Initial import

1 files changed, 1111 insertions, 0 deletions

diff --git a/sound/arm/aaci.c b/sound/arm/aaci.c
new file mode 100644
index 000000000..4140b1b95
--- /dev/null
+++ b/sound/arm/aaci.c
@@ -0,0 +1,1111 @@
+/*
+ *  linux/sound/arm/aaci.c - ARM PrimeCell AACI PL041 driver
+ *
+ *  Copyright (C) 2003 Deep Blue Solutions Ltd, All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ *  Documentation: ARM DDI 0173B
+ */
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/device.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/amba/bus.h>
+#include <linux/io.h>
+
+#include <sound/core.h>
+#include <sound/initval.h>
+#include <sound/ac97_codec.h>
+#include <sound/pcm.h>
+#include <sound/pcm_params.h>
+
+#include "aaci.h"
+
+#define DRIVER_NAME	"aaci-pl041"
+
+#define FRAME_PERIOD_US	21
+
+/*
+ * PM support is not complete.  Turn it off.
+ */
+#undef CONFIG_PM
+
+static void aaci_ac97_select_codec(struct aaci *aaci, struct snd_ac97 *ac97)
+{
+	u32 v, maincr = aaci->maincr | MAINCR_SCRA(ac97->num);
+
+	/*
+	 * Ensure that the slot 1/2 RX registers are empty.
+	 */
+	v = readl(aaci->base + AACI_SLFR);
+	if (v & SLFR_2RXV)
+		readl(aaci->base + AACI_SL2RX);
+	if (v & SLFR_1RXV)
+		readl(aaci->base + AACI_SL1RX);
+
+	if (maincr != readl(aaci->base + AACI_MAINCR)) {
+		writel(maincr, aaci->base + AACI_MAINCR);
+		readl(aaci->base + AACI_MAINCR);
+		udelay(1);
+	}
+}
+
+/*
+ * P29:
+ *  The recommended use of programming the external codec through slot 1
+ *  and slot 2 data is to use the channels during setup routines and the
+ *  slot register at any other time.  The data written into slot 1, slot 2
+ *  and slot 12 registers is transmitted only when their corresponding
+ *  SI1TxEn, SI2TxEn and SI12TxEn bits are set in the AACI_MAINCR
+ *  register.
+ */
+static void aaci_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
+			    unsigned short val)
+{
+	struct aaci *aaci = ac97->private_data;
+	int timeout;
+	u32 v;
+
+	if (ac97->num >= 4)
+		return;
+
+	mutex_lock(&aaci->ac97_sem);
+
+	aaci_ac97_select_codec(aaci, ac97);
+
+	/*
+	 * P54: You must ensure that AACI_SL2TX is always written
+	 * to, if required, before data is written to AACI_SL1TX.
+	 */
+	writel(val << 4, aaci->base + AACI_SL2TX);
+	writel(reg << 12, aaci->base + AACI_SL1TX);
+
+	/* Initially, wait one frame period */
+	udelay(FRAME_PERIOD_US);
+
+	/* And then wait an additional eight frame periods for it to be sent */
+	timeout = FRAME_PERIOD_US * 8;
+	do {
+		udelay(1);
+		v = readl(aaci->base + AACI_SLFR);
+	} while ((v & (SLFR_1TXB|SLFR_2TXB)) && --timeout);
+
+	if (v & (SLFR_1TXB|SLFR_2TXB))
+		dev_err(&aaci->dev->dev,
+			"timeout waiting for write to complete\n");
+
+	mutex_unlock(&aaci->ac97_sem);
+}
+
+/*
+ * Read an AC'97 register.
+ */
+static unsigned short aaci_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
+{
+	struct aaci *aaci = ac97->private_data;
+	int timeout, retries = 10;
+	u32 v;
+
+	if (ac97->num >= 4)
+		return ~0;
+
+	mutex_lock(&aaci->ac97_sem);
+
+	aaci_ac97_select_codec(aaci, ac97);
+
+	/*
+	 * Write the register address to slot 1.
