xref: /openbmc/linux/sound/soc/pxa/pxa2xx-pcm.c (revision 8684014d)
1 /*
2  * linux/sound/arm/pxa2xx-pcm.c -- ALSA PCM interface for the Intel PXA2xx chip
3  *
4  * Author:	Nicolas Pitre
5  * Created:	Nov 30, 2004
6  * Copyright:	(C) 2004 MontaVista Software, Inc.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  */
12 
13 #include <linux/dma-mapping.h>
14 #include <linux/module.h>
15 #include <linux/dmaengine.h>
16 #include <linux/of.h>
17 
18 #include <mach/dma.h>
19 
20 #include <sound/core.h>
21 #include <sound/soc.h>
22 #include <sound/pxa2xx-lib.h>
23 #include <sound/dmaengine_pcm.h>
24 
25 #include "../../arm/pxa2xx-pcm.h"
26 
27 static int pxa2xx_pcm_hw_params(struct snd_pcm_substream *substream,
28 	struct snd_pcm_hw_params *params)
29 {
30 	struct snd_pcm_runtime *runtime = substream->runtime;
31 	struct pxa2xx_runtime_data *prtd = runtime->private_data;
32 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
33 	struct snd_dmaengine_dai_dma_data *dma;
34 	int ret;
35 
36 	dma = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
37 
38 	/* return if this is a bufferless transfer e.g.
39 	 * codec <--> BT codec or GSM modem -- lg FIXME */
40 	if (!dma)
41 		return 0;
42 
43 	/* this may get called several times by oss emulation
44 	 * with different params */
45 	if (prtd->params == NULL) {
46 		prtd->params = dma;
47 		ret = pxa_request_dma("name", DMA_PRIO_LOW,
48 			      pxa2xx_pcm_dma_irq, substream);
49 		if (ret < 0)
50 			return ret;
51 		prtd->dma_ch = ret;
52 	} else if (prtd->params != dma) {
53 		pxa_free_dma(prtd->dma_ch);
54 		prtd->params = dma;
55 		ret = pxa_request_dma("name", DMA_PRIO_LOW,
56 			      pxa2xx_pcm_dma_irq, substream);
57 		if (ret < 0)
58 			return ret;
59 		prtd->dma_ch = ret;
60 	}
61 
62 	return __pxa2xx_pcm_hw_params(substream, params);
63 }
64 
65 static int pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream)
66 {
67 	struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;
68 
69 	__pxa2xx_pcm_hw_free(substream);
70 
71 	if (prtd->dma_ch >= 0) {
72 		pxa_free_dma(prtd->dma_ch);
73 		prtd->dma_ch = -1;
74 		prtd->params = NULL;
75 	}
76 
77 	return 0;
78 }
79 
80 static struct snd_pcm_ops pxa2xx_pcm_ops = {
81 	.open		= __pxa2xx_pcm_open,
82 	.close		= __pxa2xx_pcm_close,
83 	.ioctl		= snd_pcm_lib_ioctl,
84 	.hw_params	= pxa2xx_pcm_hw_params,
85 	.hw_free	= pxa2xx_pcm_hw_free,
86 	.prepare	= __pxa2xx_pcm_prepare,
87 	.trigger	= pxa2xx_pcm_trigger,
88 	.pointer	= pxa2xx_pcm_pointer,
89 	.mmap		= pxa2xx_pcm_mmap,
90 };
91 
92 static int pxa2xx_soc_pcm_new(struct snd_soc_pcm_runtime *rtd)
93 {
94 	struct snd_card *card = rtd->card->snd_card;
95 	struct snd_pcm *pcm = rtd->pcm;
96 	int ret;
97 
98 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
99 	if (ret)
100 		return ret;
101 
102 	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
103 		ret = pxa2xx_pcm_preallocate_dma_buffer(pcm,
104 			SNDRV_PCM_STREAM_PLAYBACK);
105 		if (ret)
106 			goto out;
107 	}
108 
109 	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
110 		ret = pxa2xx_pcm_preallocate_dma_buffer(pcm,
111 			SNDRV_PCM_STREAM_CAPTURE);
112 		if (ret)
113 			goto out;
114 	}
115  out:
116 	return ret;
117 }
118 
119 static struct snd_soc_platform_driver pxa2xx_soc_platform = {
120 	.ops 	= &pxa2xx_pcm_ops,
121 	.pcm_new	= pxa2xx_soc_pcm_new,
122 	.pcm_free	= pxa2xx_pcm_free_dma_buffers,
123 };
124 
125 static int pxa2xx_soc_platform_probe(struct platform_device *pdev)
126 {
127 	return snd_soc_register_platform(&pdev->dev, &pxa2xx_soc_platform);
128 }
129 
130 static int pxa2xx_soc_platform_remove(struct platform_device *pdev)
131 {
132 	snd_soc_unregister_platform(&pdev->dev);
133 	return 0;
134 }
135 
136 #ifdef CONFIG_OF
137 static const struct of_device_id snd_soc_pxa_audio_match[] = {
138 	{ .compatible   = "mrvl,pxa-pcm-audio" },
139 	{ }
140 };
141 #endif
142 
143 static struct platform_driver pxa_pcm_driver = {
144 	.driver = {
145 		.name = "pxa-pcm-audio",
146 		.of_match_table = of_match_ptr(snd_soc_pxa_audio_match),
147 	},
148 
149 	.probe = pxa2xx_soc_platform_probe,
150 	.remove = pxa2xx_soc_platform_remove,
151 };
152 
153 module_platform_driver(pxa_pcm_driver);
154 
155 MODULE_AUTHOR("Nicolas Pitre");
156 MODULE_DESCRIPTION("Intel PXA2xx PCM DMA module");
157 MODULE_LICENSE("GPL");
158