sound/soc/fsl/mpc5200_psc_i2s.c

   1 /*
   2  * Freescale MPC5200 PSC in I2S mode
   3  * ALSA SoC Digital Audio Interface (DAI) driver
   4  *
   5  * Copyright (C) 2008 Secret Lab Technologies Ltd.
   6  */
   7
   8 #include <linux/init.h>
   9 #include <linux/module.h>
  10 #include <linux/interrupt.h>
  11 #include <linux/device.h>
  12 #include <linux/delay.h>
  13 #include <linux/of_device.h>
  14 #include <linux/of_platform.h>
  15 #include <linux/dma-mapping.h>
  16
  17 #include <sound/core.h>
  18 #include <sound/pcm.h>
  19 #include <sound/pcm_params.h>
  20 #include <sound/initval.h>
  21 #include <sound/soc.h>
  22 #include <sound/soc-of-simple.h>
  23
  24 #include <sysdev/bestcomm/bestcomm.h>
  25 #include <sysdev/bestcomm/gen_bd.h>
  26 #include <asm/mpc52xx_psc.h>
  27
  28 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
  29 MODULE_DESCRIPTION("Freescale MPC5200 PSC in I2S mode ASoC Driver");
  30 MODULE_LICENSE("GPL");
  31
  32 /**
  33  * PSC_I2S_RATES: sample rates supported by the I2S
  34  *
  35  * This driver currently only supports the PSC running in I2S slave mode,
  36  * which means the codec determines the sample rate.  Therefore, we tell
  37  * ALSA that we support all rates and let the codec driver decide what rates
  38  * are really supported.
  39  */
  40 #define PSC_I2S_RATES (SNDRV_PCM_RATE_5512 | SNDRV_PCM_RATE_8000_192000 | \
  41                         SNDRV_PCM_RATE_CONTINUOUS)
  42
  43 /**
  44  * PSC_I2S_FORMATS: audio formats supported by the PSC I2S mode
  45  */
  46 #define PSC_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | \
  47                          SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S24_BE | \
  48                          SNDRV_PCM_FMTBIT_S32_BE)
  49
  50 /**
  51  * psc_i2s_stream - Data specific to a single stream (playback or capture)
  52  * @active:             flag indicating if the stream is active
  53  * @psc_i2s:            pointer back to parent psc_i2s data structure
  54  * @bcom_task:          bestcomm task structure
  55  * @irq:                irq number for bestcomm task
  56  * @period_start:       physical address of start of DMA region
  57  * @period_end:         physical address of end of DMA region
  58  * @period_next_pt:     physical address of next DMA buffer to enqueue
  59  * @period_bytes:       size of DMA period in bytes
  60  */
  61 struct psc_i2s_stream {
  62         int active;
  63         struct psc_i2s *psc_i2s;
  64         struct bcom_task *bcom_task;
  65         int irq;
  66         struct snd_pcm_substream *stream;
  67         dma_addr_t period_start;
  68         dma_addr_t period_end;
  69         dma_addr_t period_next_pt;
  70         dma_addr_t period_current_pt;
  71         int period_bytes;
  72 };
  73
  74 /**
  75  * psc_i2s - Private driver data
  76  * @name: short name for this device ("PSC0", "PSC1", etc)
  77  * @psc_regs: pointer to the PSC's registers
  78  * @fifo_regs: pointer to the PSC's FIFO registers
  79  * @irq: IRQ of this PSC
  80  * @dev: struct device pointer
  81  * @dai: the CPU DAI for this device
  82  * @sicr: Base value used in serial interface control register; mode is ORed
  83  *        with this value.
  84  * @playback: Playback stream context data
  85  * @capture: Capture stream context data
  86  */
  87 struct psc_i2s {
  88         char name[32];
  89         struct mpc52xx_psc __iomem *psc_regs;
  90         struct mpc52xx_psc_fifo __iomem *fifo_regs;
  91         unsigned int irq;
  92         struct device *dev;
  93         struct snd_soc_dai dai;
  94         spinlock_t lock;
  95         u32 sicr;
  96
  97         /* per-stream data */
  98         struct psc_i2s_stream playback;
  99         struct psc_i2s_stream capture;
 100
 101         /* Statistics */
 102         struct {
 103                 int overrun_count;
 104                 int underrun_count;
 105         } stats;
 106 };
 107
 108 /*
 109  * Interrupt handlers
 110  */
 111 static irqreturn_t psc_i2s_status_irq(int irq, void *_psc_i2s)
 112 {
 113         struct psc_i2s *psc_i2s = _psc_i2s;
 114         struct mpc52xx_psc __iomem *regs = psc_i2s->psc_regs;
 115         u16 isr;
 116
 117         isr = in_be16(&regs->mpc52xx_psc_isr);
 118
 119         /* Playback underrun error */
 120         if (psc_i2s->playback.active && (isr & MPC52xx_PSC_IMR_TXEMP))
 121                 psc_i2s->stats.underrun_count++;
 122
 123         /* Capture overrun error */
 124         if (psc_i2s->capture.active && (isr & MPC52xx_PSC_IMR_ORERR))
 125                 psc_i2s->stats.overrun_count++;
 126
 127         out_8(&regs->command, 4 << 4);  /* reset the error status */
 128
 129         return IRQ_HANDLED;
 130 }
 131
 132 /**
 133  * psc_i2s_bcom_enqueue_next_buffer - Enqueue another audio buffer
 134  * @s: pointer to stream private data structure
 135  *
 136  * Enqueues another audio period buffer into the bestcomm queue.
