sound/soc/atmel/atmel-pcm-pdc.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * atmel-pcm.c  --  ALSA PCM interface for the Atmel atmel SoC.
   4  *
   5  *  Copyright (C) 2005 SAN People
   6  *  Copyright (C) 2008 Atmel
   7  *
   8  * Authors: Sedji Gaouaou <sedji.gaouaou@atmel.com>
   9  *
  10  * Based on at91-pcm. by:
  11  * Frank Mandarino <fmandarino@endrelia.com>
  12  * Copyright 2006 Endrelia Technologies Inc.
  13  *
  14  * Based on pxa2xx-pcm.c by:
  15  *
  16  * Author:      Nicolas Pitre
  17  * Created:     Nov 30, 2004
  18  * Copyright:   (C) 2004 MontaVista Software, Inc.
  19  */
  20
  21 #include <linux/module.h>
  22 #include <linux/init.h>
  23 #include <linux/platform_device.h>
  24 #include <linux/slab.h>
  25 #include <linux/dma-mapping.h>
  26 #include <linux/atmel_pdc.h>
  27 #include <linux/atmel-ssc.h>
  28
  29 #include <sound/core.h>
  30 #include <sound/pcm.h>
  31 #include <sound/pcm_params.h>
  32 #include <sound/soc.h>
  33
  34 #include "atmel-pcm.h"
  35
  36
  37 static int atmel_pcm_preallocate_dma_buffer(struct snd_pcm *pcm,
  38         int stream)
  39 {
  40         struct snd_pcm_substream *substream = pcm->streams[stream].substream;
  41         struct snd_dma_buffer *buf = &substream->dma_buffer;
  42         size_t size = ATMEL_SSC_DMABUF_SIZE;
  43
  44         buf->dev.type = SNDRV_DMA_TYPE_DEV;
  45         buf->dev.dev = pcm->card->dev;
  46         buf->private_data = NULL;
  47         buf->area = dma_alloc_coherent(pcm->card->dev, size,
  48                         &buf->addr, GFP_KERNEL);
  49         pr_debug("atmel-pcm: alloc dma buffer: area=%p, addr=%p, size=%zu\n",
  50                         (void *)buf->area, (void *)(long)buf->addr, size);
  51
  52         if (!buf->area)
  53                 return -ENOMEM;
  54
  55         buf->bytes = size;
  56         return 0;
  57 }
  58
  59 static int atmel_pcm_mmap(struct snd_pcm_substream *substream,
  60         struct vm_area_struct *vma)
  61 {
  62         return remap_pfn_range(vma, vma->vm_start,
  63                        substream->dma_buffer.addr >> PAGE_SHIFT,
  64                        vma->vm_end - vma->vm_start, vma->vm_page_prot);
  65 }
  66
  67 static int atmel_pcm_new(struct snd_soc_pcm_runtime *rtd)
  68 {
  69         struct snd_card *card = rtd->card->snd_card;
  70         struct snd_pcm *pcm = rtd->pcm;
  71         int ret;
  72
  73         ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
  74         if (ret)
  75                 return ret;
  76
  77         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
  78                 pr_debug("atmel-pcm: allocating PCM playback DMA buffer\n");
  79                 ret = atmel_pcm_preallocate_dma_buffer(pcm,
  80                         SNDRV_PCM_STREAM_PLAYBACK);
  81                 if (ret)
  82                         goto out;
  83         }
  84
  85         if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
  86                 pr_debug("atmel-pcm: allocating PCM capture DMA buffer\n");
  87                 ret = atmel_pcm_preallocate_dma_buffer(pcm,
  88                         SNDRV_PCM_STREAM_CAPTURE);
  89                 if (ret)
  90                         goto out;
  91         }
  92  out:
  93         return ret;
  94 }
  95
  96 static void atmel_pcm_free(struct snd_pcm *pcm)
  97 {
  98         struct snd_pcm_substream *substream;
  99         struct snd_dma_buffer *buf;
 100         int stream;
 101
 102         for (stream = 0; stream < 2; stream++) {
 103                 substream = pcm->streams[stream].substream;
 104                 if (!substream)
 105                         continue;
 106
 107                 buf = &substream->dma_buffer;
 108                 if (!buf->area)
 109                         continue;
 110                 dma_free_coherent(pcm->card->dev, buf->bytes,
 111                                   buf->area, buf->addr);
 112                 buf->area = NULL;
 113         }
 114 }
 115
 116 /*--------------------------------------------------------------------------*\
