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->runtime->dma_addr + (s->period_next * s->period_bytes);
  62         bcom_submit_next_buffer(s->bcom_task, NULL);
  63
  64         /* Update for next period */
  65         s->period_next = (s->period_next + 1) % s->runtime->periods;
  66 }
  67
  68 /* Bestcomm DMA irq handler */
  69 static irqreturn_t psc_dma_bcom_irq(int irq, void *_psc_dma_stream)
  70 {
  71         struct psc_dma_stream *s = _psc_dma_stream;
  72
  73         spin_lock(&s->psc_dma->lock);
  74         /* For each finished period, dequeue the completed period buffer
  75          * and enqueue a new one in it's place. */
  76         while (bcom_buffer_done(s->bcom_task)) {
  77                 bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
  78
  79                 s->period_current = (s->period_current+1) % s->runtime->periods;
  80                 s->period_count++;
  81
  82                 psc_dma_bcom_enqueue_next_buffer(s);
  83         }
  84         spin_unlock(&s->psc_dma->lock);
  85
  86         /* If the stream is active, then also inform the PCM middle layer
  87          * of the period finished event. */
  88         if (s->active)
  89                 snd_pcm_period_elapsed(s->stream);
  90
  91         return IRQ_HANDLED;
  92 }
  93
  94 static int psc_dma_hw_free(struct snd_pcm_substream *substream)
  95 {
  96         snd_pcm_set_runtime_buffer(substream, NULL);
  97         return 0;
  98 }
  99
 100 /**
 101  * psc_dma_trigger: start and stop the DMA transfer.
 102  *
 103  * This function is called by ALSA to start, stop, pause, and resume the DMA
 104  * transfer of data.
 105  */
 106 static int psc_dma_trigger(struct snd_pcm_substream *substream, int cmd)
 107 {
 108         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 109         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 110         struct snd_pcm_runtime *runtime = substream->runtime;
 111         struct psc_dma_stream *s = to_psc_dma_stream(substream, psc_dma);
 112         struct mpc52xx_psc __iomem *regs = psc_dma->psc_regs;
 113         u16 imr;
 114         unsigned long flags;
 115         int i;
 116
 117         switch (cmd) {
 118         case SNDRV_PCM_TRIGGER_START:
 119                 dev_dbg(psc_dma->dev, "START: stream=%i fbits=%u ps=%u #p=%u\n",
 120                         substream->pstr->stream, runtime->frame_bits,
 121                         (int)runtime->period_size, runtime->periods);
 122                 s->period_bytes = frames_to_bytes(runtime,
 123                                                   runtime->period_size);
 124                 s->period_next = 0;
 125                 s->period_current = 0;
 126                 s->active = 1;
 127                 s->period_count = 0;
 128                 s->runtime = runtime;
 129
 130                 /* Fill up the bestcomm bd queue and enable DMA.
 131                  * This will begin filling the PSC's fifo.
 132                  */
 133                 spin_lock_irqsave(&psc_dma->lock, flags);
 134
 135                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 136                         bcom_gen_bd_rx_reset(s->bcom_task);
 137                 else
 138                         bcom_gen_bd_tx_reset(s->bcom_task);
 139
 140                 for (i = 0; i < runtime->periods; i++)
 141                         if (!bcom_queue_full(s->bcom_task))
 142                                 psc_dma_bcom_enqueue_next_buffer(s);
 143
 144                 bcom_enable(s->bcom_task);
 145                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 146
 147                 out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
 148
 149                 break;
 150
 151         case SNDRV_PCM_TRIGGER_STOP:
 152                 dev_dbg(psc_dma->dev, "STOP: stream=%i periods_count=%i\n",
 153                         substream->pstr->stream, s->period_count);
 154                 s->active = 0;
 155
 156                 spin_lock_irqsave(&psc_dma->lock, flags);
 157                 bcom_disable(s->bcom_task);
 158                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 159                         bcom_gen_bd_rx_reset(s->bcom_task);
 160                 else
 161                         bcom_gen_bd_tx_reset(s->bcom_task);
 162                 spin_unlock_irqrestore(&psc_dma->lock, flags);
 163
 164                 break;
