]> pilppa.com Git - linux-2.6-omap-h63xx.git/commitdiff
ALSA: ASoC: Add mpc5200-psc I2S driver
authorGrant Likely <grant.likely@secretlab.ca>
Tue, 29 Jul 2008 10:42:30 +0000 (11:42 +0100)
committerJaroslav Kysela <perex@perex.cz>
Tue, 29 Jul 2008 19:32:23 +0000 (21:32 +0200)
This is an I2S bus driver for the MPC5200 PSC device.  It depends on the
soc-of helper functions to match a PSC device with a codec based on data
in the device tree.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
sound/soc/fsl/Kconfig
sound/soc/fsl/Makefile
sound/soc/fsl/mpc5200_psc_i2s.c [new file with mode: 0644]

index 398f002086785ac6645a330eb6445b2466afbf2f..bba9546ba5f5c30d076cb7962359d9405f1cc0fa 100644 (file)
@@ -17,3 +17,10 @@ config SND_SOC_MPC8610_HPCD
        default y if MPC8610_HPCD
        help
          Say Y if you want to enable audio on the Freescale MPC8610 HPCD.
+
+config SND_SOC_MPC5200_I2S
+       tristate "Freescale MPC5200 PSC in I2S mode driver"
+       select SND_SOC_OF_SIMPLE
+       depends on SND_SOC && PPC_MPC52xx
+       help
+         Say Y here to support the MPC5200 PSCs in I2S mode.
index aa2100b41146d2ae82757e3356f48e217edb0baa..035da4afec34bb8961dfbd86a5ffd23164bb0ce2 100644 (file)
@@ -7,3 +7,5 @@ obj-$(CONFIG_SND_SOC_MPC8610_HPCD) += mpc8610_hpcd.o
 # MPC8610 Platform Support
 obj-$(CONFIG_SND_SOC_MPC8610) += fsl_ssi.o fsl_dma.o
 
+obj-$(CONFIG_SND_SOC_MPC5200_I2S) += mpc5200_psc_i2s.o
+
diff --git a/sound/soc/fsl/mpc5200_psc_i2s.c b/sound/soc/fsl/mpc5200_psc_i2s.c
new file mode 100644 (file)
index 0000000..8692329
--- /dev/null
@@ -0,0 +1,884 @@
+/*
+ * Freescale MPC5200 PSC in I2S mode
+ * ALSA SoC Digital Audio Interface (DAI) driver
+ *
+ * Copyright (C) 2008 Secret Lab Technologies Ltd.
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/dma-mapping.h>
+
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+#include <sound/soc-of-simple.h>
+
+#include <sysdev/bestcomm/bestcomm.h>
+#include <sysdev/bestcomm/gen_bd.h>
+#include <asm/mpc52xx_psc.h>
+
+MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
+MODULE_DESCRIPTION("Freescale MPC5200 PSC in I2S mode ASoC Driver");
+MODULE_LICENSE("GPL");
+
+/**
+ * PSC_I2S_RATES: sample rates supported by the I2S
+ *
+ * This driver currently only supports the PSC running in I2S slave mode,
+ * which means the codec determines the sample rate.  Therefore, we tell
+ * ALSA that we support all rates and let the codec driver decide what rates
+ * are really supported.
+ */
+#define PSC_I2S_RATES (SNDRV_PCM_RATE_5512 | SNDRV_PCM_RATE_8000_192000 | \
+                       SNDRV_PCM_RATE_CONTINUOUS)
+
+/**
+ * PSC_I2S_FORMATS: audio formats supported by the PSC I2S mode
+ */
+#define PSC_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | \
+                        SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S24_BE | \
+                        SNDRV_PCM_FMTBIT_S32_BE)
+
+/**
+ * psc_i2s_stream - Data specific to a single stream (playback or capture)
+ * @active:            flag indicating if the stream is active
+ * @psc_i2s:           pointer back to parent psc_i2s data structure
+ * @bcom_task:         bestcomm task structure
+ * @irq:               irq number for bestcomm task
+ * @period_start:      physical address of start of DMA region
+ * @period_end:                physical address of end of DMA region
+ * @period_next_pt:    physical address of next DMA buffer to enqueue
+ * @period_bytes:      size of DMA period in bytes
+ */
+struct psc_i2s_stream {
+       int active;
+       struct psc_i2s *psc_i2s;
+       struct bcom_task *bcom_task;
+       int irq;
+       struct snd_pcm_substream *stream;
+       dma_addr_t period_start;
+       dma_addr_t period_end;
+       dma_addr_t period_next_pt;
+       dma_addr_t period_current_pt;
+       int period_bytes;
+};
+
+/**
+ * psc_i2s - Private driver data
+ * @name: short name for this device ("PSC0", "PSC1", etc)
+ * @psc_regs: pointer to the PSC's registers
+ * @fifo_regs: pointer to the PSC's FIFO registers
+ * @irq: IRQ of this PSC
+ * @dev: struct device pointer
+ * @dai: the CPU DAI for this device
+ * @sicr: Base value used in serial interface control register; mode is ORed
+ *        with this value.
