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         .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 \*--------------------------------------------------------------------------*/
  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  * ISR
  90 \*--------------------------------------------------------------------------*/
  91 static 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 \*--------------------------------------------------------------------------*/
 140 static 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
 169 static 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
 183 static 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
 195 static 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
 261 static 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
 279 static 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
 304 static 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
 312 static 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
 329 static 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
 353 static 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
 379 static 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
 387 int atmel_pcm_pdc_platform_register(struct device *dev)
 388 {
 389         return snd_soc_register_platform(dev, &atmel_soc_platform);
 390 }
 391 EXPORT_SYMBOL(atmel_pcm_pdc_platform_register);
 392
 393 void atmel_pcm_pdc_platform_unregister(struct device *dev)
 394 {
 395         snd_soc_unregister_platform(dev);
 396 }
 397 EXPORT_SYMBOL(atmel_pcm_pdc_platform_unregister);
 398
 399 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
 400 MODULE_DESCRIPTION("Atmel PCM module");
 401 MODULE_LICENSE("GPL");