sound/soc/omap/omap-pcm.c

   1 /*
   2  * omap-pcm.c  --  ALSA PCM interface for the OMAP SoC
   3  *
   4  * Copyright (C) 2008 Nokia Corporation
   5  *
   6  * Contact: Jarkko Nikula <jhnikula@gmail.com>
   7  *          Peter Ujfalusi <peter.ujfalusi@nokia.com>
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License
  11  * version 2 as published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  21  * 02110-1301 USA
  22  *
  23  */
  24
  25 #include <linux/dma-mapping.h>
  26 #include <sound/core.h>
  27 #include <sound/pcm.h>
  28 #include <sound/pcm_params.h>
  29 #include <sound/soc.h>
  30
  31 #include <mach/dma.h>
  32 #include "omap-pcm.h"
  33
  34 static const struct snd_pcm_hardware omap_pcm_hardware = {
  35         .info                   = SNDRV_PCM_INFO_MMAP |
  36                                   SNDRV_PCM_INFO_MMAP_VALID |
  37                                   SNDRV_PCM_INFO_INTERLEAVED |
  38                                   SNDRV_PCM_INFO_PAUSE |
  39                                   SNDRV_PCM_INFO_RESUME,
  40         .formats                = SNDRV_PCM_FMTBIT_S16_LE,
  41         .period_bytes_min       = 32,
  42         .period_bytes_max       = 64 * 1024,
  43         .periods_min            = 2,
  44         .periods_max            = 255,
  45         .buffer_bytes_max       = 128 * 1024,
  46 };
  47
  48 struct omap_runtime_data {
  49         spinlock_t                      lock;
  50         struct omap_pcm_dma_data        *dma_data;
  51         int                             dma_ch;
  52         int                             period_index;
  53 };
  54
  55 static void omap_pcm_dma_irq(int ch, u16 stat, void *data)
  56 {
  57         struct snd_pcm_substream *substream = data;
  58         struct snd_pcm_runtime *runtime = substream->runtime;
  59         struct omap_runtime_data *prtd = runtime->private_data;
  60         unsigned long flags;
  61
  62         if ((cpu_is_omap1510()) &&
  63                         (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)) {
  64                 /*
  65                  * OMAP1510 doesn't fully support DMA progress counter
  66                  * and there is no software emulation implemented yet,
  67                  * so have to maintain our own playback progress counter
  68                  * that can be used by omap_pcm_pointer() instead.
  69                  */
  70                 spin_lock_irqsave(&prtd->lock, flags);
  71                 if ((stat == OMAP_DMA_LAST_IRQ) &&
  72                                 (prtd->period_index == runtime->periods - 1)) {
  73                         /* we are in sync, do nothing */
  74                         spin_unlock_irqrestore(&prtd->lock, flags);
  75                         return;
  76                 }
  77                 if (prtd->period_index >= 0) {
  78                         if (stat & OMAP_DMA_BLOCK_IRQ) {
  79                                 /* end of buffer reached, loop back */
  80                                 prtd->period_index = 0;
  81                         } else if (stat & OMAP_DMA_LAST_IRQ) {
  82                                 /* update the counter for the last period */
  83                                 prtd->period_index = runtime->periods - 1;
  84                         } else if (++prtd->period_index >= runtime->periods) {
  85                                 /* end of buffer missed? loop back */
  86                                 prtd->period_index = 0;
  87                         }
  88                 }
  89                 spin_unlock_irqrestore(&prtd->lock, flags);
  90         }
  91
  92         snd_pcm_period_elapsed(substream);
  93 }
  94
  95 /* this may get called several times by oss emulation */
  96 static int omap_pcm_hw_params(struct snd_pcm_substream *substream,
  97                               struct snd_pcm_hw_params *params)
  98 {
  99         struct snd_pcm_runtime *runtime = substream->runtime;
 100         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 101         struct omap_runtime_data *prtd = runtime->private_data;
 102         struct omap_pcm_dma_data *dma_data = rtd->dai->cpu_dai->dma_data;
 103         int err = 0;
 104
 105         /* return if this is a bufferless transfer e.g.
