sound/soc/sh/siu_pcm.c

   1 /*
   2  * siu_pcm.c - ALSA driver for Renesas SH7343, SH7722 SIU peripheral.
   3  *
   4  * Copyright (C) 2009-2010 Guennadi Liakhovetski <g.liakhovetski@gmx.de>
   5  * Copyright (C) 2006 Carlos Munoz <carlos@kenati.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21 #include <linux/delay.h>
  22 #include <linux/dma-mapping.h>
  23 #include <linux/dmaengine.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/module.h>
  26 #include <linux/platform_device.h>
  27
  28 #include <sound/control.h>
  29 #include <sound/core.h>
  30 #include <sound/pcm.h>
  31 #include <sound/pcm_params.h>
  32 #include <sound/soc.h>
  33
  34 #include <asm/siu.h>
  35
  36 #include "siu.h"
  37
  38 #define GET_MAX_PERIODS(buf_bytes, period_bytes) \
  39                                 ((buf_bytes) / (period_bytes))
  40 #define PERIOD_OFFSET(buf_addr, period_num, period_bytes) \
  41                                 ((buf_addr) + ((period_num) * (period_bytes)))
  42
  43 #define RWF_STM_RD              0x01            /* Read in progress */
  44 #define RWF_STM_WT              0x02            /* Write in progress */
  45
  46 struct siu_port *siu_ports[SIU_PORT_NUM];
  47
  48 /* transfersize is number of u32 dma transfers per period */
  49 static int siu_pcm_stmwrite_stop(struct siu_port *port_info)
  50 {
  51         struct siu_info *info = siu_i2s_data;
  52         u32 __iomem *base = info->reg;
  53         struct siu_stream *siu_stream = &port_info->playback;
  54         u32 stfifo;
  55
  56         if (!siu_stream->rw_flg)
  57                 return -EPERM;
  58
  59         /* output FIFO disable */
  60         stfifo = siu_read32(base + SIU_STFIFO);
  61         siu_write32(base + SIU_STFIFO, stfifo & ~0x0c180c18);
  62         pr_debug("%s: STFIFO %x -> %x\n", __func__,
  63                  stfifo, stfifo & ~0x0c180c18);
  64
  65         /* during stmwrite clear */
  66         siu_stream->rw_flg = 0;
  67
  68         return 0;
  69 }
  70
  71 static int siu_pcm_stmwrite_start(struct siu_port *port_info)
  72 {
  73         struct siu_stream *siu_stream = &port_info->playback;
  74
  75         if (siu_stream->rw_flg)
  76                 return -EPERM;
  77
  78         /* Current period in buffer */
  79         port_info->playback.cur_period = 0;
  80
  81         /* during stmwrite flag set */
  82         siu_stream->rw_flg = RWF_STM_WT;
  83
  84         /* DMA transfer start */
  85         tasklet_schedule(&siu_stream->tasklet);
  86
  87         return 0;
  88 }
  89
  90 static void siu_dma_tx_complete(void *arg)
  91 {
  92         struct siu_stream *siu_stream = arg;
  93
  94         if (!siu_stream->rw_flg)
  95                 return;
  96
  97         /* Update completed period count */
  98         if (++siu_stream->cur_period >=
  99             GET_MAX_PERIODS(siu_stream->buf_bytes,
 100                             siu_stream->period_bytes))
 101                 siu_stream->cur_period = 0;
 102
 103         pr_debug("%s: done period #%d (%u/%u bytes), cookie %d\n",
 104                 __func__, siu_stream->cur_period,
 105                 siu_stream->cur_period * siu_stream->period_bytes,
 106                 siu_stream->buf_bytes, siu_stream->cookie);
 107
 108         tasklet_schedule(&siu_stream->tasklet);
 109
 110         /* Notify alsa: a period is done */
 111         snd_pcm_period_elapsed(siu_stream->substream);
 112 }
 113
 114 static int siu_pcm_wr_set(struct siu_port *port_info,
 115                           dma_addr_t buff, u32 size)
 116 {
 117         struct siu_info *info = siu_i2s_data;
 118         u32 __iomem *base = info->reg;
 119         struct siu_stream *siu_stream = &port_info->playback;
 120         struct snd_pcm_substream *substream = siu_stream->substream;
