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  * @component: triggered component
 111  * @substream: triggered substream
 112  * @cmd: triggered command
 113  *
 114  * This function is called by ALSA to start, stop, pause, and resume the DMA
 115  * transfer of data.
 116  */
 117 static int psc_dma_trigger(struct snd_soc_component *component,
 118                            struct snd_pcm_substream *substream, int cmd)
 119 {
 120         struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 121         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
 122         struct snd_pcm_runtime *runtime = substream->runtime;
 123         struct psc_dma_stream *s = to_psc_dma_stream(substream, psc_dma);
 124         struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
 125         u16 imr;
 126         unsigned long flags;
 127         int i;
 128
 129         switch (cmd) {
 130         case SNDRV_PCM_TRIGGER_START:
 131                 dev_dbg(psc_dma->dev, "START: stream=%i fbits=%u ps=%u #p=%u\n",
 132                         substream->pstr->stream, runtime->frame_bits,
 133                         (int)runtime->period_size, runtime->periods);
 134                 s->period_bytes = frames_to_bytes(runtime,
 135                                                   runtime->period_size);
 136                 s->period_next = 0;
 137                 s->period_current = 0;
 138                 s->active = 1;
 139                 s->period_count = 0;
 140                 s->runtime = runtime;
 141
 142                 /* Fill up the bestcomm bd queue and enable DMA.
 143                  * This will begin filling the PSC's fifo.
 144                  */
 145                 spin_lock_irqsave(&psc_dma->lock, flags);
 146
 147                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 148                         bcom_gen_bd_rx_reset(s->bcom_task);
 149                 else
 150                         bcom_gen_bd_tx_reset(s->bcom_task);
 151
 152                 for (i = 0; i < runtime->periods; i++)
 153                         if (!bcom_queue_full(s->bcom_task))
 154                                 psc_dma_bcom_enqueue_next_buffer(s);
 155
 156                 bcom_enable(s->bcom_task);
 157                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 158
 159                 out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
 160
 161                 break;
 162
 163         case SNDRV_PCM_TRIGGER_STOP:
 164                 dev_dbg(psc_dma->dev, "STOP: stream=%i periods_count=%i\n",
 165                         substream->pstr->stream, s->period_count);
 166                 s->active = 0;
 167
 168                 spin_lock_irqsave(&psc_dma->lock, flags);
 169                 bcom_disable(s->bcom_task);
 170                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 171                         bcom_gen_bd_rx_reset(s->bcom_task);
 172                 else
 173                         bcom_gen_bd_tx_reset(s->bcom_task);
 174                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 175
 176                 break;
 177
 178         default:
 179                 dev_dbg(psc_dma->dev, "unhandled trigger: stream=%i cmd=%i\n",
 180                         substream->pstr->stream, cmd);
 181                 return -EINVAL;
 182         }
 183
 184         /* Update interrupt enable settings */
 185         imr = 0;
 186         if (psc_dma->playback.active)
 187                 imr |= MPC52xx_PSC_IMR_TXEMP;
 188         if (psc_dma->capture.active)
 189                 imr |= MPC52xx_PSC_IMR_ORERR;
 190         out_be16(&regs->isr_imr.imr, psc_dma->imr | imr);
 191
 192         return 0;
 193 }
 194
 195
 196 /* ---------------------------------------------------------------------
 197  * The PSC DMA 'ASoC platform' driver
 198  *
 199  * Can be referenced by an 'ASoC machine' driver
 200  * This driver only deals with the audio bus; it doesn't have any
 201  * interaction with the attached codec
 202  */
 203
 204 static const struct snd_pcm_hardware psc_dma_hardware = {
 205         .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
 206                 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
