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         .buffer_bytes_max       = 128*1024,
  39         .period_bytes_min       = PAGE_SIZE,
  40         .period_bytes_max       = PAGE_SIZE*2,
  41         .periods_min            = 2,
  42         .periods_max            = 128,
  43         .fifo_size              = 32,
  44 };
  45
  46 struct runtime_data {
  47         spinlock_t lock;
  48         int state;
  49         unsigned int dma_loaded;
  50         unsigned int dma_period;
  51         dma_addr_t dma_start;
  52         dma_addr_t dma_pos;
  53         dma_addr_t dma_end;
  54         struct s3c_dma_params *params;
  55 };
  56
  57 static void audio_buffdone(void *data);
  58
  59 /* dma_enqueue
  60  *
  61  * place a dma buffer onto the queue for the dma system
  62  * to handle.
  63  */
  64 static void dma_enqueue(struct snd_pcm_substream *substream)
  65 {
  66         struct runtime_data *prtd = substream->runtime->private_data;
  67         dma_addr_t pos = prtd->dma_pos;
  68         unsigned int limit;
  69         struct samsung_dma_prep dma_info;
  70
  71         pr_debug("Entered %s\n", __func__);
  72
  73         limit = (prtd->dma_end - prtd->dma_start) / prtd->dma_period;
  74
  75         pr_debug("%s: loaded %d, limit %d\n",
  76                                 __func__, prtd->dma_loaded, limit);
  77
  78         dma_info.cap = (samsung_dma_has_circular() ? DMA_CYCLIC : DMA_SLAVE);
  79         dma_info.direction =
  80                 (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
  81                 ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
  82         dma_info.fp = audio_buffdone;
  83         dma_info.fp_param = substream;
  84         dma_info.period = prtd->dma_period;
  85         dma_info.len = prtd->dma_period*limit;
  86
  87         if (dma_info.cap == DMA_CYCLIC) {
  88                 dma_info.buf = pos;
  89                 prtd->params->ops->prepare(prtd->params->ch, &dma_info);
  90                 prtd->dma_loaded += limit;
  91                 return;
  92         }
  93
  94         while (prtd->dma_loaded < limit) {
  95                 pr_debug("dma_loaded: %d\n", prtd->dma_loaded);
  96
  97                 if ((pos + dma_info.period) > prtd->dma_end) {
  98                         dma_info.period  = prtd->dma_end - pos;
  99                         pr_debug("%s: corrected dma len %ld\n",
 100                                         __func__, dma_info.period);
 101                 }
 102
 103                 dma_info.buf = pos;
 104                 prtd->params->ops->prepare(prtd->params->ch, &dma_info);
 105
 106                 prtd->dma_loaded++;
 107                 pos += prtd->dma_period;
 108                 if (pos >= prtd->dma_end)
 109                         pos = prtd->dma_start;
 110         }
 111
 112         prtd->dma_pos = pos;
 113 }
 114
 115 static void audio_buffdone(void *data)
 116 {
 117         struct snd_pcm_substream *substream = data;
 118         struct runtime_data *prtd = substream->runtime->private_data;
 119
 120         pr_debug("Entered %s\n", __func__);
 121
 122         if (prtd->state & ST_RUNNING) {
 123                 prtd->dma_pos += prtd->dma_period;
 124                 if (prtd->dma_pos >= prtd->dma_end)
 125                         prtd->dma_pos = prtd->dma_start;
 126
 127                 if (substream)
 128                         snd_pcm_period_elapsed(substream);
 129
 130                 spin_lock(&prtd->lock);
 131                 if (!samsung_dma_has_circular()) {
 132                         prtd->dma_loaded--;
 133                         dma_enqueue(substream);
 134                 }
 135                 spin_unlock(&prtd->lock);
 136         }
 137 }
 138
 139 static int dma_hw_params(struct snd_pcm_substream *substream,
 140         struct snd_pcm_hw_params *params)
 141 {
 142         struct snd_pcm_runtime *runtime = substream->runtime;
 143         struct runtime_data *prtd = runtime->private_data;
 144         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 145         unsigned long totbytes = params_buffer_bytes(params);
 146         struct s3c_dma_params *dma =
 147                 snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 148         struct samsung_dma_req req;
 149         struct samsung_dma_config config;
 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                 req.cap = (samsung_dma_has_circular() ?
