LXR linux/sound/soc/atmel/atmel-pcm-pdc.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 */
  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       = ATMEL_SSC_DMABUF_SIZE,
  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 * ISR
  90\*--------------------------------------------------------------------------*/
  91static void atmel_pcm_dma_irq(u32 ssc_sr,
  92        struct snd_pcm_substream *substream)
  93{
  94        struct atmel_runtime_data *prtd = substream->runtime->private_data;
  95        struct atmel_pcm_dma_params *params = prtd->params;
  96        static int count;
  97
  98        count++;
  99
 100        if (ssc_sr & params->mask->ssc_endbuf) {
 101                pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x, count=%d)\n",
 102                                substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 103                                ? "underrun" : "overrun",
 104                                params->name, ssc_sr, count);
 105
 106                /* re-start the PDC */
 107                ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 108                           params->mask->pdc_disable);
 109                prtd->period_ptr += prtd->period_size;
 110                if (prtd->period_ptr >= prtd->dma_buffer_end)
 111                        prtd->period_ptr = prtd->dma_buffer;
 112
 113                ssc_writex(params->ssc->regs, params->pdc->xpr,
 114                           prtd->period_ptr);
 115                ssc_writex(params->ssc->regs, params->pdc->xcr,
 116                           prtd->period_size / params->pdc_xfer_size);
 117                ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 118                           params->mask->pdc_enable);
 119        }
 120
 121        if (ssc_sr & params->mask->ssc_endx) {
 122                /* Load the PDC next pointer and counter registers */
 123                prtd->period_ptr += prtd->period_size;
 124                if (prtd->period_ptr >= prtd->dma_buffer_end)
 125                        prtd->period_ptr = prtd->dma_buffer;
 126
 127                ssc_writex(params->ssc->regs, params->pdc->xnpr,
 128                           prtd->period_ptr);
 129                ssc_writex(params->ssc->regs, params->pdc->xncr,
 130                           prtd->period_size / params->pdc_xfer_size);
 131        }
 132
 133        snd_pcm_period_elapsed(substream);
 134}
 135
 136
 137/*--------------------------------------------------------------------------*\
 138 * PCM operations
 139\*--------------------------------------------------------------------------*/
 140static int atmel_pcm_hw_params(struct snd_pcm_substream *substream,
 141        struct snd_pcm_hw_params *params)
 142{
 143        struct snd_pcm_runtime *runtime = substream->runtime;
 144        struct atmel_runtime_data *prtd = runtime->private_data;
 145        struct snd_soc_pcm_runtime *rtd = substream->private_data;
 146
 147        /* this may get called several times by oss emulation
 148         * with different params */
 149
 150        snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 151        runtime->dma_bytes = params_buffer_bytes(params);
 152
 153        prtd->params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 154        prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
 155
 156        prtd->dma_buffer = runtime->dma_addr;
 157        prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes;
 158        prtd->period_size = params_period_bytes(params);
 159
 160        pr_debug("atmel-pcm: "
 161                "hw_params: DMA for %s initialized "
 162                "(dma_bytes=%zu, period_size=%zu)\n",
 163                prtd->params->name,
 164                runtime->dma_bytes,
 165                prtd->period_size);
 166        return 0;
 167}
 168
 169static int atmel_pcm_hw_free(struct snd_pcm_substream *substream)
 170{
 171        struct atmel_runtime_data *prtd = substream->runtime->private_data;
 172        struct atmel_pcm_dma_params *params = prtd->params;
 173
 174        if (params != NULL) {
 175                ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
 176                           params->mask->pdc_disable);
 177                prtd->params->dma_intr_handler = NULL;
