dma: add driver for R-Car HPB-DMAC

Add support for HPB-DMAC found in Renesas R-Car SoCs, using 'shdma-base' DMA
driver framework.

Based on the original patch by Phil Edworthy <phil.edworthy@renesas.com>.

Signed-off-by: Max Filippov <max.filippov@cogentembedded.com>
[Sergei: removed useless #include, sorted #include's, fixed HPB_DMA_TCR_MAX,
fixed formats and removed line breaks in the dev_dbg() calls, rephrased and
added IRQ # to the shdma_request_irq() failure message, added MODULE_AUTHOR(),
removed '__init'/'__exit' annotations from the probe()/remove() methods, removed
'__initdata' annotation from 'hpb_dmae_driver', fixed guard macro name in the
header file, fixed #define ASYNCRSTR_ASRST20, added #define ASYNCRSTR_ASRST24,
added the necessary runtime PM calls to the probe() and remove() methods,
handled errors returned by dma_async_device_register(), beautified comments
and #define's.]
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>

4 files changed, 765 insertions, 0 deletions

diff --git a/drivers/dma/sh/Kconfig b/drivers/dma/sh/Kconfig
index 5c1dee20c13e..e2b94d16f41f 100644
--- a/drivers/dma/sh/Kconfig
+++ b/drivers/dma/sh/Kconfig
@@ -22,3 +22,9 @@ config SUDMAC
 	depends on SH_DMAE_BASE
 	help
 	  Enable support for the Renesas SUDMAC controllers.
+
+config RCAR_HPB_DMAE
+	tristate "Renesas R-Car HPB DMAC support"
+	depends on SH_DMAE_BASE
+	help
+	  Enable support for the Renesas R-Car series DMA controllers.
diff --git a/drivers/dma/sh/Makefile b/drivers/dma/sh/Makefile
index c962138dde96..ccf17cb5af10 100644
--- a/drivers/dma/sh/Makefile
+++ b/drivers/dma/sh/Makefile
@@ -1,3 +1,4 @@
 obj-$(CONFIG_SH_DMAE_BASE) += shdma-base.o shdma-of.o
 obj-$(CONFIG_SH_DMAE) += shdma.o
 obj-$(CONFIG_SUDMAC) += sudmac.o
+obj-$(CONFIG_RCAR_HPB_DMAE) += rcar-hpbdma.o
diff --git a/drivers/dma/sh/rcar-hpbdma.c b/drivers/dma/sh/rcar-hpbdma.c
new file mode 100644
index 000000000000..45a520281ce1
--- /dev/null
+++ b/drivers/dma/sh/rcar-hpbdma.c
@@ -0,0 +1,655 @@
+/*
+ * Copyright (C) 2011-2013 Renesas Electronics Corporation
+ * Copyright (C) 2013 Cogent Embedded, Inc.
+ *
+ * This file is based on the drivers/dma/sh/shdma.c
+ *
+ * Renesas SuperH DMA Engine support
+ *
+ * This 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.
+ *
+ * - DMA of SuperH does not have Hardware DMA chain mode.
+ * - max DMA size is 16MB.
