dmaengine: remove s3c24xx driver

The s3c24xx platform was removed and this driver is no longer
needed.

Reviewed-by: Krzysztof Kozlowski <[e-mail]>
Signed-off-by: Arnd Bergmann <[e-mail]>

drivers/dma/Kconfig

···
 	help
 	  Enable support for the on-chip DMA controller on Spreadtrum platform.
 
-config S3C24XX_DMAC
-	bool "Samsung S3C24XX DMA support"
-	depends on ARCH_S3C24XX || COMPILE_TEST
-	select DMA_ENGINE
-	select DMA_VIRTUAL_CHANNELS
-	help
-	  Support for the Samsung S3C24XX DMA controller driver. The
-	  DMA controller is having multiple DMA channels which can be
-	  configured for different peripherals like audio, UART, SPI.
-	  The DMA controller can transfer data from memory to peripheral,
-	  periphal to memory, periphal to periphal and memory to memory.
-
 config TXX9_DMAC
 	tristate "Toshiba TXx9 SoC DMA support"
 	depends on MACH_TX49XX

drivers/dma/Makefile

···
 obj-$(CONFIG_STM32_DMAMUX) += stm32-dmamux.o
 obj-$(CONFIG_STM32_MDMA) += stm32-mdma.o
 obj-$(CONFIG_SPRD_DMA) += sprd-dma.o
-obj-$(CONFIG_S3C24XX_DMAC) += s3c24xx-dma.o
 obj-$(CONFIG_TXX9_DMAC) += txx9dmac.o
 obj-$(CONFIG_TEGRA186_GPC_DMA) += tegra186-gpc-dma.o
 obj-$(CONFIG_TEGRA20_APB_DMA) += tegra20-apb-dma.o

drivers/dma/s3c24xx-dma.c

···
-// SPDX-License-Identifier: GPL-2.0-or-later
-/*
- * S3C24XX DMA handling
- *
- * Copyright (c) 2013 Heiko Stuebner <[e-mail]>
- *
- * based on amba-pl08x.c
- *
- * Copyright (c) 2006 ARM Ltd.
- * Copyright (c) 2010 ST-Ericsson SA
- *
- * Author: Peter Pearse <[e-mail]>
- * Author: Linus Walleij <[e-mail]>
- *
- * The DMA controllers in S3C24XX SoCs have a varying number of DMA signals
- * that can be routed to any of the 4 to 8 hardware-channels.
- *
- * Therefore on these DMA controllers the number of channels
- * and the number of incoming DMA signals are two totally different things.
- * It is usually not possible to theoretically handle all physical signals,
- * so a multiplexing scheme with possible denial of use is necessary.
- *
- * Open items:
- * - bursts
- */
-
-#include <linux/platform_device.h>
-#include <linux/types.h>
-#include <linux/dmaengine.h>
-#include <linux/dma-mapping.h>
-#include <linux/interrupt.h>
-#include <linux/clk.h>
-#include <linux/module.h>
-#include <linux/mod_devicetable.h>
-#include <linux/slab.h>
-#include <linux/platform_data/dma-s3c24xx.h>
-
-#include "dmaengine.h"
-#include "virt-dma.h"
-
-#define MAX_DMA_CHANNELS	8
-
-#define S3C24XX_DISRC			0x00
-#define S3C24XX_DISRCC			0x04
-#define S3C24XX_DISRCC_INC_INCREMENT	0
-#define S3C24XX_DISRCC_INC_FIXED	BIT(0)
-#define S3C24XX_DISRCC_LOC_AHB		0
-#define S3C24XX_DISRCC_LOC_APB		BIT(1)
-
-#define S3C24XX_DIDST			0x08
-#define S3C24XX_DIDSTC			0x0c
-#define S3C24XX_DIDSTC_INC_INCREMENT	0
-#define S3C24XX_DIDSTC_INC_FIXED	BIT(0)
-#define S3C24XX_DIDSTC_LOC_AHB		0
-#define S3C24XX_DIDSTC_LOC_APB		BIT(1)
-#define S3C24XX_DIDSTC_INT_TC0		0
-#define S3C24XX_DIDSTC_INT_RELOAD	BIT(2)
-
-#define S3C24XX_DCON			0x10
-
-#define S3C24XX_DCON_TC_MASK		0xfffff
-#define S3C24XX_DCON_DSZ_BYTE		(0 << 20)
-#define S3C24XX_DCON_DSZ_HALFWORD	(1 << 20)
-#define S3C24XX_DCON_DSZ_WORD		(2 << 20)
-#define S3C24XX_DCON_DSZ_MASK		(3 << 20)
-#define S3C24XX_DCON_DSZ_SHIFT		20
-#define S3C24XX_DCON_AUTORELOAD		0
-#define S3C24XX_DCON_NORELOAD		BIT(22)
-#define S3C24XX_DCON_HWTRIG		BIT(23)
-#define S3C24XX_DCON_HWSRC_SHIFT	24
-#define S3C24XX_DCON_SERV_SINGLE	0
-#define S3C24XX_DCON_SERV_WHOLE		BIT(27)
-#define S3C24XX_DCON_TSZ_UNIT		0
-#define S3C24XX_DCON_TSZ_BURST4		BIT(28)
-#define S3C24XX_DCON_INT		BIT(29)
-#define S3C24XX_DCON_SYNC_PCLK		0
-#define S3C24XX_DCON_SYNC_HCLK		BIT(30)
-#define S3C24XX_DCON_DEMAND		0
-#define S3C24XX_DCON_HANDSHAKE		BIT(31)
-
-#define S3C24XX_DSTAT			0x14
-#define S3C24XX_DSTAT_STAT_BUSY		BIT(20)
-#define S3C24XX_DSTAT_CURRTC_MASK	0xfffff
-
-#define S3C24XX_DMASKTRIG		0x20
-#define S3C24XX_DMASKTRIG_SWTRIG	BIT(0)
-#define S3C24XX_DMASKTRIG_ON		BIT(1)
-#define S3C24XX_DMASKTRIG_STOP		BIT(2)
-
-#define S3C24XX_DMAREQSEL		0x24
-#define S3C24XX_DMAREQSEL_HW		BIT(0)
-
-/*
- * S3C2410, S3C2440 and S3C2442 SoCs cannot select any physical channel
- * for a DMA source. Instead only specific channels are valid.
- * All of these SoCs have 4 physical channels and the number of request
- * source bits is 3. Additionally we also need 1 bit to mark the channel
- * as valid.
- * Therefore we separate the chansel element of the channel data into 4
- * parts of 4 bits each, to hold the information if the channel is valid
- * and the hw request source to use.
- *
- * Example:
- * SDI is valid on channels 0, 2 and 3 - with varying hw request sources.
