sound/soc/atmel/atmel-pcm.c

   1 /*
   2  * atmel-pcm.c  --  ALSA PCM interface for the Atmel atmel SoC.
   3  *
   4  *  Copyright (C) 2005 SAN People
   5  *  Copyright (C) 2008 Atmel
   6  *
   7  * Authors: Sedji Gaouaou <sedji.gaouaou@atmel.com>
   8  *
   9  * Based on at91-pcm. by:
  10  * Frank Mandarino <fmandarino@endrelia.com>
  11  * Copyright 2006 Endrelia Technologies Inc.
  12  *
  13  * Based on pxa2xx-pcm.c by:
  14  *
  15  * Author:      Nicolas Pitre
  16  * Created:     Nov 30, 2004
  17  * Copyright:   (C) 2004 MontaVista Software, Inc.
  18  *
  19  * This program is free software; you can redistribute it and/or modify
  20  * it under the terms of the GNU General Public License as published by
  21  * the Free Software Foundation; either version 2 of the License, or
  22  * (at your option) any later version.
  23  *
  24  * This program is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with this program; if not, write to the Free Software
  31  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  32  */
  33
  34 #include <linux/module.h>
  35 #include <linux/init.h>
  36 #include <linux/platform_device.h>
  37 #include <linux/slab.h>
  38 #include <linux/dma-mapping.h>
  39 #include <linux/atmel_pdc.h>
  40 #include <linux/atmel-ssc.h>
  41
  42 #include <sound/core.h>
  43 #include <sound/pcm.h>
  44 #include <sound/pcm_params.h>
  45 #include <sound/soc.h>
  46
  47 #include "atmel-pcm.h"
  48
  49
  50 /*--------------------------------------------------------------------------*\
  51  * Hardware definition
  52 \*--------------------------------------------------------------------------*/
  53 /* TODO: These values were taken from the AT91 platform driver, check
  54  *       them against real values for AT32
  55  */
  56 static const struct snd_pcm_hardware atmel_pcm_hardware = {
  57         .info                   = SNDRV_PCM_INFO_MMAP |
  58                                   SNDRV_PCM_INFO_MMAP_VALID |
  59                                   SNDRV_PCM_INFO_INTERLEAVED |
  60                                   SNDRV_PCM_INFO_PAUSE,
  61         .formats                = SNDRV_PCM_FMTBIT_S16_LE,
  62         .period_bytes_min       = 32,
  63         .period_bytes_max       = 8192,
  64         .periods_min            = 2,
  65         .periods_max            = 1024,
  66         .buffer_bytes_max       = 32 * 1024,
  67 };
  68
  69
  70 /*--------------------------------------------------------------------------*\
  71  * Data types
  72 \*--------------------------------------------------------------------------*/
  73 struct atmel_runtime_data {
  74         struct atmel_pcm_dma_params *params;
  75         dma_addr_t dma_buffer;          /* physical address of dma buffer */
  76         dma_addr_t dma_buffer_end;      /* first address beyond DMA buffer */
  77         size_t period_size;
  78
  79         dma_addr_t period_ptr;          /* physical address of next period */
  80
  81         /* PDC register save */
  82         u32 pdc_xpr_save;
  83         u32 pdc_xcr_save;
  84         u32 pdc_xnpr_save;
  85         u32 pdc_xncr_save;
  86 };
  87
  88
  89 /*--------------------------------------------------------------------------*\
  90  * Helper functions
  91 \*--------------------------------------------------------------------------*/
  92 static int atmel_pcm_preallocate_dma_buffer(struct snd_pcm *pcm,
  93         int stream)
  94 {
  95         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
  96         struct snd_dma_buffer *buf = &substream->dma_buffer;
  97         size_t size = atmel_pcm_hardware.buffer_bytes_max;
  98
  99         buf->dev.type = SNDRV_DMA_TYPE_DEV;
 100         buf->dev.dev = pcm->card->dev;
 101         buf->private_data = NULL;
 102         buf->area = dma_alloc_coherent(pcm->card->dev, size,
 103                                           &buf->addr, GFP_KERNEL);
 104         pr_debug("atmel-pcm:"