+ *
+ */
+
+#include <linux/dmaengine.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/platform_data/dma-rcar-hpbdma.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/shdma-base.h>
+#include <linux/slab.h>
+
+/* DMA channel registers */
+#define HPB_DMAE_DSAR0	0x00
+#define HPB_DMAE_DDAR0	0x04
+#define HPB_DMAE_DTCR0	0x08
+#define HPB_DMAE_DSAR1	0x0C
+#define HPB_DMAE_DDAR1	0x10
+#define HPB_DMAE_DTCR1	0x14
+#define HPB_DMAE_DSASR	0x18
+#define HPB_DMAE_DDASR	0x1C
+#define HPB_DMAE_DTCSR	0x20
+#define HPB_DMAE_DPTR	0x24
+#define HPB_DMAE_DCR	0x28
+#define HPB_DMAE_DCMDR	0x2C
+#define HPB_DMAE_DSTPR	0x30
+#define HPB_DMAE_DSTSR	0x34
+#define HPB_DMAE_DDBGR	0x38
+#define HPB_DMAE_DDBGR2	0x3C
+#define HPB_DMAE_CHAN(n)	(0x40 * (n))
+
+/* DMA command register (DCMDR) bits */
+#define HPB_DMAE_DCMDR_BDOUT	BIT(7)
+#define HPB_DMAE_DCMDR_DQSPD	BIT(6)
+#define HPB_DMAE_DCMDR_DQSPC	BIT(5)
+#define HPB_DMAE_DCMDR_DMSPD	BIT(4)
+#define HPB_DMAE_DCMDR_DMSPC	BIT(3)
+#define HPB_DMAE_DCMDR_DQEND	BIT(2)
+#define HPB_DMAE_DCMDR_DNXT	BIT(1)
+#define HPB_DMAE_DCMDR_DMEN	BIT(0)
+
+/* DMA forced stop register (DSTPR) bits */
+#define HPB_DMAE_DSTPR_DMSTP	BIT(0)
+
+/* DMA status register (DSTSR) bits */
+#define HPB_DMAE_DSTSR_DMSTS	BIT(0)
+
+/* DMA common registers */
+#define HPB_DMAE_DTIMR		0x00
+#define HPB_DMAE_DINTSR0		0x0C
+#define HPB_DMAE_DINTSR1		0x10
+#define HPB_DMAE_DINTCR0		0x14
+#define HPB_DMAE_DINTCR1		0x18
+#define HPB_DMAE_DINTMR0		0x1C
+#define HPB_DMAE_DINTMR1		0x20
+#define HPB_DMAE_DACTSR0		0x24
+#define HPB_DMAE_DACTSR1		0x28
+#define HPB_DMAE_HSRSTR(n)	(0x40 + (n) * 4)
+#define HPB_DMAE_HPB_DMASPR(n)	(0x140 + (n) * 4)
+#define HPB_DMAE_HPB_DMLVLR0	0x160
+#define HPB_DMAE_HPB_DMLVLR1	0x164
+#define HPB_DMAE_HPB_DMSHPT0	0x168
+#define HPB_DMAE_HPB_DMSHPT1	0x16C
+
+#define HPB_DMA_SLAVE_NUMBER 256
+#define HPB_DMA_TCR_MAX 0x01000000	/* 16 MiB */
+
+struct hpb_dmae_chan {
+	struct shdma_chan shdma_chan;
+	int xfer_mode;			/* DMA transfer mode */
+#define XFER_SINGLE	1
+#define XFER_DOUBLE	2
+	unsigned plane_idx;		/* current DMA information set */
+	bool first_desc;		/* first/next transfer */
+	int xmit_shift;			/* log_2(bytes_per_xfer) */
+	void __iomem *base;
+	const struct hpb_dmae_slave_config *cfg;
+	char dev_id[16];		/* unique name per DMAC of channel */
+};
+
+struct hpb_dmae_device {
+	struct shdma_dev shdma_dev;
+	spinlock_t reg_lock;		/* comm_reg operation lock */
+	struct hpb_dmae_pdata *pdata;
+	void __iomem *chan_reg;
+	void __iomem *comm_reg;
+	void __iomem *reset_reg;
+	void __iomem *mode_reg;
+};
+
+struct hpb_dmae_regs {
+	u32 sar; /* SAR / source address */
+	u32 dar; /* DAR / destination address */
+	u32 tcr; /* TCR / transfer count */
+};
+
+struct hpb_desc {
+	struct shdma_desc shdma_desc;
+	struct hpb_dmae_regs hw;
+	unsigned plane_idx;
+};
+
+#define to_chan(schan) container_of(schan, struct hpb_dmae_chan, shdma_chan)
