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);
 178                 prtd->params->ops->config(prtd->params->ch, &config);
 179         }
 180
 181         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 182
 183         runtime->dma_bytes = totbytes;
 184
 185         spin_lock_irq(&prtd->lock);
 186         prtd->dma_loaded = 0;
 187         prtd->dma_period = params_period_bytes(params);
 188         prtd->dma_start = runtime->dma_addr;
 189         prtd->dma_pos = prtd->dma_start;
 190         prtd->dma_end = prtd->dma_start + totbytes;
 191         spin_unlock_irq(&prtd->lock);
 192
 193         return 0;
 194 }
 195
 196 static int dma_hw_free(struct snd_pcm_substream *substream)
 197 {
 198         struct runtime_data *prtd = substream->runtime->private_data;
 199
 200         pr_debug("Entered %s\n", __func__);
 201
 202         snd_pcm_set_runtime_buffer(substream, NULL);
 203
 204         if (prtd->params) {
 205                 prtd->params->ops->flush(prtd->params->ch);
 206                 prtd->params->ops->release(prtd->params->ch,
 207                                         prtd->params->client);
 208                 prtd->params = NULL;
 209         }
 210
 211         return 0;
 212 }
 213
 214 static int dma_prepare(struct snd_pcm_substream *substream)
 215 {
 216         struct runtime_data *prtd = substream->runtime->private_data;
 217         int ret = 0;
 218
 219         pr_debug("Entered %s\n", __func__);
 220
 221         /* return if this is a bufferless transfer e.g.
 222          * codec <--> BT codec or GSM modem -- lg FIXME */
 223         if (!prtd->params)
 224                 return 0;
 225
 226         /* flush the DMA channel */
 227         prtd->params->ops->flush(prtd->params->ch);
 228
 229         prtd->dma_loaded = 0;
 230         prtd->dma_pos = prtd->dma_start;
 231
 232         /* enqueue dma buffers */
 233         dma_enqueue(substream);
 234
 235         return ret;
 236 }
 237
 238 static int dma_trigger(struct snd_pcm_substream *substream, int cmd)
 239 {
 240         struct runtime_data *prtd = substream->runtime->private_data;
 241         int ret = 0;
 242
 243         pr_debug("Entered %s\n", __func__);
 244
 245         spin_lock(&prtd->lock);
 246
 247         switch (cmd) {
 248         case SNDRV_PCM_TRIGGER_START:
 249                 prtd->state |= ST_RUNNING;
 250                 prtd->params->ops->trigger(prtd->params->ch);
 251                 break;
 252
 253         case SNDRV_PCM_TRIGGER_STOP:
 254                 prtd->state &= ~ST_RUNNING;
 255                 prtd->params->ops->stop(prtd->params->ch);
 256                 break;
 257
 258         default:
 259                 ret = -EINVAL;
 260                 break;
 261         }
 262
 263         spin_unlock(&prtd->lock);
 264
 265         return ret;
 266 }
 267
 268 static snd_pcm_uframes_t
 269 dma_pointer(struct snd_pcm_substream *substream)
 270 {
 271         struct snd_pcm_runtime *runtime = substream->runtime;
 272         struct runtime_data *prtd = runtime->private_data;
 273         unsigned long res;
 274
 275         pr_debug("Entered %s\n", __func__);
 276
 277         res = prtd->dma_pos - prtd->dma_start;
 278
 279         pr_debug("Pointer offset: %lu\n", res);
 280
 281         /* we seem to be getting the odd error from the pcm library due
 282          * to out-of-bounds pointers. this is maybe due to the dma engine
 283          * not having loaded the new values for the channel before being
 284          * called... (todo - fix )
 285          */
 286
 287         if (res >= snd_pcm_lib_buffer_bytes(substream)) {
 288                 if (res == snd_pcm_lib_buffer_bytes(substream))
 289                         res = 0;
 290         }
 291
 292         return bytes_to_frames(substream->runtime, res);
 293 }
 294
 295 static int dma_open(struct snd_pcm_substream *substream)
 296 {
 297         struct snd_pcm_runtime *runtime = substream->runtime;
 298         struct runtime_data *prtd;
 299
 300         pr_debug("Entered %s\n", __func__);
 301
 302         snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 303         snd_soc_set_runtime_hwparams(substream, &dma_hardware);
 304
 305         prtd = kzalloc(sizeof(struct runtime_data), GFP_KERNEL);
 306         if (prtd == NULL)
 307                 return -ENOMEM;
 308
 309         spin_lock_init(&prtd->lock);
 310
 311         runtime->private_data = prtd;
 312         return 0;
 313 }
 314
 315 static int dma_close(struct snd_pcm_substream *substream)
 316 {
 317         struct snd_pcm_runtime *runtime = substream->runtime;