- * For it the chansel field would look like
- *
- * ((BIT(3) | 1) << 3 * 4) | // channel 3, with request source 1
- * ((BIT(3) | 2) << 2 * 4) | // channel 2, with request source 2
- * ((BIT(3) | 2) << 0 * 4)   // channel 0, with request source 2
- */
-#define S3C24XX_CHANSEL_WIDTH		4
-#define S3C24XX_CHANSEL_VALID		BIT(3)
-#define S3C24XX_CHANSEL_REQ_MASK	7
-
-/*
- * struct soc_data - vendor-specific config parameters for individual SoCs
- * @stride: spacing between the registers of each channel
- * @has_reqsel: does the controller use the newer requestselection mechanism
- * @has_clocks: are controllable dma-clocks present
- */
-struct soc_data {
-	int stride;
-	bool has_reqsel;
-	bool has_clocks;
-};
-
-/*
- * enum s3c24xx_dma_chan_state - holds the virtual channel states
- * @S3C24XX_DMA_CHAN_IDLE: the channel is idle
- * @S3C24XX_DMA_CHAN_RUNNING: the channel has allocated a physical transport
- * channel and is running a transfer on it
- * @S3C24XX_DMA_CHAN_WAITING: the channel is waiting for a physical transport
- * channel to become available (only pertains to memcpy channels)
- */
-enum s3c24xx_dma_chan_state {
-	S3C24XX_DMA_CHAN_IDLE,
-	S3C24XX_DMA_CHAN_RUNNING,
-	S3C24XX_DMA_CHAN_WAITING,
-};
-
-/*
- * struct s3c24xx_sg - structure containing data per sg
- * @src_addr: src address of sg
- * @dst_addr: dst address of sg
- * @len: transfer len in bytes
- * @node: node for txd's dsg_list
- */
-struct s3c24xx_sg {
-	dma_addr_t src_addr;
-	dma_addr_t dst_addr;
-	size_t len;
-	struct list_head node;
-};
-
-/*
- * struct s3c24xx_txd - wrapper for struct dma_async_tx_descriptor
- * @vd: virtual DMA descriptor
- * @dsg_list: list of children sg's
- * @at: sg currently being transfered
- * @width: transfer width
- * @disrcc: value for source control register
- * @didstc: value for destination control register
- * @dcon: base value for dcon register
- * @cyclic: indicate cyclic transfer
- */
-struct s3c24xx_txd {
-	struct virt_dma_desc vd;
-	struct list_head dsg_list;
-	struct list_head *at;
-	u8 width;
-	u32 disrcc;
-	u32 didstc;
-	u32 dcon;
-	bool cyclic;
-};
-
-struct s3c24xx_dma_chan;
-
-/*
- * struct s3c24xx_dma_phy - holder for the physical channels
- * @id: physical index to this channel
- * @valid: does the channel have all required elements
- * @base: virtual memory base (remapped) for the this channel
- * @irq: interrupt for this channel
- * @clk: clock for this channel
- * @lock: a lock to use when altering an instance of this struct
- * @serving: virtual channel currently being served by this physicalchannel
- * @host: a pointer to the host (internal use)
- */
-struct s3c24xx_dma_phy {
-	unsigned int			id;
-	bool				valid;
-	void __iomem			*base;
-	int				irq;
-	struct clk			*clk;
-	spinlock_t			lock;
-	struct s3c24xx_dma_chan		*serving;
-	struct s3c24xx_dma_engine	*host;
-};
-
-/*
- * struct s3c24xx_dma_chan - this structure wraps a DMA ENGINE channel
- * @id: the id of the channel
- * @name: name of the channel
- * @vc: wrapped virtual channel
- * @phy: the physical channel utilized by this channel, if there is one
- * @runtime_addr: address for RX/TX according to the runtime config
- * @at: active transaction on this channel
- * @lock: a lock for this channel data
- * @host: a pointer to the host (internal use)
- * @state: whether the channel is idle, running etc
- * @slave: whether this channel is a device (slave) or for memcpy
- */
-struct s3c24xx_dma_chan {
-	int id;
-	const char *name;
-	struct virt_dma_chan vc;
-	struct s3c24xx_dma_phy *phy;
-	struct dma_slave_config cfg;
-	struct s3c24xx_txd *at;
-	struct s3c24xx_dma_engine *host;
-	enum s3c24xx_dma_chan_state state;
-	bool slave;
-};
-
-/*
- * struct s3c24xx_dma_engine - the local state holder for the S3C24XX
- * @pdev: the corresponding platform device
- * @pdata: platform data passed in from the platform/machine
- * @base: virtual memory base (remapped)
- * @slave: slave engine for this instance
- * @memcpy: memcpy engine for this instance
- * @phy_chans: array of data for the physical channels
- */
-struct s3c24xx_dma_engine {
-	struct platform_device			*pdev;
-	const struct s3c24xx_dma_platdata	*pdata;
-	struct soc_data				*sdata;
-	void __iomem				*base;
-	struct dma_device			slave;
-	struct dma_device			memcpy;
-	struct s3c24xx_dma_phy			*phy_chans;
-};
-
-/*
- * Physical channel handling
- */
-
-/*
- * Check whether a certain channel is busy or not.
- */
-static int s3c24xx_dma_phy_busy(struct s3c24xx_dma_phy *phy)
-{
-	unsigned int val = readl(phy->base + S3C24XX_DSTAT);
-	return val & S3C24XX_DSTAT_STAT_BUSY;
-}
-
-static bool s3c24xx_dma_phy_valid(struct s3c24xx_dma_chan *s3cchan,
-				  struct s3c24xx_dma_phy *phy)
-{
-	struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
-	const struct s3c24xx_dma_platdata *pdata = s3cdma->pdata;
-	struct s3c24xx_dma_channel *cdata = &pdata->channels[s3cchan->id];
-	int phyvalid;
-
-	/* every phy is valid for memcopy channels */
-	if (!s3cchan->slave)
-		return true;
-
-	/* On newer variants all phys can be used for all virtual channels */
-	if (s3cdma->sdata->has_reqsel)
-		return true;
-
-	phyvalid = (cdata->chansel >> (phy->id * S3C24XX_CHANSEL_WIDTH));
-	return (phyvalid & S3C24XX_CHANSEL_VALID) ? true : false;
-}
-
-/*
- * Allocate a physical channel for a virtual channel
- *
- * Try to locate a physical channel to be used for this transfer. If all
- * are taken return NULL and the requester will have to cope by using
- * some fallback PIO mode or retrying later.
- */
-static
-struct s3c24xx_dma_phy *s3c24xx_dma_get_phy(struct s3c24xx_dma_chan *s3cchan)
-{
-	struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
-	struct s3c24xx_dma_phy *phy = NULL;
-	unsigned long flags;
-	int i;
-	int ret;
-
-	for (i = 0; i < s3cdma->pdata->num_phy_channels; i++) {
-		phy = &s3cdma->phy_chans[i];
-
-		if (!phy->valid)
-			continue;
-
-		if (!s3c24xx_dma_phy_valid(s3cchan, phy))
-			continue;
-
-		spin_lock_irqsave(&phy->lock, flags);
-
-		if (!phy->serving) {
-			phy->serving = s3cchan;
-			spin_unlock_irqrestore(&phy->lock, flags);
-			break;
-		}
-
-		spin_unlock_irqrestore(&phy->lock, flags);
-	}
-
-	/* No physical channel available, cope with it */
-	if (i == s3cdma->pdata->num_phy_channels) {
-		dev_warn(&s3cdma->pdev->dev, "no phy channel available\n");
-		return NULL;
-	}
-
-	/* start the phy clock */
-	if (s3cdma->sdata->has_clocks) {
-		ret = clk_enable(phy->clk);
-		if (ret) {
-			dev_err(&s3cdma->pdev->dev, "could not enable clock for channel %d, err %d\n",
-				phy->id, ret);
-			phy->serving = NULL;
-			return NULL;
-		}
-	}
-
-	return phy;
-}
-
-/*
- * Mark the physical channel as free.