+	 */
+	writel((reg << 12) | (1 << 19), aaci->base + AACI_SL1TX);
+
+	/* Initially, wait one frame period */
+	udelay(FRAME_PERIOD_US);
+
+	/* And then wait an additional eight frame periods for it to be sent */
+	timeout = FRAME_PERIOD_US * 8;
+	do {
+		udelay(1);
+		v = readl(aaci->base + AACI_SLFR);
+	} while ((v & SLFR_1TXB) && --timeout);
+
+	if (v & SLFR_1TXB) {
+		dev_err(&aaci->dev->dev, "timeout on slot 1 TX busy\n");
+		v = ~0;
+		goto out;
+	}
+
+	/* Now wait for the response frame */
+	udelay(FRAME_PERIOD_US);
+
+	/* And then wait an additional eight frame periods for data */
+	timeout = FRAME_PERIOD_US * 8;
+	do {
+		udelay(1);
+		cond_resched();
+		v = readl(aaci->base + AACI_SLFR) & (SLFR_1RXV|SLFR_2RXV);
+	} while ((v != (SLFR_1RXV|SLFR_2RXV)) && --timeout);
+
+	if (v != (SLFR_1RXV|SLFR_2RXV)) {
+		dev_err(&aaci->dev->dev, "timeout on RX valid\n");
+		v = ~0;
+		goto out;
+	}
+
+	do {
+		v = readl(aaci->base + AACI_SL1RX) >> 12;
+		if (v == reg) {
+			v = readl(aaci->base + AACI_SL2RX) >> 4;
+			break;
+		} else if (--retries) {
+			dev_warn(&aaci->dev->dev,
+				 "ac97 read back fail.  retry\n");
+			continue;
+		} else {
+			dev_warn(&aaci->dev->dev,
+				"wrong ac97 register read back (%x != %x)\n",
+				v, reg);
+			v = ~0;
+		}
+	} while (retries);
+ out:
+	mutex_unlock(&aaci->ac97_sem);
+	return v;
+}
+
+static inline void
+aaci_chan_wait_ready(struct aaci_runtime *aacirun, unsigned long mask)
+{
+	u32 val;
+	int timeout = 5000;
+
+	do {
+		udelay(1);
+		val = readl(aacirun->base + AACI_SR);
+	} while (val & mask && timeout--);
+}
+
+
+
+/*
+ * Interrupt support.
+ */
+static void aaci_fifo_irq(struct aaci *aaci, int channel, u32 mask)
+{
+	if (mask & ISR_ORINTR) {
+		dev_warn(&aaci->dev->dev, "RX overrun on chan %d\n", channel);
+		writel(ICLR_RXOEC1 << channel, aaci->base + AACI_INTCLR);
+	}
+
+	if (mask & ISR_RXTOINTR) {
+		dev_warn(&aaci->dev->dev, "RX timeout on chan %d\n", channel);
+		writel(ICLR_RXTOFEC1 << channel, aaci->base + AACI_INTCLR);
+	}
+
+	if (mask & ISR_RXINTR) {
+		struct aaci_runtime *aacirun = &aaci->capture;
+		bool period_elapsed = false;
+		void *ptr;
+
+		if (!aacirun->substream || !aacirun->start) {
+			dev_warn(&aaci->dev->dev, "RX interrupt???\n");
+			writel(0, aacirun->base + AACI_IE);
+			return;
+		}
+
+		spin_lock(&aacirun->lock);
+
+		ptr = aacirun->ptr;
+		do {
+			unsigned int len = aacirun->fifo_bytes;
+			u32 val;
+
+			if (aacirun->bytes <= 0) {
+				aacirun->bytes += aacirun->period;
+				period_elapsed = true;
+			}
+			if (!(aacirun->cr & CR_EN))
+				break;
+
+			val = readl(aacirun->base + AACI_SR);
+			if (!(val & SR_RXHF))
+				break;
+			if (!(val & SR_RXFF))
+				len >>= 1;
+
+			aacirun->bytes -= len;
+
+			/* reading 16 bytes at a time */
+			for( ; len > 0; len -= 16) {
+				asm(
+					"ldmia	%1, {r0, r1, r2, r3}\n\t"
+					"stmia	%0!, {r0, r1, r2, r3}"
+					: "+r" (ptr)
+					: "r" (aacirun->fifo)
+					: "r0", "r1", "r2", "r3", "cc");
+
+				if (ptr >= aacirun->end)
+					ptr = aacirun->start;
+			}
+		} while(1);
+
+		aacirun->ptr = ptr;
+
+		spin_unlock(&aacirun->lock);
+
+		if (period_elapsed)
+			snd_pcm_period_elapsed(aacirun->substream);
+	}
+
+	if (mask & ISR_URINTR) {
+		dev_dbg(&aaci->dev->dev, "TX underrun on chan %d\n", channel);
+		writel(ICLR_TXUEC1 << channel, aaci->base + AACI_INTCLR);
+	}
+
+	if (mask & ISR_TXINTR) {
+		struct aaci_runtime *aacirun = &aaci->playback;
+		bool period_elapsed = false;
+		void *ptr;
+
+		if (!aacirun->substream || !aacirun->start) {
+			dev_warn(&aaci->dev->dev, "TX interrupt???\n");
+			writel(0, aacirun->base + AACI_IE);
+			return;
+		}
+
+		spin_lock(&aacirun->lock);
+
+		ptr = aacirun->ptr;
+		do {
+			unsigned int len = aacirun->fifo_bytes;
+			u32 val;
+
+			if (aacirun->bytes <= 0) {
