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        .period_bytes_min       = 32,
  62        .period_bytes_max       = 8192,
  63        .periods_min            = 2,
  64        .periods_max            = 1024,
  65        .buffer_bytes_max       = ATMEL_SSC_DMABUF_SIZE,
  66};
  67
  68
  69/*--------------------------------------------------------------------------*\
  70 * Data types
  71\*--------------------------------------------------------------------------*/
  72struct atmel_runtime_data {
  73        struct atmel_pcm_dma_params *params;
  74        dma_addr_t dma_buffer;          /* physical address of dma buffer */
  75        dma_addr_t dma_buffer_end;      /* first address beyond DMA buffer */
  76        size_t period_size;
  77
  78        dma_addr_t period_ptr;          /* physical address of next period */
  79
  80        /* PDC register save */
  81        u32 pdc_xpr_save;
  82        u32 pdc_xcr_save;
  83        u32 pdc_xnpr_save;
  84        u32 pdc_xncr_save;
  85};
  86
  87/*--------------------------------------------------------------------------*\
  88 * ISR
  89\*--------------------------------------------------------------------------*/
  90static void atmel_pcm_dma_irq(u32 ssc_sr,
  91        struct snd_pcm_substream *substream)
  92{
  93        struct atmel_runtime_data *prtd = substream->runtime->private_data;
  94        struct atmel_pcm_dma_params *params = prtd->params;
  95        static int count;
  96
  97        count++;
  98
  99        if (ssc_sr & params->mask->ssc_endbuf) {
 100                pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x, count=%d)\n",
 101                                substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 102                                ? "underrun" : "overrun",
 103                                params->name, ssc_sr, count);
 104
 105                /* re-start the PDC */
 106                ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 107                           params->mask->pdc_disable);
 108                prtd->period_ptr += prtd->period_size;
 109                if (prtd->period_ptr >= prtd->dma_buffer_end)
 110                        prtd->period_ptr = prtd->dma_buffer;
 111
 112                ssc_writex(params->ssc->regs, params->pdc->xpr,
 113                           prtd->period_ptr);
 114                ssc_writex(params->ssc->regs, params->pdc->xcr,
 115                           prtd->period_size / params->pdc_xfer_size);
 116                ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 117                           params->mask->pdc_enable);
 118        }
 119
 120        if (ssc_sr & params->mask->ssc_endx) {
 121                /* Load the PDC next pointer and counter registers */
 122                prtd->period_ptr += prtd->period_size;
 123                if (prtd->period_ptr >= prtd->dma_buffer_end)
 124                        prtd->period_ptr = prtd->dma_buffer;
 125
 126                ssc_writex(params->ssc->regs, params->pdc->xnpr,
 127                           prtd->period_ptr);
 128                ssc_writex(params->ssc->regs, params->pdc->xncr,
 129                           prtd->period_size / params->pdc_xfer_size);
 130        }
 131
 132        snd_pcm_period_elapsed(substream);
 133}
 134
 135
 136/*--------------------------------------------------------------------------*\
 137 * PCM operations
 138\*--------------------------------------------------------------------------*/
 139static int atmel_pcm_hw_params(struct snd_pcm_substream *substream,
 140        struct snd_pcm_hw_params *params)
 141{
 142        struct snd_pcm_runtime *runtime = substream->runtime;
 143        struct atmel_runtime_data *prtd = runtime->private_data;
 144        struct snd_soc_pcm_runtime *rtd = substream->private_data;
 145
 146        /* this may get called several times by oss emulation
 147         * with different params */
 148
 149        snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 150        runtime->dma_bytes = params_buffer_bytes(params);
 151
 152        prtd->params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 153        prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
 154
 155        prtd->dma_buffer = runtime->dma_addr;
 156        prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes;
 157        prtd->period_size = params_period_bytes(params);
 158
 159        pr_debug("atmel-pcm: "
 160                "hw_params: DMA for %s initialized "
 161                "(dma_bytes=%zu, period_size=%zu)\n",