- *
- * This drops the link between the physical and virtual channel.
- */
-static inline void s3c24xx_dma_put_phy(struct s3c24xx_dma_phy *phy)
-{
-	struct s3c24xx_dma_engine *s3cdma = phy->host;
-
-	if (s3cdma->sdata->has_clocks)
-		clk_disable(phy->clk);
-
-	phy->serving = NULL;
-}
-
-/*
- * Stops the channel by writing the stop bit.
- * This should not be used for an on-going transfer, but as a method of
- * shutting down a channel (eg, when it's no longer used) or terminating a
- * transfer.
- */
-static void s3c24xx_dma_terminate_phy(struct s3c24xx_dma_phy *phy)
-{
-	writel(S3C24XX_DMASKTRIG_STOP, phy->base + S3C24XX_DMASKTRIG);
-}
-
-/*
- * Virtual channel handling
- */
-
-static inline
-struct s3c24xx_dma_chan *to_s3c24xx_dma_chan(struct dma_chan *chan)
-{
-	return container_of(chan, struct s3c24xx_dma_chan, vc.chan);
-}
-
-static u32 s3c24xx_dma_getbytes_chan(struct s3c24xx_dma_chan *s3cchan)
-{
-	struct s3c24xx_dma_phy *phy = s3cchan->phy;
-	struct s3c24xx_txd *txd = s3cchan->at;
-	u32 tc = readl(phy->base + S3C24XX_DSTAT) & S3C24XX_DSTAT_CURRTC_MASK;
-
-	return tc * txd->width;
-}
-
-static int s3c24xx_dma_set_runtime_config(struct dma_chan *chan,
-				  struct dma_slave_config *config)
-{
-	struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
-	unsigned long flags;
-	int ret = 0;
-
-	/* Reject definitely invalid configurations */
-	if (config->src_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES ||
-	    config->dst_addr_width == DMA_SLAVE_BUSWIDTH_8_BYTES)
-		return -EINVAL;
-
-	spin_lock_irqsave(&s3cchan->vc.lock, flags);
-
-	if (!s3cchan->slave) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	s3cchan->cfg = *config;
-
-out:
-	spin_unlock_irqrestore(&s3cchan->vc.lock, flags);
-	return ret;
-}
-
-/*
- * Transfer handling
- */
-
-static inline
-struct s3c24xx_txd *to_s3c24xx_txd(struct dma_async_tx_descriptor *tx)
-{
-	return container_of(tx, struct s3c24xx_txd, vd.tx);
-}
-
-static struct s3c24xx_txd *s3c24xx_dma_get_txd(void)
-{
-	struct s3c24xx_txd *txd = kzalloc(sizeof(*txd), GFP_NOWAIT);
-
-	if (txd) {
-		INIT_LIST_HEAD(&txd->dsg_list);
-		txd->dcon = S3C24XX_DCON_INT | S3C24XX_DCON_NORELOAD;
-	}
-
-	return txd;
-}
-
-static void s3c24xx_dma_free_txd(struct s3c24xx_txd *txd)
-{
-	struct s3c24xx_sg *dsg, *_dsg;
-
-	list_for_each_entry_safe(dsg, _dsg, &txd->dsg_list, node) {
-		list_del(&dsg->node);
-		kfree(dsg);
-	}
-
-	kfree(txd);
-}
-
-static void s3c24xx_dma_start_next_sg(struct s3c24xx_dma_chan *s3cchan,
-				       struct s3c24xx_txd *txd)
-{
-	struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
-	struct s3c24xx_dma_phy *phy = s3cchan->phy;
-	const struct s3c24xx_dma_platdata *pdata = s3cdma->pdata;
-	struct s3c24xx_sg *dsg = list_entry(txd->at, struct s3c24xx_sg, node);
-	u32 dcon = txd->dcon;
-	u32 val;
-
-	/* transfer-size and -count from len and width */
-	switch (txd->width) {
-	case 1:
-		dcon |= S3C24XX_DCON_DSZ_BYTE | dsg->len;
-		break;
-	case 2:
-		dcon |= S3C24XX_DCON_DSZ_HALFWORD | (dsg->len / 2);
-		break;
-	case 4:
-		dcon |= S3C24XX_DCON_DSZ_WORD | (dsg->len / 4);
-		break;
-	}
-
-	if (s3cchan->slave) {
-		struct s3c24xx_dma_channel *cdata =
-					&pdata->channels[s3cchan->id];
-
-		if (s3cdma->sdata->has_reqsel) {
-			writel_relaxed((cdata->chansel << 1) |
-							S3C24XX_DMAREQSEL_HW,
-					phy->base + S3C24XX_DMAREQSEL);
-		} else {
-			int csel = cdata->chansel >> (phy->id *
-							S3C24XX_CHANSEL_WIDTH);
-
-			csel &= S3C24XX_CHANSEL_REQ_MASK;
-			dcon |= csel << S3C24XX_DCON_HWSRC_SHIFT;
-			dcon |= S3C24XX_DCON_HWTRIG;
-		}
-	} else {
-		if (s3cdma->sdata->has_reqsel)
-			writel_relaxed(0, phy->base + S3C24XX_DMAREQSEL);
-	}
-
-	writel_relaxed(dsg->src_addr, phy->base + S3C24XX_DISRC);
-	writel_relaxed(txd->disrcc, phy->base + S3C24XX_DISRCC);
-	writel_relaxed(dsg->dst_addr, phy->base + S3C24XX_DIDST);
-	writel_relaxed(txd->didstc, phy->base + S3C24XX_DIDSTC);
-	writel_relaxed(dcon, phy->base + S3C24XX_DCON);
-
-	val = readl_relaxed(phy->base + S3C24XX_DMASKTRIG);
-	val &= ~S3C24XX_DMASKTRIG_STOP;
-	val |= S3C24XX_DMASKTRIG_ON;
-
-	/* trigger the dma operation for memcpy transfers */
-	if (!s3cchan->slave)
-		val |= S3C24XX_DMASKTRIG_SWTRIG;
-
-	writel(val, phy->base + S3C24XX_DMASKTRIG);
-}
-
-/*
- * Set the initial DMA register values and start first sg.
- */
-static void s3c24xx_dma_start_next_txd(struct s3c24xx_dma_chan *s3cchan)
-{
-	struct s3c24xx_dma_phy *phy = s3cchan->phy;
-	struct virt_dma_desc *vd = vchan_next_desc(&s3cchan->vc);
-	struct s3c24xx_txd *txd = to_s3c24xx_txd(&vd->tx);
-
-	list_del(&txd->vd.node);
-
-	s3cchan->at = txd;
-
-	/* Wait for channel inactive */
-	while (s3c24xx_dma_phy_busy(phy))
-		cpu_relax();
-
-	/* point to the first element of the sg list */
-	txd->at = txd->dsg_list.next;
-	s3c24xx_dma_start_next_sg(s3cchan, txd);
-}
-
-/*
- * Try to allocate a physical channel.  When successful, assign it to
- * this virtual channel, and initiate the next descriptor.  The
- * virtual channel lock must be held at this point.