+ * @playback: Playback stream context data
+ * @capture: Capture stream context data
+ */
+struct psc_i2s {
+       char name[32];
+       struct mpc52xx_psc __iomem *psc_regs;
+       struct mpc52xx_psc_fifo __iomem *fifo_regs;
+       unsigned int irq;
+       struct device *dev;
+       struct snd_soc_dai dai;
+       spinlock_t lock;
+       u32 sicr;
+
+       /* per-stream data */
+       struct psc_i2s_stream playback;
+       struct psc_i2s_stream capture;
+
+       /* Statistics */
+       struct {
+               int overrun_count;
+               int underrun_count;
+       } stats;
+};
+
+/*
+ * Interrupt handlers
+ */
+static irqreturn_t psc_i2s_status_irq(int irq, void *_psc_i2s)
+{
+       struct psc_i2s *psc_i2s = _psc_i2s;
+       struct mpc52xx_psc __iomem *regs = psc_i2s->psc_regs;
+       u16 isr;
+
+       isr = in_be16(&regs->mpc52xx_psc_isr);
+
+       /* Playback underrun error */
+       if (psc_i2s->playback.active && (isr & MPC52xx_PSC_IMR_TXEMP))
+               psc_i2s->stats.underrun_count++;
+
+       /* Capture overrun error */
+       if (psc_i2s->capture.active && (isr & MPC52xx_PSC_IMR_ORERR))
+               psc_i2s->stats.overrun_count++;
+
+       out_8(&regs->command, 4 << 4);  /* reset the error status */
+
+       return IRQ_HANDLED;
+}
+
+/**
+ * psc_i2s_bcom_enqueue_next_buffer - Enqueue another audio buffer
+ * @s: pointer to stream private data structure
+ *
+ * Enqueues another audio period buffer into the bestcomm queue.
+ *
+ * Note: The routine must only be called when there is space available in
+ * the queue.  Otherwise the enqueue will fail and the audio ring buffer
+ * will get out of sync
+ */
+static void psc_i2s_bcom_enqueue_next_buffer(struct psc_i2s_stream *s)
+{
+       struct bcom_bd *bd;
+
+       /* Prepare and enqueue the next buffer descriptor */
+       bd = bcom_prepare_next_buffer(s->bcom_task);
+       bd->status = s->period_bytes;
+       bd->data[0] = s->period_next_pt;
+       bcom_submit_next_buffer(s->bcom_task, NULL);
+
+       /* Update for next period */
+       s->period_next_pt += s->period_bytes;
+       if (s->period_next_pt >= s->period_end)
+               s->period_next_pt = s->period_start;
+}
+
+/* Bestcomm DMA irq handler */
+static irqreturn_t psc_i2s_bcom_irq(int irq, void *_psc_i2s_stream)
+{
+       struct psc_i2s_stream *s = _psc_i2s_stream;
+
+       /* For each finished period, dequeue the completed period buffer
+        * and enqueue a new one in it's place. */
+       while (bcom_buffer_done(s->bcom_task)) {
+               bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
+               s->period_current_pt += s->period_bytes;
+               if (s->period_current_pt >= s->period_end)
+                       s->period_current_pt = s->period_start;
+               psc_i2s_bcom_enqueue_next_buffer(s);
+               bcom_enable(s->bcom_task);
+       }
+
+       /* If the stream is active, then also inform the PCM middle layer
+        * of the period finished event. */
+       if (s->active)
+               snd_pcm_period_elapsed(s->stream);
+
+       return IRQ_HANDLED;
+}
+
+/**
+ * psc_i2s_startup: create a new substream
+ *
+ * This is the first function called when a stream is opened.
+ *
+ * If this is the first stream open, then grab the IRQ and program most of
+ * the PSC registers.
