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path: root/packages/linux/linux-2.6.18/at32-dac-oss-driver.patch
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From nobody Mon Sep 17 00:00:00 2001
From: Håvard Skinnemoen <hskinnemoen@atmel.com>
Date: Mon Apr 3 17:38:29 2006 +0200
Subject: [PATCH] OSS driver for the AT32 on-chip digital DAC

---

 sound/oss/Kconfig   |    4 
 sound/oss/Makefile  |    1 
 sound/oss/at32dac.c |  707 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 sound/oss/at32dac.h |   65 ++++
 4 files changed, 777 insertions(+)

Index: linux-2.6.18-avr32/sound/oss/Kconfig
===================================================================
--- linux-2.6.18-avr32.orig/sound/oss/Kconfig	2006-11-02 15:54:18.000000000 +0100
+++ linux-2.6.18-avr32/sound/oss/Kconfig	2006-11-02 15:56:20.000000000 +0100
@@ -869,3 +869,7 @@ config SOUND_SH_DAC_AUDIO_CHANNEL
 	int "DAC channel"
 	default "1"
 	depends on SOUND_SH_DAC_AUDIO
+
+config SOUND_AT32_DAC
+	tristate "Atmel AT32 On-chip DAC support"
+	depends on SOUND_PRIME && AVR32
Index: linux-2.6.18-avr32/sound/oss/Makefile
===================================================================
--- linux-2.6.18-avr32.orig/sound/oss/Makefile	2006-11-02 15:54:18.000000000 +0100
+++ linux-2.6.18-avr32/sound/oss/Makefile	2006-11-02 15:56:20.000000000 +0100
@@ -10,6 +10,7 @@ obj-$(CONFIG_SOUND_CS4232)	+= cs4232.o a
 
 # Please leave it as is, cause the link order is significant !
 
+obj-$(CONFIG_SOUND_AT32_DAC)	+= at32dac.o
 obj-$(CONFIG_SOUND_SH_DAC_AUDIO)	+= sh_dac_audio.o
 obj-$(CONFIG_SOUND_HAL2)	+= hal2.o
 obj-$(CONFIG_SOUND_AEDSP16)	+= aedsp16.o
Index: linux-2.6.18-avr32/sound/oss/at32dac.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.18-avr32/sound/oss/at32dac.c	2006-11-02 15:56:20.000000000 +0100
@@ -0,0 +1,707 @@
+/*
+ * OSS Sound Driver for the Atmel AT32 on-chip DAC.
+ *
+ * Copyright (C) 2006 Atmel Corporation
+ *
+ * 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.
+ */
+#include <linux/clk.h>
+#include <linux/dma-mapping.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/sound.h>
+#include <linux/soundcard.h>
+
+#include <asm/byteorder.h>
+#include <asm/dma-controller.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+
+/* We want to use the "bizarre" swap-bytes-in-each-halfword macro */
+#include <linux/byteorder/swabb.h>
+
+#include "at32dac.h"
+
+#define DMA_BUFFER_SIZE	32768
+#define DMA_PERIOD_SHIFT 10
+#define DMA_PERIOD_SIZE (1 << DMA_PERIOD_SHIFT)
+#define DMA_WRITE_THRESHOLD DMA_PERIOD_SIZE
+
+struct sound_settings {
+	unsigned int format;
+	unsigned int channels;
+	unsigned int sample_rate;
+	/* log2(bytes per sample) */
+	unsigned int input_order;
+};
+
+struct at32_dac {
+	spinlock_t lock;
+	void __iomem *regs;
+
+	/* head and tail refer to number of words */
+	struct {
+		u32 *buf;
+		int head;
+		int tail;
+	} dma;
+
+	struct semaphore sem;
+	wait_queue_head_t write_wait;
+
+	/*
+	 * Read at most ucount bytes from ubuf, translate to 2-channel
+	 * signed 16-bit big endian format and write to the DMA buffer
+	 * as long as there is room left.  Return the number of bytes
+	 * successfully copied from ubuf, or -EFAULT if the first
+	 * sample from ubuf couldn't be read.  This function is not
+	 * called unless there is room for at least one sample (4
+	 * bytes) in the DMA buffer.
