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                                     SNDRV_PCM_INFO_PAUSE |
  39                                     SNDRV_PCM_INFO_RESUME,
  40         .formats                = SNDRV_PCM_FMTBIT_S16_LE |
  41                                     SNDRV_PCM_FMTBIT_U16_LE |
  42                                     SNDRV_PCM_FMTBIT_U8 |
  43                                     SNDRV_PCM_FMTBIT_S8,
  44         .channels_min           = 2,
  45         .channels_max           = 2,
  46         .buffer_bytes_max       = 128*1024,
  47         .period_bytes_min       = PAGE_SIZE,
  48         .period_bytes_max       = PAGE_SIZE*2,
  49         .periods_min            = 2,
  50         .periods_max            = 128,
  51         .fifo_size              = 32,
  52 };
  53
  54 struct runtime_data {
  55         spinlock_t lock;
  56         int state;
  57         unsigned int dma_loaded;
  58         unsigned int dma_period;
  59         dma_addr_t dma_start;
  60         dma_addr_t dma_pos;
  61         dma_addr_t dma_end;
  62         struct s3c_dma_params *params;
  63 };
  64
  65 static void audio_buffdone(void *data);
  66
  67 /* dma_enqueue
  68  *
  69  * place a dma buffer onto the queue for the dma system
  70  * to handle.
  71  */
  72 static void dma_enqueue(struct snd_pcm_substream *substream)
  73 {
  74         struct runtime_data *prtd = substream->runtime->private_data;
  75         dma_addr_t pos = prtd->dma_pos;
  76         unsigned int limit;
  77         struct samsung_dma_prep dma_info;
  78
  79         pr_debug("Entered %s\n", __func__);
  80
  81         limit = (prtd->dma_end - prtd->dma_start) / prtd->dma_period;
  82
  83         pr_debug("%s: loaded %d, limit %d\n",
  84                                 __func__, prtd->dma_loaded, limit);
  85
  86         dma_info.cap = (samsung_dma_has_circular() ? DMA_CYCLIC : DMA_SLAVE);
  87         dma_info.direction =
  88                 (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
  89                 ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
  90         dma_info.fp = audio_buffdone;
  91         dma_info.fp_param = substream;
  92         dma_info.period = prtd->dma_period;
  93         dma_info.len = prtd->dma_period*limit;
  94
  95         while (prtd->dma_loaded < limit) {
  96                 pr_debug("dma_loaded: %d\n", prtd->dma_loaded);
  97
  98                 if ((pos + dma_info.period) > prtd->dma_end) {
  99                         dma_info.period  = prtd->dma_end - pos;
 100                         pr_debug("%s: corrected dma len %ld\n",
 101                                         __func__, dma_info.period);
 102                 }
 103
 104                 dma_info.buf = pos;
 105                 prtd->params->ops->prepare(prtd->params->ch, &dma_info);
 106
 107                 prtd->dma_loaded++;
 108                 pos += prtd->dma_period;
 109                 if (pos >= prtd->dma_end)
 110                         pos = prtd->dma_start;
 111         }
 112
 113         prtd->dma_pos = pos;
 114 }
 115
 116 static void audio_buffdone(void *data)
 117 {
 118         struct snd_pcm_substream *substream = data;
 119         struct runtime_data *prtd = substream->runtime->private_data;
 120
 121         pr_debug("Entered %s\n", __func__);
 122
 123         if (prtd->state & ST_RUNNING) {
 124                 prtd->dma_pos += prtd->dma_period;
 125                 if (prtd->dma_pos >= prtd->dma_end)
 126                         prtd->dma_pos = prtd->dma_start;
 127
 128                 if (substream)
 129                         snd_pcm_period_elapsed(substream);
 130
 131                 spin_lock(&prtd->lock);
 132                 if (!samsung_dma_has_circular()) {
 133                         prtd->dma_loaded--;
 134                         dma_enqueue(substream);
 135                 }
 136                 spin_unlock(&prtd->lock);
 137         }
 138 }
 139
 140 static int dma_hw_params(struct snd_pcm_substream *substream,
 141         struct snd_pcm_hw_params *params)
 142 {
 143         struct snd_pcm_runtime *runtime = substream->runtime;
 144         struct runtime_data *prtd = runtime->private_data;
 145         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 146         unsigned long totbytes = params_buffer_bytes(params);
 147         struct s3c_dma_params *dma =
 148                 snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 149         struct samsung_dma_req req;
 150         struct samsung_dma_config config;
 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                 prtd->params->ops = samsung_dma_get_ops();
 169
 170                 req.cap = (samsung_dma_has_circular() ?