+ */
+static int psc_i2s_startup(struct snd_pcm_substream *substream)
+{
+       struct snd_soc_pcm_runtime *rtd = substream->private_data;
+       struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+       int rc;
+
+       dev_dbg(psc_i2s->dev, "psc_i2s_startup(substream=%p)\n", substream);
+
+       if (!psc_i2s->playback.active &&
+           !psc_i2s->capture.active) {
+               /* Setup the IRQs */
+               rc = request_irq(psc_i2s->irq, &psc_i2s_status_irq, IRQF_SHARED,
+                                "psc-i2s-status", psc_i2s);
+               rc |= request_irq(psc_i2s->capture.irq,
+                                 &psc_i2s_bcom_irq, IRQF_SHARED,
+                                 "psc-i2s-capture", &psc_i2s->capture);
+               rc |= request_irq(psc_i2s->playback.irq,
+                                 &psc_i2s_bcom_irq, IRQF_SHARED,
+                                 "psc-i2s-playback", &psc_i2s->playback);
+               if (rc) {
+                       free_irq(psc_i2s->irq, psc_i2s);
+                       free_irq(psc_i2s->capture.irq,
+                                &psc_i2s->capture);
+                       free_irq(psc_i2s->playback.irq,
+                                &psc_i2s->playback);
+                       return -ENODEV;
+               }
+       }
+
+       return 0;
+}
+
+static int psc_i2s_hw_params(struct snd_pcm_substream *substream,
+                                struct snd_pcm_hw_params *params)
+{
+       struct snd_soc_pcm_runtime *rtd = substream->private_data;
+       struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+       u32 mode;
+
+       dev_dbg(psc_i2s->dev, "%s(substream=%p) p_size=%i p_bytes=%i"
+               " periods=%i buffer_size=%i  buffer_bytes=%i\n",
+               __func__, substream, params_period_size(params),
+               params_period_bytes(params), params_periods(params),
+               params_buffer_size(params), params_buffer_bytes(params));
+
+       switch (params_format(params)) {
+       case SNDRV_PCM_FORMAT_S8:
+               mode = MPC52xx_PSC_SICR_SIM_CODEC_8;
+               break;
+       case SNDRV_PCM_FORMAT_S16_BE:
+               mode = MPC52xx_PSC_SICR_SIM_CODEC_16;
+               break;
+       case SNDRV_PCM_FORMAT_S24_BE:
+               mode = MPC52xx_PSC_SICR_SIM_CODEC_24;
+               break;
+       case SNDRV_PCM_FORMAT_S32_BE:
+               mode = MPC52xx_PSC_SICR_SIM_CODEC_32;
+               break;
+       default:
+               dev_dbg(psc_i2s->dev, "invalid format\n");
+               return -EINVAL;
+       }
+       out_be32(&psc_i2s->psc_regs->sicr, psc_i2s->sicr | mode);
+
+       snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
+
+       return 0;
+}
+
+static int psc_i2s_hw_free(struct snd_pcm_substream *substream)
+{
+       snd_pcm_set_runtime_buffer(substream, NULL);
+       return 0;
+}
+
+/**
+ * psc_i2s_trigger: start and stop the DMA transfer.
+ *
+ * This function is called by ALSA to start, stop, pause, and resume the DMA
+ * transfer of data.
+ */
+static int psc_i2s_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+       struct snd_soc_pcm_runtime *rtd = substream->private_data;
+       struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+       struct snd_pcm_runtime *runtime = substream->runtime;
+       struct psc_i2s_stream *s;
+       struct mpc52xx_psc __iomem *regs = psc_i2s->psc_regs;
+       u16 imr;
+       u8 psc_cmd;
+       long flags;
+
+       if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
+               s = &psc_i2s->capture;
+       else
+               s = &psc_i2s->playback;
+
+       dev_dbg(psc_i2s->dev, "psc_i2s_trigger(substream=%p, cmd=%i)"
+               " stream_id=%i\n",
+               substream, cmd, substream->pstr->stream);
+
+       switch (cmd) {
+       case SNDRV_PCM_TRIGGER_START:
+               s->period_bytes = frames_to_bytes(runtime,
+                                                 runtime->period_size);
+               s->period_start = virt_to_phys(runtime->dma_area);
+               s->period_end = s->period_start +
+                               (s->period_bytes * runtime->periods);
+               s->period_next_pt = s->period_start;
+               s->period_current_pt = s->period_start;
+               s->active = 1;
+
+               /* First; reset everything */
+               if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) {
+                       out_8(&regs->command, MPC52xx_PSC_RST_RX);
+                       out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
+               } else {
+                       out_8(&regs->command, MPC52xx_PSC_RST_TX);
+                       out_8(&regs->command, MPC52xx_PSC_RST_ERR_STAT);
+               }
+
+               /* Next, fill up the bestcomm bd queue and enable DMA.
