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From:   Arnd Bergmann <arnd@kernel.org>
To:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        dmaengine@vger.kernel.org, Vinod Koul <vkoul@kernel.org>
Cc:     Arnd Bergmann <arnd@arndb.de>, Jun Nie <jun.nie@linaro.org>,
        Shawn Guo <shawnguo@kernel.org>
Subject: [PATCH 2/3] dmaengine: remove zte zx driver
Date:   Wed, 20 Jan 2021 14:18:58 +0100
Message-Id: <20210120131859.2056308-3-arnd@kernel.org>
In-Reply-To: <20210120131859.2056308-1-arnd@kernel.org>
References: <20210120131859.2056308-1-arnd@kernel.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Arnd Bergmann <arnd@arndb.de>

The zte zx platform is getting removed, so this driver is no
longer needed.

Cc: Jun Nie <jun.nie@linaro.org>
Cc: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 .../devicetree/bindings/dma/zxdma.txt         |  38 -
 drivers/dma/Kconfig                           |   9 -
 drivers/dma/Makefile                          |   1 -
 drivers/dma/zx_dma.c                          | 941 ------------------
 4 files changed, 989 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/dma/zxdma.txt
 delete mode 100644 drivers/dma/zx_dma.c

diff --git a/Documentation/devicetree/bindings/dma/zxdma.txt b/Documentation/devicetree/bindings/dma/zxdma.txt
deleted file mode 100644
index 0ab80f69e566..000000000000
--- a/Documentation/devicetree/bindings/dma/zxdma.txt
+++ /dev/null
@@ -1,38 +0,0 @@
-* ZTE ZX296702 DMA controller
-
-Required properties:
-- compatible: Should be "zte,zx296702-dma"
-- reg: Should contain DMA registers location and length.
-- interrupts: Should contain one interrupt shared by all channel
-- #dma-cells: see dma.txt, should be 1, para number
-- dma-channels: physical channels supported
-- dma-requests: virtual channels supported, each virtual channel
-		have specific request line
-- clocks: clock required
-
-Example:
-
-Controller:
-	dma: dma-controller@09c00000{
-		compatible = "zte,zx296702-dma";
-		reg = <0x09c00000 0x1000>;
-		clocks = <&topclk ZX296702_DMA_ACLK>;
-		interrupts = <GIC_SPI 66 IRQ_TYPE_LEVEL_HIGH>;
-		#dma-cells = <1>;
-		dma-channels = <24>;
-		dma-requests = <24>;
-	};
-
-Client:
-Use specific request line passing from dmax
-For example, spdif0 tx channel request line is 4
-	spdif0: spdif0@b004000 {
-		#sound-dai-cells = <0>;
-		compatible = "zte,zx296702-spdif";
-		reg = <0x0b004000 0x1000>;
-		clocks = <&lsp0clk ZX296702_SPDIF0_DIV>;
-		clock-names = "tx";
-		interrupts = <GIC_SPI 21 IRQ_TYPE_LEVEL_HIGH>;
-		dmas = <&dma 4>;
-		dma-names = "tx";
-	}
diff --git a/drivers/dma/Kconfig b/drivers/dma/Kconfig
index 1935cf39f753..36a49cc143d2 100644
--- a/drivers/dma/Kconfig
+++ b/drivers/dma/Kconfig
@@ -703,15 +703,6 @@ config XILINX_ZYNQMP_DPDMA
 	  driver provides the dmaengine required by the DisplayPort subsystem
 	  display driver.
 
-config ZX_DMA
-	tristate "ZTE ZX DMA support"
-	depends on ARCH_ZX || COMPILE_TEST
-	select DMA_ENGINE
-	select DMA_VIRTUAL_CHANNELS
-	help
-	  Support the DMA engine for ZTE ZX family platform devices.
-
-
 # driver files
 source "drivers/dma/bestcomm/Kconfig"
 
diff --git a/drivers/dma/Makefile b/drivers/dma/Makefile
index 93327554560e..9713d382ba55 100644
--- a/drivers/dma/Makefile
+++ b/drivers/dma/Makefile
@@ -78,7 +78,6 @@ obj-$(CONFIG_TIMB_DMA) += timb_dma.o
 obj-$(CONFIG_UNIPHIER_MDMAC) += uniphier-mdmac.o
 obj-$(CONFIG_UNIPHIER_XDMAC) += uniphier-xdmac.o
 obj-$(CONFIG_XGENE_DMA) += xgene-dma.o
-obj-$(CONFIG_ZX_DMA) += zx_dma.o
 obj-$(CONFIG_ST_FDMA) += st_fdma.o
 obj-$(CONFIG_FSL_DPAA2_QDMA) += fsl-dpaa2-qdma/
 
diff --git a/drivers/dma/zx_dma.c b/drivers/dma/zx_dma.c
deleted file mode 100644
index b057582b2fac..000000000000
--- a/drivers/dma/zx_dma.c
+++ /dev/null
@@ -1,941 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * Copyright 2015 Linaro.