 105                 "preallocate_dma_buffer: area=%p, addr=%p, size=%d\n",
 106                 (void *) buf->area,
 107                 (void *) buf->addr,
 108                 size);
 109
 110         if (!buf->area)
 111                 return -ENOMEM;
 112
 113         buf->bytes = size;
 114         return 0;
 115 }
 116 /*--------------------------------------------------------------------------*\
 117  * ISR
 118 \*--------------------------------------------------------------------------*/
 119 static void atmel_pcm_dma_irq(u32 ssc_sr,
 120         struct snd_pcm_substream *substream)
 121 {
 122         struct atmel_runtime_data *prtd = substream->runtime->private_data;
 123         struct atmel_pcm_dma_params *params = prtd->params;
 124         static int count;
 125
 126         count++;
 127
 128         if (ssc_sr & params->mask->ssc_endbuf) {
 129                 pr_warning("atmel-pcm: buffer %s on %s"
 130                                 " (SSC_SR=%#x, count=%d)\n",
 131                                 substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 132                                 ? "underrun" : "overrun",
 133                                 params->name, ssc_sr, count);
 134
 135                 /* re-start the PDC */
 136                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 137                            params->mask->pdc_disable);
 138                 prtd->period_ptr += prtd->period_size;
 139                 if (prtd->period_ptr >= prtd->dma_buffer_end)
 140                         prtd->period_ptr = prtd->dma_buffer;
 141
 142                 ssc_writex(params->ssc->regs, params->pdc->xpr,
 143                            prtd->period_ptr);
 144                 ssc_writex(params->ssc->regs, params->pdc->xcr,
 145                            prtd->period_size / params->pdc_xfer_size);
 146                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 147                            params->mask->pdc_enable);
 148         }
 149
 150         if (ssc_sr & params->mask->ssc_endx) {
 151                 /* Load the PDC next pointer and counter registers */
 152                 prtd->period_ptr += prtd->period_size;
 153                 if (prtd->period_ptr >= prtd->dma_buffer_end)
 154                         prtd->period_ptr = prtd->dma_buffer;
 155
 156                 ssc_writex(params->ssc->regs, params->pdc->xnpr,
 157                            prtd->period_ptr);
 158                 ssc_writex(params->ssc->regs, params->pdc->xncr,
 159                            prtd->period_size / params->pdc_xfer_size);
 160         }
 161
 162         snd_pcm_period_elapsed(substream);
 163 }
 164
 165
 166 /*--------------------------------------------------------------------------*\
 167  * PCM operations
 168 \*--------------------------------------------------------------------------*/
 169 static int atmel_pcm_hw_params(struct snd_pcm_substream *substream,
 170         struct snd_pcm_hw_params *params)
 171 {
 172         struct snd_pcm_runtime *runtime = substream->runtime;
 173         struct atmel_runtime_data *prtd = runtime->private_data;
 174         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 175
 176         /* this may get called several times by oss emulation
 177          * with different params */
 178
 179         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 180         runtime->dma_bytes = params_buffer_bytes(params);
 181
 182         prtd->params = snd_soc_dai_get_dma_data(rtd->dai->cpu_dai, substream);
 183         prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
 184
 185         prtd->dma_buffer = runtime->dma_addr;
 186         prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes;
 187         prtd->period_size = params_period_bytes(params);
 188
 189         pr_debug("atmel-pcm: "
 190                 "hw_params: DMA for %s initialized "
