sound/soc/fsl/mpc5200_dma.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 //
   3 // Freescale MPC5200 PSC DMA
   4 // ALSA SoC Platform driver
   5 //
   6 // Copyright (C) 2008 Secret Lab Technologies Ltd.
   7 // Copyright (C) 2009 Jon Smirl, Digispeaker
   8
   9 #include <linux/module.h>
  10 #include <linux/of_device.h>
  11 #include <linux/dma-mapping.h>
  12 #include <linux/slab.h>
  13 #include <linux/of_address.h>
  14 #include <linux/of_irq.h>
  15 #include <linux/of_platform.h>
  16
  17 #include <sound/soc.h>
  18
  19 #include <linux/fsl/bestcomm/bestcomm.h>
  20 #include <linux/fsl/bestcomm/gen_bd.h>
  21 #include <asm/mpc52xx_psc.h>
  22
  23 #include "mpc5200_dma.h"
  24
  25 #define DRV_NAME "mpc5200_dma"
  26
  27 /*
  28  * Interrupt handlers
  29  */
  30 static irqreturn_t psc_dma_status_irq(int irq, void *_psc_dma)
  31 {
  32         struct psc_dma *psc_dma = _psc_dma;
  33         struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
  34         u16 isr;
  35
  36         isr = in_be16(&regs->mpc52xx_psc_isr);
  37
  38         /* Playback underrun error */
  39         if (psc_dma->playback.active && (isr & MPC52xx_PSC_IMR_TXEMP))
  40                 psc_dma->stats.underrun_count++;
  41
  42         /* Capture overrun error */
  43         if (psc_dma->capture.active && (isr & MPC52xx_PSC_IMR_ORERR))
  44                 psc_dma->stats.overrun_count++;
  45
  46         out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
  47
  48         return IRQ_HANDLED;
  49 }
  50
  51 /**
  52  * psc_dma_bcom_enqueue_next_buffer - Enqueue another audio buffer
  53  * @s: pointer to stream private data structure
  54  *
  55  * Enqueues another audio period buffer into the bestcomm queue.
  56  *
  57  * Note: The routine must only be called when there is space available in
  58  * the queue.  Otherwise the enqueue will fail and the audio ring buffer
  59  * will get out of sync
  60  */
  61 static void psc_dma_bcom_enqueue_next_buffer(struct psc_dma_stream *s)
  62 {
  63         struct bcom_bd *bd;
  64
  65         /* Prepare and enqueue the next buffer descriptor */
  66         bd = bcom_prepare_next_buffer(s->bcom_task);
  67         bd->status = s->period_bytes;
  68         bd->data[0] = s->runtime->dma_addr + (s->period_next * s->period_bytes);
  69         bcom_submit_next_buffer(s->bcom_task, NULL);
  70
  71         /* Update for next period */
  72         s->period_next = (s->period_next + 1) % s->runtime->periods;
  73 }
  74
  75 /* Bestcomm DMA irq handler */
  76 static irqreturn_t psc_dma_bcom_irq(int irq, void *_psc_dma_stream)
  77 {
  78         struct psc_dma_stream *s = _psc_dma_stream;
  79
  80         spin_lock(&s->psc_dma->lock);
  81         /* For each finished period, dequeue the completed period buffer
  82          * and enqueue a new one in it's place. */
  83         while (bcom_buffer_done(s->bcom_task)) {
  84                 bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
  85
  86                 s->period_current = (s->period_current+1) % s->runtime->periods;
  87                 s->period_count++;
  88
  89                 psc_dma_bcom_enqueue_next_buffer(s);
  90         }
  91         spin_unlock(&s->psc_dma->lock);
  92
  93         /* If the stream is active, then also inform the PCM middle layer
  94          * of the period finished event. */
  95         if (s->active)
  96                 snd_pcm_period_elapsed(s->stream);
  97
  98         return IRQ_HANDLED;
  99 }
 100
 101 static int psc_dma_hw_free(struct snd_soc_component *component,
 102                            struct snd_pcm_substream *substream)
 103 {
 104         snd_pcm_set_runtime_buffer(substream, NULL);
 105         return 0;
 106 }
 107
 108 /**
 109  * psc_dma_trigger: start and stop the DMA transfer.
