xref: /openbmc/linux/sound/soc/spear/spear_pcm.c (revision 95e9fd10)
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/dma-mapping.h>
17 #include <linux/init.h>
18 #include <linux/platform_device.h>
19 #include <linux/scatterlist.h>
20 #include <linux/slab.h>
21 #include <sound/core.h>
22 #include <sound/dmaengine_pcm.h>
23 #include <sound/pcm.h>
24 #include <sound/pcm_params.h>
25 #include <sound/soc.h>
26 #include <sound/spear_dma.h>
27 
28 struct snd_pcm_hardware spear_pcm_hardware = {
29 	.info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
30 		 SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
31 		 SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME),
32 	.buffer_bytes_max = 16 * 1024, /* max buffer size */
33 	.period_bytes_min = 2 * 1024, /* 1 msec data minimum period size */
34 	.period_bytes_max = 2 * 1024, /* maximum period size */
35 	.periods_min = 1, /* min # periods */
36 	.periods_max = 8, /* max # of periods */
37 	.fifo_size = 0, /* fifo size in bytes */
38 };
39 
40 static int spear_pcm_hw_params(struct snd_pcm_substream *substream,
41 		struct snd_pcm_hw_params *params)
42 {
43 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
44 
45 	return 0;
46 }
47 
48 static int spear_pcm_hw_free(struct snd_pcm_substream *substream)
49 {
50 	snd_pcm_set_runtime_buffer(substream, NULL);
51 
52 	return 0;
53 }
54 
55 static int spear_pcm_open(struct snd_pcm_substream *substream)
56 {
57 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
58 
59 	struct spear_dma_data *dma_data = (struct spear_dma_data *)
60 		snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
61 	int ret;
62 
63 	ret = snd_soc_set_runtime_hwparams(substream, &spear_pcm_hardware);
64 	if (ret)
65 		return ret;
66 
67 	ret = snd_dmaengine_pcm_open(substream, dma_data->filter, dma_data);
68 	if (ret)
69 		return ret;
70 
71 	snd_dmaengine_pcm_set_data(substream, dma_data);
72 
73 	return 0;
74 }
75 
76 static int spear_pcm_close(struct snd_pcm_substream *substream)
77 {
78 
79 	snd_dmaengine_pcm_close(substream);
80 
81 	return 0;
82 }
83 
84 static int spear_pcm_mmap(struct snd_pcm_substream *substream,
85 		struct vm_area_struct *vma)
86 {
87 	struct snd_pcm_runtime *runtime = substream->runtime;
88 
89 	return dma_mmap_writecombine(substream->pcm->card->dev, vma,
90 			runtime->dma_area, runtime->dma_addr,
91 			runtime->dma_bytes);
92 }
93 
94 static struct snd_pcm_ops spear_pcm_ops = {
95 	.open		= spear_pcm_open,
96 	.close		= spear_pcm_close,
97 	.ioctl		= snd_pcm_lib_ioctl,
98 	.hw_params	= spear_pcm_hw_params,
99 	.hw_free	= spear_pcm_hw_free,
100 	.trigger	= snd_dmaengine_pcm_trigger,
101 	.pointer	= snd_dmaengine_pcm_pointer,
102 	.mmap		= spear_pcm_mmap,
103 };
104 
105 static int
106 spear_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream,
107 		size_t size)
108 {
109 	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
110 	struct snd_dma_buffer *buf = &substream->dma_buffer;
111 
112 	buf->dev.type = SNDRV_DMA_TYPE_DEV;
113 	buf->dev.dev = pcm->card->dev;
114 	buf->private_data = NULL;
115 
116 	buf->area = dma_alloc_writecombine(pcm->card->dev, size,
117 			&buf->addr, GFP_KERNEL);
118 	if (!buf->area)
119 		return -ENOMEM;
120 
121 	dev_info(buf->dev.dev,
122 			" preallocate_dma_buffer: area=%p, addr=%p, size=%d\n",
123 			(void *)buf->area, (void *)buf->addr, size);
124 
125 	buf->bytes = size;
126 	return 0;
127 }
128 
129 static void spear_pcm_free(struct snd_pcm *pcm)
130 {
131 	struct snd_pcm_substream *substream;
132 	struct snd_dma_buffer *buf;
133 	int stream;
134 
135 	for (stream = 0; stream < 2; stream++) {
136 		substream = pcm->streams[stream].substream;
137 		if (!substream)
138 			continue;
139 
140 		buf = &substream->dma_buffer;
141 		if (!buf && !buf->area)
142 			continue;
143 
144 		dma_free_writecombine(pcm->card->dev, buf->bytes,
145 				buf->area, buf->addr);
146 		buf->area = NULL;
147 	}
148 }
149 
150 static u64 spear_pcm_dmamask = DMA_BIT_MASK(32);
151 
152 static int spear_pcm_new(struct snd_card *card,
153 		struct snd_soc_dai *dai, struct snd_pcm *pcm)
154 {
155 	int ret;
156 
157 	if (!card->dev->dma_mask)
158 		card->dev->dma_mask = &spear_pcm_dmamask;
159 	if (!card->dev->coherent_dma_mask)
160 		card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
161 
162 	if (dai->driver->playback.channels_min) {
163 		ret = spear_pcm_preallocate_dma_buffer(pcm,
164 				SNDRV_PCM_STREAM_PLAYBACK,
165 				spear_pcm_hardware.buffer_bytes_max);
166 		if (ret)
167 			return ret;
168 	}
169 
170 	if (dai->driver->capture.channels_min) {
171 		ret = spear_pcm_preallocate_dma_buffer(pcm,
172 				SNDRV_PCM_STREAM_CAPTURE,
173 				spear_pcm_hardware.buffer_bytes_max);
174 		if (ret)
175 			return ret;
176 	}
177 
178 	return 0;
179 }
180 
181 struct snd_soc_platform_driver spear_soc_platform = {
182 	.ops		=	&spear_pcm_ops,
183 	.pcm_new	=	spear_pcm_new,
184 	.pcm_free	=	spear_pcm_free,
185 };
186 
187 static int __devinit spear_soc_platform_probe(struct platform_device *pdev)
188 {
189 	return snd_soc_register_platform(&pdev->dev, &spear_soc_platform);
190 }
191 
192 static int __devexit spear_soc_platform_remove(struct platform_device *pdev)
193 {
194 	snd_soc_unregister_platform(&pdev->dev);
195 
196 	return 0;
197 }
198 
199 static struct platform_driver spear_pcm_driver = {
200 	.driver = {
201 		.name = "spear-pcm-audio",
202 		.owner = THIS_MODULE,
203 	},
204 
205 	.probe = spear_soc_platform_probe,
206 	.remove = __devexit_p(spear_soc_platform_remove),
207 };
208 
209 module_platform_driver(spear_pcm_driver);
210 
211 MODULE_AUTHOR("Rajeev Kumar <rajeev-dlh.kumar@st.com>");
212 MODULE_DESCRIPTION("SPEAr PCM DMA module");
213 MODULE_LICENSE("GPL");
214 MODULE_ALIAS("platform:spear-pcm-audio");
215