sound/soc/samsung/dma.c

   1 /*
   2  * dma.c  --  ALSA Soc Audio Layer
   3  *
   4  * (c) 2006 Wolfson Microelectronics PLC.
   5  * Graeme Gregory graeme.gregory@wolfsonmicro.com or linux@wolfsonmicro.com
   6  *
   7  * Copyright 2004-2005 Simtec Electronics
   8  *      http://armlinux.simtec.co.uk/
   9  *      Ben Dooks <ben@simtec.co.uk>
  10  *
  11  *  This program is free software; you can redistribute  it and/or modify it
  12  *  under  the terms of  the GNU General  Public License as published by the
  13  *  Free Software Foundation;  either version 2 of the  License, or (at your
  14  *  option) any later version.
  15  */
  16
  17 #include <linux/slab.h>
  18 #include <linux/dma-mapping.h>
  19
  20 #include <sound/soc.h>
  21 #include <sound/pcm_params.h>
  22
  23 #include <asm/dma.h>
  24 #include <mach/hardware.h>
  25 #include <mach/dma.h>
  26
  27 #include "dma.h"
  28
  29 #define ST_RUNNING              (1<<0)
  30 #define ST_OPENED               (1<<1)
  31
  32 static const struct snd_pcm_hardware dma_hardware = {
  33         .info                   = SNDRV_PCM_INFO_INTERLEAVED |
  34                                     SNDRV_PCM_INFO_BLOCK_TRANSFER |
  35                                     SNDRV_PCM_INFO_MMAP |
  36                                     SNDRV_PCM_INFO_MMAP_VALID |
  37                                     SNDRV_PCM_INFO_PAUSE |
  38                                     SNDRV_PCM_INFO_RESUME,
  39         .formats                = SNDRV_PCM_FMTBIT_S16_LE |
  40                                     SNDRV_PCM_FMTBIT_U16_LE |
  41                                     SNDRV_PCM_FMTBIT_U8 |
  42                                     SNDRV_PCM_FMTBIT_S8,
  43         .channels_min           = 2,
  44         .channels_max           = 2,
  45         .buffer_bytes_max       = 128*1024,
  46         .period_bytes_min       = PAGE_SIZE,
  47         .period_bytes_max       = PAGE_SIZE*2,
  48         .periods_min            = 2,
  49         .periods_max            = 128,
  50         .fifo_size              = 32,
  51 };
  52
  53 struct runtime_data {
  54         spinlock_t lock;
  55         int state;
  56         unsigned int dma_loaded;
  57         unsigned int dma_period;
  58         dma_addr_t dma_start;
  59         dma_addr_t dma_pos;
  60         dma_addr_t dma_end;
  61         struct s3c_dma_params *params;
  62 };
  63
  64 static void audio_buffdone(void *data);
  65
  66 /* dma_enqueue
  67  *
  68  * place a dma buffer onto the queue for the dma system
  69  * to handle.
  70  */
  71 static void dma_enqueue(struct snd_pcm_substream *substream)
  72 {
  73         struct runtime_data *prtd = substream->runtime->private_data;
  74         dma_addr_t pos = prtd->dma_pos;
  75         unsigned int limit;
  76         struct samsung_dma_prep_info dma_info;
  77
  78         pr_debug("Entered %s\n", __func__);
  79
  80         limit = (prtd->dma_end - prtd->dma_start) / prtd->dma_period;
  81
  82         pr_debug("%s: loaded %d, limit %d\n",
  83                                 __func__, prtd->dma_loaded, limit);
  84
  85         dma_info.cap = (samsung_dma_has_circular() ? DMA_CYCLIC : DMA_SLAVE);
  86         dma_info.direction =
  87                 (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
  88                 ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
  89         dma_info.fp = audio_buffdone;
  90         dma_info.fp_param = substream;
  91         dma_info.period = prtd->dma_period;
  92         dma_info.len = prtd->dma_period*limit;
  93
  94         while (prtd->dma_loaded < limit) {
  95                 pr_debug("dma_loaded: %d\n", prtd->dma_loaded);
  96
  97                 if ((pos + dma_info.period) > prtd->dma_end) {
  98                         dma_info.period  = prtd->dma_end - pos;
  99                         pr_debug("%s: corrected dma len %ld\n",
 100                                         __func__, dma_info.period);
 101                 }
 102
 103                 dma_info.buf = pos;
 104                 prtd->params->ops->prepare(prtd->params->ch, &dma_info);
 105
 106                 prtd->dma_loaded++;
 107                 pos += prtd->dma_period;
 108                 if (pos >= prtd->dma_end)
