEMPTY		(0x1 << 11)
#define S3C_PCM_IRQSTAT_TXALMSTEMPTY	(0x1 << 10)
#define S3C_PCM_IRQSTAT_TXFULL		(0x1 << 9)
#define S3C_PCM_IRQSTAT_TXALMSTFULL	(0x1 << 8)
#define S3C_PCM_IRQSTAT_TXSTARV		(0x1 << 7)
#define S3C_PCM_IRQSTAT_TXERROVRFL	(0x1 << 6)
#define S3C_PCM_IRQSTAT_RXEMPT		(0x1 << 5)
#define S3C_PCM_IRQSTAT_RXALMSTEMPT	(0x1 << 4)
#define S3C_PCM_IRQSTAT_RXFULL		(0x1 << 3)
#define S3C_PCM_IRQSTAT_RXALMSTFULL	(0x1 << 2)
#define S3C_PCM_IRQSTAT_RXSTARV		(0x1 << 1)
#define S3C_PCM_IRQSTAT_RXERROVRFL	(0x1 << 0)

/* PCM_FIFOSTAT Bit-Fields */
#define S3C_PCM_FIFOSTAT_TXCNT_MSK		(0x3f << 14)
#define S3C_PCM_FIFOSTAT_TXFIFOEMPTY		(0x1 << 13)
#define S3C_PCM_FIFOSTAT_TXFIFOALMSTEMPTY	(0x1 << 12)
#define S3C_PCM_FIFOSTAT_TXFIFOFULL		(0x1 << 11)
#define S3C_PCM_FIFOSTAT_TXFIFOALMSTFULL	(0x1 << 10)
#define S3C_PCM_FIFOSTAT_RXCNT_MSK		(0x3f << 4)
#define S3C_PCM_FIFOSTAT_RXFIFOEMPTY		(0x1 << 3)
#define S3C_PCM_FIFOSTAT_RXFIFOALMSTEMPTY	(0x1 << 2)
#define S3C_PCM_FIFOSTAT_RXFIFOFULL		(0x1 << 1)
#define S3C_PCM_FIFOSTAT_RXFIFOALMSTFULL	(0x1 << 0)

/**
 * struct s3c_pcm_info - S3C PCM Controller information
 * @dev: The parent device passed to use from the probe.
 * @regs: The pointer to the device register block.
 * @dma_playback: DMA information for playback channel.
 * @dma_capture: DMA information for capture channel.
 */
struct s3c_pcm_info {
	spinlock_t lock;
	struct device	*dev;
	void __iomem	*regs;

	unsigned int sclk_per_fs;

	/* Whether to keep PCMSCLK enabled even when idle(no active xfer) */
	unsigned int idleclk;

	struct clk	*pclk;
	struct clk	*cclk;

	struct s3c_dma_params	*dma_playback;
	struct s3c_dma_params	*dma_capture;
};

static struct s3c2410_dma_client s3c_pcm_dma_client_out = {
	.name		= "PCM Stereo out"
};

static struct s3c2410_dma_client s3c_pcm_dma_client_in = {
	.name		= "PCM Stereo in"
};

static struct s3c_dma_params s3c_pcm_stereo_out[] = {
	[0] = {
		.client		= &s3c_pcm_dma_client_out,
		.dma_size	= 4,
	},
	[1] = {
		.client		= &s3c_pcm_dma_client_out,
		.dma_size	= 4,
	},
};

static struct s3c_dma_params s3c_pcm_stereo_in[] = {
	[0] = {
		.client		= &s3c_pcm_dma_client_in,
		.dma_size	= 4,
	},
	[1] = {
		.client		= &s3c_pcm_dma_client_in,
		.dma_size	= 4,
	},
};

static struct s3c_pcm_info s3c_pcm[2];

static void s3c_pcm_snd_txctrl(struct s3c_pcm_info *pcm, int on)
{
	void __iomem *regs = pcm->regs;
	u32 ctl, clkctl;

	clkctl = readl(regs + S3C_PCM_CLKCTL);
	ctl = readl(regs + S3C_PCM_CTL);
	ctl &= ~(S3C_PCM_CTL_TXDIPSTICK_MASK
			 << S3C_PCM_CTL_TXDIPSTICK_SHIFT);

