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         .formats                = SNDRV_PCM_FMTBIT_S16_LE |
  39                                     SNDRV_PCM_FMTBIT_U16_LE |
  40                                     SNDRV_PCM_FMTBIT_U8 |
  41                                     SNDRV_PCM_FMTBIT_S8,
  42         .channels_min           = 2,
  43         .channels_max           = 2,
  44         .buffer_bytes_max       = 128*1024,
  45         .period_bytes_min       = PAGE_SIZE,
  46         .period_bytes_max       = PAGE_SIZE*2,
  47         .periods_min            = 2,
  48         .periods_max            = 128,
  49         .fifo_size              = 32,
  50 };
  51
  52 struct runtime_data {
  53         spinlock_t lock;
  54         int state;
  55         unsigned int dma_loaded;
  56         unsigned int dma_period;
  57         dma_addr_t dma_start;
  58         dma_addr_t dma_pos;
  59         dma_addr_t dma_end;
  60         struct s3c_dma_params *params;
  61 };
  62
  63 static void audio_buffdone(void *data);
  64
  65 /* dma_enqueue
  66  *
  67  * place a dma buffer onto the queue for the dma system
  68  * to handle.
  69  */
  70 static void dma_enqueue(struct snd_pcm_substream *substream)
  71 {
  72         struct runtime_data *prtd = substream->runtime->private_data;
  73         dma_addr_t pos = prtd->dma_pos;
  74         unsigned int limit;
  75         struct samsung_dma_prep dma_info;
  76
  77         pr_debug("Entered %s\n", __func__);
  78
  79         limit = (prtd->dma_end - prtd->dma_start) / prtd->dma_period;
  80
  81         pr_debug("%s: loaded %d, limit %d\n",
  82                                 __func__, prtd->dma_loaded, limit);
  83
  84         dma_info.cap = (samsung_dma_has_circular() ? DMA_CYCLIC : DMA_SLAVE);
  85         dma_info.direction =
  86                 (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
  87                 ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
  88         dma_info.fp = audio_buffdone;
  89         dma_info.fp_param = substream;
  90         dma_info.period = prtd->dma_period;
  91         dma_info.len = prtd->dma_period*limit;
  92
  93         while (prtd->dma_loaded < limit) {
  94                 pr_debug("dma_loaded: %d\n", prtd->dma_loaded);
  95
  96                 if ((pos + dma_info.period) > prtd->dma_end) {
  97                         dma_info.period  = prtd->dma_end - pos;
  98                         pr_debug("%s: corrected dma len %ld\n",
  99                                         __func__, dma_info.period);
 100                 }
 101
 102                 dma_info.buf = pos;
 103                 prtd->params->ops->prepare(prtd->params->ch, &dma_info);
 104
 105                 prtd->dma_loaded++;
 106                 pos += prtd->dma_period;
 107                 if (pos >= prtd->dma_end)
 108                         pos = prtd->dma_start;
 109         }
 110
 111         prtd->dma_pos = pos;
 112 }
 113
 114 static void audio_buffdone(void *data)
 115 {
 116         struct snd_pcm_substream *substream = data;
 117         struct runtime_data *prtd = substream->runtime->private_data;
 118
 119         pr_debug("Entered %s\n", __func__);
 120
 121         if (prtd->state & ST_RUNNING) {
 122                 prtd->dma_pos += prtd->dma_period;
 123                 if (prtd->dma_pos >= prtd->dma_end)
 124                         prtd->dma_pos = prtd->dma_start;
 125
 126                 if (substream)
 127                         snd_pcm_period_elapsed(substream);
 128
 129                 spin_lock(&prtd->lock);
 130                 if (!samsung_dma_has_circular()) {
 131                         prtd->dma_loaded--;
 132                         dma_enqueue(substream);
 133                 }
 134                 spin_unlock(&prtd->lock);
 135         }
 136 }
 137
 138 static int dma_hw_params(struct snd_pcm_substream *substream,
 139         struct snd_pcm_hw_params *params)
 140 {
 141         struct snd_pcm_runtime *runtime = substream->runtime;
 142         struct runtime_data *prtd = runtime->private_data;
 143         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 144         unsigned long totbytes = params_buffer_bytes(params);
 145         struct s3c_dma_params *dma =
 146                 snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 147         struct samsung_dma_req req;
 148         struct samsung_dma_config config;
 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                 req.cap = (samsung_dma_has_circular() ?
