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 #include <linux/slab.h>
  28
  29 #include <sound/control.h>
  30 #include <sound/core.h>
  31 #include <sound/pcm.h>
  32 #include <sound/pcm_params.h>
  33 #include <sound/soc-dai.h>
  34
  35 #include <asm/dma-sh.h>
  36 #include <asm/siu.h>
  37
  38 #include "siu.h"
  39
  40 #define GET_MAX_PERIODS(buf_bytes, period_bytes) \
  41                                 ((buf_bytes) / (period_bytes))
  42 #define PERIOD_OFFSET(buf_addr, period_num, period_bytes) \
  43                                 ((buf_addr) + ((period_num) * (period_bytes)))
  44
  45 #define RWF_STM_RD              0x01            /* Read in progress */
  46 #define RWF_STM_WT              0x02            /* Write in progress */
  47
  48 struct siu_port *siu_ports[SIU_PORT_NUM];
  49
  50 /* transfersize is number of u32 dma transfers per period */
  51 static int siu_pcm_stmwrite_stop(struct siu_port *port_info)
  52 {
  53         struct siu_info *info = siu_i2s_dai.private_data;
  54         u32 __iomem *base = info->reg;
  55         struct siu_stream *siu_stream = &port_info->playback;
  56         u32 stfifo;
  57
  58         if (!siu_stream->rw_flg)
  59                 return -EPERM;
  60
  61         /* output FIFO disable */
  62         stfifo = siu_read32(base + SIU_STFIFO);
  63         siu_write32(base + SIU_STFIFO, stfifo & ~0x0c180c18);
  64         pr_debug("%s: STFIFO %x -> %x\n", __func__,
  65                  stfifo, stfifo & ~0x0c180c18);
  66
  67         /* during stmwrite clear */
  68         siu_stream->rw_flg = 0;
  69
  70         return 0;
  71 }
  72
  73 static int siu_pcm_stmwrite_start(struct siu_port *port_info)
  74 {
  75         struct siu_stream *siu_stream = &port_info->playback;
  76
  77         if (siu_stream->rw_flg)
  78                 return -EPERM;
  79
  80         /* Current period in buffer */
  81         port_info->playback.cur_period = 0;
  82
  83         /* during stmwrite flag set */
  84         siu_stream->rw_flg = RWF_STM_WT;
  85
  86         /* DMA transfer start */
  87         tasklet_schedule(&siu_stream->tasklet);
  88
  89         return 0;
  90 }
  91
  92 static void siu_dma_tx_complete(void *arg)
  93 {
  94         struct siu_stream *siu_stream = arg;
  95
  96         if (!siu_stream->rw_flg)
  97                 return;
  98
  99         /* Update completed period count */
 100         if (++siu_stream->cur_period >=
 101             GET_MAX_PERIODS(siu_stream->buf_bytes,
 102                             siu_stream->period_bytes))
 103                 siu_stream->cur_period = 0;
 104
 105         pr_debug("%s: done period #%d (%u/%u bytes), cookie %d\n",
 106                 __func__, siu_stream->cur_period,
 107                 siu_stream->cur_period * siu_stream->period_bytes,
 108                 siu_stream->buf_bytes, siu_stream->cookie);
 109
 110         tasklet_schedule(&siu_stream->tasklet);
 111
 112         /* Notify alsa: a period is done */
 113         snd_pcm_period_elapsed(siu_stream->substream);
 114 }
 115
 116 static int siu_pcm_wr_set(struct siu_port *port_info,
 117                           dma_addr_t buff, u32 size)
 118 {
 119         struct siu_info *info = siu_i2s_dai.private_data;
 120         u32 __iomem *base = info->reg;
 121         struct siu_stream *siu_stream = &port_info->playback;
 122         struct snd_pcm_substream *substream = siu_stream->substream;
 123         struct device *dev = substream->pcm->card->dev;
 124         struct dma_async_tx_descriptor *desc;
 125         dma_cookie_t cookie;
 126         struct scatterlist sg;
 127         u32 stfifo;
 128
 129         sg_init_table(&sg, 1);
 130         sg_set_page(&sg, pfn_to_page(PFN_DOWN(buff)),
 131                     size, offset_in_page(buff));
 132         sg_dma_address(&sg) = buff;
 133
 134         desc = siu_stream->chan->device->device_prep_slave_sg(siu_stream->chan,
 135                 &sg, 1, DMA_TO_DEVICE, DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
 136         if (!desc) {
 137                 dev_err(dev, "Failed to allocate a dma descriptor\n");
 138                 return -ENOMEM;
 139         }
 140
 141         desc->callback = siu_dma_tx_complete;