 110  *
 111  * This function is called by ALSA to start, stop, pause, and resume the DMA
 112  * transfer of data.
 113  */
 114 static int psc_dma_trigger(struct snd_soc_component *component,
 115                            struct snd_pcm_substream *substream, int cmd)
 116 {
 117         struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 118         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
 119         struct snd_pcm_runtime *runtime = substream->runtime;
 120         struct psc_dma_stream *s = to_psc_dma_stream(substream, psc_dma);
 121         struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
 122         u16 imr;
 123         unsigned long flags;
 124         int i;
 125
 126         switch (cmd) {
 127         case SNDRV_PCM_TRIGGER_START:
 128                 dev_dbg(psc_dma->dev, "START: stream=%i fbits=%u ps=%u #p=%u\n",
 129                         substream->pstr->stream, runtime->frame_bits,
 130                         (int)runtime->period_size, runtime->periods);
 131                 s->period_bytes = frames_to_bytes(runtime,
 132                                                   runtime->period_size);
 133                 s->period_next = 0;
 134                 s->period_current = 0;
 135                 s->active = 1;
 136                 s->period_count = 0;
 137                 s->runtime = runtime;
 138
 139                 /* Fill up the bestcomm bd queue and enable DMA.
 140                  * This will begin filling the PSC's fifo.
 141                  */
 142                 spin_lock_irqsave(&psc_dma->lock, flags);
 143
 144                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 145                         bcom_gen_bd_rx_reset(s->bcom_task);
 146                 else
 147                         bcom_gen_bd_tx_reset(s->bcom_task);
 148
 149                 for (i = 0; i < runtime->periods; i++)
 150                         if (!bcom_queue_full(s->bcom_task))
 151                                 psc_dma_bcom_enqueue_next_buffer(s);
 152
 153                 bcom_enable(s->bcom_task);
 154                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 155
 156                 out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
 157
 158                 break;
 159
 160         case SNDRV_PCM_TRIGGER_STOP:
 161                 dev_dbg(psc_dma->dev, "STOP: stream=%i periods_count=%i\n",
 162                         substream->pstr->stream, s->period_count);
 163                 s->active = 0;
 164
 165                 spin_lock_irqsave(&psc_dma->lock, flags);
 166                 bcom_disable(s->bcom_task);
 167                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 168                         bcom_gen_bd_rx_reset(s->bcom_task);
 169                 else
 170                         bcom_gen_bd_tx_reset(s->bcom_task);
 171                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 172
 173                 break;
 174
 175         default:
 176                 dev_dbg(psc_dma->dev, "unhandled trigger: stream=%i cmd=%i\n",
 177                         substream->pstr->stream, cmd);
 178                 return -EINVAL;
 179         }
 180
 181         /* Update interrupt enable settings */
 182         imr = 0;
 183         if (psc_dma->playback.active)
 184                 imr |= MPC52xx_PSC_IMR_TXEMP;
 185         if (psc_dma->capture.active)
 186                 imr |= MPC52xx_PSC_IMR_ORERR;
 187         out_be16(&regs->isr_imr.imr, psc_dma->imr | imr);
 188
 189         return 0;
 190 }
 191
 192
 193 /* ---------------------------------------------------------------------
 194  * The PSC DMA 'ASoC platform' driver
 195  *
 196  * Can be referenced by an 'ASoC machine' driver
 197  * This driver only deals with the audio bus; it doesn't have any
 198  * interaction with the attached codec
 199  */
 200
 201 static const struct snd_pcm_hardware psc_dma_hardware = {
 202         .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
 203                 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
 204                 SNDRV_PCM_INFO_BATCH,
 205         .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE |
 206                 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE,
 207         .period_bytes_max       = 1024 * 1024,
 208         .period_bytes_min       = 32,
 209         .periods_min            = 2,
 210         .periods_max            = 256,
 211         .buffer_bytes_max       = 2 * 1024 * 1024,
 212         .fifo_size              = 512,
 213 };
 214
 215 static int psc_dma_open(struct snd_soc_component *component,
 216                         struct snd_pcm_substream *substream)
 217 {
 218         struct snd_pcm_runtime *runtime = substream->runtime;
 219         struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 220         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
 221         struct psc_dma_stream *s;
 222         int rc;
 223
 224         dev_dbg(psc_dma->dev, "psc_dma_open(substream=%p)\n", substream);
 225
 226         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 227                 s = &psc_dma->capture;
 228         else
 229                 s = &psc_dma->playback;
 230
 231         snd_soc_set_runtime_hwparams(substream, &psc_dma_hardware);
 232
 233         rc = snd_pcm_hw_constraint_integer(runtime,
 234                 SNDRV_PCM_HW_PARAM_PERIODS);
 235         if (rc < 0) {
 236                 dev_err(substream->pcm->card->dev, "invalid buffer size\n");
 237                 return rc;
 238         }
 239
 240         s->stream = substream;
 241         return 0;
 242 }
 243
 244 static int psc_dma_close(struct snd_soc_component *component,
 245                          struct snd_pcm_substream *substream)
 246 {
 247         struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 248         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
 249         struct psc_dma_stream *s;
 250
 251         dev_dbg(psc_dma->dev, "psc_dma_close(substream=%p)\n", substream);
 252
 253         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 254                 s = &psc_dma->capture;
 255         else
 256                 s = &psc_dma->playback;
 257
 258         if (!psc_dma->playback.active &&
 259             !psc_dma->capture.active) {
 260
 261                 /* Disable all interrupts and reset the PSC */
 262                 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr);
 263                 out_8(&psc_dma->psc_regs->command, 4 << 4); /* reset error */
 264         }
 265         s->stream = NULL;
 266         return 0;
 267 }
 268
 269 static snd_pcm_uframes_t
 270 psc_dma_pointer(struct snd_soc_component *component,
 271                 struct snd_pcm_substream *substream)
 272 {
 273         struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 274         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
 275         struct psc_dma_stream *s;
 276         dma_addr_t count;
 277
 278         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 279                 s = &psc_dma->capture;
 280         else
 281                 s = &psc_dma->playback;
 282
 283         count = s->period_current * s->period_bytes;
 284
 285         return bytes_to_frames(substream->runtime, count);
 286 }
 287
 288 static int psc_dma_hw_params(struct snd_soc_component *component,
 289                              struct snd_pcm_substream *substream,
 290                              struct snd_pcm_hw_params *params)
 291 {
 292         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 293
 294         return 0;
 295 }
 296
 297 static int psc_dma_new(struct snd_soc_component *component,
 298                        struct snd_soc_pcm_runtime *rtd)
 299 {
 300         struct snd_card *card = rtd->card->snd_card;
 301         struct snd_soc_dai *dai = asoc_rtd_to_cpu(rtd, 0);
 302         struct snd_pcm *pcm = rtd->pcm;
 303         size_t size = psc_dma_hardware.buffer_bytes_max;
 304         int rc;
 305
 306         dev_dbg(component->dev, "psc_dma_new(card=%p, dai=%p, pcm=%p)\n",
 307                 card, dai, pcm);
 308
 309         rc = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
 310         if (rc)
 311                 return rc;
 312