 137  *
 138  * Note: The routine must only be called when there is space available in
 139  * the queue.  Otherwise the enqueue will fail and the audio ring buffer
 140  * will get out of sync
 141  */
 142 static void psc_i2s_bcom_enqueue_next_buffer(struct psc_i2s_stream *s)
 143 {
 144         struct bcom_bd *bd;
 145
 146         /* Prepare and enqueue the next buffer descriptor */
 147         bd = bcom_prepare_next_buffer(s->bcom_task);
 148         bd->status = s->period_bytes;
 149         bd->data[0] = s->period_next_pt;
 150         bcom_submit_next_buffer(s->bcom_task, NULL);
 151
 152         /* Update for next period */
 153         s->period_next_pt += s->period_bytes;
 154         if (s->period_next_pt >= s->period_end)
 155                 s->period_next_pt = s->period_start;
 156 }
 157
 158 /* Bestcomm DMA irq handler */
 159 static irqreturn_t psc_i2s_bcom_irq(int irq, void *_psc_i2s_stream)
 160 {
 161         struct psc_i2s_stream *s = _psc_i2s_stream;
 162
 163         /* For each finished period, dequeue the completed period buffer
 164          * and enqueue a new one in it's place. */
 165         while (bcom_buffer_done(s->bcom_task)) {
 166                 bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
 167                 s->period_current_pt += s->period_bytes;
 168                 if (s->period_current_pt >= s->period_end)
 169                         s->period_current_pt = s->period_start;
 170                 psc_i2s_bcom_enqueue_next_buffer(s);
 171                 bcom_enable(s->bcom_task);
 172         }
 173
 174         /* If the stream is active, then also inform the PCM middle layer
 175          * of the period finished event. */
 176         if (s->active)
 177                 snd_pcm_period_elapsed(s->stream);
 178
 179         return IRQ_HANDLED;
 180 }
 181
 182 /**
 183  * psc_i2s_startup: create a new substream
 184  *
 185  * This is the first function called when a stream is opened.
 186  *
 187  * If this is the first stream open, then grab the IRQ and program most of
 188  * the PSC registers.
 189  */
 190 static int psc_i2s_startup(struct snd_pcm_substream *substream,
 191                            struct snd_soc_dai *dai)
 192 {
 193         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 194         struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
 195         int rc;
 196
 197         dev_dbg(psc_i2s->dev, "psc_i2s_startup(substream=%p)\n", substream);
 198
 199         if (!psc_i2s->playback.active &&
 200             !psc_i2s->capture.active) {
 201                 /* Setup the IRQs */
 202                 rc = request_irq(psc_i2s->irq, &psc_i2s_status_irq, IRQF_SHARED,
 203                                  "psc-i2s-status", psc_i2s);
 204                 rc |= request_irq(psc_i2s->capture.irq,
 205                                   &psc_i2s_bcom_irq, IRQF_SHARED,
 206                                   "psc-i2s-capture", &psc_i2s->capture);
 207                 rc |= request_irq(psc_i2s->playback.irq,
 208                                   &psc_i2s_bcom_irq, IRQF_SHARED,
 209                                   "psc-i2s-playback", &psc_i2s->playback);
 210                 if (rc) {
 211                         free_irq(psc_i2s->irq, psc_i2s);
 212                         free_irq(psc_i2s->capture.irq,
 213                                  &psc_i2s->capture);
 214                         free_irq(psc_i2s->playback.irq,
 215                                  &psc_i2s->playback);
 216                         return -ENODEV;
 217                 }
 218         }
 219
 220         return 0;
 221 }
 222
 223 static int psc_i2s_hw_params(struct snd_pcm_substream *substream,
 224                                  struct snd_pcm_hw_params *params,
 225                                  struct snd_soc_dai *dai)
 226 {
 227         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 228         struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
 229         u32 mode;
 230
 231         dev_dbg(psc_i2s->dev, "%s(substream=%p) p_size=%i p_bytes=%i"
 232                 " periods=%i buffer_size=%i  buffer_bytes=%i\n",
 233                 __func__, substream, params_period_size(params),
 234                 params_period_bytes(params), params_periods(params),
 235                 params_buffer_size(params), params_buffer_bytes(params));
 236
 237         switch (params_format(params)) {