- */
-#include <linux/sched.h>
-#include <linux/device.h>
-#include <linux/dmaengine.h>
-#include <linux/dma-mapping.h>
-#include <linux/dmapool.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/slab.h>
-#include <linux/spinlock.h>
-#include <linux/of_device.h>
-#include <linux/of.h>
-#include <linux/clk.h>
-#include <linux/of_dma.h>
-
-#include "virt-dma.h"
-
-#define DRIVER_NAME		"zx-dma"
-#define DMA_ALIGN		4
-#define DMA_MAX_SIZE		(0x10000 - 512)
-#define LLI_BLOCK_SIZE		(4 * PAGE_SIZE)
-
-#define REG_ZX_SRC_ADDR			0x00
-#define REG_ZX_DST_ADDR			0x04
-#define REG_ZX_TX_X_COUNT		0x08
-#define REG_ZX_TX_ZY_COUNT		0x0c
-#define REG_ZX_SRC_ZY_STEP		0x10
-#define REG_ZX_DST_ZY_STEP		0x14
-#define REG_ZX_LLI_ADDR			0x1c
-#define REG_ZX_CTRL			0x20
-#define REG_ZX_TC_IRQ			0x800
-#define REG_ZX_SRC_ERR_IRQ		0x804
-#define REG_ZX_DST_ERR_IRQ		0x808
-#define REG_ZX_CFG_ERR_IRQ		0x80c
-#define REG_ZX_TC_IRQ_RAW		0x810
-#define REG_ZX_SRC_ERR_IRQ_RAW		0x814
-#define REG_ZX_DST_ERR_IRQ_RAW		0x818
-#define REG_ZX_CFG_ERR_IRQ_RAW		0x81c
-#define REG_ZX_STATUS			0x820
-#define REG_ZX_DMA_GRP_PRIO		0x824
-#define REG_ZX_DMA_ARB			0x828
-
-#define ZX_FORCE_CLOSE			BIT(31)
-#define ZX_DST_BURST_WIDTH(x)		(((x) & 0x7) << 13)
-#define ZX_MAX_BURST_LEN		16
-#define ZX_SRC_BURST_LEN(x)		(((x) & 0xf) << 9)
-#define ZX_SRC_BURST_WIDTH(x)		(((x) & 0x7) << 6)
-#define ZX_IRQ_ENABLE_ALL		(3 << 4)
-#define ZX_DST_FIFO_MODE		BIT(3)
-#define ZX_SRC_FIFO_MODE		BIT(2)
-#define ZX_SOFT_REQ			BIT(1)
-#define ZX_CH_ENABLE			BIT(0)
-
-#define ZX_DMA_BUSWIDTHS \
-	(BIT(DMA_SLAVE_BUSWIDTH_UNDEFINED) | \
-	BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
-	BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
-	BIT(DMA_SLAVE_BUSWIDTH_4_BYTES) | \
-	BIT(DMA_SLAVE_BUSWIDTH_8_BYTES))
-
-enum zx_dma_burst_width {
-	ZX_DMA_WIDTH_8BIT	= 0,
-	ZX_DMA_WIDTH_16BIT	= 1,
-	ZX_DMA_WIDTH_32BIT	= 2,
-	ZX_DMA_WIDTH_64BIT	= 3,
-};
-
-struct zx_desc_hw {
-	u32 saddr;
-	u32 daddr;
-	u32 src_x;
-	u32 src_zy;
-	u32 src_zy_step;
-	u32 dst_zy_step;
-	u32 reserved1;
-	u32 lli;
-	u32 ctr;
-	u32 reserved[7]; /* pack as hardware registers region size */
-} __aligned(32);
-
-struct zx_dma_desc_sw {
-	struct virt_dma_desc	vd;
-	dma_addr_t		desc_hw_lli;
-	size_t			desc_num;
-	size_t			size;
-	struct zx_desc_hw	*desc_hw;
-};
-
-struct zx_dma_phy;
-
-struct zx_dma_chan {
-	struct dma_slave_config slave_cfg;
-	int			id; /* Request phy chan id */
-	u32			ccfg;
-	u32			cyclic;
-	struct virt_dma_chan	vc;
-	struct zx_dma_phy	*phy;
-	struct list_head	node;
-	dma_addr_t		dev_addr;
-	enum dma_status		status;
-};
-
-struct zx_dma_phy {
-	u32			idx;
-	void __iomem		*base;
-	struct zx_dma_chan	*vchan;
-	struct zx_dma_desc_sw	*ds_run;
-	struct zx_dma_desc_sw	*ds_done;
-};
-
-struct zx_dma_dev {
-	struct dma_device	slave;
-	void __iomem		*base;
-	spinlock_t		lock; /* lock for ch and phy */
-	struct list_head	chan_pending;
-	struct zx_dma_phy	*phy;
-	struct zx_dma_chan	*chans;
-	struct clk		*clk;
-	struct dma_pool		*pool;
-	u32			dma_channels;
-	u32			dma_requests;
-	int 			irq;
-};
-
-#define to_zx_dma(dmadev) container_of(dmadev, struct zx_dma_dev, slave)
-
-static struct zx_dma_chan *to_zx_chan(struct dma_chan *chan)
-{
-	return container_of(chan, struct zx_dma_chan, vc.chan);
-}
-
-static void zx_dma_terminate_chan(struct zx_dma_phy *phy, struct zx_dma_dev *d)
