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