sound/soc/fsl/mpc5200_dma.c

   1 /*
   2  * Freescale MPC5200 PSC DMA
   3  * ALSA SoC Platform driver
   4  *
   5  * Copyright (C) 2008 Secret Lab Technologies Ltd.
   6  * Copyright (C) 2009 Jon Smirl, Digispeaker
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/of_device.h>
  11
  12 #include <sound/soc.h>
  13
  14 #include <sysdev/bestcomm/bestcomm.h>
  15 #include <sysdev/bestcomm/gen_bd.h>
  16 #include <asm/mpc52xx_psc.h>
  17
  18 #include "mpc5200_dma.h"
  19
  20 /*
  21  * Interrupt handlers
  22  */
  23 static irqreturn_t psc_dma_status_irq(int irq, void *_psc_dma)
  24 {
  25         struct psc_dma *psc_dma = _psc_dma;
  26         struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
  27         u16 isr;
  28
  29         isr = in_be16(&regs->mpc52xx_psc_isr);
  30
  31         /* Playback underrun error */
  32         if (psc_dma->playback.active && (isr & MPC52xx_PSC_IMR_TXEMP))
  33                 psc_dma->stats.underrun_count++;
  34
  35         /* Capture overrun error */
  36         if (psc_dma->capture.active && (isr & MPC52xx_PSC_IMR_ORERR))
  37                 psc_dma->stats.overrun_count++;
  38
  39         out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
  40
  41         return IRQ_HANDLED;
  42 }
  43
  44 /**
  45  * psc_dma_bcom_enqueue_next_buffer - Enqueue another audio buffer
  46  * @s: pointer to stream private data structure
  47  *
  48  * Enqueues another audio period buffer into the bestcomm queue.
  49  *
  50  * Note: The routine must only be called when there is space available in
  51  * the queue.  Otherwise the enqueue will fail and the audio ring buffer
  52  * will get out of sync
  53  */
  54 static void psc_dma_bcom_enqueue_next_buffer(struct psc_dma_stream *s)
  55 {
  56         struct bcom_bd *bd;
  57
  58         /* Prepare and enqueue the next buffer descriptor */
  59         bd = bcom_prepare_next_buffer(s->bcom_task);
  60         bd->status = s->period_bytes;
  61         bd->data[0] = s->period_next_pt;
  62         bcom_submit_next_buffer(s->bcom_task, NULL);
  63
  64         /* Update for next period */
  65         s->period_next_pt += s->period_bytes;
  66         if (s->period_next_pt >= s->period_end)
  67                 s->period_next_pt = s->period_start;
  68 }
  69
  70 static void psc_dma_bcom_enqueue_tx(struct psc_dma_stream *s)
  71 {
  72         while (s->appl_ptr < s->runtime->control->appl_ptr) {
  73
  74                 if (bcom_queue_full(s->bcom_task))
  75                         return;
  76
  77                 s->appl_ptr += s->period_size;
  78
  79                 psc_dma_bcom_enqueue_next_buffer(s);
  80         }
  81 }
  82
  83 /* Bestcomm DMA irq handler */
  84 static irqreturn_t psc_dma_bcom_irq_tx(int irq, void *_psc_dma_stream)
  85 {
  86         struct psc_dma_stream *s = _psc_dma_stream;
  87
  88         spin_lock(&s->psc_dma->lock);
  89         /* For each finished period, dequeue the completed period buffer
  90          * and enqueue a new one in it's place. */
  91         while (bcom_buffer_done(s->bcom_task)) {
  92                 bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
  93
  94                 s->period_current_pt += s->period_bytes;
  95                 if (s->period_current_pt >= s->period_end)
  96                         s->period_current_pt = s->period_start;
  97         }
  98         psc_dma_bcom_enqueue_tx(s);
  99         spin_unlock(&s->psc_dma->lock);
 100
 101         /* If the stream is active, then also inform the PCM middle layer
 102          * of the period finished event. */
 103         if (s->active)
 104                 snd_pcm_period_elapsed(s->stream);
 105
 106         return IRQ_HANDLED;
 107 }
 108
 109 static irqreturn_t psc_dma_bcom_irq_rx(int irq, void *_psc_dma_stream)
 110 {
 111         struct psc_dma_stream *s = _psc_dma_stream;
 112
 113         spin_lock(&s->psc_dma->lock);
 114         /* For each finished period, dequeue the completed period buffer
 115          * and enqueue a new one in it's place. */
 116         while (bcom_buffer_done(s->bcom_task)) {
 117                 bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
 118
 119                 s->period_current_pt += s->period_bytes;
 120                 if (s->period_current_pt >= s->period_end)
 121                         s->period_current_pt = s->period_start;
 122
 123                 psc_dma_bcom_enqueue_next_buffer(s);
 124         }
 125         spin_unlock(&s->psc_dma->lock);
 126
 127         /* If the stream is active, then also inform the PCM middle layer
 128          * of the period finished event. */
 129         if (s->active)
 130                 snd_pcm_period_elapsed(s->stream);
 131
 132         return IRQ_HANDLED;
 133 }
 134
 135 static int psc_dma_hw_free(struct snd_pcm_substream *substream)
 136 {
 137         snd_pcm_set_runtime_buffer(substream, NULL);
 138         return 0;
 139 }
 140
 141 /**
 142  * psc_dma_trigger: start and stop the DMA transfer.