 170                         DMA_CYCLIC : DMA_SLAVE);
 171                 req.client = prtd->params->client;
 172                 config.direction =
 173                         (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 174                         ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
 175                 config.width = prtd->params->dma_size;
 176                 config.fifo = prtd->params->dma_addr;
 177                 prtd->params->ch = prtd->params->ops->request(
 178                                 prtd->params->channel, &req, rtd->cpu_dai->dev,
 179                                 prtd->params->ch_name);
 180                 if (!prtd->params->ch) {
 181                         pr_err("Failed to allocate DMA channel\n");
 182                         return -ENXIO;
 183                 }
 184                 prtd->params->ops->config(prtd->params->ch, &config);
 185         }
 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_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 dma_hw_free(struct snd_pcm_substream *substream)
 203 {
 204         struct runtime_data *prtd = substream->runtime->private_data;
 205
 206         pr_debug("Entered %s\n", __func__);
 207
 208         snd_pcm_set_runtime_buffer(substream, NULL);
 209
 210         if (prtd->params) {
 211                 prtd->params->ops->flush(prtd->params->ch);
 212                 prtd->params->ops->release(prtd->params->ch,
 213                                         prtd->params->client);
 214                 prtd->params = NULL;
 215         }
 216
 217         return 0;
 218 }
 219
 220 static int dma_prepare(struct snd_pcm_substream *substream)
 221 {
 222         struct 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         /* flush the DMA channel */
 233         prtd->params->ops->flush(prtd->params->ch);
 234
 235         prtd->dma_loaded = 0;
 236         prtd->dma_pos = prtd->dma_start;
 237
 238         /* enqueue dma buffers */
 239         dma_enqueue(substream);
 240
 241         return ret;
 242 }
 243
 244 static int dma_trigger(struct snd_pcm_substream *substream, int cmd)
 245 {
 246         struct runtime_data *prtd = substream->runtime->private_data;
 247         int ret = 0;
 248
 249         pr_debug("Entered %s\n", __func__);
 250
 251         spin_lock(&prtd->lock);
 252
 253         switch (cmd) {
 254         case SNDRV_PCM_TRIGGER_START:
 255                 prtd->state |= ST_RUNNING;
 256                 prtd->params->ops->trigger(prtd->params->ch);
 257                 break;
 258
 259         case SNDRV_PCM_TRIGGER_STOP:
 260                 prtd->state &= ~ST_RUNNING;
 261                 prtd->params->ops->stop(prtd->params->ch);
 262                 break;
 263
 264         default:
 265                 ret = -EINVAL;
 266                 break;
 267         }
 268
 269         spin_unlock(&prtd->lock);
 270
 271         return ret;
 272 }
 273
 274 static snd_pcm_uframes_t
 275 dma_pointer(struct snd_pcm_substream *substream)
 276 {
 277         struct snd_pcm_runtime *runtime = substream->runtime;
 278         struct runtime_data *prtd = runtime->private_data;
 279         unsigned long res;
 280
 281         pr_debug("Entered %s\n", __func__);
 282
 283         res = prtd->dma_pos - prtd->dma_start;
 284
 285         pr_debug("Pointer offset: %lu\n", res);
 286
 287         /* we seem to be getting the odd error from the pcm library due
 288          * to out-of-bounds pointers. this is maybe due to the dma engine
 289          * not having loaded the new values for the channel before being
 290          * called... (todo - fix )
 291          */
 292
 293         if (res >= snd_pcm_lib_buffer_bytes(substream)) {
 294                 if (res == snd_pcm_lib_buffer_bytes(substream))
 295                         res = 0;
 296         }
 297
 298         return bytes_to_frames(substream->runtime, res);
 299 }
 300
 301 static int dma_open(struct snd_pcm_substream *substream)
 302 {
 303         struct snd_pcm_runtime *runtime = substream->runtime;
 304         struct runtime_data *prtd;
 305
 306         pr_debug("Entered %s\n", __func__);
 307
 308         snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 309         snd_soc_set_runtime_hwparams(substream, &dma_hardware);
 310
 311         prtd = kzalloc(sizeof(struct runtime_data), GFP_KERNEL);
 312         if (prtd == NULL)
 313                 return -ENOMEM;
 314
 315         spin_lock_init(&prtd->lock);
 316
 317         runtime->private_data = prtd;
 318         return 0;
 319 }
 320
 321 static int dma_close(struct snd_pcm_substream *substream)