 121         struct device *dev = substream->pcm->card->dev;
 122         struct dma_async_tx_descriptor *desc;
 123         dma_cookie_t cookie;
 124         struct scatterlist sg;
 125         u32 stfifo;
 126
 127         sg_init_table(&sg, 1);
 128         sg_set_page(&sg, pfn_to_page(PFN_DOWN(buff)),
 129                     size, offset_in_page(buff));
 130         sg_dma_len(&sg) = size;
 131         sg_dma_address(&sg) = buff;
 132
 133         desc = siu_stream->chan->device->device_prep_slave_sg(siu_stream->chan,
 134                 &sg, 1, DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 135         if (!desc) {
 136                 dev_err(dev, "Failed to allocate a dma descriptor\n");
 137                 return -ENOMEM;
 138         }
 139
 140         desc->callback = siu_dma_tx_complete;
 141         desc->callback_param = siu_stream;
 142         cookie = desc->tx_submit(desc);
 143         if (cookie < 0) {
 144                 dev_err(dev, "Failed to submit a dma transfer\n");
 145                 return cookie;
 146         }
 147
 148         siu_stream->tx_desc = desc;
 149         siu_stream->cookie = cookie;
 150
 151         dma_async_issue_pending(siu_stream->chan);
 152
 153         /* only output FIFO enable */
 154         stfifo = siu_read32(base + SIU_STFIFO);
 155         siu_write32(base + SIU_STFIFO, stfifo | (port_info->stfifo & 0x0c180c18));
 156         dev_dbg(dev, "%s: STFIFO %x -> %x\n", __func__,
 157                 stfifo, stfifo | (port_info->stfifo & 0x0c180c18));
 158
 159         return 0;
 160 }
 161
 162 static int siu_pcm_rd_set(struct siu_port *port_info,
 163                           dma_addr_t buff, size_t size)
 164 {
 165         struct siu_info *info = siu_i2s_data;
 166         u32 __iomem *base = info->reg;
 167         struct siu_stream *siu_stream = &port_info->capture;
 168         struct snd_pcm_substream *substream = siu_stream->substream;
 169         struct device *dev = substream->pcm->card->dev;
 170         struct dma_async_tx_descriptor *desc;
 171         dma_cookie_t cookie;
 172         struct scatterlist sg;
 173         u32 stfifo;
 174
 175         dev_dbg(dev, "%s: %u@%llx\n", __func__, size, (unsigned long long)buff);
 176
 177         sg_init_table(&sg, 1);
 178         sg_set_page(&sg, pfn_to_page(PFN_DOWN(buff)),
 179                     size, offset_in_page(buff));
 180         sg_dma_len(&sg) = size;
 181         sg_dma_address(&sg) = buff;
 182
 183         desc = siu_stream->chan->device->device_prep_slave_sg(siu_stream->chan,
 184                 &sg, 1, DMA_FROM_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 185         if (!desc) {
 186                 dev_err(dev, "Failed to allocate dma descriptor\n");
 187                 return -ENOMEM;
 188         }
 189
 190         desc->callback = siu_dma_tx_complete;
 191         desc->callback_param = siu_stream;
 192         cookie = desc->tx_submit(desc);
 193         if (cookie < 0) {
 194                 dev_err(dev, "Failed to submit dma descriptor\n");
 195                 return cookie;
 196         }
 197
 198         siu_stream->tx_desc = desc;
 199         siu_stream->cookie = cookie;
 200
 201         dma_async_issue_pending(siu_stream->chan);
 202
 203         /* only input FIFO enable */
 204         stfifo = siu_read32(base + SIU_STFIFO);
 205         siu_write32(base + SIU_STFIFO, siu_read32(base + SIU_STFIFO) |
 206                     (port_info->stfifo & 0x13071307));
 207         dev_dbg(dev, "%s: STFIFO %x -> %x\n", __func__,
 208                 stfifo, stfifo | (port_info->stfifo & 0x13071307));
 209
 210         return 0;
 211 }
 212
 213 static void siu_io_tasklet(unsigned long data)
 214 {
 215         struct siu_stream *siu_stream = (struct siu_stream *)data;
