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("%s: corrected dma len %ld\n", __func__, len);
  98                 }
  99
 100                 ret = s3c2410_dma_enqueue(prtd->params->channel,
 101                         substream, pos, len);
 102
 103                 if (ret == 0) {
 104                         prtd->dma_loaded++;
 105                         pos += prtd->dma_period;
 106                         if (pos >= prtd->dma_end)
 107                                 pos = prtd->dma_start;
 108                 } else
 109                         break;
 110         }
 111
 112         prtd->dma_pos = pos;
 113 }
 114
 115 static void s3c24xx_audio_buffdone(struct s3c2410_dma_chan *channel,
 116                                 void *dev_id, int size,
 117                                 enum s3c2410_dma_buffresult result)
 118 {
 119         struct snd_pcm_substream *substream = dev_id;
 120         struct s3c24xx_runtime_data *prtd;
 121
 122         pr_debug("Entered %s\n", __func__);
 123
 124         if (result == S3C2410_RES_ABORT || result == S3C2410_RES_ERR)
 125                 return;
 126
 127         prtd = substream->runtime->private_data;
 128
 129         if (substream)
 130                 snd_pcm_period_elapsed(substream);
 131
 132         spin_lock(&prtd->lock);
 133         if (prtd->state & ST_RUNNING && !s3c_dma_has_circular()) {
 134                 prtd->dma_loaded--;
 135                 s3c_dma_enqueue(substream);
 136         }
 137
 138         spin_unlock(&prtd->lock);
 139 }
 140
 141 static int s3c_dma_hw_params(struct snd_pcm_substream *substream,
 142         struct snd_pcm_hw_params *params)
 143 {
 144         struct snd_pcm_runtime *runtime = substream->runtime;
 145         struct s3c24xx_runtime_data *prtd = runtime->private_data;
 146         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 147         unsigned long totbytes = params_buffer_bytes(params);
 148         struct s3c_dma_params *dma =
 149                 snd_soc_dai_get_dma_data(rtd->dai->cpu_dai, substream);
 150         int ret = 0;
 151
 152
 153         pr_debug("Entered %s\n", __func__);
 154
 155         /* return if this is a bufferless transfer e.g.
 156          * codec <--> BT codec or GSM modem -- lg FIXME */
 157         if (!dma)
 158                 return 0;
 159
 160         /* this may get called several times by oss emulation
 161          * with different params -HW */
 162         if (prtd->params == NULL) {
 163                 /* prepare DMA */
 164                 prtd->params = dma;
 165
 166                 pr_debug("params %p, client %p, channel %d\n", prtd->params,
 167                         prtd->params->client, prtd->params->channel);
 168
 169                 ret = s3c2410_dma_request(prtd->params->channel,
 170                                           prtd->params->client, NULL);
 171
 172                 if (ret < 0) {
 173                         printk(KERN_ERR "failed to get dma channel\n");
 174                         return ret;
 175                 }
 176
 177                 /* use the circular buffering if we have it available. */
 178                 if (s3c_dma_has_circular())
 179                         s3c2410_dma_setflags(prtd->params->channel,
 180                                              S3C2410_DMAF_CIRCULAR);
 181         }
 182
 183         s3c2410_dma_set_buffdone_fn(prtd->params->channel,
 184                                     s3c24xx_audio_buffdone);
 185
 186         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 187
 188         runtime->dma_bytes = totbytes;
 189
 190         spin_lock_irq(&prtd->lock);
 191         prtd->dma_loaded = 0;
 192         prtd->dma_limit = runtime->hw.periods_min;
 193         prtd->dma_period = params_period_bytes(params);
 194         prtd->dma_start = runtime->dma_addr;
 195         prtd->dma_pos = prtd->dma_start;
 196         prtd->dma_end = prtd->dma_start + totbytes;
 197         spin_unlock_irq(&prtd->lock);
 198
 199         return 0;
 200 }
 201
 202 static int s3c_dma_hw_free(struct snd_pcm_substream *substream)
 203 {
 204         struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
 205
 206         pr_debug("Entered %s\n", __func__);
 207
 208         /* TODO - do we need to ensure DMA flushed */
 209         snd_pcm_set_runtime_buffer(substream, NULL);
 210
 211         if (prtd->params) {
 212                 s3c2410_dma_free(prtd->params->channel, prtd->params->client);
 213                 prtd->params = NULL;
 214         }
 215
 216         return 0;
 217 }
 218
 219 static int s3c_dma_prepare(struct snd_pcm_substream *substream)
 220 {
 221         struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
 222         int ret = 0;
 223
 224         pr_debug("Entered %s\n", __func__);
 225
 226         /* return if this is a bufferless transfer e.g.
