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/slab.h>
  12
  13 #include <sound/soc.h>
  14
  15 #include <sysdev/bestcomm/bestcomm.h>
  16 #include <sysdev/bestcomm/gen_bd.h>
  17 #include <asm/mpc52xx_psc.h>
  18
  19 #include "mpc5200_dma.h"
  20
  21 /*
  22  * Interrupt handlers
  23  */
  24 static irqreturn_t psc_dma_status_irq(int irq, void *_psc_dma)
  25 {
  26         struct psc_dma *psc_dma = _psc_dma;
  27         struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
  28         u16 isr;
  29
  30         isr = in_be16(&regs->mpc52xx_psc_isr);
  31
  32         /* Playback underrun error */
  33         if (psc_dma->playback.active && (isr & MPC52xx_PSC_IMR_TXEMP))
  34                 psc_dma->stats.underrun_count++;
  35
  36         /* Capture overrun error */
  37         if (psc_dma->capture.active && (isr & MPC52xx_PSC_IMR_ORERR))
  38                 psc_dma->stats.overrun_count++;
  39
  40         out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
  41
  42         return IRQ_HANDLED;
  43 }
  44
  45 /**
  46  * psc_dma_bcom_enqueue_next_buffer - Enqueue another audio buffer
  47  * @s: pointer to stream private data structure
  48  *
  49  * Enqueues another audio period buffer into the bestcomm queue.
  50  *
  51  * Note: The routine must only be called when there is space available in
  52  * the queue.  Otherwise the enqueue will fail and the audio ring buffer
  53  * will get out of sync
  54  */
  55 static void psc_dma_bcom_enqueue_next_buffer(struct psc_dma_stream *s)
  56 {
  57         struct bcom_bd *bd;
  58
  59         /* Prepare and enqueue the next buffer descriptor */
  60         bd = bcom_prepare_next_buffer(s->bcom_task);
  61         bd->status = s->period_bytes;
  62         bd->data[0] = s->runtime->dma_addr + (s->period_next * s->period_bytes);
  63         bcom_submit_next_buffer(s->bcom_task, NULL);
  64
  65         /* Update for next period */
  66         s->period_next = (s->period_next + 1) % s->runtime->periods;
  67 }
  68
  69 /* Bestcomm DMA irq handler */
  70 static irqreturn_t psc_dma_bcom_irq(int irq, void *_psc_dma_stream)
  71 {
  72         struct psc_dma_stream *s = _psc_dma_stream;
  73
  74         spin_lock(&s->psc_dma->lock);
  75         /* For each finished period, dequeue the completed period buffer
  76          * and enqueue a new one in it's place. */
  77         while (bcom_buffer_done(s->bcom_task)) {
  78                 bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
  79
  80                 s->period_current = (s->period_current+1) % s->runtime->periods;
  81                 s->period_count++;
  82
  83                 psc_dma_bcom_enqueue_next_buffer(s);
  84         }
  85         spin_unlock(&s->psc_dma->lock);
  86
  87         /* If the stream is active, then also inform the PCM middle layer
  88          * of the period finished event. */
  89         if (s->active)
  90                 snd_pcm_period_elapsed(s->stream);
  91
  92         return IRQ_HANDLED;
  93 }
  94
  95 static int psc_dma_hw_free(struct snd_pcm_substream *substream)
  96 {
  97         snd_pcm_set_runtime_buffer(substream, NULL);
  98         return 0;
  99 }
 100
 101 /**
 102  * psc_dma_trigger: start and stop the DMA transfer.
 103  *
 104  * This function is called by ALSA to start, stop, pause, and resume the DMA
 105  * transfer of data.