+				aacirun->bytes += aacirun->period;
+				period_elapsed = true;
+			}
+			if (!(aacirun->cr & CR_EN))
+				break;
+
+			val = readl(aacirun->base + AACI_SR);
+			if (!(val & SR_TXHE))
+				break;
+			if (!(val & SR_TXFE))
+				len >>= 1;
+
+			aacirun->bytes -= len;
+
+			/* writing 16 bytes at a time */
+			for ( ; len > 0; len -= 16) {
+				asm(
+					"ldmia	%0!, {r0, r1, r2, r3}\n\t"
+					"stmia	%1, {r0, r1, r2, r3}"
+					: "+r" (ptr)
+					: "r" (aacirun->fifo)
+					: "r0", "r1", "r2", "r3", "cc");
+
+				if (ptr >= aacirun->end)
+					ptr = aacirun->start;
+			}
+		} while (1);
+
+		aacirun->ptr = ptr;
+
+		spin_unlock(&aacirun->lock);
+
+		if (period_elapsed)
+			snd_pcm_period_elapsed(aacirun->substream);
+	}
+}
+
+static irqreturn_t aaci_irq(int irq, void *devid)
+{
+	struct aaci *aaci = devid;
+	u32 mask;
+	int i;
+
+	mask = readl(aaci->base + AACI_ALLINTS);
+	if (mask) {
+		u32 m = mask;
+		for (i = 0; i < 4; i++, m >>= 7) {
+			if (m & 0x7f) {
+				aaci_fifo_irq(aaci, i, m);
+			}
+		}
+	}
+
+	return mask ? IRQ_HANDLED : IRQ_NONE;
+}
+
+
+
+/*
+ * ALSA support.
+ */
+static struct snd_pcm_hardware aaci_hw_info = {
+	.info			= SNDRV_PCM_INFO_MMAP |
+				  SNDRV_PCM_INFO_MMAP_VALID |
+				  SNDRV_PCM_INFO_INTERLEAVED |
+				  SNDRV_PCM_INFO_BLOCK_TRANSFER |
+				  SNDRV_PCM_INFO_RESUME,
+
+	/*
+	 * ALSA doesn't support 18-bit or 20-bit packed into 32-bit
+	 * words.  It also doesn't support 12-bit at all.
+	 */
+	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
+
+	/* rates are setup from the AC'97 codec */
+	.channels_min		= 2,
+	.channels_max		= 2,
+	.buffer_bytes_max	= 64 * 1024,
+	.period_bytes_min	= 256,
+	.period_bytes_max	= PAGE_SIZE,
+	.periods_min		= 4,
+	.periods_max		= PAGE_SIZE / 16,
+};
+
+/*
+ * We can support two and four channel audio.  Unfortunately
+ * six channel audio requires a non-standard channel ordering:
+ *   2 -> FL(3), FR(4)
+ *   4 -> FL(3), FR(4), SL(7), SR(8)
+ *   6 -> FL(3), FR(4), SL(7), SR(8), C(6), LFE(9) (required)
+ *        FL(3), FR(4), C(6), SL(7), SR(8), LFE(9) (actual)
+ * This requires an ALSA configuration file to correct.
+ */
+static int aaci_rule_channels(struct snd_pcm_hw_params *p,
+	struct snd_pcm_hw_rule *rule)
+{
+	static unsigned int channel_list[] = { 2, 4, 6 };
+	struct aaci *aaci = rule->private;
+	unsigned int mask = 1 << 0, slots;
+
+	/* pcms[0] is the our 5.1 PCM instance. */
+	slots = aaci->ac97_bus->pcms[0].r[0].slots;
+	if (slots & (1 << AC97_SLOT_PCM_SLEFT)) {
+		mask |= 1 << 1;
+		if (slots & (1 << AC97_SLOT_LFE))
+			mask |= 1 << 2;
+	}
+
+	return snd_interval_list(hw_param_interval(p, rule->var),
+				 ARRAY_SIZE(channel_list), channel_list, mask);
+}
+
+static int aaci_pcm_open(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct aaci *aaci = substream->private_data;
+	struct aaci_runtime *aacirun;
+	int ret = 0;
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		aacirun = &aaci->playback;
+	} else {
+		aacirun = &aaci->capture;
+	}
+
+	aacirun->substream = substream;
+	runtime->private_data = aacirun;
+	runtime->hw = aaci_hw_info;
+	runtime->hw.rates = aacirun->pcm->rates;
+	snd_pcm_limit_hw_rates(runtime);
+
+	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
+		runtime->hw.channels_max = 6;
+
+		/* Add rule describing channel dependency. */
+		ret = snd_pcm_hw_rule_add(substream->runtime, 0,
+					  SNDRV_PCM_HW_PARAM_CHANNELS,
+					  aaci_rule_channels, aaci,
+					  SNDRV_PCM_HW_PARAM_CHANNELS, -1);
+		if (ret)
+			return ret;
+
+		if (aacirun->pcm->r[1].slots)
+			snd_ac97_pcm_double_rate_rules(runtime);
+	}
+
+	/*
+	 * ALSA wants the byte-size of the FIFOs.  As we only support
+	 * 16-bit samples, this is twice the FIFO depth irrespective
+	 * of whether it's in compact mode or not.