 109                         pos = prtd->dma_start;
 110         }
 111
 112         prtd->dma_pos = pos;
 113 }
 114
 115 static void audio_buffdone(void *data)
 116 {
 117         struct snd_pcm_substream *substream = data;
 118         struct runtime_data *prtd = substream->runtime->private_data;
 119
 120         pr_debug("Entered %s\n", __func__);
 121
 122         if (prtd->state & ST_RUNNING) {
 123                 prtd->dma_pos += prtd->dma_period;
 124                 if (prtd->dma_pos >= prtd->dma_end)
 125                         prtd->dma_pos = prtd->dma_start;
 126
 127                 if (substream)
 128                         snd_pcm_period_elapsed(substream);
 129
 130                 spin_lock(&prtd->lock);
 131                 if (!samsung_dma_has_circular()) {
 132                         prtd->dma_loaded--;
 133                         dma_enqueue(substream);
 134                 }
 135                 spin_unlock(&prtd->lock);
 136         }
 137 }
 138
 139 static int dma_hw_params(struct snd_pcm_substream *substream,
 140         struct snd_pcm_hw_params *params)
 141 {
 142         struct snd_pcm_runtime *runtime = substream->runtime;
 143         struct runtime_data *prtd = runtime->private_data;
 144         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 145         unsigned long totbytes = params_buffer_bytes(params);
 146         struct s3c_dma_params *dma =
 147                 snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 148         struct samsung_dma_info dma_info;
 149
 150         pr_debug("Entered %s\n", __func__);
 151
 152         /* return if this is a bufferless transfer e.g.
 153          * codec <--> BT codec or GSM modem -- lg FIXME */
 154         if (!dma)
 155                 return 0;
 156
 157         /* this may get called several times by oss emulation
 158          * with different params -HW */
 159         if (prtd->params == NULL) {
 160                 /* prepare DMA */
 161                 prtd->params = dma;
 162
 163                 pr_debug("params %p, client %p, channel %d\n", prtd->params,
 164                         prtd->params->client, prtd->params->channel);
 165
 166                 prtd->params->ops = samsung_dma_get_ops();
 167
 168                 dma_info.cap = (samsung_dma_has_circular() ?
 169                         DMA_CYCLIC : DMA_SLAVE);
 170                 dma_info.client = prtd->params->client;
 171                 dma_info.direction =
 172                         (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 173                         ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
 174                 dma_info.width = prtd->params->dma_size;
 175                 dma_info.fifo = prtd->params->dma_addr;
 176                 prtd->params->ch = prtd->params->ops->request(
 177                                 prtd->params->channel, &dma_info);
 178         }
 179
 180         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 181
 182         runtime->dma_bytes = totbytes;
 183
 184         spin_lock_irq(&prtd->lock);
 185         prtd->dma_loaded = 0;
 186         prtd->dma_period = params_period_bytes(params);
 187         prtd->dma_start = runtime->dma_addr;
 188         prtd->dma_pos = prtd->dma_start;
 189         prtd->dma_end = prtd->dma_start + totbytes;
 190         spin_unlock_irq(&prtd->lock);
 191
 192         return 0;
 193 }
 194
 195 static int dma_hw_free(struct snd_pcm_substream *substream)
 196 {
 197         struct runtime_data *prtd = substream->runtime->private_data;
 198
 199         pr_debug("Entered %s\n", __func__);
 200
 201         /* TODO - do we need to ensure DMA flushed */
 202         snd_pcm_set_runtime_buffer(substream, NULL);
 203
 204         if (prtd->params) {
 205                 prtd->params->ops->release(prtd->params->ch,
 206                                         prtd->params->client);
 207                 prtd->params = NULL;
 208         }
 209
 210         return 0;
 211 }
 212
 213 static int dma_prepare(struct snd_pcm_substream *substream)
 214 {
 215         struct runtime_data *prtd = substream->runtime->private_data;
 216         int ret = 0;
 217
 218         pr_debug("Entered %s\n", __func__);
 219
 220         /* return if this is a bufferless transfer e.g.