 106  */
 107 static int psc_dma_trigger(struct snd_pcm_substream *substream, int cmd)
 108 {
 109         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 110         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 111         struct snd_pcm_runtime *runtime = substream->runtime;
 112         struct psc_dma_stream *s = to_psc_dma_stream(substream, psc_dma);
 113         struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
 114         u16 imr;
 115         unsigned long flags;
 116         int i;
 117
 118         switch (cmd) {
 119         case SNDRV_PCM_TRIGGER_START:
 120                 dev_dbg(psc_dma->dev, "START: stream=%i fbits=%u ps=%u #p=%u\n",
 121                         substream->pstr->stream, runtime->frame_bits,
 122                         (int)runtime->period_size, runtime->periods);
 123                 s->period_bytes = frames_to_bytes(runtime,
 124                                                   runtime->period_size);
 125                 s->period_next = 0;
 126                 s->period_current = 0;
 127                 s->active = 1;
 128                 s->period_count = 0;
 129                 s->runtime = runtime;
 130
 131                 /* Fill up the bestcomm bd queue and enable DMA.
 132                  * This will begin filling the PSC's fifo.
 133                  */
 134                 spin_lock_irqsave(&psc_dma->lock, flags);
 135
 136                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 137                         bcom_gen_bd_rx_reset(s->bcom_task);
 138                 else
 139                         bcom_gen_bd_tx_reset(s->bcom_task);
 140
 141                 for (i = 0; i < runtime->periods; i++)
 142                         if (!bcom_queue_full(s->bcom_task))
 143                                 psc_dma_bcom_enqueue_next_buffer(s);
 144
 145                 bcom_enable(s->bcom_task);
 146                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 147
 148                 out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
 149
 150                 break;
 151
 152         case SNDRV_PCM_TRIGGER_STOP:
 153                 dev_dbg(psc_dma->dev, "STOP: stream=%i periods_count=%i\n",
 154                         substream->pstr->stream, s->period_count);
 155                 s->active = 0;
 156
 157                 spin_lock_irqsave(&psc_dma->lock, flags);
 158                 bcom_disable(s->bcom_task);
 159                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 160                         bcom_gen_bd_rx_reset(s->bcom_task);
 161                 else
 162                         bcom_gen_bd_tx_reset(s->bcom_task);
 163                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 164
 165                 break;
 166
 167         default:
 168                 dev_dbg(psc_dma->dev, "unhandled trigger: stream=%i cmd=%i\n",
 169                         substream->pstr->stream, cmd);
 170                 return -EINVAL;
 171         }
 172
 173         /* Update interrupt enable settings */
 174         imr = 0;
 175         if (psc_dma->playback.active)
 176                 imr |= MPC52xx_PSC_IMR_TXEMP;
 177         if (psc_dma->capture.active)
 178                 imr |= MPC52xx_PSC_IMR_ORERR;
 179         out_be16(&regs->isr_imr.imr, psc_dma->imr | imr);
 180
 181         return 0;
 182 }
 183
 184
 185 /* ---------------------------------------------------------------------
 186  * The PSC DMA 'ASoC platform' driver
 187  *
 188  * Can be referenced by an 'ASoC machine' driver
 189  * This driver only deals with the audio bus; it doesn't have any
 190  * interaction with the attached codec
 191  */
 192
 193 static const struct snd_pcm_hardware psc_dma_hardware = {
 194         .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
 195                 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
 196                 SNDRV_PCM_INFO_BATCH,
 197         .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE |
 198                 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE,
 199         .rate_min = 8000,
 200         .rate_max = 48000,
 201         .channels_min = 1,
 202         .channels_max = 2,
 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 = rtd->dai->cpu_dai->private_data;
 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 = rtd->dai->cpu_dai->private_data;
 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 = rtd->dai->cpu_dai->private_data;