+	 */
+	runtime->hw.fifo_size = aaci->fifo_depth * 2;
+
+	mutex_lock(&aaci->irq_lock);
+	if (!aaci->users++) {
+		ret = request_irq(aaci->dev->irq[0], aaci_irq,
+			   IRQF_SHARED, DRIVER_NAME, aaci);
+		if (ret != 0)
+			aaci->users--;
+	}
+	mutex_unlock(&aaci->irq_lock);
+
+	return ret;
+}
+
+
+/*
+ * Common ALSA stuff
+ */
+static int aaci_pcm_close(struct snd_pcm_substream *substream)
+{
+	struct aaci *aaci = substream->private_data;
+	struct aaci_runtime *aacirun = substream->runtime->private_data;
+
+	WARN_ON(aacirun->cr & CR_EN);
+
+	aacirun->substream = NULL;
+
+	mutex_lock(&aaci->irq_lock);
+	if (!--aaci->users)
+		free_irq(aaci->dev->irq[0], aaci);
+	mutex_unlock(&aaci->irq_lock);
+
+	return 0;
+}
+
+static int aaci_pcm_hw_free(struct snd_pcm_substream *substream)
+{
+	struct aaci_runtime *aacirun = substream->runtime->private_data;
+
+	/*
+	 * This must not be called with the device enabled.
+	 */
+	WARN_ON(aacirun->cr & CR_EN);
+
+	if (aacirun->pcm_open)
+		snd_ac97_pcm_close(aacirun->pcm);
+	aacirun->pcm_open = 0;
+
+	/*
+	 * Clear out the DMA and any allocated buffers.
+	 */
+	snd_pcm_lib_free_pages(substream);
+
+	return 0;
+}
+
+/* Channel to slot mask */
+static const u32 channels_to_slotmask[] = {
+	[2] = CR_SL3 | CR_SL4,
+	[4] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8,
+	[6] = CR_SL3 | CR_SL4 | CR_SL7 | CR_SL8 | CR_SL6 | CR_SL9,
+};
+
+static int aaci_pcm_hw_params(struct snd_pcm_substream *substream,
+			      struct snd_pcm_hw_params *params)
+{
+	struct aaci_runtime *aacirun = substream->runtime->private_data;
+	unsigned int channels = params_channels(params);
+	unsigned int rate = params_rate(params);
+	int dbl = rate > 48000;
+	int err;
+
+	aaci_pcm_hw_free(substream);
+	if (aacirun->pcm_open) {
+		snd_ac97_pcm_close(aacirun->pcm);
+		aacirun->pcm_open = 0;
+	}
+
+	/* channels is already limited to 2, 4, or 6 by aaci_rule_channels */
+	if (dbl && channels != 2)
+		return -EINVAL;
+
+	err = snd_pcm_lib_malloc_pages(substream,
+				       params_buffer_bytes(params));
+	if (err >= 0) {
+		struct aaci *aaci = substream->private_data;
+
+		err = snd_ac97_pcm_open(aacirun->pcm, rate, channels,
+					aacirun->pcm->r[dbl].slots);
+
+		aacirun->pcm_open = err == 0;
+		aacirun->cr = CR_FEN | CR_COMPACT | CR_SZ16;
+		aacirun->cr |= channels_to_slotmask[channels + dbl * 2];
+
+		/*
+		 * fifo_bytes is the number of bytes we transfer to/from
+		 * the FIFO, including padding.  So that's x4.  As we're
+		 * in compact mode, the FIFO is half the size.
