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         if (dma_info.cap == DMA_CYCLIC) {
  94                 dma_info.buf = pos;
  95                 prtd->params->ops->prepare(prtd->params->ch, &dma_info);
  96                 prtd->dma_loaded += limit;
  97                 return;
  98         }
  99
 100         while (prtd->dma_loaded < limit) {
 101                 pr_debug("dma_loaded: %d\n", prtd->dma_loaded);
 102
 103                 if ((pos + dma_info.period) > prtd->dma_end) {
 104                         dma_info.period  = prtd->dma_end - pos;
 105                         pr_debug("%s: corrected dma len %ld\n",
 106                                         __func__, dma_info.period);
 107                 }
 108
 109                 dma_info.buf = pos;
 110                 prtd->params->ops->prepare(prtd->params->ch, &dma_info);
 111
 112                 prtd->dma_loaded++;
 113                 pos += prtd->dma_period;
 114                 if (pos >= prtd->dma_end)
 115                         pos = prtd->dma_start;
 116         }
 117
 118         prtd->dma_pos = pos;
 119 }
 120
 121 static void audio_buffdone(void *data)
 122 {
 123         struct snd_pcm_substream *substream = data;
 124         struct runtime_data *prtd = substream->runtime->private_data;
 125
 126         pr_debug("Entered %s\n", __func__);
 127
 128         if (prtd->state & ST_RUNNING) {
 129                 prtd->dma_pos += prtd->dma_period;
 130                 if (prtd->dma_pos >= prtd->dma_end)
 131                         prtd->dma_pos = prtd->dma_start;
 132
 133                 if (substream)
 134                         snd_pcm_period_elapsed(substream);
 135
 136                 spin_lock(&prtd->lock);
 137                 if (!samsung_dma_has_circular()) {
 138                         prtd->dma_loaded--;
 139                         dma_enqueue(substream);
 140                 }
 141                 spin_unlock(&prtd->lock);
 142         }
 143 }
 144
 145 static int dma_hw_params(struct snd_pcm_substream *substream,
 146         struct snd_pcm_hw_params *params)
 147 {
 148         struct snd_pcm_runtime *runtime = substream->runtime;
 149         struct runtime_data *prtd = runtime->private_data;
 150         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 151         unsigned long totbytes = params_buffer_bytes(params);
 152         struct s3c_dma_params *dma =
 153                 snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 154         struct samsung_dma_req req;
 155         struct samsung_dma_config config;
 156
 157         pr_debug("Entered %s\n", __func__);
 158
 159         /* return if this is a bufferless transfer e.g.
 160          * codec <--> BT codec or GSM modem -- lg FIXME */
 161         if (!dma)
 162                 return 0;
 163
 164         /* this may get called several times by oss emulation
 165          * with different params -HW */
 166         if (prtd->params == NULL) {
 167                 /* prepare DMA */
 168                 prtd->params = dma;
 169
 170                 pr_debug("params %p, client %p, channel %d\n", prtd->params,
 171                         prtd->params->client, prtd->params->channel);
 172
 173                 prtd->params->ops = samsung_dma_get_ops();
 174
 175                 req.cap = (samsung_dma_has_circular() ?
 176                         DMA_CYCLIC : DMA_SLAVE);
 177                 req.client = prtd->params->client;
 178                 config.direction =
 179                         (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 180                         ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM);
 181                 config.width = prtd->params->dma_size;
 182                 config.fifo = prtd->params->dma_addr;
 183                 prtd->params->ch = prtd->params->ops->request(
 184                                 prtd->params->channel, &req, rtd->cpu_dai->dev,
 185                                 prtd->params->ch_name);
 186                 if (!prtd->params->ch) {
 187                         pr_err("Failed to allocate DMA channel\n");
 188                         return -ENXIO;
 189                 }
 190                 prtd->params->ops->config(prtd->params->ch, &config);
 191         }
 192
 193         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 194
 195         runtime->dma_bytes = totbytes;
 196
 197         spin_lock_irq(&prtd->lock);
 198         prtd->dma_loaded = 0;
 199         prtd->dma_period = params_period_bytes(params);
 200         prtd->dma_start = runtime->dma_addr;
 201         prtd->dma_pos = prtd->dma_start;
 202         prtd->dma_end = prtd->dma_start + totbytes;
 203         spin_unlock_irq(&prtd->lock);
 204
 205         return 0;
 206 }
 207
 208 static int dma_hw_free(struct snd_pcm_substream *substream)
 209 {
 210         struct runtime_data *prtd = substream->runtime->private_data;
 211
 212         pr_debug("Entered %s\n", __func__);
 213
 214         snd_pcm_set_runtime_buffer(substream, NULL);
 215
 216         if (prtd->params) {
 217                 prtd->params->ops->flush(prtd->params->ch);
 218                 prtd->params->ops->release(prtd->params->ch,
 219                                         prtd->params->client);
 220                 prtd->params = NULL;
 221         }
 222
 223         return 0;
 224 }
 225
 226 static int dma_prepare(struct snd_pcm_substream *substream)
 227 {
 228         struct runtime_data *prtd = substream->runtime->private_data;
 229         int ret = 0;
 230
 231         pr_debug("Entered %s\n", __func__);
 232
 233         /* return if this is a bufferless transfer e.g.