 191                 "(dma_bytes=%u, period_size=%u)\n",
 192                 prtd->params->name,
 193                 runtime->dma_bytes,
 194                 prtd->period_size);
 195         return 0;
 196 }
 197
 198 static int atmel_pcm_hw_free(struct snd_pcm_substream *substream)
 199 {
 200         struct atmel_runtime_data *prtd = substream->runtime->private_data;
 201         struct atmel_pcm_dma_params *params = prtd->params;
 202
 203         if (params != NULL) {
 204                 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
 205                            params->mask->pdc_disable);
 206                 prtd->params->dma_intr_handler = NULL;
 207         }
 208
 209         return 0;
 210 }
 211
 212 static int atmel_pcm_prepare(struct snd_pcm_substream *substream)
 213 {
 214         struct atmel_runtime_data *prtd = substream->runtime->private_data;
 215         struct atmel_pcm_dma_params *params = prtd->params;
 216
 217         ssc_writex(params->ssc->regs, SSC_IDR,
 218                    params->mask->ssc_endx | params->mask->ssc_endbuf);
 219         ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 220                    params->mask->pdc_disable);
 221         return 0;
 222 }
 223
 224 static int atmel_pcm_trigger(struct snd_pcm_substream *substream,
 225         int cmd)
 226 {
 227         struct snd_pcm_runtime *rtd = substream->runtime;
 228         struct atmel_runtime_data *prtd = rtd->private_data;
 229         struct atmel_pcm_dma_params *params = prtd->params;
 230         int ret = 0;
 231
 232         pr_debug("atmel-pcm:buffer_size = %ld,"
 233                 "dma_area = %p, dma_bytes = %u\n",
 234                 rtd->buffer_size, rtd->dma_area, rtd->dma_bytes);
 235
 236         switch (cmd) {
 237         case SNDRV_PCM_TRIGGER_START:
 238                 prtd->period_ptr = prtd->dma_buffer;
 239
 240                 ssc_writex(params->ssc->regs, params->pdc->xpr,
 241                            prtd->period_ptr);
 242                 ssc_writex(params->ssc->regs, params->pdc->xcr,
 243                            prtd->period_size / params->pdc_xfer_size);
 244
 245                 prtd->period_ptr += prtd->period_size;
 246                 ssc_writex(params->ssc->regs, params->pdc->xnpr,
 247                            prtd->period_ptr);
 248                 ssc_writex(params->ssc->regs, params->pdc->xncr,
 249                            prtd->period_size / params->pdc_xfer_size);
 250
 251                 pr_debug("atmel-pcm: trigger: "
 252                         "period_ptr=%lx, xpr=%u, "
 253                         "xcr=%u, xnpr=%u, xncr=%u\n",
 254                         (unsigned long)prtd->period_ptr,
 255                         ssc_readx(params->ssc->regs, params->pdc->xpr),
 256                         ssc_readx(params->ssc->regs, params->pdc->xcr),
 257                         ssc_readx(params->ssc->regs, params->pdc->xnpr),
 258                         ssc_readx(params->ssc->regs, params->pdc->xncr));
 259
 260                 ssc_writex(params->ssc->regs, SSC_IER,
 261                            params->mask->ssc_endx | params->mask->ssc_endbuf);
 262                 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
 263                            params->mask->pdc_enable);
 264
 265                 pr_debug("sr=%u imr=%u\n",
 266                         ssc_readx(params->ssc->regs, SSC_SR),
 267                         ssc_readx(params->ssc->regs, SSC_IER));
 268                 break;          /* SNDRV_PCM_TRIGGER_START */
 269
 270         case SNDRV_PCM_TRIGGER_STOP:
 271         case SNDRV_PCM_TRIGGER_SUSPEND:
 272         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 273                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 274                            params->mask->pdc_disable);
 275                 break;
 276
 277         case SNDRV_PCM_TRIGGER_RESUME:
 278         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 279                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 280                            params->mask->pdc_enable);
 281                 break;
 282
 283         default:
 284                 ret = -EINVAL;
 285         }
 286
 287         return ret;
 288 }
 289
 290 static snd_pcm_uframes_t atmel_pcm_pointer(
 291         struct snd_pcm_substream *substream)
 292 {
 293         struct snd_pcm_runtime *runtime = substream->runtime;
 294         struct atmel_runtime_data *prtd = runtime->private_data;
 295         struct atmel_pcm_dma_params *params = prtd->params;
 296         dma_addr_t ptr;
 297         snd_pcm_uframes_t x;
 298
 299         ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr);
 300         x = bytes_to_frames(runtime, ptr - prtd->dma_buffer);
 301
 302         if (x == runtime->buffer_size)
 303                 x = 0;
 304
 305         return x;
 306 }
 307
 308 static int atmel_pcm_open(struct snd_pcm_substream *substream)
 309 {
 310         struct snd_pcm_runtime *runtime = substream->runtime;
 311         struct atmel_runtime_data *prtd;
 312         int ret = 0;
 313
 314         snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware);
 315
 316         /* ensure that buffer size is a multiple of period size */
 317         ret = snd_pcm_hw_constraint_integer(runtime,
 318                                                 SNDRV_PCM_HW_PARAM_PERIODS);
 319         if (ret < 0)
 320                 goto out;
 321
 322         prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL);
 323         if (prtd == NULL) {
 324                 ret = -ENOMEM;
 325                 goto out;
 326         }
 327         runtime->private_data = prtd;
 328
 329  out:
 330         return ret;
 331 }
 332
 333 static int atmel_pcm_close(struct snd_pcm_substream *substream)
 334 {
 335         struct atmel_runtime_data *prtd = substream->runtime->private_data;
 336
 337         kfree(prtd);
 338         return 0;
 339 }
 340
 341 static int atmel_pcm_mmap(struct snd_pcm_substream *substream,
 342         struct vm_area_struct *vma)
 343 {
 344         return remap_pfn_range(vma, vma->vm_start,
 345                        substream->dma_buffer.addr >> PAGE_SHIFT,
 346                        vma->vm_end - vma->vm_start, vma->vm_page_prot);
 347 }
 348
 349 static struct snd_pcm_ops atmel_pcm_ops = {
 350         .open           = atmel_pcm_open,
 351         .close          = atmel_pcm_close,
 352         .ioctl          = snd_pcm_lib_ioctl,
 353         .hw_params      = atmel_pcm_hw_params,
 354         .hw_free        = atmel_pcm_hw_free,
 355         .prepare        = atmel_pcm_prepare,
 356         .trigger        = atmel_pcm_trigger,
 357         .pointer        = atmel_pcm_pointer,
 358         .mmap           = atmel_pcm_mmap,
 359 };
 360
 361
 362 /*--------------------------------------------------------------------------*\
 363  * ASoC platform driver
 364 \*--------------------------------------------------------------------------*/
 365 static u64 atmel_pcm_dmamask = 0xffffffff;
 366
 367 static int atmel_pcm_new(struct snd_card *card,
 368         struct snd_soc_dai *dai, struct snd_pcm *pcm)
 369 {
 370         int ret = 0;
 371
 372         if (!card->dev->dma_mask)
 373                 card->dev->dma_mask = &atmel_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 = atmel_pcm_preallocate_dma_buffer(pcm,
 379                         SNDRV_PCM_STREAM_PLAYBACK);
 380                 if (ret)
 381                         goto out;
 382         }
 383
 384         if (dai->capture.channels_min) {
 385                 pr_debug("at32-pcm:"
 386                                 "Allocating PCM capture DMA buffer\n");
 387                 ret = atmel_pcm_preallocate_dma_buffer(pcm,
 388                         SNDRV_PCM_STREAM_CAPTURE);
 389                 if (ret)
 390                         goto out;
 391         }