 106          * codec <--> BT codec or GSM modem -- lg FIXME */
 107         if (!dma_data)
 108                 return 0;
 109
 110         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 111         runtime->dma_bytes = params_buffer_bytes(params);
 112
 113         if (prtd->dma_data)
 114                 return 0;
 115         prtd->dma_data = dma_data;
 116         err = omap_request_dma(dma_data->dma_req, dma_data->name,
 117                                omap_pcm_dma_irq, substream, &prtd->dma_ch);
 118         if (!err) {
 119                 /*
 120                  * Link channel with itself so DMA doesn't need any
 121                  * reprogramming while looping the buffer
 122                  */
 123                 omap_dma_link_lch(prtd->dma_ch, prtd->dma_ch);
 124         }
 125
 126         return err;
 127 }
 128
 129 static int omap_pcm_hw_free(struct snd_pcm_substream *substream)
 130 {
 131         struct snd_pcm_runtime *runtime = substream->runtime;
 132         struct omap_runtime_data *prtd = runtime->private_data;
 133
 134         if (prtd->dma_data == NULL)
 135                 return 0;
 136
 137         omap_dma_unlink_lch(prtd->dma_ch, prtd->dma_ch);
 138         omap_free_dma(prtd->dma_ch);
 139         prtd->dma_data = NULL;
 140
 141         snd_pcm_set_runtime_buffer(substream, NULL);
 142
 143         return 0;
 144 }
 145
 146 static int omap_pcm_prepare(struct snd_pcm_substream *substream)
 147 {
 148         struct snd_pcm_runtime *runtime = substream->runtime;
 149         struct omap_runtime_data *prtd = runtime->private_data;
 150         struct omap_pcm_dma_data *dma_data = prtd->dma_data;
 151         struct omap_dma_channel_params dma_params;
 152
 153         /* return if this is a bufferless transfer e.g.
 154          * codec <--> BT codec or GSM modem -- lg FIXME */
 155         if (!prtd->dma_data)
 156                 return 0;
 157
 158         memset(&dma_params, 0, sizeof(dma_params));
 159         /*
 160          * Note: Regardless of interface data formats supported by OMAP McBSP
 161          * or EAC blocks, internal representation is always fixed 16-bit/sample
 162          */
 163         dma_params.data_type                    = OMAP_DMA_DATA_TYPE_S16;
 164         dma_params.trigger                      = dma_data->dma_req;
 165         dma_params.sync_mode                    = OMAP_DMA_SYNC_ELEMENT;
 166         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 167                 dma_params.src_amode            = OMAP_DMA_AMODE_POST_INC;
 168                 dma_params.dst_amode            = OMAP_DMA_AMODE_CONSTANT;
 169                 dma_params.src_or_dst_synch     = OMAP_DMA_DST_SYNC;
 170                 dma_params.src_start            = runtime->dma_addr;
 171                 dma_params.dst_start            = dma_data->port_addr;
 172                 dma_params.dst_port             = OMAP_DMA_PORT_MPUI;
 173         } else {
 174                 dma_params.src_amode            = OMAP_DMA_AMODE_CONSTANT;
 175                 dma_params.dst_amode            = OMAP_DMA_AMODE_POST_INC;
 176                 dma_params.src_or_dst_synch     = OMAP_DMA_SRC_SYNC;
 177                 dma_params.src_start            = dma_data->port_addr;
 178                 dma_params.dst_start            = runtime->dma_addr;
 179                 dma_params.src_port             = OMAP_DMA_PORT_MPUI;
 180         }
 181         /*
 182          * Set DMA transfer frame size equal to ALSA period size and frame
 183          * count as no. of ALSA periods. Then with DMA frame interrupt enabled,
 184          * we can transfer the whole ALSA buffer with single DMA transfer but
 185          * still can get an interrupt at each period bounary
 186          */
 187         dma_params.elem_count   = snd_pcm_lib_period_bytes(substream) / 2;
 188         dma_params.frame_count  = runtime->periods;
