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                 prtd->params->ops->config(prtd->params->ch, &config);
 180         }
 181
 182         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 183
 184         runtime->dma_bytes = totbytes;
 185
 186         spin_lock_irq(&prtd->lock);
 187         prtd->dma_loaded = 0;
 188         prtd->dma_period = params_period_bytes(params);
 189         prtd->dma_start = runtime->dma_addr;
 190         prtd->dma_pos = prtd->dma_start;
 191         prtd->dma_end = prtd->dma_start + totbytes;
 192         spin_unlock_irq(&prtd->lock);
 193
 194         return 0;
 195 }
 196
 197 static int dma_hw_free(struct snd_pcm_substream *substream)
 198 {
 199         struct runtime_data *prtd = substream->runtime->private_data;
 200
 201         pr_debug("Entered %s\n", __func__);
 202
 203         snd_pcm_set_runtime_buffer(substream, NULL);
 204
 205         if (prtd->params) {
 206                 prtd->params->ops->flush(prtd->params->ch);
 207                 prtd->params->ops->release(prtd->params->ch,
 208                                         prtd->params->client);
 209                 prtd->params = NULL;
 210         }
 211
 212         return 0;
 213 }
 214
 215 static int dma_prepare(struct snd_pcm_substream *substream)
 216 {
 217         struct runtime_data *prtd = substream->runtime->private_data;
 218         int ret = 0;
 219
 220         pr_debug("Entered %s\n", __func__);
 221
 222         /* return if this is a bufferless transfer e.g.
 223          * codec <--> BT codec or GSM modem -- lg FIXME */
 224         if (!prtd->params)
 225                 return 0;
 226
 227         /* flush the DMA channel */
 228         prtd->params->ops->flush(prtd->params->ch);
 229
 230         prtd->dma_loaded = 0;
 231         prtd->dma_pos = prtd->dma_start;
 232
 233         /* enqueue dma buffers */
 234         dma_enqueue(substream);
 235
 236         return ret;
 237 }
 238
 239 static int dma_trigger(struct snd_pcm_substream *substream, int cmd)
 240 {
 241         struct runtime_data *prtd = substream->runtime->private_data;
 242         int ret = 0;
 243
 244         pr_debug("Entered %s\n", __func__);
 245
 246         spin_lock(&prtd->lock);
 247
 248         switch (cmd) {
 249         case SNDRV_PCM_TRIGGER_START:
 250                 prtd->state |= ST_RUNNING;
 251                 prtd->params->ops->trigger(prtd->params->ch);
 252                 break;
 253
 254         case SNDRV_PCM_TRIGGER_STOP:
 255                 prtd->state &= ~ST_RUNNING;
 256                 prtd->params->ops->stop(prtd->params->ch);
 257                 break;
 258
 259         default:
 260                 ret = -EINVAL;
 261                 break;
 262         }
 263
 264         spin_unlock(&prtd->lock);
 265
 266         return ret;
 267 }
 268
 269 static snd_pcm_uframes_t
 270 dma_pointer(struct snd_pcm_substream *substream)
 271 {
 272         struct snd_pcm_runtime *runtime = substream->runtime;
 273         struct runtime_data *prtd = runtime->private_data;
 274         unsigned long res;
 275
 276         pr_debug("Entered %s\n", __func__);
 277
 278         res = prtd->dma_pos - prtd->dma_start;
 279
 280         pr_debug("Pointer offset: %lu\n", res);
 281
 282         /* we seem to be getting the odd error from the pcm library due
 283          * to out-of-bounds pointers. this is maybe due to the dma engine
 284          * not having loaded the new values for the channel before being
 285          * called... (todo - fix )
 286          */
 287
 288         if (res >= snd_pcm_lib_buffer_bytes(substream)) {
 289                 if (res == snd_pcm_lib_buffer_bytes(substream))
 290                         res = 0;
 291         }
 292
 293         return bytes_to_frames(substream->runtime, res);
 294 }
 295
 296 static int dma_open(struct snd_pcm_substream *substream)
 297 {
 298         struct snd_pcm_runtime *runtime = substream->runtime;
 299         struct runtime_data *prtd;
 300
 301         pr_debug("Entered %s\n", __func__);
 302
 303         snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 304         snd_soc_set_runtime_hwparams(substream, &dma_hardware);
 305
 306         prtd = kzalloc(sizeof(struct runtime_data), GFP_KERNEL);
 307         if (prtd == NULL)
 308                 return -ENOMEM;
 309
 310         spin_lock_init(&prtd->lock);
 311
 312         runtime->private_data = prtd;
 313         return 0;
 314 }
 315
 316 static int dma_close(struct snd_pcm_substream *substream)
 317 {
 318         struct snd_pcm_runtime *runtime = substream->runtime;