 238         case SNDRV_PCM_FORMAT_S8:
 239                 mode = MPC52xx_PSC_SICR_SIM_CODEC_8;
 240                 break;
 241         case SNDRV_PCM_FORMAT_S16_BE:
 242                 mode = MPC52xx_PSC_SICR_SIM_CODEC_16;
 243                 break;
 244         case SNDRV_PCM_FORMAT_S24_BE:
 245                 mode = MPC52xx_PSC_SICR_SIM_CODEC_24;
 246                 break;
 247         case SNDRV_PCM_FORMAT_S32_BE:
 248                 mode = MPC52xx_PSC_SICR_SIM_CODEC_32;
 249                 break;
 250         default:
 251                 dev_dbg(psc_i2s->dev, "invalid format\n");
 252                 return -EINVAL;
 253         }
 254         out_be32(&psc_i2s->psc_regs->sicr, psc_i2s->sicr | mode);
 255
 256         snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
 257
 258         return 0;
 259 }
 260
 261 static int psc_i2s_hw_free(struct snd_pcm_substream *substream,
 262                            struct snd_soc_dai *dai)
 263 {
 264         snd_pcm_set_runtime_buffer(substream, NULL);
 265         return 0;
 266 }
 267
 268 /**
 269  * psc_i2s_trigger: start and stop the DMA transfer.
 270  *
 271  * This function is called by ALSA to start, stop, pause, and resume the DMA
 272  * transfer of data.
 273  */
 274 static int psc_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
 275                            struct snd_soc_dai *dai)
 276 {
 277         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 278         struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
 279         struct snd_pcm_runtime *runtime = substream->runtime;
 280         struct psc_i2s_stream *s;
 281         struct mpc52xx_psc __iomem *regs = psc_i2s->psc_regs;
 282         u16 imr;
 283         u8 psc_cmd;
 284         unsigned long flags;
 285
 286         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 287                 s = &psc_i2s->capture;
 288         else
 289                 s = &psc_i2s->playback;
 290
 291         dev_dbg(psc_i2s->dev, "psc_i2s_trigger(substream=%p, cmd=%i)"
 292                 " stream_id=%i\n",
 293                 substream, cmd, substream->pstr->stream);
 294
 295         switch (cmd) {
 296         case SNDRV_PCM_TRIGGER_START:
 297                 s->period_bytes = frames_to_bytes(runtime,
 298                                                   runtime->period_size);
 299                 s->period_start = virt_to_phys(runtime->dma_area);
 300                 s->period_end = s->period_start +
 301                                 (s->period_bytes * runtime->periods);
 302                 s->period_next_pt = s->period_start;
 303                 s->period_current_pt = s->period_start;
 304                 s->active = 1;
 305
 306                 /* First; reset everything */
 307                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) {
 308                         out_8(&regs->command, MPC52xx_PSC_RST_RX);
 309                         out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
 310                 } else {
 311                         out_8(&regs->command, MPC52xx_PSC_RST_TX);
 312                         out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
 313                 }
 314
 315                 /* Next, fill up the bestcomm bd queue and enable DMA.
 316                  * This will begin filling the PSC's fifo. */
 317                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 318                         bcom_gen_bd_rx_reset(s->bcom_task);
 319                 else
 320                         bcom_gen_bd_tx_reset(s->bcom_task);
 321                 while (!bcom_queue_full(s->bcom_task))
 322                         psc_i2s_bcom_enqueue_next_buffer(s);
 323                 bcom_enable(s->bcom_task);
 324
 325                 /* Due to errata in the i2s mode; need to line up enabling
 326                  * the transmitter with a transition on the frame sync
 327                  * line */
 328
 329                 spin_lock_irqsave(&psc_i2s->lock, flags);
 330                 /* first make sure it is low */
 331                 while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) != 0)
 332                         ;
 333                 /* then wait for the transition to high */
 334                 while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) == 0)
 335                         ;
 336                 /* Finally, enable the PSC.
