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 short src_cidx, dst_cidx;
  70         unsigned int data_type;
  71         unsigned short acnt;
  72         unsigned int count;
  73         unsigned int fifo_level;
  74
  75         period_size = snd_pcm_lib_period_bytes(substream);
  76         dma_offset = prtd->period * period_size;
  77         dma_pos = runtime->dma_addr + dma_offset;
  78         fifo_level = prtd->params->fifo_level;
  79
  80         pr_debug("davinci_pcm: audio_set_dma_params_play channel = %d "
  81                 "dma_ptr = %x period_size=%x\n", lch, dma_pos, period_size);
  82
  83         data_type = prtd->params->data_type;
  84         count = period_size / data_type;
  85         if (fifo_level)
  86                 count /= fifo_level;
  87
  88         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  89                 src = dma_pos;
  90                 dst = prtd->params->dma_addr;
  91                 src_bidx = data_type;
  92                 dst_bidx = 0;
  93                 src_cidx = data_type * fifo_level;
  94                 dst_cidx = 0;
  95         } else {
  96                 src = prtd->params->dma_addr;
  97                 dst = dma_pos;
  98                 src_bidx = 0;
  99                 dst_bidx = data_type;
 100                 src_cidx = 0;
 101                 dst_cidx = data_type * fifo_level;
 102         }
 103
 104         acnt = prtd->params->acnt;
 105         edma_set_src(lch, src, INCR, W8BIT);
 106         edma_set_dest(lch, dst, INCR, W8BIT);
 107
 108         edma_set_src_index(lch, src_bidx, src_cidx);
 109         edma_set_dest_index(lch, dst_bidx, dst_cidx);
 110
 111         if (!fifo_level)
 112                 edma_set_transfer_params(lch, acnt, count, 1, 0, ASYNC);
 113         else
 114                 edma_set_transfer_params(lch, acnt, fifo_level, count,
 115                                                         fifo_level, ABSYNC);
 116
 117         prtd->period++;
 118         if (unlikely(prtd->period >= runtime->periods))
 119                 prtd->period = 0;
 120 }
 121
 122 static void davinci_pcm_dma_irq(unsigned lch, u16 ch_status, void *data)
 123 {
 124         struct snd_pcm_substream *substream = data;
 125         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 126
 127         pr_debug("davinci_pcm: lch=%d, status=0x%x\n", lch, ch_status);
 128
 129         if (unlikely(ch_status != DMA_COMPLETE))
 130                 return;
 131
 132         if (snd_pcm_running(substream)) {
 133                 snd_pcm_period_elapsed(substream);
 134
 135                 spin_lock(&prtd->lock);
 136                 davinci_pcm_enqueue_dma(substream);
 137                 spin_unlock(&prtd->lock);
 138         }
 139 }
 140
 141 static int davinci_pcm_dma_request(struct snd_pcm_substream *substream)
 142 {
 143         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 144         struct edmacc_param p_ram;
 145         int ret;
 146
 147         /* Request master DMA channel */
 148         ret = edma_alloc_channel(prtd->params->channel,
 149                                   davinci_pcm_dma_irq, substream,
 150                                   EVENTQ_0);
 151         if (ret < 0)
 152                 return ret;
 153         prtd->master_lch = ret;
 154
 155         /* Request parameter RAM reload slot */
 156         ret = edma_alloc_slot(EDMA_SLOT_ANY);
 157         if (ret < 0) {
 158                 edma_free_channel(prtd->master_lch);
 159                 return ret;
 160         }
 161         prtd->slave_lch = ret;
 162
 163         /* Issue transfer completion IRQ when the channel completes a
 164          * transfer, then always reload from the same slot (by a kind
 165          * of loopback link).  The completion IRQ handler will update
 166          * the reload slot with a new buffer.
 167          *
 168          * REVISIT save p_ram here after setting up everything except
 169          * the buffer and its length (ccnt) ... use it as a template
 170          * so davinci_pcm_enqueue_dma() takes less time in IRQ.