 117  * Hardware definition
 118 \*--------------------------------------------------------------------------*/
 119 /* TODO: These values were taken from the AT91 platform driver, check
 120  *       them against real values for AT32
 121  */
 122 static const struct snd_pcm_hardware atmel_pcm_hardware = {
 123         .info                   = SNDRV_PCM_INFO_MMAP |
 124                                   SNDRV_PCM_INFO_MMAP_VALID |
 125                                   SNDRV_PCM_INFO_INTERLEAVED |
 126                                   SNDRV_PCM_INFO_PAUSE,
 127         .period_bytes_min       = 32,
 128         .period_bytes_max       = 8192,
 129         .periods_min            = 2,
 130         .periods_max            = 1024,
 131         .buffer_bytes_max       = ATMEL_SSC_DMABUF_SIZE,
 132 };
 133
 134
 135 /*--------------------------------------------------------------------------*\
 136  * Data types
 137 \*--------------------------------------------------------------------------*/
 138 struct atmel_runtime_data {
 139         struct atmel_pcm_dma_params *params;
 140         dma_addr_t dma_buffer;          /* physical address of dma buffer */
 141         dma_addr_t dma_buffer_end;      /* first address beyond DMA buffer */
 142         size_t period_size;
 143
 144         dma_addr_t period_ptr;          /* physical address of next period */
 145 };
 146
 147 /*--------------------------------------------------------------------------*\
 148  * ISR
 149 \*--------------------------------------------------------------------------*/
 150 static void atmel_pcm_dma_irq(u32 ssc_sr,
 151         struct snd_pcm_substream *substream)
 152 {
 153         struct atmel_runtime_data *prtd = substream->runtime->private_data;
 154         struct atmel_pcm_dma_params *params = prtd->params;
 155         static int count;
 156
 157         count++;
 158
 159         if (ssc_sr & params->mask->ssc_endbuf) {
 160                 pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x, count=%d)\n",
 161                                 substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 162                                 ? "underrun" : "overrun",
 163                                 params->name, ssc_sr, count);
 164
 165                 /* re-start the PDC */
 166                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 167                            params->mask->pdc_disable);
 168                 prtd->period_ptr += prtd->period_size;
 169                 if (prtd->period_ptr >= prtd->dma_buffer_end)
 170                         prtd->period_ptr = prtd->dma_buffer;
 171
 172                 ssc_writex(params->ssc->regs, params->pdc->xpr,
 173                            prtd->period_ptr);
 174                 ssc_writex(params->ssc->regs, params->pdc->xcr,
 175                            prtd->period_size / params->pdc_xfer_size);
 176                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 177                            params->mask->pdc_enable);
 178         }
 179
 180         if (ssc_sr & params->mask->ssc_endx) {
 181                 /* Load the PDC next pointer and counter registers */
 182                 prtd->period_ptr += prtd->period_size;
 183                 if (prtd->period_ptr >= prtd->dma_buffer_end)
 184                         prtd->period_ptr = prtd->dma_buffer;
 185
 186                 ssc_writex(params->ssc->regs, params->pdc->xnpr,
 187                            prtd->period_ptr);
 188                 ssc_writex(params->ssc->regs, params->pdc->xncr,
 189                            prtd->period_size / params->pdc_xfer_size);
 190         }
 191
 192         snd_pcm_period_elapsed(substream);
 193 }
 194
 195
 196 /*--------------------------------------------------------------------------*\
 197  * PCM operations
 198 \*--------------------------------------------------------------------------*/
 199 static int atmel_pcm_hw_params(struct snd_pcm_substream *substream,
 200         struct snd_pcm_hw_params *params)
 201 {