+	 */
+	int (*trans)(struct at32_dac *dac, const char __user *ubuf,
+		     size_t ucount);
+
+	struct sound_settings dsp_settings;
+	struct dma_request_cyclic req;
+
+	struct clk *mck;
+	struct platform_device *pdev;
+	int busy;
+	int playing;
+	int dev_dsp;
+};
+static struct at32_dac *the_dac;
+
+static inline unsigned int at32dac_get_head(struct at32_dac *dac)
+{
+	return dac->dma.head & ((DMA_BUFFER_SIZE / 4) - 1);
+}
+
+static inline unsigned int at32dac_get_tail(struct at32_dac *dac)
+{
+	return dac->dma.tail & ((DMA_BUFFER_SIZE / 4) - 1);
+}
+
+static inline unsigned int at32dac_dma_space(struct at32_dac *dac)
+{
+	unsigned int space;
+
+	space = ((dac->dma.tail - dac->dma.head - 1)
+		 & ((DMA_BUFFER_SIZE / 4) - 1));
+	return space;
+}
+
+static void at32dac_update_dma_tail(struct at32_dac *dac)
+{
+	dma_addr_t dma_addr;
+	unsigned int new_tail;
+
+	if (dac->playing) {
+		dma_addr = dma_get_current_pos(dac->req.req.dmac,
+					       dac->req.req.channel);
+		new_tail = (dma_addr - dac->req.buffer_start) / 4;
+		if (new_tail >= dac->dma.head
+		    && (dac->dma.tail < dac->dma.head
+			|| dac->dma.tail > new_tail))
+			printk(KERN_NOTICE "at32dac: underrun\n");
+		dac->dma.tail = new_tail;
+		pr_debug("update tail: 0x%x - 0x%x = %u\n",
+			 dma_addr, dac->req.buffer_start, dac->dma.tail);
+	}
+}
+
+static int at32dac_start_genclock(struct at32_dac *dac)
+{
+	unsigned int div;
+
+	div = ((clk_get_rate(boot_cpu_data.clk) + 256 * dac->dsp_settings.sample_rate)
+	       / (512 * dac->dsp_settings.sample_rate) - 1);
+	pr_debug("Real sample rate: %llu (div=%u)\n",
+		 boot_cpu_data.cpu_hz / (512 * (div + 1)), div);
+	writel((div << 8) | 0x16, (void __iomem *)(0xfff00060 + 4 * 6));
+
+	return 0;
+}
+
+static void at32dac_stop_genclock(struct at32_dac *dac)
+{
+	writel(0, (void __iomem *)(0xfff00060 + 4 * 6));
+}
+
+static int at32dac_start(struct at32_dac *dac)
+{
+	int ret;
+
+	if (dac->playing)
+		return 0;
+
+	memset(dac->dma.buf, 0, DMA_BUFFER_SIZE);
+
+	ret = at32dac_start_genclock(dac);
+	if (ret)
+		return ret;
+
+	ret = dma_prepare_request_cyclic(dac->req.req.dmac, &dac->req);
+	if (ret)
+		goto out_stop_genclock;
+
+	pr_debug("Starting DMA...\n");
+	ret = dma_start_request(dac->req.req.dmac, dac->req.req.channel);
+	if (ret)
+		goto out_stop_request;
+
+	dac_writel(dac, CTRL, DAC_BIT(EN));
+	dac->playing = 1;
+
+	return 0;
+
+out_stop_request:
+	dma_stop_request(dac->req.req.dmac,
+			 dac->req.req.channel);
+out_stop_genclock:
+	at32dac_stop_genclock(dac);
+	return ret;
+}
+
+static int at32dac_stop(struct at32_dac *dac)
+{
+	if (dac->playing) {
+		dma_stop_request(dac->req.req.dmac, dac->req.req.channel);
+		dac_writel(dac, DATA, 0);
+		dac_writel(dac, CTRL, 0);
+		dac->playing = 0;
+		at32dac_stop_genclock(dac);
+	}
+
+	return 0;
+}
+
+static int at32dac_dma_prepare(struct at32_dac *dac)
+{