+		 */
+		aacirun->fifo_bytes = aaci->fifo_depth * 4 / 2;
+	}
+
+	return err;
+}
+
+static int aaci_pcm_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct aaci_runtime *aacirun = runtime->private_data;
+
+	aacirun->period	= snd_pcm_lib_period_bytes(substream);
+	aacirun->start	= runtime->dma_area;
+	aacirun->end	= aacirun->start + snd_pcm_lib_buffer_bytes(substream);
+	aacirun->ptr	= aacirun->start;
+	aacirun->bytes	= aacirun->period;
+
+	return 0;
+}
+
+static snd_pcm_uframes_t aaci_pcm_pointer(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct aaci_runtime *aacirun = runtime->private_data;
+	ssize_t bytes = aacirun->ptr - aacirun->start;
+
+	return bytes_to_frames(runtime, bytes);
+}
+
+
+/*
+ * Playback specific ALSA stuff
+ */
+static void aaci_pcm_playback_stop(struct aaci_runtime *aacirun)
+{
+	u32 ie;
+
+	ie = readl(aacirun->base + AACI_IE);
+	ie &= ~(IE_URIE|IE_TXIE);
+	writel(ie, aacirun->base + AACI_IE);
+	aacirun->cr &= ~CR_EN;
+	aaci_chan_wait_ready(aacirun, SR_TXB);
+	writel(aacirun->cr, aacirun->base + AACI_TXCR);
+}
+
+static void aaci_pcm_playback_start(struct aaci_runtime *aacirun)
+{
+	u32 ie;
+
+	aaci_chan_wait_ready(aacirun, SR_TXB);
+	aacirun->cr |= CR_EN;
+
+	ie = readl(aacirun->base + AACI_IE);
+	ie |= IE_URIE | IE_TXIE;
+	writel(ie, aacirun->base + AACI_IE);
+	writel(aacirun->cr, aacirun->base + AACI_TXCR);
+}
+
+static int aaci_pcm_playback_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct aaci_runtime *aacirun = substream->runtime->private_data;
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&aacirun->lock, flags);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		aaci_pcm_playback_start(aacirun);
+		break;
+
+	case SNDRV_PCM_TRIGGER_RESUME:
+		aaci_pcm_playback_start(aacirun);
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+		aaci_pcm_playback_stop(aacirun);
+		break;
+
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+		aaci_pcm_playback_stop(aacirun);
+		break;
+
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		break;
+
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		break;
+
+	default:
+		ret = -EINVAL;
+	}
+
+	spin_unlock_irqrestore(&aacirun->lock, flags);
+
+	return ret;
+}
+
+static struct snd_pcm_ops aaci_playback_ops = {
+	.open		= aaci_pcm_open,
+	.close		= aaci_pcm_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= aaci_pcm_hw_params,
+	.hw_free	= aaci_pcm_hw_free,
+	.prepare	= aaci_pcm_prepare,
+	.trigger	= aaci_pcm_playback_trigger,
+	.pointer	= aaci_pcm_pointer,
+};
+
+static void aaci_pcm_capture_stop(struct aaci_runtime *aacirun)
+{
+	u32 ie;
+
+	aaci_chan_wait_ready(aacirun, SR_RXB);
+
+	ie = readl(aacirun->base + AACI_IE);
+	ie &= ~(IE_ORIE | IE_RXIE);
+	writel(ie, aacirun->base+AACI_IE);
+
+	aacirun->cr &= ~CR_EN;
+
+	writel(aacirun->cr, aacirun->base + AACI_RXCR);
+}
+
+static void aaci_pcm_capture_start(struct aaci_runtime *aacirun)
+{
+	u32 ie;
+
+	aaci_chan_wait_ready(aacirun, SR_RXB);
+
+#ifdef DEBUG
+	/* RX Timeout value: bits 28:17 in RXCR */
+	aacirun->cr |= 0xf << 17;
+#endif
+
+	aacirun->cr |= CR_EN;
+	writel(aacirun->cr, aacirun->base + AACI_RXCR);
+
+	ie = readl(aacirun->base + AACI_IE);
+	ie |= IE_ORIE |IE_RXIE; // overrun and rx interrupt -- half full
+	writel(ie, aacirun->base + AACI_IE);
+}
+
+static int aaci_pcm_capture_trigger(struct snd_pcm_substream *substream, int cmd)
+{
+	struct aaci_runtime *aacirun = substream->runtime->private_data;
+	unsigned long flags;
+	int ret = 0;
+
+	spin_lock_irqsave(&aacirun->lock, flags);
+
+	switch (cmd) {
+	case SNDRV_PCM_TRIGGER_START:
+		aaci_pcm_capture_start(aacirun);
