[Feature]add MT2731_MP2_MR2_SVN388 baseline version

Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/drivers/dma/dma-jz4740.c b/src/kernel/linux/v4.14/drivers/dma/dma-jz4740.c
new file mode 100644
index 0000000..afd5e10
--- /dev/null
+++ b/src/kernel/linux/v4.14/drivers/dma/dma-jz4740.c
@@ -0,0 +1,613 @@
+/*
+ *  Copyright (C) 2013, Lars-Peter Clausen <lars@metafoo.de>
+ *  JZ4740 DMAC support
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under  the terms of the GNU General	 Public License as published by the
+ *  Free Software Foundation;  either version 2 of the License, or (at your
+ *  option) any later version.
+ *
+ */
+
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/irq.h>
+#include <linux/clk.h>
+
+#include "virt-dma.h"
+
+#define JZ_DMA_NR_CHANS 6
+
+#define JZ_REG_DMA_SRC_ADDR(x)		(0x00 + (x) * 0x20)
+#define JZ_REG_DMA_DST_ADDR(x)		(0x04 + (x) * 0x20)
+#define JZ_REG_DMA_TRANSFER_COUNT(x)	(0x08 + (x) * 0x20)
+#define JZ_REG_DMA_REQ_TYPE(x)		(0x0C + (x) * 0x20)
+#define JZ_REG_DMA_STATUS_CTRL(x)	(0x10 + (x) * 0x20)
+#define JZ_REG_DMA_CMD(x)		(0x14 + (x) * 0x20)
+#define JZ_REG_DMA_DESC_ADDR(x)		(0x18 + (x) * 0x20)
+
+#define JZ_REG_DMA_CTRL			0x300
+#define JZ_REG_DMA_IRQ			0x304
+#define JZ_REG_DMA_DOORBELL		0x308
+#define JZ_REG_DMA_DOORBELL_SET		0x30C
+
+#define JZ_DMA_STATUS_CTRL_NO_DESC		BIT(31)
+#define JZ_DMA_STATUS_CTRL_DESC_INV		BIT(6)
+#define JZ_DMA_STATUS_CTRL_ADDR_ERR		BIT(4)
+#define JZ_DMA_STATUS_CTRL_TRANSFER_DONE	BIT(3)
+#define JZ_DMA_STATUS_CTRL_HALT			BIT(2)
+#define JZ_DMA_STATUS_CTRL_COUNT_TERMINATE	BIT(1)
+#define JZ_DMA_STATUS_CTRL_ENABLE		BIT(0)
+
+#define JZ_DMA_CMD_SRC_INC			BIT(23)
+#define JZ_DMA_CMD_DST_INC			BIT(22)
+#define JZ_DMA_CMD_RDIL_MASK			(0xf << 16)
+#define JZ_DMA_CMD_SRC_WIDTH_MASK		(0x3 << 14)
+#define JZ_DMA_CMD_DST_WIDTH_MASK		(0x3 << 12)
+#define JZ_DMA_CMD_INTERVAL_LENGTH_MASK		(0x7 << 8)
+#define JZ_DMA_CMD_BLOCK_MODE			BIT(7)
+#define JZ_DMA_CMD_DESC_VALID			BIT(4)
+#define JZ_DMA_CMD_DESC_VALID_MODE		BIT(3)
+#define JZ_DMA_CMD_VALID_IRQ_ENABLE		BIT(2)
+#define JZ_DMA_CMD_TRANSFER_IRQ_ENABLE		BIT(1)
+#define JZ_DMA_CMD_LINK_ENABLE			BIT(0)
+
+#define JZ_DMA_CMD_FLAGS_OFFSET 22
+#define JZ_DMA_CMD_RDIL_OFFSET 16
+#define JZ_DMA_CMD_SRC_WIDTH_OFFSET 14
+#define JZ_DMA_CMD_DST_WIDTH_OFFSET 12
+#define JZ_DMA_CMD_TRANSFER_SIZE_OFFSET 8
+#define JZ_DMA_CMD_MODE_OFFSET 7
+
+#define JZ_DMA_CTRL_PRIORITY_MASK		(0x3 << 8)
+#define JZ_DMA_CTRL_HALT			BIT(3)
+#define JZ_DMA_CTRL_ADDRESS_ERROR		BIT(2)
+#define JZ_DMA_CTRL_ENABLE			BIT(0)
+
+enum jz4740_dma_width {
+	JZ4740_DMA_WIDTH_32BIT	= 0,
+	JZ4740_DMA_WIDTH_8BIT	= 1,
+	JZ4740_DMA_WIDTH_16BIT	= 2,
+};
+
+enum jz4740_dma_transfer_size {
+	JZ4740_DMA_TRANSFER_SIZE_4BYTE	= 0,
+	JZ4740_DMA_TRANSFER_SIZE_1BYTE	= 1,
+	JZ4740_DMA_TRANSFER_SIZE_2BYTE	= 2,