+	dac->dma.buf = dma_alloc_coherent(&dac->pdev->dev, DMA_BUFFER_SIZE,
+					  &dac->req.buffer_start, GFP_KERNEL);
+	if (!dac->dma.buf)
+		return -ENOMEM;
+
+	dac->dma.head = dac->dma.tail = 0;
+	dac->req.periods = DMA_BUFFER_SIZE / DMA_PERIOD_SIZE;
+	dac->req.buffer_size = DMA_BUFFER_SIZE;
+
+	return 0;
+}
+
+static void at32dac_dma_cleanup(struct at32_dac *dac)
+{
+	if (dac->dma.buf)
+		dma_free_coherent(&dac->pdev->dev, DMA_BUFFER_SIZE,
+				  dac->dma.buf, dac->req.buffer_start);
+	dac->dma.buf = NULL;
+}
+
+static void at32dac_dma_block_complete(struct dma_request *req)
+{
+	struct dma_request_cyclic *creq = to_dma_request_cyclic(req);
+	struct at32_dac *dac = container_of(creq, struct at32_dac, req);
+
+	wake_up(&dac->write_wait);
+}
+
+static void at32dac_dma_error(struct dma_request *req)
+{
+	printk(KERN_ERR "at32dac: DMA error\n");
+}
+
+static irqreturn_t at32dac_interrupt(int irq, void *dev_id,
+				     struct pt_regs *regs)
+{
+	struct at32_dac *dac = dev_id;
+	u32 status;
+
+	status = dac_readl(dac, INT_STATUS);
+	if (status & DAC_BIT(UNDERRUN)) {
+		printk(KERN_ERR "at32dac: Underrun detected\n");
+		dac_writel(dac, INT_CLR, DAC_BIT(UNDERRUN));
+	} else {
+		printk(KERN_ERR "at32dac: Spurious interrupt: status=0x%x\n",
+		       status);
+		dac_writel(dac, INT_CLR, status);
+	}
+
+	return IRQ_HANDLED;
+}
+
+static ssize_t trans_s16be(struct at32_dac *dac, const char __user *ubuf,
+			   size_t ucount)
+{
+	ssize_t ret;
+
+	if (dac->dsp_settings.channels == 2) {
+		const u32 __user *up = (const u32 __user *)ubuf;
+		u32 sample;
+
+		for (ret = 0; ret < (ssize_t)(ucount - 3); ret += 4) {
+			if (!at32dac_dma_space(dac))
+				break;
+
+			if (unlikely(__get_user(sample, up++))) {
+				if (ret == 0)
+					ret = -EFAULT;
+				break;
+			}
+			dac->dma.buf[at32dac_get_head(dac)] = sample;
+			dac->dma.head++;
+		}
+	} else {
+		const u16 __user *up = (const u16 __user *)ubuf;
+		u16 sample;
+
+		for (ret = 0; ret < (ssize_t)(ucount - 1); ret += 2) {
+			if (!at32dac_dma_space(dac))
+				break;
+
+			if (unlikely(__get_user(sample, up++))) {
+				if (ret == 0)
+					ret = -EFAULT;
+				break;
+			}
+			dac->dma.buf[at32dac_get_head(dac)]
+				= (sample << 16) | sample;
+			dac->dma.head++;
+		}
+	}
+
+	return ret;
+}
+
+static ssize_t trans_s16le(struct at32_dac *dac, const char __user *ubuf,
+			   size_t ucount)
+{
+	ssize_t ret;
+
+	if (dac->dsp_settings.channels == 2) {
+		const u32 __user *up = (const u32 __user *)ubuf;
+		u32 sample;
+
+		for (ret = 0; ret < (ssize_t)(ucount - 3); ret += 4) {
+			if (!at32dac_dma_space(dac))
+				break;
+
+			if (unlikely(__get_user(sample, up++))) {
+				if (ret == 0)
+					ret = -EFAULT;
+				break;
+			}
+			/* Swap bytes in each halfword */
+			dac->dma.buf[at32dac_get_head(dac)] = swahb32(sample);
+			dac->dma.head++;
+		}
+	} else {
+		const u16 __user *up = (const u16 __user *)ubuf;
+		u16 sample;
+