 207                 SNDRV_PCM_INFO_BATCH,
 208         .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE |
 209                 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE,
 210         .period_bytes_max       = 1024 * 1024,
 211         .period_bytes_min       = 32,
 212         .periods_min            = 2,
 213         .periods_max            = 256,
 214         .buffer_bytes_max       = 2 * 1024 * 1024,
 215         .fifo_size              = 512,
 216 };
 217
 218 static int psc_dma_open(struct snd_soc_component *component,
 219                         struct snd_pcm_substream *substream)
 220 {
 221         struct snd_pcm_runtime *runtime = substream->runtime;
 222         struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 223         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
 224         struct psc_dma_stream *s;
 225         int rc;
 226
 227         dev_dbg(psc_dma->dev, "psc_dma_open(substream=%p)\n", substream);
 228
 229         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 230                 s = &psc_dma->capture;
 231         else
 232                 s = &psc_dma->playback;
 233
 234         snd_soc_set_runtime_hwparams(substream, &psc_dma_hardware);
 235
 236         rc = snd_pcm_hw_constraint_integer(runtime,
 237                 SNDRV_PCM_HW_PARAM_PERIODS);
 238         if (rc < 0) {
 239                 dev_err(substream->pcm->card->dev, "invalid buffer size\n");
 240                 return rc;
 241         }
 242
 243         s->stream = substream;
 244         return 0;
 245 }
 246
 247 static int psc_dma_close(struct snd_soc_component *component,
 248                          struct snd_pcm_substream *substream)
 249 {
 250         struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 251         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
 252         struct psc_dma_stream *s;
 253
 254         dev_dbg(psc_dma->dev, "psc_dma_close(substream=%p)\n", substream);
 255
 256         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 257                 s = &psc_dma->capture;
 258         else
 259                 s = &psc_dma->playback;
 260
 261         if (!psc_dma->playback.active &&
 262             !psc_dma->capture.active) {
 263
 264                 /* Disable all interrupts and reset the PSC */
 265                 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr);
 266                 out_8(&psc_dma->psc_regs->command, 4 << 4); /* reset error */
 267         }
 268         s->stream = NULL;
 269         return 0;
 270 }
 271
 272 static snd_pcm_uframes_t
 273 psc_dma_pointer(struct snd_soc_component *component,
 274                 struct snd_pcm_substream *substream)
 275 {
 276         struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 277         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
 278         struct psc_dma_stream *s;
 279         dma_addr_t count;
 280
 281         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 282                 s = &psc_dma->capture;
 283         else
 284                 s = &psc_dma->playback;
 285
 286         count = s->period_current * s->period_bytes;
 287
 288         return bytes_to_frames(substream->runtime, count);
 289 }
 290
 291 static int psc_dma_hw_params(struct snd_soc_component *component,
 292                              struct snd_pcm_substream *substream,
 293                              struct snd_pcm_hw_params *params)
 294 {
 295         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 296
 297         return 0;
 298 }
 299
 300 static int psc_dma_new(struct snd_soc_component *component,
 301                        struct snd_soc_pcm_runtime *rtd)
 302 {
 303         struct snd_card *card = rtd->card->snd_card;
 304         struct snd_soc_dai *dai = asoc_rtd_to_cpu(rtd, 0);
 305         struct snd_pcm *pcm = rtd->pcm;
 306         size_t size = psc_dma_hardware.buffer_bytes_max;
 307         int rc;
 308
 309         dev_dbg(component->dev, "psc_dma_new(card=%p, dai=%p, pcm=%p)\n",
 310                 card, dai, pcm);
 311
 312         rc = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
 313         if (rc)
 314                 return rc;