- */
-static void s3c24xx_dma_phy_alloc_and_start(struct s3c24xx_dma_chan *s3cchan)
-{
-	struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
-	struct s3c24xx_dma_phy *phy;
-
-	phy = s3c24xx_dma_get_phy(s3cchan);
-	if (!phy) {
-		dev_dbg(&s3cdma->pdev->dev, "no physical channel available for xfer on %s\n",
-			s3cchan->name);
-		s3cchan->state = S3C24XX_DMA_CHAN_WAITING;
-		return;
-	}
-
-	dev_dbg(&s3cdma->pdev->dev, "allocated physical channel %d for xfer on %s\n",
-		phy->id, s3cchan->name);
-
-	s3cchan->phy = phy;
-	s3cchan->state = S3C24XX_DMA_CHAN_RUNNING;
-
-	s3c24xx_dma_start_next_txd(s3cchan);
-}
-
-static void s3c24xx_dma_phy_reassign_start(struct s3c24xx_dma_phy *phy,
-	struct s3c24xx_dma_chan *s3cchan)
-{
-	struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
-
-	dev_dbg(&s3cdma->pdev->dev, "reassigned physical channel %d for xfer on %s\n",
-		phy->id, s3cchan->name);
-
-	/*
-	 * We do this without taking the lock; we're really only concerned
-	 * about whether this pointer is NULL or not, and we're guaranteed
-	 * that this will only be called when it _already_ is non-NULL.
-	 */
-	phy->serving = s3cchan;
-	s3cchan->phy = phy;
-	s3cchan->state = S3C24XX_DMA_CHAN_RUNNING;
-	s3c24xx_dma_start_next_txd(s3cchan);
-}
-
-/*
- * Free a physical DMA channel, potentially reallocating it to another
- * virtual channel if we have any pending.
- */
-static void s3c24xx_dma_phy_free(struct s3c24xx_dma_chan *s3cchan)
-{
-	struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
-	struct s3c24xx_dma_chan *p, *next;
-
-retry:
-	next = NULL;
-
-	/* Find a waiting virtual channel for the next transfer. */
-	list_for_each_entry(p, &s3cdma->memcpy.channels, vc.chan.device_node)
-		if (p->state == S3C24XX_DMA_CHAN_WAITING) {
-			next = p;
-			break;
-		}
-
-	if (!next) {
-		list_for_each_entry(p, &s3cdma->slave.channels,
-				    vc.chan.device_node)
-			if (p->state == S3C24XX_DMA_CHAN_WAITING &&
-				      s3c24xx_dma_phy_valid(p, s3cchan->phy)) {
-				next = p;
-				break;
-			}
-	}
-
-	/* Ensure that the physical channel is stopped */
-	s3c24xx_dma_terminate_phy(s3cchan->phy);
-
-	if (next) {
-		bool success;
-
-		/*
-		 * Eww.  We know this isn't going to deadlock
-		 * but lockdep probably doesn't.
-		 */
-		spin_lock(&next->vc.lock);
-		/* Re-check the state now that we have the lock */
-		success = next->state == S3C24XX_DMA_CHAN_WAITING;
-		if (success)
-			s3c24xx_dma_phy_reassign_start(s3cchan->phy, next);
-		spin_unlock(&next->vc.lock);
-
-		/* If the state changed, try to find another channel */
-		if (!success)
-			goto retry;
-	} else {
-		/* No more jobs, so free up the physical channel */
-		s3c24xx_dma_put_phy(s3cchan->phy);
-	}
-
-	s3cchan->phy = NULL;
-	s3cchan->state = S3C24XX_DMA_CHAN_IDLE;
-}
-
-static void s3c24xx_dma_desc_free(struct virt_dma_desc *vd)
-{
-	struct s3c24xx_txd *txd = to_s3c24xx_txd(&vd->tx);
-	struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(vd->tx.chan);
-
-	if (!s3cchan->slave)
-		dma_descriptor_unmap(&vd->tx);
-
-	s3c24xx_dma_free_txd(txd);
-}
-
-static irqreturn_t s3c24xx_dma_irq(int irq, void *data)
-{
-	struct s3c24xx_dma_phy *phy = data;
-	struct s3c24xx_dma_chan *s3cchan = phy->serving;
-	struct s3c24xx_txd *txd;
-
-	dev_dbg(&phy->host->pdev->dev, "interrupt on channel %d\n", phy->id);
-
-	/*
-	 * Interrupts happen to notify the completion of a transfer and the
-	 * channel should have moved into its stop state already on its own.
-	 * Therefore interrupts on channels not bound to a virtual channel
-	 * should never happen. Nevertheless send a terminate command to the
-	 * channel if the unlikely case happens.
-	 */
-	if (unlikely(!s3cchan)) {
-		dev_err(&phy->host->pdev->dev, "interrupt on unused channel %d\n",
-			phy->id);
-
-		s3c24xx_dma_terminate_phy(phy);
-
-		return IRQ_HANDLED;
-	}
-
-	spin_lock(&s3cchan->vc.lock);
-	txd = s3cchan->at;
-	if (txd) {
-		/* when more sg's are in this txd, start the next one */
-		if (!list_is_last(txd->at, &txd->dsg_list)) {
-			txd->at = txd->at->next;
-			if (txd->cyclic)
-				vchan_cyclic_callback(&txd->vd);
-			s3c24xx_dma_start_next_sg(s3cchan, txd);
-		} else if (!txd->cyclic) {
-			s3cchan->at = NULL;
-			vchan_cookie_complete(&txd->vd);
-
-			/*
-			 * And start the next descriptor (if any),
-			 * otherwise free this channel.
-			 */
-			if (vchan_next_desc(&s3cchan->vc))
-				s3c24xx_dma_start_next_txd(s3cchan);
-			else
-				s3c24xx_dma_phy_free(s3cchan);
-		} else {
-			vchan_cyclic_callback(&txd->vd);
-
-			/* Cyclic: reset at beginning */
-			txd->at = txd->dsg_list.next;
-			s3c24xx_dma_start_next_sg(s3cchan, txd);
-		}
-	}
-	spin_unlock(&s3cchan->vc.lock);
-
-	return IRQ_HANDLED;
-}
-
-/*
- * The DMA ENGINE API
- */
-
-static int s3c24xx_dma_terminate_all(struct dma_chan *chan)
-{
-	struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
-	struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
-	LIST_HEAD(head);
-	unsigned long flags;
-	int ret;
-
-	spin_lock_irqsave(&s3cchan->vc.lock, flags);
-
-	if (!s3cchan->phy && !s3cchan->at) {
-		dev_err(&s3cdma->pdev->dev, "trying to terminate already stopped channel %d\n",
-			s3cchan->id);
-		ret = -EINVAL;
-		goto unlock;
-	}
-
-	s3cchan->state = S3C24XX_DMA_CHAN_IDLE;
-
-	/* Mark physical channel as free */
-	if (s3cchan->phy)
-		s3c24xx_dma_phy_free(s3cchan);
-
-	/* Dequeue current job */
-	if (s3cchan->at) {
-		vchan_terminate_vdesc(&s3cchan->at->vd);
-		s3cchan->at = NULL;
-	}
-
-	/* Dequeue jobs not yet fired as well */
-
-	vchan_get_all_descriptors(&s3cchan->vc, &head);
-
-	spin_unlock_irqrestore(&s3cchan->vc.lock, flags);
-
-	vchan_dma_desc_free_list(&s3cchan->vc, &head);
-
-	return 0;
-
-unlock:
-	spin_unlock_irqrestore(&s3cchan->vc.lock, flags);
-
-	return ret;
-}
-
-static void s3c24xx_dma_synchronize(struct dma_chan *chan)
-{
-	struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
-
-	vchan_synchronize(&s3cchan->vc);
-}
-
-static void s3c24xx_dma_free_chan_resources(struct dma_chan *chan)
-{
-	/* Ensure all queued descriptors are freed */
-	vchan_free_chan_resources(to_virt_chan(chan));
-}
-
-static enum dma_status s3c24xx_dma_tx_status(struct dma_chan *chan,
-		dma_cookie_t cookie, struct dma_tx_state *txstate)
-{
-	struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
-	struct s3c24xx_txd *txd;
-	struct s3c24xx_sg *dsg;
-	struct virt_dma_desc *vd;
-	unsigned long flags;
-	enum dma_status ret;
-	size_t bytes = 0;
-
-	spin_lock_irqsave(&s3cchan->vc.lock, flags);
-	ret = dma_cookie_status(chan, cookie, txstate);
-
-	/*
-	 * There's no point calculating the residue if there's
-	 * no txstate to store the value.