+	JZ4740_DMA_TRANSFER_SIZE_16BYTE = 3,
+	JZ4740_DMA_TRANSFER_SIZE_32BYTE = 4,
+};
+
+enum jz4740_dma_flags {
+	JZ4740_DMA_SRC_AUTOINC = 0x2,
+	JZ4740_DMA_DST_AUTOINC = 0x1,
+};
+
+enum jz4740_dma_mode {
+	JZ4740_DMA_MODE_SINGLE	= 0,
+	JZ4740_DMA_MODE_BLOCK	= 1,
+};
+
+struct jz4740_dma_sg {
+	dma_addr_t addr;
+	unsigned int len;
+};
+
+struct jz4740_dma_desc {
+	struct virt_dma_desc vdesc;
+
+	enum dma_transfer_direction direction;
+	bool cyclic;
+
+	unsigned int num_sgs;
+	struct jz4740_dma_sg sg[];
+};
+
+struct jz4740_dmaengine_chan {
+	struct virt_dma_chan vchan;
+	unsigned int id;
+
+	dma_addr_t fifo_addr;
+	unsigned int transfer_shift;
+
+	struct jz4740_dma_desc *desc;
+	unsigned int next_sg;
+};
+
+struct jz4740_dma_dev {
+	struct dma_device ddev;
+	void __iomem *base;
+	struct clk *clk;
+
+	struct jz4740_dmaengine_chan chan[JZ_DMA_NR_CHANS];
+};
+
+static struct jz4740_dma_dev *jz4740_dma_chan_get_dev(
+	struct jz4740_dmaengine_chan *chan)
+{
+	return container_of(chan->vchan.chan.device, struct jz4740_dma_dev,
+		ddev);
+}
+
+static struct jz4740_dmaengine_chan *to_jz4740_dma_chan(struct dma_chan *c)
+{
+	return container_of(c, struct jz4740_dmaengine_chan, vchan.chan);
+}
+
+static struct jz4740_dma_desc *to_jz4740_dma_desc(struct virt_dma_desc *vdesc)
+{
+	return container_of(vdesc, struct jz4740_dma_desc, vdesc);
+}
+
+static inline uint32_t jz4740_dma_read(struct jz4740_dma_dev *dmadev,
+	unsigned int reg)
+{
+	return readl(dmadev->base + reg);
+}
+
+static inline void jz4740_dma_write(struct jz4740_dma_dev *dmadev,
+	unsigned reg, uint32_t val)
+{
+	writel(val, dmadev->base + reg);
+}
+
+static inline void jz4740_dma_write_mask(struct jz4740_dma_dev *dmadev,
+	unsigned int reg, uint32_t val, uint32_t mask)
+{
+	uint32_t tmp;
+
+	tmp = jz4740_dma_read(dmadev, reg);
+	tmp &= ~mask;
+	tmp |= val;
+	jz4740_dma_write(dmadev, reg, tmp);
+}
+
+static struct jz4740_dma_desc *jz4740_dma_alloc_desc(unsigned int num_sgs)
+{
+	return kzalloc(sizeof(struct jz4740_dma_desc) +
+		sizeof(struct jz4740_dma_sg) * num_sgs, GFP_ATOMIC);
+}
+
+static enum jz4740_dma_width jz4740_dma_width(enum dma_slave_buswidth width)
+{
+	switch (width) {
+	case DMA_SLAVE_BUSWIDTH_1_BYTE:
+		return JZ4740_DMA_WIDTH_8BIT;
+	case DMA_SLAVE_BUSWIDTH_2_BYTES:
+		return JZ4740_DMA_WIDTH_16BIT;
+	case DMA_SLAVE_BUSWIDTH_4_BYTES:
+		return JZ4740_DMA_WIDTH_32BIT;
+	default:
+		return JZ4740_DMA_WIDTH_32BIT;
+	}
+}
+
+static enum jz4740_dma_transfer_size jz4740_dma_maxburst(u32 maxburst)
+{
+	if (maxburst <= 1)
+		return JZ4740_DMA_TRANSFER_SIZE_1BYTE;
+	else if (maxburst <= 3)
+		return JZ4740_DMA_TRANSFER_SIZE_2BYTE;
+	else if (maxburst <= 15)
+		return JZ4740_DMA_TRANSFER_SIZE_4BYTE;
+	else if (maxburst <= 31)
+		return JZ4740_DMA_TRANSFER_SIZE_16BYTE;
+