+                * This will begin filling the PSC's fifo. */
+               if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
+                       bcom_gen_bd_rx_reset(s->bcom_task);
+               else
+                       bcom_gen_bd_tx_reset(s->bcom_task);
+               while (!bcom_queue_full(s->bcom_task))
+                       psc_i2s_bcom_enqueue_next_buffer(s);
+               bcom_enable(s->bcom_task);
+
+               /* Due to errata in the i2s mode; need to line up enabling
+                * the transmitter with a transition on the frame sync
+                * line */
+
+               spin_lock_irqsave(&psc_i2s->lock, flags);
+               /* first make sure it is low */
+               while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) != 0)
+                       ;
+               /* then wait for the transition to high */
+               while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) == 0)
+                       ;
+               /* Finally, enable the PSC.
+                * Receiver must always be enabled; even when we only want
+                * transmit.  (see 15.3.2.3 of MPC5200B User's Guide) */
+               psc_cmd = MPC52xx_PSC_RX_ENABLE;
+               if (substream->pstr->stream == SNDRV_PCM_STREAM_PLAYBACK)
+                       psc_cmd |= MPC52xx_PSC_TX_ENABLE;
+               out_8(&regs->command, psc_cmd);
+               spin_unlock_irqrestore(&psc_i2s->lock, flags);
+
+               break;
+
+       case SNDRV_PCM_TRIGGER_STOP:
+               /* Turn off the PSC */
+               s->active = 0;
+               if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE) {
+                       if (!psc_i2s->playback.active) {
+                               out_8(&regs->command, 2 << 4);  /* reset rx */
+                               out_8(&regs->command, 3 << 4);  /* reset tx */
+                               out_8(&regs->command, 4 << 4);  /* reset err */
+                       }
+               } else {
+                       out_8(&regs->command, 3 << 4);  /* reset tx */
+                       out_8(&regs->command, 4 << 4);  /* reset err */
+                       if (!psc_i2s->capture.active)
+                               out_8(&regs->command, 2 << 4);  /* reset rx */
+               }
+
+               bcom_disable(s->bcom_task);
+               while (!bcom_queue_empty(s->bcom_task))
+                       bcom_retrieve_buffer(s->bcom_task, NULL, NULL);
+
+               break;
+
+       default:
+               dev_dbg(psc_i2s->dev, "invalid command\n");
+               return -EINVAL;
+       }
+
+       /* Update interrupt enable settings */
+       imr = 0;
+       if (psc_i2s->playback.active)
+               imr |= MPC52xx_PSC_IMR_TXEMP;
+       if (psc_i2s->capture.active)
+               imr |= MPC52xx_PSC_IMR_ORERR;
+       out_be16(&regs->isr_imr.imr, imr);
+
+       return 0;
+}
+
+/**
+ * psc_i2s_shutdown: shutdown the data transfer on a stream
+ *
+ * Shutdown the PSC if there are no other substreams open.
+ */
+static void psc_i2s_shutdown(struct snd_pcm_substream *substream)
+{
+       struct snd_soc_pcm_runtime *rtd = substream->private_data;
+       struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+
+       dev_dbg(psc_i2s->dev, "psc_i2s_shutdown(substream=%p)\n", substream);
+
+       /*
+        * If this is the last active substream, disable the PSC and release
+        * the IRQ.
+        */
+       if (!psc_i2s->playback.active &&
+           !psc_i2s->capture.active) {
+
+               /* Disable all interrupts and reset the PSC */
+               out_be16(&psc_i2s->psc_regs->isr_imr.imr, 0);
+               out_8(&psc_i2s->psc_regs->command, 3 << 4); /* reset tx */
+               out_8(&psc_i2s->psc_regs->command, 2 << 4); /* reset rx */
+               out_8(&psc_i2s->psc_regs->command, 1 << 4); /* reset mode */
+               out_8(&psc_i2s->psc_regs->command, 4 << 4); /* reset error */
+
+               /* Release irqs */
+               free_irq(psc_i2s->irq, psc_i2s);
+               free_irq(psc_i2s->capture.irq, &psc_i2s->capture);
+               free_irq(psc_i2s->playback.irq, &psc_i2s->playback);
+       }
+}
+
+/**
+ * psc_i2s_set_sysclk: set the clock frequency and direction
+ *
+ * This function is called by the machine driver to tell us what the clock
+ * frequency and direction are.
+ *
+ * Currently, we only support operating as a clock slave (SND_SOC_CLOCK_IN),
+ * and we don't care about the frequency.  Return an error if the direction
+ * is not SND_SOC_CLOCK_IN.