 322 {
 323         struct snd_pcm_runtime *runtime = substream->runtime;
 324         struct runtime_data *prtd = runtime->private_data;
 325
 326         pr_debug("Entered %s\n", __func__);
 327
 328         if (!prtd)
 329                 pr_debug("dma_close called with prtd == NULL\n");
 330
 331         kfree(prtd);
 332
 333         return 0;
 334 }
 335
 336 static int dma_mmap(struct snd_pcm_substream *substream,
 337         struct vm_area_struct *vma)
 338 {
 339         struct snd_pcm_runtime *runtime = substream->runtime;
 340
 341         pr_debug("Entered %s\n", __func__);
 342
 343         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 344                                      runtime->dma_area,
 345                                      runtime->dma_addr,
 346                                      runtime->dma_bytes);
 347 }
 348
 349 static struct snd_pcm_ops dma_ops = {
 350         .open           = dma_open,
 351         .close          = dma_close,
 352         .ioctl          = snd_pcm_lib_ioctl,
 353         .hw_params      = dma_hw_params,
 354         .hw_free        = dma_hw_free,
 355         .prepare        = dma_prepare,
 356         .trigger        = dma_trigger,
 357         .pointer        = dma_pointer,
 358         .mmap           = dma_mmap,
 359 };
 360
 361 static int preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 362 {
 363         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 364         struct snd_dma_buffer *buf = &substream->dma_buffer;
 365         size_t size = dma_hardware.buffer_bytes_max;
 366
 367         pr_debug("Entered %s\n", __func__);
 368
 369         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 370         buf->dev.dev = pcm->card->dev;
 371         buf->private_data = NULL;
 372         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 373                                            &buf->addr, GFP_KERNEL);
 374         if (!buf->area)
 375                 return -ENOMEM;
 376         buf->bytes = size;
 377         return 0;
 378 }
 379
 380 static void dma_free_dma_buffers(struct snd_pcm *pcm)
 381 {
 382         struct snd_pcm_substream *substream;
 383         struct snd_dma_buffer *buf;
 384         int stream;
 385
 386         pr_debug("Entered %s\n", __func__);
 387
 388         for (stream = 0; stream < 2; stream++) {
 389                 substream = pcm->streams[stream].substream;
 390                 if (!substream)
 391                         continue;
 392
 393                 buf = &substream->dma_buffer;
 394                 if (!buf->area)
 395                         continue;
 396
 397                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 398                                       buf->area, buf->addr);
 399                 buf->area = NULL;
 400         }
 401 }
 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_pcm *pcm = rtd->pcm;
 407         int ret;
 408
 409         pr_debug("Entered %s\n", __func__);
 410
 411         ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
 412         if (ret)
 413                 return ret;
 414
 415         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 416                 ret = preallocate_dma_buffer(pcm,
 417                         SNDRV_PCM_STREAM_PLAYBACK);
 418                 if (ret)
 419                         goto out;
 420         }
 421
 422         if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
 423                 ret = preallocate_dma_buffer(pcm,
 424                         SNDRV_PCM_STREAM_CAPTURE);
 425                 if (ret)
 426                         goto out;
 427         }
 428 out:
 429         return ret;
 430 }
 431
 432 static struct snd_soc_platform_driver samsung_asoc_platform = {
 433         .ops            = &dma_ops,
 434         .pcm_new        = dma_new,
 435         .pcm_free       = dma_free_dma_buffers,
 436 };
 437
 438 void samsung_asoc_init_dma_data(struct snd_soc_dai *dai,
 439                                 struct s3c_dma_params *playback,
 440                                 struct s3c_dma_params *capture)
 441 {
 442         snd_soc_dai_init_dma_data(dai, playback, capture);
 443 }
 444 EXPORT_SYMBOL_GPL(samsung_asoc_init_dma_data);
 445
 446 int samsung_asoc_dma_platform_register(struct device *dev)
 447 {
 448         return devm_snd_soc_register_platform(dev, &samsung_asoc_platform);
 449 }
 450 EXPORT_SYMBOL_GPL(samsung_asoc_dma_platform_register);
 451
 452 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
 453 MODULE_DESCRIPTION("Samsung ASoC DMA Driver");
 454 MODULE_LICENSE("GPL");