 313         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 314                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 315                                 size, &pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer);
 316                 if (rc)
 317                         goto playback_alloc_err;
 318         }
 319
 320         if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
 321                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 322                                 size, &pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream->dma_buffer);
 323                 if (rc)
 324                         goto capture_alloc_err;
 325         }
 326
 327         return 0;
 328
 329  capture_alloc_err:
 330         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
 331                 snd_dma_free_pages(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer);
 332
 333  playback_alloc_err:
 334         dev_err(card->dev, "Cannot allocate buffer(s)\n");
 335
 336         return -ENOMEM;
 337 }
 338
 339 static void psc_dma_free(struct snd_soc_component *component,
 340                          struct snd_pcm *pcm)
 341 {
 342         struct snd_soc_pcm_runtime *rtd = pcm->private_data;
 343         struct snd_pcm_substream *substream;
 344         int stream;
 345
 346         dev_dbg(component->dev, "psc_dma_free(pcm=%p)\n", pcm);
 347
 348         for (stream = 0; stream < 2; stream++) {
 349                 substream = pcm->streams[stream].substream;
 350                 if (substream) {
 351                         snd_dma_free_pages(&substream->dma_buffer);
 352                         substream->dma_buffer.area = NULL;
 353                         substream->dma_buffer.addr = 0;
 354                 }
 355         }
 356 }
 357
 358 static const struct snd_soc_component_driver mpc5200_audio_dma_component = {
 359         .name           = DRV_NAME,
 360         .open           = psc_dma_open,
 361         .close          = psc_dma_close,
 362         .hw_free        = psc_dma_hw_free,
 363         .pointer        = psc_dma_pointer,
 364         .trigger        = psc_dma_trigger,
 365         .hw_params      = psc_dma_hw_params,
 366         .pcm_construct  = psc_dma_new,
 367         .pcm_destruct   = psc_dma_free,
 368 };
 369
 370 int mpc5200_audio_dma_create(struct platform_device *op)
 371 {
 372         phys_addr_t fifo;
 373         struct psc_dma *psc_dma;
 374         struct resource res;
 375         int size, irq, rc;
 376         const __be32 *prop;
 377         void __iomem *regs;
 378         int ret;
 379
 380         /* Fetch the registers and IRQ of the PSC */
 381         irq = irq_of_parse_and_map(op->dev.of_node, 0);
 382         if (of_address_to_resource(op->dev.of_node, 0, &res)) {
 383                 dev_err(&op->dev, "Missing reg property\n");
 384                 return -ENODEV;
 385         }
 386         regs = ioremap(res.start, resource_size(&res));
 387         if (!regs) {
 388                 dev_err(&op->dev, "Could not map registers\n");
 389                 return -ENODEV;
 390         }
 391
 392         /* Allocate and initialize the driver private data */
 393         psc_dma = kzalloc(sizeof *psc_dma, GFP_KERNEL);
 394         if (!psc_dma) {
 395                 ret = -ENOMEM;
 396                 goto out_unmap;
 397         }
 398
 399         /* Get the PSC ID */
 400         prop = of_get_property(op->dev.of_node, "cell-index", &size);
 401         if (!prop || size < sizeof *prop) {
 402                 ret = -ENODEV;
 403                 goto out_free;
 404         }
 405
 406         spin_lock_init(&psc_dma->lock);
 407         mutex_init(&psc_dma->mutex);
 408         psc_dma->id = be32_to_cpu(*prop);
 409         psc_dma->irq = irq;
 410         psc_dma->psc_regs = regs;
 411         psc_dma->fifo_regs = regs + sizeof *psc_dma->psc_regs;
 412         psc_dma->dev = &op->dev;
 413         psc_dma->playback.psc_dma = psc_dma;
 414         psc_dma->capture.psc_dma = psc_dma;
 415         snprintf(psc_dma->name, sizeof psc_dma->name, "PSC%u", psc_dma->id);
 416
 417         /* Find the address of the fifo data registers and setup the
 418          * DMA tasks */
