sound/soc/s3c24xx/s3c-dma.c

   1 /*
   2  * s3c-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/module.h>
  18 #include <linux/init.h>
  19 #include <linux/io.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/slab.h>
  22 #include <linux/dma-mapping.h>
  23
  24 #include <sound/core.h>
  25 #include <sound/pcm.h>
  26 #include <sound/pcm_params.h>
  27 #include <sound/soc.h>
  28
  29 #include <asm/dma.h>
  30 #include <mach/hardware.h>
  31 #include <mach/dma.h>
  32
  33 #include "s3c-dma.h"
  34
  35 static const struct snd_pcm_hardware s3c_dma_hardware = {
  36         .info                   = SNDRV_PCM_INFO_INTERLEAVED |
  37                                     SNDRV_PCM_INFO_BLOCK_TRANSFER |
  38                                     SNDRV_PCM_INFO_MMAP |
  39                                     SNDRV_PCM_INFO_MMAP_VALID |
  40                                     SNDRV_PCM_INFO_PAUSE |
  41                                     SNDRV_PCM_INFO_RESUME,
  42         .formats                = SNDRV_PCM_FMTBIT_S16_LE |
  43                                     SNDRV_PCM_FMTBIT_U16_LE |
  44                                     SNDRV_PCM_FMTBIT_U8 |
  45                                     SNDRV_PCM_FMTBIT_S8,
  46         .channels_min           = 2,
  47         .channels_max           = 2,
  48         .buffer_bytes_max       = 128*1024,
  49         .period_bytes_min       = PAGE_SIZE,
  50         .period_bytes_max       = PAGE_SIZE*2,
  51         .periods_min            = 2,
  52         .periods_max            = 128,
  53         .fifo_size              = 32,
  54 };
  55
  56 struct s3c24xx_runtime_data {
  57         spinlock_t lock;
  58         int state;
  59         unsigned int dma_loaded;
  60         unsigned int dma_limit;
  61         unsigned int dma_period;
  62         dma_addr_t dma_start;
  63         dma_addr_t dma_pos;
  64         dma_addr_t dma_end;
  65         struct s3c_dma_params *params;
  66 };
  67
  68 /* s3c_dma_enqueue
  69  *
  70  * place a dma buffer onto the queue for the dma system
  71  * to handle.
  72 */
  73 static void s3c_dma_enqueue(struct snd_pcm_substream *substream)
  74 {
  75         struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
  76         dma_addr_t pos = prtd->dma_pos;
  77         unsigned int limit;
  78         int ret;
  79
  80         pr_debug("Entered %s\n", __func__);
  81
  82         if (s3c_dma_has_circular())
  83                 limit = (prtd->dma_end - prtd->dma_start) / prtd->dma_period;
  84         else
  85                 limit = prtd->dma_limit;
  86
  87         pr_debug("%s: loaded %d, limit %d\n",
  88                                 __func__, prtd->dma_loaded, limit);
  89
  90         while (prtd->dma_loaded < limit) {
  91                 unsigned long len = prtd->dma_period;
  92
  93                 pr_debug("dma_loaded: %d\n", prtd->dma_loaded);
  94
  95                 if ((pos + len) > prtd->dma_end) {
  96                         len  = prtd->dma_end - pos;
  97                         pr_debug(KERN_DEBUG "%s: corrected dma len %ld\n",
  98                                __func__, len);
  99                 }
 100
 101                 ret = s3c2410_dma_enqueue(prtd->params->channel,
 102                         substream, pos, len);
 103
 104                 if (ret == 0) {
 105                         prtd->dma_loaded++;
 106                         pos += prtd->dma_period;
 107                         if (pos >= prtd->dma_end)
 108                                 pos = prtd->dma_start;
 109                 } else
 110                         break;
 111         }
 112
 113         prtd->dma_pos = pos;
 114 }
 115
 116 static void s3c24xx_audio_buffdone(struct s3c2410_dma_chan *channel,
 117                                 void *dev_id, int size,
 118                                 enum s3c2410_dma_buffresult result)
 119 {
 120         struct snd_pcm_substream *substream = dev_id;
 121         struct s3c24xx_runtime_data *prtd;
 122
 123         pr_debug("Entered %s\n", __func__);
 124
 125         if (result == S3C2410_RES_ABORT || result == S3C2410_RES_ERR)
 126                 return;
 127
 128         prtd = substream->runtime->private_data;
 129
 130         if (substream)
 131                 snd_pcm_period_elapsed(substream);
 132
 133         spin_lock(&prtd->lock);
 134         if (prtd->state & ST_RUNNING && !s3c_dma_has_circular()) {
 135                 prtd->dma_loaded--;
 136                 s3c_dma_enqueue(substream);
 137         }
 138
 139         spin_unlock(&prtd->lock);
 140 }
 141
 142 static int s3c_dma_hw_params(struct snd_pcm_substream *substream,
 143         struct snd_pcm_hw_params *params)
 144 {
 145         struct snd_pcm_runtime *runtime = substream->runtime;
 146         struct s3c24xx_runtime_data *prtd = runtime->private_data;
 147         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 148         unsigned long totbytes = params_buffer_bytes(params);
 149         struct s3c_dma_params *dma =
 150                 snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 151         int ret = 0;
 152
 153
 154         pr_debug("Entered %s\n", __func__);
 155
 156         /* return if this is a bufferless transfer e.g.