 337                  * Receiver must always be enabled; even when we only want
 338                  * transmit.  (see 15.3.2.3 of MPC5200B User's Guide) */
 339                 psc_cmd = MPC52xx_PSC_RX_ENABLE;
 340                 if (substream->pstr->stream == SNDRV_PCM_STREAM_PLAYBACK)
 341                         psc_cmd |= MPC52xx_PSC_TX_ENABLE;
 342                 out_8(&regs->command, psc_cmd);
 343                 spin_unlock_irqrestore(&psc_i2s->lock, flags);
 344
 345                 break;
 346
 347         case SNDRV_PCM_TRIGGER_STOP:
 348                 /* Turn off the PSC */
 349                 s->active = 0;
 350                 if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) {
 351                         if (!psc_i2s->playback.active) {
 352                                 out_8(&regs->command, 2 << 4);  /* reset rx */
 353                                 out_8(&regs->command, 3 << 4);  /* reset tx */
 354                                 out_8(&regs->command, 4 << 4);  /* reset err */
 355                         }
 356                 } else {
 357                         out_8(&regs->command, 3 << 4);  /* reset tx */
 358                         out_8(&regs->command, 4 << 4);  /* reset err */
 359                         if (!psc_i2s->capture.active)
 360                                 out_8(&regs->command, 2 << 4);  /* reset rx */
 361                 }
 362
 363                 bcom_disable(s->bcom_task);
 364                 while (!bcom_queue_empty(s->bcom_task))
 365                         bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
 366
 367                 break;
 368
 369         default:
 370                 dev_dbg(psc_i2s->dev, "invalid command\n");
 371                 return -EINVAL;
 372         }
 373
 374         /* Update interrupt enable settings */
 375         imr = 0;
 376         if (psc_i2s->playback.active)
 377                 imr |= MPC52xx_PSC_IMR_TXEMP;
 378         if (psc_i2s->capture.active)
 379                 imr |= MPC52xx_PSC_IMR_ORERR;
 380         out_be16(&regs->isr_imr.imr, imr);
 381
 382         return 0;
 383 }
 384
 385 /**
 386  * psc_i2s_shutdown: shutdown the data transfer on a stream
 387  *
 388  * Shutdown the PSC if there are no other substreams open.
 389  */
 390 static void psc_i2s_shutdown(struct snd_pcm_substream *substream,
 391                              struct snd_soc_dai *dai)
 392 {
 393         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 394         struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
 395
 396         dev_dbg(psc_i2s->dev, "psc_i2s_shutdown(substream=%p)\n", substream);
 397
 398         /*
 399          * If this is the last active substream, disable the PSC and release
 400          * the IRQ.
 401          */
 402         if (!psc_i2s->playback.active &&
 403             !psc_i2s->capture.active) {
 404
 405                 /* Disable all interrupts and reset the PSC */
 406                 out_be16(&psc_i2s->psc_regs->isr_imr.imr, 0);
 407                 out_8(&psc_i2s->psc_regs->command, 3 << 4); /* reset tx */
 408                 out_8(&psc_i2s->psc_regs->command, 2 << 4); /* reset rx */
 409                 out_8(&psc_i2s->psc_regs->command, 1 << 4); /* reset mode */
 410                 out_8(&psc_i2s->psc_regs->command, 4 << 4); /* reset error */
 411
 412                 /* Release irqs */
 413                 free_irq(psc_i2s->irq, psc_i2s);
 414                 free_irq(psc_i2s->capture.irq, &psc_i2s->capture);
 415                 free_irq(psc_i2s->playback.irq, &psc_i2s->playback);
 416         }
 417 }
 418
 419 /**
 420  * psc_i2s_set_sysclk: set the clock frequency and direction
 421  *
 422  * This function is called by the machine driver to tell us what the clock
 423  * frequency and direction are.
 424  *
 425  * Currently, we only support operating as a clock slave (SND_SOC_CLOCK_IN),
 426  * and we don't care about the frequency.  Return an error if the direction
 427  * is not SND_SOC_CLOCK_IN.
 428  *
 429  * @clk_id: reserved, should be zero
 430  * @freq: the frequency of the given clock ID, currently ignored
 431  * @dir: SND_SOC_CLOCK_IN (clock slave) or SND_SOC_CLOCK_OUT (clock master)
 432  */
 433 static int psc_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
 434                               int clk_id, unsigned int freq, int dir)
 435 {
 436         struct psc_i2s *psc_i2s = cpu_dai->private_data;
 437         dev_dbg(psc_i2s->dev, "psc_i2s_set_sysclk(cpu_dai=%p, dir=%i)\n",
 438                                 cpu_dai, dir);
 439         return (dir == SND_SOC_CLOCK_IN) ? 0 : -EINVAL;
 440 }
 441
 442 /**
 443  * psc_i2s_set_fmt: set the serial format.
 444  *
 445  * This function is called by the machine driver to tell us what serial
 446  * format to use.
 447  *
 448  * This driver only supports I2S mode.  Return an error if the format is
 449  * not SND_SOC_DAIFMT_I2S.