 142         desc->callback_param = siu_stream;
 143         cookie = desc->tx_submit(desc);
 144         if (cookie < 0) {
 145                 dev_err(dev, "Failed to submit a dma transfer\n");
 146                 return cookie;
 147         }
 148
 149         siu_stream->tx_desc = desc;
 150         siu_stream->cookie = cookie;
 151
 152         dma_async_issue_pending(siu_stream->chan);
 153
 154         /* only output FIFO enable */
 155         stfifo = siu_read32(base + SIU_STFIFO);
 156         siu_write32(base + SIU_STFIFO, stfifo | (port_info->stfifo & 0x0c180c18));
 157         dev_dbg(dev, "%s: STFIFO %x -> %x\n", __func__,
 158                 stfifo, stfifo | (port_info->stfifo & 0x0c180c18));
 159
 160         return 0;
 161 }
 162
 163 static int siu_pcm_rd_set(struct siu_port *port_info,
 164                           dma_addr_t buff, size_t size)
 165 {
 166         struct siu_info *info = siu_i2s_dai.private_data;
 167         u32 __iomem *base = info->reg;
 168         struct siu_stream *siu_stream = &port_info->capture;
 169         struct snd_pcm_substream *substream = siu_stream->substream;
 170         struct device *dev = substream->pcm->card->dev;
 171         struct dma_async_tx_descriptor *desc;
 172         dma_cookie_t cookie;
 173         struct scatterlist sg;
 174         u32 stfifo;
 175
 176         dev_dbg(dev, "%s: %u@%llx\n", __func__, size, (unsigned long long)buff);
 177
 178         sg_init_table(&sg, 1);
 179         sg_set_page(&sg, pfn_to_page(PFN_DOWN(buff)),
 180                     size, offset_in_page(buff));
 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_dai.private_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_dai.private_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_dai.private_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 siu_info *info = siu_i2s_dai.private_data;
 346         struct siu_port *port_info = siu_port_info(ss);
 347         struct siu_stream *siu_stream;
 348         u32 port = info->port_id;
 349         struct siu_platform *pdata = siu_i2s_dai.dev->platform_data;
 350         struct device *dev = ss->pcm->card->dev;
 351         dma_cap_mask_t mask;
 352         struct sh_dmae_slave *param;
 353
 354         dma_cap_zero(mask);
 355         dma_cap_set(DMA_SLAVE, mask);
 356
 357         dev_dbg(dev, "%s, port=%d@%p\n", __func__, port, port_info);
 358
 359         if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 360                 siu_stream = &port_info->playback;
 361                 param = &siu_stream->param;
 362                 param->slave_id = port ? SHDMA_SLAVE_SIUB_TX :
 363                         SHDMA_SLAVE_SIUA_TX;
 364         } else {
 365                 siu_stream = &port_info->capture;
 366                 param = &siu_stream->param;
 367                 param->slave_id = port ? SHDMA_SLAVE_SIUB_RX :
 368                         SHDMA_SLAVE_SIUA_RX;
 369         }
 370
 371         param->dma_dev = pdata->dma_dev;
 372         /* Get DMA channel */
 373         siu_stream->chan = dma_request_channel(mask, filter, param);
 374         if (!siu_stream->chan) {
 375                 dev_err(dev, "DMA channel allocation failed!\n");
 376                 return -EBUSY;
 377         }
 378
 379         siu_stream->substream = ss;
 380
 381         return 0;
 382 }
 383
 384 static int siu_pcm_close(struct snd_pcm_substream *ss)
 385 {
 386         struct siu_info *info = siu_i2s_dai.private_data;
 387         struct device *dev = ss->pcm->card->dev;
 388         struct siu_port *port_info = siu_port_info(ss);
 389         struct siu_stream *siu_stream;
 390
 391         dev_dbg(dev, "%s: port=%d\n", __func__, info->port_id);
 392
 393         if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
 394                 siu_stream = &port_info->playback;
 395         else
 396                 siu_stream = &port_info->capture;
 397
 398         dma_release_channel(siu_stream->chan);
 399         siu_stream->chan = NULL;
 400
 401         siu_stream->substream = NULL;
 402
 403         return 0;
 404 }
 405
 406 static int siu_pcm_prepare(struct snd_pcm_substream *ss)
 407 {
 408         struct siu_info *info = siu_i2s_dai.private_data;