 315
 316         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
 317                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 318                                 size, &pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer);
 319                 if (rc)
 320                         goto playback_alloc_err;
 321         }
 322
 323         if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
 324                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 325                                 size, &pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream->dma_buffer);
 326                 if (rc)
 327                         goto capture_alloc_err;
 328         }
 329
 330         return 0;
 331
 332  capture_alloc_err:
 333         if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream)
 334                 snd_dma_free_pages(&pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream->dma_buffer);
 335
 336  playback_alloc_err:
 337         dev_err(card->dev, "Cannot allocate buffer(s)\n");
 338
 339         return -ENOMEM;
 340 }
 341
 342 static void psc_dma_free(struct snd_soc_component *component,
 343                          struct snd_pcm *pcm)
 344 {
 345         struct snd_pcm_substream *substream;
 346         int stream;
 347
 348         dev_dbg(component->dev, "psc_dma_free(pcm=%p)\n", pcm);
 349
 350         for (stream = 0; stream < 2; stream++) {
 351                 substream = pcm->streams[stream].substream;
 352                 if (substream) {
 353                         snd_dma_free_pages(&substream->dma_buffer);
 354                         substream->dma_buffer.area = NULL;
 355                         substream->dma_buffer.addr = 0;
 356                 }
 357         }
 358 }
 359
 360 static const struct snd_soc_component_driver mpc5200_audio_dma_component = {
 361         .name           = DRV_NAME,
 362         .open           = psc_dma_open,
 363         .close          = psc_dma_close,
 364         .hw_free        = psc_dma_hw_free,
 365         .pointer        = psc_dma_pointer,
 366         .trigger        = psc_dma_trigger,
 367         .hw_params      = psc_dma_hw_params,
 368         .pcm_construct  = psc_dma_new,
 369         .pcm_destruct   = psc_dma_free,
 370 };
 371
 372 int mpc5200_audio_dma_create(struct platform_device *op)
 373 {
 374         phys_addr_t fifo;
 375         struct psc_dma *psc_dma;
 376         struct resource res;
 377         int size, irq, rc;
 378         const __be32 *prop;
 379         void __iomem *regs;
 380         int ret;
 381
 382         /* Fetch the registers and IRQ of the PSC */
 383         irq = irq_of_parse_and_map(op->dev.of_node, 0);
 384         if (of_address_to_resource(op->dev.of_node, 0, &res)) {
 385                 dev_err(&op->dev, "Missing reg property\n");
 386                 return -ENODEV;
 387         }
 388         regs = ioremap(res.start, resource_size(&res));
 389         if (!regs) {
 390                 dev_err(&op->dev, "Could not map registers\n");
 391                 return -ENODEV;
 392         }
 393
 394         /* Allocate and initialize the driver private data */
 395         psc_dma = kzalloc(sizeof *psc_dma, GFP_KERNEL);
 396         if (!psc_dma) {
 397                 ret = -ENOMEM;
 398                 goto out_unmap;
 399         }
 400
 401         /* Get the PSC ID */
 402         prop = of_get_property(op->dev.of_node, "cell-index", &size);
 403         if (!prop || size < sizeof *prop) {
 404                 ret = -ENODEV;
 405                 goto out_free;
 406         }
 407
 408         spin_lock_init(&psc_dma->lock);
 409         mutex_init(&psc_dma->mutex);
 410         psc_dma->id = be32_to_cpu(*prop);
 411         psc_dma->irq = irq;
 412         psc_dma->psc_regs = regs;
 413         psc_dma->fifo_regs = regs + sizeof *psc_dma->psc_regs;
 414         psc_dma->dev = &op->dev;
 415         psc_dma->playback.psc_dma = psc_dma;
 416         psc_dma->capture.psc_dma = psc_dma;
 417         snprintf(psc_dma->name, sizeof psc_dma->name, "PSC%u", psc_dma->id);
 418
 419         /* Find the address of the fifo data registers and setup the
 420          * DMA tasks */