 169                         DMA_CYCLIC : DMA_SLAVE);
 170                 req.client = prtd->params->client;
 171                 config.direction =
 172                         (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 173                         ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
 174                 config.width = prtd->params->dma_size;
 175                 config.fifo = prtd->params->dma_addr;
 176                 prtd->params->ch = prtd->params->ops->request(
 177                                 prtd->params->channel, &req, rtd->cpu_dai->dev,
 178                                 prtd->params->ch_name);
 179                 if (!prtd->params->ch) {
 180                         pr_err("Failed to allocate DMA channel\n");
 181                         return -ENXIO;
 182                 }
 183                 prtd->params->ops->config(prtd->params->ch, &config);
 184         }
 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_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 dma_hw_free(struct snd_pcm_substream *substream)
 202 {
 203         struct runtime_data *prtd = substream->runtime->private_data;
 204
 205         pr_debug("Entered %s\n", __func__);
 206
 207         snd_pcm_set_runtime_buffer(substream, NULL);
 208
 209         if (prtd->params) {
 210                 prtd->params->ops->flush(prtd->params->ch);
 211                 prtd->params->ops->release(prtd->params->ch,
 212                                         prtd->params->client);
 213                 prtd->params = NULL;
 214         }
 215
 216         return 0;
 217 }
 218
 219 static int dma_prepare(struct snd_pcm_substream *substream)
 220 {
 221         struct 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         /* flush the DMA channel */
 232         prtd->params->ops->flush(prtd->params->ch);
 233
 234         prtd->dma_loaded = 0;
 235         prtd->dma_pos = prtd->dma_start;
 236
 237         /* enqueue dma buffers */
 238         dma_enqueue(substream);
 239
 240         return ret;
 241 }
 242
 243 static int dma_trigger(struct snd_pcm_substream *substream, int cmd)
 244 {
 245         struct runtime_data *prtd = substream->runtime->private_data;
 246         int ret = 0;
 247
 248         pr_debug("Entered %s\n", __func__);
 249
 250         spin_lock(&prtd->lock);
 251
 252         switch (cmd) {
 253         case SNDRV_PCM_TRIGGER_START:
 254                 prtd->state |= ST_RUNNING;
 255                 prtd->params->ops->trigger(prtd->params->ch);
 256                 break;
 257
 258         case SNDRV_PCM_TRIGGER_STOP:
 259                 prtd->state &= ~ST_RUNNING;
 260                 prtd->params->ops->stop(prtd->params->ch);
 261                 break;
 262
 263         default:
 264                 ret = -EINVAL;
 265                 break;
 266         }
 267
 268         spin_unlock(&prtd->lock);
 269
 270         return ret;
 271 }
 272
 273 static snd_pcm_uframes_t
 274 dma_pointer(struct snd_pcm_substream *substream)
 275 {
 276         struct snd_pcm_runtime *runtime = substream->runtime;
 277         struct runtime_data *prtd = runtime->private_data;
 278         unsigned long res;
 279
 280         pr_debug("Entered %s\n", __func__);
 281
 282         res = prtd->dma_pos - prtd->dma_start;
 283
 284         pr_debug("Pointer offset: %lu\n", res);
 285
 286         /* we seem to be getting the odd error from the pcm library due
 287          * to out-of-bounds pointers. this is maybe due to the dma engine
 288          * not having loaded the new values for the channel before being
 289          * called... (todo - fix )
 290          */
 291
 292         if (res >= snd_pcm_lib_buffer_bytes(substream)) {
 293                 if (res == snd_pcm_lib_buffer_bytes(substream))
 294                         res = 0;
 295         }
 296
 297         return bytes_to_frames(substream->runtime, res);
 298 }
 299
 300 static int dma_open(struct snd_pcm_substream *substream)
 301 {
 302         struct snd_pcm_runtime *runtime = substream->runtime;
 303         struct runtime_data *prtd;
 304
 305         pr_debug("Entered %s\n", __func__);
 306
 307         snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 308         snd_soc_set_runtime_hwparams(substream, &dma_hardware);
 309