 221          * codec <--> BT codec or GSM modem -- lg FIXME */
 222         if (!prtd->params)
 223                 return 0;
 224
 225         /* flush the DMA channel */
 226         prtd->params->ops->flush(prtd->params->ch);
 227
 228         prtd->dma_loaded = 0;
 229         prtd->dma_pos = prtd->dma_start;
 230
 231         /* enqueue dma buffers */
 232         dma_enqueue(substream);
 233
 234         return ret;
 235 }
 236
 237 static int dma_trigger(struct snd_pcm_substream *substream, int cmd)
 238 {
 239         struct runtime_data *prtd = substream->runtime->private_data;
 240         int ret = 0;
 241
 242         pr_debug("Entered %s\n", __func__);
 243
 244         spin_lock(&prtd->lock);
 245
 246         switch (cmd) {
 247         case SNDRV_PCM_TRIGGER_START:
 248         case SNDRV_PCM_TRIGGER_RESUME:
 249         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 250                 prtd->state |= ST_RUNNING;
 251                 prtd->params->ops->trigger(prtd->params->ch);
 252                 break;
 253
 254         case SNDRV_PCM_TRIGGER_STOP:
 255         case SNDRV_PCM_TRIGGER_SUSPEND:
 256         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 257                 prtd->state &= ~ST_RUNNING;
 258                 prtd->params->ops->stop(prtd->params->ch);
 259                 break;
 260
 261         default:
 262                 ret = -EINVAL;
 263                 break;
 264         }
 265
 266         spin_unlock(&prtd->lock);
 267
 268         return ret;
 269 }
 270
 271 static snd_pcm_uframes_t
 272 dma_pointer(struct snd_pcm_substream *substream)
 273 {
 274         struct snd_pcm_runtime *runtime = substream->runtime;
 275         struct runtime_data *prtd = runtime->private_data;
 276         unsigned long res;
 277
 278         pr_debug("Entered %s\n", __func__);
 279
 280         res = prtd->dma_pos - prtd->dma_start;
 281
 282         pr_debug("Pointer offset: %lu\n", res);
 283
 284         /* we seem to be getting the odd error from the pcm library due
 285          * to out-of-bounds pointers. this is maybe due to the dma engine
 286          * not having loaded the new values for the channel before being
 287          * called... (todo - fix )
 288          */
 289
 290         if (res >= snd_pcm_lib_buffer_bytes(substream)) {
 291                 if (res == snd_pcm_lib_buffer_bytes(substream))
 292                         res = 0;
 293         }
 294
 295         return bytes_to_frames(substream->runtime, res);
 296 }
 297
 298 static int dma_open(struct snd_pcm_substream *substream)
 299 {
 300         struct snd_pcm_runtime *runtime = substream->runtime;
 301         struct runtime_data *prtd;
 302
 303         pr_debug("Entered %s\n", __func__);
 304
 305         snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 306         snd_soc_set_runtime_hwparams(substream, &dma_hardware);
 307
 308         prtd = kzalloc(sizeof(struct runtime_data), GFP_KERNEL);
 309         if (prtd == NULL)
 310                 return -ENOMEM;
 311
 312         spin_lock_init(&prtd->lock);
 313
 314         runtime->private_data = prtd;
 315         return 0;
 316 }
 317
 318 static int dma_close(struct snd_pcm_substream *substream)
 319 {
 320         struct snd_pcm_runtime *runtime = substream->runtime;
 321         struct runtime_data *prtd = runtime->private_data;
 322
 323         pr_debug("Entered %s\n", __func__);
 324
 325         if (!prtd)
 326                 pr_debug("dma_close called with prtd == NULL\n");
 327
 328         kfree(prtd);
 329
 330         return 0;
 331 }
 332
 333 static int dma_mmap(struct snd_pcm_substream *substream,
 334         struct vm_area_struct *vma)
 335 {
 336         struct snd_pcm_runtime *runtime = substream->runtime;
 337
 338         pr_debug("Entered %s\n", __func__);
 339
 340         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 341                                      runtime->dma_area,
 342                                      runtime->dma_addr,
 343                                      runtime->dma_bytes);
 344 }
 345
 346 static struct snd_pcm_ops dma_ops = {
 347         .open           = dma_open,
 348         .close          = dma_close,
 349         .ioctl          = snd_pcm_lib_ioctl,
 350         .hw_params      = dma_hw_params,