+ *
+ * @clk_id: reserved, should be zero
+ * @freq: the frequency of the given clock ID, currently ignored
+ * @dir: SND_SOC_CLOCK_IN (clock slave) or SND_SOC_CLOCK_OUT (clock master)
+ */
+static int psc_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
+                             int clk_id, unsigned int freq, int dir)
+{
+       struct psc_i2s *psc_i2s = cpu_dai->private_data;
+       dev_dbg(psc_i2s->dev, "psc_i2s_set_sysclk(cpu_dai=%p, dir=%i)\n",
+                               cpu_dai, dir);
+       return (dir == SND_SOC_CLOCK_IN) ? 0 : -EINVAL;
+}
+
+/**
+ * psc_i2s_set_fmt: set the serial format.
+ *
+ * This function is called by the machine driver to tell us what serial
+ * format to use.
+ *
+ * This driver only supports I2S mode.  Return an error if the format is
+ * not SND_SOC_DAIFMT_I2S.
+ *
+ * @format: one of SND_SOC_DAIFMT_xxx
+ */
+static int psc_i2s_set_fmt(struct snd_soc_dai *cpu_dai, unsigned int format)
+{
+       struct psc_i2s *psc_i2s = cpu_dai->private_data;
+       dev_dbg(psc_i2s->dev, "psc_i2s_set_fmt(cpu_dai=%p, format=%i)\n",
+                               cpu_dai, format);
+       return (format == SND_SOC_DAIFMT_I2S) ? 0 : -EINVAL;
+}
+
+/* ---------------------------------------------------------------------
+ * ALSA SoC Bindings
+ *
+ * - Digital Audio Interface (DAI) template
+ * - create/destroy dai hooks
+ */
+
+/**
+ * psc_i2s_dai_template: template CPU Digital Audio Interface
+ */
+static struct snd_soc_dai psc_i2s_dai_template = {
+       .type = SND_SOC_DAI_I2S,
+       .playback = {
+               .channels_min = 2,
+               .channels_max = 2,
+               .rates = PSC_I2S_RATES,
+               .formats = PSC_I2S_FORMATS,
+       },
+       .capture = {
+               .channels_min = 2,
+               .channels_max = 2,
+               .rates = PSC_I2S_RATES,
+               .formats = PSC_I2S_FORMATS,
+       },
+       .ops = {
+               .startup = psc_i2s_startup,
+               .hw_params = psc_i2s_hw_params,
+               .hw_free = psc_i2s_hw_free,
+               .shutdown = psc_i2s_shutdown,
+               .trigger = psc_i2s_trigger,
+       },
+       .dai_ops = {
+               .set_sysclk = psc_i2s_set_sysclk,
+               .set_fmt = psc_i2s_set_fmt,
+       },
+};
+
+/* ---------------------------------------------------------------------
+ * The PSC I2S 'ASoC platform' driver
+ *
+ * Can be referenced by an 'ASoC machine' driver
+ * This driver only deals with the audio bus; it doesn't have any
+ * interaction with the attached codec
+ */
+
+static const struct snd_pcm_hardware psc_i2s_pcm_hardware = {
+       .info = SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_MMAP_VALID |
+               SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER,
+       .formats = SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE |
+                  SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE,
+       .rate_min = 8000,
+       .rate_max = 48000,
+       .channels_min = 2,
+       .channels_max = 2,
+       .period_bytes_max       = 1024 * 1024,
+       .period_bytes_min       = 32,
+       .periods_min            = 2,
+       .periods_max            = 256,
+       .buffer_bytes_max       = 2 * 1024 * 1024,
+       .fifo_size              = 0,
+};
+
+static int psc_i2s_pcm_open(struct snd_pcm_substream *substream)
+{
+       struct snd_soc_pcm_runtime *rtd = substream->private_data;
+       struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+       struct psc_i2s_stream *s;
+
+       dev_dbg(psc_i2s->dev, "psc_i2s_pcm_open(substream=%p)\n", substream);
+
+       if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
+               s = &psc_i2s->capture;
+       else
+               s = &psc_i2s->playback;
+
+       snd_soc_set_runtime_hwparams(substream, &psc_i2s_pcm_hardware);
+
+       s->stream = substream;
+       return 0;
+}
+
+static int psc_i2s_pcm_close(struct snd_pcm_substream *substream)
+{
+       struct snd_soc_pcm_runtime *rtd = substream->private_data;