 202         struct snd_pcm_runtime *runtime = substream->runtime;
 203         struct atmel_runtime_data *prtd = runtime->private_data;
 204         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 205
 206         /* this may get called several times by oss emulation
 207          * with different params */
 208
 209         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 210         runtime->dma_bytes = params_buffer_bytes(params);
 211
 212         prtd->params = snd_soc_dai_get_dma_data(rtd->cpu_dai, substream);
 213         prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
 214
 215         prtd->dma_buffer = runtime->dma_addr;
 216         prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes;
 217         prtd->period_size = params_period_bytes(params);
 218
 219         pr_debug("atmel-pcm: "
 220                 "hw_params: DMA for %s initialized "
 221                 "(dma_bytes=%zu, period_size=%zu)\n",
 222                 prtd->params->name,
 223                 runtime->dma_bytes,
 224                 prtd->period_size);
 225         return 0;
 226 }
 227
 228 static int atmel_pcm_hw_free(struct snd_pcm_substream *substream)
 229 {
 230         struct atmel_runtime_data *prtd = substream->runtime->private_data;
 231         struct atmel_pcm_dma_params *params = prtd->params;
 232
 233         if (params != NULL) {
 234                 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
 235                            params->mask->pdc_disable);
 236                 prtd->params->dma_intr_handler = NULL;
 237         }
 238
 239         return 0;
 240 }
 241
 242 static int atmel_pcm_prepare(struct snd_pcm_substream *substream)
 243 {
 244         struct atmel_runtime_data *prtd = substream->runtime->private_data;
 245         struct atmel_pcm_dma_params *params = prtd->params;
 246
 247         ssc_writex(params->ssc->regs, SSC_IDR,
 248                    params->mask->ssc_endx | params->mask->ssc_endbuf);
 249         ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 250                    params->mask->pdc_disable);
 251         return 0;
 252 }
 253
 254 static int atmel_pcm_trigger(struct snd_pcm_substream *substream,
 255         int cmd)
 256 {
 257         struct snd_pcm_runtime *rtd = substream->runtime;
 258         struct atmel_runtime_data *prtd = rtd->private_data;
 259         struct atmel_pcm_dma_params *params = prtd->params;
 260         int ret = 0;
 261
 262         pr_debug("atmel-pcm:buffer_size = %ld,"
 263                 "dma_area = %p, dma_bytes = %zu\n",
 264                 rtd->buffer_size, rtd->dma_area, rtd->dma_bytes);
 265
 266         switch (cmd) {
 267         case SNDRV_PCM_TRIGGER_START:
 268                 prtd->period_ptr = prtd->dma_buffer;
 269
 270                 ssc_writex(params->ssc->regs, params->pdc->xpr,
 271                            prtd->period_ptr);
 272                 ssc_writex(params->ssc->regs, params->pdc->xcr,
 273                            prtd->period_size / params->pdc_xfer_size);
 274
 275                 prtd->period_ptr += prtd->period_size;
 276                 ssc_writex(params->ssc->regs, params->pdc->xnpr,
 277                            prtd->period_ptr);
 278                 ssc_writex(params->ssc->regs, params->pdc->xncr,
 279                            prtd->period_size / params->pdc_xfer_size);
 280
 281                 pr_debug("atmel-pcm: trigger: "
 282                         "period_ptr=%lx, xpr=%u, "
 283                         "xcr=%u, xnpr=%u, xncr=%u\n",
 284                         (unsigned long)prtd->period_ptr,
 285                         ssc_readx(params->ssc->regs, params->pdc->xpr),
 286                         ssc_readx(params->ssc->regs, params->pdc->xcr),
 287                         ssc_readx(params->ssc->regs, params->pdc->xnpr),
 288                         ssc_readx(params->ssc->regs, params->pdc->xncr));
 289
 290                 ssc_writex(params->ssc->regs, SSC_IER,
 291                            params->mask->ssc_endx | params->mask->ssc_endbuf);