 216         struct snd_pcm_substream *substream = siu_stream->substream;
 217         struct device *dev = substream->pcm->card->dev;
 218         struct snd_pcm_runtime *rt = substream->runtime;
 219         struct siu_port *port_info = siu_port_info(substream);
 220
 221         dev_dbg(dev, "%s: flags %x\n", __func__, siu_stream->rw_flg);
 222
 223         if (!siu_stream->rw_flg) {
 224                 dev_dbg(dev, "%s: stream inactive\n", __func__);
 225                 return;
 226         }
 227
 228         if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
 229                 dma_addr_t buff;
 230                 size_t count;
 231                 u8 *virt;
 232
 233                 buff = (dma_addr_t)PERIOD_OFFSET(rt->dma_addr,
 234                                                 siu_stream->cur_period,
 235                                                 siu_stream->period_bytes);
 236                 virt = PERIOD_OFFSET(rt->dma_area,
 237                                      siu_stream->cur_period,
 238                                      siu_stream->period_bytes);
 239                 count = siu_stream->period_bytes;
 240
 241                 /* DMA transfer start */
 242                 siu_pcm_rd_set(port_info, buff, count);
 243         } else {
 244                 siu_pcm_wr_set(port_info,
 245                                (dma_addr_t)PERIOD_OFFSET(rt->dma_addr,
 246                                                 siu_stream->cur_period,
 247                                                 siu_stream->period_bytes),
 248                                siu_stream->period_bytes);
 249         }
 250 }
 251
 252 /* Capture */
 253 static int siu_pcm_stmread_start(struct siu_port *port_info)
 254 {
 255         struct siu_stream *siu_stream = &port_info->capture;
 256
 257         if (siu_stream->xfer_cnt > 0x1000000)
 258                 return -EINVAL;
 259         if (siu_stream->rw_flg)
 260                 return -EPERM;
 261
 262         /* Current period in buffer */
 263         siu_stream->cur_period = 0;
 264
 265         /* during stmread flag set */
 266         siu_stream->rw_flg = RWF_STM_RD;
 267
 268         tasklet_schedule(&siu_stream->tasklet);
 269
 270         return 0;
 271 }
 272
 273 static int siu_pcm_stmread_stop(struct siu_port *port_info)
 274 {
 275         struct siu_info *info = siu_i2s_data;
 276         u32 __iomem *base = info->reg;
 277         struct siu_stream *siu_stream = &port_info->capture;
 278         struct device *dev = siu_stream->substream->pcm->card->dev;
 279         u32 stfifo;
 280
 281         if (!siu_stream->rw_flg)
 282                 return -EPERM;
 283
 284         /* input FIFO disable */
 285         stfifo = siu_read32(base + SIU_STFIFO);
 286         siu_write32(base + SIU_STFIFO, stfifo & ~0x13071307);
 287         dev_dbg(dev, "%s: STFIFO %x -> %x\n", __func__,
 288                 stfifo, stfifo & ~0x13071307);
 289
 290         /* during stmread flag clear */
 291         siu_stream->rw_flg = 0;
 292
 293         return 0;
 294 }
 295
 296 static int siu_pcm_hw_params(struct snd_pcm_substream *ss,
 297                              struct snd_pcm_hw_params *hw_params)
 298 {
 299         struct siu_info *info = siu_i2s_data;
 300         struct device *dev = ss->pcm->card->dev;
 301         int ret;
 302
 303         dev_dbg(dev, "%s: port=%d\n", __func__, info->port_id);
 304
 305         ret = snd_pcm_lib_malloc_pages(ss, params_buffer_bytes(hw_params));
 306         if (ret < 0)
 307                 dev_err(dev, "snd_pcm_lib_malloc_pages() failed\n");
 308
 309         return ret;
 310 }
 311
 312 static int siu_pcm_hw_free(struct snd_pcm_substream *ss)
 313 {
 314         struct siu_info *info = siu_i2s_data;
 315         struct siu_port *port_info = siu_port_info(ss);