 165
 166         default:
 167                 dev_dbg(psc_dma->dev, "unhandled trigger: stream=%i cmd=%i\n",
 168                         substream->pstr->stream, cmd);
 169                 return -EINVAL;
 170         }
 171
 172         /* Update interrupt enable settings */
 173         imr = 0;
 174         if (psc_dma->playback.active)
 175                 imr |= MPC52xx_PSC_IMR_TXEMP;
 176         if (psc_dma->capture.active)
 177                 imr |= MPC52xx_PSC_IMR_ORERR;
 178         out_be16(&regs->isr_imr.imr, psc_dma->imr | imr);
 179
 180         return 0;
 181 }
 182
 183
 184 /* ---------------------------------------------------------------------
 185  * The PSC DMA 'ASoC platform' driver
 186  *
 187  * Can be referenced by an 'ASoC machine' driver
 188  * This driver only deals with the audio bus; it doesn't have any
 189  * interaction with the attached codec
 190  */
 191
 192 static const struct snd_pcm_hardware psc_dma_hardware = {
 193         .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
 194                 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
 195                 SNDRV_PCM_INFO_BATCH,
 196         .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE |
 197                 SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE,
 198         .rate_min = 8000,
 199         .rate_max = 48000,
 200         .channels_min = 1,
 201         .channels_max = 2,
 202         .period_bytes_max       = 1024 * 1024,
 203         .period_bytes_min       = 32,
 204         .periods_min            = 2,
 205         .periods_max            = 256,
 206         .buffer_bytes_max       = 2 * 1024 * 1024,
 207         .fifo_size              = 512,
 208 };
 209
 210 static int psc_dma_open(struct snd_pcm_substream *substream)
 211 {
 212         struct snd_pcm_runtime *runtime = substream->runtime;
 213         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 214         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 215         struct psc_dma_stream *s;
 216         int rc;
 217
 218         dev_dbg(psc_dma->dev, "psc_dma_open(substream=%p)\n", substream);
 219
 220         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 221                 s = &psc_dma->capture;
 222         else
 223                 s = &psc_dma->playback;
 224
 225         snd_soc_set_runtime_hwparams(substream, &psc_dma_hardware);
 226
 227         rc = snd_pcm_hw_constraint_integer(runtime,
 228                 SNDRV_PCM_HW_PARAM_PERIODS);
 229         if (rc < 0) {
 230                 dev_err(substream->pcm->card->dev, "invalid buffer size\n");
 231                 return rc;
 232         }
 233
 234         s->stream = substream;
 235         return 0;
 236 }
 237
 238 static int psc_dma_close(struct snd_pcm_substream *substream)
 239 {
 240         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 241         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 242         struct psc_dma_stream *s;
 243
 244         dev_dbg(psc_dma->dev, "psc_dma_close(substream=%p)\n", substream);
 245
 246         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 247                 s = &psc_dma->capture;
 248         else
 249                 s = &psc_dma->playback;
 250
 251         if (!psc_dma->playback.active &&
 252             !psc_dma->capture.active) {
 253
 254                 /* Disable all interrupts and reset the PSC */
 255                 out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr);
 256                 out_8(&psc_dma->psc_regs->command, 4 << 4); /* reset error */
 257         }
 258         s->stream = NULL;
 259         return 0;
 260 }
 261
 262 static snd_pcm_uframes_t
 263 psc_dma_pointer(struct snd_pcm_substream *substream)
 264 {
 265         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 266         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 267         struct psc_dma_stream *s;
 268         dma_addr_t count;
 269
 270         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 271                 s = &psc_dma->capture;
 272         else
 273                 s = &psc_dma->playback;
 274
 275         count = s->period_current * s->period_bytes;
 276
 277         return bytes_to_frames(substream->runtime, count);
 278 }
 279
 280 static int
 281 psc_dma_hw_params(struct snd_pcm_substream *substream,
 282                          struct snd_pcm_hw_params *params)