+		break;
+
+	case SNDRV_PCM_TRIGGER_RESUME:
+		aaci_pcm_capture_start(aacirun);
+		break;
+
+	case SNDRV_PCM_TRIGGER_STOP:
+		aaci_pcm_capture_stop(aacirun);
+		break;
+
+	case SNDRV_PCM_TRIGGER_SUSPEND:
+		aaci_pcm_capture_stop(aacirun);
+		break;
+
+	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
+		break;
+
+	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
+		break;
+
+	default:
+		ret = -EINVAL;
+	}
+
+	spin_unlock_irqrestore(&aacirun->lock, flags);
+
+	return ret;
+}
+
+static int aaci_pcm_capture_prepare(struct snd_pcm_substream *substream)
+{
+	struct snd_pcm_runtime *runtime = substream->runtime;
+	struct aaci *aaci = substream->private_data;
+
+	aaci_pcm_prepare(substream);
+
+	/* allow changing of sample rate */
+	aaci_ac97_write(aaci->ac97, AC97_EXTENDED_STATUS, 0x0001); /* VRA */
+	aaci_ac97_write(aaci->ac97, AC97_PCM_LR_ADC_RATE, runtime->rate);
+	aaci_ac97_write(aaci->ac97, AC97_PCM_MIC_ADC_RATE, runtime->rate);
+
+	/* Record select: Mic: 0, Aux: 3, Line: 4 */
+	aaci_ac97_write(aaci->ac97, AC97_REC_SEL, 0x0404);
+
+	return 0;
+}
+
+static struct snd_pcm_ops aaci_capture_ops = {
+	.open		= aaci_pcm_open,
+	.close		= aaci_pcm_close,
+	.ioctl		= snd_pcm_lib_ioctl,
+	.hw_params	= aaci_pcm_hw_params,
+	.hw_free	= aaci_pcm_hw_free,
+	.prepare	= aaci_pcm_capture_prepare,
+	.trigger	= aaci_pcm_capture_trigger,
+	.pointer	= aaci_pcm_pointer,
+};
+
+/*
+ * Power Management.
+ */
+#ifdef CONFIG_PM
+static int aaci_do_suspend(struct snd_card *card)
+{
+	struct aaci *aaci = card->private_data;
+	snd_power_change_state(card, SNDRV_CTL_POWER_D3cold);
+	snd_pcm_suspend_all(aaci->pcm);
+	return 0;
+}
+
+static int aaci_do_resume(struct snd_card *card)
+{
+	snd_power_change_state(card, SNDRV_CTL_POWER_D0);
+	return 0;
+}
+
+static int aaci_suspend(struct device *dev)
+{
+	struct snd_card *card = dev_get_drvdata(dev);
+	return card ? aaci_do_suspend(card) : 0;
+}
+
+static int aaci_resume(struct device *dev)
+{
+	struct snd_card *card = dev_get_drvdata(dev);
+	return card ? aaci_do_resume(card) : 0;
+}
+
+static SIMPLE_DEV_PM_OPS(aaci_dev_pm_ops, aaci_suspend, aaci_resume);
+#define AACI_DEV_PM_OPS (&aaci_dev_pm_ops)
+#else
+#define AACI_DEV_PM_OPS NULL
+#endif
+
+
+static struct ac97_pcm ac97_defs[] = {
+	[0] = {	/* Front PCM */
+		.exclusive = 1,
+		.r = {
+			[0] = {
+				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
+					  (1 << AC97_SLOT_PCM_RIGHT) |
+					  (1 << AC97_SLOT_PCM_CENTER) |
+					  (1 << AC97_SLOT_PCM_SLEFT) |
+					  (1 << AC97_SLOT_PCM_SRIGHT) |
+					  (1 << AC97_SLOT_LFE),
+			},
+			[1] = {
+				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
+					  (1 << AC97_SLOT_PCM_RIGHT) |
+					  (1 << AC97_SLOT_PCM_LEFT_0) |
+					  (1 << AC97_SLOT_PCM_RIGHT_0),
+			},
+		},
+	},
+	[1] = {	/* PCM in */
+		.stream = 1,
+		.exclusive = 1,
+		.r = {
+			[0] = {
+				.slots	= (1 << AC97_SLOT_PCM_LEFT) |
+					  (1 << AC97_SLOT_PCM_RIGHT),
+			},
+		},
+	},
+	[2] = {	/* Mic in */
+		.stream = 1,
+		.exclusive = 1,
+		.r = {
+			[0] = {
+				.slots	= (1 << AC97_SLOT_MIC),
+			},
+		},
+	}
+};
+
+static struct snd_ac97_bus_ops aaci_bus_ops = {
+	.write	= aaci_ac97_write,
+	.read	= aaci_ac97_read,
+};
+
+static int aaci_probe_ac97(struct aaci *aaci)
+{
+	struct snd_ac97_template ac97_template;
+	struct snd_ac97_bus *ac97_bus;
+	struct snd_ac97 *ac97;
+	int ret;
+
+	/*
+	 * Assert AACIRESET for 2us
+	 */
+	writel(0, aaci->base + AACI_RESET);
+	udelay(2);
+	writel(RESET_NRST, aaci->base + AACI_RESET);
+
+	/*
+	 * Give the AC'97 codec more than enough time
+	 * to wake up. (42us = ~2 frames at 48kHz.)