+#define to_desc(sdesc) container_of(sdesc, struct hpb_desc, shdma_desc)
+#define to_dev(sc) container_of(sc->shdma_chan.dma_chan.device, \
+				struct hpb_dmae_device, shdma_dev.dma_dev)
+
+static void ch_reg_write(struct hpb_dmae_chan *hpb_dc, u32 data, u32 reg)
+{
+	iowrite32(data, hpb_dc->base + reg);
+}
+
+static u32 ch_reg_read(struct hpb_dmae_chan *hpb_dc, u32 reg)
+{
+	return ioread32(hpb_dc->base + reg);
+}
+
+static void dcmdr_write(struct hpb_dmae_device *hpbdev, u32 data)
+{
+	iowrite32(data, hpbdev->chan_reg + HPB_DMAE_DCMDR);
+}
+
+static void hsrstr_write(struct hpb_dmae_device *hpbdev, u32 ch)
+{
+	iowrite32(0x1, hpbdev->comm_reg + HPB_DMAE_HSRSTR(ch));
+}
+
+static u32 dintsr_read(struct hpb_dmae_device *hpbdev, u32 ch)
+{
+	u32 v;
+
+	if (ch < 32)
+		v = ioread32(hpbdev->comm_reg + HPB_DMAE_DINTSR0) >> ch;
+	else
+		v = ioread32(hpbdev->comm_reg + HPB_DMAE_DINTSR1) >> (ch - 32);
+	return v & 0x1;
+}
+
+static void dintcr_write(struct hpb_dmae_device *hpbdev, u32 ch)
+{
+	if (ch < 32)
+		iowrite32((0x1 << ch), hpbdev->comm_reg + HPB_DMAE_DINTCR0);
+	else
+		iowrite32((0x1 << (ch - 32)),
+			  hpbdev->comm_reg + HPB_DMAE_DINTCR1);
+}
+
+static void asyncmdr_write(struct hpb_dmae_device *hpbdev, u32 data)
+{
+	iowrite32(data, hpbdev->mode_reg);
+}
+
+static u32 asyncmdr_read(struct hpb_dmae_device *hpbdev)
+{
+	return ioread32(hpbdev->mode_reg);
+}
+
+static void hpb_dmae_enable_int(struct hpb_dmae_device *hpbdev, u32 ch)
+{
+	u32 intreg;
+
+	spin_lock_irq(&hpbdev->reg_lock);
+	if (ch < 32) {
+		intreg = ioread32(hpbdev->comm_reg + HPB_DMAE_DINTMR0);
+		iowrite32(BIT(ch) | intreg,
+			  hpbdev->comm_reg + HPB_DMAE_DINTMR0);
+	} else {
+		intreg = ioread32(hpbdev->comm_reg + HPB_DMAE_DINTMR1);
+		iowrite32(BIT(ch - 32) | intreg,
+			  hpbdev->comm_reg + HPB_DMAE_DINTMR1);
+	}
+	spin_unlock_irq(&hpbdev->reg_lock);
+}
+
+static void hpb_dmae_async_reset(struct hpb_dmae_device *hpbdev, u32 data)
+{
+	u32 rstr;
+	int timeout = 10000;	/* 100 ms */
+
+	spin_lock(&hpbdev->reg_lock);
+	rstr = ioread32(hpbdev->reset_reg);
+	rstr |= data;
+	iowrite32(rstr, hpbdev->reset_reg);
+	do {
+		rstr = ioread32(hpbdev->reset_reg);
+		if ((rstr & data) == data)
+			break;
+		udelay(10);
+	} while (timeout--);
+
+	if (timeout < 0)
+		dev_err(hpbdev->shdma_dev.dma_dev.dev,
+			"%s timeout\n", __func__);
+
+	rstr &= ~data;
+	iowrite32(rstr, hpbdev->reset_reg);
+	spin_unlock(&hpbdev->reg_lock);
+}
+
+static void hpb_dmae_set_async_mode(struct hpb_dmae_device *hpbdev,
+				    u32 mask, u32 data)
+{
+	u32 mode;
+
+	spin_lock_irq(&hpbdev->reg_lock);
+	mode = asyncmdr_read(hpbdev);
+	mode &= ~mask;
+	mode |= data;
+	asyncmdr_write(hpbdev, mode);
+	spin_unlock_irq(&hpbdev->reg_lock);
+}
+
+static void hpb_dmae_ctl_stop(struct hpb_dmae_device *hpbdev)
+{
+	dcmdr_write(hpbdev, HPB_DMAE_DCMDR_DQSPD);
+}
+
