summaryrefslogtreecommitdiff
path: root/sound/soc/mxs/mxs-pcm.c
blob: 965bbbadafea9fa2563931402dea9cf96839d5d4 (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
/*
 * Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved.
 *
 * 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.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

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

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

#include <mach/dma.h>
#include <mach/hardware.h>
#include <mach/dmaengine.h>

#include "mxs-pcm.h"
static const struct snd_pcm_hardware mxs_pcm_hardware = {
	.info			= SNDRV_PCM_INFO_MMAP |
				  SNDRV_PCM_INFO_MMAP_VALID |
				  SNDRV_PCM_INFO_PAUSE |
				  SNDRV_PCM_INFO_RESUME |
				  SNDRV_PCM_INFO_INTERLEAVED,
	.formats		= SNDRV_PCM_FMTBIT_S16_LE |
				  SNDRV_PCM_FMTBIT_S20_3LE |
				  SNDRV_PCM_FMTBIT_S24_LE |
				  SNDRV_PCM_FMTBIT_S32_LE,
	.channels_min		= 2,
	.channels_max		= 2,
	.period_bytes_min	= 32,
	.period_bytes_max	= 8192,
	.periods_min		= 1,
	.periods_max		= 255,
	.buffer_bytes_max	= 64 * 1024,
	.fifo_size		= 32,
};

/*
 * Required to request DMA channels
 */
struct device *mxs_pcm_dev;

struct mxs_runtime_data {
	u32 dma_ch;
	u32 dma_period;
	u32 dma_totsize;
	int format;

	struct mxs_pcm_dma_params *params;
	struct mxs_dma_desc *dma_desc_array[255];
};

static irqreturn_t mxs_pcm_dma_irq(int irq, void *dev_id)
{
	struct snd_pcm_substream *substream = dev_id;
	struct mxs_runtime_data *prtd = substream->runtime->private_data;
	struct mxs_dma_info dma_info;

	mxs_dma_get_info(prtd->dma_ch, &dma_info);

	if (dma_info.status) {
		printk(KERN_WARNING "%s: DMA audio channel %d (%s) error\n",
			__func__, prtd->params->dma_ch, prtd->params->name);
		mxs_dma_ack_irq(prtd->dma_ch);
	} else {
		mxs_dma_ack_irq(prtd->dma_ch);
		snd_pcm_period_elapsed(substream);
	}
	return IRQ_HANDLED;
}

/*
 * Make a circular DMA descriptor list
 */
static int mxs_pcm_prepare(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct mxs_runtime_data *prtd = runtime->private_data;
	dma_addr_t dma_buffer_phys;
	int periods_num, playback, i;

	playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ? 1 : 0;
	periods_num = prtd->dma_totsize / prtd->dma_period;

	dma_buffer_phys = runtime->dma_addr;

	/* Reset DMA channel, enable interrupt */
	mxs_dma_reset(prtd->dma_ch);

	/* Set up a DMA chain to sent DMA buffer */
	for (i = 0; i < periods_num; i++) {
		int ret;
		/* Link with previous command */
		prtd->dma_desc_array[i]->cmd.cmd.bits.bytes = prtd->dma_period;
		prtd->dma_desc_array[i]->cmd.cmd.bits.irq = 1;
		prtd->dma_desc_array[i]->cmd.cmd.bits.chain = 1;
		/* Set DMA direction */
		if (playback)
			prtd->dma_desc_array[i]->cmd.cmd.bits.command = \
				DMA_READ;
		else
			prtd->dma_desc_array[i]->cmd.cmd.bits.command = \
				DMA_WRITE;

		prtd->dma_desc_array[i]->cmd.address = dma_buffer_phys;

		ret = mxs_dma_desc_append(prtd->dma_ch, \
			prtd->dma_desc_array[i]);
		if (ret) {
			printk(KERN_ERR "%s: Failed to append DMA descriptor\n",
		       __func__);
			return ret;
		}
		/* Next data chunk */
		dma_buffer_phys += prtd->dma_period;
	}

	return 0;
}

/*
 * Stop circular DMA descriptor list
 * We should not stop DMA in a middle of current transaction once we receive
 * stop request from ALSA core. This function finds the next DMA descriptor
 * and set it up to decrement DMA channel semaphore. So the current transaction
 * is the last data transfer.
 */
static void mxs_pcm_stop(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct mxs_runtime_data *prtd = runtime->private_data;
	struct mxs_dma_info dma_info;
	int desc;

	/* Freez DMA channel for a moment */
	mxs_dma_freeze(prtd->dma_ch);
	mxs_dma_get_info(prtd->dma_ch, &dma_info);

	desc = (dma_info.buf_addr - runtime->dma_addr) / prtd->dma_period;

