sound/soc/au1x/dma.c

   1 /*
   2  * Au1000/Au1500/Au1100 Audio DMA support.
   3  *
   4  * (c) 2011 Manuel Lauss <manuel.lauss@googlemail.com>
   5  *
   6  * copied almost verbatim from the old ALSA driver, written by
   7  *                      Charles Eidsness <charles@cooper-street.com>
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/init.h>
  12 #include <linux/platform_device.h>
  13 #include <linux/slab.h>
  14 #include <linux/dma-mapping.h>
  15 #include <sound/core.h>
  16 #include <sound/pcm.h>
  17 #include <sound/pcm_params.h>
  18 #include <sound/soc.h>
  19 #include <asm/mach-au1x00/au1000.h>
  20 #include <asm/mach-au1x00/au1000_dma.h>
  21
  22 #include "psc.h"
  23
  24 #define ALCHEMY_PCM_FMTS                                        \
  25         (SNDRV_PCM_FMTBIT_S8     | SNDRV_PCM_FMTBIT_U8 |        \
  26          SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S16_BE |    \
  27          SNDRV_PCM_FMTBIT_U16_LE | SNDRV_PCM_FMTBIT_U16_BE |    \
  28          SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S32_BE |    \
  29          SNDRV_PCM_FMTBIT_U32_LE | SNDRV_PCM_FMTBIT_U32_BE |    \
  30          0)
  31
  32 struct pcm_period {
  33         u32 start;
  34         u32 relative_end;       /* relative to start of buffer */
  35         struct pcm_period *next;
  36 };
  37
  38 struct audio_stream {
  39         struct snd_pcm_substream *substream;
  40         int dma;
  41         struct pcm_period *buffer;
  42         unsigned int period_size;
  43         unsigned int periods;
  44 };
  45
  46 struct alchemy_pcm_ctx {
  47         struct audio_stream stream[2];  /* playback & capture */
  48 };
  49
  50 static void au1000_release_dma_link(struct audio_stream *stream)
  51 {
  52         struct pcm_period *pointer;
  53         struct pcm_period *pointer_next;
  54
  55         stream->period_size = 0;
  56         stream->periods = 0;
  57         pointer = stream->buffer;
  58         if (!pointer)
  59                 return;
  60         do {
  61                 pointer_next = pointer->next;
  62                 kfree(pointer);
  63                 pointer = pointer_next;
  64         } while (pointer != stream->buffer);
  65         stream->buffer = NULL;
  66 }
  67
  68 static int au1000_setup_dma_link(struct audio_stream *stream,
  69                                  unsigned int period_bytes,
  70                                  unsigned int periods)
  71 {
  72         struct snd_pcm_substream *substream = stream->substream;
  73         struct snd_pcm_runtime *runtime = substream->runtime;
  74         struct pcm_period *pointer;
  75         unsigned long dma_start;
  76         int i;
  77
  78         dma_start = virt_to_phys(runtime->dma_area);
  79
  80         if (stream->period_size == period_bytes &&
  81             stream->periods == periods)
  82                 return 0; /* not changed */
  83
  84         au1000_release_dma_link(stream);
  85
  86         stream->period_size = period_bytes;
  87         stream->periods = periods;
  88
  89         stream->buffer = kmalloc(sizeof(struct pcm_period), GFP_KERNEL);
  90         if (!stream->buffer)
  91                 return -ENOMEM;
  92         pointer = stream->buffer;
  93         for (i = 0; i < periods; i++) {
  94                 pointer->start = (u32)(dma_start + (i * period_bytes));
  95                 pointer->relative_end = (u32) (((i+1) * period_bytes) - 0x1);
  96                 if (i < periods - 1) {
  97                         pointer->next = kmalloc(sizeof(struct pcm_period),
  98                                                 GFP_KERNEL);
  99                         if (!pointer->next) {
 100                                 au1000_release_dma_link(stream);
 101                                 return -ENOMEM;
 102                         }
 103                         pointer = pointer->next;
 104                 }
 105         }
 106         pointer->next = stream->buffer;
 107         return 0;
 108 }
 109
 110 static void au1000_dma_stop(struct audio_stream *stream)
 111 {
 112         if (stream->buffer)
 113                 disable_dma(stream->dma);
 114 }
 115
 116 static void au1000_dma_start(struct audio_stream *stream)
 117 {
 118         if (!stream->buffer)
 119                 return;
 120
 121         init_dma(stream->dma);
 122         if (get_dma_active_buffer(stream->dma) == 0) {
 123                 clear_dma_done0(stream->dma);
 124                 set_dma_addr0(stream->dma, stream->buffer->start);