 171                         DMA_CYCLIC : DMA_SLAVE);
 172                 req.client = prtd->params->client;
 173                 config.direction =
 174                         (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 175                         ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
 176                 config.width = prtd->params->dma_size;
 177                 config.fifo = prtd->params->dma_addr;
 178                 prtd->params->ch = prtd->params->ops->request(
 179                                 prtd->params->channel, &req);
 180                 prtd->params->ops->config(prtd->params->ch, &config);
 181         }
 182
 183         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 184
 185         runtime->dma_bytes = totbytes;
 186
 187         spin_lock_irq(&prtd->lock);
 188         prtd->dma_loaded = 0;
 189         prtd->dma_period = params_period_bytes(params);
 190         prtd->dma_start = runtime->dma_addr;
 191         prtd->dma_pos = prtd->dma_start;
 192         prtd->dma_end = prtd->dma_start + totbytes;
 193         spin_unlock_irq(&prtd->lock);
 194
 195         return 0;
 196 }
 197
 198 static int dma_hw_free(struct snd_pcm_substream *substream)
 199 {
 200         struct runtime_data *prtd = substream->runtime->private_data;
 201
 202         pr_debug("Entered %s\n", __func__);
 203
 204         snd_pcm_set_runtime_buffer(substream, NULL);
 205
 206         if (prtd->params) {
 207                 prtd->params->ops->flush(prtd->params->ch);
 208                 prtd->params->ops->release(prtd->params->ch,
 209                                         prtd->params->client);
 210                 prtd->params = NULL;
 211         }
 212
 213         return 0;
 214 }
 215
 216 static int dma_prepare(struct snd_pcm_substream *substream)
 217 {
 218         struct runtime_data *prtd = substream->runtime->private_data;
 219         int ret = 0;
 220
 221         pr_debug("Entered %s\n", __func__);
 222
 223         /* return if this is a bufferless transfer e.g.
 224          * codec <--> BT codec or GSM modem -- lg FIXME */
 225         if (!prtd->params)
 226                 return 0;
 227
 228         /* flush the DMA channel */
 229         prtd->params->ops->flush(prtd->params->ch);
 230
 231         prtd->dma_loaded = 0;
 232         prtd->dma_pos = prtd->dma_start;
 233
 234         /* enqueue dma buffers */
 235         dma_enqueue(substream);
 236
 237         return ret;
 238 }
 239
 240 static int dma_trigger(struct snd_pcm_substream *substream, int cmd)
 241 {
 242         struct runtime_data *prtd = substream->runtime->private_data;
 243         int ret = 0;
 244
 245         pr_debug("Entered %s\n", __func__);
 246
 247         spin_lock(&prtd->lock);
 248
 249         switch (cmd) {
 250         case SNDRV_PCM_TRIGGER_START:
 251         case SNDRV_PCM_TRIGGER_RESUME:
 252         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 253                 prtd->state |= ST_RUNNING;
 254                 prtd->params->ops->trigger(prtd->params->ch);
 255                 break;
 256
 257         case SNDRV_PCM_TRIGGER_STOP:
 258         case SNDRV_PCM_TRIGGER_SUSPEND:
 259         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 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 u64 dma_mask = DMA_BIT_MASK(32);
 404
 405 static int dma_new(struct snd_soc_pcm_runtime *rtd)
 406 {
 407         struct snd_card *card = rtd->card->snd_card;
 408         struct snd_pcm *pcm = rtd->pcm;
 409         int ret = 0;
 410
 411         pr_debug("Entered %s\n", __func__);
 412
 413         if (!card->dev->dma_mask)
 414                 card->dev->dma_mask = &dma_mask;
 415         if (!card->dev->coherent_dma_mask)
 416                 card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
 417
 418         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 419                 ret = preallocate_dma_buffer(pcm,
 420                         SNDRV_PCM_STREAM_PLAYBACK);
 421                 if (ret)
 422                         goto out;
 423         }
 424
 425         if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
 426                 ret = preallocate_dma_buffer(pcm,
 427                         SNDRV_PCM_STREAM_CAPTURE);
 428                 if (ret)
 429                         goto out;
 430         }
 431 out:
 432         return ret;
 433 }
 434
 435 static struct snd_soc_platform_driver samsung_asoc_platform = {
 436         .ops            = &dma_ops,
 437         .pcm_new        = dma_new,
 438         .pcm_free       = dma_free_dma_buffers,
 439 };
 440
 441 static int __devinit samsung_asoc_platform_probe(struct platform_device *pdev)
 442 {
 443         return snd_soc_register_platform(&pdev->dev, &samsung_asoc_platform);
 444 }
 445
 446 static int __devexit samsung_asoc_platform_remove(struct platform_device *pdev)
 447 {
 448         snd_soc_unregister_platform(&pdev->dev);
 449         return 0;
 450 }
 451
 452 static struct platform_driver asoc_dma_driver = {
 453         .driver = {
 454                 .name = "samsung-audio",
 455                 .owner = THIS_MODULE,
 456         },
 457
 458         .probe = samsung_asoc_platform_probe,
 459         .remove = __devexit_p(samsung_asoc_platform_remove),
 460 };
 461
 462 module_platform_driver(asoc_dma_driver);
 463
 464 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
 465 MODULE_DESCRIPTION("Samsung ASoC DMA Driver");
 466 MODULE_LICENSE("GPL");
 467 MODULE_ALIAS("platform:samsung-audio");