+       struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+       struct psc_i2s_stream *s;
+
+       dev_dbg(psc_i2s->dev, "psc_i2s_pcm_close(substream=%p)\n", substream);
+
+       if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
+               s = &psc_i2s->capture;
+       else
+               s = &psc_i2s->playback;
+
+       s->stream = NULL;
+       return 0;
+}
+
+static snd_pcm_uframes_t
+psc_i2s_pcm_pointer(struct snd_pcm_substream *substream)
+{
+       struct snd_soc_pcm_runtime *rtd = substream->private_data;
+       struct psc_i2s *psc_i2s = rtd->dai->cpu_dai->private_data;
+       struct psc_i2s_stream *s;
+       dma_addr_t count;
+
+       if (substream->pstr->stream == SNDRV_PCM_STREAM_CAPTURE)
+               s = &psc_i2s->capture;
+       else
+               s = &psc_i2s->playback;
+
+       count = s->period_current_pt - s->period_start;
+
+       return bytes_to_frames(substream->runtime, count);
+}
+
+static struct snd_pcm_ops psc_i2s_pcm_ops = {
+       .open           = psc_i2s_pcm_open,
+       .close          = psc_i2s_pcm_close,
+       .ioctl          = snd_pcm_lib_ioctl,
+       .pointer        = psc_i2s_pcm_pointer,
+};
+
+static u64 psc_i2s_pcm_dmamask = 0xffffffff;
+static int psc_i2s_pcm_new(struct snd_card *card, struct snd_soc_dai *dai,
+                          struct snd_pcm *pcm)
+{
+       struct snd_soc_pcm_runtime *rtd = pcm->private_data;
+       size_t size = psc_i2s_pcm_hardware.buffer_bytes_max;
+       int rc = 0;
+
+       dev_dbg(rtd->socdev->dev, "psc_i2s_pcm_new(card=%p, dai=%p, pcm=%p)\n",
+               card, dai, pcm);
+
+       if (!card->dev->dma_mask)
+               card->dev->dma_mask = &psc_i2s_pcm_dmamask;
+       if (!card->dev->coherent_dma_mask)
+               card->dev->coherent_dma_mask = 0xffffffff;
+
+       if (pcm->streams[0].substream) {
+               rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->dev, size,
+                                       &pcm->streams[0].substream->dma_buffer);
+               if (rc)
+                       goto playback_alloc_err;
+       }
+
+       if (pcm->streams[1].substream) {
+               rc = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, pcm->dev, size,
+                                       &pcm->streams[1].substream->dma_buffer);
+               if (rc)
+                       goto capture_alloc_err;
+       }
+
+       return 0;
+
+ capture_alloc_err:
+       if (pcm->streams[0].substream)
+               snd_dma_free_pages(&pcm->streams[0].substream->dma_buffer);
+ playback_alloc_err:
+       dev_err(card->dev, "Cannot allocate buffer(s)\n");
+       return -ENOMEM;
+}
+
+static void psc_i2s_pcm_free(struct snd_pcm *pcm)
+{
+       struct snd_soc_pcm_runtime *rtd = pcm->private_data;
+       struct snd_pcm_substream *substream;
+       int stream;
+
+       dev_dbg(rtd->socdev->dev, "psc_i2s_pcm_free(pcm=%p)\n", pcm);
+
+       for (stream = 0; stream < 2; stream++) {
+               substream = pcm->streams[stream].substream;
+               if (substream) {
+                       snd_dma_free_pages(&substream->dma_buffer);
+                       substream->dma_buffer.area = NULL;
+                       substream->dma_buffer.addr = 0;
+               }
+       }
+}
+
+struct snd_soc_platform psc_i2s_pcm_soc_platform = {
+       .name           = "mpc5200-psc-audio",
+       .pcm_ops        = &psc_i2s_pcm_ops,
+       .pcm_new        = &psc_i2s_pcm_new,
+       .pcm_free       = &psc_i2s_pcm_free,
+};
+
+/* ---------------------------------------------------------------------
+ * Sysfs attributes for debugging
+ */
+
+static ssize_t psc_i2s_status_show(struct device *dev,
+                          struct device_attribute *attr, char *buf)
+{
+       struct psc_i2s *psc_i2s = dev_get_drvdata(dev);
+
+       return sprintf(buf, "status=%.4x sicr=%.8x rfnum=%i rfstat=0x%.4x "
+                       "tfnum=%i tfstat=0x%.4x\n",
+                       in_be16(&psc_i2s->psc_regs->sr_csr.status),
+                       in_be32(&psc_i2s->psc_regs->sicr),
+                       in_be16(&psc_i2s->fifo_regs->rfnum) & 0x1ff,