 162                prtd->params->name,
 163                runtime->dma_bytes,
 164                prtd->period_size);
 165        return 0;
 166}
 167
 168static int atmel_pcm_hw_free(struct snd_pcm_substream *substream)
 169{
 170        struct atmel_runtime_data *prtd = substream->runtime->private_data;
 171        struct atmel_pcm_dma_params *params = prtd->params;
 172
 173        if (params != NULL) {
 174                ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
 175                           params->mask->pdc_disable);
 176                prtd->params->dma_intr_handler = NULL;
 177        }
 178
 179        return 0;
 180}
 181
 182static int atmel_pcm_prepare(struct snd_pcm_substream *substream)
 183{
 184        struct atmel_runtime_data *prtd = substream->runtime->private_data;
 185        struct atmel_pcm_dma_params *params = prtd->params;
 186
 187        ssc_writex(params->ssc->regs, SSC_IDR,
 188                   params->mask->ssc_endx | params->mask->ssc_endbuf);
 189        ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 190                   params->mask->pdc_disable);
 191        return 0;
 192}
 193
 194static int atmel_pcm_trigger(struct snd_pcm_substream *substream,
 195        int cmd)
 196{
 197        struct snd_pcm_runtime *rtd = substream->runtime;
 198        struct atmel_runtime_data *prtd = rtd->private_data;
 199        struct atmel_pcm_dma_params *params = prtd->params;
 200        int ret = 0;
 201
 202        pr_debug("atmel-pcm:buffer_size = %ld,"
 203                "dma_area = %p, dma_bytes = %zu\n",
 204                rtd->buffer_size, rtd->dma_area, rtd->dma_bytes);
 205
 206        switch (cmd) {
 207        case SNDRV_PCM_TRIGGER_START:
 208                prtd->period_ptr = prtd->dma_buffer;
 209
 210                ssc_writex(params->ssc->regs, params->pdc->xpr,
 211                           prtd->period_ptr);
 212                ssc_writex(params->ssc->regs, params->pdc->xcr,
 213                           prtd->period_size / params->pdc_xfer_size);
 214
 215                prtd->period_ptr += prtd->period_size;
 216                ssc_writex(params->ssc->regs, params->pdc->xnpr,
 217                           prtd->period_ptr);
 218                ssc_writex(params->ssc->regs, params->pdc->xncr,
 219                           prtd->period_size / params->pdc_xfer_size);
 220
 221                pr_debug("atmel-pcm: trigger: "
 222                        "period_ptr=%lx, xpr=%u, "
 223                        "xcr=%u, xnpr=%u, xncr=%u\n",
 224                        (unsigned long)prtd->period_ptr,
 225                        ssc_readx(params->ssc->regs, params->pdc->xpr),
 226                        ssc_readx(params->ssc->regs, params->pdc->xcr),
 227                        ssc_readx(params->ssc->regs, params->pdc->xnpr),
 228                        ssc_readx(params->ssc->regs, params->pdc->xncr));
 229
 230                ssc_writex(params->ssc->regs, SSC_IER,
 231                           params->mask->ssc_endx | params->mask->ssc_endbuf);
 232                ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
 233                           params->mask->pdc_enable);
 234
 235                pr_debug("sr=%u imr=%u\n",
 236                        ssc_readx(params->ssc->regs, SSC_SR),
 237                        ssc_readx(params->ssc->regs, SSC_IER));
 238                break;          /* SNDRV_PCM_TRIGGER_START */
 239
 240        case SNDRV_PCM_TRIGGER_STOP:
 241        case SNDRV_PCM_TRIGGER_SUSPEND:
 242        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 243                ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 244                           params->mask->pdc_disable);
 245                break;
 246
 247        case SNDRV_PCM_TRIGGER_RESUME:
 248        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 249                ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 250                           params->mask->pdc_enable);
 251                break;
 252
 253        default:
 254                ret = -EINVAL;
 255        }
 256
 257        return ret;
 258}
 259
 260static snd_pcm_uframes_t atmel_pcm_pointer(
 261        struct snd_pcm_substream *substream)
 262{
 263        struct snd_pcm_runtime *runtime = substream->runtime;
 264        struct atmel_runtime_data *prtd = runtime->private_data;
 265        struct atmel_pcm_dma_params *params = prtd->params;
 266        dma_addr_t ptr;
 267        snd_pcm_uframes_t x;
 268
 269        ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr);