 316         struct device *dev = ss->pcm->card->dev;
 317         struct siu_stream *siu_stream;
 318
 319         if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
 320                 siu_stream = &port_info->playback;
 321         else
 322                 siu_stream = &port_info->capture;
 323
 324         dev_dbg(dev, "%s: port=%d\n", __func__, info->port_id);
 325
 326         return snd_pcm_lib_free_pages(ss);
 327 }
 328
 329 static bool filter(struct dma_chan *chan, void *slave)
 330 {
 331         struct sh_dmae_slave *param = slave;
 332
 333         pr_debug("%s: slave ID %d\n", __func__, param->slave_id);
 334
 335         if (unlikely(param->dma_dev != chan->device->dev))
 336                 return false;
 337
 338         chan->private = param;
 339         return true;
 340 }
 341
 342 static int siu_pcm_open(struct snd_pcm_substream *ss)
 343 {
 344         /* Playback / Capture */
 345         struct snd_soc_pcm_runtime *rtd = ss->private_data;
 346         struct siu_platform *pdata = rtd->platform->dev->platform_data;
 347         struct siu_info *info = siu_i2s_data;
 348         struct siu_port *port_info = siu_port_info(ss);
 349         struct siu_stream *siu_stream;
 350         u32 port = info->port_id;
 351         struct device *dev = ss->pcm->card->dev;
 352         dma_cap_mask_t mask;
 353         struct sh_dmae_slave *param;
 354
 355         dma_cap_zero(mask);
 356         dma_cap_set(DMA_SLAVE, mask);
 357
 358         dev_dbg(dev, "%s, port=%d@%p\n", __func__, port, port_info);
 359
 360         if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 361                 siu_stream = &port_info->playback;
 362                 param = &siu_stream->param;
 363                 param->slave_id = port ? pdata->dma_slave_tx_b :
 364                         pdata->dma_slave_tx_a;
 365         } else {
 366                 siu_stream = &port_info->capture;
 367                 param = &siu_stream->param;
 368                 param->slave_id = port ? pdata->dma_slave_rx_b :
 369                         pdata->dma_slave_rx_a;
 370         }
 371
 372         param->dma_dev = pdata->dma_dev;
 373         /* Get DMA channel */
 374         siu_stream->chan = dma_request_channel(mask, filter, param);
 375         if (!siu_stream->chan) {
 376                 dev_err(dev, "DMA channel allocation failed!\n");
 377                 return -EBUSY;
 378         }
 379
 380         siu_stream->substream = ss;
 381
 382         return 0;
 383 }
 384
 385 static int siu_pcm_close(struct snd_pcm_substream *ss)
 386 {
 387         struct siu_info *info = siu_i2s_data;
 388         struct device *dev = ss->pcm->card->dev;
 389         struct siu_port *port_info = siu_port_info(ss);
 390         struct siu_stream *siu_stream;
 391
 392         dev_dbg(dev, "%s: port=%d\n", __func__, info->port_id);
 393
 394         if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
 395                 siu_stream = &port_info->playback;
 396         else
 397                 siu_stream = &port_info->capture;
 398
 399         dma_release_channel(siu_stream->chan);
 400         siu_stream->chan = NULL;
 401
 402         siu_stream->substream = NULL;
 403
 404         return 0;
 405 }
 406
 407 static int siu_pcm_prepare(struct snd_pcm_substream *ss)
 408 {
 409         struct siu_info *info = siu_i2s_data;
 410         struct siu_port *port_info = siu_port_info(ss);
 411         struct device *dev = ss->pcm->card->dev;
 412         struct snd_pcm_runtime  *rt = ss->runtime;
 413         struct siu_stream *siu_stream;
 414         snd_pcm_sframes_t xfer_cnt;
 415
 416         if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
 417                 siu_stream = &port_info->playback;
 418         else
