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