-{
-	u32 val = 0;
-
-	val = readl_relaxed(phy->base + REG_ZX_CTRL);
-	val &= ~ZX_CH_ENABLE;
-	val |= ZX_FORCE_CLOSE;
-	writel_relaxed(val, phy->base + REG_ZX_CTRL);
-
-	val = 0x1 << phy->idx;
-	writel_relaxed(val, d->base + REG_ZX_TC_IRQ_RAW);
-	writel_relaxed(val, d->base + REG_ZX_SRC_ERR_IRQ_RAW);
-	writel_relaxed(val, d->base + REG_ZX_DST_ERR_IRQ_RAW);
-	writel_relaxed(val, d->base + REG_ZX_CFG_ERR_IRQ_RAW);
-}
-
-static void zx_dma_set_desc(struct zx_dma_phy *phy, struct zx_desc_hw *hw)
-{
-	writel_relaxed(hw->saddr, phy->base + REG_ZX_SRC_ADDR);
-	writel_relaxed(hw->daddr, phy->base + REG_ZX_DST_ADDR);
-	writel_relaxed(hw->src_x, phy->base + REG_ZX_TX_X_COUNT);
-	writel_relaxed(0, phy->base + REG_ZX_TX_ZY_COUNT);
-	writel_relaxed(0, phy->base + REG_ZX_SRC_ZY_STEP);
-	writel_relaxed(0, phy->base + REG_ZX_DST_ZY_STEP);
-	writel_relaxed(hw->lli, phy->base + REG_ZX_LLI_ADDR);
-	writel_relaxed(hw->ctr, phy->base + REG_ZX_CTRL);
-}
-
-static u32 zx_dma_get_curr_lli(struct zx_dma_phy *phy)
-{
-	return readl_relaxed(phy->base + REG_ZX_LLI_ADDR);
-}
-
-static u32 zx_dma_get_chan_stat(struct zx_dma_dev *d)
-{
-	return readl_relaxed(d->base + REG_ZX_STATUS);
-}
-
-static void zx_dma_init_state(struct zx_dma_dev *d)
-{
-	/* set same priority */
-	writel_relaxed(0x0, d->base + REG_ZX_DMA_ARB);
-	/* clear all irq */
-	writel_relaxed(0xffffffff, d->base + REG_ZX_TC_IRQ_RAW);
-	writel_relaxed(0xffffffff, d->base + REG_ZX_SRC_ERR_IRQ_RAW);
-	writel_relaxed(0xffffffff, d->base + REG_ZX_DST_ERR_IRQ_RAW);
-	writel_relaxed(0xffffffff, d->base + REG_ZX_CFG_ERR_IRQ_RAW);
-}
-
-static int zx_dma_start_txd(struct zx_dma_chan *c)
-{
-	struct zx_dma_dev *d = to_zx_dma(c->vc.chan.device);
-	struct virt_dma_desc *vd = vchan_next_desc(&c->vc);
-
-	if (!c->phy)
-		return -EAGAIN;
-
-	if (BIT(c->phy->idx) & zx_dma_get_chan_stat(d))
-		return -EAGAIN;
-
-	if (vd) {
-		struct zx_dma_desc_sw *ds =
-			container_of(vd, struct zx_dma_desc_sw, vd);
-		/*
-		 * fetch and remove request from vc->desc_issued
-		 * so vc->desc_issued only contains desc pending
-		 */
-		list_del(&ds->vd.node);
-		c->phy->ds_run = ds;
-		c->phy->ds_done = NULL;
-		/* start dma */
-		zx_dma_set_desc(c->phy, ds->desc_hw);
-		return 0;
-	}
-	c->phy->ds_done = NULL;
-	c->phy->ds_run = NULL;
-	return -EAGAIN;
-}
-
-static void zx_dma_task(struct zx_dma_dev *d)
-{
-	struct zx_dma_phy *p;
-	struct zx_dma_chan *c, *cn;
-	unsigned pch, pch_alloc = 0;
-	unsigned long flags;
-
-	/* check new dma request of running channel in vc->desc_issued */
-	list_for_each_entry_safe(c, cn, &d->slave.channels,
-				 vc.chan.device_node) {
-		spin_lock_irqsave(&c->vc.lock, flags);
-		p = c->phy;
-		if (p && p->ds_done && zx_dma_start_txd(c)) {
-			/* No current txd associated with this channel */
-			dev_dbg(d->slave.dev, "pchan %u: free\n", p->idx);
-			/* Mark this channel free */
-			c->phy = NULL;
-			p->vchan = NULL;
-		}
-		spin_unlock_irqrestore(&c->vc.lock, flags);
-	}
-
-	/* check new channel request in d->chan_pending */
-	spin_lock_irqsave(&d->lock, flags);
-	while (!list_empty(&d->chan_pending)) {
-		c = list_first_entry(&d->chan_pending,
-				     struct zx_dma_chan, node);
-		p = &d->phy[c->id];
-		if (!p->vchan) {
-			/* remove from d->chan_pending */
-			list_del_init(&c->node);
-			pch_alloc |= 1 << c->id;