 419                 siu_stream = &port_info->capture;
 420
 421         rt = siu_stream->substream->runtime;
 422
 423         siu_stream->buf_bytes = snd_pcm_lib_buffer_bytes(ss);
 424         siu_stream->period_bytes = snd_pcm_lib_period_bytes(ss);
 425
 426         dev_dbg(dev, "%s: port=%d, %d channels, period=%u bytes\n", __func__,
 427                 info->port_id, rt->channels, siu_stream->period_bytes);
 428
 429         /* We only support buffers that are multiples of the period */
 430         if (siu_stream->buf_bytes % siu_stream->period_bytes) {
 431                 dev_err(dev, "%s() - buffer=%d not multiple of period=%d\n",
 432                        __func__, siu_stream->buf_bytes,
 433                        siu_stream->period_bytes);
 434                 return -EINVAL;
 435         }
 436
 437         xfer_cnt = bytes_to_frames(rt, siu_stream->period_bytes);
 438         if (!xfer_cnt || xfer_cnt > 0x1000000)
 439                 return -EINVAL;
 440
 441         siu_stream->format = rt->format;
 442         siu_stream->xfer_cnt = xfer_cnt;
 443
 444         dev_dbg(dev, "port=%d buf=%lx buf_bytes=%d period_bytes=%d "
 445                 "format=%d channels=%d xfer_cnt=%d\n", info->port_id,
 446                 (unsigned long)rt->dma_addr, siu_stream->buf_bytes,
 447                 siu_stream->period_bytes,
 448                 siu_stream->format, rt->channels, (int)xfer_cnt);
 449
 450         return 0;
 451 }
 452
 453 static int siu_pcm_trigger(struct snd_pcm_substream *ss, int cmd)
 454 {
 455         struct siu_info *info = siu_i2s_data;
 456         struct device *dev = ss->pcm->card->dev;
 457         struct siu_port *port_info = siu_port_info(ss);
 458         int ret;
 459
 460         dev_dbg(dev, "%s: port=%d@%p, cmd=%d\n", __func__,
 461                 info->port_id, port_info, cmd);
 462
 463         switch (cmd) {
 464         case SNDRV_PCM_TRIGGER_START:
 465                 if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
 466                         ret = siu_pcm_stmwrite_start(port_info);
 467                 else
 468                         ret = siu_pcm_stmread_start(port_info);
 469
 470                 if (ret < 0)
 471                         dev_warn(dev, "%s: start failed on port=%d\n",
 472                                  __func__, info->port_id);
 473
 474                 break;
 475         case SNDRV_PCM_TRIGGER_STOP:
 476                 if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
 477                         siu_pcm_stmwrite_stop(port_info);
 478                 else
 479                         siu_pcm_stmread_stop(port_info);
 480                 ret = 0;
 481
 482                 break;
 483         default:
 484                 dev_err(dev, "%s() unsupported cmd=%d\n", __func__, cmd);
 485                 ret = -EINVAL;
 486         }
 487
 488         return ret;
 489 }
 490
 491 /*
 492  * So far only resolution of one period is supported, subject to extending the
 493  * dmangine API
 494  */
 495 static snd_pcm_uframes_t siu_pcm_pointer_dma(struct snd_pcm_substream *ss)
 496 {
 497         struct device *dev = ss->pcm->card->dev;
 498         struct siu_info *info = siu_i2s_data;
 499         u32 __iomem *base = info->reg;
 500         struct siu_port *port_info = siu_port_info(ss);
 501         struct snd_pcm_runtime *rt = ss->runtime;
 502         size_t ptr;
 503         struct siu_stream *siu_stream;
 504
 505         if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
 506                 siu_stream = &port_info->playback;
 507         else
 508                 siu_stream = &port_info->capture;
 509
 510         /*
 511          * ptr is the offset into the buffer where the dma is currently at. We
 512          * check if the dma buffer has just wrapped.
