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_new(struct snd_soc_component *component,
  38                          struct snd_soc_pcm_runtime *rtd)
  39 {
  40         struct snd_card *card = rtd->card->snd_card;
  41         int ret;
  42
  43         ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
  44         if (ret)
  45                 return ret;
  46
  47         snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
  48                                        card->dev, ATMEL_SSC_DMABUF_SIZE,
  49                                        ATMEL_SSC_DMABUF_SIZE);
  50
  51         return 0;
  52 }
  53
  54 /*--------------------------------------------------------------------------*\
  55  * Hardware definition
  56 \*--------------------------------------------------------------------------*/
  57 /* TODO: These values were taken from the AT91 platform driver, check
  58  *       them against real values for AT32
  59  */
  60 static const struct snd_pcm_hardware atmel_pcm_hardware = {
  61         .info                   = SNDRV_PCM_INFO_MMAP |
  62                                   SNDRV_PCM_INFO_MMAP_VALID |
  63                                   SNDRV_PCM_INFO_INTERLEAVED |
  64                                   SNDRV_PCM_INFO_PAUSE,
  65         .period_bytes_min       = 32,
  66         .period_bytes_max       = 8192,
  67         .periods_min            = 2,
  68         .periods_max            = 1024,
  69         .buffer_bytes_max       = ATMEL_SSC_DMABUF_SIZE,
  70 };
  71
  72
  73 /*--------------------------------------------------------------------------*\
  74  * Data types
  75 \*--------------------------------------------------------------------------*/
  76 struct atmel_runtime_data {
  77         struct atmel_pcm_dma_params *params;
  78         dma_addr_t dma_buffer;          /* physical address of dma buffer */
  79         dma_addr_t dma_buffer_end;      /* first address beyond DMA buffer */
  80         size_t period_size;
  81
  82         dma_addr_t period_ptr;          /* physical address of next period */
  83 };
  84
  85 /*--------------------------------------------------------------------------*\
  86  * ISR
  87 \*--------------------------------------------------------------------------*/
  88 static void atmel_pcm_dma_irq(u32 ssc_sr,
  89         struct snd_pcm_substream *substream)
  90 {
  91         struct atmel_runtime_data *prtd = substream->runtime->private_data;
  92         struct atmel_pcm_dma_params *params = prtd->params;
  93         static int count;
  94
  95         count++;
  96
  97         if (ssc_sr & params->mask->ssc_endbuf) {
  98                 pr_warn("atmel-pcm: buffer %s on %s (SSC_SR=%#x, count=%d)\n",
  99                                 substream->stream == SNDRV_PCM_STREAM_PLAYBACK
 100                                 ? "underrun" : "overrun",
 101                                 params->name, ssc_sr, count);
 102
 103                 /* re-start the PDC */
 104                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 105                            params->mask->pdc_disable);
 106                 prtd->period_ptr += prtd->period_size;
 107                 if (prtd->period_ptr >= prtd->dma_buffer_end)
 108                         prtd->period_ptr = prtd->dma_buffer;
 109
 110                 ssc_writex(params->ssc->regs, params->pdc->xpr,
 111                            prtd->period_ptr);
 112                 ssc_writex(params->ssc->regs, params->pdc->xcr,
 113                            prtd->period_size / params->pdc_xfer_size);
 114                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 115                            params->mask->pdc_enable);
 116         }
 117
 118         if (ssc_sr & params->mask->ssc_endx) {
 119                 /* Load the PDC next pointer and counter registers */
 120                 prtd->period_ptr += prtd->period_size;
 121                 if (prtd->period_ptr >= prtd->dma_buffer_end)
 122                         prtd->period_ptr = prtd->dma_buffer;
 123
 124                 ssc_writex(params->ssc->regs, params->pdc->xnpr,
 125                            prtd->period_ptr);
 126                 ssc_writex(params->ssc->regs, params->pdc->xncr,