	/* Set up the next descriptor to decrement DMA channel sempahore */
	prtd->dma_desc_array[(desc + 1)%8]->cmd.cmd.bits.bytes = 0;
	prtd->dma_desc_array[(desc + 1)%8]->cmd.cmd.bits.pio_words = 0;
	prtd->dma_desc_array[(desc + 1)%8]->cmd.cmd.bits.dec_sem = 1;
	prtd->dma_desc_array[(desc + 1)%8]->cmd.cmd.bits.irq = 0;
	prtd->dma_desc_array[(desc + 1)%8]->cmd.cmd.bits.command = NO_DMA_XFER;

	mxs_dma_unfreeze(prtd->dma_ch);
}

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

	case SNDRV_PCM_TRIGGER_START:
		mxs_dma_enable(prtd->dma_ch);
		break;

	case SNDRV_PCM_TRIGGER_STOP:
		mxs_pcm_stop(substream);
		break;

	case SNDRV_PCM_TRIGGER_RESUME:
	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
		mxs_dma_unfreeze(prtd->dma_ch);
		break;

	case SNDRV_PCM_TRIGGER_SUSPEND:
	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
		mxs_dma_freeze(prtd->dma_ch);
		break;

	default:
		ret = -EINVAL;
		break;
	}

	return ret;
}

static snd_pcm_uframes_t
mxs_pcm_pointer(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct mxs_runtime_data *prtd = runtime->private_data;
	struct mxs_dma_info dma_info;
	unsigned int offset;
	dma_addr_t pos;

	mxs_dma_get_info(prtd->params->dma_ch, &dma_info);
	pos = dma_info.buf_addr;

	offset = bytes_to_frames(runtime, pos - runtime->dma_addr);

	if (offset >= runtime->buffer_size)
		offset = 0;

	return offset;
}

static int mxs_pcm_hw_params(struct snd_pcm_substream *substream,
				  struct snd_pcm_hw_params *hw_params)
{
	struct mxs_runtime_data *prtd = substream->runtime->private_data;

	prtd->dma_period = params_period_bytes(hw_params);
	prtd->dma_totsize = params_buffer_bytes(hw_params);
	prtd->format = params_format(hw_params);

	return snd_pcm_lib_malloc_pages(substream,
					params_buffer_bytes(hw_params));
}

static int mxs_pcm_hw_free(struct snd_pcm_substream *substream)
{
	return snd_pcm_lib_free_pages(substream);
}

static int mxs_pcm_dma_request(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct mxs_runtime_data *prtd = runtime->private_data;
	struct mxs_pcm_dma_params *dma_data = rtd->dai->cpu_dai->dma_data;
	int desc_num = mxs_pcm_hardware.periods_max;
	int desc;
	int ret;

	if (!dma_data)
		return -ENODEV;

	prtd->params = dma_data;
	prtd->dma_ch = dma_data->dma_ch;

	ret = mxs_dma_request(prtd->dma_ch, mxs_pcm_dev,
				   prtd->params->name);
	if (ret) {
		printk(KERN_ERR "%s: Failed to request DMA channel (%d:%d)\n",
		       __func__, dma_data->dma_bus, dma_data->dma_ch);
		return ret;
	}

	/* Allocate memory for data and pio DMA descriptors */
	for (desc = 0; desc < desc_num; desc++) {
		prtd->dma_desc_array[desc] = mxs_dma_alloc_desc();
		if (prtd->dma_desc_array[desc] == NULL) {
			printk(KERN_ERR"%s Unable to allocate DMA command %d\n",
			       __func__, desc);
			goto err;
		}
	}

	ret = request_irq(prtd->params->irq, mxs_pcm_dma_irq, 0,
			  "MXS PCM DMA", substream);
	if (ret) {
		printk(KERN_ERR "%s: Unable to request DMA irq %d\n", __func__,
		       prtd->params->irq);
		goto err;
	}
	/* Enable completion interrupt */
	mxs_dma_ack_irq(prtd->dma_ch);
	mxs_dma_enable_irq(prtd->dma_ch, 1);

	return 0;

err:
	while (--desc >= 0)
		mxs_dma_free_desc(prtd->dma_desc_array[desc]);
	mxs_dma_release(prtd->dma_ch, mxs_pcm_dev);

	return ret;
}

static int mxs_pcm_open(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct mxs_runtime_data *prtd;
	int ret;

	/* Ensure that buffer size is a multiple of the period size */
	ret = snd_pcm_hw_constraint_integer(runtime,
					SNDRV_PCM_HW_PARAM_PERIODS);
	if (ret < 0)
		return ret;

	snd_soc_set_runtime_hwparams(substream, &mxs_pcm_hardware);