 227          * codec <--> BT codec or GSM modem -- lg FIXME */
 228         if (!prtd->params)
 229                 return 0;
 230
 231         /* channel needs configuring for mem=>device, increment memory addr,
 232          * sync to pclk, half-word transfers to the IIS-FIFO. */
 233         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 234                 s3c2410_dma_devconfig(prtd->params->channel,
 235                                       S3C2410_DMASRC_MEM,
 236                                       prtd->params->dma_addr);
 237         } else {
 238                 s3c2410_dma_devconfig(prtd->params->channel,
 239                                       S3C2410_DMASRC_HW,
 240                                       prtd->params->dma_addr);
 241         }
 242
 243         s3c2410_dma_config(prtd->params->channel,
 244                            prtd->params->dma_size);
 245
 246         /* flush the DMA channel */
 247         s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_FLUSH);
 248         prtd->dma_loaded = 0;
 249         prtd->dma_pos = prtd->dma_start;
 250
 251         /* enqueue dma buffers */
 252         s3c_dma_enqueue(substream);
 253
 254         return ret;
 255 }
 256
 257 static int s3c_dma_trigger(struct snd_pcm_substream *substream, int cmd)
 258 {
 259         struct s3c24xx_runtime_data *prtd = substream->runtime->private_data;
 260         int ret = 0;
 261
 262         pr_debug("Entered %s\n", __func__);
 263
 264         spin_lock(&prtd->lock);
 265
 266         switch (cmd) {
 267         case SNDRV_PCM_TRIGGER_START:
 268         case SNDRV_PCM_TRIGGER_RESUME:
 269         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 270                 prtd->state |= ST_RUNNING;
 271                 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_START);
 272                 break;
 273
 274         case SNDRV_PCM_TRIGGER_STOP:
 275         case SNDRV_PCM_TRIGGER_SUSPEND:
 276         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 277                 prtd->state &= ~ST_RUNNING;
 278                 s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_STOP);
 279                 break;
 280
 281         default:
 282                 ret = -EINVAL;
 283                 break;
 284         }
 285
 286         spin_unlock(&prtd->lock);
 287
 288         return ret;
 289 }
 290
 291 static snd_pcm_uframes_t
 292 s3c_dma_pointer(struct snd_pcm_substream *substream)
 293 {
 294         struct snd_pcm_runtime *runtime = substream->runtime;
 295         struct s3c24xx_runtime_data *prtd = runtime->private_data;
 296         unsigned long res;
 297         dma_addr_t src, dst;
 298
 299         pr_debug("Entered %s\n", __func__);
 300
 301         spin_lock(&prtd->lock);
 302         s3c2410_dma_getposition(prtd->params->channel, &src, &dst);
 303
 304         if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
 305                 res = dst - prtd->dma_start;
 306         else
 307                 res = src - prtd->dma_start;
 308
 309         spin_unlock(&prtd->lock);
 310
 311         pr_debug("Pointer %x %x\n", src, dst);
 312
 313         /* we seem to be getting the odd error from the pcm library due
 314          * to out-of-bounds pointers. this is maybe due to the dma engine
 315          * not having loaded the new values for the channel before being
 316          * callled... (todo - fix )
 317          */
 318
 319         if (res >= snd_pcm_lib_buffer_bytes(substream)) {
 320                 if (res == snd_pcm_lib_buffer_bytes(substream))
 321                         res = 0;
 322         }
 323
 324         return bytes_to_frames(substream->runtime, res);
 325 }
 326
 327 static int s3c_dma_open(struct snd_pcm_substream *substream)
 328 {
 329         struct snd_pcm_runtime *runtime = substream->runtime;
 330         struct s3c24xx_runtime_data *prtd;
 331
 332         pr_debug("Entered %s\n", __func__);
 333
 334         snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 335         snd_soc_set_runtime_hwparams(substream, &s3c_dma_hardware);
 336
 337         prtd = kzalloc(sizeof(struct s3c24xx_runtime_data), GFP_KERNEL);
 338         if (prtd == NULL)
 339                 return -ENOMEM;
 340
 341         spin_lock_init(&prtd->lock);
 342
 343         runtime->private_data = prtd;
 344         return 0;
 345 }
 346
 347 static int s3c_dma_close(struct snd_pcm_substream *substream)
 348 {
 349         struct snd_pcm_runtime *runtime = substream->runtime;
 350         struct s3c24xx_runtime_data *prtd = runtime->private_data;
 351