 310         prtd = kzalloc(sizeof(struct runtime_data), GFP_KERNEL);
 311         if (prtd == NULL)
 312                 return -ENOMEM;
 313
 314         spin_lock_init(&prtd->lock);
 315
 316         runtime->private_data = prtd;
 317         return 0;
 318 }
 319
 320 static int dma_close(struct snd_pcm_substream *substream)
 321 {
 322         struct snd_pcm_runtime *runtime = substream->runtime;
 323         struct runtime_data *prtd = runtime->private_data;
 324
 325         pr_debug("Entered %s\n", __func__);
 326
 327         if (!prtd)
 328                 pr_debug("dma_close called with prtd == NULL\n");
 329
 330         kfree(prtd);
 331
 332         return 0;
 333 }
 334
 335 static int dma_mmap(struct snd_pcm_substream *substream,
 336         struct vm_area_struct *vma)
 337 {
 338         struct snd_pcm_runtime *runtime = substream->runtime;
 339
 340         pr_debug("Entered %s\n", __func__);
 341
 342         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 343                                      runtime->dma_area,
 344                                      runtime->dma_addr,
 345                                      runtime->dma_bytes);
 346 }
 347
 348 static struct snd_pcm_ops dma_ops = {
 349         .open           = dma_open,
 350         .close          = dma_close,
 351         .ioctl          = snd_pcm_lib_ioctl,
 352         .hw_params      = dma_hw_params,
 353         .hw_free        = dma_hw_free,
 354         .prepare        = dma_prepare,
 355         .trigger        = dma_trigger,
 356         .pointer        = dma_pointer,
 357         .mmap           = dma_mmap,
 358 };
 359
 360 static int preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 361 {
 362         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 363         struct snd_dma_buffer *buf = &substream->dma_buffer;
 364         size_t size = dma_hardware.buffer_bytes_max;
 365
 366         pr_debug("Entered %s\n", __func__);
 367
 368         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 369         buf->dev.dev = pcm->card->dev;
 370         buf->private_data = NULL;
 371         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 372                                            &buf->addr, GFP_KERNEL);
 373         if (!buf->area)
 374                 return -ENOMEM;
 375         buf->bytes = size;
 376         return 0;
 377 }
 378
 379 static void dma_free_dma_buffers(struct snd_pcm *pcm)
 380 {
 381         struct snd_pcm_substream *substream;
 382         struct snd_dma_buffer *buf;
 383         int stream;
 384
 385         pr_debug("Entered %s\n", __func__);
 386
 387         for (stream = 0; stream < 2; stream++) {
 388                 substream = pcm->streams[stream].substream;
 389                 if (!substream)
 390                         continue;
 391
 392                 buf = &substream->dma_buffer;
 393                 if (!buf->area)
 394                         continue;
 395
 396                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 397                                       buf->area, buf->addr);
 398                 buf->area = NULL;
 399         }
 400 }
 401
 402 static u64 dma_mask = DMA_BIT_MASK(32);
 403
 404 static int dma_new(struct snd_soc_pcm_runtime *rtd)
 405 {
 406         struct snd_card *card = rtd->card->snd_card;
 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 = DMA_BIT_MASK(32);
 416
 417         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 418                 ret = preallocate_dma_buffer(pcm,
 419                         SNDRV_PCM_STREAM_PLAYBACK);
 420                 if (ret)
 421                         goto out;
 422         }
 423
 424         if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
 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 int samsung_asoc_dma_platform_register(struct device *dev)
 441 {
 442         return snd_soc_register_platform(dev, &samsung_asoc_platform);
 443 }
 444 EXPORT_SYMBOL_GPL(samsung_asoc_dma_platform_register);
 445
 446 void samsung_asoc_dma_platform_unregister(struct device *dev)
 447 {
 448         snd_soc_unregister_platform(dev);
 449 }
 450 EXPORT_SYMBOL_GPL(samsung_asoc_dma_platform_unregister);
 451
 452 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
 453 MODULE_DESCRIPTION("Samsung ASoC DMA Driver");
 454 MODULE_LICENSE("GPL");