-			/* Mark this channel allocated */
-			p->vchan = c;
-			c->phy = p;
-		} else {
-			dev_dbg(d->slave.dev, "pchan %u: busy!\n", c->id);
-		}
-	}
-	spin_unlock_irqrestore(&d->lock, flags);
-
-	for (pch = 0; pch < d->dma_channels; pch++) {
-		if (pch_alloc & (1 << pch)) {
-			p = &d->phy[pch];
-			c = p->vchan;
-			if (c) {
-				spin_lock_irqsave(&c->vc.lock, flags);
-				zx_dma_start_txd(c);
-				spin_unlock_irqrestore(&c->vc.lock, flags);
-			}
-		}
-	}
-}
-
-static irqreturn_t zx_dma_int_handler(int irq, void *dev_id)
-{
-	struct zx_dma_dev *d = (struct zx_dma_dev *)dev_id;
-	struct zx_dma_phy *p;
-	struct zx_dma_chan *c;
-	u32 tc = readl_relaxed(d->base + REG_ZX_TC_IRQ);
-	u32 serr = readl_relaxed(d->base + REG_ZX_SRC_ERR_IRQ);
-	u32 derr = readl_relaxed(d->base + REG_ZX_DST_ERR_IRQ);
-	u32 cfg = readl_relaxed(d->base + REG_ZX_CFG_ERR_IRQ);
-	u32 i, irq_chan = 0, task = 0;
-
-	while (tc) {
-		i = __ffs(tc);
-		tc &= ~BIT(i);
-		p = &d->phy[i];
-		c = p->vchan;
-		if (c) {
-			spin_lock(&c->vc.lock);
-			if (c->cyclic) {
-				vchan_cyclic_callback(&p->ds_run->vd);
-			} else {
-				vchan_cookie_complete(&p->ds_run->vd);
-				p->ds_done = p->ds_run;
-				task = 1;
-			}
-			spin_unlock(&c->vc.lock);
-			irq_chan |= BIT(i);
-		}
-	}
-
-	if (serr || derr || cfg)
-		dev_warn(d->slave.dev, "DMA ERR src 0x%x, dst 0x%x, cfg 0x%x\n",
-			 serr, derr, cfg);
-
-	writel_relaxed(irq_chan, d->base + REG_ZX_TC_IRQ_RAW);
-	writel_relaxed(serr, d->base + REG_ZX_SRC_ERR_IRQ_RAW);
-	writel_relaxed(derr, d->base + REG_ZX_DST_ERR_IRQ_RAW);
-	writel_relaxed(cfg, d->base + REG_ZX_CFG_ERR_IRQ_RAW);
-
-	if (task)
-		zx_dma_task(d);
-	return IRQ_HANDLED;
-}
-
-static void zx_dma_free_chan_resources(struct dma_chan *chan)
-{
-	struct zx_dma_chan *c = to_zx_chan(chan);
-	struct zx_dma_dev *d = to_zx_dma(chan->device);
-	unsigned long flags;
-
-	spin_lock_irqsave(&d->lock, flags);
-	list_del_init(&c->node);
-	spin_unlock_irqrestore(&d->lock, flags);
-
-	vchan_free_chan_resources(&c->vc);
-	c->ccfg = 0;
-}
-
-static enum dma_status zx_dma_tx_status(struct dma_chan *chan,
-					dma_cookie_t cookie,
-					struct dma_tx_state *state)
-{
-	struct zx_dma_chan *c = to_zx_chan(chan);
-	struct zx_dma_phy *p;
-	struct virt_dma_desc *vd;
-	unsigned long flags;
-	enum dma_status ret;
-	size_t bytes = 0;
-
-	ret = dma_cookie_status(&c->vc.chan, cookie, state);
-	if (ret == DMA_COMPLETE || !state)
-		return ret;
-
-	spin_lock_irqsave(&c->vc.lock, flags);
-	p = c->phy;
-	ret = c->status;
-
-	/*
-	 * If the cookie is on our issue queue, then the residue is
-	 * its total size.
-	 */
-	vd = vchan_find_desc(&c->vc, cookie);
-	if (vd) {
-		bytes = container_of(vd, struct zx_dma_desc_sw, vd)->size;
-	} else if ((!p) || (!p->ds_run)) {
-		bytes = 0;
-	} else {
-		struct zx_dma_desc_sw *ds = p->ds_run;
-		u32 clli = 0, index = 0;
-
-		bytes = 0;
-		clli = zx_dma_get_curr_lli(p);
-		index = (clli - ds->desc_hw_lli) /
-				sizeof(struct zx_desc_hw) + 1;
-		for (; index < ds->desc_num; index++) {
-			bytes += ds->desc_hw[index].src_x;
-			/* end of lli */
-			if (!ds->desc_hw[index].lli)
-				break;
-		}
-	}
-	spin_unlock_irqrestore(&c->vc.lock, flags);
-	dma_set_residue(state, bytes);
-	return ret;
-}
-
-static void zx_dma_issue_pending(struct dma_chan *chan)
-{
-	struct zx_dma_chan *c = to_zx_chan(chan);