+	return JZ4740_DMA_TRANSFER_SIZE_32BYTE;
+}
+
+static int jz4740_dma_slave_config(struct dma_chan *c,
+				   struct dma_slave_config *config)
+{
+	struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
+	struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
+	enum jz4740_dma_width src_width;
+	enum jz4740_dma_width dst_width;
+	enum jz4740_dma_transfer_size transfer_size;
+	enum jz4740_dma_flags flags;
+	uint32_t cmd;
+
+	switch (config->direction) {
+	case DMA_MEM_TO_DEV:
+		flags = JZ4740_DMA_SRC_AUTOINC;
+		transfer_size = jz4740_dma_maxburst(config->dst_maxburst);
+		chan->fifo_addr = config->dst_addr;
+		break;
+	case DMA_DEV_TO_MEM:
+		flags = JZ4740_DMA_DST_AUTOINC;
+		transfer_size = jz4740_dma_maxburst(config->src_maxburst);
+		chan->fifo_addr = config->src_addr;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	src_width = jz4740_dma_width(config->src_addr_width);
+	dst_width = jz4740_dma_width(config->dst_addr_width);
+
+	switch (transfer_size) {
+	case JZ4740_DMA_TRANSFER_SIZE_2BYTE:
+		chan->transfer_shift = 1;
+		break;
+	case JZ4740_DMA_TRANSFER_SIZE_4BYTE:
+		chan->transfer_shift = 2;
+		break;
+	case JZ4740_DMA_TRANSFER_SIZE_16BYTE:
+		chan->transfer_shift = 4;
+		break;
+	case JZ4740_DMA_TRANSFER_SIZE_32BYTE:
+		chan->transfer_shift = 5;
+		break;
+	default:
+		chan->transfer_shift = 0;
+		break;
+	}
+
+	cmd = flags << JZ_DMA_CMD_FLAGS_OFFSET;
+	cmd |= src_width << JZ_DMA_CMD_SRC_WIDTH_OFFSET;
+	cmd |= dst_width << JZ_DMA_CMD_DST_WIDTH_OFFSET;
+	cmd |= transfer_size << JZ_DMA_CMD_TRANSFER_SIZE_OFFSET;
+	cmd |= JZ4740_DMA_MODE_SINGLE << JZ_DMA_CMD_MODE_OFFSET;
+	cmd |= JZ_DMA_CMD_TRANSFER_IRQ_ENABLE;
+
+	jz4740_dma_write(dmadev, JZ_REG_DMA_CMD(chan->id), cmd);
+	jz4740_dma_write(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0);
+	jz4740_dma_write(dmadev, JZ_REG_DMA_REQ_TYPE(chan->id),
+		config->slave_id);
+
+	return 0;
+}
+
+static int jz4740_dma_terminate_all(struct dma_chan *c)
+{
+	struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
+	struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
+	unsigned long flags;
+	LIST_HEAD(head);
+
+	spin_lock_irqsave(&chan->vchan.lock, flags);
+	jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0,
+			JZ_DMA_STATUS_CTRL_ENABLE);
+	chan->desc = NULL;
+	vchan_get_all_descriptors(&chan->vchan, &head);
+	spin_unlock_irqrestore(&chan->vchan.lock, flags);
+
+	vchan_dma_desc_free_list(&chan->vchan, &head);
+
+	return 0;
+}
+
+static int jz4740_dma_start_transfer(struct jz4740_dmaengine_chan *chan)
+{
+	struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
+	dma_addr_t src_addr, dst_addr;
+	struct virt_dma_desc *vdesc;
+	struct jz4740_dma_sg *sg;
+
+	jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id), 0,
+			JZ_DMA_STATUS_CTRL_ENABLE);
+
+	if (!chan->desc) {
+		vdesc = vchan_next_desc(&chan->vchan);