+	 */
+	udelay(FRAME_PERIOD_US * 2);
+
+	ret = snd_ac97_bus(aaci->card, 0, &aaci_bus_ops, aaci, &ac97_bus);
+	if (ret)
+		goto out;
+
+	ac97_bus->clock = 48000;
+	aaci->ac97_bus = ac97_bus;
+
+	memset(&ac97_template, 0, sizeof(struct snd_ac97_template));
+	ac97_template.private_data = aaci;
+	ac97_template.num = 0;
+	ac97_template.scaps = AC97_SCAP_SKIP_MODEM;
+
+	ret = snd_ac97_mixer(ac97_bus, &ac97_template, &ac97);
+	if (ret)
+		goto out;
+	aaci->ac97 = ac97;
+
+	/*
+	 * Disable AC97 PC Beep input on audio codecs.
+	 */
+	if (ac97_is_audio(ac97))
+		snd_ac97_write_cache(ac97, AC97_PC_BEEP, 0x801e);
+
+	ret = snd_ac97_pcm_assign(ac97_bus, ARRAY_SIZE(ac97_defs), ac97_defs);
+	if (ret)
+		goto out;
+
+	aaci->playback.pcm = &ac97_bus->pcms[0];
+	aaci->capture.pcm  = &ac97_bus->pcms[1];
+
+ out:
+	return ret;
+}
+
+static void aaci_free_card(struct snd_card *card)
+{
+	struct aaci *aaci = card->private_data;
+
+	iounmap(aaci->base);
+}
+
+static struct aaci *aaci_init_card(struct amba_device *dev)
+{
+	struct aaci *aaci;
+	struct snd_card *card;
+	int err;
+
+	err = snd_card_new(&dev->dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
+			   THIS_MODULE, sizeof(struct aaci), &card);
+	if (err < 0)
+		return NULL;
+
+	card->private_free = aaci_free_card;
+
+	strlcpy(card->driver, DRIVER_NAME, sizeof(card->driver));
+	strlcpy(card->shortname, "ARM AC'97 Interface", sizeof(card->shortname));
+	snprintf(card->longname, sizeof(card->longname),
+		 "%s PL%03x rev%u at 0x%08llx, irq %d",
+		 card->shortname, amba_part(dev), amba_rev(dev),
+		 (unsigned long long)dev->res.start, dev->irq[0]);
+
+	aaci = card->private_data;
+	mutex_init(&aaci->ac97_sem);
+	mutex_init(&aaci->irq_lock);
+	aaci->card = card;
+	aaci->dev = dev;
+
+	/* Set MAINCR to allow slot 1 and 2 data IO */
+	aaci->maincr = MAINCR_IE | MAINCR_SL1RXEN | MAINCR_SL1TXEN |
+		       MAINCR_SL2RXEN | MAINCR_SL2TXEN;
+
+	return aaci;
+}
+
+static int aaci_init_pcm(struct aaci *aaci)
+{
+	struct snd_pcm *pcm;
+	int ret;
+
+	ret = snd_pcm_new(aaci->card, "AACI AC'97", 0, 1, 1, &pcm);
+	if (ret == 0) {
+		aaci->pcm = pcm;
+		pcm->private_data = aaci;
+		pcm->info_flags = 0;
+
+		strlcpy(pcm->name, DRIVER_NAME, sizeof(pcm->name));
+
+		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &aaci_playback_ops);
+		snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &aaci_capture_ops);
+		snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
+						      NULL, 0, 64 * 1024);
+	}
+
+	return ret;
+}
+
+static unsigned int aaci_size_fifo(struct aaci *aaci)
+{
+	struct aaci_runtime *aacirun = &aaci->playback;
+	int i;
+
+	/*
+	 * Enable the channel, but don't assign it to any slots, so
+	 * it won't empty onto the AC'97 link.