 234          * codec <--> BT codec or GSM modem -- lg FIXME */
 235         if (!prtd->params)
 236                 return 0;
 237
 238         /* flush the DMA channel */
 239         prtd->params->ops->flush(prtd->params->ch);
 240
 241         prtd->dma_loaded = 0;
 242         prtd->dma_pos = prtd->dma_start;
 243
 244         /* enqueue dma buffers */
 245         dma_enqueue(substream);
 246
 247         return ret;
 248 }
 249
 250 static int dma_trigger(struct snd_pcm_substream *substream, int cmd)
 251 {
 252         struct runtime_data *prtd = substream->runtime->private_data;
 253         int ret = 0;
 254
 255         pr_debug("Entered %s\n", __func__);
 256
 257         spin_lock(&prtd->lock);
 258
 259         switch (cmd) {
 260         case SNDRV_PCM_TRIGGER_START:
 261                 prtd->state |= ST_RUNNING;
 262                 prtd->params->ops->trigger(prtd->params->ch);
 263                 break;
 264
 265         case SNDRV_PCM_TRIGGER_STOP:
 266                 prtd->state &= ~ST_RUNNING;
 267                 prtd->params->ops->stop(prtd->params->ch);
 268                 break;
 269
 270         default:
 271                 ret = -EINVAL;
 272                 break;
 273         }
 274
 275         spin_unlock(&prtd->lock);
 276
 277         return ret;
 278 }
 279
 280 static snd_pcm_uframes_t
 281 dma_pointer(struct snd_pcm_substream *substream)
 282 {
 283         struct snd_pcm_runtime *runtime = substream->runtime;
 284         struct runtime_data *prtd = runtime->private_data;
 285         unsigned long res;
 286
 287         pr_debug("Entered %s\n", __func__);
 288
 289         res = prtd->dma_pos - prtd->dma_start;
 290
 291         pr_debug("Pointer offset: %lu\n", res);
 292
 293         /* we seem to be getting the odd error from the pcm library due
 294          * to out-of-bounds pointers. this is maybe due to the dma engine
 295          * not having loaded the new values for the channel before being
 296          * called... (todo - fix )
 297          */
 298
 299         if (res >= snd_pcm_lib_buffer_bytes(substream)) {
 300                 if (res == snd_pcm_lib_buffer_bytes(substream))
 301                         res = 0;
 302         }
 303
 304         return bytes_to_frames(substream->runtime, res);
 305 }
 306
 307 static int dma_open(struct snd_pcm_substream *substream)
 308 {
 309         struct snd_pcm_runtime *runtime = substream->runtime;
 310         struct runtime_data *prtd;
 311
 312         pr_debug("Entered %s\n", __func__);
 313
 314         snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 315         snd_soc_set_runtime_hwparams(substream, &dma_hardware);
 316
 317         prtd = kzalloc(sizeof(struct runtime_data), GFP_KERNEL);
 318         if (prtd == NULL)
 319                 return -ENOMEM;
 320
 321         spin_lock_init(&prtd->lock);
 322
 323         runtime->private_data = prtd;
 324         return 0;
 325 }
 326
 327 static int dma_close(struct snd_pcm_substream *substream)
 328 {
 329         struct snd_pcm_runtime *runtime = substream->runtime;
 330         struct runtime_data *prtd = runtime->private_data;
 331
 332         pr_debug("Entered %s\n", __func__);
 333
 334         if (!prtd)
 335                 pr_debug("dma_close called with prtd == NULL\n");
 336
 337         kfree(prtd);
 338
 339         return 0;
 340 }
 341
 342 static int dma_mmap(struct snd_pcm_substream *substream,
 343         struct vm_area_struct *vma)
 344 {
 345         struct snd_pcm_runtime *runtime = substream->runtime;
 346
 347         pr_debug("Entered %s\n", __func__);
 348
 349         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 350                                      runtime->dma_area,
 351                                      runtime->dma_addr,