 127                            prtd->period_size / params->pdc_xfer_size);
 128         }
 129
 130         snd_pcm_period_elapsed(substream);
 131 }
 132
 133
 134 /*--------------------------------------------------------------------------*\
 135  * PCM operations
 136 \*--------------------------------------------------------------------------*/
 137 static int atmel_pcm_hw_params(struct snd_soc_component *component,
 138                                struct snd_pcm_substream *substream,
 139                                struct snd_pcm_hw_params *params)
 140 {
 141         struct snd_pcm_runtime *runtime = substream->runtime;
 142         struct atmel_runtime_data *prtd = runtime->private_data;
 143         struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 144
 145         /* this may get called several times by oss emulation
 146          * with different params */
 147
 148         prtd->params = snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(rtd, 0), substream);
 149         prtd->params->dma_intr_handler = atmel_pcm_dma_irq;
 150
 151         prtd->dma_buffer = runtime->dma_addr;
 152         prtd->dma_buffer_end = runtime->dma_addr + runtime->dma_bytes;
 153         prtd->period_size = params_period_bytes(params);
 154
 155         pr_debug("atmel-pcm: "
 156                 "hw_params: DMA for %s initialized "
 157                 "(dma_bytes=%zu, period_size=%zu)\n",
 158                 prtd->params->name,
 159                 runtime->dma_bytes,
 160                 prtd->period_size);
 161         return 0;
 162 }
 163
 164 static int atmel_pcm_hw_free(struct snd_soc_component *component,
 165                              struct snd_pcm_substream *substream)
 166 {
 167         struct atmel_runtime_data *prtd = substream->runtime->private_data;
 168         struct atmel_pcm_dma_params *params = prtd->params;
 169
 170         if (params != NULL) {
 171                 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
 172                            params->mask->pdc_disable);
 173                 prtd->params->dma_intr_handler = NULL;
 174         }
 175
 176         return 0;
 177 }
 178
 179 static int atmel_pcm_prepare(struct snd_soc_component *component,
 180                              struct snd_pcm_substream *substream)
 181 {
 182         struct atmel_runtime_data *prtd = substream->runtime->private_data;
 183         struct atmel_pcm_dma_params *params = prtd->params;
 184
 185         ssc_writex(params->ssc->regs, SSC_IDR,
 186                    params->mask->ssc_endx | params->mask->ssc_endbuf);
 187         ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 188                    params->mask->pdc_disable);
 189         return 0;
 190 }
 191
 192 static int atmel_pcm_trigger(struct snd_soc_component *component,
 193                              struct snd_pcm_substream *substream, int cmd)
 194 {
 195         struct snd_pcm_runtime *rtd = substream->runtime;
 196         struct atmel_runtime_data *prtd = rtd->private_data;
 197         struct atmel_pcm_dma_params *params = prtd->params;
 198         int ret = 0;
 199
 200         pr_debug("atmel-pcm:buffer_size = %ld,"
 201                 "dma_area = %p, dma_bytes = %zu\n",
 202                 rtd->buffer_size, rtd->dma_area, rtd->dma_bytes);
 203
 204         switch (cmd) {
 205         case SNDRV_PCM_TRIGGER_START:
 206                 prtd->period_ptr = prtd->dma_buffer;
 207
 208                 ssc_writex(params->ssc->regs, params->pdc->xpr,
 209                            prtd->period_ptr);
 210                 ssc_writex(params->ssc->regs, params->pdc->xcr,
 211                            prtd->period_size / params->pdc_xfer_size);
 212
 213                 prtd->period_ptr += prtd->period_size;
 214                 ssc_writex(params->ssc->regs, params->pdc->xnpr,
 215                            prtd->period_ptr);
 216                 ssc_writex(params->ssc->regs, params->pdc->xncr,
 217                            prtd->period_size / params->pdc_xfer_size);
 218
 219                 pr_debug("atmel-pcm: trigger: "
 220                         "period_ptr=%lx, xpr=%u, "
 221                         "xcr=%u, xnpr=%u, xncr=%u\n",