 421         fifo = res.start + offsetof(struct mpc52xx_psc, buffer.buffer_32);
 422         psc_dma->capture.bcom_task =
 423                 bcom_psc_gen_bd_rx_init(psc_dma->id, 10, fifo, 512);
 424         psc_dma->playback.bcom_task =
 425                 bcom_psc_gen_bd_tx_init(psc_dma->id, 10, fifo);
 426         if (!psc_dma->capture.bcom_task ||
 427             !psc_dma->playback.bcom_task) {
 428                 dev_err(&op->dev, "Could not allocate bestcomm tasks\n");
 429                 ret = -ENODEV;
 430                 goto out_free;
 431         }
 432
 433         /* Disable all interrupts and reset the PSC */
 434         out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr);
 435          /* reset receiver */
 436         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_RX);
 437          /* reset transmitter */
 438         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_TX);
 439          /* reset error */
 440         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_ERR_STAT);
 441          /* reset mode */
 442         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_SEL_MODE_REG_1);
 443
 444         /* Set up mode register;
 445          * First write: RxRdy (FIFO Alarm) generates rx FIFO irq
 446          * Second write: register Normal mode for non loopback
 447          */
 448         out_8(&psc_dma->psc_regs->mode, 0);
 449         out_8(&psc_dma->psc_regs->mode, 0);
 450
 451         /* Set the TX and RX fifo alarm thresholds */
 452         out_be16(&psc_dma->fifo_regs->rfalarm, 0x100);
 453         out_8(&psc_dma->fifo_regs->rfcntl, 0x4);
 454         out_be16(&psc_dma->fifo_regs->tfalarm, 0x100);
 455         out_8(&psc_dma->fifo_regs->tfcntl, 0x7);
 456
 457         /* Lookup the IRQ numbers */
 458         psc_dma->playback.irq =
 459                 bcom_get_task_irq(psc_dma->playback.bcom_task);
 460         psc_dma->capture.irq =
 461                 bcom_get_task_irq(psc_dma->capture.bcom_task);
 462
 463         rc = request_irq(psc_dma->irq, &psc_dma_status_irq, IRQF_SHARED,
 464                          "psc-dma-status", psc_dma);
 465         rc |= request_irq(psc_dma->capture.irq, &psc_dma_bcom_irq, IRQF_SHARED,
 466                           "psc-dma-capture", &psc_dma->capture);
 467         rc |= request_irq(psc_dma->playback.irq, &psc_dma_bcom_irq, IRQF_SHARED,
 468                           "psc-dma-playback", &psc_dma->playback);
 469         if (rc) {
 470                 ret = -ENODEV;
 471                 goto out_irq;
 472         }
 473
 474         /* Save what we've done so it can be found again later */
 475         dev_set_drvdata(&op->dev, psc_dma);
 476
 477         /* Tell the ASoC OF helpers about it */
 478         return devm_snd_soc_register_component(&op->dev,
 479                                         &mpc5200_audio_dma_component, NULL, 0);
 480 out_irq:
 481         free_irq(psc_dma->irq, psc_dma);
 482         free_irq(psc_dma->capture.irq, &psc_dma->capture);
 483         free_irq(psc_dma->playback.irq, &psc_dma->playback);
 484 out_free:
 485         kfree(psc_dma);
 486 out_unmap:
 487         iounmap(regs);
 488         return ret;
 489 }
 490 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_create);
 491
 492 int mpc5200_audio_dma_destroy(struct platform_device *op)
 493 {
 494         struct psc_dma *psc_dma = dev_get_drvdata(&op->dev);
 495
 496         dev_dbg(&op->dev, "mpc5200_audio_dma_destroy()\n");
 497
 498         bcom_gen_bd_rx_release(psc_dma->capture.bcom_task);
 499         bcom_gen_bd_tx_release(psc_dma->playback.bcom_task);
 500
 501         /* Release irqs */
 502         free_irq(psc_dma->irq, psc_dma);
 503         free_irq(psc_dma->capture.irq, &psc_dma->capture);
 504         free_irq(psc_dma->playback.irq, &psc_dma->playback);
 505
 506         iounmap(psc_dma->psc_regs);
 507         kfree(psc_dma);
 508         dev_set_drvdata(&op->dev, NULL);
 509
 510         return 0;
 511 }
 512 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_destroy);
 513
 514 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
 515 MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver");
 516 MODULE_LICENSE("GPL");