+static void hpb_dmae_reset(struct hpb_dmae_device *hpbdev)
+{
+	u32 ch;
+
+	for (ch = 0; ch < hpbdev->pdata->num_hw_channels; ch++)
+		hsrstr_write(hpbdev, ch);
+}
+
+static unsigned int calc_xmit_shift(struct hpb_dmae_chan *hpb_chan)
+{
+	struct hpb_dmae_device *hpbdev = to_dev(hpb_chan);
+	struct hpb_dmae_pdata *pdata = hpbdev->pdata;
+	int width = ch_reg_read(hpb_chan, HPB_DMAE_DCR);
+	int i;
+
+	switch (width & (HPB_DMAE_DCR_SPDS_MASK | HPB_DMAE_DCR_DPDS_MASK)) {
+	case HPB_DMAE_DCR_SPDS_8BIT | HPB_DMAE_DCR_DPDS_8BIT:
+	default:
+		i = XMIT_SZ_8BIT;
+		break;
+	case HPB_DMAE_DCR_SPDS_16BIT | HPB_DMAE_DCR_DPDS_16BIT:
+		i = XMIT_SZ_16BIT;
+		break;
+	case HPB_DMAE_DCR_SPDS_32BIT | HPB_DMAE_DCR_DPDS_32BIT:
+		i = XMIT_SZ_32BIT;
+		break;
+	}
+	return pdata->ts_shift[i];
+}
+
+static void hpb_dmae_set_reg(struct hpb_dmae_chan *hpb_chan,
+			     struct hpb_dmae_regs *hw, unsigned plane)
+{
+	ch_reg_write(hpb_chan, hw->sar,
+		     plane ? HPB_DMAE_DSAR1 : HPB_DMAE_DSAR0);
+	ch_reg_write(hpb_chan, hw->dar,
+		     plane ? HPB_DMAE_DDAR1 : HPB_DMAE_DDAR0);
+	ch_reg_write(hpb_chan, hw->tcr >> hpb_chan->xmit_shift,
+		     plane ? HPB_DMAE_DTCR1 : HPB_DMAE_DTCR0);
+}
+
+static void hpb_dmae_start(struct hpb_dmae_chan *hpb_chan, bool next)
+{
+	ch_reg_write(hpb_chan, (next ? HPB_DMAE_DCMDR_DNXT : 0) |
+		     HPB_DMAE_DCMDR_DMEN, HPB_DMAE_DCMDR);
+}
+
+static void hpb_dmae_halt(struct shdma_chan *schan)
+{
+	struct hpb_dmae_chan *chan = to_chan(schan);
+
+	ch_reg_write(chan, HPB_DMAE_DCMDR_DQEND, HPB_DMAE_DCMDR);
+	ch_reg_write(chan, HPB_DMAE_DSTPR_DMSTP, HPB_DMAE_DSTPR);
+}
+
+static const struct hpb_dmae_slave_config *
+hpb_dmae_find_slave(struct hpb_dmae_chan *hpb_chan, int slave_id)
+{
+	struct hpb_dmae_device *hpbdev = to_dev(hpb_chan);
+	struct hpb_dmae_pdata *pdata = hpbdev->pdata;
+	int i;
+
+	if (slave_id >= HPB_DMA_SLAVE_NUMBER)
+		return NULL;
+
+	for (i = 0; i < pdata->num_slaves; i++)
+		if (pdata->slaves[i].id == slave_id)
+			return pdata->slaves + i;
+
+	return NULL;
+}
+
+static void hpb_dmae_start_xfer(struct shdma_chan *schan,
+				struct shdma_desc *sdesc)
+{
+	struct hpb_dmae_chan *chan = to_chan(schan);
+	struct hpb_dmae_device *hpbdev = to_dev(chan);
+	struct hpb_desc *desc = to_desc(sdesc);
+
+	if (chan->cfg->flags & HPB_DMAE_SET_ASYNC_RESET)
+		hpb_dmae_async_reset(hpbdev, chan->cfg->rstr);
+
+	desc->plane_idx = chan->plane_idx;
+	hpb_dmae_set_reg(chan, &desc->hw, chan->plane_idx);
+	hpb_dmae_start(chan, !chan->first_desc);
+
+	if (chan->xfer_mode == XFER_DOUBLE) {
+		chan->plane_idx ^= 1;
+		chan->first_desc = false;
+	}
+}
+
+static bool hpb_dmae_desc_completed(struct shdma_chan *schan,
+				    struct shdma_desc *sdesc)
+{
+	/*
+	 * This is correct since we always have at most single
+	 * outstanding DMA transfer per channel, and by the time
+	 * we get completion interrupt the transfer is completed.
