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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 
filter(struct dma_chan * chan,void * param)26 static bool filter(struct dma_chan *chan, void *param)
27 {
28 	if (!imx_dma_is_general_purpose(chan))
29 		return false;
30 
31 	chan->private = param;
32 
33 	return true;
34 }
35 
36 static const struct snd_pcm_hardware imx_pcm_hardware = {
37 	.info = SNDRV_PCM_INFO_INTERLEAVED |
38 		SNDRV_PCM_INFO_BLOCK_TRANSFER |
39 		SNDRV_PCM_INFO_MMAP |
40 		SNDRV_PCM_INFO_MMAP_VALID |
41 		SNDRV_PCM_INFO_PAUSE |
42 		SNDRV_PCM_INFO_RESUME,
43 	.buffer_bytes_max = IMX_DEFAULT_DMABUF_SIZE,
44 	.period_bytes_min = 128,
45 	.period_bytes_max = 65535, /* Limited by SDMA engine */
46 	.periods_min = 2,
47 	.periods_max = 255,
48 	.fifo_size = 0,
49 };
50 
51 static const struct snd_dmaengine_pcm_config imx_dmaengine_pcm_config = {
52 	.pcm_hardware = &imx_pcm_hardware,
53 	.prepare_slave_config = snd_dmaengine_pcm_prepare_slave_config,
54 	.compat_filter_fn = filter,
55 	.prealloc_buffer_size = IMX_DEFAULT_DMABUF_SIZE,
56 };
57 
imx_pcm_dma_init(struct platform_device * pdev,size_t size)58 int imx_pcm_dma_init(struct platform_device *pdev, size_t size)
59 {
60 	struct snd_dmaengine_pcm_config *config;
61 	struct snd_pcm_hardware *pcm_hardware;
62 
63 	config = devm_kzalloc(&pdev->dev,
64 			sizeof(struct snd_dmaengine_pcm_config), GFP_KERNEL);
65 	if (!config)
66 		return -ENOMEM;
67 	*config = imx_dmaengine_pcm_config;
68 	if (size)
69 		config->prealloc_buffer_size = size;
70 
71 	pcm_hardware = devm_kzalloc(&pdev->dev,
72 			sizeof(struct snd_pcm_hardware), GFP_KERNEL);
73 	*pcm_hardware = imx_pcm_hardware;
74 	if (size)
75 		pcm_hardware->buffer_bytes_max = size;
76 
77 	config->pcm_hardware = pcm_hardware;
78 
79 	return devm_snd_dmaengine_pcm_register(&pdev->dev,
80 		config,
81 		SND_DMAENGINE_PCM_FLAG_COMPAT);
82 }
83 EXPORT_SYMBOL_GPL(imx_pcm_dma_init);
84 
85 MODULE_LICENSE("GPL");
86