 178        }
 179
 180        return 0;
 181}
 182
 183static int atmel_pcm_prepare(struct snd_pcm_substream *substream)
 184{
 185        struct atmel_runtime_data *prtd = substream->runtime->private_data;
 186        struct atmel_pcm_dma_params *params = prtd->params;
 187
 188        ssc_writex(params->ssc->regs, SSC_IDR,
 189                   params->mask->ssc_endx | params->mask->ssc_endbuf);
 190        ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 191                   params->mask->pdc_disable);
 192        return 0;
 193}
 194
 195static int atmel_pcm_trigger(struct snd_pcm_substream *substream,
 196        int cmd)
 197{
 198        struct snd_pcm_runtime *rtd = substream->runtime;
 199        struct atmel_runtime_data *prtd = rtd->private_data;
 200        struct atmel_pcm_dma_params *params = prtd->params;
 201        int ret = 0;
 202
 203        pr_debug("atmel-pcm:buffer_size = %ld,"
 204                "dma_area = %p, dma_bytes = %zu\n",
 205                rtd->buffer_size, rtd->dma_area, rtd->dma_bytes);
 206
 207        switch (cmd) {
 208        case SNDRV_PCM_TRIGGER_START:
 209                prtd->period_ptr = prtd->dma_buffer;
 210
 211                ssc_writex(params->ssc->regs, params->pdc->xpr,
 212                           prtd->period_ptr);
 213                ssc_writex(params->ssc->regs, params->pdc->xcr,
 214                           prtd->period_size / params->pdc_xfer_size);
 215
 216                prtd->period_ptr += prtd->period_size;
 217                ssc_writex(params->ssc->regs, params->pdc->xnpr,
 218                           prtd->period_ptr);
 219                ssc_writex(params->ssc->regs, params->pdc->xncr,
 220                           prtd->period_size / params->pdc_xfer_size);
 221
 222                pr_debug("atmel-pcm: trigger: "
 223                        "period_ptr=%lx, xpr=%u, "
 224                        "xcr=%u, xnpr=%u, xncr=%u\n",
 225                        (unsigned long)prtd->period_ptr,
 226                        ssc_readx(params->ssc->regs, params->pdc->xpr),
 227                        ssc_readx(params->ssc->regs, params->pdc->xcr),
 228                        ssc_readx(params->ssc->regs, params->pdc->xnpr),
 229                        ssc_readx(params->ssc->regs, params->pdc->xncr));
 230
 231                ssc_writex(params->ssc->regs, SSC_IER,
 232                           params->mask->ssc_endx | params->mask->ssc_endbuf);
 233                ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
 234                           params->mask->pdc_enable);
 235
 236                pr_debug("sr=%u imr=%u\n",
 237                        ssc_readx(params->ssc->regs, SSC_SR),
 238                        ssc_readx(params->ssc->regs, SSC_IER));
 239                break;          /* SNDRV_PCM_TRIGGER_START */
 240
 241        case SNDRV_PCM_TRIGGER_STOP:
 242        case SNDRV_PCM_TRIGGER_SUSPEND:
 243        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 244                ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 245                           params->mask->pdc_disable);
 246                break;
 247
 248        case SNDRV_PCM_TRIGGER_RESUME:
 249        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 250                ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 251                           params->mask->pdc_enable);
 252                break;
 253
 254        default:
 255                ret = -EINVAL;
 256        }
 257
 258        return ret;
 259}
 260
 261static snd_pcm_uframes_t atmel_pcm_pointer(
 262        struct snd_pcm_substream *substream)
 263{
 264        struct snd_pcm_runtime *runtime = substream->runtime;
 265        struct atmel_runtime_data *prtd = runtime->private_data;
 266        struct atmel_pcm_dma_params *params = prtd->params;
 267        dma_addr_t ptr;
 268        snd_pcm_uframes_t x;
 269
 270        ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr);
 271        x = bytes_to_frames(runtime, ptr - prtd->dma_buffer);
 272
 273        if (x == runtime->buffer_size)
 274                x = 0;
 275
 276        return x;
 277}
 278
 279static int atmel_pcm_open(struct snd_pcm_substream *substream)
 280{
 281        struct snd_pcm_runtime *runtime = substream->runtime;