 352                                      runtime->dma_bytes);
 353 }
 354
 355 static struct snd_pcm_ops dma_ops = {
 356         .open           = dma_open,
 357         .close          = dma_close,
 358         .ioctl          = snd_pcm_lib_ioctl,
 359         .hw_params      = dma_hw_params,
 360         .hw_free        = dma_hw_free,
 361         .prepare        = dma_prepare,
 362         .trigger        = dma_trigger,
 363         .pointer        = dma_pointer,
 364         .mmap           = dma_mmap,
 365 };
 366
 367 static int preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 368 {
 369         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 370         struct snd_dma_buffer *buf = &substream->dma_buffer;
 371         size_t size = dma_hardware.buffer_bytes_max;
 372
 373         pr_debug("Entered %s\n", __func__);
 374
 375         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 376         buf->dev.dev = pcm->card->dev;
 377         buf->private_data = NULL;
 378         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 379                                            &buf->addr, GFP_KERNEL);
 380         if (!buf->area)
 381                 return -ENOMEM;
 382         buf->bytes = size;
 383         return 0;
 384 }
 385
 386 static void dma_free_dma_buffers(struct snd_pcm *pcm)
 387 {
 388         struct snd_pcm_substream *substream;
 389         struct snd_dma_buffer *buf;
 390         int stream;
 391
 392         pr_debug("Entered %s\n", __func__);
 393
 394         for (stream = 0; stream < 2; stream++) {
 395                 substream = pcm->streams[stream].substream;
 396                 if (!substream)
 397                         continue;
 398
 399                 buf = &substream->dma_buffer;
 400                 if (!buf->area)
 401                         continue;
 402
 403                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 404                                       buf->area, buf->addr);
 405                 buf->area = NULL;
 406         }
 407 }
 408
 409 static int dma_new(struct snd_soc_pcm_runtime *rtd)
 410 {
 411         struct snd_card *card = rtd->card->snd_card;
 412         struct snd_pcm *pcm = rtd->pcm;
 413         int ret;
 414
 415         pr_debug("Entered %s\n", __func__);
 416
 417         ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
 418         if (ret)
 419                 return ret;
 420
 421         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 422                 ret = preallocate_dma_buffer(pcm,
 423                         SNDRV_PCM_STREAM_PLAYBACK);
 424                 if (ret)
 425                         goto out;
 426         }
 427
 428         if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
 429                 ret = preallocate_dma_buffer(pcm,
 430                         SNDRV_PCM_STREAM_CAPTURE);
 431                 if (ret)
 432                         goto out;
 433         }
 434 out:
 435         return ret;
 436 }
 437
 438 static struct snd_soc_platform_driver samsung_asoc_platform = {
 439         .ops            = &dma_ops,
 440         .pcm_new        = dma_new,
 441         .pcm_free       = dma_free_dma_buffers,
 442 };
 443
 444 int samsung_asoc_dma_platform_register(struct device *dev)
 445 {
 446         return snd_soc_register_platform(dev, &samsung_asoc_platform);
 447 }
 448 EXPORT_SYMBOL_GPL(samsung_asoc_dma_platform_register);
 449
 450 void samsung_asoc_dma_platform_unregister(struct device *dev)
 451 {
 452         snd_soc_unregister_platform(dev);
 453 }
 454 EXPORT_SYMBOL_GPL(samsung_asoc_dma_platform_unregister);
 455
 456 MODULE_AUTHOR("Ben Dooks, <ben@simtec.co.uk>");
 457 MODULE_DESCRIPTION("Samsung ASoC DMA Driver");
 458 MODULE_LICENSE("GPL");