 392  out:
 393         return ret;
 394 }
 395
 396 static void atmel_pcm_free_dma_buffers(struct snd_pcm *pcm)
 397 {
 398         struct snd_pcm_substream *substream;
 399         struct snd_dma_buffer *buf;
 400         int stream;
 401
 402         for (stream = 0; stream < 2; stream++) {
 403                 substream = pcm->streams[stream].substream;
 404                 if (!substream)
 405                         continue;
 406
 407                 buf = &substream->dma_buffer;
 408                 if (!buf->area)
 409                         continue;
 410                 dma_free_coherent(pcm->card->dev, buf->bytes,
 411                                   buf->area, buf->addr);
 412                 buf->area = NULL;
 413         }
 414 }
 415
 416 #ifdef CONFIG_PM
 417 static int atmel_pcm_suspend(struct snd_soc_dai_link *dai_link)
 418 {
 419         struct snd_pcm *pcm = dai_link->pcm;
 420         struct snd_pcm_str *stream = &pcm->streams[0];
 421         struct snd_pcm_substream *substream = stream->substream;
 422         struct snd_pcm_runtime *runtime = substream->runtime;
 423         struct atmel_runtime_data *prtd;
 424         struct atmel_pcm_dma_params *params;
 425
 426         if (!runtime)
 427                 return 0;
 428
 429         prtd = runtime->private_data;
 430         params = prtd->params;
 431
 432         /* disable the PDC and save the PDC registers */
 433
 434         ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_disable);
 435
 436         prtd->pdc_xpr_save = ssc_readx(params->ssc->regs, params->pdc->xpr);
 437         prtd->pdc_xcr_save = ssc_readx(params->ssc->regs, params->pdc->xcr);
 438         prtd->pdc_xnpr_save = ssc_readx(params->ssc->regs, params->pdc->xnpr);
 439         prtd->pdc_xncr_save = ssc_readx(params->ssc->regs, params->pdc->xncr);
 440
 441         return 0;
 442 }
 443
 444 static int atmel_pcm_resume(struct snd_soc_dai_link *dai_link)
 445 {
 446         struct snd_pcm *pcm = dai_link->pcm;
 447         struct snd_pcm_str *stream = &pcm->streams[0];
 448         struct snd_pcm_substream *substream = stream->substream;
 449         struct snd_pcm_runtime *runtime = substream->runtime;
 450         struct atmel_runtime_data *prtd;
 451         struct atmel_pcm_dma_params *params;
 452
 453         if (!runtime)
 454                 return 0;
 455
 456         prtd = runtime->private_data;
 457         params = prtd->params;
 458
 459         /* restore the PDC registers and enable the PDC */
 460         ssc_writex(params->ssc->regs, params->pdc->xpr, prtd->pdc_xpr_save);
 461         ssc_writex(params->ssc->regs, params->pdc->xcr, prtd->pdc_xcr_save);
 462         ssc_writex(params->ssc->regs, params->pdc->xnpr, prtd->pdc_xnpr_save);
 463         ssc_writex(params->ssc->regs, params->pdc->xncr, prtd->pdc_xncr_save);
 464
 465         ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_enable);
 466         return 0;
 467 }
 468 #else
 469 #define atmel_pcm_suspend       NULL
 470 #define atmel_pcm_resume        NULL
 471 #endif
 472
 473 struct snd_soc_platform atmel_soc_platform = {
 474         .name           = "atmel-audio",
 475         .pcm_ops        = &atmel_pcm_ops,
 476         .pcm_new        = atmel_pcm_new,
 477         .pcm_free       = atmel_pcm_free_dma_buffers,
 478         .suspend        = atmel_pcm_suspend,
 479         .resume         = atmel_pcm_resume,
 480 };
 481 EXPORT_SYMBOL_GPL(atmel_soc_platform);
 482
 483 static int __init atmel_pcm_modinit(void)
 484 {
 485         return snd_soc_register_platform(&atmel_soc_platform);
 486 }
 487 module_init(atmel_pcm_modinit);
 488
 489 static void __exit atmel_pcm_modexit(void)
 490 {
 491         snd_soc_unregister_platform(&atmel_soc_platform);
 492 }
 493 module_exit(atmel_pcm_modexit);
 494
 495 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
 496 MODULE_DESCRIPTION("Atmel PCM module");
 497 MODULE_LICENSE("GPL");