+		for (ret = 0; ret < (ssize_t)(ucount - 1); ret += 2) {
+			if (!at32dac_dma_space(dac))
+				break;
+
+			if (unlikely(__get_user(sample, up++))) {
+				if (ret == 0)
+					ret = -EFAULT;
+				break;
+			}
+			sample = swab16(sample);
+			dac->dma.buf[at32dac_get_head(dac)]
+				= (sample << 16) | sample;
+			dac->dma.head++;
+		}
+	}
+
+	return ret;
+}
+
+static ssize_t at32dac_dma_translate_from_user(struct at32_dac *dac,
+					       const char __user *buffer,
+					       size_t count)
+{
+	/* At least one buffer must be available at this point */
+	pr_debug("at32dac: Copying %zu bytes from user...\n", count);
+
+	return dac->trans(dac, buffer, count);
+}
+
+static int at32dac_set_format(struct at32_dac *dac, int format)
+{
+	unsigned int order;
+
+	switch (format) {
+	case AFMT_S16_BE:
+		order = 1;
+		dac->trans = trans_s16be;
+		break;
+	case AFMT_S16_LE:
+		order = 1;
+		dac->trans = trans_s16le;
+		break;
+	default:
+		printk("at32dac: Unsupported format: %d\n", format);
+		return -EINVAL;
+	}
+
+	if (dac->dsp_settings.channels == 2)
+		order++;
+
+	dac->dsp_settings.input_order = order;
+	dac->dsp_settings.format = format;
+	return 0;
+}
+
+static ssize_t at32dac_dsp_write(struct file *file,
+				 const char __user *buffer,
+				 size_t count, loff_t *ppos)
+{
+	struct at32_dac *dac = file->private_data;
+	DECLARE_WAITQUEUE(wait, current);
+	unsigned int avail;
+	ssize_t copied;
+	ssize_t ret;
+
+	/* Avoid address space checking in the translation functions */
+	if (!access_ok(buffer, count, VERIFY_READ))
+		return -EFAULT;
+
+	down(&dac->sem);
+
+	if (!dac->dma.buf) {
+		ret = at32dac_dma_prepare(dac);
+		if (ret)
+			goto out;
+	}
+
+	add_wait_queue(&dac->write_wait, &wait);
+	ret = 0;
+	while (count > 0) {
+		do {
+			at32dac_update_dma_tail(dac);
+			avail = at32dac_dma_space(dac);
+			set_current_state(TASK_INTERRUPTIBLE);
+			if (avail >= DMA_WRITE_THRESHOLD)
+				break;
+
+			if (file->f_flags & O_NONBLOCK) {
+				if (!ret)
+					ret = -EAGAIN;
+				goto out;
+			}
+
+			pr_debug("Going to wait (avail = %u, count = %zu)\n",
+				 avail, count);
+
+			up(&dac->sem);
+			schedule();
+			if (signal_pending(current)) {
+				if (!ret)
+					ret = -ERESTARTSYS;
+				goto out_nosem;
+			}
+			down(&dac->sem);
+		} while (1);
+
+		copied = at32dac_dma_translate_from_user(dac, buffer, count);
+		if (copied < 0) {
+			if (!ret)
+				ret = -EFAULT;
+			goto out;
+		}
+
+		at32dac_start(dac);
+
+		count -= copied;
+		ret += copied;
+	}
+
+out:
+	up(&dac->sem);
+out_nosem:
+	remove_wait_queue(&dac->write_wait, &wait);
+	set_current_state(TASK_RUNNING);
+	return ret;
+}
+
+static int at32dac_dsp_ioctl(struct inode *inode, struct file *file,
+			     unsigned int cmd, unsigned long arg)
+{
+	struct at32_dac *dac = file->private_data;
+	int __user *up = (int __user *)arg;
+	struct audio_buf_info abinfo;
+	int val, ret;
+
+	switch (cmd) {