 125                 set_dma_count0(stream->dma, stream->period_size >> 1);
 126                 set_dma_addr1(stream->dma, stream->buffer->next->start);
 127                 set_dma_count1(stream->dma, stream->period_size >> 1);
 128         } else {
 129                 clear_dma_done1(stream->dma);
 130                 set_dma_addr1(stream->dma, stream->buffer->start);
 131                 set_dma_count1(stream->dma, stream->period_size >> 1);
 132                 set_dma_addr0(stream->dma, stream->buffer->next->start);
 133                 set_dma_count0(stream->dma, stream->period_size >> 1);
 134         }
 135         enable_dma_buffers(stream->dma);
 136         start_dma(stream->dma);
 137 }
 138
 139 static irqreturn_t au1000_dma_interrupt(int irq, void *ptr)
 140 {
 141         struct audio_stream *stream = (struct audio_stream *)ptr;
 142         struct snd_pcm_substream *substream = stream->substream;
 143
 144         switch (get_dma_buffer_done(stream->dma)) {
 145         case DMA_D0:
 146                 stream->buffer = stream->buffer->next;
 147                 clear_dma_done0(stream->dma);
 148                 set_dma_addr0(stream->dma, stream->buffer->next->start);
 149                 set_dma_count0(stream->dma, stream->period_size >> 1);
 150                 enable_dma_buffer0(stream->dma);
 151                 break;
 152         case DMA_D1:
 153                 stream->buffer = stream->buffer->next;
 154                 clear_dma_done1(stream->dma);
 155                 set_dma_addr1(stream->dma, stream->buffer->next->start);
 156                 set_dma_count1(stream->dma, stream->period_size >> 1);
 157                 enable_dma_buffer1(stream->dma);
 158                 break;
 159         case (DMA_D0 | DMA_D1):
 160                 pr_debug("DMA %d missed interrupt.\n", stream->dma);
 161                 au1000_dma_stop(stream);
 162                 au1000_dma_start(stream);
 163                 break;
 164         case (~DMA_D0 & ~DMA_D1):
 165                 pr_debug("DMA %d empty irq.\n", stream->dma);
 166         }
 167         snd_pcm_period_elapsed(substream);
 168         return IRQ_HANDLED;
 169 }
 170
 171 static const struct snd_pcm_hardware alchemy_pcm_hardware = {
 172         .info             = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
 173                             SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BATCH,
 174         .formats          = ALCHEMY_PCM_FMTS,
 175         .rates            = SNDRV_PCM_RATE_8000_192000,
 176         .rate_min         = SNDRV_PCM_RATE_8000,
 177         .rate_max         = SNDRV_PCM_RATE_192000,
 178         .channels_min     = 2,
 179         .channels_max     = 2,
 180         .period_bytes_min = 1024,
 181         .period_bytes_max = 16 * 1024 - 1,
 182         .periods_min      = 4,
 183         .periods_max      = 255,
 184         .buffer_bytes_max = 128 * 1024,
 185         .fifo_size        = 16,
 186 };
 187
 188 static inline struct alchemy_pcm_ctx *ss_to_ctx(struct snd_pcm_substream *ss)
 189 {
 190         struct snd_soc_pcm_runtime *rtd = ss->private_data;
 191         return snd_soc_platform_get_drvdata(rtd->platform);
 192 }
 193
 194 static inline struct audio_stream *ss_to_as(struct snd_pcm_substream *ss)
 195 {
 196         struct alchemy_pcm_ctx *ctx = ss_to_ctx(ss);
 197         return &(ctx->stream[ss->stream]);
 198 }
 199
 200 static int alchemy_pcm_open(struct snd_pcm_substream *substream)
 201 {
 202         struct alchemy_pcm_ctx *ctx = ss_to_ctx(substream);
 203         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 204         int *dmaids, s = substream->stream;
 205         char *name;
 206
 207         dmaids = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 208         if (!dmaids)
 209                 return -ENODEV; /* whoa, has ordering changed? */
 210
 211         /* DMA setup */
 212         name = (s == SNDRV_PCM_STREAM_PLAYBACK) ? "audio-tx" : "audio-rx";
 213         ctx->stream[s].dma = request_au1000_dma(dmaids[s], name,
 214                                         au1000_dma_interrupt, 0,
 215                                         &ctx->stream[s]);
 216         set_dma_mode(ctx->stream[s].dma,
 217                      get_dma_mode(ctx->stream[s].dma) & ~DMA_NC);
 218
 219         ctx->stream[s].substream = substream;
 220         ctx->stream[s].buffer = NULL;
 221         snd_soc_set_runtime_hwparams(substream, &alchemy_pcm_hardware);
 222
 223         return 0;
 224 }
 225
 226 static int alchemy_pcm_close(struct snd_pcm_substream *substream)
 227 {
