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