 352         pr_debug("Entered %s\n", __func__);
 353
 354         if (!prtd)
 355                 pr_debug("s3c_dma_close called with prtd == NULL\n");
 356
 357         kfree(prtd);
 358
 359         return 0;
 360 }
 361
 362 static int s3c_dma_mmap(struct snd_pcm_substream *substream,
 363         struct vm_area_struct *vma)
 364 {
 365         struct snd_pcm_runtime *runtime = substream->runtime;
 366
 367         pr_debug("Entered %s\n", __func__);
 368
 369         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 370                                      runtime->dma_area,
 371                                      runtime->dma_addr,
 372                                      runtime->dma_bytes);
 373 }
 374
 375 static struct snd_pcm_ops s3c_dma_ops = {
 376         .open           = s3c_dma_open,
 377         .close          = s3c_dma_close,
 378         .ioctl          = snd_pcm_lib_ioctl,
 379         .hw_params      = s3c_dma_hw_params,
 380         .hw_free        = s3c_dma_hw_free,
 381         .prepare        = s3c_dma_prepare,
 382         .trigger        = s3c_dma_trigger,
 383         .pointer        = s3c_dma_pointer,
 384         .mmap           = s3c_dma_mmap,
 385 };
 386
 387 static int s3c_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 388 {
 389         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 390         struct snd_dma_buffer *buf = &substream->dma_buffer;
 391         size_t size = s3c_dma_hardware.buffer_bytes_max;
 392
 393         pr_debug("Entered %s\n", __func__);
 394
 395         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 396         buf->dev.dev = pcm->card->dev;
 397         buf->private_data = NULL;
 398         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 399                                            &buf->addr, GFP_KERNEL);
 400         if (!buf->area)
 401                 return -ENOMEM;
 402         buf->bytes = size;
 403         return 0;
 404 }
 405
 406 static void s3c_dma_free_dma_buffers(struct snd_pcm *pcm)
 407 {
 408         struct snd_pcm_substream *substream;
 409         struct snd_dma_buffer *buf;
 410         int stream;
 411
 412         pr_debug("Entered %s\n", __func__);
 413
 414         for (stream = 0; stream < 2; stream++) {
 415                 substream = pcm->streams[stream].substream;
 416                 if (!substream)
 417                         continue;
 418
 419                 buf = &substream->dma_buffer;
 420                 if (!buf->area)
 421                         continue;
 422
 423                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 424                                       buf->area, buf->addr);
 425                 buf->area = NULL;
 426         }
 427 }
 428
 429 static u64 s3c_dma_mask = DMA_BIT_MASK(32);
 430
 431 static int s3c_dma_new(struct snd_card *card,
 432         struct snd_soc_dai *dai, struct snd_pcm *pcm)
 433 {
 434         int ret = 0;
 435
 436         pr_debug("Entered %s\n", __func__);
 437
 438         if (!card->dev->dma_mask)
 439                 card->dev->dma_mask = &s3c_dma_mask;
 440         if (!card->dev->coherent_dma_mask)
 441                 card->dev->coherent_dma_mask = 0xffffffff;
 442
 443         if (dai->playback.channels_min) {
 444                 ret = s3c_preallocate_dma_buffer(pcm,
 445                         SNDRV_PCM_STREAM_PLAYBACK);
 446                 if (ret)
 447                         goto out;
 448         }
 449
 450         if (dai->capture.channels_min) {
 451                 ret = s3c_preallocate_dma_buffer(pcm,
 452                         SNDRV_PCM_STREAM_CAPTURE);
 453                 if (ret)
 454                         goto out;
 455         }
 456  out:
 457         return ret;
 458 }
 459
 460 struct snd_soc_platform s3c24xx_soc_platform = {
 461         .name           = "s3c24xx-audio",
 462         .pcm_ops        = &s3c_dma_ops,
 463         .pcm_new        = s3c_dma_new,
 464         .pcm_free       = s3c_dma_free_dma_buffers,
 465 };
 466 EXPORT_SYMBOL_GPL(s3c24xx_soc_platform);
 467
 468 static int __init s3c24xx_soc_platform_init(void)
 469 {
 470         return snd_soc_register_platform(&s3c24xx_soc_platform);
 471 }
 472 module_init(s3c24xx_soc_platform_init);
 473
 474 static void __exit s3c24xx_soc_platform_exit(void)
 475 {
 476         snd_soc_unregister_platform(&s3c24xx_soc_platform);
 477 }
 478 module_exit(s3c24xx_soc_platform_exit);
 479
 480 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
 481 MODULE_DESCRIPTION("Samsung S3C Audio DMA module");
 482 MODULE_LICENSE("GPL");