+                       in_be16(&psc_i2s->fifo_regs->rfstat),
+                       in_be16(&psc_i2s->fifo_regs->tfnum) & 0x1ff,
+                       in_be16(&psc_i2s->fifo_regs->tfstat));
+}
+
+static int *psc_i2s_get_stat_attr(struct psc_i2s *psc_i2s, const char *name)
+{
+       if (strcmp(name, "playback_underrun") == 0)
+               return &psc_i2s->stats.underrun_count;
+       if (strcmp(name, "capture_overrun") == 0)
+               return &psc_i2s->stats.overrun_count;
+
+       return NULL;
+}
+
+static ssize_t psc_i2s_stat_show(struct device *dev,
+                                struct device_attribute *attr, char *buf)
+{
+       struct psc_i2s *psc_i2s = dev_get_drvdata(dev);
+       int *attrib;
+
+       attrib = psc_i2s_get_stat_attr(psc_i2s, attr->attr.name);
+       if (!attrib)
+               return 0;
+
+       return sprintf(buf, "%i\n", *attrib);
+}
+
+static ssize_t psc_i2s_stat_store(struct device *dev,
+                                 struct device_attribute *attr,
+                                 const char *buf,
+                                 size_t count)
+{
+       struct psc_i2s *psc_i2s = dev_get_drvdata(dev);
+       int *attrib;
+
+       attrib = psc_i2s_get_stat_attr(psc_i2s, attr->attr.name);
+       if (!attrib)
+               return 0;
+
+       *attrib = simple_strtoul(buf, NULL, 0);
+       return count;
+}
+
+DEVICE_ATTR(status, 0644, psc_i2s_status_show, NULL);
+DEVICE_ATTR(playback_underrun, 0644, psc_i2s_stat_show, psc_i2s_stat_store);
+DEVICE_ATTR(capture_overrun, 0644, psc_i2s_stat_show, psc_i2s_stat_store);
+
+/* ---------------------------------------------------------------------
+ * OF platform bus binding code:
+ * - Probe/remove operations
+ * - OF device match table
+ */
+static int __devinit psc_i2s_of_probe(struct of_device *op,
+                                     const struct of_device_id *match)
+{
+       phys_addr_t fifo;
+       struct psc_i2s *psc_i2s;
+       struct resource res;
+       int size, psc_id, irq, rc;
+       const __be32 *prop;
+       void __iomem *regs;
+
+       dev_dbg(&op->dev, "probing psc i2s device\n");
+
+       /* Get the PSC ID */
+       prop = of_get_property(op->node, "cell-index", &size);
+       if (!prop || size < sizeof *prop)
+               return -ENODEV;
+       psc_id = be32_to_cpu(*prop);
+
+       /* Fetch the registers and IRQ of the PSC */
+       irq = irq_of_parse_and_map(op->node, 0);
+       if (of_address_to_resource(op->node, 0, &res)) {
+               dev_err(&op->dev, "Missing reg property\n");
+               return -ENODEV;
+       }
+       regs = ioremap(res.start, 1 + res.end - res.start);
+       if (!regs) {
+               dev_err(&op->dev, "Could not map registers\n");
+               return -ENODEV;
+       }
+
+       /* Allocate and initialize the driver private data */
+       psc_i2s = kzalloc(sizeof *psc_i2s, GFP_KERNEL);
+       if (!psc_i2s) {
+               iounmap(regs);
+               return -ENOMEM;
+       }
+       spin_lock_init(&psc_i2s->lock);
+       psc_i2s->irq = irq;
+       psc_i2s->psc_regs = regs;
+       psc_i2s->fifo_regs = regs + sizeof *psc_i2s->psc_regs;
+       psc_i2s->dev = &op->dev;
+       psc_i2s->playback.psc_i2s = psc_i2s;
+       psc_i2s->capture.psc_i2s = psc_i2s;
+       snprintf(psc_i2s->name, sizeof psc_i2s->name, "PSC%u", psc_id+1);
+
+       /* Fill out the CPU DAI structure */
+       memcpy(&psc_i2s->dai, &psc_i2s_dai_template, sizeof psc_i2s->dai);
+       psc_i2s->dai.private_data = psc_i2s;
+       psc_i2s->dai.name = psc_i2s->name;
+       psc_i2s->dai.id = psc_id;
+
+       /* Find the address of the fifo data registers and setup the
+        * DMA tasks */
+       fifo = res.start + offsetof(struct mpc52xx_psc, buffer.buffer_32);
+       psc_i2s->capture.bcom_task =
+               bcom_psc_gen_bd_rx_init(psc_id, 10, fifo, 512);
+       psc_i2s->playback.bcom_task =
+               bcom_psc_gen_bd_tx_init(psc_id, 10, fifo);
+       if (!psc_i2s->capture.bcom_task ||
+           !psc_i2s->playback.bcom_task) {