+	 * This will change if we ever use alternating DMA
+	 * information sets and submit two descriptors at once.
+	 */
+	return true;
+}
+
+static bool hpb_dmae_chan_irq(struct shdma_chan *schan, int irq)
+{
+	struct hpb_dmae_chan *chan = to_chan(schan);
+	struct hpb_dmae_device *hpbdev = to_dev(chan);
+	int ch = chan->cfg->dma_ch;
+
+	/* Check Complete DMA Transfer */
+	if (dintsr_read(hpbdev, ch)) {
+		/* Clear Interrupt status */
+		dintcr_write(hpbdev, ch);
+		return true;
+	}
+	return false;
+}
+
+static int hpb_dmae_desc_setup(struct shdma_chan *schan,
+			       struct shdma_desc *sdesc,
+			       dma_addr_t src, dma_addr_t dst, size_t *len)
+{
+	struct hpb_desc *desc = to_desc(sdesc);
+
+	if (*len > (size_t)HPB_DMA_TCR_MAX)
+		*len = (size_t)HPB_DMA_TCR_MAX;
+
+	desc->hw.sar = src;
+	desc->hw.dar = dst;
+	desc->hw.tcr = *len;
+
+	return 0;
+}
+
+static size_t hpb_dmae_get_partial(struct shdma_chan *schan,
+				   struct shdma_desc *sdesc)
+{
+	struct hpb_desc *desc = to_desc(sdesc);
+	struct hpb_dmae_chan *chan = to_chan(schan);
+	u32 tcr = ch_reg_read(chan, desc->plane_idx ?
+			      HPB_DMAE_DTCR1 : HPB_DMAE_DTCR0);
+
+	return (desc->hw.tcr - tcr) << chan->xmit_shift;
+}
+
+static bool hpb_dmae_channel_busy(struct shdma_chan *schan)
+{
+	struct hpb_dmae_chan *chan = to_chan(schan);
+	u32 dstsr = ch_reg_read(chan, HPB_DMAE_DSTSR);
+
+	return (dstsr & HPB_DMAE_DSTSR_DMSTS) == HPB_DMAE_DSTSR_DMSTS;
+}
+
+static int
+hpb_dmae_alloc_chan_resources(struct hpb_dmae_chan *hpb_chan,
+			      const struct hpb_dmae_slave_config *cfg)
+{
+	struct hpb_dmae_device *hpbdev = to_dev(hpb_chan);
+	struct hpb_dmae_pdata *pdata = hpbdev->pdata;
+	const struct hpb_dmae_channel *channel = pdata->channels;
+	int slave_id = cfg->id;
+	int i, err;
+
+	for (i = 0; i < pdata->num_channels; i++, channel++) {
+		if (channel->s_id == slave_id) {
+			struct device *dev = hpb_chan->shdma_chan.dev;
+
+			hpb_chan->base = hpbdev->chan_reg +
+				HPB_DMAE_CHAN(cfg->dma_ch);
+
+			dev_dbg(dev, "Detected Slave device\n");
+			dev_dbg(dev, " -- slave_id       : 0x%x\n", slave_id);
+			dev_dbg(dev, " -- cfg->dma_ch    : %d\n", cfg->dma_ch);
+			dev_dbg(dev, " -- channel->ch_irq: %d\n",
+				channel->ch_irq);
+			break;
+		}
+	}
+
+	err = shdma_request_irq(&hpb_chan->shdma_chan, channel->ch_irq,
+				IRQF_SHARED, hpb_chan->dev_id);
+	if (err) {
+		dev_err(hpb_chan->shdma_chan.dev,
+			"DMA channel request_irq %d failed with error %d\n",
+			channel->ch_irq, err);
+		return err;
+	}
+
+	hpb_chan->plane_idx = 0;
+	hpb_chan->first_desc = true;
+