-	struct zx_dma_dev *d = to_zx_dma(chan->device);
-	unsigned long flags;
-	int issue = 0;
-
-	spin_lock_irqsave(&c->vc.lock, flags);
-	/* add request to vc->desc_issued */
-	if (vchan_issue_pending(&c->vc)) {
-		spin_lock(&d->lock);
-		if (!c->phy && list_empty(&c->node)) {
-			/* if new channel, add chan_pending */
-			list_add_tail(&c->node, &d->chan_pending);
-			issue = 1;
-			dev_dbg(d->slave.dev, "vchan %p: issued\n", &c->vc);
-		}
-		spin_unlock(&d->lock);
-	} else {
-		dev_dbg(d->slave.dev, "vchan %p: nothing to issue\n", &c->vc);
-	}
-	spin_unlock_irqrestore(&c->vc.lock, flags);
-
-	if (issue)
-		zx_dma_task(d);
-}
-
-static void zx_dma_fill_desc(struct zx_dma_desc_sw *ds, dma_addr_t dst,
-			     dma_addr_t src, size_t len, u32 num, u32 ccfg)
-{
-	if ((num + 1) < ds->desc_num)
-		ds->desc_hw[num].lli = ds->desc_hw_lli + (num + 1) *
-			sizeof(struct zx_desc_hw);
-	ds->desc_hw[num].saddr = src;
-	ds->desc_hw[num].daddr = dst;
-	ds->desc_hw[num].src_x = len;
-	ds->desc_hw[num].ctr = ccfg;
-}
-
-static struct zx_dma_desc_sw *zx_alloc_desc_resource(int num,
-						     struct dma_chan *chan)
-{
-	struct zx_dma_chan *c = to_zx_chan(chan);
-	struct zx_dma_desc_sw *ds;
-	struct zx_dma_dev *d = to_zx_dma(chan->device);
-	int lli_limit = LLI_BLOCK_SIZE / sizeof(struct zx_desc_hw);
-
-	if (num > lli_limit) {
-		dev_dbg(chan->device->dev, "vch %p: sg num %d exceed max %d\n",
-			&c->vc, num, lli_limit);
-		return NULL;
-	}
-
-	ds = kzalloc(sizeof(*ds), GFP_ATOMIC);
-	if (!ds)
-		return NULL;
-
-	ds->desc_hw = dma_pool_zalloc(d->pool, GFP_NOWAIT, &ds->desc_hw_lli);
-	if (!ds->desc_hw) {
-		dev_dbg(chan->device->dev, "vch %p: dma alloc fail\n", &c->vc);
-		kfree(ds);
-		return NULL;
-	}
-	ds->desc_num = num;
-	return ds;
-}
-
-static enum zx_dma_burst_width zx_dma_burst_width(enum dma_slave_buswidth width)
-{
-	switch (width) {
-	case DMA_SLAVE_BUSWIDTH_1_BYTE:
-	case DMA_SLAVE_BUSWIDTH_2_BYTES:
-	case DMA_SLAVE_BUSWIDTH_4_BYTES:
-	case DMA_SLAVE_BUSWIDTH_8_BYTES:
-		return ffs(width) - 1;
-	default:
-		return ZX_DMA_WIDTH_32BIT;
-	}
-}
-
-static int zx_pre_config(struct zx_dma_chan *c, enum dma_transfer_direction dir)
-{
-	struct dma_slave_config *cfg = &c->slave_cfg;
-	enum zx_dma_burst_width src_width;
-	enum zx_dma_burst_width dst_width;
-	u32 maxburst = 0;
-
-	switch (dir) {
-	case DMA_MEM_TO_MEM:
-		c->ccfg = ZX_CH_ENABLE | ZX_SOFT_REQ
-			| ZX_SRC_BURST_LEN(ZX_MAX_BURST_LEN - 1)
-			| ZX_SRC_BURST_WIDTH(ZX_DMA_WIDTH_32BIT)
-			| ZX_DST_BURST_WIDTH(ZX_DMA_WIDTH_32BIT);
-		break;
-	case DMA_MEM_TO_DEV:
-		c->dev_addr = cfg->dst_addr;
-		/* dst len is calculated from src width, len and dst width.
-		 * We need make sure dst len not exceed MAX LEN.
-		 * Trailing single transaction that does not fill a full
-		 * burst also require identical src/dst data width.
-		 */
-		dst_width = zx_dma_burst_width(cfg->dst_addr_width);
-		maxburst = cfg->dst_maxburst;
-		maxburst = maxburst < ZX_MAX_BURST_LEN ?
-				maxburst : ZX_MAX_BURST_LEN;
-		c->ccfg = ZX_DST_FIFO_MODE | ZX_CH_ENABLE
-			| ZX_SRC_BURST_LEN(maxburst - 1)
-			| ZX_SRC_BURST_WIDTH(dst_width)
-			| ZX_DST_BURST_WIDTH(dst_width);
-		break;
-	case DMA_DEV_TO_MEM:
-		c->dev_addr = cfg->src_addr;
-		src_width = zx_dma_burst_width(cfg->src_addr_width);
-		maxburst = cfg->src_maxburst;
-		maxburst = maxburst < ZX_MAX_BURST_LEN ?