+		if (!vdesc)
+			return 0;
+		chan->desc = to_jz4740_dma_desc(vdesc);
+		chan->next_sg = 0;
+	}
+
+	if (chan->next_sg == chan->desc->num_sgs)
+		chan->next_sg = 0;
+
+	sg = &chan->desc->sg[chan->next_sg];
+
+	if (chan->desc->direction == DMA_MEM_TO_DEV) {
+		src_addr = sg->addr;
+		dst_addr = chan->fifo_addr;
+	} else {
+		src_addr = chan->fifo_addr;
+		dst_addr = sg->addr;
+	}
+	jz4740_dma_write(dmadev, JZ_REG_DMA_SRC_ADDR(chan->id), src_addr);
+	jz4740_dma_write(dmadev, JZ_REG_DMA_DST_ADDR(chan->id), dst_addr);
+	jz4740_dma_write(dmadev, JZ_REG_DMA_TRANSFER_COUNT(chan->id),
+			sg->len >> chan->transfer_shift);
+
+	chan->next_sg++;
+
+	jz4740_dma_write_mask(dmadev, JZ_REG_DMA_STATUS_CTRL(chan->id),
+			JZ_DMA_STATUS_CTRL_NO_DESC | JZ_DMA_STATUS_CTRL_ENABLE,
+			JZ_DMA_STATUS_CTRL_HALT | JZ_DMA_STATUS_CTRL_NO_DESC |
+			JZ_DMA_STATUS_CTRL_ENABLE);
+
+	jz4740_dma_write_mask(dmadev, JZ_REG_DMA_CTRL,
+			JZ_DMA_CTRL_ENABLE,
+			JZ_DMA_CTRL_HALT | JZ_DMA_CTRL_ENABLE);
+
+	return 0;
+}
+
+static void jz4740_dma_chan_irq(struct jz4740_dmaengine_chan *chan)
+{
+	spin_lock(&chan->vchan.lock);
+	if (chan->desc) {
+		if (chan->desc->cyclic) {
+			vchan_cyclic_callback(&chan->desc->vdesc);
+		} else {
+			if (chan->next_sg == chan->desc->num_sgs) {
+				list_del(&chan->desc->vdesc.node);
+				vchan_cookie_complete(&chan->desc->vdesc);
+				chan->desc = NULL;
+			}
+		}
+	}
+	jz4740_dma_start_transfer(chan);
+	spin_unlock(&chan->vchan.lock);
+}
+
+static irqreturn_t jz4740_dma_irq(int irq, void *devid)
+{
+	struct jz4740_dma_dev *dmadev = devid;
+	uint32_t irq_status;
+	unsigned int i;
+
+	irq_status = readl(dmadev->base + JZ_REG_DMA_IRQ);
+
+	for (i = 0; i < 6; ++i) {
+		if (irq_status & (1 << i)) {
+			jz4740_dma_write_mask(dmadev,
+				JZ_REG_DMA_STATUS_CTRL(i), 0,
+				JZ_DMA_STATUS_CTRL_ENABLE |
+				JZ_DMA_STATUS_CTRL_TRANSFER_DONE);
+
+			jz4740_dma_chan_irq(&dmadev->chan[i]);
+		}
+	}
+
+	return IRQ_HANDLED;
+}
+
+static void jz4740_dma_issue_pending(struct dma_chan *c)
+{
+	struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
+	unsigned long flags;
+
+	spin_lock_irqsave(&chan->vchan.lock, flags);
+	if (vchan_issue_pending(&chan->vchan) && !chan->desc)
+		jz4740_dma_start_transfer(chan);
+	spin_unlock_irqrestore(&chan->vchan.lock, flags);
+}
+
+static struct dma_async_tx_descriptor *jz4740_dma_prep_slave_sg(
+	struct dma_chan *c, struct scatterlist *sgl,
+	unsigned int sg_len, enum dma_transfer_direction direction,
+	unsigned long flags, void *context)
+{
+	struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
+	struct jz4740_dma_desc *desc;
+	struct scatterlist *sg;
+	unsigned int i;
+
+	desc = jz4740_dma_alloc_desc(sg_len);
+	if (!desc)
+		return NULL;
+
+	for_each_sg(sgl, sg, sg_len, i) {
+		desc->sg[i].addr = sg_dma_address(sg);
