summaryrefslogtreecommitdiffstats
path: root/sound/soc/s3c24xx/s3c24xx-pcm.c
blob: 4107a87d4de3cb39fdcf7f8d51432e5a37361c93 (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
/*
 * s3c24xx-pcm.c  --  ALSA Soc Audio Layer
 *
 * (c) 2006 Wolfson Microelectronics PLC.
 * Graeme Gregory graeme.gregory@wolfsonmicro.com or linux@wolfsonmicro.com
 *
 * (c) 2004-2005 Simtec Electronics
 *	http://armlinux.simtec.co.uk/
 *	Ben Dooks <ben@simtec.co.uk>
 *
 *  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.
 *
 *  Revision history
 *    11th Dec 2006   Merged with Simtec driver
 *    10th Nov 2006   Initial version.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>

#include <sound/driver.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>

#include <asm/dma.h>
#include <asm/io.h>
#include <asm/hardware.h>
#include <asm/arch/dma.h>
#include <asm/arch/audio.h>

#include "s3c24xx-pcm.h"

#define S3C24XX_PCM_DEBUG 0
#if S3C24XX_PCM_DEBUG
#define DBG(x...) printk(KERN_DEBUG x)
#else
#define DBG(x...)
#endif

static const struct snd_pcm_hardware s3c24xx_pcm_hardware = {
	.info			= SNDRV_PCM_INFO_INTERLEAVED |
				    SNDRV_PCM_INFO_BLOCK_TRANSFER |
				    SNDRV_PCM_INFO_MMAP |
				    SNDRV_PCM_INFO_MMAP_VALID,
	.formats		= SNDRV_PCM_FMTBIT_S16_LE |
				    SNDRV_PCM_FMTBIT_U16_LE |
				    SNDRV_PCM_FMTBIT_U8 |
				    SNDRV_PCM_FMTBIT_S8,
	.channels_min		= 2,
	.channels_max		= 2,
	.buffer_bytes_max	= 128*1024,
	.period_bytes_min	= PAGE_SIZE,
	.period_bytes_max	= PAGE_SIZE*2,
	.periods_min		= 2,
	.periods_max		= 128,
	.fifo_size		= 32,
};

struct s3c24xx_runtime_data {
	spinlock_t lock;
	int state;
	unsigned int dma_loaded;
	unsigned int dma_limit;
	unsigned int dma_period;
	dma_addr_t dma_start;
	dma_addr_t dma_pos;
	dma_addr_t dma_end;
	struct s3c24xx_pcm_dma_params *params;
};

/* s3c24xx_pcm_enqueue
 *
 * place a dma buffer onto the queue for the dma system
 * to handle.
*/
static void s3c24xx_pcm_enqueue(struct snd_pcm_substream *substream)
{
	struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
	dma_addr_t pos = prtd->dma_pos;
	int ret;

	DBG("Entered %s\n", __FUNCTION__);

	while (prtd->dma_loaded < prtd->dma_limit) {
		unsigned long len = prtd->dma_period;

		DBG("dma_loaded: %d\n",prtd->dma_loaded);

		if ((pos + len) > prtd->dma_end) {
			len  = prtd->dma_end - pos;
			DBG(KERN_DEBUG "%s: corrected dma len %ld\n",
			       __FUNCTION__, len);
		}

		ret = s3c2410_dma_enqueue(prtd->params->channel, 
			substream, pos, len);

		if (ret == 0) {
			prtd->dma_loaded++;
			pos += prtd->dma_period;
			if (pos >= prtd->dma_end)
				pos = prtd->dma_start;
		} else
			break;
	}

	prtd->dma_pos = pos;
}

static void s3c24xx_audio_buffdone(struct s3c2410_dma_chan *channel,
				void *dev_id, int size,
				enum s3c2410_dma_buffresult result)
{
	struct snd_pcm_substream *substream = dev_id;
	struct s3c24xx_runtime_data *prtd;

	DBG("Entered %s\n", __FUNCTION__);

	if (result == S3C2410_RES_ABORT || result == S3C2410_RES_ERR)
		return;

	prtd = substream->runtime->private_data;
	
	if (substream)
		snd_pcm_period_elapsed(substream);

	spin_lock(&prtd->lock);
	if (prtd->state & ST_RUNNING) {
		prtd->dma_loaded--;
		s3c24xx_pcm_enqueue(substream);
	}

	spin_unlock(&prtd->lock);
}

static int s3c24xx_pcm_hw_params(struct snd_pcm_substream *substream,
	struct snd_pcm_hw_params *params)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct s3c24xx_runtime_data *prtd = runtime->private_data;
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct s3c24xx_pcm_dma_params *dma = rtd->dai->cpu_dai->dma_data;
	unsigned long totbytes = params_buffer_bytes(params);
	int ret=0;