 157          * codec <--> BT codec or GSM modem -- lg FIXME */
 158         if (!dma)
 159                 return 0;
 160
 161         /* this may get called several times by oss emulation
 162          * with different params -HW */
 163         if (prtd->params == NULL) {
 164                 /* prepare DMA */
 165                 prtd->params = dma;
 166
 167                 pr_debug("params %p, client %p, channel %d\n", prtd->params,
 168                         prtd->params->client, prtd->params->channel);
 169
 170                 ret = s3c2410_dma_request(prtd->params->channel,
 171                                           prtd->params->client, NULL);
 172
 173                 if (ret < 0) {
 174                         printk(KERN_ERR "failed to get dma channel\n");
 175                         return ret;
 176                 }
 177
 178                 /* use the circular buffering if we have it available. */
 179                 if (s3c_dma_has_circular())
 180                         s3c2410_dma_setflags(prtd->params->channel,
 181                                              S3C2410_DMAF_CIRCULAR);
 182         }
 183
 184         s3c2410_dma_set_buffdone_fn(prtd->params->channel,
 185                                     s3c24xx_audio_buffdone);
 186
 187         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 188
 189         runtime->dma_bytes = totbytes;
 190
 191         spin_lock_irq(&prtd->lock);
 192         prtd->dma_loaded = 0;
 193         prtd->dma_limit = runtime->hw.periods_min;
 194         prtd->dma_period = params_period_bytes(params);
 195         prtd->dma_start = runtime->dma_addr;
 196         prtd->dma_pos = prtd->dma_start;
 197         prtd->dma_end = prtd->dma_start + totbytes;
 198         spin_unlock_irq(&prtd->lock);
 199
 200         return 0;
 201 }
 202
 203 static int s3c_dma_hw_free(struct snd_pcm_substream *substream)
 204 {
 205         struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
 206
 207         pr_debug("Entered %s\n", __func__);
 208
 209         /* TODO - do we need to ensure DMA flushed */
 210         snd_pcm_set_runtime_buffer(substream, NULL);
 211
 212         if (prtd->params) {
 213                 s3c2410_dma_free(prtd->params->channel, prtd->params->client);
 214                 prtd->params = NULL;
 215         }
 216
 217         return 0;
 218 }
 219
 220 static int s3c_dma_prepare(struct snd_pcm_substream *substream)
 221 {
 222         struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
 223         int ret = 0;
 224
 225         pr_debug("Entered %s\n", __func__);
 226
 227         /* return if this is a bufferless transfer e.g.