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

	runtime->private_data = prtd;

	ret = mxs_pcm_dma_request(substream);
	if (ret) {
		printk(KERN_ERR "mxs_pcm: Failed to request channels\n");
		kfree(prtd);
		return ret;
	}
	return 0;
}

static int mxs_pcm_close(struct snd_pcm_substream *substream)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct mxs_runtime_data *prtd = runtime->private_data;
	int desc_num = mxs_pcm_hardware.periods_max;
	int desc;

	static LIST_HEAD(list);
	mxs_dma_disable(prtd->dma_ch);
	/* Free DMA irq */
	free_irq(prtd->params->irq, substream);
	mxs_dma_get_cooked(prtd->dma_ch, &list);
	/* Free DMA channel*/
	for (desc = 0; desc < desc_num; desc++)
		mxs_dma_free_desc(prtd->dma_desc_array[desc]);
	mxs_dma_release(prtd->dma_ch, mxs_pcm_dev);

	/* Free private runtime data */
	kfree(prtd);
	return 0;
}

static int mcs_pcm_copy(struct snd_pcm_substream *substream, int channel,
			snd_pcm_uframes_t hwoff, void __user *buf,
			snd_pcm_uframes_t frames)
{
	struct snd_pcm_runtime *runtime = substream->runtime;
	struct mxs_runtime_data *prtd = runtime->private_data;
	char *hwbuf = runtime->dma_area + frames_to_bytes(runtime, hwoff);
	unsigned long count = frames_to_bytes(runtime, frames);

	/* For S/PDIF 24-bit playback, fix the buffer.  Code taken from
	   snd_pcm_lib_write_transfer() and snd_pcm_lib_read_transfer()
	   in sound/core/pcm_lib.c */
	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
		if ((prtd->params->dma_ch == MXS_DMA_CHANNEL_AHB_APBX_SPDIF) &&
		    ((prtd->format == SNDRV_PCM_FORMAT_S24_LE)
		     || (prtd->format == SNDRV_PCM_FORMAT_S20_3LE))) {
			if (copy_from_user(hwbuf + 1, buf, count - 1))
				return -EFAULT;
		} else {
			if (copy_from_user(hwbuf, buf, count))
				return -EFAULT;
		}
	} else {
		if (copy_to_user(buf, hwbuf, count))
			return -EFAULT;
	}

	return 0;
}

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

	return dma_mmap_coherent(NULL, vma, runtime->dma_area,
				 runtime->dma_addr, runtime->dma_bytes);
}

struct snd_pcm_ops mxs_pcm_ops = {
	.open		= mxs_pcm_open,
	.close		= mxs_pcm_close,
	.ioctl		= snd_pcm_lib_ioctl,
	.hw_params	= mxs_pcm_hw_params,
	.hw_free	= mxs_pcm_hw_free,
	.prepare	= mxs_pcm_prepare,
	.trigger	= mxs_pcm_trigger,
	.pointer	= mxs_pcm_pointer,
	.copy		= mcs_pcm_copy,
	.mmap		= mxs_pcm_mmap,
};

static u64 mxs_pcm_dma_mask = DMA_BIT_MASK(32);

static int mxs_pcm_new(struct snd_card *card,
			    struct snd_soc_dai *dai, struct snd_pcm *pcm)
{
	size_t size = mxs_pcm_hardware.buffer_bytes_max;

	if (!card->dev->dma_mask)
		card->dev->dma_mask = &mxs_pcm_dma_mask;

	if (!card->dev->coherent_dma_mask)
		card->dev->coherent_dma_mask = DMA_BIT_MASK(32);

	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV, NULL,
					      size, size);

	return 0;
}

static void mxs_pcm_free(struct snd_pcm *pcm)
{
	snd_pcm_lib_preallocate_free_for_all(pcm);
}

/*
 * We need probe/remove callbacks to setup mxs_pcm_dev
 */
static int mxs_pcm_probe(struct platform_device *pdev)
{
	mxs_pcm_dev = &pdev->dev;
	return 0;
}

static int mxs_pcm_remove(struct platform_device *pdev)
{
	mxs_pcm_dev = NULL;
	return 0;
}

struct snd_soc_platform mxs_soc_platform = {
	.name		= "MXS Audio",
	.pcm_ops	= &mxs_pcm_ops,
	.probe		= mxs_pcm_probe,
	.remove		= mxs_pcm_remove,
	.pcm_new	= mxs_pcm_new,
	.pcm_free	= mxs_pcm_free,
};
EXPORT_SYMBOL_GPL(mxs_soc_platform);

static int __init mxs_pcm_init(void)
{
	return snd_soc_register_platform(&mxs_soc_platform);
}

static void __exit mxs_pcm_exit(void)
{
	snd_soc_unregister_platform(&mxs_soc_platform);
}
module_init(mxs_pcm_init);
module_exit(mxs_pcm_exit);

MODULE_AUTHOR("Freescale Semiconductor, Inc.");
MODULE_DESCRIPTION("MXS DMA Module");
MODULE_LICENSE("GPL");