+               dev_err(&op->dev, "Could not allocate bestcomm tasks\n");
+               iounmap(regs);
+               kfree(psc_i2s);
+               return -ENODEV;
+       }
+
+       /* Disable all interrupts and reset the PSC */
+       out_be16(&psc_i2s->psc_regs->isr_imr.imr, 0);
+       out_8(&psc_i2s->psc_regs->command, 3 << 4); /* reset transmitter */
+       out_8(&psc_i2s->psc_regs->command, 2 << 4); /* reset receiver */
+       out_8(&psc_i2s->psc_regs->command, 1 << 4); /* reset mode */
+       out_8(&psc_i2s->psc_regs->command, 4 << 4); /* reset error */
+
+       /* Configure the serial interface mode; defaulting to CODEC8 mode */
+       psc_i2s->sicr = MPC52xx_PSC_SICR_DTS1 | MPC52xx_PSC_SICR_I2S |
+                       MPC52xx_PSC_SICR_CLKPOL;
+       if (of_get_property(op->node, "fsl,cellslave", NULL))
+               psc_i2s->sicr |= MPC52xx_PSC_SICR_CELLSLAVE |
+                                MPC52xx_PSC_SICR_GENCLK;
+       out_be32(&psc_i2s->psc_regs->sicr,
+                psc_i2s->sicr | MPC52xx_PSC_SICR_SIM_CODEC_8);
+
+       /* Check for the codec handle.  If it is not present then we
+        * are done */
+       if (!of_get_property(op->node, "codec-handle", NULL))
+               return 0;
+
+       /* Set up mode register;
+        * First write: RxRdy (FIFO Alarm) generates rx FIFO irq
+        * Second write: register Normal mode for non loopback
+        */
+       out_8(&psc_i2s->psc_regs->mode, 0);
+       out_8(&psc_i2s->psc_regs->mode, 0);
+
+       /* Set the TX and RX fifo alarm thresholds */
+       out_be16(&psc_i2s->fifo_regs->rfalarm, 0x100);
+       out_8(&psc_i2s->fifo_regs->rfcntl, 0x4);
+       out_be16(&psc_i2s->fifo_regs->tfalarm, 0x100);
+       out_8(&psc_i2s->fifo_regs->tfcntl, 0x7);
+
+       /* Lookup the IRQ numbers */
+       psc_i2s->playback.irq =
+               bcom_get_task_irq(psc_i2s->playback.bcom_task);
+       psc_i2s->capture.irq =
+               bcom_get_task_irq(psc_i2s->capture.bcom_task);
+
+       /* Save what we've done so it can be found again later */
+       dev_set_drvdata(&op->dev, psc_i2s);
+
+       /* Register the SYSFS files */
+       rc = device_create_file(psc_i2s->dev, &dev_attr_status);
+       rc = device_create_file(psc_i2s->dev, &dev_attr_capture_overrun);
+       rc = device_create_file(psc_i2s->dev, &dev_attr_playback_underrun);
+       if (rc)
+               dev_info(psc_i2s->dev, "error creating sysfs files\n");
+
+       /* Tell the ASoC OF helpers about it */
+       of_snd_soc_register_platform(&psc_i2s_pcm_soc_platform, op->node,
+                                    &psc_i2s->dai);
+
+       return 0;
+}
+
+static int __devexit psc_i2s_of_remove(struct of_device *op)
+{
+       struct psc_i2s *psc_i2s = dev_get_drvdata(&op->dev);
+
+       dev_dbg(&op->dev, "psc_i2s_remove()\n");
+
+       bcom_gen_bd_rx_release(psc_i2s->capture.bcom_task);
+       bcom_gen_bd_tx_release(psc_i2s->playback.bcom_task);
+
+       iounmap(psc_i2s->psc_regs);
+       iounmap(psc_i2s->fifo_regs);
+       kfree(psc_i2s);
+       dev_set_drvdata(&op->dev, NULL);
+
+       return 0;
+}
+
+/* Match table for of_platform binding */
+static struct of_device_id psc_i2s_match[] __devinitdata = {
+       { .compatible = "fsl,mpc5200-psc-i2s", },
+       {}
+};
+MODULE_DEVICE_TABLE(of, psc_i2s_match);
+
+static struct of_platform_driver psc_i2s_driver = {
+       .match_table = psc_i2s_match,
+       .probe = psc_i2s_of_probe,
+       .remove = __devexit_p(psc_i2s_of_remove),
+       .driver = {
+               .name = "mpc5200-psc-i2s",
+               .owner = THIS_MODULE,
+       },
+};
+
+/* ---------------------------------------------------------------------
+ * Module setup and teardown; simply register the of_platform driver
+ * for the PSC in I2S mode.
+ */
+static int __init psc_i2s_init(void)
+{
+       return of_register_platform_driver(&psc_i2s_driver);
+}
+module_init(psc_i2s_init);
+
+static void __exit psc_i2s_exit(void)
+{
+       of_unregister_platform_driver(&psc_i2s_driver);
+}
+module_exit(psc_i2s_exit);
+
+