	DBG("Entered %s\n", __FUNCTION__);

	/* return if this is a bufferless transfer e.g.
	 * codec <--> BT codec or GSM modem -- lg FIXME */
	if (!dma)
		return 0;

	/* this may get called several times by oss emulation
	 * with different params -HW */
	if (prtd->params == NULL) {
		/* prepare DMA */
		prtd->params = dma;

		DBG("params %p, client %p, channel %d\n", prtd->params,
			prtd->params->client, prtd->params->channel);

		ret = s3c2410_dma_request(prtd->params->channel,
					  prtd->params->client, NULL);

		if (ret) {
			DBG(KERN_ERR "failed to get dma channel\n");
			return ret;
		}
	}

	/* channel needs configuring for mem=>device, increment memory addr,
	 * sync to pclk, half-word transfers to the IIS-FIFO. */
	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
		s3c2410_dma_devconfig(prtd->params->channel,
				S3C2410_DMASRC_MEM, S3C2410_DISRCC_INC |
				S3C2410_DISRCC_APB, prtd->params->dma_addr);

		s3c2410_dma_config(prtd->params->channel,
				prtd->params->dma_size,
				S3C2410_DCON_SYNC_PCLK | 
				S3C2410_DCON_HANDSHAKE);
	} else {
		s3c2410_dma_config(prtd->params->channel,
				prtd->params->dma_size,
				S3C2410_DCON_HANDSHAKE | 
				S3C2410_DCON_SYNC_PCLK);

		s3c2410_dma_devconfig(prtd->params->channel,
					S3C2410_DMASRC_HW, 0x3,
					prtd->params->dma_addr);
	}

	s3c2410_dma_set_buffdone_fn(prtd->params->channel,
				    s3c24xx_audio_buffdone);

	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);

	runtime->dma_bytes = totbytes;

	spin_lock_irq(&prtd->lock);
	prtd->dma_loaded = 0;
	prtd->dma_limit = runtime->hw.periods_min;
	prtd->dma_period = params_period_bytes(params);
	prtd->dma_start = runtime->dma_addr;
	prtd->dma_pos = prtd->dma_start;
	prtd->dma_end = prtd->dma_start + totbytes;
	spin_unlock_irq(&prtd->lock);

	return 0;
}

static int s3c24xx_pcm_hw_free(struct snd_pcm_substream *substream)
{
	struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;

	DBG("Entered %s\n", __FUNCTION__);

	/* TODO - do we need to ensure DMA flushed */
	snd_pcm_set_runtime_buffer(substream, NULL);

	if (prtd->params) {
		s3c2410_dma_free(prtd->params->channel, prtd->params->client);
		prtd->params = NULL;
	}

	return 0;
}

static int s3c24xx_pcm_prepare(struct snd_pcm_substream *substream)
{
	struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
	int ret = 0;

	DBG("Entered %s\n", __FUNCTION__);

	/* return if this is a bufferless transfer e.g.
	 * codec <--> BT codec or GSM modem -- lg FIXME */
	if (!prtd->params)
	 	return 0;

	/* flush the DMA channel */
	s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_FLUSH);
	prtd->dma_loaded = 0;
	prtd->dma_pos = prtd->dma_start;

	/* enqueue dma buffers */
	s3c24xx_pcm_enqueue(substream);

	return ret;
}

static int s3c24xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
{
	struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
	int ret = 0;

	DBG("Entered %s\n", __FUNCTION__);

	spin_lock(&prtd->lock);

	switch (cmd) {
	case SNDRV_PCM_TRIGGER_START:
	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
		prtd->state |= ST_RUNNING;
		s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_START);
		s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_STARTED);
		break;

	case SNDRV_PCM_TRIGGER_STOP:
	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
		prtd->state &= ~ST_RUNNING;
		s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_STOP);
		break;

	default:
		ret = -EINVAL;
		break;
	}

	spin_unlock(&prtd->lock);

	return ret;
}

static snd_pcm_uframes_t 
	s3c24xx_pcm_pointer(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct s3c24xx_runtime_data *prtd = runtime->private_data;
	unsigned long res;
	dma_addr_t src, dst;

	DBG("Entered %s\n", __FUNCTION__);

	spin_lock(&prtd->lock);
	s3c2410_dma_getposition(prtd->params->channel, &src, &dst);

	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
		res = dst - prtd->dma_start;
	else
		res = src - prtd->dma_start;

	spin_unlock(&prtd->lock);

	DBG("Pointer %x %x\n",src,dst);

	/* we seem to be getting the odd error from the pcm library due
	 * to out-of-bounds pointers. this is maybe due to the dma engine
	 * not having loaded the new values for the channel before being
	 * callled... (todo - fix )
	 */

	if (res >= snd_pcm_lib_buffer_bytes(substream)) {
		if (res == snd_pcm_lib_buffer_bytes(substream))
			res = 0;
	}

	return bytes_to_frames(substream->runtime, res);
}

static int s3c24xx_pcm_open(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct s3c24xx_runtime_data *prtd;

