xref: /openbmc/linux/sound/soc/pxa/pxa2xx-pcm.c (revision b6bec26c)
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 
16 #include <sound/core.h>
17 #include <sound/soc.h>
18 #include <sound/pxa2xx-lib.h>
19 
20 #include "../../arm/pxa2xx-pcm.h"
21 
22 static int pxa2xx_pcm_hw_params(struct snd_pcm_substream *substream,
23 	struct snd_pcm_hw_params *params)
24 {
25 	struct snd_pcm_runtime *runtime = substream->runtime;
26 	struct pxa2xx_runtime_data *prtd = runtime->private_data;
27 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
28 	struct pxa2xx_pcm_dma_params *dma;
29 	int ret;
30 
31 	dma = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
32 
33 	/* return if this is a bufferless transfer e.g.
34 	 * codec <--> BT codec or GSM modem -- lg FIXME */
35 	if (!dma)
36 		return 0;
37 
38 	/* this may get called several times by oss emulation
39 	 * with different params */
40 	if (prtd->params == NULL) {
41 		prtd->params = dma;
42 		ret = pxa_request_dma(prtd->params->name, DMA_PRIO_LOW,
43 			      pxa2xx_pcm_dma_irq, substream);
44 		if (ret < 0)
45 			return ret;
46 		prtd->dma_ch = ret;
47 	} else if (prtd->params != dma) {
48 		pxa_free_dma(prtd->dma_ch);
49 		prtd->params = dma;
50 		ret = pxa_request_dma(prtd->params->name, DMA_PRIO_LOW,
51 			      pxa2xx_pcm_dma_irq, substream);
52 		if (ret < 0)
53 			return ret;
54 		prtd->dma_ch = ret;
55 	}
56 
57 	return __pxa2xx_pcm_hw_params(substream, params);
58 }
59 
60 static int pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream)
61 {
62 	struct pxa2xx_runtime_data *prtd = substream->runtime->private_data;
63 
64 	__pxa2xx_pcm_hw_free(substream);
65 
66 	if (prtd->dma_ch >= 0) {
67 		pxa_free_dma(prtd->dma_ch);
68 		prtd->dma_ch = -1;
69 		prtd->params = NULL;
70 	}
71 
72 	return 0;
73 }
74 
75 static struct snd_pcm_ops pxa2xx_pcm_ops = {
76 	.open		= __pxa2xx_pcm_open,
77 	.close		= __pxa2xx_pcm_close,
78 	.ioctl		= snd_pcm_lib_ioctl,
79 	.hw_params	= pxa2xx_pcm_hw_params,
80 	.hw_free	= pxa2xx_pcm_hw_free,
81 	.prepare	= __pxa2xx_pcm_prepare,
82 	.trigger	= pxa2xx_pcm_trigger,
83 	.pointer	= pxa2xx_pcm_pointer,
84 	.mmap		= pxa2xx_pcm_mmap,
85 };
86 
87 static u64 pxa2xx_pcm_dmamask = DMA_BIT_MASK(32);
88 
89 static int pxa2xx_soc_pcm_new(struct snd_soc_pcm_runtime *rtd)
90 {
91 	struct snd_card *card = rtd->card->snd_card;
92 	struct snd_pcm *pcm = rtd->pcm;
93 	int ret = 0;
94 
95 	if (!card->dev->dma_mask)
96 		card->dev->dma_mask = &pxa2xx_pcm_dmamask;
97 	if (!card->dev->coherent_dma_mask)
98 		card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
99 
100 	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
101 		ret = pxa2xx_pcm_preallocate_dma_buffer(pcm,
102 			SNDRV_PCM_STREAM_PLAYBACK);
103 		if (ret)
104 			goto out;
105 	}
106 
107 	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
108 		ret = pxa2xx_pcm_preallocate_dma_buffer(pcm,
109 			SNDRV_PCM_STREAM_CAPTURE);
110 		if (ret)
111 			goto out;
112 	}
113  out:
114 	return ret;
115 }
116 
117 static struct snd_soc_platform_driver pxa2xx_soc_platform = {
118 	.ops 	= &pxa2xx_pcm_ops,
119 	.pcm_new	= pxa2xx_soc_pcm_new,
120 	.pcm_free	= pxa2xx_pcm_free_dma_buffers,
121 };
122 
123 static int pxa2xx_soc_platform_probe(struct platform_device *pdev)
124 {
125 	return snd_soc_register_platform(&pdev->dev, &pxa2xx_soc_platform);
126 }
127 
128 static int pxa2xx_soc_platform_remove(struct platform_device *pdev)
129 {
130 	snd_soc_unregister_platform(&pdev->dev);
131 	return 0;
132 }
133 
134 static struct platform_driver pxa_pcm_driver = {
135 	.driver = {
136 			.name = "pxa-pcm-audio",
137 			.owner = THIS_MODULE,
138 	},
139 
140 	.probe = pxa2xx_soc_platform_probe,
141 	.remove = pxa2xx_soc_platform_remove,
142 };
143 
144 module_platform_driver(pxa_pcm_driver);
145 
146 MODULE_AUTHOR("Nicolas Pitre");
147 MODULE_DESCRIPTION("Intel PXA2xx PCM DMA module");
148 MODULE_LICENSE("GPL");
149