1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * edma-pcm.c - eDMA PCM driver using dmaengine for AM3xxx, AM4xxx
4 *
5 * Copyright (C) 2014 Texas Instruments, Inc.
6 *
7 * Author: Peter Ujfalusi <peter.ujfalusi@ti.com>
8 *
9 * Based on: sound/soc/tegra/tegra_pcm.c
10 */
11
12#include <linux/module.h>
13#include <sound/core.h>
14#include <sound/pcm.h>
15#include <sound/pcm_params.h>
16#include <sound/soc.h>
17#include <sound/dmaengine_pcm.h>
18
19#include "edma-pcm.h"
20
21static const struct snd_pcm_hardware edma_pcm_hardware = {
22 .info = SNDRV_PCM_INFO_MMAP |
23 SNDRV_PCM_INFO_MMAP_VALID |
24 SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME |
25 SNDRV_PCM_INFO_NO_PERIOD_WAKEUP |
26 SNDRV_PCM_INFO_INTERLEAVED,
27 .buffer_bytes_max = 128 * 1024,
28 .period_bytes_min = 32,
29 .period_bytes_max = 64 * 1024,
30 .periods_min = 2,
31 .periods_max = 19, /* Limit by edma dmaengine driver */
32};
33
34static const struct snd_dmaengine_pcm_config edma_dmaengine_pcm_config = {
35 .pcm_hardware = &edma_pcm_hardware,
36 .prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
37 .prealloc_buffer_size = 128 * 1024,
38};
39
40int edma_pcm_platform_register(struct device *dev)
41{
42 struct snd_dmaengine_pcm_config *config;
43
44 if (dev->of_node)
45 return devm_snd_dmaengine_pcm_register(dev,
46 config: &edma_dmaengine_pcm_config, flags: 0);
47
48 config = devm_kzalloc(dev, size: sizeof(*config), GFP_KERNEL);
49 if (!config)
50 return -ENOMEM;
51
52 *config = edma_dmaengine_pcm_config;
53
54 config->chan_names[0] = "tx";
55 config->chan_names[1] = "rx";
56
57 return devm_snd_dmaengine_pcm_register(dev, config, flags: 0);
58}
59EXPORT_SYMBOL_GPL(edma_pcm_platform_register);
60
61MODULE_AUTHOR("Peter Ujfalusi <peter.ujfalusi@ti.com>");
62MODULE_DESCRIPTION("eDMA PCM ASoC platform driver");
63MODULE_LICENSE("GPL");
64

source code of linux/sound/soc/ti/edma-pcm.c