 228          * codec <--> BT codec or GSM modem -- lg FIXME */
 229         if (!prtd->params)
 230                 return 0;
 231
 232         /* channel needs configuring for mem=>device, increment memory addr,
 233          * sync to pclk, half-word transfers to the IIS-FIFO. */
 234         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 235                 s3c2410_dma_devconfig(prtd->params->channel,
 236                                       S3C2410_DMASRC_MEM,
 237                                       prtd->params->dma_addr);
 238         } else {
 239                 s3c2410_dma_devconfig(prtd->params->channel,
 240                                       S3C2410_DMASRC_HW,
 241                                       prtd->params->dma_addr);
 242         }
 243
 244         s3c2410_dma_config(prtd->params->channel,
 245                            prtd->params->dma_size);
 246
 247         /* flush the DMA channel */
 248         s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_FLUSH);
 249         prtd->dma_loaded = 0;
 250         prtd->dma_pos = prtd->dma_start;
 251
 252         /* enqueue dma buffers */
 253         s3c_dma_enqueue(substream);
 254
 255         return ret;
 256 }
 257
 258 static int s3c_dma_trigger(struct snd_pcm_substream *substream, int cmd)
 259 {
 260         struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
 261         int ret = 0;
 262
 263         pr_debug("Entered %s\n", __func__);
 264
 265         spin_lock(&prtd->lock);
 266
 267         switch (cmd) {
 268         case SNDRV_PCM_TRIGGER_START:
 269         case SNDRV_PCM_TRIGGER_RESUME:
 270         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 271                 prtd->state |= ST_RUNNING;
 272                 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_START);
 273                 break;
 274
 275         case SNDRV_PCM_TRIGGER_STOP:
 276         case SNDRV_PCM_TRIGGER_SUSPEND:
 277         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 278                 prtd->state &= ~ST_RUNNING;
 279                 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_STOP);
 280                 break;
 281
 282         default:
 283                 ret = -EINVAL;
 284                 break;
 285         }
 286
 287         spin_unlock(&prtd->lock);
 288
 289         return ret;
 290 }
 291
 292 static snd_pcm_uframes_t
 293 s3c_dma_pointer(struct snd_pcm_substream *substream)
 294 {
 295         struct snd_pcm_runtime *runtime = substream->runtime;
 296         struct s3c24xx_runtime_data *prtd = runtime->private_data;
 297         unsigned long res;
 298         dma_addr_t src, dst;
 299
 300         pr_debug("Entered %s\n", __func__);
 301
 302         spin_lock(&prtd->lock);
 303         s3c2410_dma_getposition(prtd->params->channel, &src, &dst);
 304
 305         if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
 306                 res = dst - prtd->dma_start;
 307         else
 308                 res = src - prtd->dma_start;
 309
 310         spin_unlock(&prtd->lock);
 311
 312         pr_debug("Pointer %x %x\n", src, dst);
 313
 314         /* we seem to be getting the odd error from the pcm library due
 315          * to out-of-bounds pointers. this is maybe due to the dma engine
 316          * not having loaded the new values for the channel before being
 317          * callled... (todo - fix )
 318          */
 319
 320         if (res >= snd_pcm_lib_buffer_bytes(substream)) {
 321                 if (res == snd_pcm_lib_buffer_bytes(substream))
 322                         res = 0;
 323         }
 324
 325         return bytes_to_frames(substream->runtime, res);
 326 }
 327
 328 static int s3c_dma_open(struct snd_pcm_substream *substream)
 329 {
 330         struct snd_pcm_runtime *runtime = substream->runtime;
 331         struct s3c24xx_runtime_data *prtd;
 332
 333         pr_debug("Entered %s\n", __func__);
 334
 335         snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 336         snd_soc_set_runtime_hwparams(substream, &s3c_dma_hardware);
 337
 338         prtd = kzalloc(sizeof(struct s3c24xx_runtime_data), GFP_KERNEL);
 339         if (prtd == NULL)
 340                 return -ENOMEM;
 341
 342         spin_lock_init(&prtd->lock);
 343
 344         runtime->private_data = prtd;
 345         return 0;
 346 }
 347
 348 static int s3c_dma_close(struct snd_pcm_substream *substream)
 349 {
 350         struct snd_pcm_runtime *runtime = substream->runtime;
 351         struct s3c24xx_runtime_data *prtd = runtime->private_data;
 352
 353         pr_debug("Entered %s\n", __func__);
 354
 355         if (!prtd)
 356                 pr_debug("s3c_dma_close called with prtd == NULL\n");
 357
 358         kfree(prtd);
 359
 360         return 0;
 361 }
 362
 363 static int s3c_dma_mmap(struct snd_pcm_substream *substream,
