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  */
  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         .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 \*--------------------------------------------------------------------------*/
  72 struct 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 \*--------------------------------------------------------------------------*/
  90 static 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 \*--------------------------------------------------------------------------*/
 139 static 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
 168 static 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
 182 static 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
 194 static 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
 260 static 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
 278 static 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
 303 static 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
 311 static 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
 328 static 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
 352 static 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
 378 static 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
 386 int atmel_pcm_pdc_platform_register(struct device *dev)
 387 {
 388         return snd_soc_register_platform(dev, &atmel_soc_platform);
 389 }
 390 EXPORT_SYMBOL(atmel_pcm_pdc_platform_register);
 391
 392 void atmel_pcm_pdc_platform_unregister(struct device *dev)
 393 {
 394         snd_soc_unregister_platform(dev);
 395 }
 396 EXPORT_SYMBOL(atmel_pcm_pdc_platform_unregister);
 397
 398 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
 399 MODULE_DESCRIPTION("Atmel PCM module");
 400 MODULE_LICENSE("GPL");