 171          */
 172         edma_read_slot(prtd->slave_lch, &p_ram);
 173         p_ram.opt |= TCINTEN | EDMA_TCC(prtd->master_lch);
 174         p_ram.link_bcntrld = prtd->slave_lch << 5;
 175         edma_write_slot(prtd->slave_lch, &p_ram);
 176
 177         return 0;
 178 }
 179
 180 static int davinci_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 181 {
 182         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 183         int ret = 0;
 184
 185         spin_lock(&prtd->lock);
 186
 187         switch (cmd) {
 188         case SNDRV_PCM_TRIGGER_START:
 189         case SNDRV_PCM_TRIGGER_RESUME:
 190         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 191                 edma_start(prtd->master_lch);
 192                 break;
 193         case SNDRV_PCM_TRIGGER_STOP:
 194         case SNDRV_PCM_TRIGGER_SUSPEND:
 195         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 196                 edma_stop(prtd->master_lch);
 197                 break;
 198         default:
 199                 ret = -EINVAL;
 200                 break;
 201         }
 202
 203         spin_unlock(&prtd->lock);
 204
 205         return ret;
 206 }
 207
 208 static int davinci_pcm_prepare(struct snd_pcm_substream *substream)
 209 {
 210         struct davinci_runtime_data *prtd = substream->runtime->private_data;
 211         struct edmacc_param temp;
 212
 213         prtd->period = 0;
 214         davinci_pcm_enqueue_dma(substream);
 215
 216         /* Copy self-linked parameter RAM entry into master channel */
 217         edma_read_slot(prtd->slave_lch, &temp);
 218         edma_write_slot(prtd->master_lch, &temp);
 219         davinci_pcm_enqueue_dma(substream);
 220
 221         return 0;
 222 }
 223
 224 static snd_pcm_uframes_t
 225 davinci_pcm_pointer(struct snd_pcm_substream *substream)
 226 {
 227         struct snd_pcm_runtime *runtime = substream->runtime;
 228         struct davinci_runtime_data *prtd = runtime->private_data;
 229         unsigned int offset;
 230         dma_addr_t count;
 231         dma_addr_t src, dst;
 232
 233         spin_lock(&prtd->lock);
 234
 235         edma_get_position(prtd->master_lch, &src, &dst);
 236         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 237                 count = src - runtime->dma_addr;
 238         else
 239                 count = dst - runtime->dma_addr;
 240
 241         spin_unlock(&prtd->lock);
 242
 243         offset = bytes_to_frames(runtime, count);
 244         if (offset >= runtime->buffer_size)
 245                 offset = 0;
 246
 247         return offset;
 248 }
 249
 250 static int davinci_pcm_open(struct snd_pcm_substream *substream)
 251 {
 252         struct snd_pcm_runtime *runtime = substream->runtime;
 253         struct davinci_runtime_data *prtd;
 254         int ret = 0;
 255         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 256         struct davinci_pcm_dma_params *pa = rtd->dai->cpu_dai->private_data;
 257         struct davinci_pcm_dma_params *params = &pa[substream->stream];
 258         if (!params)
 259                 return -ENODEV;
 260
 261         snd_soc_set_runtime_hwparams(substream, &davinci_pcm_hardware);
 262         /* ensure that buffer size is a multiple of period size */
 263         ret = snd_pcm_hw_constraint_integer(runtime,
 264                                                 SNDRV_PCM_HW_PARAM_PERIODS);
 265         if (ret < 0)
 266                 return ret;
 267
 268         prtd = kzalloc(sizeof(struct davinci_runtime_data), GFP_KERNEL);
 269         if (prtd == NULL)
 270                 return -ENOMEM;
 271
 272         spin_lock_init(&prtd->lock);
 273         prtd->params = params;
 274
 275         runtime->private_data = prtd;
 276
 277         ret = davinci_pcm_dma_request(substream);
 278         if (ret) {
 279                 printk(KERN_ERR "davinci_pcm: Failed to get dma channels\n");
 280                 kfree(prtd);
 281         }
 282
 283         return ret;
 284 }
 285
 286 static int davinci_pcm_close(struct snd_pcm_substream *substream)
 287 {
 288         struct snd_pcm_runtime *runtime = substream->runtime;
 289         struct davinci_runtime_data *prtd = runtime->private_data;
 290
 291         edma_unlink(prtd->slave_lch);
 292
 293         edma_free_slot(prtd->slave_lch);
 294         edma_free_channel(prtd->master_lch);
 295
 296         kfree(prtd);
 297
 298         return 0;
 299 }
 300
 301 static int davinci_pcm_hw_params(struct snd_pcm_substream *substream,
 302                                  struct snd_pcm_hw_params *hw_params)
 303 {