	if (on) {
		ctl |= S3C_PCM_CTL_TXDMA_EN;
		ctl |= S3C_PCM_CTL_TXFIFO_EN;
		ctl |= S3C_PCM_CTL_ENABLE;
		ctl |= (0x4<<S3C_PCM_CTL_TXDIPSTICK_SHIFT);
		clkctl |= S3C_PCM_CLKCTL_SERCLK_EN;
	} else {
		ctl &= ~S3C_PCM_CTL_TXDMA_EN;
		ctl &= ~S3C_PCM_CTL_TXFIFO_EN;

		if (!(ctl & S3C_PCM_CTL_RXFIFO_EN)) {
			ctl &= ~S3C_PCM_CTL_ENABLE;
			if (!pcm->idleclk)
				clkctl |= S3C_PCM_CLKCTL_SERCLK_EN;
		}
	}

	writel(clkctl, regs + S3C_PCM_CLKCTL);
	writel(ctl, regs + S3C_PCM_CTL);
}

static void s3c_pcm_snd_rxctrl(struct s3c_pcm_info *pcm, int on)
{
	void __iomem *regs = pcm->regs;
	u32 ctl, clkctl;

	ctl = readl(regs + S3C_PCM_CTL);
	clkctl = readl(regs + S3C_PCM_CLKCTL);
	ctl &= ~(S3C_PCM_CTL_RXDIPSTICK_MASK
			 << S3C_PCM_CTL_RXDIPSTICK_SHIFT);

	if (on) {
		ctl |= S3C_PCM_CTL_RXDMA_EN;
		ctl |= S3C_PCM_CTL_RXFIFO_EN;
		ctl |= S3C_PCM_CTL_ENABLE;
		ctl |= (0x20<<S3C_PCM_CTL_RXDIPSTICK_SHIFT);
		clkctl |= S3C_PCM_CLKCTL_SERCLK_EN;
	} else {
		ctl &= ~S3C_PCM_CTL_RXDMA_EN;
		ctl &= ~S3C_PCM_CTL_RXFIFO_EN;

		if (!(ctl & S3C_PCM_CTL_TXFIFO_EN)) {
			ctl &= ~S3C_PCM_CTL_ENABLE;
			if (!pcm->idleclk)
				clkctl |= S3C_PCM_CLKCTL_SERCLK_EN;
		}
	}

	writel(clkctl, regs + S3C_PCM_CLKCTL);
	writel(ctl, regs + S3C_PCM_CTL);
}

static int s3c_pcm_trigger(struct snd_pcm_substream *substream, int cmd,
			       struct snd_soc_dai *dai)
{
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct s3c_pcm_info *pcm = snd_soc_dai_get_drvdata(rtd->cpu_dai);
	unsigned long flags;

	dev_dbg(pcm->dev, "Entered %s\n", __func__);

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
		spin_lock_irqsave(&pcm->lock, flags);

		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
			s3c_pcm_snd_rxctrl(pcm, 1);
		else
			s3c_pcm_snd_txctrl(pcm, 1);

		spin_unlock_irqrestore(&pcm->lock, flags);
		break;

	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
		spin_lock_irqsave(&pcm->lock, flags);

		if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
			s3c_pcm_snd_rxctrl(pcm, 0);
		else
			s3c_pcm_snd_txctrl(pcm, 0);

		spin_unlock_irqrestore(&pcm->lock, flags);
		break;

	default:
		return -EINVAL;
	}

	return 0;
}

static int s3c_pcm_hw_params(struct snd_pcm_substream *substream,
				 struct snd_pcm_hw_params *params,
				 struct snd_soc_dai *socdai)
{
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct s3c_pcm_info *pcm = snd_soc_dai_get_drvdata(rtd->cpu_dai);
	struct s3c_dma_params *dma_data;
	void __iomem *regs = pcm->regs;
	struct clk *clk;
	int sclk_div, sync_div;
	unsigned long flags;
	u32 clkctl;

	dev_dbg(pcm->dev, "Entered %s\n", __func__);