 143  *
 144  * This function is called by ALSA to start, stop, pause, and resume the DMA
 145  * transfer of data.
 146  */
 147 static int psc_dma_trigger(struct snd_pcm_substream *substream, int cmd)
 148 {
 149         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 150         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 151         struct snd_pcm_runtime *runtime = substream->runtime;
 152         struct psc_dma_stream *s;
 153         struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
 154         u16 imr;
 155         unsigned long flags;
 156         int i;
 157
 158         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 159                 s = &psc_dma->capture;
 160         else
 161                 s = &psc_dma->playback;
 162
 163         dev_dbg(psc_dma->dev, "psc_dma_trigger(substream=%p, cmd=%i)"
 164                 " stream_id=%i\n",
 165                 substream, cmd, substream->pstr->stream);
 166
 167         switch (cmd) {
 168         case SNDRV_PCM_TRIGGER_START:
 169                 s->period_bytes = frames_to_bytes(runtime,
 170                                                   runtime->period_size);
 171                 s->period_start = virt_to_phys(runtime->dma_area);
 172                 s->period_end = s->period_start +
 173                                 (s->period_bytes * runtime->periods);
 174                 s->period_next_pt = s->period_start;
 175                 s->period_current_pt = s->period_start;
 176                 s->period_size = runtime->period_size;
 177                 s->active = 1;
 178
 179                 /* track appl_ptr so that we have a better chance of detecting
 180                  * end of stream and not over running it.
 181                  */
 182                 s->runtime = runtime;
 183                 s->appl_ptr = s->runtime->control->appl_ptr -
 184                                 (runtime->period_size * runtime->periods);
 185
 186                 /* Fill up the bestcomm bd queue and enable DMA.
 187                  * This will begin filling the PSC's fifo.
 188                  */
 189                 spin_lock_irqsave(&psc_dma->lock, flags);
 190
 191                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) {
 192                         bcom_gen_bd_rx_reset(s->bcom_task);
 193                         for (i = 0; i < runtime->periods; i++)
 194                                 if (!bcom_queue_full(s->bcom_task))
 195                                         psc_dma_bcom_enqueue_next_buffer(s);
 196                 } else {
 197                         bcom_gen_bd_tx_reset(s->bcom_task);
 198                         psc_dma_bcom_enqueue_tx(s);
 199                 }
 200
 201                 bcom_enable(s->bcom_task);
 202                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 203
 204                 out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
 205
 206                 break;
 207
 208         case SNDRV_PCM_TRIGGER_STOP:
 209                 s->active = 0;
 210
 211                 spin_lock_irqsave(&psc_dma->lock, flags);
 212                 bcom_disable(s->bcom_task);
 213                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 214                         bcom_gen_bd_rx_reset(s->bcom_task);
 215                 else
 216                         bcom_gen_bd_tx_reset(s->bcom_task);
 217                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 218
 219                 break;
 220
 221         default:
 222                 dev_dbg(psc_dma->dev, "invalid command\n");
 223                 return -EINVAL;
 224         }
 225
 226         /* Update interrupt enable settings */
 227         imr = 0;
 228         if (psc_dma->playback.active)
 229                 imr |= MPC52xx_PSC_IMR_TXEMP;
 230         if (psc_dma->capture.active)
 231                 imr |= MPC52xx_PSC_IMR_ORERR;
 232         out_be16(&regs->isr_imr.imr, psc_dma->imr | imr);
 233
 234         return 0;
 235 }
 236
 237
 238 /* ---------------------------------------------------------------------
 239  * The PSC DMA 'ASoC platform' driver
 240  *
 241  * Can be referenced by an 'ASoC machine' driver
 242  * This driver only deals with the audio bus; it doesn't have any
 243  * interaction with the attached codec