 282        struct atmel_runtime_data *prtd;
 283        int ret = 0;
 284
 285        snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware);
 286
 287        /* ensure that buffer size is a multiple of period size */
 288        ret = snd_pcm_hw_constraint_integer(runtime,
 289                                                SNDRV_PCM_HW_PARAM_PERIODS);
 290        if (ret < 0)
 291                goto out;
 292
 293        prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL);
 294        if (prtd == NULL) {
 295                ret = -ENOMEM;
 296                goto out;
 297        }
 298        runtime->private_data = prtd;
 299
 300 out:
 301        return ret;
 302}
 303
 304static int atmel_pcm_close(struct snd_pcm_substream *substream)
 305{
 306        struct atmel_runtime_data *prtd = substream->runtime->private_data;
 307
 308        kfree(prtd);
 309        return 0;
 310}
 311
 312static struct snd_pcm_ops atmel_pcm_ops = {
 313        .open           = atmel_pcm_open,
 314        .close          = atmel_pcm_close,
 315        .ioctl          = snd_pcm_lib_ioctl,
 316        .hw_params      = atmel_pcm_hw_params,
 317        .hw_free        = atmel_pcm_hw_free,
 318        .prepare        = atmel_pcm_prepare,
 319        .trigger        = atmel_pcm_trigger,
 320        .pointer        = atmel_pcm_pointer,
 321        .mmap           = atmel_pcm_mmap,
 322};
 323
 324
 325/*--------------------------------------------------------------------------*\
 326 * ASoC platform driver
 327\*--------------------------------------------------------------------------*/
 328#ifdef CONFIG_PM
 329static int atmel_pcm_suspend(struct snd_soc_dai *dai)
 330{
 331        struct snd_pcm_runtime *runtime = dai->runtime;
 332        struct atmel_runtime_data *prtd;
 333        struct atmel_pcm_dma_params *params;
 334
 335        if (!runtime)
 336                return 0;
 337
 338        prtd = runtime->private_data;
 339        params = prtd->params;
 340
 341        /* disable the PDC and save the PDC registers */
 342
 343        ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_disable);
 344
 345        prtd->pdc_xpr_save = ssc_readx(params->ssc->regs, params->pdc->xpr);
 346        prtd->pdc_xcr_save = ssc_readx(params->ssc->regs, params->pdc->xcr);
 347        prtd->pdc_xnpr_save = ssc_readx(params->ssc->regs, params->pdc->xnpr);
 348        prtd->pdc_xncr_save = ssc_readx(params->ssc->regs, params->pdc->xncr);
 349
 350        return 0;
 351}
 352
 353static int atmel_pcm_resume(struct snd_soc_dai *dai)
 354{
 355        struct snd_pcm_runtime *runtime = dai->runtime;
 356        struct atmel_runtime_data *prtd;
 357        struct atmel_pcm_dma_params *params;
 358
 359        if (!runtime)
 360                return 0;
 361
 362        prtd = runtime->private_data;
 363        params = prtd->params;
 364
 365        /* restore the PDC registers and enable the PDC */
 366        ssc_writex(params->ssc->regs, params->pdc->xpr, prtd->pdc_xpr_save);
 367        ssc_writex(params->ssc->regs, params->pdc->xcr, prtd->pdc_xcr_save);
 368        ssc_writex(params->ssc->regs, params->pdc->xnpr, prtd->pdc_xnpr_save);
 369        ssc_writex(params->ssc->regs, params->pdc->xncr, prtd->pdc_xncr_save);
 370
 371        ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_enable);
 372        return 0;
 373}
 374#else
 375#define atmel_pcm_suspend       NULL
 376#define atmel_pcm_resume        NULL
 377#endif
 378
 379static struct snd_soc_platform_driver atmel_soc_platform = {
 380        .ops            = &atmel_pcm_ops,
 381        .pcm_new        = atmel_pcm_new,
 382        .pcm_free       = atmel_pcm_free,
 383        .suspend        = atmel_pcm_suspend,
 384        .resume         = atmel_pcm_resume,
 385};
 386
 387int atmel_pcm_pdc_platform_register(struct device *dev)
 388{
 389        return snd_soc_register_platform(dev, &atmel_soc_platform);
 390}
 391EXPORT_SYMBOL(atmel_pcm_pdc_platform_register);
 392
 393void atmel_pcm_pdc_platform_unregister(struct device *dev)
 394{
 395        snd_soc_unregister_platform(dev);
 396}
 397EXPORT_SYMBOL(atmel_pcm_pdc_platform_unregister);
 398
 399MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
 400MODULE_DESCRIPTION("Atmel PCM module");
 401MODULE_LICENSE("GPL");
 402