 283 {
 284         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 285
 286         return 0;
 287 }
 288
 289 static struct snd_pcm_ops psc_dma_ops = {
 290         .open           = psc_dma_open,
 291         .close          = psc_dma_close,
 292         .hw_free        = psc_dma_hw_free,
 293         .ioctl          = snd_pcm_lib_ioctl,
 294         .pointer        = psc_dma_pointer,
 295         .trigger        = psc_dma_trigger,
 296         .hw_params      = psc_dma_hw_params,
 297 };
 298
 299 static u64 psc_dma_dmamask = 0xffffffff;
 300 static int psc_dma_new(struct snd_card *card, struct snd_soc_dai *dai,
 301                            struct snd_pcm *pcm)
 302 {
 303         struct snd_soc_pcm_runtime *rtd = pcm->private_data;
 304         struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
 305         size_t size = psc_dma_hardware.buffer_bytes_max;
 306         int rc = 0;
 307
 308         dev_dbg(rtd->socdev->dev, "psc_dma_new(card=%p, dai=%p, pcm=%p)\n",
 309                 card, dai, pcm);
 310
 311         if (!card->dev->dma_mask)
 312                 card->dev->dma_mask = &psc_dma_dmamask;
 313         if (!card->dev->coherent_dma_mask)
 314                 card->dev->coherent_dma_mask = 0xffffffff;
 315
 316         if (pcm->streams[0].substream) {
 317                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 318                                 size, &pcm->streams[0].substream->dma_buffer);
 319                 if (rc)
 320                         goto playback_alloc_err;
 321         }
 322
 323         if (pcm->streams[1].substream) {
 324                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->card->dev,
 325                                 size, &pcm->streams[1].substream->dma_buffer);
 326                 if (rc)
 327                         goto capture_alloc_err;
 328         }
 329
 330         if (rtd->socdev->card->codec->ac97)
 331                 rtd->socdev->card->codec->ac97->private_data = psc_dma;
 332
 333         return 0;
 334
 335  capture_alloc_err:
 336         if (pcm->streams[0].substream)
 337                 snd_dma_free_pages(&pcm->streams[0].substream->dma_buffer);
 338
 339  playback_alloc_err:
 340         dev_err(card->dev, "Cannot allocate buffer(s)\n");
 341
 342         return -ENOMEM;
 343 }
 344
 345 static void psc_dma_free(struct snd_pcm *pcm)
 346 {
 347         struct snd_soc_pcm_runtime *rtd = pcm->private_data;
 348         struct snd_pcm_substream *substream;
 349         int stream;
 350
 351         dev_dbg(rtd->socdev->dev, "psc_dma_free(pcm=%p)\n", pcm);
 352
 353         for (stream = 0; stream < 2; stream++) {
 354                 substream = pcm->streams[stream].substream;
 355                 if (substream) {
 356                         snd_dma_free_pages(&substream->dma_buffer);
 357                         substream->dma_buffer.area = NULL;
 358                         substream->dma_buffer.addr = 0;
 359                 }
 360         }
 361 }
 362
 363 struct snd_soc_platform mpc5200_audio_dma_platform = {
 364         .name           = "mpc5200-psc-audio",
 365         .pcm_ops        = &psc_dma_ops,
 366         .pcm_new        = &psc_dma_new,
 367         .pcm_free       = &psc_dma_free,
 368 };
 369 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_platform);
 370
 371 int mpc5200_audio_dma_create(struct of_device *op)
 372 {
 373         phys_addr_t fifo;
 374         struct psc_dma *psc_dma;
 375         struct resource res;
 376         int size, irq, rc;
 377         const __be32 *prop;
 378         void __iomem *regs;
 379         int ret;
 380
 381         /* Fetch the registers and IRQ of the PSC */
 382         irq = irq_of_parse_and_map(op->node, 0);
 383         if (of_address_to_resource(op->node, 0, &res)) {
 384                 dev_err(&op->dev, "Missing reg property\n");
 385                 return -ENODEV;
 386         }
 387         regs = ioremap(res.start, 1 + res.end - res.start);
 388         if (!regs) {
 389                 dev_err(&op->dev, "Could not map registers\n");
 390                 return -ENODEV;
 391         }
 392
 393         /* Allocate and initialize the driver private data */
 394         psc_dma = kzalloc(sizeof *psc_dma, GFP_KERNEL);
 395         if (!psc_dma) {
 396                 ret = -ENOMEM;
 397                 goto out_unmap;
 398         }
 399
