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 #include <linux/of_platform.h>
  13
  14 #include <sound/soc.h>
  15
  16 #include <sysdev/bestcomm/bestcomm.h>
  17 #include <sysdev/bestcomm/gen_bd.h>
  18 #include <asm/mpc52xx_psc.h>
  19
  20 #include "mpc5200_dma.h"
  21
  22 /*
  23  * Interrupt handlers
  24  */
  25 static irqreturn_t psc_dma_status_irq(int irq, void *_psc_dma)
  26 {
  27         struct psc_dma *psc_dma = _psc_dma;
  28         struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
  29         u16 isr;
  30
  31         isr = in_be16(&regs->mpc52xx_psc_isr);
  32
  33         /* Playback underrun error */
  34         if (psc_dma->playback.active && (isr & MPC52xx_PSC_IMR_TXEMP))
  35                 psc_dma->stats.underrun_count++;
  36
  37         /* Capture overrun error */
  38         if (psc_dma->capture.active && (isr & MPC52xx_PSC_IMR_ORERR))
  39                 psc_dma->stats.overrun_count++;
  40
  41         out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
  42
  43         return IRQ_HANDLED;
  44 }
  45
  46 /**
  47  * psc_dma_bcom_enqueue_next_buffer - Enqueue another audio buffer
  48  * @s: pointer to stream private data structure
  49  *
  50  * Enqueues another audio period buffer into the bestcomm queue.
  51  *
  52  * Note: The routine must only be called when there is space available in
  53  * the queue.  Otherwise the enqueue will fail and the audio ring buffer
  54  * will get out of sync
  55  */
  56 static void psc_dma_bcom_enqueue_next_buffer(struct psc_dma_stream *s)
  57 {
  58         struct bcom_bd *bd;
  59
  60         /* Prepare and enqueue the next buffer descriptor */
  61         bd = bcom_prepare_next_buffer(s->bcom_task);
  62         bd->status = s->period_bytes;
  63         bd->data[0] = s->runtime->dma_addr + (s->period_next * s->period_bytes);
  64         bcom_submit_next_buffer(s->bcom_task, NULL);
  65
  66         /* Update for next period */
  67         s->period_next = (s->period_next + 1) % s->runtime->periods;
  68 }
  69
  70 /* Bestcomm DMA irq handler */
  71 static irqreturn_t psc_dma_bcom_irq(int irq, void *_psc_dma_stream)
  72 {
  73         struct psc_dma_stream *s = _psc_dma_stream;
  74
  75         spin_lock(&s->psc_dma->lock);
  76         /* For each finished period, dequeue the completed period buffer
  77          * and enqueue a new one in it's place. */
  78         while (bcom_buffer_done(s->bcom_task)) {
  79                 bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
  80
  81                 s->period_current = (s->period_current+1) % s->runtime->periods;
  82                 s->period_count++;
  83
  84                 psc_dma_bcom_enqueue_next_buffer(s);
  85         }
  86         spin_unlock(&s->psc_dma->lock);
  87
  88         /* If the stream is active, then also inform the PCM middle layer
  89          * of the period finished event. */
  90         if (s->active)
  91                 snd_pcm_period_elapsed(s->stream);
  92
  93         return IRQ_HANDLED;
  94 }
  95
  96 static int psc_dma_hw_free(struct snd_pcm_substream *substream)
  97 {
  98         snd_pcm_set_runtime_buffer(substream, NULL);
  99         return 0;
 100 }
 101
 102 /**
 103  * psc_dma_trigger: start and stop the DMA transfer.
 104  *
 105  * This function is called by ALSA to start, stop, pause, and resume the DMA
 106  * transfer of data.
 107  */
 108 static int psc_dma_trigger(struct snd_pcm_substream *substream, int cmd)
 109 {
 110         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 111         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai);
 112         struct snd_pcm_runtime *runtime = substream->runtime;
 113         struct psc_dma_stream *s = to_psc_dma_stream(substream, psc_dma);
 114         struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
 115         u16 imr;
 116         unsigned long flags;
 117         int i;
 118
 119         switch (cmd) {
 120         case SNDRV_PCM_TRIGGER_START:
 121                 dev_dbg(psc_dma->dev, "START: stream=%i fbits=%u ps=%u #p=%u\n",
 122                         substream->pstr->stream, runtime->frame_bits,
 123                         (int)runtime->period_size, runtime->periods);
 124                 s->period_bytes = frames_to_bytes(runtime,
 125                                                   runtime->period_size);
 126                 s->period_next = 0;
 127                 s->period_current = 0;
 128                 s->active = 1;
 129                 s->period_count = 0;
 130                 s->runtime = runtime;
 131
 132                 /* Fill up the bestcomm bd queue and enable DMA.
 133                  * This will begin filling the PSC's fifo.
