sound/soc/davinci/davinci-pcm.c

   1 /*
   2  * ALSA PCM interface for the TI DAVINCI processor
   3  *
   4  * Author:      Vladimir Barinov, <vbarinov@embeddedalley.com>
   5  * Copyright:   (C) 2007 MontaVista Software, Inc., <source@mvista.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 version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/slab.h>
  16 #include <linux/dma-mapping.h>
  17 #include <linux/kernel.h>
  18
  19 #include <sound/core.h>
  20 #include <sound/pcm.h>
  21 #include <sound/pcm_params.h>
  22 #include <sound/soc.h>
  23
  24 #include <asm/dma.h>
  25 #include <mach/edma.h>
  26
  27 #include "davinci-pcm.h"
  28
  29 static struct snd_pcm_hardware davinci_pcm_hardware = {
  30         .info = (SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
  31                  SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
  32                  SNDRV_PCM_INFO_PAUSE),
  33         .formats = (SNDRV_PCM_FMTBIT_S16_LE),
  34         .rates = (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_16000 |
  35                   SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_32000 |
  36                   SNDRV_PCM_RATE_44100 | SNDRV_PCM_RATE_48000 |
  37                   SNDRV_PCM_RATE_88200 | SNDRV_PCM_RATE_96000 |
  38                   SNDRV_PCM_RATE_KNOT),
  39         .rate_min = 8000,
  40         .rate_max = 96000,
  41         .channels_min = 2,
  42         .channels_max = 2,
  43         .buffer_bytes_max = 128 * 1024,
  44         .period_bytes_min = 32,
  45         .period_bytes_max = 8 * 1024,
  46         .periods_min = 16,
  47         .periods_max = 255,
  48         .fifo_size = 0,
  49 };
  50
  51 struct davinci_runtime_data {
  52         spinlock_t lock;
  53         int period;             /* current DMA period */
  54         int master_lch;         /* Master DMA channel */
  55         int slave_lch;          /* linked parameter RAM reload slot */
  56         struct davinci_pcm_dma_params *params;  /* DMA params */
  57 };
  58
  59 static void davinci_pcm_enqueue_dma(struct snd_pcm_substream *substream)
  60 {
  61         struct davinci_runtime_data *prtd = substream->runtime->private_data;
  62         struct snd_pcm_runtime *runtime = substream->runtime;
  63         int lch = prtd->slave_lch;
  64         unsigned int period_size;
  65         unsigned int dma_offset;
  66         dma_addr_t dma_pos;
  67         dma_addr_t src, dst;
  68         unsigned short src_bidx, dst_bidx;
  69         unsigned int data_type;
  70         unsigned short acnt;
  71         unsigned int count;
  72
  73         period_size = snd_pcm_lib_period_bytes(substream);
  74         dma_offset = prtd->period * period_size;
  75         dma_pos = runtime->dma_addr + dma_offset;
  76
  77         pr_debug("davinci_pcm: audio_set_dma_params_play channel = %d "
  78                 "dma_ptr = %x period_size=%x\n", lch, dma_pos, period_size);
  79
  80         data_type = prtd->params->data_type;
  81         count = period_size / data_type;
  82
  83         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  84                 src = dma_pos;
  85                 dst = prtd->params->dma_addr;
  86                 src_bidx = data_type;
  87                 dst_bidx = 0;
  88         } else {
  89                 src = prtd->params->dma_addr;
  90                 dst = dma_pos;
  91                 src_bidx = 0;
  92                 dst_bidx = data_type;
  93         }
  94
  95         acnt = prtd->params->acnt;
  96         edma_set_src(lch, src, INCR, W8BIT);
  97         edma_set_dest(lch, dst, INCR, W8BIT);
  98         edma_set_src_index(lch, src_bidx, 0);
  99         edma_set_dest_index(lch, dst_bidx, 0);
 100         edma_set_transfer_params(lch, acnt, count, 1, 0, ASYNC);
 101
 102         prtd->period++;
 103         if (unlikely(prtd->period >= runtime->periods))
 104                 prtd->period = 0;
 105 }
 106
 107 static void davinci_pcm_dma_irq(unsigned lch, u16 ch_status, void *data)
 108 {
 109         struct snd_pcm_substream *substream = data;
 110         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 111
 112         pr_debug("davinci_pcm: lch=%d, status=0x%x\n", lch, ch_status);
 113
 114         if (unlikely(ch_status != DMA_COMPLETE))
 115                 return;
 116
 117         if (snd_pcm_running(substream)) {
 118                 snd_pcm_period_elapsed(substream);
 119
 120                 spin_lock(&prtd->lock);
 121                 davinci_pcm_enqueue_dma(substream);
 122                 spin_unlock(&prtd->lock);
 123         }
 124 }
 125
 126 static int davinci_pcm_dma_request(struct snd_pcm_substream *substream)
 127 {
 128         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 129         struct edmacc_param p_ram;
 130         int ret;
 131
 132         /* Request master DMA channel */
 133         ret = edma_alloc_channel(prtd->params->channel,
 134                                   davinci_pcm_dma_irq, substream,
 135                                   EVENTQ_0);
 136         if (ret < 0)
 137                 return ret;
 138         prtd->master_lch = ret;
 139
 140         /* Request parameter RAM reload slot */
 141         ret = edma_alloc_slot(EDMA_SLOT_ANY);
 142         if (ret < 0) {
 143                 edma_free_channel(prtd->master_lch);
 144                 return ret;
 145         }
 146         prtd->slave_lch = ret;
 147
 148         /* Issue transfer completion IRQ when the channel completes a
 149          * transfer, then always reload from the same slot (by a kind
 150          * of loopback link).  The completion IRQ handler will update
 151          * the reload slot with a new buffer.