+	if ((cfg->dcr & (HPB_DMAE_DCR_CT | HPB_DMAE_DCR_DIP)) == 0) {
+		hpb_chan->xfer_mode = XFER_SINGLE;
+	} else if ((cfg->dcr & (HPB_DMAE_DCR_CT | HPB_DMAE_DCR_DIP)) ==
+		   (HPB_DMAE_DCR_CT | HPB_DMAE_DCR_DIP)) {
+		hpb_chan->xfer_mode = XFER_DOUBLE;
+	} else {
+		dev_err(hpb_chan->shdma_chan.dev, "DCR setting error");
+		shdma_free_irq(&hpb_chan->shdma_chan);
+		return -EINVAL;
+	}
+
+	if (cfg->flags & HPB_DMAE_SET_ASYNC_MODE)
+		hpb_dmae_set_async_mode(hpbdev, cfg->mdm, cfg->mdr);
+	ch_reg_write(hpb_chan, cfg->dcr, HPB_DMAE_DCR);
+	ch_reg_write(hpb_chan, cfg->port, HPB_DMAE_DPTR);
+	hpb_chan->xmit_shift = calc_xmit_shift(hpb_chan);
+	hpb_dmae_enable_int(hpbdev, cfg->dma_ch);
+
+	return 0;
+}
+
+static int hpb_dmae_set_slave(struct shdma_chan *schan, int slave_id, bool try)
+{
+	struct hpb_dmae_chan *chan = to_chan(schan);
+	const struct hpb_dmae_slave_config *sc =
+		hpb_dmae_find_slave(chan, slave_id);
+
+	if (!sc)
+		return -ENODEV;
+	if (try)
+		return 0;
+	chan->cfg = sc;
+	return hpb_dmae_alloc_chan_resources(chan, sc);
+}
+
+static void hpb_dmae_setup_xfer(struct shdma_chan *schan, int slave_id)
+{
+}
+
+static dma_addr_t hpb_dmae_slave_addr(struct shdma_chan *schan)
+{
+	struct hpb_dmae_chan *chan = to_chan(schan);
+
+	return chan->cfg->addr;
+}
+
+static struct shdma_desc *hpb_dmae_embedded_desc(void *buf, int i)
+{
+	return &((struct hpb_desc *)buf)[i].shdma_desc;
+}
+
+static const struct shdma_ops hpb_dmae_ops = {
+	.desc_completed = hpb_dmae_desc_completed,
+	.halt_channel = hpb_dmae_halt,
+	.channel_busy = hpb_dmae_channel_busy,
+	.slave_addr = hpb_dmae_slave_addr,
+	.desc_setup = hpb_dmae_desc_setup,
+	.set_slave = hpb_dmae_set_slave,
+	.setup_xfer = hpb_dmae_setup_xfer,
+	.start_xfer = hpb_dmae_start_xfer,
+	.embedded_desc = hpb_dmae_embedded_desc,
+	.chan_irq = hpb_dmae_chan_irq,
+	.get_partial = hpb_dmae_get_partial,
+};
+
+static int hpb_dmae_chan_probe(struct hpb_dmae_device *hpbdev, int id)
+{
+	struct shdma_dev *sdev = &hpbdev->shdma_dev;
+	struct platform_device *pdev =
+		to_platform_device(hpbdev->shdma_dev.dma_dev.dev);
+	struct hpb_dmae_chan *new_hpb_chan;
+	struct shdma_chan *schan;
+
+	/* Alloc channel */
+	new_hpb_chan = devm_kzalloc(&pdev->dev,
+				    sizeof(struct hpb_dmae_chan), GFP_KERNEL);
+	if (!new_hpb_chan) {
+		dev_err(hpbdev->shdma_dev.dma_dev.dev,
+			"No free memory for allocating DMA channels!\n");
+		return -ENOMEM;
+	}
+
+	schan = &new_hpb_chan->shdma_chan;
+	shdma_chan_probe(sdev, schan, id);
+
+	if (pdev->id >= 0)
+		snprintf(new_hpb_chan->dev_id, sizeof(new_hpb_chan->dev_id),
