xref: /openbmc/linux/sound/soc/spear/spear_pcm.c (revision e23feb16)
1 /*
2  * ALSA PCM interface for ST SPEAr Processors
3  *
4  * sound/soc/spear/spear_pcm.c
5  *
6  * Copyright (C) 2012 ST Microelectronics
7  * Rajeev Kumar<rajeev-dlh.kumar@st.com>
8  *
9  * This file is licensed under the terms of the GNU General Public
10  * License version 2. This program is licensed "as is" without any
11  * warranty of any kind, whether express or implied.
12  */
13 
14 #include <linux/module.h>
15 #include <linux/dmaengine.h>
16 #include <linux/platform_device.h>
17 #include <sound/dmaengine_pcm.h>
18 #include <sound/pcm.h>
19 #include <sound/soc.h>
20 #include <sound/spear_dma.h>
21 
22 static const struct snd_pcm_hardware spear_pcm_hardware = {
23 	.info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
24 		 SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
25 		 SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME),
26 	.buffer_bytes_max = 16 * 1024, /* max buffer size */
27 	.period_bytes_min = 2 * 1024, /* 1 msec data minimum period size */
28 	.period_bytes_max = 2 * 1024, /* maximum period size */
29 	.periods_min = 1, /* min # periods */
30 	.periods_max = 8, /* max # of periods */
31 	.fifo_size = 0, /* fifo size in bytes */
32 };
33 
34 static struct dma_chan *spear_pcm_request_chan(struct snd_soc_pcm_runtime *rtd,
35 	struct snd_pcm_substream *substream)
36 {
37 	struct spear_dma_data *dma_data;
38 
39 	dma_data = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
40 
41 	return snd_dmaengine_pcm_request_channel(dma_data->filter, dma_data);
42 }
43 
44 static const struct snd_dmaengine_pcm_config spear_dmaengine_pcm_config = {
45 	.pcm_hardware = &spear_pcm_hardware,
46 	.compat_request_channel = spear_pcm_request_chan,
47 	.prealloc_buffer_size = 16 * 1024,
48 };
49 
50 static int spear_soc_platform_probe(struct platform_device *pdev)
51 {
52 	return snd_dmaengine_pcm_register(&pdev->dev,
53 		&spear_dmaengine_pcm_config,
54 		SND_DMAENGINE_PCM_FLAG_NO_DT |
55 		SND_DMAENGINE_PCM_FLAG_COMPAT);
56 }
57 
58 static int spear_soc_platform_remove(struct platform_device *pdev)
59 {
60 	snd_dmaengine_pcm_unregister(&pdev->dev);
61 	return 0;
62 }
63 
64 static struct platform_driver spear_pcm_driver = {
65 	.driver = {
66 		.name = "spear-pcm-audio",
67 		.owner = THIS_MODULE,
68 	},
69 
70 	.probe = spear_soc_platform_probe,
71 	.remove = spear_soc_platform_remove,
72 };
73 
74 module_platform_driver(spear_pcm_driver);
75 
76 MODULE_AUTHOR("Rajeev Kumar <rajeev-dlh.kumar@st.com>");
77 MODULE_DESCRIPTION("SPEAr PCM DMA module");
78 MODULE_LICENSE("GPL");
79 MODULE_ALIAS("platform:spear-pcm-audio");
80