 152          *
 153          * REVISIT save p_ram here after setting up everything except
 154          * the buffer and its length (ccnt) ... use it as a template
 155          * so davinci_pcm_enqueue_dma() takes less time in IRQ.
 156          */
 157         edma_read_slot(prtd->slave_lch, &p_ram);
 158         p_ram.opt |= TCINTEN | EDMA_TCC(prtd->master_lch);
 159         p_ram.link_bcntrld = prtd->slave_lch << 5;
 160         edma_write_slot(prtd->slave_lch, &p_ram);
 161
 162         return 0;
 163 }
 164
 165 static int davinci_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 166 {
 167         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 168         int ret = 0;
 169
 170         spin_lock(&prtd->lock);
 171
 172         switch (cmd) {
 173         case SNDRV_PCM_TRIGGER_START:
 174         case SNDRV_PCM_TRIGGER_RESUME:
 175         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 176                 edma_start(prtd->master_lch);
 177                 break;
 178         case SNDRV_PCM_TRIGGER_STOP:
 179         case SNDRV_PCM_TRIGGER_SUSPEND:
 180         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 181                 edma_stop(prtd->master_lch);
 182                 break;
 183         default:
 184                 ret = -EINVAL;
 185                 break;
 186         }
 187
 188         spin_unlock(&prtd->lock);
 189
 190         return ret;
 191 }
 192
 193 static int davinci_pcm_prepare(struct snd_pcm_substream *substream)
 194 {
 195         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 196         struct edmacc_param temp;
 197
 198         prtd->period = 0;
 199         davinci_pcm_enqueue_dma(substream);
 200
 201         /* Copy self-linked parameter RAM entry into master channel */
 202         edma_read_slot(prtd->slave_lch, &temp);
 203         edma_write_slot(prtd->master_lch, &temp);
 204         davinci_pcm_enqueue_dma(substream);
 205
 206         return 0;
 207 }
 208
 209 static snd_pcm_uframes_t
 210 davinci_pcm_pointer(struct snd_pcm_substream *substream)
 211 {
 212         struct snd_pcm_runtime *runtime = substream->runtime;
 213         struct davinci_runtime_data *prtd = runtime->private_data;
 214         unsigned int offset;
 215         dma_addr_t count;
 216         dma_addr_t src, dst;
 217
 218         spin_lock(&prtd->lock);
 219
 220         edma_get_position(prtd->master_lch, &src, &dst);
 221         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 222                 count = src - runtime->dma_addr;
 223         else
 224                 count = dst - runtime->dma_addr;
 225
 226         spin_unlock(&prtd->lock);
 227
 228         offset = bytes_to_frames(runtime, count);
 229         if (offset >= runtime->buffer_size)
 230                 offset = 0;
 231
 232         return offset;
 233 }
 234
 235 static int davinci_pcm_open(struct snd_pcm_substream *substream)
 236 {
 237         struct snd_pcm_runtime *runtime = substream->runtime;
 238         struct davinci_runtime_data *prtd;
 239         int ret = 0;
 240         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 241         struct davinci_pcm_dma_params *pa = rtd->dai->cpu_dai->private_data;
 242         struct davinci_pcm_dma_params *params = &pa[substream->stream];
 243         if (!params)
 244                 return -ENODEV;
 245
 246         snd_soc_set_runtime_hwparams(substream, &davinci_pcm_hardware);
 247         /* ensure that buffer size is a multiple of period size */
 248         ret = snd_pcm_hw_constraint_integer(runtime,
 249                                                 SNDRV_PCM_HW_PARAM_PERIODS);
 250         if (ret < 0)
 251                 return ret;
 252
 253         prtd = kzalloc(sizeof(struct davinci_runtime_data), GFP_KERNEL);
 254         if (prtd == NULL)
 255                 return -ENOMEM;
 256
 257         spin_lock_init(&prtd->lock);
 258         prtd->params = params;
 259
 260         runtime->private_data = prtd;
 261
 262         ret = davinci_pcm_dma_request(substream);
 263         if (ret) {
 264                 printk(KERN_ERR "davinci_pcm: Failed to get dma channels\n");
 265                 kfree(prtd);
 266         }
 267
 268         return ret;
 269 }
 270
 271 static int davinci_pcm_close(struct snd_pcm_substream *substream)
 272 {
 273         struct snd_pcm_runtime *runtime = substream->runtime;
 274         struct davinci_runtime_data *prtd = runtime->private_data;
 275
 276         edma_unlink(prtd->slave_lch);
 277
 278         edma_free_slot(prtd->slave_lch);
 279         edma_free_channel(prtd->master_lch);
 280
 281         kfree(prtd);
 282
 283         return 0;
 284 }
 285
 286 static int davinci_pcm_hw_params(struct snd_pcm_substream *substream,