 400         /* Get the PSC ID */
 401         prop = of_get_property(op->node, "cell-index", &size);
 402         if (!prop || size < sizeof *prop) {
 403                 ret = -ENODEV;
 404                 goto out_free;
 405         }
 406
 407         spin_lock_init(&psc_dma->lock);
 408         mutex_init(&psc_dma->mutex);
 409         psc_dma->id = be32_to_cpu(*prop);
 410         psc_dma->irq = irq;
 411         psc_dma->psc_regs = regs;
 412         psc_dma->fifo_regs = regs + sizeof *psc_dma->psc_regs;
 413         psc_dma->dev = &op->dev;
 414         psc_dma->playback.psc_dma = psc_dma;
 415         psc_dma->capture.psc_dma = psc_dma;
 416         snprintf(psc_dma->name, sizeof psc_dma->name, "PSC%u", psc_dma->id);
 417
 418         /* Find the address of the fifo data registers and setup the
 419          * DMA tasks */
 420         fifo = res.start + offsetof(struct mpc52xx_psc, buffer.buffer_32);
 421         psc_dma->capture.bcom_task =
 422                 bcom_psc_gen_bd_rx_init(psc_dma->id, 10, fifo, 512);
 423         psc_dma->playback.bcom_task =
 424                 bcom_psc_gen_bd_tx_init(psc_dma->id, 10, fifo);
 425         if (!psc_dma->capture.bcom_task ||
 426             !psc_dma->playback.bcom_task) {
 427                 dev_err(&op->dev, "Could not allocate bestcomm tasks\n");
 428                 ret = -ENODEV;
 429                 goto out_free;
 430         }
 431
 432         /* Disable all interrupts and reset the PSC */
 433         out_be16(&psc_dma->psc_regs->isr_imr.imr, psc_dma->imr);
 434          /* reset receiver */
 435         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_RX);
 436          /* reset transmitter */
 437         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_TX);
 438          /* reset error */
 439         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_RST_ERR_STAT);
 440          /* reset mode */
 441         out_8(&psc_dma->psc_regs->command, MPC52xx_PSC_SEL_MODE_REG_1);
 442
 443         /* Set up mode register;
 444          * First write: RxRdy (FIFO Alarm) generates rx FIFO irq
 445          * Second write: register Normal mode for non loopback
 446          */
 447         out_8(&psc_dma->psc_regs->mode, 0);
 448         out_8(&psc_dma->psc_regs->mode, 0);
 449
 450         /* Set the TX and RX fifo alarm thresholds */
 451         out_be16(&psc_dma->fifo_regs->rfalarm, 0x100);
 452         out_8(&psc_dma->fifo_regs->rfcntl, 0x4);
 453         out_be16(&psc_dma->fifo_regs->tfalarm, 0x100);
 454         out_8(&psc_dma->fifo_regs->tfcntl, 0x7);
 455
 456         /* Lookup the IRQ numbers */
 457         psc_dma->playback.irq =
 458                 bcom_get_task_irq(psc_dma->playback.bcom_task);
 459         psc_dma->capture.irq =
 460                 bcom_get_task_irq(psc_dma->capture.bcom_task);
 461
 462         rc = request_irq(psc_dma->irq, &psc_dma_status_irq, IRQF_SHARED,
 463                          "psc-dma-status", psc_dma);
 464         rc |= request_irq(psc_dma->capture.irq, &psc_dma_bcom_irq, IRQF_SHARED,
 465                           "psc-dma-capture", &psc_dma->capture);
 466         rc |= request_irq(psc_dma->playback.irq, &psc_dma_bcom_irq, IRQF_SHARED,
 467                           "psc-dma-playback", &psc_dma->playback);
 468         if (rc) {
 469                 ret = -ENODEV;
 470                 goto out_irq;
 471         }
 472
 473         /* Save what we've done so it can be found again later */
 474         dev_set_drvdata(&op->dev, psc_dma);
 475
 476         /* Tell the ASoC OF helpers about it */
 477         return snd_soc_register_platform(&mpc5200_audio_dma_platform);
 478 out_irq:
 479         free_irq(psc_dma->irq, psc_dma);
 480         free_irq(psc_dma->capture.irq, &psc_dma->capture);
 481         free_irq(psc_dma->playback.irq, &psc_dma->playback);
 482 out_free:
 483         kfree(psc_dma);
 484 out_unmap:
 485         iounmap(regs);
 486         return ret;
 487 }
 488 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_create);
 489
 490 int mpc5200_audio_dma_destroy(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(&mpc5200_audio_dma_platform);
 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 EXPORT_SYMBOL_GPL(mpc5200_audio_dma_destroy);
 513
 514 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
 515 MODULE_DESCRIPTION("Freescale MPC5200 PSC in DMA mode ASoC Driver");
 516 MODULE_LICENSE("GPL");