+		desc->sg[i].len = sg_dma_len(sg);
+	}
+
+	desc->num_sgs = sg_len;
+	desc->direction = direction;
+	desc->cyclic = false;
+
+	return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
+}
+
+static struct dma_async_tx_descriptor *jz4740_dma_prep_dma_cyclic(
+	struct dma_chan *c, dma_addr_t buf_addr, size_t buf_len,
+	size_t period_len, enum dma_transfer_direction direction,
+	unsigned long flags)
+{
+	struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
+	struct jz4740_dma_desc *desc;
+	unsigned int num_periods, i;
+
+	if (buf_len % period_len)
+		return NULL;
+
+	num_periods = buf_len / period_len;
+
+	desc = jz4740_dma_alloc_desc(num_periods);
+	if (!desc)
+		return NULL;
+
+	for (i = 0; i < num_periods; i++) {
+		desc->sg[i].addr = buf_addr;
+		desc->sg[i].len = period_len;
+		buf_addr += period_len;
+	}
+
+	desc->num_sgs = num_periods;
+	desc->direction = direction;
+	desc->cyclic = true;
+
+	return vchan_tx_prep(&chan->vchan, &desc->vdesc, flags);
+}
+
+static size_t jz4740_dma_desc_residue(struct jz4740_dmaengine_chan *chan,
+	struct jz4740_dma_desc *desc, unsigned int next_sg)
+{
+	struct jz4740_dma_dev *dmadev = jz4740_dma_chan_get_dev(chan);
+	unsigned int residue, count;
+	unsigned int i;
+
+	residue = 0;
+
+	for (i = next_sg; i < desc->num_sgs; i++)
+		residue += desc->sg[i].len;
+
+	if (next_sg != 0) {
+		count = jz4740_dma_read(dmadev,
+			JZ_REG_DMA_TRANSFER_COUNT(chan->id));
+		residue += count << chan->transfer_shift;
+	}
+
+	return residue;
+}
+
+static enum dma_status jz4740_dma_tx_status(struct dma_chan *c,
+	dma_cookie_t cookie, struct dma_tx_state *state)
+{
+	struct jz4740_dmaengine_chan *chan = to_jz4740_dma_chan(c);
+	struct virt_dma_desc *vdesc;
+	enum dma_status status;
+	unsigned long flags;
+
+	status = dma_cookie_status(c, cookie, state);
+	if (status == DMA_COMPLETE || !state)
+		return status;
+
+	spin_lock_irqsave(&chan->vchan.lock, flags);
+	vdesc = vchan_find_desc(&chan->vchan, cookie);
+	if (cookie == chan->desc->vdesc.tx.cookie) {
+		state->residue = jz4740_dma_desc_residue(chan, chan->desc,
+				chan->next_sg);
+	} else if (vdesc) {
+		state->residue = jz4740_dma_desc_residue(chan,
+				to_jz4740_dma_desc(vdesc), 0);
+	} else {
+		state->residue = 0;
+	}
+	spin_unlock_irqrestore(&chan->vchan.lock, flags);
+
+	return status;
+}
+
+static void jz4740_dma_free_chan_resources(struct dma_chan *c)
+{
+	vchan_free_chan_resources(to_virt_chan(c));
+}
+
+static void jz4740_dma_desc_free(struct virt_dma_desc *vdesc)
+{
+	kfree(container_of(vdesc, struct jz4740_dma_desc, vdesc));
+}
+
+#define JZ4740_DMA_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
+	BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | BIT(DMA_SLAVE_BUSWIDTH_4_BYTES))
+
+static int jz4740_dma_probe(struct platform_device *pdev)
+{
+	struct jz4740_dmaengine_chan *chan;
