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         return snd_dmaengine_pcm_open(substream, dma_data->filter, dma_data)
  68 }
  69
  70 static int spear_pcm_mmap(struct snd_pcm_substream *substream,
  71                 struct vm_area_struct *vma)
  72 {
  73         struct snd_pcm_runtime *runtime = substream->runtime;
  74
  75         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
  76                         runtime->dma_area, runtime->dma_addr,
  77                         runtime->dma_bytes);
  78 }
  79
  80 static struct snd_pcm_ops spear_pcm_ops = {
  81         .open           = spear_pcm_open,
  82         .close          = snd_dmaengine_pcm_close,
  83         .ioctl          = snd_pcm_lib_ioctl,
  84         .hw_params      = spear_pcm_hw_params,
  85         .hw_free        = spear_pcm_hw_free,
  86         .trigger        = snd_dmaengine_pcm_trigger,
  87         .pointer        = snd_dmaengine_pcm_pointer,
  88         .mmap           = spear_pcm_mmap,
  89 };
  90
  91 static int
  92 spear_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream,
  93                 size_t size)
  94 {
  95         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
  96         struct snd_dma_buffer *buf = &substream->dma_buffer;
  97
  98         buf->dev.type = SNDRV_DMA_TYPE_DEV;
  99         buf->dev.dev = pcm->card->dev;
 100         buf->private_data = NULL;
 101
 102         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 103                         &buf->addr, GFP_KERNEL);
 104         if (!buf->area)
 105                 return -ENOMEM;
 106
 107         dev_info(buf->dev.dev,
 108                         " preallocate_dma_buffer: area=%p, addr=%p, size=%d\n",
 109                         (void *)buf->area, (void *)buf->addr, size);
 110
 111         buf->bytes = size;
 112         return 0;
 113 }
 114
 115 static void spear_pcm_free(struct snd_pcm *pcm)
 116 {
 117         struct snd_pcm_substream *substream;
 118         struct snd_dma_buffer *buf;
 119         int stream;
 120
 121         for (stream = 0; stream < 2; stream++) {
 122                 substream = pcm->streams[stream].substream;
 123                 if (!substream)
 124                         continue;
 125
 126                 buf = &substream->dma_buffer;
 127                 if (!buf || !buf->area)
 128                         continue;
 129
 130                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 131                                 buf->area, buf->addr);
 132                 buf->area = NULL;
 133         }
 134 }
 135
 136 static u64 spear_pcm_dmamask = DMA_BIT_MASK(32);
 137
 138 static int spear_pcm_new(struct snd_card *card,
 139                 struct snd_soc_dai *dai, struct snd_pcm *pcm)
 140 {
 141         int ret;
 142
 143         if (!card->dev->dma_mask)
 144                 card->dev->dma_mask = &spear_pcm_dmamask;
 145         if (!card->dev->coherent_dma_mask)
 146                 card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
 147
 148         if (dai->driver->playback.channels_min) {
 149                 ret = spear_pcm_preallocate_dma_buffer(pcm,
 150                                 SNDRV_PCM_STREAM_PLAYBACK,
 151                                 spear_pcm_hardware.buffer_bytes_max);
 152                 if (ret)
 153                         return ret;
 154         }
 155
 156         if (dai->driver->capture.channels_min) {
 157                 ret = spear_pcm_preallocate_dma_buffer(pcm,
 158                                 SNDRV_PCM_STREAM_CAPTURE,
 159                                 spear_pcm_hardware.buffer_bytes_max);
 160                 if (ret)
 161                         return ret;
 162         }
 163
 164         return 0;
 165 }
 166
 167 struct snd_soc_platform_driver spear_soc_platform = {
 168         .ops            =       &spear_pcm_ops,
 169         .pcm_new        =       spear_pcm_new,
 170         .pcm_free       =       spear_pcm_free,
 171 };
 172
 173 static int spear_soc_platform_probe(struct platform_device *pdev)
 174 {
 175         return snd_soc_register_platform(&pdev->dev, &spear_soc_platform);
 176 }
 177
 178 static int spear_soc_platform_remove(struct platform_device *pdev)
 179 {
 180         snd_soc_unregister_platform(&pdev->dev);
 181
 182         return 0;
 183 }
 184
 185 static struct platform_driver spear_pcm_driver = {
 186         .driver = {
 187                 .name = "spear-pcm-audio",
 188                 .owner = THIS_MODULE,
 189         },
 190
 191         .probe = spear_soc_platform_probe,
 192         .remove = spear_soc_platform_remove,
 193 };
 194
 195 module_platform_driver(spear_pcm_driver);
 196
 197 MODULE_AUTHOR("Rajeev Kumar <rajeev-dlh.kumar@st.com>");
 198 MODULE_DESCRIPTION("SPEAr PCM DMA module");
 199 MODULE_LICENSE("GPL");
 200 MODULE_ALIAS("platform:spear-pcm-audio");