	DBG("Entered %s\n", __FUNCTION__);

	snd_soc_set_runtime_hwparams(substream, &s3c24xx_pcm_hardware);

	prtd = kzalloc(sizeof(struct s3c24xx_runtime_data), GFP_KERNEL);
	if (prtd == NULL)
		return -ENOMEM;

	spin_lock_init(&prtd->lock);

	runtime->private_data = prtd;
	return 0;
}

static int s3c24xx_pcm_close(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct s3c24xx_runtime_data *prtd = runtime->private_data;

	DBG("Entered %s\n", __FUNCTION__);

	if (prtd)
		kfree(prtd);
	else
		DBG("s3c24xx_pcm_close called with prtd == NULL\n");

	return 0;
}

static int s3c24xx_pcm_mmap(struct snd_pcm_substream *substream,
	struct vm_area_struct *vma)
{
	struct snd_pcm_runtime *runtime = substream->runtime;

	DBG("Entered %s\n", __FUNCTION__);

	return dma_mmap_writecombine(substream->pcm->card->dev, vma,
                                     runtime->dma_area,
                                     runtime->dma_addr,
                                     runtime->dma_bytes);
}

static struct snd_pcm_ops s3c24xx_pcm_ops = {
	.open		= s3c24xx_pcm_open,
	.close		= s3c24xx_pcm_close,
	.ioctl		= snd_pcm_lib_ioctl,
	.hw_params	= s3c24xx_pcm_hw_params,
	.hw_free	= s3c24xx_pcm_hw_free,
	.prepare	= s3c24xx_pcm_prepare,
	.trigger	= s3c24xx_pcm_trigger,
	.pointer	= s3c24xx_pcm_pointer,
	.mmap		= s3c24xx_pcm_mmap,
};

static int s3c24xx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
{
	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
	struct snd_dma_buffer *buf = &substream->dma_buffer;
	size_t size = s3c24xx_pcm_hardware.buffer_bytes_max;

	DBG("Entered %s\n", __FUNCTION__);

	buf->dev.type = SNDRV_DMA_TYPE_DEV;
	buf->dev.dev = pcm->card->dev;
	buf->private_data = NULL;
	buf->area = dma_alloc_writecombine(pcm->card->dev, size,
					   &buf->addr, GFP_KERNEL);
	if (!buf->area)
		return -ENOMEM;
	buf->bytes = size;
	return 0;
}

static void s3c24xx_pcm_free_dma_buffers(struct snd_pcm *pcm)
{
	struct snd_pcm_substream *substream;
	struct snd_dma_buffer *buf;
	int stream;

	DBG("Entered %s\n", __FUNCTION__);

	for (stream = 0; stream < 2; stream++) {
		substream = pcm->streams[stream].substream;
		if (!substream)
			continue;

		buf = &substream->dma_buffer;
		if (!buf->area)
			continue;

		dma_free_writecombine(pcm->card->dev, buf->bytes,
				      buf->area, buf->addr);
		buf->area = NULL;
	}
}

static u64 s3c24xx_pcm_dmamask = DMA_32BIT_MASK;

static int s3c24xx_pcm_new(struct snd_card *card, 
	struct snd_soc_codec_dai *dai, struct snd_pcm *pcm)
{
	int ret = 0;

	DBG("Entered %s\n", __FUNCTION__);

	if (!card->dev->dma_mask)
		card->dev->dma_mask = &s3c24xx_pcm_dmamask;
	if (!card->dev->coherent_dma_mask)
		card->dev->coherent_dma_mask = 0xffffffff;

	if (dai->playback.channels_min) {
		ret = s3c24xx_pcm_preallocate_dma_buffer(pcm,
			SNDRV_PCM_STREAM_PLAYBACK);
		if (ret)
			goto out;
	}

	if (dai->capture.channels_min) {
		ret = s3c24xx_pcm_preallocate_dma_buffer(pcm,
			SNDRV_PCM_STREAM_CAPTURE);
		if (ret)
			goto out;
	}
 out:
	return ret;
}

struct snd_soc_platform s3c24xx_soc_platform = {
	.name		= "s3c24xx-audio",
	.pcm_ops 	= &s3c24xx_pcm_ops,
	.pcm_new	= s3c24xx_pcm_new,
	.pcm_free	= s3c24xx_pcm_free_dma_buffers,
};

EXPORT_SYMBOL_GPL(s3c24xx_soc_platform);

MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
MODULE_DESCRIPTION("Samsung S3C24XX PCM DMA module");
MODULE_LICENSE("GPL");