 189         omap_set_dma_params(prtd->dma_ch, &dma_params);
 190
 191         if ((cpu_is_omap1510()) &&
 192                         (substream->stream == SNDRV_PCM_STREAM_PLAYBACK))
 193                 omap_enable_dma_irq(prtd->dma_ch, OMAP_DMA_FRAME_IRQ |
 194                               OMAP_DMA_LAST_IRQ | OMAP_DMA_BLOCK_IRQ);
 195         else
 196                 omap_enable_dma_irq(prtd->dma_ch, OMAP_DMA_FRAME_IRQ);
 197
 198         return 0;
 199 }
 200
 201 static int omap_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 202 {
 203         struct snd_pcm_runtime *runtime = substream->runtime;
 204         struct omap_runtime_data *prtd = runtime->private_data;
 205         unsigned long flags;
 206         int ret = 0;
 207
 208         spin_lock_irqsave(&prtd->lock, flags);
 209         switch (cmd) {
 210         case SNDRV_PCM_TRIGGER_START:
 211         case SNDRV_PCM_TRIGGER_RESUME:
 212         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 213                 prtd->period_index = 0;
 214                 omap_start_dma(prtd->dma_ch);
 215                 break;
 216
 217         case SNDRV_PCM_TRIGGER_STOP:
 218         case SNDRV_PCM_TRIGGER_SUSPEND:
 219         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 220                 prtd->period_index = -1;
 221                 omap_stop_dma(prtd->dma_ch);
 222                 break;
 223         default:
 224                 ret = -EINVAL;
 225         }
 226         spin_unlock_irqrestore(&prtd->lock, flags);
 227
 228         return ret;
 229 }
 230
 231 static snd_pcm_uframes_t omap_pcm_pointer(struct snd_pcm_substream *substream)
 232 {
 233         struct snd_pcm_runtime *runtime = substream->runtime;
 234         struct omap_runtime_data *prtd = runtime->private_data;
 235         dma_addr_t ptr;
 236         snd_pcm_uframes_t offset;
 237
 238         if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) {
 239                 ptr = omap_get_dma_dst_pos(prtd->dma_ch);
 240                 offset = bytes_to_frames(runtime, ptr - runtime->dma_addr);
 241         } else if (!(cpu_is_omap1510())) {
 242                 ptr = omap_get_dma_src_pos(prtd->dma_ch);
 243                 offset = bytes_to_frames(runtime, ptr - runtime->dma_addr);
 244         } else
 245                 offset = prtd->period_index * runtime->period_size;
 246
 247         if (offset >= runtime->buffer_size)
 248                 offset = 0;
 249
 250         return offset;
 251 }
 252
 253 static int omap_pcm_open(struct snd_pcm_substream *substream)
 254 {
 255         struct snd_pcm_runtime *runtime = substream->runtime;
 256         struct omap_runtime_data *prtd;
 257         int ret;
 258
 259         snd_soc_set_runtime_hwparams(substream, &omap_pcm_hardware);
 260
 261         /* Ensure that buffer size is a multiple of period size */
 262         ret = snd_pcm_hw_constraint_integer(runtime,
 263                                             SNDRV_PCM_HW_PARAM_PERIODS);
 264         if (ret < 0)
 265                 goto out;
 266
 267         prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
 268         if (prtd == NULL) {
 269                 ret = -ENOMEM;
 270                 goto out;
 271         }
 272         spin_lock_init(&prtd->lock);
 273         runtime->private_data = prtd;
 274
 275 out:
 276         return ret;
 277 }
 278
 279 static int omap_pcm_close(struct snd_pcm_substream *substream)
 280 {
 281         struct snd_pcm_runtime *runtime = substream->runtime;
 282
 283         kfree(runtime->private_data);
 284         return 0;
 285 }
 286
 287 static int omap_pcm_mmap(struct snd_pcm_substream *substream,
 288         struct vm_area_struct *vma)
 289 {
 290         struct snd_pcm_runtime *runtime = substream->runtime;
 291
 292         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 293                                      runtime->dma_area,