 319         struct runtime_data *prtd = runtime->private_data;
 320
 321         pr_debug("Entered %s\n", __func__);
 322
 323         if (!prtd)
 324                 pr_debug("dma_close called with prtd == NULL\n");
 325
 326         kfree(prtd);
 327
 328         return 0;
 329 }
 330
 331 static int dma_mmap(struct snd_pcm_substream *substream,
 332         struct vm_area_struct *vma)
 333 {
 334         struct snd_pcm_runtime *runtime = substream->runtime;
 335
 336         pr_debug("Entered %s\n", __func__);
 337
 338         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 339                                      runtime->dma_area,
 340                                      runtime->dma_addr,
 341                                      runtime->dma_bytes);
 342 }
 343
 344 static struct snd_pcm_ops dma_ops = {
 345         .open           = dma_open,
 346         .close          = dma_close,
 347         .ioctl          = snd_pcm_lib_ioctl,
 348         .hw_params      = dma_hw_params,
 349         .hw_free        = dma_hw_free,
 350         .prepare        = dma_prepare,
 351         .trigger        = dma_trigger,
 352         .pointer        = dma_pointer,
 353         .mmap           = dma_mmap,
 354 };
 355
 356 static int preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 357 {
 358         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 359         struct snd_dma_buffer *buf = &substream->dma_buffer;
 360         size_t size = dma_hardware.buffer_bytes_max;
 361
 362         pr_debug("Entered %s\n", __func__);
 363
 364         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 365         buf->dev.dev = pcm->card->dev;
 366         buf->private_data = NULL;
 367         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 368                                            &buf->addr, GFP_KERNEL);
 369         if (!buf->area)
 370                 return -ENOMEM;
 371         buf->bytes = size;
 372         return 0;
 373 }
 374
 375 static void dma_free_dma_buffers(struct snd_pcm *pcm)
 376 {
 377         struct snd_pcm_substream *substream;
 378         struct snd_dma_buffer *buf;
 379         int stream;
 380
 381         pr_debug("Entered %s\n", __func__);
 382
 383         for (stream = 0; stream < 2; stream++) {
 384                 substream = pcm->streams[stream].substream;
 385                 if (!substream)
 386                         continue;
 387
 388                 buf = &substream->dma_buffer;
 389                 if (!buf->area)
 390                         continue;
 391
 392                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 393                                       buf->area, buf->addr);
 394                 buf->area = NULL;
 395         }
 396 }
 397
 398 static u64 dma_mask = DMA_BIT_MASK(32);
 399
 400 static int dma_new(struct snd_soc_pcm_runtime *rtd)
 401 {
 402         struct snd_card *card = rtd->card->snd_card;
 403         struct snd_pcm *pcm = rtd->pcm;
 404         int ret = 0;
 405
 406         pr_debug("Entered %s\n", __func__);
 407
 408         if (!card->dev->dma_mask)
 409                 card->dev->dma_mask = &dma_mask;
 410         if (!card->dev->coherent_dma_mask)
 411                 card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
 412
 413         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 414                 ret = preallocate_dma_buffer(pcm,
 415                         SNDRV_PCM_STREAM_PLAYBACK);
 416                 if (ret)
 417                         goto out;
 418         }
 419
 420         if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
 421                 ret = preallocate_dma_buffer(pcm,
 422                         SNDRV_PCM_STREAM_CAPTURE);
 423                 if (ret)
 424                         goto out;
 425         }
 426 out:
 427         return ret;
 428 }
 429
 430 static struct snd_soc_platform_driver samsung_asoc_platform = {
 431         .ops            = &dma_ops,
 432         .pcm_new        = dma_new,
 433         .pcm_free       = dma_free_dma_buffers,
 434 };
 435
 436 int asoc_dma_platform_register(struct device *dev)
 437 {
 438         return snd_soc_register_platform(dev, &samsung_asoc_platform);
 439 }
 440 EXPORT_SYMBOL_GPL(asoc_dma_platform_register);
 441
 442 void asoc_dma_platform_unregister(struct device *dev)
 443 {
 444         snd_soc_unregister_platform(dev);
 445 }
 446 EXPORT_SYMBOL_GPL(asoc_dma_platform_unregister);
 447
 448 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
 449 MODULE_DESCRIPTION("Samsung ASoC DMA Driver");
 450 MODULE_LICENSE("GPL");