 450  *
 451  * @format: one of SND_SOC_DAIFMT_xxx
 452  */
 453 static int psc_i2s_set_fmt(struct snd_soc_dai *cpu_dai, unsigned int format)
 454 {
 455         struct psc_i2s *psc_i2s = cpu_dai->private_data;
 456         dev_dbg(psc_i2s->dev, "psc_i2s_set_fmt(cpu_dai=%p, format=%i)\n",
 457                                 cpu_dai, format);
 458         return (format == SND_SOC_DAIFMT_I2S) ? 0 : -EINVAL;
 459 }
 460
 461 /* ---------------------------------------------------------------------
 462  * ALSA SoC Bindings
 463  *
 464  * - Digital Audio Interface (DAI) template
 465  * - create/destroy dai hooks
 466  */
 467
 468 /**
 469  * psc_i2s_dai_template: template CPU Digital Audio Interface
 470  */
 471 static struct snd_soc_dai_ops psc_i2s_dai_ops = {
 472         .startup        = psc_i2s_startup,
 473         .hw_params      = psc_i2s_hw_params,
 474         .hw_free        = psc_i2s_hw_free,
 475         .shutdown       = psc_i2s_shutdown,
 476         .trigger        = psc_i2s_trigger,
 477         .set_sysclk     = psc_i2s_set_sysclk,
 478         .set_fmt        = psc_i2s_set_fmt,
 479 };
 480
 481 static struct snd_soc_dai psc_i2s_dai_template = {
 482         .playback = {
 483                 .channels_min = 2,
 484                 .channels_max = 2,
 485                 .rates = PSC_I2S_RATES,
 486                 .formats = PSC_I2S_FORMATS,
 487         },
 488         .capture = {
 489                 .channels_min = 2,
 490                 .channels_max = 2,
 491                 .rates = PSC_I2S_RATES,
 492                 .formats = PSC_I2S_FORMATS,
 493         },
 494         .ops = &psc_i2s_dai_ops,
 495 };
 496
 497 /* ---------------------------------------------------------------------
 498  * The PSC I2S 'ASoC platform' driver
 499  *
 500  * Can be referenced by an 'ASoC machine' driver
 501  * This driver only deals with the audio bus; it doesn't have any
 502  * interaction with the attached codec
 503  */
 504
 505 static const struct snd_pcm_hardware psc_i2s_pcm_hardware = {
 506         .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
 507                 SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER,
 508         .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE |
 509                    SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE,
 510         .rate_min = 8000,
 511         .rate_max = 48000,
 512         .channels_min = 2,
 513         .channels_max = 2,
 514         .period_bytes_max       = 1024 * 1024,
 515         .period_bytes_min       = 32,
 516         .periods_min            = 2,
 517         .periods_max            = 256,
 518         .buffer_bytes_max       = 2 * 1024 * 1024,
 519         .fifo_size              = 0,
 520 };
 521
 522 static int psc_i2s_pcm_open(struct snd_pcm_substream *substream)
 523 {
 524         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 525         struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
 526         struct psc_i2s_stream *s;
 527
 528         dev_dbg(psc_i2s->dev, "psc_i2s_pcm_open(substream=%p)\n", substream);
 529
 530         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 531                 s = &psc_i2s->capture;
 532         else
 533                 s = &psc_i2s->playback;
 534
 535         snd_soc_set_runtime_hwparams(substream, &psc_i2s_pcm_hardware);
 536
 537         s->stream = substream;
 538         return 0;
 539 }
 540
 541 static int psc_i2s_pcm_close(struct snd_pcm_substream *substream)
 542 {
 543         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 544         struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
 545         struct psc_i2s_stream *s;
 546
 547         dev_dbg(psc_i2s->dev, "psc_i2s_pcm_close(substream=%p)\n", substream);
 548
 549         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 550                 s = &psc_i2s->capture;
 551         else
 552                 s = &psc_i2s->playback;
 553
 554         s->stream = NULL;
 555         return 0;
 556 }
 557
 558 static snd_pcm_uframes_t
 559 psc_i2s_pcm_pointer(struct snd_pcm_substream *substream)
 560 {
 561         struct snd_soc_pcm_runtime *rtd = substream->private_data;
 562         struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
 563         struct psc_i2s_stream *s;
 564         dma_addr_t count;
 565
 566         if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
