sound/soc/spear/spear_pcm.c

   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_soc_pcm_runtime *rtd)
 153 {
 154         struct snd_card *card = rtd->card->snd_card;
 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 (rtd->cpu_dai->driver->playback.channels_min) {
 163                 ret = spear_pcm_preallocate_dma_buffer(rtd->pcm,
 164                                 SNDRV_PCM_STREAM_PLAYBACK,
 165                                 spear_pcm_hardware.buffer_bytes_max);
 166                 if (ret)
 167                         return ret;
 168         }
 169
 170         if (rtd->cpu_dai->driver->capture.channels_min) {
 171                 ret = spear_pcm_preallocate_dma_buffer(rtd->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 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 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 = 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");