xref: /openbmc/linux/sound/soc/fsl/imx-pcm-dma.c (revision cd5d5810)
1 /*
2  * imx-pcm-dma-mx2.c  --  ALSA Soc Audio Layer
3  *
4  * Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
5  *
6  * This code is based on code copyrighted by Freescale,
7  * Liam Girdwood, Javier Martin and probably others.
8  *
9  *  This program is free software; you can redistribute  it and/or modify it
10  *  under  the terms of  the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the  License, or (at your
12  *  option) any later version.
13  */
14 #include <linux/platform_device.h>
15 #include <linux/dmaengine.h>
16 #include <linux/types.h>
17 #include <linux/module.h>
18 
19 #include <sound/core.h>
20 #include <sound/pcm.h>
21 #include <sound/soc.h>
22 #include <sound/dmaengine_pcm.h>
23 
24 #include "imx-pcm.h"
25 
26 static bool filter(struct dma_chan *chan, void *param)
27 {
28 	struct snd_dmaengine_dai_dma_data *dma_data = param;
29 
30 	if (!imx_dma_is_general_purpose(chan))
31 		return false;
32 
33 	chan->private = dma_data->filter_data;
34 
35 	return true;
36 }
37 
38 static const struct snd_pcm_hardware imx_pcm_hardware = {
39 	.info = SNDRV_PCM_INFO_INTERLEAVED |
40 		SNDRV_PCM_INFO_BLOCK_TRANSFER |
41 		SNDRV_PCM_INFO_MMAP |
42 		SNDRV_PCM_INFO_MMAP_VALID |
43 		SNDRV_PCM_INFO_PAUSE |
44 		SNDRV_PCM_INFO_RESUME,
45 	.formats = SNDRV_PCM_FMTBIT_S16_LE,
46 	.rate_min = 8000,
47 	.channels_min = 2,
48 	.channels_max = 2,
49 	.buffer_bytes_max = IMX_SSI_DMABUF_SIZE,
50 	.period_bytes_min = 128,
51 	.period_bytes_max = 65535, /* Limited by SDMA engine */
52 	.periods_min = 2,
53 	.periods_max = 255,
54 	.fifo_size = 0,
55 };
56 
57 static const struct snd_dmaengine_pcm_config imx_dmaengine_pcm_config = {
58 	.pcm_hardware = &imx_pcm_hardware,
59 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
60 	.compat_filter_fn = filter,
61 	.prealloc_buffer_size = IMX_SSI_DMABUF_SIZE,
62 };
63 
64 int imx_pcm_dma_init(struct platform_device *pdev)
65 {
66 	return snd_dmaengine_pcm_register(&pdev->dev, &imx_dmaengine_pcm_config,
67 		SND_DMAENGINE_PCM_FLAG_NO_RESIDUE |
68 		SND_DMAENGINE_PCM_FLAG_COMPAT);
69 }
70 EXPORT_SYMBOL_GPL(imx_pcm_dma_init);
71 
72 void imx_pcm_dma_exit(struct platform_device *pdev)
73 {
74 	snd_dmaengine_pcm_unregister(&pdev->dev);
75 }
76 EXPORT_SYMBOL_GPL(imx_pcm_dma_exit);
77 
78 MODULE_LICENSE("GPL");
79