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                 /*
  64                  * OMAP1510 doesn't support DMA chaining so have to restart
  65                  * the transfer after all periods are transferred
  66                  */
  67                 spin_lock_irqsave(&prtd->lock, flags);
  68                 if (prtd->period_index >= 0) {
  69                         if (++prtd->period_index == runtime->periods) {
  70                                 prtd->period_index = 0;
  71                                 omap_start_dma(prtd->dma_ch);
  72                         }
  73                 }
  74                 spin_unlock_irqrestore(&prtd->lock, flags);
  75         }
  76
  77         snd_pcm_period_elapsed(substream);
  78 }
  79
  80 /* this may get called several times by oss emulation */
  81 static int omap_pcm_hw_params(struct snd_pcm_substream *substream,
  82                               struct snd_pcm_hw_params *params)
  83 {
  84         struct snd_pcm_runtime *runtime = substream->runtime;
  85         struct snd_soc_pcm_runtime *rtd = substream->private_data;
  86         struct omap_runtime_data *prtd = runtime->private_data;
  87         struct omap_pcm_dma_data *dma_data = rtd->dai->cpu_dai->dma_data;
  88         int err = 0;
  89
  90         /* return if this is a bufferless transfer e.g.
  91          * codec <--> BT codec or GSM modem -- lg FIXME */
  92         if (!dma_data)
  93                 return 0;
  94
  95         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
  96         runtime->dma_bytes = params_buffer_bytes(params);
  97
  98         if (prtd->dma_data)
  99                 return 0;
 100         prtd->dma_data = dma_data;
 101         err = omap_request_dma(dma_data->dma_req, dma_data->name,
 102                                omap_pcm_dma_irq, substream, &prtd->dma_ch);
 103         if (!err && !cpu_is_omap1510()) {
 104                 /*
 105                  * Link channel with itself so DMA doesn't need any
 106                  * reprogramming while looping the buffer
 107                  */
 108                 omap_dma_link_lch(prtd->dma_ch, prtd->dma_ch);
 109         }
 110
 111         return err;
 112 }
 113
 114 static int omap_pcm_hw_free(struct snd_pcm_substream *substream)
 115 {
 116         struct snd_pcm_runtime *runtime = substream->runtime;
 117         struct omap_runtime_data *prtd = runtime->private_data;
 118
 119         if (prtd->dma_data == NULL)
 120                 return 0;
 121
 122         if (!cpu_is_omap1510())
 123                 omap_dma_unlink_lch(prtd->dma_ch, prtd->dma_ch);
 124         omap_free_dma(prtd->dma_ch);
 125         prtd->dma_data = NULL;
 126
 127         snd_pcm_set_runtime_buffer(substream, NULL);
 128
 129         return 0;
 130 }
 131
 132 static int omap_pcm_prepare(struct snd_pcm_substream *substream)
 133 {
 134         struct snd_pcm_runtime *runtime = substream->runtime;
 135         struct omap_runtime_data *prtd = runtime->private_data;
 136         struct omap_pcm_dma_data *dma_data = prtd->dma_data;
 137         struct omap_dma_channel_params dma_params;
 138
 139         /* return if this is a bufferless transfer e.g.