 222                         (unsigned long)prtd->period_ptr,
 223                         ssc_readx(params->ssc->regs, params->pdc->xpr),
 224                         ssc_readx(params->ssc->regs, params->pdc->xcr),
 225                         ssc_readx(params->ssc->regs, params->pdc->xnpr),
 226                         ssc_readx(params->ssc->regs, params->pdc->xncr));
 227
 228                 ssc_writex(params->ssc->regs, SSC_IER,
 229                            params->mask->ssc_endx | params->mask->ssc_endbuf);
 230                 ssc_writex(params->ssc->regs, SSC_PDC_PTCR,
 231                            params->mask->pdc_enable);
 232
 233                 pr_debug("sr=%u imr=%u\n",
 234                         ssc_readx(params->ssc->regs, SSC_SR),
 235                         ssc_readx(params->ssc->regs, SSC_IER));
 236                 break;          /* SNDRV_PCM_TRIGGER_START */
 237
 238         case SNDRV_PCM_TRIGGER_STOP:
 239         case SNDRV_PCM_TRIGGER_SUSPEND:
 240         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 241                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 242                            params->mask->pdc_disable);
 243                 break;
 244
 245         case SNDRV_PCM_TRIGGER_RESUME:
 246         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 247                 ssc_writex(params->ssc->regs, ATMEL_PDC_PTCR,
 248                            params->mask->pdc_enable);
 249                 break;
 250
 251         default:
 252                 ret = -EINVAL;
 253         }
 254
 255         return ret;
 256 }
 257
 258 static snd_pcm_uframes_t atmel_pcm_pointer(struct snd_soc_component *component,
 259                                            struct snd_pcm_substream *substream)
 260 {
 261         struct snd_pcm_runtime *runtime = substream->runtime;
 262         struct atmel_runtime_data *prtd = runtime->private_data;
 263         struct atmel_pcm_dma_params *params = prtd->params;
 264         dma_addr_t ptr;
 265         snd_pcm_uframes_t x;
 266
 267         ptr = (dma_addr_t) ssc_readx(params->ssc->regs, params->pdc->xpr);
 268         x = bytes_to_frames(runtime, ptr - prtd->dma_buffer);
 269
 270         if (x == runtime->buffer_size)
 271                 x = 0;
 272
 273         return x;
 274 }
 275
 276 static int atmel_pcm_open(struct snd_soc_component *component,
 277                           struct snd_pcm_substream *substream)
 278 {
 279         struct snd_pcm_runtime *runtime = substream->runtime;
 280         struct atmel_runtime_data *prtd;
 281         int ret = 0;
 282
 283         snd_soc_set_runtime_hwparams(substream, &atmel_pcm_hardware);
 284
 285         /* ensure that buffer size is a multiple of period size */
 286         ret = snd_pcm_hw_constraint_integer(runtime,
 287                                                 SNDRV_PCM_HW_PARAM_PERIODS);
 288         if (ret < 0)
 289                 goto out;
 290
 291         prtd = kzalloc(sizeof(struct atmel_runtime_data), GFP_KERNEL);
 292         if (prtd == NULL) {
 293                 ret = -ENOMEM;
 294                 goto out;
 295         }
 296         runtime->private_data = prtd;
 297
 298  out:
 299         return ret;
 300 }
 301
 302 static int atmel_pcm_close(struct snd_soc_component *component,
 303                            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 const struct snd_soc_component_driver atmel_soc_platform = {
 312         .open           = atmel_pcm_open,
 313         .close          = atmel_pcm_close,
 314         .hw_params      = atmel_pcm_hw_params,
 315         .hw_free        = atmel_pcm_hw_free,
 316         .prepare        = atmel_pcm_prepare,
 317         .trigger        = atmel_pcm_trigger,
 318         .pointer        = atmel_pcm_pointer,
 319         .pcm_construct  = atmel_pcm_new,
 320 };
 321
 322 int atmel_pcm_pdc_platform_register(struct device *dev)
 323 {
 324         return devm_snd_soc_register_component(dev, &atmel_soc_platform,
 325                                                NULL, 0);
 326 }
 327 EXPORT_SYMBOL(atmel_pcm_pdc_platform_register);
 328
 329 MODULE_AUTHOR("Sedji Gaouaou <sedji.gaouaou@atmel.com>");
 330 MODULE_DESCRIPTION("Atmel PCM module");
 331 MODULE_LICENSE("GPL");