-				maxburst : ZX_MAX_BURST_LEN;
-		c->ccfg = ZX_SRC_FIFO_MODE | ZX_CH_ENABLE
-			| ZX_SRC_BURST_LEN(maxburst - 1)
-			| ZX_SRC_BURST_WIDTH(src_width)
-			| ZX_DST_BURST_WIDTH(src_width);
-		break;
-	default:
-		return -EINVAL;
-	}
-	return 0;
-}
-
-static struct dma_async_tx_descriptor *zx_dma_prep_memcpy(
-	struct dma_chan *chan,	dma_addr_t dst, dma_addr_t src,
-	size_t len, unsigned long flags)
-{
-	struct zx_dma_chan *c = to_zx_chan(chan);
-	struct zx_dma_desc_sw *ds;
-	size_t copy = 0;
-	int num = 0;
-
-	if (!len)
-		return NULL;
-
-	if (zx_pre_config(c, DMA_MEM_TO_MEM))
-		return NULL;
-
-	num = DIV_ROUND_UP(len, DMA_MAX_SIZE);
-
-	ds = zx_alloc_desc_resource(num, chan);
-	if (!ds)
-		return NULL;
-
-	ds->size = len;
-	num = 0;
-
-	do {
-		copy = min_t(size_t, len, DMA_MAX_SIZE);
-		zx_dma_fill_desc(ds, dst, src, copy, num++, c->ccfg);
-
-		src += copy;
-		dst += copy;
-		len -= copy;
-	} while (len);
-
-	c->cyclic = 0;
-	ds->desc_hw[num - 1].lli = 0;	/* end of link */
-	ds->desc_hw[num - 1].ctr |= ZX_IRQ_ENABLE_ALL;
-	return vchan_tx_prep(&c->vc, &ds->vd, flags);
-}
-
-static struct dma_async_tx_descriptor *zx_dma_prep_slave_sg(
-	struct dma_chan *chan, struct scatterlist *sgl, unsigned int sglen,
-	enum dma_transfer_direction dir, unsigned long flags, void *context)
-{
-	struct zx_dma_chan *c = to_zx_chan(chan);
-	struct zx_dma_desc_sw *ds;
-	size_t len, avail, total = 0;
-	struct scatterlist *sg;
-	dma_addr_t addr, src = 0, dst = 0;
-	int num = sglen, i;
-
-	if (!sgl)
-		return NULL;
-
-	if (zx_pre_config(c, dir))
-		return NULL;
-
-	for_each_sg(sgl, sg, sglen, i) {
-		avail = sg_dma_len(sg);
-		if (avail > DMA_MAX_SIZE)
-			num += DIV_ROUND_UP(avail, DMA_MAX_SIZE) - 1;
-	}
-
-	ds = zx_alloc_desc_resource(num, chan);
-	if (!ds)
-		return NULL;
-
-	c->cyclic = 0;
-	num = 0;
-	for_each_sg(sgl, sg, sglen, i) {
-		addr = sg_dma_address(sg);
-		avail = sg_dma_len(sg);
-		total += avail;
-
-		do {
-			len = min_t(size_t, avail, DMA_MAX_SIZE);
-
-			if (dir == DMA_MEM_TO_DEV) {
-				src = addr;
-				dst = c->dev_addr;
-			} else if (dir == DMA_DEV_TO_MEM) {
-				src = c->dev_addr;
-				dst = addr;
-			}
-
-			zx_dma_fill_desc(ds, dst, src, len, num++, c->ccfg);
-
-			addr += len;
-			avail -= len;
-		} while (avail);
-	}
-
-	ds->desc_hw[num - 1].lli = 0;	/* end of link */
-	ds->desc_hw[num - 1].ctr |= ZX_IRQ_ENABLE_ALL;
-	ds->size = total;
-	return vchan_tx_prep(&c->vc, &ds->vd, flags);
-}
-
-static struct dma_async_tx_descriptor *zx_dma_prep_dma_cyclic(
-		struct dma_chan *chan, dma_addr_t dma_addr, size_t buf_len,
-		size_t period_len, enum dma_transfer_direction dir,
-		unsigned long flags)
-{
-	struct zx_dma_chan *c = to_zx_chan(chan);
-	struct zx_dma_desc_sw *ds;
-	dma_addr_t src = 0, dst = 0;
-	int num_periods = buf_len / period_len;
-	int buf = 0, num = 0;
-
-	if (period_len > DMA_MAX_SIZE) {
-		dev_err(chan->device->dev, "maximum period size exceeded\n");
-		return NULL;
-	}
-
-	if (zx_pre_config(c, dir))
-		return NULL;
-
-	ds = zx_alloc_desc_resource(num_periods, chan);
-	if (!ds)
-		return NULL;
-	c->cyclic = 1;
-
-	while (buf < buf_len) {
-		if (dir == DMA_MEM_TO_DEV) {
-			src = dma_addr;
-			dst = c->dev_addr;
-		} else if (dir == DMA_DEV_TO_MEM) {
-			src = c->dev_addr;
-			dst = dma_addr;
-		}
-		zx_dma_fill_desc(ds, dst, src, period_len, num++,
-				 c->ccfg | ZX_IRQ_ENABLE_ALL);
-		dma_addr += period_len;
-		buf += period_len;
-	}
-
-	ds->desc_hw[num - 1].lli = ds->desc_hw_lli;
-	ds->size = buf_len;
-	return vchan_tx_prep(&c->vc, &ds->vd, flags);
-}
-
-static int zx_dma_config(struct dma_chan *chan,
-			 struct dma_slave_config *cfg)
-{
-	struct zx_dma_chan *c = to_zx_chan(chan);
-
-	if (!cfg)
-		return -EINVAL;
-
-	memcpy(&c->slave_cfg, cfg, sizeof(*cfg));