 364         struct vm_area_struct *vma)
 365 {
 366         struct snd_pcm_runtime *runtime = substream->runtime;
 367
 368         pr_debug("Entered %s\n", __func__);
 369
 370         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 371                                      runtime->dma_area,
 372                                      runtime->dma_addr,
 373                                      runtime->dma_bytes);
 374 }
 375
 376 static struct snd_pcm_ops s3c_dma_ops = {
 377         .open           = s3c_dma_open,
 378         .close          = s3c_dma_close,
 379         .ioctl          = snd_pcm_lib_ioctl,
 380         .hw_params      = s3c_dma_hw_params,
 381         .hw_free        = s3c_dma_hw_free,
 382         .prepare        = s3c_dma_prepare,
 383         .trigger        = s3c_dma_trigger,
 384         .pointer        = s3c_dma_pointer,
 385         .mmap           = s3c_dma_mmap,
 386 };
 387
 388 static int s3c_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 389 {
 390         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 391         struct snd_dma_buffer *buf = &substream->dma_buffer;
 392         size_t size = s3c_dma_hardware.buffer_bytes_max;
 393
 394         pr_debug("Entered %s\n", __func__);
 395
 396         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 397         buf->dev.dev = pcm->card->dev;
 398         buf->private_data = NULL;
 399         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 400                                            &buf->addr, GFP_KERNEL);
 401         if (!buf->area)
 402                 return -ENOMEM;
 403         buf->bytes = size;
 404         return 0;
 405 }
 406
 407 static void s3c_dma_free_dma_buffers(struct snd_pcm *pcm)
 408 {
 409         struct snd_pcm_substream *substream;
 410         struct snd_dma_buffer *buf;
 411         int stream;
 412
 413         pr_debug("Entered %s\n", __func__);
 414
 415         for (stream = 0; stream < 2; stream++) {
 416                 substream = pcm->streams[stream].substream;
 417                 if (!substream)
 418                         continue;
 419
 420                 buf = &substream->dma_buffer;
 421                 if (!buf->area)
 422                         continue;
 423
 424                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 425                                       buf->area, buf->addr);
 426                 buf->area = NULL;
 427         }
 428 }
 429
 430 static u64 s3c_dma_mask = DMA_BIT_MASK(32);
 431
 432 static int s3c_dma_new(struct snd_card *card,
 433         struct snd_soc_dai *dai, struct snd_pcm *pcm)
 434 {
 435         int ret = 0;
 436
 437         pr_debug("Entered %s\n", __func__);
 438
 439         if (!card->dev->dma_mask)
 440                 card->dev->dma_mask = &s3c_dma_mask;
 441         if (!card->dev->coherent_dma_mask)
 442                 card->dev->coherent_dma_mask = 0xffffffff;
 443
 444         if (dai->driver->playback.channels_min) {
 445                 ret = s3c_preallocate_dma_buffer(pcm,
 446                         SNDRV_PCM_STREAM_PLAYBACK);
 447                 if (ret)
 448                         goto out;
 449         }
 450
 451         if (dai->driver->capture.channels_min) {
 452                 ret = s3c_preallocate_dma_buffer(pcm,
 453                         SNDRV_PCM_STREAM_CAPTURE);
 454                 if (ret)
 455                         goto out;
 456         }
 457  out:
 458         return ret;
 459 }
 460
 461 static struct snd_soc_platform_driver s3c24xx_soc_platform = {
 462         .ops            = &s3c_dma_ops,
 463         .pcm_new        = s3c_dma_new,
 464         .pcm_free       = s3c_dma_free_dma_buffers,
 465 };
 466
 467 static int __devinit s3c24xx_soc_platform_probe(struct platform_device *pdev)
 468 {
 469         return snd_soc_register_platform(&pdev->dev, &s3c24xx_soc_platform);
 470 }
 471
 472 static int __devexit s3c24xx_soc_platform_remove(struct platform_device *pdev)
 473 {
 474         snd_soc_unregister_platform(&pdev->dev);
 475         return 0;
 476 }
 477
 478 static struct platform_driver s3c24xx_pcm_driver = {
 479         .driver = {
 480                 .name = "s3c24xx-pcm-audio",
 481                 .owner = THIS_MODULE,
 482         },
 483
 484         .probe = s3c24xx_soc_platform_probe,
 485         .remove = __devexit_p(s3c24xx_soc_platform_remove),
 486 };
 487
 488 static int __init snd_s3c24xx_pcm_init(void)
 489 {
 490         return platform_driver_register(&s3c24xx_pcm_driver);
 491 }
 492 module_init(snd_s3c24xx_pcm_init);
 493
 494 static void __exit snd_s3c24xx_pcm_exit(void)
 495 {
 496         platform_driver_unregister(&s3c24xx_pcm_driver);
 497 }
 498 module_exit(snd_s3c24xx_pcm_exit);
 499
 500 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
 501 MODULE_DESCRIPTION("Samsung S3C Audio DMA module");
 502 MODULE_LICENSE("GPL");