	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
		dma_data = pcm->dma_playback;
	else
		dma_data = pcm->dma_capture;

	snd_soc_dai_set_dma_data(rtd->cpu_dai, substream, dma_data);

	/* Strictly check for sample size */
	switch (params_format(params)) {
	case SNDRV_PCM_FORMAT_S16_LE:
		break;
	default:
		return -EINVAL;
	}

	spin_lock_irqsave(&pcm->lock, flags);

	/* Get hold of the PCMSOURCE_CLK */
	clkctl = readl(regs + S3C_PCM_CLKCTL);
	if (clkctl & S3C_PCM_CLKCTL_SERCLKSEL_PCLK)
		clk = pcm->pclk;
	else
		clk = pcm->cclk;

	/* Set the SCLK divider */
	sclk_div = clk_get_rate(clk) / pcm->sclk_per_fs /
					params_rate(params) / 2 - 1;

	clkctl &= ~(S3C_PCM_CLKCTL_SCLKDIV_MASK
			<< S3C_PCM_CLKCTL_SCLKDIV_SHIFT);
	clkctl |= ((sclk_div & S3C_PCM_CLKCTL_SCLKDIV_MASK)
			<< S3C_PCM_CLKCTL_SCLKDIV_SHIFT);

	/* Set the SYNC divider */
	sync_div = pcm->sclk_per_fs - 1;

	clkctl &= ~(S3C_PCM_CLKCTL_SYNCDIV_MASK
				<< S3C_PCM_CLKCTL_SYNCDIV_SHIFT);
	clkctl |= ((sync_div & S3C_PCM_CLKCTL_SYNCDIV_MASK)
				<< S3C_PCM_CLKCTL_SYNCDIV_SHIFT);

	writel(clkctl, regs + S3C_PCM_CLKCTL);

	spin_unlock_irqrestore(&pcm->lock, flags);

	dev_dbg(pcm->dev, "PCMSOURCE_CLK-%lu SCLK=%ufs SCLK_DIV=%d SYNC_DIV=%d\n",
				clk_get_rate(clk), pcm->sclk_per_fs,
				sclk_div, sync_div);

	return 0;
}

static int s3c_pcm_set_fmt(struct snd_soc_dai *cpu_dai,
			       unsigned int fmt)
{
	struct s3c_pcm_info *pcm = snd_soc_dai_get_drvdata(cpu_dai);
	void __iomem *regs = pcm->regs;
	unsigned long flags;
	int ret = 0;
	u32 ctl;

	dev_dbg(pcm->dev, "Entered %s\n", __func__);

	spin_lock_irqsave(&pcm->lock, flags);

	ctl = readl(regs + S3C_PCM_CTL);

	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
	case SND_SOC_DAIFMT_IB_NF:
		/* Nothing to do, IB_NF by default */
		break;
	default:
		dev_err(pcm->dev, "Unsupported clock inversion!\n");
		ret = -EINVAL;
		goto exit;
	}

	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
	case SND_SOC_DAIFMT_CBS_CFS:
		/* Nothing to do, Master by default */
		break;
	default:
		dev_err(pcm->dev, "Unsupported master/slave format!\n");
		ret = -EINVAL;
		goto exit;
	}

	switch (fmt & SND_SOC_DAIFMT_CLOCK_MASK) {
	case SND_SOC_DAIFMT_CONT:
		pcm->idleclk = 1;
		break;
	case SND_SOC_DAIFMT_GATED:
		pcm->idleclk = 0;
		break;
	default:
		dev_err(pcm->dev, "Invalid Clock gating request!\n");
		ret = -EINVAL;
		goto exit;
	}