 567                 s = &psc_i2s->capture;
 568         else
 569                 s = &psc_i2s->playback;
 570
 571         count = s->period_current_pt - s->period_start;
 572
 573         return bytes_to_frames(substream->runtime, count);
 574 }
 575
 576 static struct snd_pcm_ops psc_i2s_pcm_ops = {
 577         .open           = psc_i2s_pcm_open,
 578         .close          = psc_i2s_pcm_close,
 579         .ioctl          = snd_pcm_lib_ioctl,
 580         .pointer        = psc_i2s_pcm_pointer,
 581 };
 582
 583 static u64 psc_i2s_pcm_dmamask = 0xffffffff;
 584 static int psc_i2s_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
 585                            struct snd_pcm *pcm)
 586 {
 587         struct snd_soc_pcm_runtime *rtd = pcm->private_data;
 588         size_t size = psc_i2s_pcm_hardware.buffer_bytes_max;
 589         int rc = 0;
 590
 591         dev_dbg(rtd->socdev->dev, "psc_i2s_pcm_new(card=%p, dai=%p, pcm=%p)\n",
 592                 card, dai, pcm);
 593
 594         if (!card->dev->dma_mask)
 595                 card->dev->dma_mask = &psc_i2s_pcm_dmamask;
 596         if (!card->dev->coherent_dma_mask)
 597                 card->dev->coherent_dma_mask = 0xffffffff;
 598
 599         if (pcm->streams[0].substream) {
 600                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->dev, size,
 601                                         &pcm->streams[0].substream->dma_buffer);
 602                 if (rc)
 603                         goto playback_alloc_err;
 604         }
 605
 606         if (pcm->streams[1].substream) {
 607                 rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->dev, size,
 608                                         &pcm->streams[1].substream->dma_buffer);
 609                 if (rc)
 610                         goto capture_alloc_err;
 611         }
 612
 613         return 0;
 614
 615  capture_alloc_err:
 616         if (pcm->streams[0].substream)
 617                 snd_dma_free_pages(&pcm->streams[0].substream->dma_buffer);
 618  playback_alloc_err:
 619         dev_err(card->dev, "Cannot allocate buffer(s)\n");
 620         return -ENOMEM;
 621 }
 622
 623 static void psc_i2s_pcm_free(struct snd_pcm *pcm)
 624 {
 625         struct snd_soc_pcm_runtime *rtd = pcm->private_data;
 626         struct snd_pcm_substream *substream;
 627         int stream;
 628
 629         dev_dbg(rtd->socdev->dev, "psc_i2s_pcm_free(pcm=%p)\n", pcm);
 630
 631         for (stream = 0; stream < 2; stream++) {
 632                 substream = pcm->streams[stream].substream;
 633                 if (substream) {
 634                         snd_dma_free_pages(&substream->dma_buffer);
 635                         substream->dma_buffer.area = NULL;
 636                         substream->dma_buffer.addr = 0;
 637                 }
 638         }
 639 }
 640
 641 struct snd_soc_platform psc_i2s_pcm_soc_platform = {
 642         .name           = "mpc5200-psc-audio",
 643         .pcm_ops        = &psc_i2s_pcm_ops,
 644         .pcm_new        = &psc_i2s_pcm_new,
 645         .pcm_free       = &psc_i2s_pcm_free,
 646 };
 647
 648 /* ---------------------------------------------------------------------
 649  * Sysfs attributes for debugging
 650  */
 651
 652 static ssize_t psc_i2s_status_show(struct device *dev,
 653                            struct device_attribute *attr, char *buf)
 654 {
 655         struct psc_i2s *psc_i2s = dev_get_drvdata(dev);
 656
 657         return sprintf(buf, "status=%.4x sicr=%.8x rfnum=%i rfstat=0x%.4x "
 658                         "tfnum=%i tfstat=0x%.4x\n",
 659                         in_be16(&psc_i2s->psc_regs->sr_csr.status),
 660                         in_be32(&psc_i2s->psc_regs->sicr),
 661                         in_be16(&psc_i2s->fifo_regs->rfnum) & 0x1ff,
 662                         in_be16(&psc_i2s->fifo_regs->rfstat),
 663                         in_be16(&psc_i2s->fifo_regs->tfnum) & 0x1ff,
 664                         in_be16(&psc_i2s->fifo_regs->tfstat));
 665 }
 666
 667 static int *psc_i2s_get_stat_attr(struct psc_i2s *psc_i2s, const char *name)
 668 {
 669         if (strcmp(name, "playback_underrun") == 0)
 670                 return &psc_i2s->stats.underrun_count;
 671         if (strcmp(name, "capture_overrun") == 0)
 672                 return &psc_i2s->stats.overrun_count;
 673
 674         return NULL;
 675 }