 409         struct siu_port *port_info = siu_port_info(ss);
 410         struct device *dev = ss->pcm->card->dev;
 411         struct snd_pcm_runtime  *rt = ss->runtime;
 412         struct siu_stream *siu_stream;
 413         snd_pcm_sframes_t xfer_cnt;
 414
 415         if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
 416                 siu_stream = &port_info->playback;
 417         else
 418                 siu_stream = &port_info->capture;
 419
 420         rt = siu_stream->substream->runtime;
 421
 422         siu_stream->buf_bytes = snd_pcm_lib_buffer_bytes(ss);
 423         siu_stream->period_bytes = snd_pcm_lib_period_bytes(ss);
 424
 425         dev_dbg(dev, "%s: port=%d, %d channels, period=%u bytes\n", __func__,
 426                 info->port_id, rt->channels, siu_stream->period_bytes);
 427
 428         /* We only support buffers that are multiples of the period */
 429         if (siu_stream->buf_bytes % siu_stream->period_bytes) {
 430                 dev_err(dev, "%s() - buffer=%d not multiple of period=%d\n",
 431                        __func__, siu_stream->buf_bytes,
 432                        siu_stream->period_bytes);
 433                 return -EINVAL;
 434         }
 435
 436         xfer_cnt = bytes_to_frames(rt, siu_stream->period_bytes);
 437         if (!xfer_cnt || xfer_cnt > 0x1000000)
 438                 return -EINVAL;
 439
 440         siu_stream->format = rt->format;
 441         siu_stream->xfer_cnt = xfer_cnt;
 442
 443         dev_dbg(dev, "port=%d buf=%lx buf_bytes=%d period_bytes=%d "
 444                 "format=%d channels=%d xfer_cnt=%d\n", info->port_id,
 445                 (unsigned long)rt->dma_addr, siu_stream->buf_bytes,
 446                 siu_stream->period_bytes,
 447                 siu_stream->format, rt->channels, (int)xfer_cnt);
 448
 449         return 0;
 450 }
 451
 452 static int siu_pcm_trigger(struct snd_pcm_substream *ss, int cmd)
 453 {
 454         struct siu_info *info = siu_i2s_dai.private_data;
 455         struct device *dev = ss->pcm->card->dev;
 456         struct siu_port *port_info = siu_port_info(ss);
 457         int ret;
 458
 459         dev_dbg(dev, "%s: port=%d@%p, cmd=%d\n", __func__,
 460                 info->port_id, port_info, cmd);
 461
 462         switch (cmd) {
 463         case SNDRV_PCM_TRIGGER_START:
 464                 if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
 465                         ret = siu_pcm_stmwrite_start(port_info);
 466                 else
 467                         ret = siu_pcm_stmread_start(port_info);
 468
 469                 if (ret < 0)
 470                         dev_warn(dev, "%s: start failed on port=%d\n",
 471                                  __func__, info->port_id);
 472
 473                 break;
 474         case SNDRV_PCM_TRIGGER_STOP:
 475                 if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
 476                         siu_pcm_stmwrite_stop(port_info);
 477                 else
 478                         siu_pcm_stmread_stop(port_info);
 479                 ret = 0;
 480
 481                 break;
 482         default:
 483                 dev_err(dev, "%s() unsupported cmd=%d\n", __func__, cmd);
 484                 ret = -EINVAL;
 485         }
 486
 487         return ret;
 488 }
 489
 490 /*
 491  * So far only resolution of one period is supported, subject to extending the
 492  * dmangine API
 493  */
 494 static snd_pcm_uframes_t siu_pcm_pointer_dma(struct snd_pcm_substream *ss)
 495 {
 496         struct device *dev = ss->pcm->card->dev;
 497         struct siu_info *info = siu_i2s_dai.private_data;
 498         u32 __iomem *base = info->reg;
 499         struct siu_port *port_info = siu_port_info(ss);
 500         struct snd_pcm_runtime *rt = ss->runtime;
 501         size_t ptr;
 502         struct siu_stream *siu_stream;
 503
 504         if (ss->stream == SNDRV_PCM_STREAM_PLAYBACK)
 505                 siu_stream = &port_info->playback;
 506         else
 507                 siu_stream = &port_info->capture;
 508
 509         /*
 510          * ptr is the offset into the buffer where the dma is currently at. We
 511          * check if the dma buffer has just wrapped.