 292                 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
 293                            params->mask->pdc_enable);
 294
 295                 pr_debug("sr=%u imr=%u\n",
 296                         ssc_readx(params->ssc->regs, SSC_SR),
 297                         ssc_readx(params->ssc->regs, SSC_IER));
 298                 break;          /* SNDRV_PCM_TRIGGER_START */
 299
 300         case SNDRV_PCM_TRIGGER_STOP:
 301         case SNDRV_PCM_TRIGGER_SUSPEND:
 302         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 303                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 304                            params->mask->pdc_disable);
 305                 break;
 306
 307         case SNDRV_PCM_TRIGGER_RESUME:
 308         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 309                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 310                            params->mask->pdc_enable);
 311                 break;
 312
 313         default:
 314                 ret = -EINVAL;
 315         }
 316
 317         return ret;
 318 }
 319
 320 static snd_pcm_uframes_t atmel_pcm_pointer(
 321         struct snd_pcm_substream *substream)
 322 {
 323         struct snd_pcm_runtime *runtime = substream->runtime;
 324         struct atmel_runtime_data *prtd = runtime->private_data;
 325         struct atmel_pcm_dma_params *params = prtd->params;
 326         dma_addr_t ptr;
 327         snd_pcm_uframes_t x;
 328
 329         ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr);
 330         x = bytes_to_frames(runtime, ptr - prtd->dma_buffer);
 331
 332         if (x == runtime->buffer_size)
 333                 x = 0;
 334
 335         return x;
 336 }
 337
 338 static int atmel_pcm_open(struct snd_pcm_substream *substream)
 339 {
 340         struct snd_pcm_runtime *runtime = substream->runtime;
 341         struct atmel_runtime_data *prtd;
 342         int ret = 0;
 343
 344         snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware);
 345
 346         /* ensure that buffer size is a multiple of period size */
 347         ret = snd_pcm_hw_constraint_integer(runtime,
 348                                                 SNDRV_PCM_HW_PARAM_PERIODS);
 349         if (ret < 0)
 350                 goto out;
 351
 352         prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL);
 353         if (prtd == NULL) {
 354                 ret = -ENOMEM;
 355                 goto out;
 356         }
 357         runtime->private_data = prtd;
 358
 359  out:
 360         return ret;
 361 }
 362
 363 static int atmel_pcm_close(struct snd_pcm_substream *substream)
 364 {
 365         struct atmel_runtime_data *prtd = substream->runtime->private_data;
 366
 367         kfree(prtd);
 368         return 0;
 369 }
 370
 371 static const struct snd_pcm_ops atmel_pcm_ops = {
 372         .open           = atmel_pcm_open,
 373         .close          = atmel_pcm_close,
 374         .ioctl          = snd_pcm_lib_ioctl,
 375         .hw_params      = atmel_pcm_hw_params,
 376         .hw_free        = atmel_pcm_hw_free,
 377         .prepare        = atmel_pcm_prepare,
 378         .trigger        = atmel_pcm_trigger,
 379         .pointer        = atmel_pcm_pointer,
 380         .mmap           = atmel_pcm_mmap,
 381 };
 382
 383 static struct snd_soc_component_driver atmel_soc_platform = {
 384         .ops            = &atmel_pcm_ops,
 385         .pcm_new        = atmel_pcm_new,
 386         .pcm_free       = atmel_pcm_free,
 387 };
 388
 389 int atmel_pcm_pdc_platform_register(struct device *dev)
 390 {
 391         return devm_snd_soc_register_component(dev, &atmel_soc_platform,
 392                                                NULL, 0);
 393 }
 394 EXPORT_SYMBOL(atmel_pcm_pdc_platform_register);
 395
 396 void atmel_pcm_pdc_platform_unregister(struct device *dev)
 397 {
 398 }
 399 EXPORT_SYMBOL(atmel_pcm_pdc_platform_unregister);
 400
 401 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
 402 MODULE_DESCRIPTION("Atmel PCM module");
 403 MODULE_LICENSE("GPL");