-	 */
-	if (ret == DMA_COMPLETE || !txstate) {
-		spin_unlock_irqrestore(&s3cchan->vc.lock, flags);
-		return ret;
-	}
-
-	vd = vchan_find_desc(&s3cchan->vc, cookie);
-	if (vd) {
-		/* On the issued list, so hasn't been processed yet */
-		txd = to_s3c24xx_txd(&vd->tx);
-
-		list_for_each_entry(dsg, &txd->dsg_list, node)
-			bytes += dsg->len;
-	} else {
-		/*
-		 * Currently running, so sum over the pending sg's and
-		 * the currently active one.
-		 */
-		txd = s3cchan->at;
-
-		dsg = list_entry(txd->at, struct s3c24xx_sg, node);
-		list_for_each_entry_from(dsg, &txd->dsg_list, node)
-			bytes += dsg->len;
-
-		bytes += s3c24xx_dma_getbytes_chan(s3cchan);
-	}
-	spin_unlock_irqrestore(&s3cchan->vc.lock, flags);
-
-	/*
-	 * This cookie not complete yet
-	 * Get number of bytes left in the active transactions and queue
-	 */
-	dma_set_residue(txstate, bytes);
-
-	/* Whether waiting or running, we're in progress */
-	return ret;
-}
-
-/*
- * Initialize a descriptor to be used by memcpy submit
- */
-static struct dma_async_tx_descriptor *s3c24xx_dma_prep_memcpy(
-		struct dma_chan *chan, dma_addr_t dest, dma_addr_t src,
-		size_t len, unsigned long flags)
-{
-	struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
-	struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
-	struct s3c24xx_txd *txd;
-	struct s3c24xx_sg *dsg;
-	int src_mod, dest_mod;
-
-	dev_dbg(&s3cdma->pdev->dev, "prepare memcpy of %zu bytes from %s\n",
-			len, s3cchan->name);
-
-	if ((len & S3C24XX_DCON_TC_MASK) != len) {
-		dev_err(&s3cdma->pdev->dev, "memcpy size %zu to large\n", len);
-		return NULL;
-	}
-
-	txd = s3c24xx_dma_get_txd();
-	if (!txd)
-		return NULL;
-
-	dsg = kzalloc(sizeof(*dsg), GFP_NOWAIT);
-	if (!dsg) {
-		s3c24xx_dma_free_txd(txd);
-		return NULL;
-	}
-	list_add_tail(&dsg->node, &txd->dsg_list);
-
-	dsg->src_addr = src;
-	dsg->dst_addr = dest;
-	dsg->len = len;
-
-	/*
-	 * Determine a suitable transfer width.
-	 * The DMA controller cannot fetch/store information which is not
-	 * naturally aligned on the bus, i.e., a 4 byte fetch must start at
-	 * an address divisible by 4 - more generally addr % width must be 0.
-	 */
-	src_mod = src % 4;
-	dest_mod = dest % 4;
-	switch (len % 4) {
-	case 0:
-		txd->width = (src_mod == 0 && dest_mod == 0) ? 4 : 1;
-		break;
-	case 2:
-		txd->width = ((src_mod == 2 || src_mod == 0) &&
-			      (dest_mod == 2 || dest_mod == 0)) ? 2 : 1;
-		break;
-	default:
-		txd->width = 1;
-		break;
-	}
-
-	txd->disrcc = S3C24XX_DISRCC_LOC_AHB | S3C24XX_DISRCC_INC_INCREMENT;
-	txd->didstc = S3C24XX_DIDSTC_LOC_AHB | S3C24XX_DIDSTC_INC_INCREMENT;
-	txd->dcon |= S3C24XX_DCON_DEMAND | S3C24XX_DCON_SYNC_HCLK |
-		     S3C24XX_DCON_SERV_WHOLE;
-
-	return vchan_tx_prep(&s3cchan->vc, &txd->vd, flags);
-}
-
-static struct dma_async_tx_descriptor *s3c24xx_dma_prep_dma_cyclic(
-	struct dma_chan *chan, dma_addr_t addr, size_t size, size_t period,
-	enum dma_transfer_direction direction, unsigned long flags)
-{
-	struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
-	struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
-	const struct s3c24xx_dma_platdata *pdata = s3cdma->pdata;
-	struct s3c24xx_dma_channel *cdata = &pdata->channels[s3cchan->id];
-	struct s3c24xx_txd *txd;
-	struct s3c24xx_sg *dsg;
-	unsigned sg_len;
-	dma_addr_t slave_addr;
-	u32 hwcfg = 0;
-	int i;
-
-	dev_dbg(&s3cdma->pdev->dev,
-		"prepare cyclic transaction of %zu bytes with period %zu from %s\n",
-		size, period, s3cchan->name);
-
-	if (!is_slave_direction(direction)) {
-		dev_err(&s3cdma->pdev->dev,
-			"direction %d unsupported\n", direction);
-		return NULL;
-	}
-
-	txd = s3c24xx_dma_get_txd();
-	if (!txd)
-		return NULL;
-
-	txd->cyclic = 1;
-
-	if (cdata->handshake)
-		txd->dcon |= S3C24XX_DCON_HANDSHAKE;
-
-	switch (cdata->bus) {
-	case S3C24XX_DMA_APB:
-		txd->dcon |= S3C24XX_DCON_SYNC_PCLK;
-		hwcfg |= S3C24XX_DISRCC_LOC_APB;
-		break;
-	case S3C24XX_DMA_AHB:
-		txd->dcon |= S3C24XX_DCON_SYNC_HCLK;
-		hwcfg |= S3C24XX_DISRCC_LOC_AHB;
-		break;
-	}
-
-	/*
-	 * Always assume our peripheral desintation is a fixed
-	 * address in memory.
-	 */
-	hwcfg |= S3C24XX_DISRCC_INC_FIXED;
-
-	/*
-	 * Individual dma operations are requested by the slave,
-	 * so serve only single atomic operations (S3C24XX_DCON_SERV_SINGLE).