 140          * codec <--> BT codec or GSM modem -- lg FIXME */
 141         if (!prtd->dma_data)
 142                 return 0;
 143
 144         memset(&dma_params, 0, sizeof(dma_params));
 145         /*
 146          * Note: Regardless of interface data formats supported by OMAP McBSP
 147          * or EAC blocks, internal representation is always fixed 16-bit/sample
 148          */
 149         dma_params.data_type                    = OMAP_DMA_DATA_TYPE_S16;
 150         dma_params.trigger                      = dma_data->dma_req;
 151         dma_params.sync_mode                    = OMAP_DMA_SYNC_ELEMENT;
 152         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 153                 dma_params.src_amode            = OMAP_DMA_AMODE_POST_INC;
 154                 dma_params.dst_amode            = OMAP_DMA_AMODE_CONSTANT;
 155                 dma_params.src_or_dst_synch     = OMAP_DMA_DST_SYNC;
 156                 dma_params.src_start            = runtime->dma_addr;
 157                 dma_params.dst_start            = dma_data->port_addr;
 158                 dma_params.dst_port             = OMAP_DMA_PORT_MPUI;
 159         } else {
 160                 dma_params.src_amode            = OMAP_DMA_AMODE_CONSTANT;
 161                 dma_params.dst_amode            = OMAP_DMA_AMODE_POST_INC;
 162                 dma_params.src_or_dst_synch     = OMAP_DMA_SRC_SYNC;
 163                 dma_params.src_start            = dma_data->port_addr;
 164                 dma_params.dst_start            = runtime->dma_addr;
 165                 dma_params.src_port             = OMAP_DMA_PORT_MPUI;
 166         }
 167         /*
 168          * Set DMA transfer frame size equal to ALSA period size and frame
 169          * count as no. of ALSA periods. Then with DMA frame interrupt enabled,
 170          * we can transfer the whole ALSA buffer with single DMA transfer but
 171          * still can get an interrupt at each period bounary
 172          */
 173         dma_params.elem_count   = snd_pcm_lib_period_bytes(substream) / 2;
 174         dma_params.frame_count  = runtime->periods;
 175         omap_set_dma_params(prtd->dma_ch, &dma_params);
 176
 177         omap_enable_dma_irq(prtd->dma_ch, OMAP_DMA_FRAME_IRQ);
 178
 179         return 0;
 180 }
 181
 182 static int omap_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 183 {
 184         struct snd_pcm_runtime *runtime = substream->runtime;
 185         struct omap_runtime_data *prtd = runtime->private_data;
 186         unsigned long flags;
 187         int ret = 0;
 188
 189         spin_lock_irqsave(&prtd->lock, flags);
 190         switch (cmd) {
 191         case SNDRV_PCM_TRIGGER_START:
 192         case SNDRV_PCM_TRIGGER_RESUME:
 193         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 194                 prtd->period_index = 0;
 195                 omap_start_dma(prtd->dma_ch);
 196                 break;
 197
 198         case SNDRV_PCM_TRIGGER_STOP:
 199         case SNDRV_PCM_TRIGGER_SUSPEND:
 200         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 201                 prtd->period_index = -1;
 202                 omap_stop_dma(prtd->dma_ch);
 203                 break;
 204         default:
 205                 ret = -EINVAL;
 206         }
 207         spin_unlock_irqrestore(&prtd->lock, flags);
 208
 209         return ret;
 210 }
 211
 212 static snd_pcm_uframes_t omap_pcm_pointer(struct snd_pcm_substream *substream)
 213 {
 214         struct snd_pcm_runtime *runtime = substream->runtime;
 215         struct omap_runtime_data *prtd = runtime->private_data;
 216         dma_addr_t ptr;
 217         snd_pcm_uframes_t offset;
 218
 219         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 220                 ptr = omap_get_dma_src_pos(prtd->dma_ch);
 221         else
 222                 ptr = omap_get_dma_dst_pos(prtd->dma_ch);
 223
 224         offset = bytes_to_frames(runtime, ptr - runtime->dma_addr);
 225         if (offset >= runtime->buffer_size)
 226                 offset = 0;
 227
 228         return offset;
 229 }
 230
 231 static int omap_pcm_open(struct snd_pcm_substream *substream)
 232 {
 233         struct snd_pcm_runtime *runtime = substream->runtime;
 234         struct omap_runtime_data *prtd;
 235         int ret;
 236
 237         snd_soc_set_runtime_hwparams(substream, &omap_pcm_hardware);
 238
 239         /* Ensure that buffer size is a multiple of period size */
 240         ret = snd_pcm_hw_constraint_integer(runtime,
 241                                             SNDRV_PCM_HW_PARAM_PERIODS);
 242         if (ret < 0)
 243                 goto out;
 244
 245         prtd = kzalloc(sizeof(*prtd), GFP_KERNEL);
