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         struct s3c_dma_params *dma = rtd->dai->cpu_dai->dma_data;
 149         unsigned long totbytes = params_buffer_bytes(params);
 150         int ret = 0;
 151
 152         pr_debug("Entered %s\n", __func__);
 153
 154         /* return if this is a bufferless transfer e.g.
 155          * codec <--> BT codec or GSM modem -- lg FIXME */
 156         if (!dma)
 157                 return 0;
 158
 159         /* this may get called several times by oss emulation
 160          * with different params -HW */
 161         if (prtd->params == NULL) {
 162                 /* prepare DMA */
 163                 prtd->params = dma;
 164
 165                 pr_debug("params %p, client %p, channel %d\n", prtd->params,
 166                         prtd->params->client, prtd->params->channel);
 167
 168                 ret = s3c2410_dma_request(prtd->params->channel,
 169                                           prtd->params->client, NULL);
 170
 171                 if (ret < 0) {
 172                         printk(KERN_ERR "failed to get dma channel\n");
 173                         return ret;
 174                 }
 175
 176                 /* use the circular buffering if we have it available. */
 177                 if (s3c_dma_has_circular())
 178                         s3c2410_dma_setflags(prtd->params->channel,
 179                                              S3C2410_DMAF_CIRCULAR);
 180         }
 181
 182         s3c2410_dma_set_buffdone_fn(prtd->params->channel,
 183                                     s3c24xx_audio_buffdone);
 184
 185         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 186
 187         runtime->dma_bytes = totbytes;
 188
 189         spin_lock_irq(&prtd->lock);
 190         prtd->dma_loaded = 0;
 191         prtd->dma_limit = runtime->hw.periods_min;
 192         prtd->dma_period = params_period_bytes(params);
 193         prtd->dma_start = runtime->dma_addr;
 194         prtd->dma_pos = prtd->dma_start;
 195         prtd->dma_end = prtd->dma_start + totbytes;
 196         spin_unlock_irq(&prtd->lock);
 197
 198         return 0;
 199 }
 200
 201 static int s3c_dma_hw_free(struct snd_pcm_substream *substream)
 202 {
 203         struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
 204
 205         pr_debug("Entered %s\n", __func__);
 206
 207         /* TODO - do we need to ensure DMA flushed */
 208         snd_pcm_set_runtime_buffer(substream, NULL);
 209
 210         if (prtd->params) {
 211                 s3c2410_dma_free(prtd->params->channel, prtd->params->client);
 212                 prtd->params = NULL;
 213         }
 214
 215         return 0;
 216 }
 217
 218 static int s3c_dma_prepare(struct snd_pcm_substream *substream)
 219 {
 220         struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
 221         int ret = 0;
 222
 223         pr_debug("Entered %s\n", __func__);
 224
 225         /* return if this is a bufferless transfer e.g.