-	 */
-	txd->dcon |= S3C24XX_DCON_SERV_SINGLE;
-
-	if (direction == DMA_MEM_TO_DEV) {
-		txd->disrcc = S3C24XX_DISRCC_LOC_AHB |
-			      S3C24XX_DISRCC_INC_INCREMENT;
-		txd->didstc = hwcfg;
-		slave_addr = s3cchan->cfg.dst_addr;
-		txd->width = s3cchan->cfg.dst_addr_width;
-	} else {
-		txd->disrcc = hwcfg;
-		txd->didstc = S3C24XX_DIDSTC_LOC_AHB |
-			      S3C24XX_DIDSTC_INC_INCREMENT;
-		slave_addr = s3cchan->cfg.src_addr;
-		txd->width = s3cchan->cfg.src_addr_width;
-	}
-
-	sg_len = size / period;
-
-	for (i = 0; i < sg_len; i++) {
-		dsg = kzalloc(sizeof(*dsg), GFP_NOWAIT);
-		if (!dsg) {
-			s3c24xx_dma_free_txd(txd);
-			return NULL;
-		}
-		list_add_tail(&dsg->node, &txd->dsg_list);
-
-		dsg->len = period;
-		/* Check last period length */
-		if (i == sg_len - 1)
-			dsg->len = size - period * i;
-		if (direction == DMA_MEM_TO_DEV) {
-			dsg->src_addr = addr + period * i;
-			dsg->dst_addr = slave_addr;
-		} else { /* DMA_DEV_TO_MEM */
-			dsg->src_addr = slave_addr;
-			dsg->dst_addr = addr + period * i;
-		}
-	}
-
-	return vchan_tx_prep(&s3cchan->vc, &txd->vd, flags);
-}
-
-static struct dma_async_tx_descriptor *s3c24xx_dma_prep_slave_sg(
-		struct dma_chan *chan, struct scatterlist *sgl,
-		unsigned int sg_len, enum dma_transfer_direction direction,
-		unsigned long flags, void *context)
-{
-	struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
-	struct s3c24xx_dma_engine *s3cdma = s3cchan->host;
-	const struct s3c24xx_dma_platdata *pdata = s3cdma->pdata;
-	struct s3c24xx_dma_channel *cdata = &pdata->channels[s3cchan->id];
-	struct s3c24xx_txd *txd;
-	struct s3c24xx_sg *dsg;
-	struct scatterlist *sg;
-	dma_addr_t slave_addr;
-	u32 hwcfg = 0;
-	int tmp;
-
-	dev_dbg(&s3cdma->pdev->dev, "prepare transaction of %d bytes from %s\n",
-			sg_dma_len(sgl), s3cchan->name);
-
-	txd = s3c24xx_dma_get_txd();
-	if (!txd)
-		return NULL;
-
-	if (cdata->handshake)
-		txd->dcon |= S3C24XX_DCON_HANDSHAKE;
-
-	switch (cdata->bus) {
-	case S3C24XX_DMA_APB:
-		txd->dcon |= S3C24XX_DCON_SYNC_PCLK;
-		hwcfg |= S3C24XX_DISRCC_LOC_APB;
-		break;
-	case S3C24XX_DMA_AHB:
-		txd->dcon |= S3C24XX_DCON_SYNC_HCLK;
-		hwcfg |= S3C24XX_DISRCC_LOC_AHB;
-		break;
-	}
-
-	/*
-	 * Always assume our peripheral desintation is a fixed
-	 * address in memory.
-	 */
-	hwcfg |= S3C24XX_DISRCC_INC_FIXED;
-
-	/*
-	 * Individual dma operations are requested by the slave,
-	 * so serve only single atomic operations (S3C24XX_DCON_SERV_SINGLE).
-	 */
-	txd->dcon |= S3C24XX_DCON_SERV_SINGLE;
-
-	if (direction == DMA_MEM_TO_DEV) {
-		txd->disrcc = S3C24XX_DISRCC_LOC_AHB |
-			      S3C24XX_DISRCC_INC_INCREMENT;
-		txd->didstc = hwcfg;
-		slave_addr = s3cchan->cfg.dst_addr;
-		txd->width = s3cchan->cfg.dst_addr_width;
-	} else if (direction == DMA_DEV_TO_MEM) {
-		txd->disrcc = hwcfg;
-		txd->didstc = S3C24XX_DIDSTC_LOC_AHB |
-			      S3C24XX_DIDSTC_INC_INCREMENT;
-		slave_addr = s3cchan->cfg.src_addr;
-		txd->width = s3cchan->cfg.src_addr_width;
-	} else {
-		s3c24xx_dma_free_txd(txd);
-		dev_err(&s3cdma->pdev->dev,
-			"direction %d unsupported\n", direction);
-		return NULL;
-	}
-
-	for_each_sg(sgl, sg, sg_len, tmp) {
-		dsg = kzalloc(sizeof(*dsg), GFP_NOWAIT);
-		if (!dsg) {
-			s3c24xx_dma_free_txd(txd);
-			return NULL;
-		}
-		list_add_tail(&dsg->node, &txd->dsg_list);
-
-		dsg->len = sg_dma_len(sg);
-		if (direction == DMA_MEM_TO_DEV) {
-			dsg->src_addr = sg_dma_address(sg);
-			dsg->dst_addr = slave_addr;
-		} else { /* DMA_DEV_TO_MEM */
-			dsg->src_addr = slave_addr;
-			dsg->dst_addr = sg_dma_address(sg);
-		}
-	}
-
-	return vchan_tx_prep(&s3cchan->vc, &txd->vd, flags);
-}
-
-/*
- * Slave transactions callback to the slave device to allow
- * synchronization of slave DMA signals with the DMAC enable
- */
-static void s3c24xx_dma_issue_pending(struct dma_chan *chan)
-{
-	struct s3c24xx_dma_chan *s3cchan = to_s3c24xx_dma_chan(chan);
-	unsigned long flags;
-
-	spin_lock_irqsave(&s3cchan->vc.lock, flags);
-	if (vchan_issue_pending(&s3cchan->vc)) {
-		if (!s3cchan->phy && s3cchan->state != S3C24XX_DMA_CHAN_WAITING)
-			s3c24xx_dma_phy_alloc_and_start(s3cchan);
-	}
-	spin_unlock_irqrestore(&s3cchan->vc.lock, flags);
-}
-
-/*
- * Bringup and teardown
- */
-
-/*
- * Initialise the DMAC memcpy/slave channels.
- * Make a local wrapper to hold required data
- */
-static int s3c24xx_dma_init_virtual_channels(struct s3c24xx_dma_engine *s3cdma,
-		struct dma_device *dmadev, unsigned int channels, bool slave)
-{
-	struct s3c24xx_dma_chan *chan;
-	int i;
-
-	INIT_LIST_HEAD(&dmadev->channels);
-
-	/*
-	 * Register as many memcpy as we have physical channels,
-	 * we won't always be able to use all but the code will have
-	 * to cope with that situation.