	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
	case SND_SOC_DAIFMT_DSP_A:
		ctl |= S3C_PCM_CTL_TXMSB_AFTER_FSYNC;
		ctl |= S3C_PCM_CTL_RXMSB_AFTER_FSYNC;
		break;
	case SND_SOC_DAIFMT_DSP_B:
		ctl &= ~S3C_PCM_CTL_TXMSB_AFTER_FSYNC;
		ctl &= ~S3C_PCM_CTL_RXMSB_AFTER_FSYNC;
		break;
	default:
		dev_err(pcm->dev, "Unsupported data format!\n");
		ret = -EINVAL;
		goto exit;
	}

	writel(ctl, regs + S3C_PCM_CTL);

exit:
	spin_unlock_irqrestore(&pcm->lock, flags);

	return ret;
}

static int s3c_pcm_set_clkdiv(struct snd_soc_dai *cpu_dai,
						int div_id, int div)
{
	struct s3c_pcm_info *pcm = snd_soc_dai_get_drvdata(cpu_dai);

	switch (div_id) {
	case S3C_PCM_SCLK_PER_FS:
		pcm->sclk_per_fs = div;
		break;

	default:
		return -EINVAL;
	}

	return 0;
}

static int s3c_pcm_set_sysclk(struct snd_soc_dai *cpu_dai,
				  int clk_id, unsigned int freq, int dir)
{
	struct s3c_pcm_info *pcm = snd_soc_dai_get_drvdata(cpu_dai);
	void __iomem *regs = pcm->regs;
	u32 clkctl = readl(regs + S3C_PCM_CLKCTL);

	switch (clk_id) {
	case S3C_PCM_CLKSRC_PCLK:
		clkctl |= S3C_PCM_CLKCTL_SERCLKSEL_PCLK;
		break;

	case S3C_PCM_CLKSRC_MUX:
		clkctl &= ~S3C_PCM_CLKCTL_SERCLKSEL_PCLK;

		if (clk_get_rate(pcm->cclk) != freq)
			clk_set_rate(pcm->cclk, freq);

		break;

	default:
		return -EINVAL;
	}

	writel(clkctl, regs + S3C_PCM_CLKCTL);

	return 0;
}

static struct snd_soc_dai_ops s3c_pcm_dai_ops = {
	.set_sysclk	= s3c_pcm_set_sysclk,
	.set_clkdiv	= s3c_pcm_set_clkdiv,
	.trigger	= s3c_pcm_trigger,
	.hw_params	= s3c_pcm_hw_params,
	.set_fmt	= s3c_pcm_set_fmt,
};

#define S3C_PCM_RATES  SNDRV_PCM_RATE_8000_96000

#define S3C_PCM_DAI_DECLARE			\
	.symmetric_rates = 1,					\
	.ops = &s3c_pcm_dai_ops,				\
	.playback = {						\
		.channels_min	= 2,				\
		.channels_max	= 2,				\
		.rates		= S3C_PCM_RATES,		\
		.formats	= SNDRV_PCM_FMTBIT_S16_LE,	\
	},							\
	.capture = {						\
		.channels_min	= 2,				\
		.channels_max	= 2,				\
		.rates		= S3C_PCM_RATES,		\
		.formats	= SNDRV_PCM_FMTBIT_S16_LE,	\
	}

struct snd_soc_dai_driver s3c_pcm_dai[] = {
	[0] = {
		.name	= "samsung-pcm.0",
		S3C_PCM_DAI_DECLARE,
	},
	[1] = {
		.name	= "samsung-pcm.1",
		S3C_PCM_DAI_DECLARE,
	},
};
EXPORT_SYMBOL_GPL(s3c_pcm_dai);

static __devinit int s3c_pcm_dev_probe(struct platform_device *pdev)
{
	struct s3c_pcm_info *pcm;
	struct resource *mem_res, *dmatx_res, *dmarx_res;
	struct s3c_audio_pdata *pcm_pdata;
	int ret;

	/* Check for valid device index */
	if ((pdev->id < 0) || pdev->id >= ARRAY_SIZE(s3c_pcm)) {
		dev_err(&pdev->dev, "id %d out of range\n", pdev->id);
		return -EINVAL;
	}

	pcm_pdata = pdev->dev.platform_data;

	/* Check for availability of necessary resource */
	dmatx_res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
	if (!dmatx_res) {
		dev_err(&pdev->dev, "Unable to get PCM-TX dma resource\n");
		return -ENXIO;
	}

	dmarx_res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
	if (!dmarx_res) {
		dev_err(&pdev->dev, "Unable to get PCM-RX dma resource\n");
		return -ENXIO;
	}