 226          * codec <--> BT codec or GSM modem -- lg FIXME */
 227         if (!prtd->params)
 228                 return 0;
 229
 230         /* channel needs configuring for mem=>device, increment memory addr,
 231          * sync to pclk, half-word transfers to the IIS-FIFO. */
 232         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 233                 s3c2410_dma_devconfig(prtd->params->channel,
 234                                       S3C2410_DMASRC_MEM,
 235                                       prtd->params->dma_addr);
 236         } else {
 237                 s3c2410_dma_devconfig(prtd->params->channel,
 238                                       S3C2410_DMASRC_HW,
 239                                       prtd->params->dma_addr);
 240         }
 241
 242         s3c2410_dma_config(prtd->params->channel,
 243                            prtd->params->dma_size);
 244
 245         /* flush the DMA channel */
 246         s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_FLUSH);
 247         prtd->dma_loaded = 0;
 248         prtd->dma_pos = prtd->dma_start;
 249
 250         /* enqueue dma buffers */
 251         s3c_dma_enqueue(substream);
 252
 253         return ret;
 254 }
 255
 256 static int s3c_dma_trigger(struct snd_pcm_substream *substream, int cmd)
 257 {
 258         struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
 259         int ret = 0;
 260
 261         pr_debug("Entered %s\n", __func__);
 262
 263         spin_lock(&prtd->lock);
 264
 265         switch (cmd) {
 266         case SNDRV_PCM_TRIGGER_START:
 267         case SNDRV_PCM_TRIGGER_RESUME:
 268         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 269                 prtd->state |= ST_RUNNING;
 270                 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_START);
 271                 break;
 272
 273         case SNDRV_PCM_TRIGGER_STOP:
 274         case SNDRV_PCM_TRIGGER_SUSPEND:
 275         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 276                 prtd->state &= ~ST_RUNNING;
 277                 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_STOP);
 278                 break;
 279
 280         default:
 281                 ret = -EINVAL;
 282                 break;
 283         }
 284
 285         spin_unlock(&prtd->lock);
 286
 287         return ret;
 288 }
 289
 290 static snd_pcm_uframes_t
 291 s3c_dma_pointer(struct snd_pcm_substream *substream)
 292 {
 293         struct snd_pcm_runtime *runtime = substream->runtime;
 294         struct s3c24xx_runtime_data *prtd = runtime->private_data;
 295         unsigned long res;
 296         dma_addr_t src, dst;
 297
 298         pr_debug("Entered %s\n", __func__);
 299
 300         spin_lock(&prtd->lock);
 301         s3c2410_dma_getposition(prtd->params->channel, &src, &dst);
 302
 303         if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
 304                 res = dst - prtd->dma_start;
 305         else
 306                 res = src - prtd->dma_start;
 307
 308         spin_unlock(&prtd->lock);
 309
 310         pr_debug("Pointer %x %x\n", src, dst);
 311
 312         /* we seem to be getting the odd error from the pcm library due
 313          * to out-of-bounds pointers. this is maybe due to the dma engine
 314          * not having loaded the new values for the channel before being
 315          * callled... (todo - fix )
 316          */
 317
 318         if (res >= snd_pcm_lib_buffer_bytes(substream)) {
 319                 if (res == snd_pcm_lib_buffer_bytes(substream))
 320                         res = 0;
 321         }
 322
 323         return bytes_to_frames(substream->runtime, res);
 324 }
 325
 326 static int s3c_dma_open(struct snd_pcm_substream *substream)
 327 {
 328         struct snd_pcm_runtime *runtime = substream->runtime;
 329         struct s3c24xx_runtime_data *prtd;
 330
 331         pr_debug("Entered %s\n", __func__);
 332
 333         snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 334         snd_soc_set_runtime_hwparams(substream, &s3c_dma_hardware);
 335
 336         prtd = kzalloc(sizeof(struct s3c24xx_runtime_data), GFP_KERNEL);
 337         if (prtd == NULL)
 338                 return -ENOMEM;
 339
 340         spin_lock_init(&prtd->lock);
 341
 342         runtime->private_data = prtd;
 343         return 0;
 344 }
 345
 346 static int s3c_dma_close(struct snd_pcm_substream *substream)
 347 {
 348         struct snd_pcm_runtime *runtime = substream->runtime;
 349         struct s3c24xx_runtime_data *prtd = runtime->private_data;
 350