-	 */
-	for (i = 0; i < channels; i++) {
-		chan = devm_kzalloc(dmadev->dev, sizeof(*chan), GFP_KERNEL);
-		if (!chan)
-			return -ENOMEM;
-
-		chan->id = i;
-		chan->host = s3cdma;
-		chan->state = S3C24XX_DMA_CHAN_IDLE;
-
-		if (slave) {
-			chan->slave = true;
-			chan->name = kasprintf(GFP_KERNEL, "slave%d", i);
-			if (!chan->name)
-				return -ENOMEM;
-		} else {
-			chan->name = kasprintf(GFP_KERNEL, "memcpy%d", i);
-			if (!chan->name)
-				return -ENOMEM;
-		}
-		dev_dbg(dmadev->dev,
-			 "initialize virtual channel \"%s\"\n",
-			 chan->name);
-
-		chan->vc.desc_free = s3c24xx_dma_desc_free;
-		vchan_init(&chan->vc, dmadev);
-	}
-	dev_info(dmadev->dev, "initialized %d virtual %s channels\n",
-		 i, slave ? "slave" : "memcpy");
-	return i;
-}
-
-static void s3c24xx_dma_free_virtual_channels(struct dma_device *dmadev)
-{
-	struct s3c24xx_dma_chan *chan = NULL;
-	struct s3c24xx_dma_chan *next;
-
-	list_for_each_entry_safe(chan,
-				 next, &dmadev->channels, vc.chan.device_node) {
-		list_del(&chan->vc.chan.device_node);
-		tasklet_kill(&chan->vc.task);
-	}
-}
-
-/* s3c2410, s3c2440 and s3c2442 have a 0x40 stride without separate clocks */
-static struct soc_data soc_s3c2410 = {
-	.stride = 0x40,
-	.has_reqsel = false,
-	.has_clocks = false,
-};
-
-/* s3c2412 and s3c2413 have a 0x40 stride and dmareqsel mechanism */
-static struct soc_data soc_s3c2412 = {
-	.stride = 0x40,
-	.has_reqsel = true,
-	.has_clocks = true,
-};
-
-/* s3c2443 and following have a 0x100 stride and dmareqsel mechanism */
-static struct soc_data soc_s3c2443 = {
-	.stride = 0x100,
-	.has_reqsel = true,
-	.has_clocks = true,
-};
-
-static const struct platform_device_id s3c24xx_dma_driver_ids[] = {
-	{
-		.name		= "s3c2410-dma",
-		.driver_data	= (kernel_ulong_t)&soc_s3c2410,
-	}, {
-		.name		= "s3c2412-dma",
-		.driver_data	= (kernel_ulong_t)&soc_s3c2412,
-	}, {
-		.name		= "s3c2443-dma",
-		.driver_data	= (kernel_ulong_t)&soc_s3c2443,
-	},
-	{ },
-};
-
-static struct soc_data *s3c24xx_dma_get_soc_data(struct platform_device *pdev)
-{
-	return (struct soc_data *)
-			 platform_get_device_id(pdev)->driver_data;
-}
-
-static int s3c24xx_dma_probe(struct platform_device *pdev)
-{
-	const struct s3c24xx_dma_platdata *pdata = dev_get_platdata(&pdev->dev);
-	struct s3c24xx_dma_engine *s3cdma;
-	struct soc_data *sdata;
-	struct resource *res;
-	int ret;
-	int i;
-
-	if (!pdata) {
-		dev_err(&pdev->dev, "platform data missing\n");
-		return -ENODEV;
-	}
-
-	/* Basic sanity check */
-	if (pdata->num_phy_channels > MAX_DMA_CHANNELS) {
-		dev_err(&pdev->dev, "too many dma channels %d, max %d\n",
-			pdata->num_phy_channels, MAX_DMA_CHANNELS);
-		return -EINVAL;
-	}
-
-	sdata = s3c24xx_dma_get_soc_data(pdev);
-	if (!sdata)
-		return -EINVAL;
-
-	s3cdma = devm_kzalloc(&pdev->dev, sizeof(*s3cdma), GFP_KERNEL);
-	if (!s3cdma)
-		return -ENOMEM;
-
-	s3cdma->pdev = pdev;
-	s3cdma->pdata = pdata;
-	s3cdma->sdata = sdata;
-
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	s3cdma->base = devm_ioremap_resource(&pdev->dev, res);
-	if (IS_ERR(s3cdma->base))
-		return PTR_ERR(s3cdma->base);
-
-	s3cdma->phy_chans = devm_kcalloc(&pdev->dev,
-					      pdata->num_phy_channels,
-					      sizeof(struct s3c24xx_dma_phy),
-					      GFP_KERNEL);
-	if (!s3cdma->phy_chans)
-		return -ENOMEM;
-
-	/* acquire irqs and clocks for all physical channels */
-	for (i = 0; i < pdata->num_phy_channels; i++) {
-		struct s3c24xx_dma_phy *phy = &s3cdma->phy_chans[i];
-		char clk_name[6];
-
-		phy->id = i;
-		phy->base = s3cdma->base + (i * sdata->stride);
-		phy->host = s3cdma;
-
-		phy->irq = platform_get_irq(pdev, i);
-		if (phy->irq < 0)
-			continue;
-
-		ret = devm_request_irq(&pdev->dev, phy->irq, s3c24xx_dma_irq,
-				       0, pdev->name, phy);
-		if (ret) {
-			dev_err(&pdev->dev, "Unable to request irq for channel %d, error %d\n",
-				i, ret);
-			continue;
-		}
-
-		if (sdata->has_clocks) {
-			sprintf(clk_name, "dma.%d", i);
-			phy->clk = devm_clk_get(&pdev->dev, clk_name);
-			if (IS_ERR(phy->clk) && sdata->has_clocks) {
-				dev_err(&pdev->dev, "unable to acquire clock for channel %d, error %lu\n",
-					i, PTR_ERR(phy->clk));
-				continue;
-			}
-
-			ret = clk_prepare(phy->clk);
-			if (ret) {
-				dev_err(&pdev->dev, "clock for phy %d failed, error %d\n",
-					i, ret);
-				continue;
-			}
-		}
-
-		spin_lock_init(&phy->lock);
-		phy->valid = true;
-
-		dev_dbg(&pdev->dev, "physical channel %d is %s\n",
-			i, s3c24xx_dma_phy_busy(phy) ? "BUSY" : "FREE");
-	}
-
-	/* Initialize memcpy engine */
-	dma_cap_set(DMA_MEMCPY, s3cdma->memcpy.cap_mask);
-	dma_cap_set(DMA_PRIVATE, s3cdma->memcpy.cap_mask);
-	s3cdma->memcpy.dev = &pdev->dev;
-	s3cdma->memcpy.device_free_chan_resources =
-					s3c24xx_dma_free_chan_resources;
-	s3cdma->memcpy.device_prep_dma_memcpy = s3c24xx_dma_prep_memcpy;
-	s3cdma->memcpy.device_tx_status = s3c24xx_dma_tx_status;
-	s3cdma->memcpy.device_issue_pending = s3c24xx_dma_issue_pending;
-	s3cdma->memcpy.device_config = s3c24xx_dma_set_runtime_config;
-	s3cdma->memcpy.device_terminate_all = s3c24xx_dma_terminate_all;
-	s3cdma->memcpy.device_synchronize = s3c24xx_dma_synchronize;
-
-	/* Initialize slave engine for SoC internal dedicated peripherals */
-	dma_cap_set(DMA_SLAVE, s3cdma->slave.cap_mask);
-	dma_cap_set(DMA_CYCLIC, s3cdma->slave.cap_mask);
-	dma_cap_set(DMA_PRIVATE, s3cdma->slave.cap_mask);
