linux/sound/soc/atmel/atmel-pcm.c
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   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 */
  56static 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\*--------------------------------------------------------------------------*/
  73struct 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\*--------------------------------------------------------------------------*/
  92static 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\*--------------------------------------------------------------------------*/
 119static 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\*--------------------------------------------------------------------------*/
 169static 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->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
 198static 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
 212static 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
 224static 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
 290static 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
 308static 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
 333static 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
 341static 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
 349static 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\*--------------------------------------------------------------------------*/
 365static u64 atmel_pcm_dmamask = 0xffffffff;
 366
 367static 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->driver->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->driver->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
 396static 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
 417static int atmel_pcm_suspend(struct snd_soc_dai *dai)
 418{
 419        struct snd_pcm_runtime *runtime = dai->runtime;
 420        struct atmel_runtime_data *prtd;
 421        struct atmel_pcm_dma_params *params;
 422
 423        if (!runtime)
 424                return 0;
 425
 426        prtd = runtime->private_data;
 427        params = prtd->params;
 428
 429        /* disable the PDC and save the PDC registers */
 430
 431        ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_disable);
 432
 433        prtd->pdc_xpr_save = ssc_readx(params->ssc->regs, params->pdc->xpr);
 434        prtd->pdc_xcr_save = ssc_readx(params->ssc->regs, params->pdc->xcr);
 435        prtd->pdc_xnpr_save = ssc_readx(params->ssc->regs, params->pdc->xnpr);
 436        prtd->pdc_xncr_save = ssc_readx(params->ssc->regs, params->pdc->xncr);
 437
 438        return 0;
 439}
 440
 441static int atmel_pcm_resume(struct snd_soc_dai *dai)
 442{
 443        struct snd_pcm_runtime *runtime = dai->runtime;
 444        struct atmel_runtime_data *prtd;
 445        struct atmel_pcm_dma_params *params;
 446
 447        if (!runtime)
 448                return 0;
 449
 450        prtd = runtime->private_data;
 451        params = prtd->params;
 452
 453        /* restore the PDC registers and enable the PDC */
 454        ssc_writex(params->ssc->regs, params->pdc->xpr, prtd->pdc_xpr_save);
 455        ssc_writex(params->ssc->regs, params->pdc->xcr, prtd->pdc_xcr_save);
 456        ssc_writex(params->ssc->regs, params->pdc->xnpr, prtd->pdc_xnpr_save);
 457        ssc_writex(params->ssc->regs, params->pdc->xncr, prtd->pdc_xncr_save);
 458
 459        ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_enable);
 460        return 0;
 461}
 462#else
 463#define atmel_pcm_suspend       NULL
 464#define atmel_pcm_resume        NULL
 465#endif
 466
 467static struct snd_soc_platform_driver atmel_soc_platform = {
 468        .ops            = &atmel_pcm_ops,
 469        .pcm_new        = atmel_pcm_new,
 470        .pcm_free       = atmel_pcm_free_dma_buffers,
 471        .suspend        = atmel_pcm_suspend,
 472        .resume         = atmel_pcm_resume,
 473};
 474
 475static int __devinit atmel_soc_platform_probe(struct platform_device *pdev)
 476{
 477        return snd_soc_register_platform(&pdev->dev, &atmel_soc_platform);
 478}
 479
 480static int __devexit atmel_soc_platform_remove(struct platform_device *pdev)
 481{
 482        snd_soc_unregister_platform(&pdev->dev);
 483        return 0;
 484}
 485
 486static struct platform_driver atmel_pcm_driver = {
 487        .driver = {
 488                        .name = "atmel-pcm-audio",
 489                        .owner = THIS_MODULE,
 490        },
 491
 492        .probe = atmel_soc_platform_probe,
 493        .remove = __devexit_p(atmel_soc_platform_remove),
 494};
 495
 496static int __init snd_atmel_pcm_init(void)
 497{
 498        return platform_driver_register(&atmel_pcm_driver);
 499}
 500module_init(snd_atmel_pcm_init);
 501
 502static void __exit snd_atmel_pcm_exit(void)
 503{
 504        platform_driver_unregister(&atmel_pcm_driver);
 505}
 506module_exit(snd_atmel_pcm_exit);
 507
 508MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
 509MODULE_DESCRIPTION("Atmel PCM module");
 510MODULE_LICENSE("GPL");
 511