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