	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!mem_res) {
		dev_err(&pdev->dev, "Unable to get register resource\n");
		return -ENXIO;
	}

	if (pcm_pdata && pcm_pdata->cfg_gpio && pcm_pdata->cfg_gpio(pdev)) {
		dev_err(&pdev->dev, "Unable to configure gpio\n");
		return -EINVAL;
	}

	pcm = &s3c_pcm[pdev->id];
	pcm->dev = &pdev->dev;

	spin_lock_init(&pcm->lock);

	/* Default is 128fs */
	pcm->sclk_per_fs = 128;

	pcm->cclk = clk_get(&pdev->dev, "audio-bus");
	if (IS_ERR(pcm->cclk)) {
		dev_err(&pdev->dev, "failed to get audio-bus\n");
		ret = PTR_ERR(pcm->cclk);
		goto err1;
	}
	clk_enable(pcm->cclk);

	/* record our pcm structure for later use in the callbacks */
	dev_set_drvdata(&pdev->dev, pcm);

	if (!request_mem_region(mem_res->start,
				resource_size(mem_res), "samsung-pcm")) {
		dev_err(&pdev->dev, "Unable to request register region\n");
		ret = -EBUSY;
		goto err2;
	}

	pcm->regs = ioremap(mem_res->start, 0x100);
	if (pcm->regs == NULL) {
		dev_err(&pdev->dev, "cannot ioremap registers\n");
		ret = -ENXIO;
		goto err3;
	}

	pcm->pclk = clk_get(&pdev->dev, "pcm");
	if (IS_ERR(pcm->pclk)) {
		dev_err(&pdev->dev, "failed to get pcm_clock\n");
		ret = -ENOENT;
		goto err4;
	}
	clk_enable(pcm->pclk);

	ret = snd_soc_register_dai(&pdev->dev, &s3c_pcm_dai[pdev->id]);
	if (ret != 0) {
		dev_err(&pdev->dev, "failed to get pcm_clock\n");
		goto err5;
	}

	s3c_pcm_stereo_in[pdev->id].dma_addr = mem_res->start
							+ S3C_PCM_RXFIFO;
	s3c_pcm_stereo_out[pdev->id].dma_addr = mem_res->start
							+ S3C_PCM_TXFIFO;

	s3c_pcm_stereo_in[pdev->id].channel = dmarx_res->start;
	s3c_pcm_stereo_out[pdev->id].channel = dmatx_res->start;

	pcm->dma_capture = &s3c_pcm_stereo_in[pdev->id];
	pcm->dma_playback = &s3c_pcm_stereo_out[pdev->id];

	return 0;

err5:
	clk_disable(pcm->pclk);
	clk_put(pcm->pclk);
err4:
	iounmap(pcm->regs);
err3:
	release_mem_region(mem_res->start, resource_size(mem_res));
err2:
	clk_disable(pcm->cclk);
	clk_put(pcm->cclk);
err1:
	return ret;
}

static __devexit int s3c_pcm_dev_remove(struct platform_device *pdev)
{
	struct s3c_pcm_info *pcm = &s3c_pcm[pdev->id];
	struct resource *mem_res;

	snd_soc_unregister_dai(&pdev->dev);

	iounmap(pcm->regs);

	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	release_mem_region(mem_res->start, resource_size(mem_res));

	clk_disable(pcm->cclk);
	clk_disable(pcm->pclk);
	clk_put(pcm->pclk);
	clk_put(pcm->cclk);

	return 0;
}

static struct platform_driver s3c_pcm_driver = {
	.probe  = s3c_pcm_dev_probe,
	.remove = __devexit_p(s3c_pcm_dev_remove),
	.driver = {
		.name = "samsung-pcm",
		.owner = THIS_MODULE,
	},
};

static int __init s3c_pcm_init(void)
{
	return platform_driver_register(&s3c_pcm_driver);
}
module_init(s3c_pcm_init);

static void __exit s3c_pcm_exit(void)
{
	platform_driver_unregister(&s3c_pcm_driver);
}
module_exit(s3c_pcm_exit);

/* Module information */
MODULE_AUTHOR("Jaswinder Singh, <jassi.brar@samsung.com>");
MODULE_DESCRIPTION("S3C PCM Controller Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:samsung-pcm");