 244  */
 245
 246 static const struct snd_pcm_hardware psc_dma_hardware = {
 247         .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
 248                 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
 249                 SNDRV_PCM_INFO_BATCH,
 250         .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE |
 251                 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE,
 252         .rate_min = 8000,
 253         .rate_max = 48000,
 254         .channels_min = 1,
 255         .channels_max = 2,
 256         .period_bytes_max       = 1024 * 1024,
 257         .period_bytes_min       = 32,
 258         .periods_min            = 2,
 259         .periods_max            = 256,
 260         .buffer_bytes_max       = 2 * 1024 * 1024,
 261         .fifo_size              = 512,
 262 };
 263
 264 static int psc_dma_open(struct snd_pcm_substream *substream)
 265 {
 266         struct snd_pcm_runtime *runtime = substream->runtime;
 267         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 268         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 269         struct psc_dma_stream *s;
 270         int rc;
 271
 272         dev_dbg(psc_dma->dev, "psc_dma_open(substream=%p)\n", substream);
 273
 274         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 275                 s = &psc_dma->capture;
 276         else
 277                 s = &psc_dma->playback;
 278
 279         snd_soc_set_runtime_hwparams(substream, &psc_dma_hardware);
 280
 281         rc = snd_pcm_hw_constraint_integer(runtime,
 282                 SNDRV_PCM_HW_PARAM_PERIODS);
 283         if (rc < 0) {
 284                 dev_err(substream->pcm->card->dev, "invalid buffer size\n");
 285                 return rc;
 286         }
 287
 288         s->stream = substream;
 289         return 0;
 290 }
 291
 292 static int psc_dma_close(struct snd_pcm_substream *substream)
 293 {
 294         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 295         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 296         struct psc_dma_stream *s;
 297
 298         dev_dbg(psc_dma->dev, "psc_dma_close(substream=%p)\n", substream);
 299
 300         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 301                 s = &psc_dma->capture;
 302         else
 303                 s = &psc_dma->playback;
 304
 305         if (!psc_dma->playback.active &&
 306             !psc_dma->capture.active) {
 307
 308                 /* Disable all interrupts and reset the PSC */
 309                 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr);
 310                 out_8(&psc_dma->psc_regs->command, 4 << 4); /* reset error */
 311         }
 312         s->stream = NULL;
 313         return 0;
 314 }
 315
 316 static snd_pcm_uframes_t
 317 psc_dma_pointer(struct snd_pcm_substream *substream)
 318 {
 319         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 320         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 321         struct psc_dma_stream *s;
 322         dma_addr_t count;
 323
 324         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 325                 s = &psc_dma->capture;
 326         else
 327                 s = &psc_dma->playback;
 328
 329         count = s->period_current_pt - s->period_start;
 330
 331         return bytes_to_frames(substream->runtime, count);
 332 }
 333
 334 static int
 335 psc_dma_hw_params(struct snd_pcm_substream *substream,
 336                          struct snd_pcm_hw_params *params)
 337 {
 338         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 339
 340         return 0;
 341 }
 342
 343 static struct snd_pcm_ops psc_dma_ops = {
 344         .open           = psc_dma_open,
 345         .close          = psc_dma_close,
 346         .hw_free        = psc_dma_hw_free,
 347         .ioctl          = snd_pcm_lib_ioctl,
 348         .pointer        = psc_dma_pointer,
 349         .trigger        = psc_dma_trigger,
 350         .hw_params      = psc_dma_hw_params,
 351 };
 352
 353 static u64 psc_dma_dmamask = 0xffffffff;
 354 static int psc_dma_new(struct snd_card *card, struct snd_soc_dai *dai,
 355                            struct snd_pcm *pcm)
 356 {
 357         struct snd_soc_pcm_runtime *rtd = pcm->private_data;
