sound/arm/pxa2xx-pcm.c

   1 /*
   2  * linux/sound/arm/pxa2xx-pcm.c -- ALSA PCM interface for the Intel PXA2xx chip
   3  *
   4  * Author:      Nicolas Pitre
   5  * Created:     Nov 30, 2004
   6  * Copyright:   (C) 2004 MontaVista Software, Inc.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/device.h>
  16 #include <linux/slab.h>
  17 #include <linux/dma-mapping.h>
  18
  19 #include <sound/core.h>
  20 #include <sound/pcm.h>
  21 #include <sound/pcm_params.h>
  22
  23 #include <asm/dma.h>
  24 #include <asm/hardware.h>
  25 #include <asm/arch/pxa-regs.h>
  26
  27 #include "pxa2xx-pcm.h"
  28
  29
  30 static const struct snd_pcm_hardware pxa2xx_pcm_hardware = {
  31         .info                   = SNDRV_PCM_INFO_MMAP |
  32                                   SNDRV_PCM_INFO_MMAP_VALID |
  33                                   SNDRV_PCM_INFO_INTERLEAVED |
  34                                   SNDRV_PCM_INFO_PAUSE,
  35         .formats                = SNDRV_PCM_FMTBIT_S16_LE,
  36         .period_bytes_min       = 32,
  37         .period_bytes_max       = 8192 - 32,
  38         .periods_min            = 1,
  39         .periods_max            = PAGE_SIZE/sizeof(pxa_dma_desc),
  40         .buffer_bytes_max       = 128 * 1024,
  41         .fifo_size              = 32,
  42 };
  43
  44 struct pxa2xx_runtime_data {
  45         int dma_ch;
  46         struct pxa2xx_pcm_dma_params *params;
  47         pxa_dma_desc *dma_desc_array;
  48         dma_addr_t dma_desc_array_phys;
  49 };
  50
  51 static int pxa2xx_pcm_hw_params(struct snd_pcm_substream *substream,
  52                                 struct snd_pcm_hw_params *params)
  53 {
  54         struct snd_pcm_runtime *runtime = substream->runtime;
  55         struct pxa2xx_runtime_data *rtd = runtime->private_data;
  56         size_t totsize = params_buffer_bytes(params);
  57         size_t period = params_period_bytes(params);
  58         pxa_dma_desc *dma_desc;
  59         dma_addr_t dma_buff_phys, next_desc_phys;
  60
  61         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
  62         runtime->dma_bytes = totsize;
  63
  64         dma_desc = rtd->dma_desc_array;
  65         next_desc_phys = rtd->dma_desc_array_phys;
  66         dma_buff_phys = runtime->dma_addr;
  67         do {
  68                 next_desc_phys += sizeof(pxa_dma_desc);
  69                 dma_desc->ddadr = next_desc_phys;
  70                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
  71                         dma_desc->dsadr = dma_buff_phys;
  72                         dma_desc->dtadr = rtd->params->dev_addr;
  73                 } else {
  74                         dma_desc->dsadr = rtd->params->dev_addr;
  75                         dma_desc->dtadr = dma_buff_phys;
  76                 }
  77                 if (period > totsize)
  78                         period = totsize;
  79                 dma_desc->dcmd = rtd->params->dcmd | period | DCMD_ENDIRQEN;
  80                 dma_desc++;
  81                 dma_buff_phys += period;
  82         } while (totsize -= period);
  83         dma_desc[-1].ddadr = rtd->dma_desc_array_phys;
  84
  85         return 0;
  86 }
  87
  88 static int pxa2xx_pcm_hw_free(struct snd_pcm_substream *substream)
  89 {
  90         struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
  91
  92         *rtd->params->drcmr = 0;
  93         snd_pcm_set_runtime_buffer(substream, NULL);
  94         return 0;
  95 }
  96
  97 static int pxa2xx_pcm_prepare(struct snd_pcm_substream *substream)
  98 {
  99         struct pxa2xx_pcm_client *client = substream->private_data;
 100         struct snd_pcm_runtime *runtime = substream->runtime;
 101         struct pxa2xx_runtime_data *rtd = runtime->private_data;
 102
 103         DCSR(rtd->dma_ch) &= ~DCSR_RUN;
 104         DCSR(rtd->dma_ch) = 0;
 105         DCMD(rtd->dma_ch) = 0;
 106         *rtd->params->drcmr = rtd->dma_ch | DRCMR_MAPVLD;
 107
 108         return client->prepare(substream);
 109 }
 110
 111 static int pxa2xx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
 112 {
 113         struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
 114         int ret = 0;
 115
 116         switch (cmd) {
 117         case SNDRV_PCM_TRIGGER_START:
 118                 DDADR(rtd->dma_ch) = rtd->dma_desc_array_phys;
 119                 DCSR(rtd->dma_ch) = DCSR_RUN;
 120                 break;
 121
 122         case SNDRV_PCM_TRIGGER_STOP:
 123         case SNDRV_PCM_TRIGGER_SUSPEND:
 124         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 125                 DCSR(rtd->dma_ch) &= ~DCSR_RUN;