+			 "hpb-dmae%d.%d", pdev->id, id);
+	else
+		snprintf(new_hpb_chan->dev_id, sizeof(new_hpb_chan->dev_id),
+			 "hpb-dma.%d", id);
+
+	return 0;
+}
+
+static int hpb_dmae_probe(struct platform_device *pdev)
+{
+	struct hpb_dmae_pdata *pdata = pdev->dev.platform_data;
+	struct hpb_dmae_device *hpbdev;
+	struct dma_device *dma_dev;
+	struct resource *chan, *comm, *rest, *mode, *irq_res;
+	int err, i;
+
+	/* Get platform data */
+	if (!pdata || !pdata->num_channels)
+		return -ENODEV;
+
+	chan = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	comm = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	rest = platform_get_resource(pdev, IORESOURCE_MEM, 2);
+	mode = platform_get_resource(pdev, IORESOURCE_MEM, 3);
+
+	irq_res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (!irq_res)
+		return -ENODEV;
+
+	hpbdev = devm_kzalloc(&pdev->dev, sizeof(struct hpb_dmae_device),
+			      GFP_KERNEL);
+	if (!hpbdev) {
+		dev_err(&pdev->dev, "Not enough memory\n");
+		return -ENOMEM;
+	}
+
+	hpbdev->chan_reg = devm_ioremap_resource(&pdev->dev, chan);
+	if (IS_ERR(hpbdev->chan_reg))
+		return PTR_ERR(hpbdev->chan_reg);
+
+	hpbdev->comm_reg = devm_ioremap_resource(&pdev->dev, comm);
+	if (IS_ERR(hpbdev->comm_reg))
+		return PTR_ERR(hpbdev->comm_reg);
+
+	hpbdev->reset_reg = devm_ioremap_resource(&pdev->dev, rest);
+	if (IS_ERR(hpbdev->reset_reg))
+		return PTR_ERR(hpbdev->reset_reg);
+
+	hpbdev->mode_reg = devm_ioremap_resource(&pdev->dev, mode);
+	if (IS_ERR(hpbdev->mode_reg))
+		return PTR_ERR(hpbdev->mode_reg);
+
+	dma_dev = &hpbdev->shdma_dev.dma_dev;
+
+	spin_lock_init(&hpbdev->reg_lock);
+
+	/* Platform data */
+	hpbdev->pdata = pdata;
+
+	pm_runtime_enable(&pdev->dev);
+	err = pm_runtime_get_sync(&pdev->dev);
+	if (err < 0)
+		dev_err(&pdev->dev, "%s(): GET = %d\n", __func__, err);
+
+	/* Reset DMA controller */
+	hpb_dmae_reset(hpbdev);
+
+	pm_runtime_put(&pdev->dev);
+
+	dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask);
+	dma_cap_set(DMA_SLAVE, dma_dev->cap_mask);
+
+	hpbdev->shdma_dev.ops = &hpb_dmae_ops;
+	hpbdev->shdma_dev.desc_size = sizeof(struct hpb_desc);
+	err = shdma_init(&pdev->dev, &hpbdev->shdma_dev, pdata->num_channels);
+	if (err < 0)
+		goto error;
+
+	/* Create DMA channels */
+	for (i = 0; i < pdata->num_channels; i++)
+		hpb_dmae_chan_probe(hpbdev, i);
+
+	platform_set_drvdata(pdev, hpbdev);
+	err = dma_async_device_register(dma_dev);
+	if (!err)
+		return 0;
+
+	shdma_cleanup(&hpbdev->shdma_dev);
+error:
+	pm_runtime_disable(&pdev->dev);
+	return err;
+}
+
+static void hpb_dmae_chan_remove(struct hpb_dmae_device *hpbdev)