 318         struct runtime_data *prtd = runtime->private_data;
 319
 320         pr_debug("Entered %s\n", __func__);
 321
 322         if (!prtd)
 323                 pr_debug("dma_close called with prtd == NULL\n");
 324
 325         kfree(prtd);
 326
 327         return 0;
 328 }
 329
 330 static int dma_mmap(struct snd_pcm_substream *substream,
 331         struct vm_area_struct *vma)
 332 {
 333         struct snd_pcm_runtime *runtime = substream->runtime;
 334
 335         pr_debug("Entered %s\n", __func__);
 336
 337         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 338                                      runtime->dma_area,
 339                                      runtime->dma_addr,
 340                                      runtime->dma_bytes);
 341 }
 342
 343 static struct snd_pcm_ops dma_ops = {
 344         .open           = dma_open,
 345         .close          = dma_close,
 346         .ioctl          = snd_pcm_lib_ioctl,
 347         .hw_params      = dma_hw_params,
 348         .hw_free        = dma_hw_free,
 349         .prepare        = dma_prepare,
 350         .trigger        = dma_trigger,
 351         .pointer        = dma_pointer,
 352         .mmap           = dma_mmap,
 353 };
 354
 355 static int preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 356 {
 357         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 358         struct snd_dma_buffer *buf = &substream->dma_buffer;
 359         size_t size = dma_hardware.buffer_bytes_max;
 360
 361         pr_debug("Entered %s\n", __func__);
 362
 363         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 364         buf->dev.dev = pcm->card->dev;
 365         buf->private_data = NULL;
 366         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 367                                            &buf->addr, GFP_KERNEL);
 368         if (!buf->area)
 369                 return -ENOMEM;
 370         buf->bytes = size;
 371         return 0;
 372 }
 373
 374 static void dma_free_dma_buffers(struct snd_pcm *pcm)
 375 {
 376         struct snd_pcm_substream *substream;
 377         struct snd_dma_buffer *buf;
 378         int stream;
 379
 380         pr_debug("Entered %s\n", __func__);
 381
 382         for (stream = 0; stream < 2; stream++) {
 383                 substream = pcm->streams[stream].substream;
 384                 if (!substream)
 385                         continue;
 386
 387                 buf = &substream->dma_buffer;
 388                 if (!buf->area)
 389                         continue;
 390
 391                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 392                                       buf->area, buf->addr);
 393                 buf->area = NULL;
 394         }
 395 }
 396
 397 static u64 dma_mask = DMA_BIT_MASK(32);
 398
 399 static int dma_new(struct snd_soc_pcm_runtime *rtd)
 400 {
 401         struct snd_card *card = rtd->card->snd_card;
 402         struct snd_pcm *pcm = rtd->pcm;
 403         int ret = 0;
 404
 405         pr_debug("Entered %s\n", __func__);
 406
 407         if (!card->dev->dma_mask)
 408                 card->dev->dma_mask = &dma_mask;
 409         if (!card->dev->coherent_dma_mask)
 410                 card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
 411
 412         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 413                 ret = preallocate_dma_buffer(pcm,
 414                         SNDRV_PCM_STREAM_PLAYBACK);
 415                 if (ret)
 416                         goto out;
 417         }
 418
 419         if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
 420                 ret = preallocate_dma_buffer(pcm,
 421                         SNDRV_PCM_STREAM_CAPTURE);
 422                 if (ret)
 423                         goto out;
 424         }
 425 out:
 426         return ret;
 427 }
 428
 429 static struct snd_soc_platform_driver samsung_asoc_platform = {
 430         .ops            = &dma_ops,
 431         .pcm_new        = dma_new,
 432         .pcm_free       = dma_free_dma_buffers,
 433 };
 434
 435 int asoc_dma_platform_register(struct device *dev)
 436 {
 437         return snd_soc_register_platform(dev, &samsung_asoc_platform);
 438 }
 439 EXPORT_SYMBOL_GPL(asoc_dma_platform_register);
 440
 441 void asoc_dma_platform_unregister(struct device *dev)
 442 {
 443         snd_soc_unregister_platform(dev);
 444 }
 445 EXPORT_SYMBOL_GPL(asoc_dma_platform_unregister);
 446
 447 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
 448 MODULE_DESCRIPTION("Samsung ASoC DMA Driver");
 449 MODULE_LICENSE("GPL");