 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 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 u64 psc_dma_dmamask = 0xffffffff;
 301 static int psc_dma_new(struct snd_card *card, struct snd_soc_dai *dai,
 302                            struct snd_pcm *pcm)
 303 {
 304         struct snd_soc_pcm_runtime *rtd = pcm->private_data;
 305         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 306         size_t size = psc_dma_hardware.buffer_bytes_max;
 307         int rc = 0;
 308
 309         dev_dbg(rtd->socdev->dev, "psc_dma_new(card=%p, dai=%p, pcm=%p)\n",
 310                 card, dai, pcm);
 311
 312         if (!card->dev->dma_mask)
 313                 card->dev->dma_mask = &psc_dma_dmamask;
 314         if (!card->dev->coherent_dma_mask)
 315                 card->dev->coherent_dma_mask = 0xffffffff;
 316
 317         if (pcm->streams[0].substream) {
 318                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 319                                 size, &pcm->streams[0].substream->dma_buffer);
 320                 if (rc)
 321                         goto playback_alloc_err;
 322         }
 323
 324         if (pcm->streams[1].substream) {
 325                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 326                                 size, &pcm->streams[1].substream->dma_buffer);
 327                 if (rc)
 328                         goto capture_alloc_err;
 329         }
 330
 331         if (rtd->socdev->card->codec->ac97)
 332                 rtd->socdev->card->codec->ac97->private_data = psc_dma;
 333
 334         return 0;
 335
 336  capture_alloc_err:
 337         if (pcm->streams[0].substream)
 338                 snd_dma_free_pages(&pcm->streams[0].substream->dma_buffer);
 339
 340  playback_alloc_err:
 341         dev_err(card->dev, "Cannot allocate buffer(s)\n");
 342
 343         return -ENOMEM;
 344 }
 345
 346 static void psc_dma_free(struct snd_pcm *pcm)
 347 {
 348         struct snd_soc_pcm_runtime *rtd = pcm->private_data;
 349         struct snd_pcm_substream *substream;
 350         int stream;
 351
 352         dev_dbg(rtd->socdev->dev, "psc_dma_free(pcm=%p)\n", pcm);
 353
 354         for (stream = 0; stream < 2; stream++) {
 355                 substream = pcm->streams[stream].substream;
 356                 if (substream) {
 357                         snd_dma_free_pages(&substream->dma_buffer);
 358                         substream->dma_buffer.area = NULL;
 359                         substream->dma_buffer.addr = 0;
 360                 }
 361         }
 362 }
 363
 364 struct snd_soc_platform mpc5200_audio_dma_platform = {
 365         .name           = "mpc5200-psc-audio",
 366         .pcm_ops        = &psc_dma_ops,
 367         .pcm_new        = &psc_dma_new,
 368         .pcm_free       = &psc_dma_free,
 369 };
 370 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_platform);
 371
 372 int mpc5200_audio_dma_create(struct of_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, 1 + res.end - res.start);
 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 snd_soc_register_platform(&mpc5200_audio_dma_platform);
 479 out_irq:
 480         free_irq(psc_dma->irq, psc_dma);
 481         free_irq(psc_dma->capture.irq, &psc_dma->capture);
 482         free_irq(psc_dma->playback.irq, &psc_dma->playback);
 483 out_free:
 484         kfree(psc_dma);
 485 out_unmap:
 486         iounmap(regs);
 487         return ret;
 488 }
 489 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_create);
 490
 491 int mpc5200_audio_dma_destroy(struct of_device *op)
 492 {
 493         struct psc_dma *psc_dma = dev_get_drvdata(&op->dev);
 494
 495         dev_dbg(&op->dev, "mpc5200_audio_dma_destroy()\n");
 496
 497         snd_soc_unregister_platform(&mpc5200_audio_dma_platform);
 498
 499         bcom_gen_bd_rx_release(psc_dma->capture.bcom_task);
 500         bcom_gen_bd_tx_release(psc_dma->playback.bcom_task);
 501
 502         /* Release irqs */
 503         free_irq(psc_dma->irq, psc_dma);
 504         free_irq(psc_dma->capture.irq, &psc_dma->capture);
 505         free_irq(psc_dma->playback.irq, &psc_dma->playback);
 506
 507         iounmap(psc_dma->psc_regs);
 508         kfree(psc_dma);
 509         dev_set_drvdata(&op->dev, NULL);
 510
 511         return 0;
 512 }
 513 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_destroy);
 514
 515 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
 516 MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver");
 517 MODULE_LICENSE("GPL");