 126                 break;
 127
 128         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 129                 DCSR(rtd->dma_ch) |= DCSR_RUN;
 130                 break;
 131
 132         default:
 133                 ret = -EINVAL;
 134         }
 135
 136         return ret;
 137 }
 138
 139 static void pxa2xx_pcm_dma_irq(int dma_ch, void *dev_id)
 140 {
 141         struct snd_pcm_substream *substream = dev_id;
 142         struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
 143         int dcsr;
 144
 145         dcsr = DCSR(dma_ch);
 146         DCSR(dma_ch) = dcsr & ~DCSR_STOPIRQEN;
 147
 148         if (dcsr & DCSR_ENDINTR) {
 149                 snd_pcm_period_elapsed(substream);
 150         } else {
 151                 printk( KERN_ERR "%s: DMA error on channel %d (DCSR=%#x)\n",
 152                         rtd->params->name, dma_ch, dcsr );
 153                 snd_pcm_stop(substream, SNDRV_PCM_STATE_XRUN);
 154         }
 155 }
 156
 157 static snd_pcm_uframes_t pxa2xx_pcm_pointer(struct snd_pcm_substream *substream)
 158 {
 159         struct snd_pcm_runtime *runtime = substream->runtime;
 160         struct pxa2xx_runtime_data *rtd = runtime->private_data;
 161         dma_addr_t ptr = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
 162                          DSADR(rtd->dma_ch) : DTADR(rtd->dma_ch);
 163         snd_pcm_uframes_t x = bytes_to_frames(runtime, ptr - runtime->dma_addr);
 164         if (x == runtime->buffer_size)
 165                 x = 0;
 166         return x;
 167 }
 168
 169 static int
 170 pxa2xx_pcm_hw_rule_mult32(struct snd_pcm_hw_params *params, struct snd_pcm_hw_rule *rule)
 171 {
 172         struct snd_interval *i = hw_param_interval(params, rule->var);
 173         int changed = 0;
 174
 175         if (i->min & 31) {
 176                 i->min = (i->min & ~31) + 32;
 177                 i->openmin = 0;
 178                 changed = 1;
 179         }
 180
 181         if (i->max & 31) {
 182                 i->max &= ~31;
 183                 i->openmax = 0;
 184                 changed = 1;
 185         }
 186
 187         return changed;
 188 }
 189
 190 static int pxa2xx_pcm_open(struct snd_pcm_substream *substream)
 191 {
 192         struct pxa2xx_pcm_client *client = substream->private_data;
 193         struct snd_pcm_runtime *runtime = substream->runtime;
 194         struct pxa2xx_runtime_data *rtd;
 195         int ret;
 196
 197         runtime->hw = pxa2xx_pcm_hardware;
 198
 199         /*
 200          * For mysterious reasons (and despite what the manual says)
 201          * playback samples are lost if the DMA count is not a multiple
 202          * of the DMA burst size.  Let's add a rule to enforce that.
 203          */
 204         ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
 205                                   pxa2xx_pcm_hw_rule_mult32, NULL,
 206                                   SNDRV_PCM_HW_PARAM_PERIOD_BYTES, -1);
 207         if (ret)
 208                 goto out;
 209         ret = snd_pcm_hw_rule_add(runtime, 0, SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
 210                                   pxa2xx_pcm_hw_rule_mult32, NULL,
 211                                   SNDRV_PCM_HW_PARAM_BUFFER_BYTES, -1);
 212         if (ret)
 213                 goto out;
 214
 215         ret = -ENOMEM;
 216         rtd = kmalloc(sizeof(*rtd), GFP_KERNEL);
 217         if (!rtd)
 218                 goto out;
 219         rtd->dma_desc_array =
 220                 dma_alloc_writecombine(substream->pcm->card->dev, PAGE_SIZE,
 221                                        &rtd->dma_desc_array_phys, GFP_KERNEL);
 222         if (!rtd->dma_desc_array)
 223                 goto err1;
 224
 225         rtd->params = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
 226                       client->playback_params : client->capture_params;
 227         ret = pxa_request_dma(rtd->params->name, DMA_PRIO_LOW,
 228                               pxa2xx_pcm_dma_irq, substream);
 229         if (ret < 0)
 230                 goto err2;
 231         rtd->dma_ch = ret;
 232
 233         runtime->private_data = rtd;
 234         ret = client->startup(substream);
 235         if (!ret)
 236                 goto out;
 237
 238         pxa_free_dma(rtd->dma_ch);
 239  err2:
 240         dma_free_writecombine(substream->pcm->card->dev, PAGE_SIZE,
 241                               rtd->dma_desc_array, rtd->dma_desc_array_phys);
 242  err1:
 243         kfree(rtd);
 244  out:
 245         return ret;
 246 }
 247