 351         pr_debug("Entered %s\n", __func__);
 352
 353         if (!prtd)
 354                 pr_debug("s3c_dma_close called with prtd == NULL\n");
 355
 356         kfree(prtd);
 357
 358         return 0;
 359 }
 360
 361 static int s3c_dma_mmap(struct snd_pcm_substream *substream,
 362         struct vm_area_struct *vma)
 363 {
 364         struct snd_pcm_runtime *runtime = substream->runtime;
 365
 366         pr_debug("Entered %s\n", __func__);
 367
 368         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 369                                      runtime->dma_area,
 370                                      runtime->dma_addr,
 371                                      runtime->dma_bytes);
 372 }
 373
 374 static struct snd_pcm_ops s3c_dma_ops = {
 375         .open           = s3c_dma_open,
 376         .close          = s3c_dma_close,
 377         .ioctl          = snd_pcm_lib_ioctl,
 378         .hw_params      = s3c_dma_hw_params,
 379         .hw_free        = s3c_dma_hw_free,
 380         .prepare        = s3c_dma_prepare,
 381         .trigger        = s3c_dma_trigger,
 382         .pointer        = s3c_dma_pointer,
 383         .mmap           = s3c_dma_mmap,
 384 };
 385
 386 static int s3c_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 387 {
 388         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 389         struct snd_dma_buffer *buf = &substream->dma_buffer;
 390         size_t size = s3c_dma_hardware.buffer_bytes_max;
 391
 392         pr_debug("Entered %s\n", __func__);
 393
 394         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 395         buf->dev.dev = pcm->card->dev;
 396         buf->private_data = NULL;
 397         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 398                                            &buf->addr, GFP_KERNEL);
 399         if (!buf->area)
 400                 return -ENOMEM;
 401         buf->bytes = size;
 402         return 0;
 403 }
 404
 405 static void s3c_dma_free_dma_buffers(struct snd_pcm *pcm)
 406 {
 407         struct snd_pcm_substream *substream;
 408         struct snd_dma_buffer *buf;
 409         int stream;
 410
 411         pr_debug("Entered %s\n", __func__);
 412
 413         for (stream = 0; stream < 2; stream++) {
 414                 substream = pcm->streams[stream].substream;
 415                 if (!substream)
 416                         continue;
 417
 418                 buf = &substream->dma_buffer;
 419                 if (!buf->area)
 420                         continue;
 421
 422                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 423                                       buf->area, buf->addr);
 424                 buf->area = NULL;
 425         }
 426 }
 427
 428 static u64 s3c_dma_mask = DMA_BIT_MASK(32);
 429
 430 static int s3c_dma_new(struct snd_card *card,
 431         struct snd_soc_dai *dai, struct snd_pcm *pcm)
 432 {
 433         int ret = 0;
 434
 435         pr_debug("Entered %s\n", __func__);
 436
 437         if (!card->dev->dma_mask)
 438                 card->dev->dma_mask = &s3c_dma_mask;
 439         if (!card->dev->coherent_dma_mask)
 440                 card->dev->coherent_dma_mask = 0xffffffff;
 441
 442         if (dai->playback.channels_min) {
 443                 ret = s3c_preallocate_dma_buffer(pcm,
 444                         SNDRV_PCM_STREAM_PLAYBACK);
 445                 if (ret)
 446                         goto out;
 447         }
 448
 449         if (dai->capture.channels_min) {
 450                 ret = s3c_preallocate_dma_buffer(pcm,
 451                         SNDRV_PCM_STREAM_CAPTURE);
 452                 if (ret)
 453                         goto out;
 454         }
 455  out:
 456         return ret;
 457 }
 458
 459 struct snd_soc_platform s3c24xx_soc_platform = {
 460         .name           = "s3c24xx-audio",
 461         .pcm_ops        = &s3c_dma_ops,
 462         .pcm_new        = s3c_dma_new,
 463         .pcm_free       = s3c_dma_free_dma_buffers,
 464 };
 465 EXPORT_SYMBOL_GPL(s3c24xx_soc_platform);
 466
 467 static int __init s3c24xx_soc_platform_init(void)
 468 {
 469         return snd_soc_register_platform(&s3c24xx_soc_platform);
 470 }
 471 module_init(s3c24xx_soc_platform_init);
 472
 473 static void __exit s3c24xx_soc_platform_exit(void)
 474 {
 475         snd_soc_unregister_platform(&s3c24xx_soc_platform);
 476 }
 477 module_exit(s3c24xx_soc_platform_exit);
 478
 479 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
 480 MODULE_DESCRIPTION("Samsung S3C Audio DMA module");
 481 MODULE_LICENSE("GPL");