 134                  */
 135                 spin_lock_irqsave(&psc_dma->lock, flags);
 136
 137                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 138                         bcom_gen_bd_rx_reset(s->bcom_task);
 139                 else
 140                         bcom_gen_bd_tx_reset(s->bcom_task);
 141
 142                 for (i = 0; i < runtime->periods; i++)
 143                         if (!bcom_queue_full(s->bcom_task))
 144                                 psc_dma_bcom_enqueue_next_buffer(s);
 145
 146                 bcom_enable(s->bcom_task);
 147                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 148
 149                 out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
 150
 151                 break;
 152
 153         case SNDRV_PCM_TRIGGER_STOP:
 154                 dev_dbg(psc_dma->dev, "STOP: stream=%i periods_count=%i\n",
 155                         substream->pstr->stream, s->period_count);
 156                 s->active = 0;
 157
 158                 spin_lock_irqsave(&psc_dma->lock, flags);
 159                 bcom_disable(s->bcom_task);
 160                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 161                         bcom_gen_bd_rx_reset(s->bcom_task);
 162                 else
 163                         bcom_gen_bd_tx_reset(s->bcom_task);
 164                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 165
 166                 break;
 167
 168         default:
 169                 dev_dbg(psc_dma->dev, "unhandled trigger: stream=%i cmd=%i\n",
 170                         substream->pstr->stream, cmd);
 171                 return -EINVAL;
 172         }
 173
 174         /* Update interrupt enable settings */
 175         imr = 0;
 176         if (psc_dma->playback.active)
 177                 imr |= MPC52xx_PSC_IMR_TXEMP;
 178         if (psc_dma->capture.active)
 179                 imr |= MPC52xx_PSC_IMR_ORERR;
 180         out_be16(&regs->isr_imr.imr, psc_dma->imr | imr);
 181
 182         return 0;
 183 }
 184
 185
 186 /* ---------------------------------------------------------------------
 187  * The PSC DMA 'ASoC platform' driver
 188  *
 189  * Can be referenced by an 'ASoC machine' driver
 190  * This driver only deals with the audio bus; it doesn't have any
 191  * interaction with the attached codec
 192  */
 193
 194 static const struct snd_pcm_hardware psc_dma_hardware = {
 195         .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
 196                 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
 197                 SNDRV_PCM_INFO_BATCH,
 198         .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE |
 199                 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE,
 200         .rate_min = 8000,
 201         .rate_max = 48000,
 202         .channels_min = 1,
 203         .channels_max = 2,
 204         .period_bytes_max       = 1024 * 1024,
 205         .period_bytes_min       = 32,
 206         .periods_min            = 2,
 207         .periods_max            = 256,
 208         .buffer_bytes_max       = 2 * 1024 * 1024,
 209         .fifo_size              = 512,
 210 };
 211
 212 static int psc_dma_open(struct snd_pcm_substream *substream)
 213 {
 214         struct snd_pcm_runtime *runtime = substream->runtime;
 215         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 216         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai);
 217         struct psc_dma_stream *s;
 218         int rc;
 219
 220         dev_dbg(psc_dma->dev, "psc_dma_open(substream=%p)\n", substream);
 221
 222         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 223                 s = &psc_dma->capture;
 224         else
 225                 s = &psc_dma->playback;
 226
 227         snd_soc_set_runtime_hwparams(substream, &psc_dma_hardware);
 228
 229         rc = snd_pcm_hw_constraint_integer(runtime,
 230                 SNDRV_PCM_HW_PARAM_PERIODS);
 231         if (rc < 0) {
 232                 dev_err(substream->pcm->card->dev, "invalid buffer size\n");
 233                 return rc;
 234         }
 235
 236         s->stream = substream;
 237         return 0;
 238 }
 239
 240 static int psc_dma_close(struct snd_pcm_substream *substream)
 241 {
 242         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 243         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai);
 244         struct psc_dma_stream *s;
 245
 246         dev_dbg(psc_dma->dev, "psc_dma_close(substream=%p)\n", substream);
 247
 248         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 249                 s = &psc_dma->capture;
 250         else
 251                 s = &psc_dma->playback;
 252
 253         if (!psc_dma->playback.active &&
 254             !psc_dma->capture.active) {
 255
 256                 /* Disable all interrupts and reset the PSC */
 257                 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr);
 258                 out_8(&psc_dma->psc_regs->command, 4 << 4); /* reset error */
 259         }
 260         s->stream = NULL;
 261         return 0;
 262 }
 263
 264 static snd_pcm_uframes_t
 265 psc_dma_pointer(struct snd_pcm_substream *substream)
 266 {
 267         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 268         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai);