+	struct jz4740_dma_dev *dmadev;
+	struct dma_device *dd;
+	unsigned int i;
+	struct resource *res;
+	int ret;
+	int irq;
+
+	dmadev = devm_kzalloc(&pdev->dev, sizeof(*dmadev), GFP_KERNEL);
+	if (!dmadev)
+		return -EINVAL;
+
+	dd = &dmadev->ddev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	dmadev->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(dmadev->base))
+		return PTR_ERR(dmadev->base);
+
+	dmadev->clk = clk_get(&pdev->dev, "dma");
+	if (IS_ERR(dmadev->clk))
+		return PTR_ERR(dmadev->clk);
+
+	clk_prepare_enable(dmadev->clk);
+
+	dma_cap_set(DMA_SLAVE, dd->cap_mask);
+	dma_cap_set(DMA_CYCLIC, dd->cap_mask);
+	dd->device_free_chan_resources = jz4740_dma_free_chan_resources;
+	dd->device_tx_status = jz4740_dma_tx_status;
+	dd->device_issue_pending = jz4740_dma_issue_pending;
+	dd->device_prep_slave_sg = jz4740_dma_prep_slave_sg;
+	dd->device_prep_dma_cyclic = jz4740_dma_prep_dma_cyclic;
+	dd->device_config = jz4740_dma_slave_config;
+	dd->device_terminate_all = jz4740_dma_terminate_all;
+	dd->src_addr_widths = JZ4740_DMA_BUSWIDTHS;
+	dd->dst_addr_widths = JZ4740_DMA_BUSWIDTHS;
+	dd->directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV);
+	dd->residue_granularity = DMA_RESIDUE_GRANULARITY_BURST;
+	dd->dev = &pdev->dev;
+	INIT_LIST_HEAD(&dd->channels);
+
+	for (i = 0; i < JZ_DMA_NR_CHANS; i++) {
+		chan = &dmadev->chan[i];
+		chan->id = i;
+		chan->vchan.desc_free = jz4740_dma_desc_free;
+		vchan_init(&chan->vchan, dd);
+	}
+
+	ret = dma_async_device_register(dd);
+	if (ret)
+		goto err_clk;
+
+	irq = platform_get_irq(pdev, 0);
+	ret = request_irq(irq, jz4740_dma_irq, 0, dev_name(&pdev->dev), dmadev);
+	if (ret)
+		goto err_unregister;
+
+	platform_set_drvdata(pdev, dmadev);
+
+	return 0;
+
+err_unregister:
+	dma_async_device_unregister(dd);
+err_clk:
+	clk_disable_unprepare(dmadev->clk);
+	return ret;
+}
+
+static void jz4740_cleanup_vchan(struct dma_device *dmadev)
+{
+	struct jz4740_dmaengine_chan *chan, *_chan;
+
+	list_for_each_entry_safe(chan, _chan,
+				&dmadev->channels, vchan.chan.device_node) {
+		list_del(&chan->vchan.chan.device_node);
+		tasklet_kill(&chan->vchan.task);
+	}
+}
+
+
+static int jz4740_dma_remove(struct platform_device *pdev)
+{
+	struct jz4740_dma_dev *dmadev = platform_get_drvdata(pdev);
+	int irq = platform_get_irq(pdev, 0);
+
+	free_irq(irq, dmadev);
+
+	jz4740_cleanup_vchan(&dmadev->ddev);
+	dma_async_device_unregister(&dmadev->ddev);
+	clk_disable_unprepare(dmadev->clk);
+
+	return 0;
+}
+
+static struct platform_driver jz4740_dma_driver = {
+	.probe = jz4740_dma_probe,
+	.remove = jz4740_dma_remove,
+	.driver = {
+		.name = "jz4740-dma",
+	},
+};
+module_platform_driver(jz4740_dma_driver);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("JZ4740 DMA driver");
+MODULE_LICENSE("GPL v2");