 351         .hw_free        = dma_hw_free,
 352         .prepare        = dma_prepare,
 353         .trigger        = dma_trigger,
 354         .pointer        = dma_pointer,
 355         .mmap           = dma_mmap,
 356 };
 357
 358 static int preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 359 {
 360         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 361         struct snd_dma_buffer *buf = &substream->dma_buffer;
 362         size_t size = dma_hardware.buffer_bytes_max;
 363
 364         pr_debug("Entered %s\n", __func__);
 365
 366         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 367         buf->dev.dev = pcm->card->dev;
 368         buf->private_data = NULL;
 369         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 370                                            &buf->addr, GFP_KERNEL);
 371         if (!buf->area)
 372                 return -ENOMEM;
 373         buf->bytes = size;
 374         return 0;
 375 }
 376
 377 static void dma_free_dma_buffers(struct snd_pcm *pcm)
 378 {
 379         struct snd_pcm_substream *substream;
 380         struct snd_dma_buffer *buf;
 381         int stream;
 382
 383         pr_debug("Entered %s\n", __func__);
 384
 385         for (stream = 0; stream < 2; stream++) {
 386                 substream = pcm->streams[stream].substream;
 387                 if (!substream)
 388                         continue;
 389
 390                 buf = &substream->dma_buffer;
 391                 if (!buf->area)
 392                         continue;
 393
 394                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 395                                       buf->area, buf->addr);
 396                 buf->area = NULL;
 397         }
 398 }
 399
 400 static u64 dma_mask = DMA_BIT_MASK(32);
 401
 402 static int dma_new(struct snd_soc_pcm_runtime *rtd)
 403 {
 404         struct snd_card *card = rtd->card->snd_card;
 405         struct snd_soc_dai *dai = rtd->cpu_dai;
 406         struct snd_pcm *pcm = rtd->pcm;
 407         int ret = 0;
 408
 409         pr_debug("Entered %s\n", __func__);
 410
 411         if (!card->dev->dma_mask)
 412                 card->dev->dma_mask = &dma_mask;
 413         if (!card->dev->coherent_dma_mask)
 414                 card->dev->coherent_dma_mask = 0xffffffff;
 415
 416         if (dai->driver->playback.channels_min) {
 417                 ret = preallocate_dma_buffer(pcm,
 418                         SNDRV_PCM_STREAM_PLAYBACK);
 419                 if (ret)
 420                         goto out;
 421         }
 422
 423         if (dai->driver->capture.channels_min) {
 424                 ret = preallocate_dma_buffer(pcm,
 425                         SNDRV_PCM_STREAM_CAPTURE);
 426                 if (ret)
 427                         goto out;
 428         }
 429 out:
 430         return ret;
 431 }
 432
 433 static struct snd_soc_platform_driver samsung_asoc_platform = {
 434         .ops            = &dma_ops,
 435         .pcm_new        = dma_new,
 436         .pcm_free       = dma_free_dma_buffers,
 437 };
 438
 439 static int __devinit samsung_asoc_platform_probe(struct platform_device *pdev)
 440 {
 441         return snd_soc_register_platform(&pdev->dev, &samsung_asoc_platform);
 442 }
 443
 444 static int __devexit samsung_asoc_platform_remove(struct platform_device *pdev)
 445 {
 446         snd_soc_unregister_platform(&pdev->dev);
 447         return 0;
 448 }
 449
 450 static struct platform_driver asoc_dma_driver = {
 451         .driver = {
 452                 .name = "samsung-audio",
 453                 .owner = THIS_MODULE,
 454         },
 455
 456         .probe = samsung_asoc_platform_probe,
 457         .remove = __devexit_p(samsung_asoc_platform_remove),
 458 };
 459
 460 static int __init samsung_asoc_init(void)
 461 {
 462         return platform_driver_register(&asoc_dma_driver);
 463 }
 464 module_init(samsung_asoc_init);
 465
 466 static void __exit samsung_asoc_exit(void)
 467 {
 468         platform_driver_unregister(&asoc_dma_driver);
 469 }
 470 module_exit(samsung_asoc_exit);
 471
 472 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
 473 MODULE_DESCRIPTION("Samsung ASoC DMA Driver");
 474 MODULE_LICENSE("GPL");
 475 MODULE_ALIAS("platform:samsung-audio");