 287                                  struct snd_pcm_hw_params *hw_params)
 288 {
 289         return snd_pcm_lib_malloc_pages(substream,
 290                                         params_buffer_bytes(hw_params));
 291 }
 292
 293 static int davinci_pcm_hw_free(struct snd_pcm_substream *substream)
 294 {
 295         return snd_pcm_lib_free_pages(substream);
 296 }
 297
 298 static int davinci_pcm_mmap(struct snd_pcm_substream *substream,
 299                             struct vm_area_struct *vma)
 300 {
 301         struct snd_pcm_runtime *runtime = substream->runtime;
 302
 303         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 304                                      runtime->dma_area,
 305                                      runtime->dma_addr,
 306                                      runtime->dma_bytes);
 307 }
 308
 309 static struct snd_pcm_ops davinci_pcm_ops = {
 310         .open =         davinci_pcm_open,
 311         .close =        davinci_pcm_close,
 312         .ioctl =        snd_pcm_lib_ioctl,
 313         .hw_params =    davinci_pcm_hw_params,
 314         .hw_free =      davinci_pcm_hw_free,
 315         .prepare =      davinci_pcm_prepare,
 316         .trigger =      davinci_pcm_trigger,
 317         .pointer =      davinci_pcm_pointer,
 318         .mmap =         davinci_pcm_mmap,
 319 };
 320
 321 static int davinci_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 322 {
 323         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 324         struct snd_dma_buffer *buf = &substream->dma_buffer;
 325         size_t size = davinci_pcm_hardware.buffer_bytes_max;
 326
 327         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 328         buf->dev.dev = pcm->card->dev;
 329         buf->private_data = NULL;
 330         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 331                                            &buf->addr, GFP_KERNEL);
 332
 333         pr_debug("davinci_pcm: preallocate_dma_buffer: area=%p, addr=%p, "
 334                 "size=%d\n", (void *) buf->area, (void *) buf->addr, size);
 335
 336         if (!buf->area)
 337                 return -ENOMEM;
 338
 339         buf->bytes = size;
 340         return 0;
 341 }
 342
 343 static void davinci_pcm_free(struct snd_pcm *pcm)
 344 {
 345         struct snd_pcm_substream *substream;
 346         struct snd_dma_buffer *buf;
 347         int stream;
 348
 349         for (stream = 0; stream < 2; stream++) {
 350                 substream = pcm->streams[stream].substream;
 351                 if (!substream)
 352                         continue;
 353
 354                 buf = &substream->dma_buffer;
 355                 if (!buf->area)
 356                         continue;
 357
 358                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 359                                       buf->area, buf->addr);
 360                 buf->area = NULL;
 361         }
 362 }
 363
 364 static u64 davinci_pcm_dmamask = 0xffffffff;
 365
 366 static int davinci_pcm_new(struct snd_card *card,
 367                            struct snd_soc_dai *dai, struct snd_pcm *pcm)
 368 {
 369         int ret;
 370
 371         if (!card->dev->dma_mask)
 372                 card->dev->dma_mask = &davinci_pcm_dmamask;
 373         if (!card->dev->coherent_dma_mask)
 374                 card->dev->coherent_dma_mask = 0xffffffff;
 375
 376         if (dai->playback.channels_min) {
 377                 ret = davinci_pcm_preallocate_dma_buffer(pcm,
 378                         SNDRV_PCM_STREAM_PLAYBACK);
 379                 if (ret)
 380                         return ret;
 381         }
 382
 383         if (dai->capture.channels_min) {
 384                 ret = davinci_pcm_preallocate_dma_buffer(pcm,
 385                         SNDRV_PCM_STREAM_CAPTURE);
 386                 if (ret)
 387                         return ret;
 388         }
 389
 390         return 0;
 391 }
 392
 393 struct snd_soc_platform davinci_soc_platform = {
 394         .name =         "davinci-audio",
 395         .pcm_ops =      &davinci_pcm_ops,
 396         .pcm_new =      davinci_pcm_new,
 397         .pcm_free =     davinci_pcm_free,
 398 };
 399 EXPORT_SYMBOL_GPL(davinci_soc_platform);
 400
 401 static int __init davinci_soc_platform_init(void)
 402 {
 403         return snd_soc_register_platform(&davinci_soc_platform);
 404 }
 405 module_init(davinci_soc_platform_init);
 406
 407 static void __exit davinci_soc_platform_exit(void)
 408 {
 409         snd_soc_unregister_platform(&davinci_soc_platform);
 410 }
 411 module_exit(davinci_soc_platform_exit);
 412
 413 MODULE_AUTHOR("Vladimir Barinov");
 414 MODULE_DESCRIPTION("TI DAVINCI PCM DMA module");
 415 MODULE_LICENSE("GPL");