 294                                      runtime->dma_addr,
 295                                      runtime->dma_bytes);
 296 }
 297
 298 static struct snd_pcm_ops omap_pcm_ops = {
 299         .open           = omap_pcm_open,
 300         .close          = omap_pcm_close,
 301         .ioctl          = snd_pcm_lib_ioctl,
 302         .hw_params      = omap_pcm_hw_params,
 303         .hw_free        = omap_pcm_hw_free,
 304         .prepare        = omap_pcm_prepare,
 305         .trigger        = omap_pcm_trigger,
 306         .pointer        = omap_pcm_pointer,
 307         .mmap           = omap_pcm_mmap,
 308 };
 309
 310 static u64 omap_pcm_dmamask = DMA_BIT_MASK(32);
 311
 312 static int omap_pcm_preallocate_dma_buffer(struct snd_pcm *pcm,
 313         int stream)
 314 {
 315         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 316         struct snd_dma_buffer *buf = &substream->dma_buffer;
 317         size_t size = omap_pcm_hardware.buffer_bytes_max;
 318
 319         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 320         buf->dev.dev = pcm->card->dev;
 321         buf->private_data = NULL;
 322         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 323                                            &buf->addr, GFP_KERNEL);
 324         if (!buf->area)
 325                 return -ENOMEM;
 326
 327         buf->bytes = size;
 328         return 0;
 329 }
 330
 331 static void omap_pcm_free_dma_buffers(struct snd_pcm *pcm)
 332 {
 333         struct snd_pcm_substream *substream;
 334         struct snd_dma_buffer *buf;
 335         int stream;
 336
 337         for (stream = 0; stream < 2; stream++) {
 338                 substream = pcm->streams[stream].substream;
 339                 if (!substream)
 340                         continue;
 341
 342                 buf = &substream->dma_buffer;
 343                 if (!buf->area)
 344                         continue;
 345
 346                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 347                                       buf->area, buf->addr);
 348                 buf->area = NULL;
 349         }
 350 }
 351
 352 static int omap_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
 353                  struct snd_pcm *pcm)
 354 {
 355         int ret = 0;
 356
 357         if (!card->dev->dma_mask)
 358                 card->dev->dma_mask = &omap_pcm_dmamask;
 359         if (!card->dev->coherent_dma_mask)
 360                 card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
 361
 362         if (dai->playback.channels_min) {
 363                 ret = omap_pcm_preallocate_dma_buffer(pcm,
 364                         SNDRV_PCM_STREAM_PLAYBACK);
 365                 if (ret)
 366                         goto out;
 367         }
 368
 369         if (dai->capture.channels_min) {
 370                 ret = omap_pcm_preallocate_dma_buffer(pcm,
 371                         SNDRV_PCM_STREAM_CAPTURE);
 372                 if (ret)
 373                         goto out;
 374         }
 375
 376 out:
 377         return ret;
 378 }
 379
 380 struct snd_soc_platform omap_soc_platform = {
 381         .name           = "omap-pcm-audio",
 382         .pcm_ops        = &omap_pcm_ops,
 383         .pcm_new        = omap_pcm_new,
 384         .pcm_free       = omap_pcm_free_dma_buffers,
 385 };
 386 EXPORT_SYMBOL_GPL(omap_soc_platform);
 387
 388 static int __init omap_soc_platform_init(void)
 389 {
 390         return snd_soc_register_platform(&omap_soc_platform);
 391 }
 392 module_init(omap_soc_platform_init);
 393
 394 static void __exit omap_soc_platform_exit(void)
 395 {
 396         snd_soc_unregister_platform(&omap_soc_platform);
 397 }
 398 module_exit(omap_soc_platform_exit);
 399
 400 MODULE_AUTHOR("Jarkko Nikula <jhnikula@gmail.com>");
 401 MODULE_DESCRIPTION("OMAP PCM DMA module");
 402 MODULE_LICENSE("GPL");