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