-
-	return 0;
-}
-
-static int zx_dma_terminate_all(struct dma_chan *chan)
-{
-	struct zx_dma_chan *c = to_zx_chan(chan);
-	struct zx_dma_dev *d = to_zx_dma(chan->device);
-	struct zx_dma_phy *p = c->phy;
-	unsigned long flags;
-	LIST_HEAD(head);
-
-	dev_dbg(d->slave.dev, "vchan %p: terminate all\n", &c->vc);
-
-	/* Prevent this channel being scheduled */
-	spin_lock(&d->lock);
-	list_del_init(&c->node);
-	spin_unlock(&d->lock);
-
-	/* Clear the tx descriptor lists */
-	spin_lock_irqsave(&c->vc.lock, flags);
-	vchan_get_all_descriptors(&c->vc, &head);
-	if (p) {
-		/* vchan is assigned to a pchan - stop the channel */
-		zx_dma_terminate_chan(p, d);
-		c->phy = NULL;
-		p->vchan = NULL;
-		p->ds_run = NULL;
-		p->ds_done = NULL;
-	}
-	spin_unlock_irqrestore(&c->vc.lock, flags);
-	vchan_dma_desc_free_list(&c->vc, &head);
-
-	return 0;
-}
-
-static int zx_dma_transfer_pause(struct dma_chan *chan)
-{
-	struct zx_dma_chan *c = to_zx_chan(chan);
-	u32 val = 0;
-
-	val = readl_relaxed(c->phy->base + REG_ZX_CTRL);
-	val &= ~ZX_CH_ENABLE;
-	writel_relaxed(val, c->phy->base + REG_ZX_CTRL);
-
-	return 0;
-}
-
-static int zx_dma_transfer_resume(struct dma_chan *chan)
-{
-	struct zx_dma_chan *c = to_zx_chan(chan);
-	u32 val = 0;
-
-	val = readl_relaxed(c->phy->base + REG_ZX_CTRL);
-	val |= ZX_CH_ENABLE;
-	writel_relaxed(val, c->phy->base + REG_ZX_CTRL);
-
-	return 0;
-}
-
-static void zx_dma_free_desc(struct virt_dma_desc *vd)
-{
-	struct zx_dma_desc_sw *ds =
-		container_of(vd, struct zx_dma_desc_sw, vd);
-	struct zx_dma_dev *d = to_zx_dma(vd->tx.chan->device);
-
-	dma_pool_free(d->pool, ds->desc_hw, ds->desc_hw_lli);
-	kfree(ds);
-}
-
-static const struct of_device_id zx6702_dma_dt_ids[] = {
-	{ .compatible = "zte,zx296702-dma", },
-	{}
-};
-MODULE_DEVICE_TABLE(of, zx6702_dma_dt_ids);
-
-static struct dma_chan *zx_of_dma_simple_xlate(struct of_phandle_args *dma_spec,
-					       struct of_dma *ofdma)
-{
-	struct zx_dma_dev *d = ofdma->of_dma_data;
-	unsigned int request = dma_spec->args[0];
-	struct dma_chan *chan;
-	struct zx_dma_chan *c;
-
-	if (request >= d->dma_requests)
-		return NULL;
-
-	chan = dma_get_any_slave_channel(&d->slave);
-	if (!chan) {
-		dev_err(d->slave.dev, "get channel fail in %s.\n", __func__);
-		return NULL;
-	}
-	c = to_zx_chan(chan);
-	c->id = request;
-	dev_info(d->slave.dev, "zx_dma: pchan %u: alloc vchan %p\n",
-		 c->id, &c->vc);
-	return chan;
-}
-
-static int zx_dma_probe(struct platform_device *op)
-{
-	struct zx_dma_dev *d;
-	int i, ret = 0;
-
-	d = devm_kzalloc(&op->dev, sizeof(*d), GFP_KERNEL);
-	if (!d)
-		return -ENOMEM;
-
-	d->base = devm_platform_ioremap_resource(op, 0);
-	if (IS_ERR(d->base))
-		return PTR_ERR(d->base);
-
-	of_property_read_u32((&op->dev)->of_node,
-			     "dma-channels", &d->dma_channels);
-	of_property_read_u32((&op->dev)->of_node,
-			     "dma-requests", &d->dma_requests);
-	if (!d->dma_requests || !d->dma_channels)
-		return -EINVAL;
-
-	d->clk = devm_clk_get(&op->dev, NULL);
-	if (IS_ERR(d->clk)) {
-		dev_err(&op->dev, "no dma clk\n");
-		return PTR_ERR(d->clk);
-	}
-
-	d->irq = platform_get_irq(op, 0);
-	ret = devm_request_irq(&op->dev, d->irq, zx_dma_int_handler,
-			       0, DRIVER_NAME, d);
-	if (ret)
-		return ret;
-
-	/* A DMA memory pool for LLIs, align on 32-byte boundary */
-	d->pool = dmam_pool_create(DRIVER_NAME, &op->dev,
-			LLI_BLOCK_SIZE, 32, 0);
-	if (!d->pool)
-		return -ENOMEM;
-
-	/* init phy channel */
-	d->phy = devm_kcalloc(&op->dev,
-		d->dma_channels, sizeof(struct zx_dma_phy), GFP_KERNEL);
-	if (!d->phy)
-		return -ENOMEM;
-
-	for (i = 0; i < d->dma_channels; i++) {
-		struct zx_dma_phy *p = &d->phy[i];
-
-		p->idx = i;
-		p->base = d->base + i * 0x40;
-	}
-
-	INIT_LIST_HEAD(&d->slave.channels);