 269         struct psc_dma_stream *s;
 270         dma_addr_t count;
 271
 272         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 273                 s = &psc_dma->capture;
 274         else
 275                 s = &psc_dma->playback;
 276
 277         count = s->period_current * s->period_bytes;
 278
 279         return bytes_to_frames(substream->runtime, count);
 280 }
 281
 282 static int
 283 psc_dma_hw_params(struct snd_pcm_substream *substream,
 284                          struct snd_pcm_hw_params *params)
 285 {
 286         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 287
 288         return 0;
 289 }
 290
 291 static struct snd_pcm_ops psc_dma_ops = {
 292         .open           = psc_dma_open,
 293         .close          = psc_dma_close,
 294         .hw_free        = psc_dma_hw_free,
 295         .ioctl          = snd_pcm_lib_ioctl,
 296         .pointer        = psc_dma_pointer,
 297         .trigger        = psc_dma_trigger,
 298         .hw_params      = psc_dma_hw_params,
 299 };
 300
 301 static u64 psc_dma_dmamask = 0xffffffff;
 302 static int psc_dma_new(struct snd_soc_pcm_runtime *rtd)
 303 {
 304         struct snd_card *card = rtd->card->snd_card;
 305         struct snd_soc_dai *dai = rtd->cpu_dai;
 306         struct snd_pcm *pcm = rtd->pcm;
 307         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai);
 308         size_t size = psc_dma_hardware.buffer_bytes_max;
 309         int rc = 0;
 310
 311         dev_dbg(rtd->platform->dev, "psc_dma_new(card=%p, dai=%p, pcm=%p)\n",
 312                 card, dai, pcm);
 313
 314         if (!card->dev->dma_mask)
 315                 card->dev->dma_mask = &psc_dma_dmamask;
 316         if (!card->dev->coherent_dma_mask)
 317                 card->dev->coherent_dma_mask = 0xffffffff;
 318
 319         if (pcm->streams[0].substream) {
 320                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 321                                 size, &pcm->streams[0].substream->dma_buffer);
 322                 if (rc)
 323                         goto playback_alloc_err;
 324         }
 325
 326         if (pcm->streams[1].substream) {
 327                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 328                                 size, &pcm->streams[1].substream->dma_buffer);
 329                 if (rc)
 330                         goto capture_alloc_err;
 331         }
 332
 333         if (rtd->codec->ac97)
 334                 rtd->codec->ac97->private_data = psc_dma;
 335
 336         return 0;
 337
 338  capture_alloc_err:
 339         if (pcm->streams[0].substream)
 340                 snd_dma_free_pages(&pcm->streams[0].substream->dma_buffer);
 341
 342  playback_alloc_err:
 343         dev_err(card->dev, "Cannot allocate buffer(s)\n");
 344
 345         return -ENOMEM;
 346 }
 347
 348 static void psc_dma_free(struct snd_pcm *pcm)
 349 {
 350         struct snd_soc_pcm_runtime *rtd = pcm->private_data;
 351         struct snd_pcm_substream *substream;
 352         int stream;
 353
 354         dev_dbg(rtd->platform->dev, "psc_dma_free(pcm=%p)\n", pcm);
 355
 356         for (stream = 0; stream < 2; stream++) {
 357                 substream = pcm->streams[stream].substream;
 358                 if (substream) {
 359                         snd_dma_free_pages(&substream->dma_buffer);
 360                         substream->dma_buffer.area = NULL;
 361                         substream->dma_buffer.addr = 0;
 362                 }
 363         }
 364 }
 365
 366 static struct snd_soc_platform_driver mpc5200_audio_dma_platform = {
 367         .ops            = &psc_dma_ops,
 368         .pcm_new        = &psc_dma_new,
 369         .pcm_free       = &psc_dma_free,
 370 };
 371
 372 static int mpc5200_hpcd_probe(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, 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 snd_soc_register_platform(&op->dev, &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
 490 static int mpc5200_hpcd_remove(struct of_device *op)
 491 {
 492         struct psc_dma *psc_dma = dev_get_drvdata(&op->dev);
 493
 494         dev_dbg(&op->dev, "mpc5200_audio_dma_destroy()\n");
 495
 496         snd_soc_unregister_platform(&op->dev);
 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
 513 static struct of_device_id mpc5200_hpcd_match[] = {
 514         { .compatible = "fsl,mpc5200-pcm", },
 515         {}
 516 };
 517 MODULE_DEVICE_TABLE(of, mpc5200_hpcd_match);
 518
 519 static struct platform_driver mpc5200_hpcd_of_driver = {
 520         .probe          = mpc5200_hpcd_probe,
 521         .remove         = mpc5200_hpcd_remove,
 522         .dev = {
 523                 .owner          = THIS_MODULE,
 524                 .name           = "mpc5200-pcm-audio",
 525                 .of_match_table    = mpc5200_hpcd_match,
 526         }
 527 };
 528
 529 static int __init mpc5200_hpcd_init(void)
 530 {
 531         return platform_driver_register(&mpc5200_hpcd_of_driver);
 532 }
 533 module_init(mpc5200_hpcd_init);
 534
 535 static void __exit mpc5200_hpcd_exit(void)
 536 {
 537         platform_driver_unregister(&mpc5200_hpcd_of_driver);
 538 }
 539 module_exit(mpc5200_hpcd_exit);
 540
 541 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
 542 MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver");
 543 MODULE_LICENSE("GPL");