-	s3cdma->slave.dev = &pdev->dev;
-	s3cdma->slave.device_free_chan_resources =
-					s3c24xx_dma_free_chan_resources;
-	s3cdma->slave.device_tx_status = s3c24xx_dma_tx_status;
-	s3cdma->slave.device_issue_pending = s3c24xx_dma_issue_pending;
-	s3cdma->slave.device_prep_slave_sg = s3c24xx_dma_prep_slave_sg;
-	s3cdma->slave.device_prep_dma_cyclic = s3c24xx_dma_prep_dma_cyclic;
-	s3cdma->slave.device_config = s3c24xx_dma_set_runtime_config;
-	s3cdma->slave.device_terminate_all = s3c24xx_dma_terminate_all;
-	s3cdma->slave.device_synchronize = s3c24xx_dma_synchronize;
-	s3cdma->slave.filter.map = pdata->slave_map;
-	s3cdma->slave.filter.mapcnt = pdata->slavecnt;
-	s3cdma->slave.filter.fn = s3c24xx_dma_filter;
-
-	/* Register as many memcpy channels as there are physical channels */
-	ret = s3c24xx_dma_init_virtual_channels(s3cdma, &s3cdma->memcpy,
-						pdata->num_phy_channels, false);
-	if (ret <= 0) {
-		dev_warn(&pdev->dev,
-			 "%s failed to enumerate memcpy channels - %d\n",
-			 __func__, ret);
-		goto err_memcpy;
-	}
-
-	/* Register slave channels */
-	ret = s3c24xx_dma_init_virtual_channels(s3cdma, &s3cdma->slave,
-				pdata->num_channels, true);
-	if (ret <= 0) {
-		dev_warn(&pdev->dev,
-			"%s failed to enumerate slave channels - %d\n",
-				__func__, ret);
-		goto err_slave;
-	}
-
-	ret = dma_async_device_register(&s3cdma->memcpy);
-	if (ret) {
-		dev_warn(&pdev->dev,
-			"%s failed to register memcpy as an async device - %d\n",
-			__func__, ret);
-		goto err_memcpy_reg;
-	}
-
-	ret = dma_async_device_register(&s3cdma->slave);
-	if (ret) {
-		dev_warn(&pdev->dev,
-			"%s failed to register slave as an async device - %d\n",
-			__func__, ret);
-		goto err_slave_reg;
-	}
-
-	platform_set_drvdata(pdev, s3cdma);
-	dev_info(&pdev->dev, "Loaded dma driver with %d physical channels\n",
-		 pdata->num_phy_channels);
-
-	return 0;
-
-err_slave_reg:
-	dma_async_device_unregister(&s3cdma->memcpy);
-err_memcpy_reg:
-	s3c24xx_dma_free_virtual_channels(&s3cdma->slave);
-err_slave:
-	s3c24xx_dma_free_virtual_channels(&s3cdma->memcpy);
-err_memcpy:
-	if (sdata->has_clocks)
-		for (i = 0; i < pdata->num_phy_channels; i++) {
-			struct s3c24xx_dma_phy *phy = &s3cdma->phy_chans[i];
-			if (phy->valid)
-				clk_unprepare(phy->clk);
-		}
-
-	return ret;
-}
-
-static void s3c24xx_dma_free_irq(struct platform_device *pdev,
-				struct s3c24xx_dma_engine *s3cdma)
-{
-	int i;
-
-	for (i = 0; i < s3cdma->pdata->num_phy_channels; i++) {
-		struct s3c24xx_dma_phy *phy = &s3cdma->phy_chans[i];
-
-		devm_free_irq(&pdev->dev, phy->irq, phy);
-	}
-}
-
-static int s3c24xx_dma_remove(struct platform_device *pdev)
-{
-	const struct s3c24xx_dma_platdata *pdata = dev_get_platdata(&pdev->dev);
-	struct s3c24xx_dma_engine *s3cdma = platform_get_drvdata(pdev);
-	struct soc_data *sdata = s3c24xx_dma_get_soc_data(pdev);
-	int i;
-
-	dma_async_device_unregister(&s3cdma->slave);
-	dma_async_device_unregister(&s3cdma->memcpy);
-
-	s3c24xx_dma_free_irq(pdev, s3cdma);
-
-	s3c24xx_dma_free_virtual_channels(&s3cdma->slave);
-	s3c24xx_dma_free_virtual_channels(&s3cdma->memcpy);
-
-	if (sdata->has_clocks)
-		for (i = 0; i < pdata->num_phy_channels; i++) {
-			struct s3c24xx_dma_phy *phy = &s3cdma->phy_chans[i];
-			if (phy->valid)
-				clk_unprepare(phy->clk);
-		}
-
-	return 0;
-}
-
-static struct platform_driver s3c24xx_dma_driver = {
-	.driver		= {
-		.name	= "s3c24xx-dma",
-	},
-	.id_table	= s3c24xx_dma_driver_ids,
-	.probe		= s3c24xx_dma_probe,
-	.remove		= s3c24xx_dma_remove,
-};
-
-module_platform_driver(s3c24xx_dma_driver);
-
-bool s3c24xx_dma_filter(struct dma_chan *chan, void *param)
-{
-	struct s3c24xx_dma_chan *s3cchan;
-
-	if (chan->device->dev->driver != &s3c24xx_dma_driver.driver)
-		return false;
-
-	s3cchan = to_s3c24xx_dma_chan(chan);
-
-	return s3cchan->id == (uintptr_t)param;
-}
-EXPORT_SYMBOL(s3c24xx_dma_filter);
-
-MODULE_DESCRIPTION("S3C24XX DMA Driver");
-MODULE_AUTHOR("Heiko Stuebner");
-MODULE_LICENSE("GPL v2");

include/linux/platform_data/dma-s3c24xx.h

···
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/*
- * S3C24XX DMA handling
- *
- * Copyright (c) 2013 Heiko Stuebner <[e-mail]>
- */
-
-/* Helper to encode the source selection constraints for early s3c socs. */
-#define S3C24XX_DMA_CHANREQ(src, chan)	((BIT(3) | src) << chan * 4)
-
-enum s3c24xx_dma_bus {
-	S3C24XX_DMA_APB,
-	S3C24XX_DMA_AHB,
-};
-
-/**
- * @bus: on which bus does the peripheral reside - AHB or APB.
- * @handshake: is a handshake with the peripheral necessary
- * @chansel: channel selection information, depending on variant; reqsel for
- *	     s3c2443 and later and channel-selection map for earlier SoCs
- *	     see CHANSEL doc in s3c2443-dma.c
- */
-struct s3c24xx_dma_channel {
-	enum s3c24xx_dma_bus bus;
-	bool handshake;
-	u16 chansel;
-};
-
-struct dma_slave_map;
-
-/**
- * struct s3c24xx_dma_platdata - platform specific settings
- * @num_phy_channels: number of physical channels
- * @channels: array of virtual channel descriptions
- * @num_channels: number of virtual channels
- * @slave_map: dma slave map matching table
- * @slavecnt: number of elements in slave_map
- */
-struct s3c24xx_dma_platdata {
-	int num_phy_channels;
-	struct s3c24xx_dma_channel *channels;
-	int num_channels;
-	const struct dma_slave_map *slave_map;
-	int slavecnt;
-};
-
-struct dma_chan;
-bool s3c24xx_dma_filter(struct dma_chan *chan, void *param);