+	case OSS_GETVERSION:
+		return put_user(SOUND_VERSION, up);
+
+	case SNDCTL_DSP_SPEED:
+		if (get_user(val, up))
+			return -EFAULT;
+		if (val >= 0) {
+			at32dac_stop(dac);
+			dac->dsp_settings.sample_rate = val;
+		}
+		return put_user(dac->dsp_settings.sample_rate, up);
+
+	case SNDCTL_DSP_STEREO:
+		if (get_user(val, up))
+			return -EFAULT;
+		at32dac_stop(dac);
+		if (val && dac->dsp_settings.channels == 1)
+			dac->dsp_settings.input_order++;
+		else if (!val && dac->dsp_settings.channels != 1)
+			dac->dsp_settings.input_order--;
+		dac->dsp_settings.channels = val ? 2 : 1;
+		return 0;
+
+	case SNDCTL_DSP_CHANNELS:
+		if (get_user(val, up))
+			return -EFAULT;
+
+		if (val) {
+			if (val < 0 || val > 2)
+				return -EINVAL;
+
+			at32dac_stop(dac);
+			dac->dsp_settings.input_order
+				+= val - dac->dsp_settings.channels;
+			dac->dsp_settings.channels = val;
+		}
+		return put_user(val, (int *)arg);
+
+	case SNDCTL_DSP_GETFMTS:
+		return put_user(AFMT_S16_BE | AFMT_S16_BE, up);
+
+	case SNDCTL_DSP_SETFMT:
+		if (get_user(val, up))
+			return -EFAULT;
+
+		if (val == AFMT_QUERY) {
+			val = dac->dsp_settings.format;
+		} else {
+			ret = at32dac_set_format(dac, val);
+			if (ret)
+				return ret;
+		}
+		return put_user(val, up);
+
+	case SNDCTL_DSP_GETOSPACE:
+		at32dac_update_dma_tail(dac);
+		abinfo.fragsize = ((1 << dac->dsp_settings.input_order)
+				   * (DMA_PERIOD_SIZE / 4));
+		abinfo.bytes = (at32dac_dma_space(dac)
+				<< dac->dsp_settings.input_order);
+		abinfo.fragstotal = ((DMA_BUFFER_SIZE * 4)
+				     >> (DMA_PERIOD_SHIFT
+					 + dac->dsp_settings.input_order));
+		abinfo.fragments = ((abinfo.bytes
+				     >> dac->dsp_settings.input_order)
+				    / (DMA_PERIOD_SIZE / 4));
+		pr_debug("fragments=%d  fragstotal=%d  fragsize=%d bytes=%d\n",
+			 abinfo.fragments, abinfo.fragstotal, abinfo.fragsize,
+			 abinfo.bytes);
+		return copy_to_user(up, &abinfo, sizeof(abinfo)) ? -EFAULT : 0;
+
+	default:
+		printk("at32dac: Unimplemented ioctl cmd: 0x%x\n", cmd);
+		return -EINVAL;
+	}
+}
+
+static int at32dac_dsp_open(struct inode *inode, struct file *file)
+{
+	struct at32_dac *dac = the_dac;
+	int ret;
+
+	if (file->f_mode & FMODE_READ)
+		return -ENXIO;
+
+	down(&dac->sem);
+	ret = -EBUSY;
+	if (dac->busy)
+		goto out;
+
+	dac->dma.head = dac->dma.tail = 0;
+
+	/* FIXME: What are the correct defaults?  */
+	dac->dsp_settings.format = AFMT_S16_BE;
+	dac->dsp_settings.channels = 2;
+	dac->dsp_settings.sample_rate = 8000;
+	dac->dsp_settings.input_order = 2;
+
+	file->private_data = dac;
+	dac->busy = 1;
+
+	ret = 0;
+
+out:
+	up(&dac->sem);
+	return ret;
+}
+
+static int at32dac_dsp_release(struct inode *inode, struct file *file)
+{
+	struct at32_dac *dac = file->private_data;
+
+	down(&dac->sem);
+
+	at32dac_stop(dac);
+	at32dac_dma_cleanup(dac);
+	dac->busy = 0;
+
+	up(&dac->sem);
+
+	return 0;
+}
+
