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