 676
 677 static ssize_t psc_i2s_stat_show(struct device *dev,
 678                                  struct device_attribute *attr, char *buf)
 679 {
 680         struct psc_i2s *psc_i2s = dev_get_drvdata(dev);
 681         int *attrib;
 682
 683         attrib = psc_i2s_get_stat_attr(psc_i2s, attr->attr.name);
 684         if (!attrib)
 685                 return 0;
 686
 687         return sprintf(buf, "%i\n", *attrib);
 688 }
 689
 690 static ssize_t psc_i2s_stat_store(struct device *dev,
 691                                   struct device_attribute *attr,
 692                                   const char *buf,
 693                                   size_t count)
 694 {
 695         struct psc_i2s *psc_i2s = dev_get_drvdata(dev);
 696         int *attrib;
 697
 698         attrib = psc_i2s_get_stat_attr(psc_i2s, attr->attr.name);
 699         if (!attrib)
 700                 return 0;
 701
 702         *attrib = simple_strtoul(buf, NULL, 0);
 703         return count;
 704 }
 705
 706 static DEVICE_ATTR(status, 0644, psc_i2s_status_show, NULL);
 707 static DEVICE_ATTR(playback_underrun, 0644, psc_i2s_stat_show,
 708                         psc_i2s_stat_store);
 709 static DEVICE_ATTR(capture_overrun, 0644, psc_i2s_stat_show,
 710                         psc_i2s_stat_store);
 711
 712 /* ---------------------------------------------------------------------
 713  * OF platform bus binding code:
 714  * - Probe/remove operations
 715  * - OF device match table
 716  */
 717 static int __devinit psc_i2s_of_probe(struct of_device *op,
 718                                       const struct of_device_id *match)
 719 {
 720         phys_addr_t fifo;
 721         struct psc_i2s *psc_i2s;
 722         struct resource res;
 723         int size, psc_id, irq, rc;
 724         const __be32 *prop;
 725         void __iomem *regs;
 726
 727         dev_dbg(&op->dev, "probing psc i2s device\n");
 728
 729         /* Get the PSC ID */
 730         prop = of_get_property(op->node, "cell-index", &size);
 731         if (!prop || size < sizeof *prop)
 732                 return -ENODEV;
 733         psc_id = be32_to_cpu(*prop);
 734
 735         /* Fetch the registers and IRQ of the PSC */
 736         irq = irq_of_parse_and_map(op->node, 0);
 737         if (of_address_to_resource(op->node, 0, &res)) {
 738                 dev_err(&op->dev, "Missing reg property\n");
 739                 return -ENODEV;
 740         }
 741         regs = ioremap(res.start, 1 + res.end - res.start);
 742         if (!regs) {
 743                 dev_err(&op->dev, "Could not map registers\n");
 744                 return -ENODEV;
 745         }
 746
 747         /* Allocate and initialize the driver private data */
 748         psc_i2s = kzalloc(sizeof *psc_i2s, GFP_KERNEL);
 749         if (!psc_i2s) {
 750                 iounmap(regs);
 751                 return -ENOMEM;
 752         }
 753         spin_lock_init(&psc_i2s->lock);
 754         psc_i2s->irq = irq;
 755         psc_i2s->psc_regs = regs;
 756         psc_i2s->fifo_regs = regs + sizeof *psc_i2s->psc_regs;
 757         psc_i2s->dev = &op->dev;
 758         psc_i2s->playback.psc_i2s = psc_i2s;
 759         psc_i2s->capture.psc_i2s = psc_i2s;
 760         snprintf(psc_i2s->name, sizeof psc_i2s->name, "PSC%u", psc_id+1);
 761
 762         /* Fill out the CPU DAI structure */
 763         memcpy(&psc_i2s->dai, &psc_i2s_dai_template, sizeof psc_i2s->dai);
 764         psc_i2s->dai.private_data = psc_i2s;
 765         psc_i2s->dai.name = psc_i2s->name;
 766         psc_i2s->dai.id = psc_id;
 767
 768         /* Find the address of the fifo data registers and setup the
 769          * DMA tasks */
 770         fifo = res.start + offsetof(struct mpc52xx_psc, buffer.buffer_32);
 771         psc_i2s->capture.bcom_task =
 772                 bcom_psc_gen_bd_rx_init(psc_id, 10, fifo, 512);
 773         psc_i2s->playback.bcom_task =
 774                 bcom_psc_gen_bd_tx_init(psc_id, 10, fifo);
 775         if (!psc_i2s->capture.bcom_task ||
 776             !psc_i2s->playback.bcom_task) {
 777                 dev_err(&op->dev, "Could not allocate bestcomm tasks\n");
 778                 iounmap(regs);
 779                 kfree(psc_i2s);
 780                 return -ENODEV;
 781         }
 782
 783         /* Disable all interrupts and reset the PSC */
 784         out_be16(&psc_i2s->psc_regs->isr_imr.imr, 0);