 246         if (prtd == NULL) {
 247                 ret = -ENOMEM;
 248                 goto out;
 249         }
 250         spin_lock_init(&prtd->lock);
 251         runtime->private_data = prtd;
 252
 253 out:
 254         return ret;
 255 }
 256
 257 static int omap_pcm_close(struct snd_pcm_substream *substream)
 258 {
 259         struct snd_pcm_runtime *runtime = substream->runtime;
 260
 261         kfree(runtime->private_data);
 262         return 0;
 263 }
 264
 265 static int omap_pcm_mmap(struct snd_pcm_substream *substream,
 266         struct vm_area_struct *vma)
 267 {
 268         struct snd_pcm_runtime *runtime = substream->runtime;
 269
 270         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 271                                      runtime->dma_area,
 272                                      runtime->dma_addr,
 273                                      runtime->dma_bytes);
 274 }
 275
 276 static struct snd_pcm_ops omap_pcm_ops = {
 277         .open           = omap_pcm_open,
 278         .close          = omap_pcm_close,
 279         .ioctl          = snd_pcm_lib_ioctl,
 280         .hw_params      = omap_pcm_hw_params,
 281         .hw_free        = omap_pcm_hw_free,
 282         .prepare        = omap_pcm_prepare,
 283         .trigger        = omap_pcm_trigger,
 284         .pointer        = omap_pcm_pointer,
 285         .mmap           = omap_pcm_mmap,
 286 };
 287
 288 static u64 omap_pcm_dmamask = DMA_BIT_MASK(32);
 289
 290 static int omap_pcm_preallocate_dma_buffer(struct snd_pcm *pcm,
 291         int stream)
 292 {
 293         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 294         struct snd_dma_buffer *buf = &substream->dma_buffer;
 295         size_t size = omap_pcm_hardware.buffer_bytes_max;
 296
 297         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 298         buf->dev.dev = pcm->card->dev;
 299         buf->private_data = NULL;
 300         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 301                                            &buf->addr, GFP_KERNEL);
 302         if (!buf->area)
 303                 return -ENOMEM;
 304
 305         buf->bytes = size;
 306         return 0;
 307 }
 308
 309 static void omap_pcm_free_dma_buffers(struct snd_pcm *pcm)
 310 {
 311         struct snd_pcm_substream *substream;
 312         struct snd_dma_buffer *buf;
 313         int stream;
 314
 315         for (stream = 0; stream < 2; stream++) {
 316                 substream = pcm->streams[stream].substream;
 317                 if (!substream)
 318                         continue;
 319
 320                 buf = &substream->dma_buffer;
 321                 if (!buf->area)
 322                         continue;
 323
 324                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 325                                       buf->area, buf->addr);
 326                 buf->area = NULL;
 327         }
 328 }
 329
 330 int omap_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
 331                  struct snd_pcm *pcm)
 332 {
 333         int ret = 0;
 334
 335         if (!card->dev->dma_mask)
 336                 card->dev->dma_mask = &omap_pcm_dmamask;
 337         if (!card->dev->coherent_dma_mask)
 338                 card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
 339
 340         if (dai->playback.channels_min) {
 341                 ret = omap_pcm_preallocate_dma_buffer(pcm,
 342                         SNDRV_PCM_STREAM_PLAYBACK);
 343                 if (ret)
 344                         goto out;
 345         }
 346
 347         if (dai->capture.channels_min) {
 348                 ret = omap_pcm_preallocate_dma_buffer(pcm,
 349                         SNDRV_PCM_STREAM_CAPTURE);
 350                 if (ret)
 351                         goto out;
 352         }
 353
 354 out:
 355         return ret;
 356 }
 357
 358 struct snd_soc_platform omap_soc_platform = {
 359         .name           = "omap-pcm-audio",
 360         .pcm_ops        = &omap_pcm_ops,
 361         .pcm_new        = omap_pcm_new,
 362         .pcm_free       = omap_pcm_free_dma_buffers,
 363 };
 364 EXPORT_SYMBOL_GPL(omap_soc_platform);
 365
 366 static int __init omap_soc_platform_init(void)
 367 {
 368         return snd_soc_register_platform(&omap_soc_platform);
 369 }
 370 module_init(omap_soc_platform_init);
 371
 372 static void __exit omap_soc_platform_exit(void)
 373 {
 374         snd_soc_unregister_platform(&omap_soc_platform);
 375 }
 376 module_exit(omap_soc_platform_exit);
 377
 378 MODULE_AUTHOR("Jarkko Nikula <jhnikula@gmail.com>");
 379 MODULE_DESCRIPTION("OMAP PCM DMA module");
 380 MODULE_LICENSE("GPL");