-	dma_cap_set(DMA_SLAVE, d->slave.cap_mask);
-	dma_cap_set(DMA_MEMCPY, d->slave.cap_mask);
-	dma_cap_set(DMA_CYCLIC, d->slave.cap_mask);
-	dma_cap_set(DMA_PRIVATE, d->slave.cap_mask);
-	d->slave.dev = &op->dev;
-	d->slave.device_free_chan_resources = zx_dma_free_chan_resources;
-	d->slave.device_tx_status = zx_dma_tx_status;
-	d->slave.device_prep_dma_memcpy = zx_dma_prep_memcpy;
-	d->slave.device_prep_slave_sg = zx_dma_prep_slave_sg;
-	d->slave.device_prep_dma_cyclic = zx_dma_prep_dma_cyclic;
-	d->slave.device_issue_pending = zx_dma_issue_pending;
-	d->slave.device_config = zx_dma_config;
-	d->slave.device_terminate_all = zx_dma_terminate_all;
-	d->slave.device_pause = zx_dma_transfer_pause;
-	d->slave.device_resume = zx_dma_transfer_resume;
-	d->slave.copy_align = DMA_ALIGN;
-	d->slave.src_addr_widths = ZX_DMA_BUSWIDTHS;
-	d->slave.dst_addr_widths = ZX_DMA_BUSWIDTHS;
-	d->slave.directions = BIT(DMA_MEM_TO_MEM) | BIT(DMA_MEM_TO_DEV)
-			| BIT(DMA_DEV_TO_MEM);
-	d->slave.residue_granularity = DMA_RESIDUE_GRANULARITY_SEGMENT;
-
-	/* init virtual channel */
-	d->chans = devm_kcalloc(&op->dev,
-		d->dma_requests, sizeof(struct zx_dma_chan), GFP_KERNEL);
-	if (!d->chans)
-		return -ENOMEM;
-
-	for (i = 0; i < d->dma_requests; i++) {
-		struct zx_dma_chan *c = &d->chans[i];
-
-		c->status = DMA_IN_PROGRESS;
-		INIT_LIST_HEAD(&c->node);
-		c->vc.desc_free = zx_dma_free_desc;
-		vchan_init(&c->vc, &d->slave);
-	}
-
-	/* Enable clock before accessing registers */
-	ret = clk_prepare_enable(d->clk);
-	if (ret < 0) {
-		dev_err(&op->dev, "clk_prepare_enable failed: %d\n", ret);
-		goto zx_dma_out;
-	}
-
-	zx_dma_init_state(d);
-
-	spin_lock_init(&d->lock);
-	INIT_LIST_HEAD(&d->chan_pending);
-	platform_set_drvdata(op, d);
-
-	ret = dma_async_device_register(&d->slave);
-	if (ret)
-		goto clk_dis;
-
-	ret = of_dma_controller_register((&op->dev)->of_node,
-					 zx_of_dma_simple_xlate, d);
-	if (ret)
-		goto of_dma_register_fail;
-
-	dev_info(&op->dev, "initialized\n");
-	return 0;
-
-of_dma_register_fail:
-	dma_async_device_unregister(&d->slave);
-clk_dis:
-	clk_disable_unprepare(d->clk);
-zx_dma_out:
-	return ret;
-}
-
-static int zx_dma_remove(struct platform_device *op)
-{
-	struct zx_dma_chan *c, *cn;
-	struct zx_dma_dev *d = platform_get_drvdata(op);
-
-	/* explictly free the irq */
-	devm_free_irq(&op->dev, d->irq, d);
-
-	dma_async_device_unregister(&d->slave);
-	of_dma_controller_free((&op->dev)->of_node);
-
-	list_for_each_entry_safe(c, cn, &d->slave.channels,
-				 vc.chan.device_node) {
-		list_del(&c->vc.chan.device_node);
-	}
-	clk_disable_unprepare(d->clk);
-
-	return 0;
-}
-
-#ifdef CONFIG_PM_SLEEP
-static int zx_dma_suspend_dev(struct device *dev)
-{
-	struct zx_dma_dev *d = dev_get_drvdata(dev);
-	u32 stat = 0;
-
-	stat = zx_dma_get_chan_stat(d);
-	if (stat) {
-		dev_warn(d->slave.dev,
-			 "chan %d is running fail to suspend\n", stat);
-		return -1;
-	}
-	clk_disable_unprepare(d->clk);
-	return 0;
-}
-
-static int zx_dma_resume_dev(struct device *dev)
-{
-	struct zx_dma_dev *d = dev_get_drvdata(dev);
-	int ret = 0;
-
-	ret = clk_prepare_enable(d->clk);
-	if (ret < 0) {
-		dev_err(d->slave.dev, "clk_prepare_enable failed: %d\n", ret);
-		return ret;
-	}
-	zx_dma_init_state(d);
-	return 0;
-}
-#endif
-
-static SIMPLE_DEV_PM_OPS(zx_dma_pmops, zx_dma_suspend_dev, zx_dma_resume_dev);
-
-static struct platform_driver zx_pdma_driver = {
-	.driver		= {
-		.name	= DRIVER_NAME,
-		.pm	= &zx_dma_pmops,
-		.of_match_table = zx6702_dma_dt_ids,
-	},
-	.probe		= zx_dma_probe,
-	.remove		= zx_dma_remove,
-};
-
-module_platform_driver(zx_pdma_driver);
-
-MODULE_DESCRIPTION("ZTE ZX296702 DMA Driver");
-MODULE_AUTHOR("Jun Nie jun.nie@linaro.org");
-MODULE_LICENSE("GPL v2");
-- 
2.29.2