 358         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 359         size_t size = psc_dma_hardware.buffer_bytes_max;
 360         int rc = 0;
 361
 362         dev_dbg(rtd->socdev->dev, "psc_dma_new(card=%p, dai=%p, pcm=%p)\n",
 363                 card, dai, pcm);
 364
 365         if (!card->dev->dma_mask)
 366                 card->dev->dma_mask = &psc_dma_dmamask;
 367         if (!card->dev->coherent_dma_mask)
 368                 card->dev->coherent_dma_mask = 0xffffffff;
 369
 370         if (pcm->streams[0].substream) {
 371                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 372                                 size, &pcm->streams[0].substream->dma_buffer);
 373                 if (rc)
 374                         goto playback_alloc_err;
 375         }
 376
 377         if (pcm->streams[1].substream) {
 378                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 379                                 size, &pcm->streams[1].substream->dma_buffer);
 380                 if (rc)
 381                         goto capture_alloc_err;
 382         }
 383
 384         if (rtd->socdev->card->codec->ac97)
 385                 rtd->socdev->card->codec->ac97->private_data = psc_dma;
 386
 387         return 0;
 388
 389  capture_alloc_err:
 390         if (pcm->streams[0].substream)
 391                 snd_dma_free_pages(&pcm->streams[0].substream->dma_buffer);
 392
 393  playback_alloc_err:
 394         dev_err(card->dev, "Cannot allocate buffer(s)\n");
 395
 396         return -ENOMEM;
 397 }
 398
 399 static void psc_dma_free(struct snd_pcm *pcm)
 400 {
 401         struct snd_soc_pcm_runtime *rtd = pcm->private_data;
 402         struct snd_pcm_substream *substream;
 403         int stream;
 404
 405         dev_dbg(rtd->socdev->dev, "psc_dma_free(pcm=%p)\n", pcm);
 406
 407         for (stream = 0; stream < 2; stream++) {
 408                 substream = pcm->streams[stream].substream;
 409                 if (substream) {
 410                         snd_dma_free_pages(&substream->dma_buffer);
 411                         substream->dma_buffer.area = NULL;
 412                         substream->dma_buffer.addr = 0;
 413                 }
 414         }
 415 }
 416
 417 struct snd_soc_platform mpc5200_audio_dma_platform = {
 418         .name           = "mpc5200-psc-audio",
 419         .pcm_ops        = &psc_dma_ops,
 420         .pcm_new        = &psc_dma_new,
 421         .pcm_free       = &psc_dma_free,
 422 };
 423 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_platform);
 424
 425 int mpc5200_audio_dma_create(struct of_device *op)
 426 {
 427         phys_addr_t fifo;
 428         struct psc_dma *psc_dma;
 429         struct resource res;
 430         int size, irq, rc;
 431         const __be32 *prop;
 432         void __iomem *regs;
 433
 434         /* Fetch the registers and IRQ of the PSC */
 435         irq = irq_of_parse_and_map(op->node, 0);
 436         if (of_address_to_resource(op->node, 0, &res)) {
 437                 dev_err(&op->dev, "Missing reg property\n");
 438                 return -ENODEV;
 439         }
 440         regs = ioremap(res.start, 1 + res.end - res.start);
 441         if (!regs) {
 442                 dev_err(&op->dev, "Could not map registers\n");
 443                 return -ENODEV;
 444         }
 445
 446         /* Allocate and initialize the driver private data */
 447         psc_dma = kzalloc(sizeof *psc_dma, GFP_KERNEL);
 448         if (!psc_dma) {
 449                 iounmap(regs);
 450                 return -ENOMEM;
 451         }
 452
 453         /* Get the PSC ID */
 454         prop = of_get_property(op->node, "cell-index", &size);
 455         if (!prop || size < sizeof *prop)
 456                 return -ENODEV;
 457
 458         spin_lock_init(&psc_dma->lock);
 459         mutex_init(&psc_dma->mutex);
 460         psc_dma->id = be32_to_cpu(*prop);
 461         psc_dma->irq = irq;
 462         psc_dma->psc_regs = regs;
 463         psc_dma->fifo_regs = regs + sizeof *psc_dma->psc_regs;
 464         psc_dma->dev = &op->dev;
 465         psc_dma->playback.psc_dma = psc_dma;
 466         psc_dma->capture.psc_dma = psc_dma;
 467         snprintf(psc_dma->name, sizeof psc_dma->name, "PSC%u", psc_dma->id);
 468