+	 */
+	writel(CR_FEN | CR_SZ16 | CR_EN, aacirun->base + AACI_TXCR);
+
+	for (i = 0; !(readl(aacirun->base + AACI_SR) & SR_TXFF) && i < 4096; i++)
+		writel(0, aacirun->fifo);
+
+	writel(0, aacirun->base + AACI_TXCR);
+
+	/*
+	 * Re-initialise the AACI after the FIFO depth test, to
+	 * ensure that the FIFOs are empty.  Unfortunately, merely
+	 * disabling the channel doesn't clear the FIFO.
+	 */
+	writel(aaci->maincr & ~MAINCR_IE, aaci->base + AACI_MAINCR);
+	readl(aaci->base + AACI_MAINCR);
+	udelay(1);
+	writel(aaci->maincr, aaci->base + AACI_MAINCR);
+
+	/*
+	 * If we hit 4096 entries, we failed.  Go back to the specified
+	 * fifo depth.
+	 */
+	if (i == 4096)
+		i = 8;
+
+	return i;
+}
+
+static int aaci_probe(struct amba_device *dev,
+		      const struct amba_id *id)
+{
+	struct aaci *aaci;
+	int ret, i;
+
+	ret = amba_request_regions(dev, NULL);
+	if (ret)
+		return ret;
+
+	aaci = aaci_init_card(dev);
+	if (!aaci) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	aaci->base = ioremap(dev->res.start, resource_size(&dev->res));
+	if (!aaci->base) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	/*
+	 * Playback uses AACI channel 0
+	 */
+	spin_lock_init(&aaci->playback.lock);
+	aaci->playback.base = aaci->base + AACI_CSCH1;
+	aaci->playback.fifo = aaci->base + AACI_DR1;
+
+	/*
+	 * Capture uses AACI channel 0
+	 */
+	spin_lock_init(&aaci->capture.lock);
+	aaci->capture.base = aaci->base + AACI_CSCH1;
+	aaci->capture.fifo = aaci->base + AACI_DR1;
+
+	for (i = 0; i < 4; i++) {
+		void __iomem *base = aaci->base + i * 0x14;
+
+		writel(0, base + AACI_IE);
+		writel(0, base + AACI_TXCR);
+		writel(0, base + AACI_RXCR);
+	}
+
+	writel(0x1fff, aaci->base + AACI_INTCLR);
+	writel(aaci->maincr, aaci->base + AACI_MAINCR);
+	/*
+	 * Fix: ac97 read back fail errors by reading
+	 * from any arbitrary aaci register.
+	 */
+	readl(aaci->base + AACI_CSCH1);
+	ret = aaci_probe_ac97(aaci);
+	if (ret)
+		goto out;
+
+	/*
+	 * Size the FIFOs (must be multiple of 16).
+	 * This is the number of entries in the FIFO.
+	 */
+	aaci->fifo_depth = aaci_size_fifo(aaci);
+	if (aaci->fifo_depth & 15) {
+		printk(KERN_WARNING "AACI: FIFO depth %d not supported\n",
+		       aaci->fifo_depth);
+		ret = -ENODEV;
+		goto out;
+	}
+
+	ret = aaci_init_pcm(aaci);
+	if (ret)
+		goto out;
+
+	ret = snd_card_register(aaci->card);
+	if (ret == 0) {
+		dev_info(&dev->dev, "%s\n", aaci->card->longname);
+		dev_info(&dev->dev, "FIFO %u entries\n", aaci->fifo_depth);
+		amba_set_drvdata(dev, aaci->card);
+		return ret;
+	}
+
+ out:
+	if (aaci)
+		snd_card_free(aaci->card);
+	amba_release_regions(dev);
+	return ret;
+}
+
+static int aaci_remove(struct amba_device *dev)
+{
+	struct snd_card *card = amba_get_drvdata(dev);
+
+	if (card) {
+		struct aaci *aaci = card->private_data;
+		writel(0, aaci->base + AACI_MAINCR);
+
+		snd_card_free(card);
+		amba_release_regions(dev);
+	}
+
+	return 0;
+}
+
+static struct amba_id aaci_ids[] = {
+	{
+		.id	= 0x00041041,
+		.mask	= 0x000fffff,
+	},
+	{ 0, 0 },
+};
+
+MODULE_DEVICE_TABLE(amba, aaci_ids);
+
+static struct amba_driver aaci_driver = {
+	.drv		= {
+		.name	= DRIVER_NAME,
+		.pm	= AACI_DEV_PM_OPS,
+	},
+	.probe		= aaci_probe,
+	.remove		= aaci_remove,
+	.id_table	= aaci_ids,
+};
+
+module_amba_driver(aaci_driver);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("ARM PrimeCell PL041 Advanced Audio CODEC Interface driver");