 304         return snd_pcm_lib_malloc_pages(substream,
 305                                         params_buffer_bytes(hw_params));
 306 }
 307
 308 static int davinci_pcm_hw_free(struct snd_pcm_substream *substream)
 309 {
 310         return snd_pcm_lib_free_pages(substream);
 311 }
 312
 313 static int davinci_pcm_mmap(struct snd_pcm_substream *substream,
 314                             struct vm_area_struct *vma)
 315 {
 316         struct snd_pcm_runtime *runtime = substream->runtime;
 317
 318         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 319                                      runtime->dma_area,
 320                                      runtime->dma_addr,
 321                                      runtime->dma_bytes);
 322 }
 323
 324 static struct snd_pcm_ops davinci_pcm_ops = {
 325         .open =         davinci_pcm_open,
 326         .close =        davinci_pcm_close,
 327         .ioctl =        snd_pcm_lib_ioctl,
 328         .hw_params =    davinci_pcm_hw_params,
 329         .hw_free =      davinci_pcm_hw_free,
 330         .prepare =      davinci_pcm_prepare,
 331         .trigger =      davinci_pcm_trigger,
 332         .pointer =      davinci_pcm_pointer,
 333         .mmap =         davinci_pcm_mmap,
 334 };
 335
 336 static int davinci_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 337 {
 338         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 339         struct snd_dma_buffer *buf = &substream->dma_buffer;
 340         size_t size = davinci_pcm_hardware.buffer_bytes_max;
 341
 342         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 343         buf->dev.dev = pcm->card->dev;
 344         buf->private_data = NULL;
 345         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 346                                            &buf->addr, GFP_KERNEL);
 347
 348         pr_debug("davinci_pcm: preallocate_dma_buffer: area=%p, addr=%p, "
 349                 "size=%d\n", (void *) buf->area, (void *) buf->addr, size);
 350
 351         if (!buf->area)
 352                 return -ENOMEM;
 353
 354         buf->bytes = size;
 355         return 0;
 356 }
 357
 358 static void davinci_pcm_free(struct snd_pcm *pcm)
 359 {
 360         struct snd_pcm_substream *substream;
 361         struct snd_dma_buffer *buf;
 362         int stream;
 363
 364         for (stream = 0; stream < 2; stream++) {
 365                 substream = pcm->streams[stream].substream;
 366                 if (!substream)
 367                         continue;
 368
 369                 buf = &substream->dma_buffer;
 370                 if (!buf->area)
 371                         continue;
 372
 373                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 374                                       buf->area, buf->addr);
 375                 buf->area = NULL;
 376         }
 377 }
 378
 379 static u64 davinci_pcm_dmamask = 0xffffffff;
 380
 381 static int davinci_pcm_new(struct snd_card *card,
 382                            struct snd_soc_dai *dai, struct snd_pcm *pcm)
 383 {
 384         int ret;
 385
 386         if (!card->dev->dma_mask)
 387                 card->dev->dma_mask = &davinci_pcm_dmamask;
 388         if (!card->dev->coherent_dma_mask)
 389                 card->dev->coherent_dma_mask = 0xffffffff;
 390
 391         if (dai->playback.channels_min) {
 392                 ret = davinci_pcm_preallocate_dma_buffer(pcm,
 393                         SNDRV_PCM_STREAM_PLAYBACK);
 394                 if (ret)
 395                         return ret;
 396         }
 397
 398         if (dai->capture.channels_min) {
 399                 ret = davinci_pcm_preallocate_dma_buffer(pcm,
 400                         SNDRV_PCM_STREAM_CAPTURE);
 401                 if (ret)
 402                         return ret;
 403         }
 404
 405         return 0;
 406 }
 407
 408 struct snd_soc_platform davinci_soc_platform = {
 409         .name =         "davinci-audio",
 410         .pcm_ops =      &davinci_pcm_ops,
 411         .pcm_new =      davinci_pcm_new,
 412         .pcm_free =     davinci_pcm_free,
 413 };
 414 EXPORT_SYMBOL_GPL(davinci_soc_platform);
 415
 416 static int __init davinci_soc_platform_init(void)
 417 {
 418         return snd_soc_register_platform(&davinci_soc_platform);
 419 }
 420 module_init(davinci_soc_platform_init);
 421
 422 static void __exit davinci_soc_platform_exit(void)
 423 {
 424         snd_soc_unregister_platform(&davinci_soc_platform);
 425 }
 426 module_exit(davinci_soc_platform_exit);
 427
 428 MODULE_AUTHOR("Vladimir Barinov");
 429 MODULE_DESCRIPTION("TI DAVINCI PCM DMA module");
 430 MODULE_LICENSE("GPL");