 785         out_8(&psc_i2s->psc_regs->command, 3 << 4); /* reset transmitter */
 786         out_8(&psc_i2s->psc_regs->command, 2 << 4); /* reset receiver */
 787         out_8(&psc_i2s->psc_regs->command, 1 << 4); /* reset mode */
 788         out_8(&psc_i2s->psc_regs->command, 4 << 4); /* reset error */
 789
 790         /* Configure the serial interface mode; defaulting to CODEC8 mode */
 791         psc_i2s->sicr = MPC52xx_PSC_SICR_DTS1 | MPC52xx_PSC_SICR_I2S |
 792                         MPC52xx_PSC_SICR_CLKPOL;
 793         if (of_get_property(op->node, "fsl,cellslave", NULL))
 794                 psc_i2s->sicr |= MPC52xx_PSC_SICR_CELLSLAVE |
 795                                  MPC52xx_PSC_SICR_GENCLK;
 796         out_be32(&psc_i2s->psc_regs->sicr,
 797                  psc_i2s->sicr | MPC52xx_PSC_SICR_SIM_CODEC_8);
 798
 799         /* Check for the codec handle.  If it is not present then we
 800          * are done */
 801         if (!of_get_property(op->node, "codec-handle", NULL))
 802                 return 0;
 803
 804         /* Set up mode register;
 805          * First write: RxRdy (FIFO Alarm) generates rx FIFO irq
 806          * Second write: register Normal mode for non loopback
 807          */
 808         out_8(&psc_i2s->psc_regs->mode, 0);
 809         out_8(&psc_i2s->psc_regs->mode, 0);
 810
 811         /* Set the TX and RX fifo alarm thresholds */
 812         out_be16(&psc_i2s->fifo_regs->rfalarm, 0x100);
 813         out_8(&psc_i2s->fifo_regs->rfcntl, 0x4);
 814         out_be16(&psc_i2s->fifo_regs->tfalarm, 0x100);
 815         out_8(&psc_i2s->fifo_regs->tfcntl, 0x7);
 816
 817         /* Lookup the IRQ numbers */
 818         psc_i2s->playback.irq =
 819                 bcom_get_task_irq(psc_i2s->playback.bcom_task);
 820         psc_i2s->capture.irq =
 821                 bcom_get_task_irq(psc_i2s->capture.bcom_task);
 822
 823         /* Save what we've done so it can be found again later */
 824         dev_set_drvdata(&op->dev, psc_i2s);
 825
 826         /* Register the SYSFS files */
 827         rc = device_create_file(psc_i2s->dev, &dev_attr_status);
 828         rc |= device_create_file(psc_i2s->dev, &dev_attr_capture_overrun);
 829         rc |= device_create_file(psc_i2s->dev, &dev_attr_playback_underrun);
 830         if (rc)
 831                 dev_info(psc_i2s->dev, "error creating sysfs files\n");
 832
 833         snd_soc_register_platform(&psc_i2s_pcm_soc_platform);
 834
 835         /* Tell the ASoC OF helpers about it */
 836         of_snd_soc_register_platform(&psc_i2s_pcm_soc_platform, op->node,
 837                                      &psc_i2s->dai);
 838
 839         return 0;
 840 }
 841
 842 static int __devexit psc_i2s_of_remove(struct of_device *op)
 843 {
 844         struct psc_i2s *psc_i2s = dev_get_drvdata(&op->dev);
 845
 846         dev_dbg(&op->dev, "psc_i2s_remove()\n");
 847
 848         snd_soc_unregister_platform(&psc_i2s_pcm_soc_platform);
 849
 850         bcom_gen_bd_rx_release(psc_i2s->capture.bcom_task);
 851         bcom_gen_bd_tx_release(psc_i2s->playback.bcom_task);
 852
 853         iounmap(psc_i2s->psc_regs);
 854         iounmap(psc_i2s->fifo_regs);
 855         kfree(psc_i2s);
 856         dev_set_drvdata(&op->dev, NULL);
 857
 858         return 0;
 859 }
 860
 861 /* Match table for of_platform binding */
 862 static struct of_device_id psc_i2s_match[] __devinitdata = {
 863         { .compatible = "fsl,mpc5200-psc-i2s", },
 864         {}
 865 };
 866 MODULE_DEVICE_TABLE(of, psc_i2s_match);
 867
 868 static struct of_platform_driver psc_i2s_driver = {
 869         .match_table = psc_i2s_match,
 870         .probe = psc_i2s_of_probe,
 871         .remove = __devexit_p(psc_i2s_of_remove),
 872         .driver = {
 873                 .name = "mpc5200-psc-i2s",
 874                 .owner = THIS_MODULE,
 875         },
 876 };
 877
 878 /* ---------------------------------------------------------------------
 879  * Module setup and teardown; simply register the of_platform driver
 880  * for the PSC in I2S mode.
 881  */
 882 static int __init psc_i2s_init(void)
 883 {
 884         return of_register_platform_driver(&psc_i2s_driver);
 885 }
 886 module_init(psc_i2s_init);
 887
 888 static void __exit psc_i2s_exit(void)
 889 {
 890         of_unregister_platform_driver(&psc_i2s_driver);
 891 }
 892 module_exit(psc_i2s_exit);
 893
 894