 228         struct alchemy_pcm_ctx *ctx = ss_to_ctx(substream);
 229         int stype = substream->stream;
 230
 231         ctx->stream[stype].substream = NULL;
 232         free_au1000_dma(ctx->stream[stype].dma);
 233
 234         return 0;
 235 }
 236
 237 static int alchemy_pcm_hw_params(struct snd_pcm_substream *substream,
 238                                  struct snd_pcm_hw_params *hw_params)
 239 {
 240         struct audio_stream *stream = ss_to_as(substream);
 241         int err;
 242
 243         err = snd_pcm_lib_malloc_pages(substream,
 244                                        params_buffer_bytes(hw_params));
 245         if (err < 0)
 246                 return err;
 247         err = au1000_setup_dma_link(stream,
 248                                     params_period_bytes(hw_params),
 249                                     params_periods(hw_params));
 250         if (err)
 251                 snd_pcm_lib_free_pages(substream);
 252
 253         return err;
 254 }
 255
 256 static int alchemy_pcm_hw_free(struct snd_pcm_substream *substream)
 257 {
 258         struct audio_stream *stream = ss_to_as(substream);
 259         au1000_release_dma_link(stream);
 260         return snd_pcm_lib_free_pages(substream);
 261 }
 262
 263 static int alchemy_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 264 {
 265         struct audio_stream *stream = ss_to_as(substream);
 266         int err = 0;
 267
 268         switch (cmd) {
 269         case SNDRV_PCM_TRIGGER_START:
 270                 au1000_dma_start(stream);
 271                 break;
 272         case SNDRV_PCM_TRIGGER_STOP:
 273                 au1000_dma_stop(stream);
 274                 break;
 275         default:
 276                 err = -EINVAL;
 277                 break;
 278         }
 279         return err;
 280 }
 281
 282 static snd_pcm_uframes_t alchemy_pcm_pointer(struct snd_pcm_substream *ss)
 283 {
 284         struct audio_stream *stream = ss_to_as(ss);
 285         long location;
 286
 287         location = get_dma_residue(stream->dma);
 288         location = stream->buffer->relative_end - location;
 289         if (location == -1)
 290                 location = 0;
 291         return bytes_to_frames(ss->runtime, location);
 292 }
 293
 294 static struct snd_pcm_ops alchemy_pcm_ops = {
 295         .open                   = alchemy_pcm_open,
 296         .close                  = alchemy_pcm_close,
 297         .ioctl                  = snd_pcm_lib_ioctl,
 298         .hw_params              = alchemy_pcm_hw_params,
 299         .hw_free                = alchemy_pcm_hw_free,
 300         .trigger                = alchemy_pcm_trigger,
 301         .pointer                = alchemy_pcm_pointer,
 302 };
 303
 304 static void alchemy_pcm_free_dma_buffers(struct snd_pcm *pcm)
 305 {
 306         snd_pcm_lib_preallocate_free_for_all(pcm);
 307 }
 308
 309 static int alchemy_pcm_new(struct snd_soc_pcm_runtime *rtd)
 310 {
 311         struct snd_pcm *pcm = rtd->pcm;
 312
 313         snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_CONTINUOUS,
 314                 snd_dma_continuous_data(GFP_KERNEL), 65536, (4096 * 1024) - 1);
 315
 316         return 0;
 317 }
 318
 319 static struct snd_soc_platform_driver alchemy_pcm_soc_platform = {
 320         .ops            = &alchemy_pcm_ops,
 321         .pcm_new        = alchemy_pcm_new,
 322         .pcm_free       = alchemy_pcm_free_dma_buffers,
 323 };
 324
 325 static int __devinit alchemy_pcm_drvprobe(struct platform_device *pdev)
 326 {
 327         struct alchemy_pcm_ctx *ctx;
 328
 329         ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL);
 330         if (!ctx)
 331                 return -ENOMEM;
 332
 333         platform_set_drvdata(pdev, ctx);
 334
 335         return snd_soc_register_platform(&pdev->dev, &alchemy_pcm_soc_platform);
 336 }
 337
 338 static int __devexit alchemy_pcm_drvremove(struct platform_device *pdev)
 339 {
 340         snd_soc_unregister_platform(&pdev->dev);
 341
 342         return 0;
 343 }
 344
 345 static struct platform_driver alchemy_pcmdma_driver = {
 346         .driver = {
 347                 .name   = "alchemy-pcm-dma",
 348                 .owner  = THIS_MODULE,
 349         },
 350         .probe          = alchemy_pcm_drvprobe,
 351         .remove         = __devexit_p(alchemy_pcm_drvremove),
 352 };
 353
 354 module_platform_driver(alchemy_pcmdma_driver);
 355
 356 MODULE_LICENSE("GPL");
 357 MODULE_DESCRIPTION("Au1000/Au1500/Au1100 Audio DMA driver");
 358 MODULE_AUTHOR("Manuel Lauss");