 248 static int pxa2xx_pcm_close(struct snd_pcm_substream *substream)
 249 {
 250         struct pxa2xx_pcm_client *client = substream->private_data;
 251         struct pxa2xx_runtime_data *rtd = substream->runtime->private_data;
 252
 253         pxa_free_dma(rtd->dma_ch);
 254         client->shutdown(substream);
 255         dma_free_writecombine(substream->pcm->card->dev, PAGE_SIZE,
 256                               rtd->dma_desc_array, rtd->dma_desc_array_phys);
 257         kfree(rtd);
 258         return 0;
 259 }
 260
 261 static int
 262 pxa2xx_pcm_mmap(struct snd_pcm_substream *substream, struct vm_area_struct *vma)
 263 {
 264         struct snd_pcm_runtime *runtime = substream->runtime;
 265         return dma_mmap_writecombine(substream->pcm->card->dev, vma,
 266                                      runtime->dma_area,
 267                                      runtime->dma_addr,
 268                                      runtime->dma_bytes);
 269 }
 270
 271 static struct snd_pcm_ops pxa2xx_pcm_ops = {
 272         .open           = pxa2xx_pcm_open,
 273         .close          = pxa2xx_pcm_close,
 274         .ioctl          = snd_pcm_lib_ioctl,
 275         .hw_params      = pxa2xx_pcm_hw_params,
 276         .hw_free        = pxa2xx_pcm_hw_free,
 277         .prepare        = pxa2xx_pcm_prepare,
 278         .trigger        = pxa2xx_pcm_trigger,
 279         .pointer        = pxa2xx_pcm_pointer,
 280         .mmap           = pxa2xx_pcm_mmap,
 281 };
 282
 283 static int pxa2xx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
 284 {
 285         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
 286         struct snd_dma_buffer *buf = &substream->dma_buffer;
 287         size_t size = pxa2xx_pcm_hardware.buffer_bytes_max;
 288         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 289         buf->dev.dev = pcm->card->dev;
 290         buf->private_data = NULL;
 291         buf->area = dma_alloc_writecombine(pcm->card->dev, size,
 292                                            &buf->addr, GFP_KERNEL);
 293         if (!buf->area)
 294                 return -ENOMEM;
 295         buf->bytes = size;
 296         return 0;
 297 }
 298
 299 static void pxa2xx_pcm_free_dma_buffers(struct snd_pcm *pcm)
 300 {
 301         struct snd_pcm_substream *substream;
 302         struct snd_dma_buffer *buf;
 303         int stream;
 304
 305         for (stream = 0; stream < 2; stream++) {
 306                 substream = pcm->streams[stream].substream;
 307                 if (!substream)
 308                         continue;
 309                 buf = &substream->dma_buffer;
 310                 if (!buf->area)
 311                         continue;
 312                 dma_free_writecombine(pcm->card->dev, buf->bytes,
 313                                       buf->area, buf->addr);
 314                 buf->area = NULL;
 315         }
 316 }
 317
 318 static u64 pxa2xx_pcm_dmamask = 0xffffffff;
 319
 320 int pxa2xx_pcm_new(struct snd_card *card, struct pxa2xx_pcm_client *client,
 321                    struct snd_pcm **rpcm)
 322 {
 323         struct snd_pcm *pcm;
 324         int play = client->playback_params ? 1 : 0;
 325         int capt = client->capture_params ? 1 : 0;
 326         int ret;
 327
 328         ret = snd_pcm_new(card, "PXA2xx-PCM", 0, play, capt, &pcm);
 329         if (ret)
 330                 goto out;
 331
 332         pcm->private_data = client;
 333         pcm->private_free = pxa2xx_pcm_free_dma_buffers;
 334
 335         if (!card->dev->dma_mask)
 336                 card->dev->dma_mask = &pxa2xx_pcm_dmamask;
 337         if (!card->dev->coherent_dma_mask)
 338                 card->dev->coherent_dma_mask = 0xffffffff;
 339
 340         if (play) {
 341                 int stream = SNDRV_PCM_STREAM_PLAYBACK;
 342                 snd_pcm_set_ops(pcm, stream, &pxa2xx_pcm_ops);
 343                 ret = pxa2xx_pcm_preallocate_dma_buffer(pcm, stream);
 344                 if (ret)
 345                         goto out;
 346         }
 347         if (capt) {
 348                 int stream = SNDRV_PCM_STREAM_CAPTURE;
 349                 snd_pcm_set_ops(pcm, stream, &pxa2xx_pcm_ops);
 350                 ret = pxa2xx_pcm_preallocate_dma_buffer(pcm, stream);
 351                 if (ret)
 352                         goto out;
 353         }
 354
 355         if (rpcm)
 356                 *rpcm = pcm;
 357         ret = 0;
 358
 359  out:
 360         return ret;
 361 }
 362
 363 EXPORT_SYMBOL(pxa2xx_pcm_new);
 364
 365 MODULE_AUTHOR("Nicolas Pitre");
 366 MODULE_DESCRIPTION("Intel PXA2xx PCM DMA module");
 367 MODULE_LICENSE("GPL");