+static struct file_operations at32dac_dsp_fops = {
+	.owner		= THIS_MODULE,
+	.llseek		= no_llseek,
+	.write		= at32dac_dsp_write,
+	.ioctl		= at32dac_dsp_ioctl,
+	.open		= at32dac_dsp_open,
+	.release	= at32dac_dsp_release,
+};
+
+static int __devinit at32dac_probe(struct platform_device *pdev)
+{
+	struct at32_dac *dac;
+	struct resource *regs;
+	struct clk *mck;
+	int irq;
+	int ret;
+
+	if (the_dac)
+		return -EBUSY;
+
+	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!regs)
+		return -ENXIO;
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return irq;
+
+	mck = clk_get(&pdev->dev, "mck");
+	if (IS_ERR(mck))
+		return PTR_ERR(mck);
+	clk_enable(mck);
+
+	ret = -ENOMEM;
+	dac = kzalloc(sizeof(struct at32_dac), GFP_KERNEL);
+	if (!dac)
+		goto out_disable_clk;
+
+	spin_lock_init(&dac->lock);
+	init_MUTEX(&dac->sem);
+	init_waitqueue_head(&dac->write_wait);
+	dac->pdev = pdev;
+	dac->mck = mck;
+
+	dac->regs = ioremap(regs->start, regs->end - regs->start + 1);
+	if (!dac->regs)
+		goto out_free_dac;
+
+	ret = request_irq(irq, at32dac_interrupt, 0, "dac", dac);
+	if (ret)
+		goto out_unmap_regs;
+
+	/* FIXME */
+	dac->req.req.dmac = find_dma_controller(0);
+	if (!dac->req.req.dmac)
+		goto out_free_irq;
+
+	ret = dma_alloc_channel(dac->req.req.dmac);
+	if (ret < 0)
+		goto out_free_irq;
+
+	dac->req.req.channel = ret;
+	dac->req.req.block_complete = at32dac_dma_block_complete;
+	dac->req.req.error = at32dac_dma_error;
+	dac->req.data_reg = regs->start + DAC_DATA;
+	dac->req.periph_id = 2; /* FIXME */
+	dac->req.direction = DMA_DIR_MEM_TO_PERIPH;
+	dac->req.width = DMA_WIDTH_32BIT;
+
+	/* Make sure the DAC is silent and disabled */
+	dac_writel(dac, DATA, 0);
+	dac_writel(dac, CTRL, 0);
+
+	ret = register_sound_dsp(&at32dac_dsp_fops, -1);
+	if (ret < 0)
+		goto out_free_dma;
+	dac->dev_dsp = ret;
+
+	/* TODO: Register mixer */
+
+	the_dac = dac;
+	platform_set_drvdata(pdev, dac);
+
+	return 0;
+
+out_free_dma:
+	dma_release_channel(dac->req.req.dmac, dac->req.req.channel);
+out_free_irq:
+	free_irq(irq, dac);
+out_unmap_regs:
+	iounmap(dac->regs);
+out_free_dac:
+	kfree(dac);
+out_disable_clk:
+	clk_disable(mck);
+	clk_put(mck);
+	return ret;
+}
+
+static int __devexit at32dac_remove(struct platform_device *pdev)
+{
+	struct at32_dac *dac;
+
+	dac = platform_get_drvdata(pdev);
+	if (dac) {
+		unregister_sound_dsp(dac->dev_dsp);
+		dma_release_channel(dac->req.req.dmac, dac->req.req.channel);
+		free_irq(platform_get_irq(pdev, 0), dac);
+		iounmap(dac->regs);
+		clk_disable(dac->mck);
+		clk_put(dac->mck);
+		kfree(dac);
+		platform_set_drvdata(pdev, NULL);
+		the_dac = NULL;
+	}
+
+	return 0;
+}
+
+static struct platform_driver at32dac_driver = {
+	.probe		= at32dac_probe,
+	.remove		= __devexit_p(at32dac_remove),
+	.driver		= {
+		.name	= "dac",
+	},
+};
+
+static int __init at32dac_init(void)
+{
+	return platform_driver_register(&at32dac_driver);