 469         /* Find the address of the fifo data registers and setup the
 470          * DMA tasks */
 471         fifo = res.start + offsetof(struct mpc52xx_psc, buffer.buffer_32);
 472         psc_dma->capture.bcom_task =
 473                 bcom_psc_gen_bd_rx_init(psc_dma->id, 10, fifo, 512);
 474         psc_dma->playback.bcom_task =
 475                 bcom_psc_gen_bd_tx_init(psc_dma->id, 10, fifo);
 476         if (!psc_dma->capture.bcom_task ||
 477             !psc_dma->playback.bcom_task) {
 478                 dev_err(&op->dev, "Could not allocate bestcomm tasks\n");
 479                 iounmap(regs);
 480                 kfree(psc_dma);
 481                 return -ENODEV;
 482         }
 483
 484         /* Disable all interrupts and reset the PSC */
 485         out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr);
 486          /* reset receiver */
 487         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_RX);
 488          /* reset transmitter */
 489         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_TX);
 490          /* reset error */
 491         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_ERR_STAT);
 492          /* reset mode */
 493         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_SEL_MODE_REG_1);
 494
 495         /* Set up mode register;
 496          * First write: RxRdy (FIFO Alarm) generates rx FIFO irq
 497          * Second write: register Normal mode for non loopback
 498          */
 499         out_8(&psc_dma->psc_regs->mode, 0);
 500         out_8(&psc_dma->psc_regs->mode, 0);
 501
 502         /* Set the TX and RX fifo alarm thresholds */
 503         out_be16(&psc_dma->fifo_regs->rfalarm, 0x100);
 504         out_8(&psc_dma->fifo_regs->rfcntl, 0x4);
 505         out_be16(&psc_dma->fifo_regs->tfalarm, 0x100);
 506         out_8(&psc_dma->fifo_regs->tfcntl, 0x7);
 507
 508         /* Lookup the IRQ numbers */
 509         psc_dma->playback.irq =
 510                 bcom_get_task_irq(psc_dma->playback.bcom_task);
 511         psc_dma->capture.irq =
 512                 bcom_get_task_irq(psc_dma->capture.bcom_task);
 513
 514         rc = request_irq(psc_dma->irq, &psc_dma_status_irq, IRQF_SHARED,
 515                          "psc-dma-status", psc_dma);
 516         rc |= request_irq(psc_dma->capture.irq,
 517                           &psc_dma_bcom_irq_rx, IRQF_SHARED,
 518                           "psc-dma-capture", &psc_dma->capture);
 519         rc |= request_irq(psc_dma->playback.irq,
 520                           &psc_dma_bcom_irq_tx, IRQF_SHARED,
 521                           "psc-dma-playback", &psc_dma->playback);
 522         if (rc) {
 523                 free_irq(psc_dma->irq, psc_dma);
 524                 free_irq(psc_dma->capture.irq,
 525                          &psc_dma->capture);
 526                 free_irq(psc_dma->playback.irq,
 527                          &psc_dma->playback);
 528                 return -ENODEV;
 529         }
 530
 531         /* Save what we've done so it can be found again later */
 532         dev_set_drvdata(&op->dev, psc_dma);
 533
 534         /* Tell the ASoC OF helpers about it */
 535         return snd_soc_register_platform(&mpc5200_audio_dma_platform);
 536 }
 537 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_create);
 538
 539 int mpc5200_audio_dma_destroy(struct of_device *op)
 540 {
 541         struct psc_dma *psc_dma = dev_get_drvdata(&op->dev);
 542
 543         dev_dbg(&op->dev, "mpc5200_audio_dma_destroy()\n");
 544
 545         snd_soc_unregister_platform(&mpc5200_audio_dma_platform);
 546
 547         bcom_gen_bd_rx_release(psc_dma->capture.bcom_task);
 548         bcom_gen_bd_tx_release(psc_dma->playback.bcom_task);
 549
 550         /* Release irqs */
 551         free_irq(psc_dma->irq, psc_dma);
 552         free_irq(psc_dma->capture.irq, &psc_dma->capture);
 553         free_irq(psc_dma->playback.irq, &psc_dma->playback);
 554
 555         iounmap(psc_dma->psc_regs);
 556         kfree(psc_dma);
 557         dev_set_drvdata(&op->dev, NULL);
 558
 559         return 0;
 560 }
 561 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_destroy);
 562
 563 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
 564 MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver");
 565 MODULE_LICENSE("GPL");