 270        x = bytes_to_frames(runtime, ptr - prtd->dma_buffer);
 271
 272        if (x == runtime->buffer_size)
 273                x = 0;
 274
 275        return x;
 276}
 277
 278static int atmel_pcm_open(struct snd_pcm_substream *substream)
 279{
 280        struct snd_pcm_runtime *runtime = substream->runtime;
 281        struct atmel_runtime_data *prtd;
 282        int ret = 0;
 283
 284        snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware);
 285
 286        /* ensure that buffer size is a multiple of period size */
 287        ret = snd_pcm_hw_constraint_integer(runtime,
 288                                                SNDRV_PCM_HW_PARAM_PERIODS);
 289        if (ret < 0)
 290                goto out;
 291
 292        prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL);
 293        if (prtd == NULL) {
 294                ret = -ENOMEM;
 295                goto out;
 296        }
 297        runtime->private_data = prtd;
 298
 299 out:
 300        return ret;
 301}
 302
 303static int atmel_pcm_close(struct snd_pcm_substream *substream)
 304{
 305        struct atmel_runtime_data *prtd = substream->runtime->private_data;
 306
 307        kfree(prtd);
 308        return 0;
 309}
 310
 311static struct snd_pcm_ops atmel_pcm_ops = {
 312        .open           = atmel_pcm_open,
 313        .close          = atmel_pcm_close,
 314        .ioctl          = snd_pcm_lib_ioctl,
 315        .hw_params      = atmel_pcm_hw_params,
 316        .hw_free        = atmel_pcm_hw_free,
 317        .prepare        = atmel_pcm_prepare,
 318        .trigger        = atmel_pcm_trigger,
 319        .pointer        = atmel_pcm_pointer,
 320        .mmap           = atmel_pcm_mmap,
 321};
 322
 323
 324/*--------------------------------------------------------------------------*\
 325 * ASoC platform driver
 326\*--------------------------------------------------------------------------*/
 327#ifdef CONFIG_PM
 328static int atmel_pcm_suspend(struct snd_soc_dai *dai)
 329{
 330        struct snd_pcm_runtime *runtime = dai->runtime;
 331        struct atmel_runtime_data *prtd;
 332        struct atmel_pcm_dma_params *params;
 333
 334        if (!runtime)
 335                return 0;
 336
 337        prtd = runtime->private_data;
 338        params = prtd->params;
 339
 340        /* disable the PDC and save the PDC registers */
 341
 342        ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_disable);
 343
 344        prtd->pdc_xpr_save = ssc_readx(params->ssc->regs, params->pdc->xpr);
 345        prtd->pdc_xcr_save = ssc_readx(params->ssc->regs, params->pdc->xcr);
 346        prtd->pdc_xnpr_save = ssc_readx(params->ssc->regs, params->pdc->xnpr);
 347        prtd->pdc_xncr_save = ssc_readx(params->ssc->regs, params->pdc->xncr);
 348
 349        return 0;
 350}
 351
 352static int atmel_pcm_resume(struct snd_soc_dai *dai)
 353{
 354        struct snd_pcm_runtime *runtime = dai->runtime;
 355        struct atmel_runtime_data *prtd;
 356        struct atmel_pcm_dma_params *params;
 357
 358        if (!runtime)
 359                return 0;
 360
 361        prtd = runtime->private_data;
 362        params = prtd->params;
 363
 364        /* restore the PDC registers and enable the PDC */
 365        ssc_writex(params->ssc->regs, params->pdc->xpr, prtd->pdc_xpr_save);
 366        ssc_writex(params->ssc->regs, params->pdc->xcr, prtd->pdc_xcr_save);
 367        ssc_writex(params->ssc->regs, params->pdc->xnpr, prtd->pdc_xnpr_save);
 368        ssc_writex(params->ssc->regs, params->pdc->xncr, prtd->pdc_xncr_save);
 369
 370        ssc_writel(params->ssc->regs, PDC_PTCR, params->mask->pdc_enable);
 371        return 0;
 372}
 373#else
 374#define atmel_pcm_suspend       NULL
 375#define atmel_pcm_resume        NULL
 376#endif
 377
 378static struct snd_soc_platform_driver atmel_soc_platform = {
 379        .ops            = &atmel_pcm_ops,
 380        .pcm_new        = atmel_pcm_new,
 381        .pcm_free       = atmel_pcm_free,
 382        .suspend        = atmel_pcm_suspend,
 383        .resume         = atmel_pcm_resume,
 384};
 385
 386int atmel_pcm_pdc_platform_register(struct device *dev)
 387{
 388        return snd_soc_register_platform(dev, &atmel_soc_platform);
 389}
 390EXPORT_SYMBOL(atmel_pcm_pdc_platform_register);
 391
 392void atmel_pcm_pdc_platform_unregister(struct device *dev)
 393{
 394        snd_soc_unregister_platform(dev);
 395}
 396EXPORT_SYMBOL(atmel_pcm_pdc_platform_unregister);
 397
 398MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
 399MODULE_DESCRIPTION("Atmel PCM module");
 400MODULE_LICENSE("GPL");
 401