 513          */
 514         ptr = PERIOD_OFFSET(rt->dma_addr,
 515                             siu_stream->cur_period,
 516                             siu_stream->period_bytes) - rt->dma_addr;
 517
 518         dev_dbg(dev,
 519                 "%s: port=%d, events %x, FSTS %x, xferred %u/%u, cookie %d\n",
 520                 __func__, info->port_id, siu_read32(base + SIU_EVNTC),
 521                 siu_read32(base + SIU_SBFSTS), ptr, siu_stream->buf_bytes,
 522                 siu_stream->cookie);
 523
 524         if (ptr >= siu_stream->buf_bytes)
 525                 ptr = 0;
 526
 527         return bytes_to_frames(ss->runtime, ptr);
 528 }
 529
 530 static int siu_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
 531                        struct snd_pcm *pcm)
 532 {
 533         /* card->dev == socdev->dev, see snd_soc_new_pcms() */
 534         struct siu_info *info = siu_i2s_data;
 535         struct platform_device *pdev = to_platform_device(card->dev);
 536         int ret;
 537         int i;
 538
 539         /* pdev->id selects between SIUA and SIUB */
 540         if (pdev->id < 0 || pdev->id >= SIU_PORT_NUM)
 541                 return -EINVAL;
 542
 543         info->port_id = pdev->id;
 544
 545         /*
 546          * While the siu has 2 ports, only one port can be on at a time (only 1
 547          * SPB). So far all the boards using the siu had only one of the ports
 548          * wired to a codec. To simplify things, we only register one port with
 549          * alsa. In case both ports are needed, it should be changed here
 550          */
 551         for (i = pdev->id; i < pdev->id + 1; i++) {
 552                 struct siu_port **port_info = &siu_ports[i];
 553
 554                 ret = siu_init_port(i, port_info, card);
 555                 if (ret < 0)
 556                         return ret;
 557
 558                 ret = snd_pcm_lib_preallocate_pages_for_all(pcm,
 559                                 SNDRV_DMA_TYPE_DEV, NULL,
 560                                 SIU_BUFFER_BYTES_MAX, SIU_BUFFER_BYTES_MAX);
 561                 if (ret < 0) {
 562                         dev_err(card->dev,
 563                                "snd_pcm_lib_preallocate_pages_for_all() err=%d",
 564                                 ret);
 565                         goto fail;
 566                 }
 567
 568                 (*port_info)->pcm = pcm;
 569
 570                 /* IO tasklets */
 571                 tasklet_init(&(*port_info)->playback.tasklet, siu_io_tasklet,
 572                              (unsigned long)&(*port_info)->playback);
 573                 tasklet_init(&(*port_info)->capture.tasklet, siu_io_tasklet,
 574                              (unsigned long)&(*port_info)->capture);
 575         }
 576
 577         dev_info(card->dev, "SuperH SIU driver initialized.\n");
 578         return 0;
 579
 580 fail:
 581         siu_free_port(siu_ports[pdev->id]);
 582         dev_err(card->dev, "SIU: failed to initialize.\n");
 583         return ret;
 584 }
 585
 586 static void siu_pcm_free(struct snd_pcm *pcm)
 587 {
 588         struct platform_device *pdev = to_platform_device(pcm->card->dev);
 589         struct siu_port *port_info = siu_ports[pdev->id];
 590
 591         tasklet_kill(&port_info->capture.tasklet);
 592         tasklet_kill(&port_info->playback.tasklet);
 593
 594         siu_free_port(port_info);
 595         snd_pcm_lib_preallocate_free_for_all(pcm);
 596
 597         dev_dbg(pcm->card->dev, "%s\n", __func__);
 598 }
 599
 600 static struct snd_pcm_ops siu_pcm_ops = {
 601         .open           = siu_pcm_open,
 602         .close          = siu_pcm_close,
 603         .ioctl          = snd_pcm_lib_ioctl,
 604         .hw_params      = siu_pcm_hw_params,
 605         .hw_free        = siu_pcm_hw_free,
 606         .prepare        = siu_pcm_prepare,
 607         .trigger        = siu_pcm_trigger,
 608         .pointer        = siu_pcm_pointer_dma,
 609 };
 610
 611 struct snd_soc_platform_driver siu_platform = {
 612         .ops                    = &siu_pcm_ops,
 613         .pcm_new        = siu_pcm_new,
 614         .pcm_free       = siu_pcm_free,
 615 };
 616 EXPORT_SYMBOL_GPL(siu_platform);