+}
+module_init(at32dac_init);
+
+static void __exit at32dac_exit(void)
+{
+	platform_driver_unregister(&at32dac_driver);
+}
+module_exit(at32dac_exit);
+
+MODULE_AUTHOR("Haavard Skinnemoen <hskinnemoen@atmel.com>");
+MODULE_DESCRIPTION("DMA Sound Driver for the Atmel AT32 on-chip DAC");
+MODULE_LICENSE("GPL");
Index: linux-2.6.18-avr32/sound/oss/at32dac.h
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.18-avr32/sound/oss/at32dac.h	2006-11-02 15:57:01.000000000 +0100
@@ -0,0 +1,65 @@
+/*
+ * Register definitions for the Atmel AT32 on-chip DAC.
+ *
+ * Copyright (C) 2006 Atmel Corporation
+ *
+ * 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.
+ */
+#ifndef __ASM_AVR32_DAC_H__
+#define __ASM_AVR32_DAC_H__
+
+/* DAC register offsets */
+#define DAC_DATA                                0x0000
+#define DAC_CTRL                                0x0008
+#define DAC_INT_MASK                            0x000c
+#define DAC_INT_EN                              0x0010
+#define DAC_INT_DIS                             0x0014
+#define DAC_INT_CLR                             0x0018
+#define DAC_INT_STATUS                          0x001c
+#define DAC_PDC_DATA                            0x0020
+
+/* Bitfields in DATA */
+#define DAC_DATA_OFFSET                         0
+#define DAC_DATA_SIZE                           32
+
+/* Bitfields in CTRL */
+#define DAC_SWAP_OFFSET                         30
+#define DAC_SWAP_SIZE                           1
+#define DAC_EN_OFFSET                           31
+#define DAC_EN_SIZE                             1
+
+/* Bitfields in INT_MASK */
+
+/* Bitfields in INT_EN */
+
+/* Bitfields in INT_DIS */
+#define DAC_TX_READY_OFFSET                     29
+#define DAC_TX_READY_SIZE                       1
+#define DAC_TX_BUFFER_EMPTY_OFFSET              30
+#define DAC_TX_BUFFER_EMPTY_SIZE                1
+#define DAC_CHANNEL_TX_END_OFFSET               31
+#define DAC_CHANNEL_TX_END_SIZE                 1
+
+/* Bitfields in INT_CLR */
+#define DAC_UNDERRUN_OFFSET                     28
+#define DAC_UNDERRUN_SIZE                       1
+
+/* Bitfields in INT_STATUS */
+
+/* Bitfields in PDC_DATA */
+
+/* Bit manipulation macros */
+#define DAC_BIT(name)                           (1 << DAC_##name##_OFFSET)
+#define DAC_BF(name,value)                      (((value) & ((1 << DAC_##name##_SIZE) - 1)) << DAC_##name##_OFFSET)
+#define DAC_BFEXT(name,value)                   (((value) >> DAC_##name##_OFFSET) & ((1 << DAC_##name##_SIZE) - 1))
+#define DAC_BFINS(name,value,old)               (((old) & ~(((1 << DAC_##name##_SIZE) - 1) << DAC_##name##_OFFSET)) | DAC_BF(name,value))
+
+/* Register access macros */
+#define dac_readl(port,reg)				\
+	__raw_readl((port)->regs + DAC_##reg)
+#define dac_writel(port,reg,value)			\
+	__raw_writel((value), (port)->regs + DAC_##reg)
+
+#endif /* __ASM_AVR32_DAC_H__ */