 512          */
 513         ptr = PERIOD_OFFSET(rt->dma_addr,
 514                             siu_stream->cur_period,
 515                             siu_stream->period_bytes) - rt->dma_addr;
 516
 517         dev_dbg(dev,
 518                 "%s: port=%d, events %x, FSTS %x, xferred %u/%u, cookie %d\n",
 519                 __func__, info->port_id, siu_read32(base + SIU_EVNTC),
 520                 siu_read32(base + SIU_SBFSTS), ptr, siu_stream->buf_bytes,
 521                 siu_stream->cookie);
 522
 523         if (ptr >= siu_stream->buf_bytes)
 524                 ptr = 0;
 525
 526         return bytes_to_frames(ss->runtime, ptr);
 527 }
 528
 529 static int siu_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
 530                        struct snd_pcm *pcm)
 531 {
 532         /* card->dev == socdev->dev, see snd_soc_new_pcms() */
 533         struct siu_info *info = siu_i2s_dai.private_data;
 534         struct platform_device *pdev = to_platform_device(card->dev);
 535         int ret;
 536         int i;
 537
 538         /* pdev->id selects between SIUA and SIUB */
 539         if (pdev->id < 0 || pdev->id >= SIU_PORT_NUM)
 540                 return -EINVAL;
 541
 542         info->port_id = pdev->id;
 543
 544         /*
 545          * While the siu has 2 ports, only one port can be on at a time (only 1
 546          * SPB). So far all the boards using the siu had only one of the ports
 547          * wired to a codec. To simplify things, we only register one port with
 548          * alsa. In case both ports are needed, it should be changed here
 549          */
 550         for (i = pdev->id; i < pdev->id + 1; i++) {
 551                 struct siu_port **port_info = &siu_ports[i];
 552
 553                 ret = siu_init_port(i, port_info, card);
 554                 if (ret < 0)
 555                         return ret;
 556
 557                 ret = snd_pcm_lib_preallocate_pages_for_all(pcm,
 558                                 SNDRV_DMA_TYPE_DEV, NULL,
 559                                 SIU_BUFFER_BYTES_MAX, SIU_BUFFER_BYTES_MAX);
 560                 if (ret < 0) {
 561                         dev_err(card->dev,
 562                                "snd_pcm_lib_preallocate_pages_for_all() err=%d",
 563                                 ret);
 564                         goto fail;
 565                 }
 566
 567                 (*port_info)->pcm = pcm;
 568
 569                 /* IO tasklets */
 570                 tasklet_init(&(*port_info)->playback.tasklet, siu_io_tasklet,
 571                              (unsigned long)&(*port_info)->playback);
 572                 tasklet_init(&(*port_info)->capture.tasklet, siu_io_tasklet,
 573                              (unsigned long)&(*port_info)->capture);
 574         }
 575
 576         dev_info(card->dev, "SuperH SIU driver initialized.\n");
 577         return 0;
 578
 579 fail:
 580         siu_free_port(siu_ports[pdev->id]);
 581         dev_err(card->dev, "SIU: failed to initialize.\n");
 582         return ret;
 583 }
 584
 585 static void siu_pcm_free(struct snd_pcm *pcm)
 586 {
 587         struct platform_device *pdev = to_platform_device(pcm->card->dev);
 588         struct siu_port *port_info = siu_ports[pdev->id];
 589
 590         tasklet_kill(&port_info->capture.tasklet);
 591         tasklet_kill(&port_info->playback.tasklet);
 592
 593         siu_free_port(port_info);
 594         snd_pcm_lib_preallocate_free_for_all(pcm);
 595
 596         dev_dbg(pcm->card->dev, "%s\n", __func__);
 597 }
 598
 599 static struct snd_pcm_ops siu_pcm_ops = {
 600         .open           = siu_pcm_open,
 601         .close          = siu_pcm_close,
 602         .ioctl          = snd_pcm_lib_ioctl,
 603         .hw_params      = siu_pcm_hw_params,
 604         .hw_free        = siu_pcm_hw_free,
 605         .prepare        = siu_pcm_prepare,
 606         .trigger        = siu_pcm_trigger,
 607         .pointer        = siu_pcm_pointer_dma,
 608 };
 609
 610 struct snd_soc_platform siu_platform = {
 611         .name           = "siu-audio",
 612         .pcm_ops        = &siu_pcm_ops,
 613         .pcm_new        = siu_pcm_new,
 614         .pcm_free       = siu_pcm_free,
 615 };
 616 EXPORT_SYMBOL_GPL(siu_platform);