 419         fifo = res.start + offsetof(struct mpc52xx_psc, buffer.buffer_32);
 420         psc_dma->capture.bcom_task =
 421                 bcom_psc_gen_bd_rx_init(psc_dma->id, 10, fifo, 512);
 422         psc_dma->playback.bcom_task =
 423                 bcom_psc_gen_bd_tx_init(psc_dma->id, 10, fifo);
 424         if (!psc_dma->capture.bcom_task ||
 425             !psc_dma->playback.bcom_task) {
 426                 dev_err(&op->dev, "Could not allocate bestcomm tasks\n");
 427                 ret = -ENODEV;
 428                 goto out_free;
 429         }
 430
 431         /* Disable all interrupts and reset the PSC */
 432         out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr);
 433          /* reset receiver */
 434         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_RX);
 435          /* reset transmitter */
 436         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_TX);
 437          /* reset error */
 438         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_ERR_STAT);
 439          /* reset mode */
 440         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_SEL_MODE_REG_1);
 441
 442         /* Set up mode register;
 443          * First write: RxRdy (FIFO Alarm) generates rx FIFO irq
 444          * Second write: register Normal mode for non loopback
 445          */
 446         out_8(&psc_dma->psc_regs->mode, 0);
 447         out_8(&psc_dma->psc_regs->mode, 0);
 448
 449         /* Set the TX and RX fifo alarm thresholds */
 450         out_be16(&psc_dma->fifo_regs->rfalarm, 0x100);
 451         out_8(&psc_dma->fifo_regs->rfcntl, 0x4);
 452         out_be16(&psc_dma->fifo_regs->tfalarm, 0x100);
 453         out_8(&psc_dma->fifo_regs->tfcntl, 0x7);
 454
 455         /* Lookup the IRQ numbers */
 456         psc_dma->playback.irq =
 457                 bcom_get_task_irq(psc_dma->playback.bcom_task);
 458         psc_dma->capture.irq =
 459                 bcom_get_task_irq(psc_dma->capture.bcom_task);
 460
 461         rc = request_irq(psc_dma->irq, &psc_dma_status_irq, IRQF_SHARED,
 462                          "psc-dma-status", psc_dma);
 463         rc |= request_irq(psc_dma->capture.irq, &psc_dma_bcom_irq, IRQF_SHARED,
 464                           "psc-dma-capture", &psc_dma->capture);
 465         rc |= request_irq(psc_dma->playback.irq, &psc_dma_bcom_irq, IRQF_SHARED,
 466                           "psc-dma-playback", &psc_dma->playback);
 467         if (rc) {
 468                 ret = -ENODEV;
 469                 goto out_irq;
 470         }
 471
 472         /* Save what we've done so it can be found again later */
 473         dev_set_drvdata(&op->dev, psc_dma);
 474
 475         /* Tell the ASoC OF helpers about it */
 476         return devm_snd_soc_register_component(&op->dev,
 477                                         &mpc5200_audio_dma_component, NULL, 0);
 478 out_irq:
 479         free_irq(psc_dma->irq, psc_dma);
 480         free_irq(psc_dma->capture.irq, &psc_dma->capture);
 481         free_irq(psc_dma->playback.irq, &psc_dma->playback);
 482 out_free:
 483         kfree(psc_dma);
 484 out_unmap:
 485         iounmap(regs);
 486         return ret;
 487 }
 488 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_create);
 489
 490 int mpc5200_audio_dma_destroy(struct platform_device *op)
 491 {
 492         struct psc_dma *psc_dma = dev_get_drvdata(&op->dev);
 493
 494         dev_dbg(&op->dev, "mpc5200_audio_dma_destroy()\n");
 495
 496         bcom_gen_bd_rx_release(psc_dma->capture.bcom_task);
 497         bcom_gen_bd_tx_release(psc_dma->playback.bcom_task);
 498
 499         /* Release irqs */
 500         free_irq(psc_dma->irq, psc_dma);
 501         free_irq(psc_dma->capture.irq, &psc_dma->capture);
 502         free_irq(psc_dma->playback.irq, &psc_dma->playback);
 503
 504         iounmap(psc_dma->psc_regs);
 505         kfree(psc_dma);
 506         dev_set_drvdata(&op->dev, NULL);
 507
 508         return 0;
 509 }
 510 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_destroy);
 511
 512 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
 513 MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver");
 514 MODULE_LICENSE("GPL");