+{
+	struct dma_device *dma_dev = &hpbdev->shdma_dev.dma_dev;
+	struct shdma_chan *schan;
+	int i;
+
+	shdma_for_each_chan(schan, &hpbdev->shdma_dev, i) {
+		BUG_ON(!schan);
+
+		shdma_free_irq(schan);
+		shdma_chan_remove(schan);
+	}
+	dma_dev->chancnt = 0;
+}
+
+static int hpb_dmae_remove(struct platform_device *pdev)
+{
+	struct hpb_dmae_device *hpbdev = platform_get_drvdata(pdev);
+
+	dma_async_device_unregister(&hpbdev->shdma_dev.dma_dev);
+
+	pm_runtime_disable(&pdev->dev);
+
+	hpb_dmae_chan_remove(hpbdev);
+
+	return 0;
+}
+
+static void hpb_dmae_shutdown(struct platform_device *pdev)
+{
+	struct hpb_dmae_device *hpbdev = platform_get_drvdata(pdev);
+	hpb_dmae_ctl_stop(hpbdev);
+}
+
+static struct platform_driver hpb_dmae_driver = {
+	.probe		= hpb_dmae_probe,
+	.remove		= hpb_dmae_remove,
+	.shutdown	= hpb_dmae_shutdown,
+	.driver = {
+		.owner	= THIS_MODULE,
+		.name	= "hpb-dma-engine",
+	},
+};
+module_platform_driver(hpb_dmae_driver);
+
+MODULE_AUTHOR("Max Filippov <max.filippov@cogentembedded.com>");
+MODULE_DESCRIPTION("Renesas HPB DMA Engine driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/platform_data/dma-rcar-hpbdma.h b/include/linux/platform_data/dma-rcar-hpbdma.h
new file mode 100644
index 000000000000..648b8ea61a22
--- /dev/null
+++ b/include/linux/platform_data/dma-rcar-hpbdma.h
@@ -0,0 +1,103 @@
+/*
+ * Copyright (C) 2011-2013 Renesas Electronics Corporation
+ * Copyright (C) 2013 Cogent Embedded, Inc.
+ *
+ * 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 __DMA_RCAR_HPBDMA_H
+#define __DMA_RCAR_HPBDMA_H
+
+#include <linux/bitops.h>
+#include <linux/types.h>
+
+/* Transmit sizes and respective register values */
+enum {
+	XMIT_SZ_8BIT	= 0,
+	XMIT_SZ_16BIT	= 1,
+	XMIT_SZ_32BIT	= 2,
+	XMIT_SZ_MAX
+};
+
+/* DMA control register (DCR) bits */
+#define HPB_DMAE_DCR_DTAMD		(1u << 26)
+#define HPB_DMAE_DCR_DTAC		(1u << 25)
+#define HPB_DMAE_DCR_DTAU		(1u << 24)
+#define HPB_DMAE_DCR_DTAU1		(1u << 23)
+#define HPB_DMAE_DCR_SWMD		(1u << 22)
+#define HPB_DMAE_DCR_BTMD		(1u << 21)
+#define HPB_DMAE_DCR_PKMD		(1u << 20)
+#define HPB_DMAE_DCR_CT			(1u << 18)
+#define HPB_DMAE_DCR_ACMD		(1u << 17)
+#define HPB_DMAE_DCR_DIP		(1u << 16)
+#define HPB_DMAE_DCR_SMDL		(1u << 13)
+#define HPB_DMAE_DCR_SPDAM		(1u << 12)
+#define HPB_DMAE_DCR_SDRMD_MASK		(3u << 10)
+#define HPB_DMAE_DCR_SDRMD_MOD		(0u << 10)
+#define HPB_DMAE_DCR_SDRMD_AUTO		(1u << 10)
+#define HPB_DMAE_DCR_SDRMD_TIMER	(2u << 10)
+#define HPB_DMAE_DCR_SPDS_MASK		(3u << 8)
+#define HPB_DMAE_DCR_SPDS_8BIT		(0u << 8)
+#define HPB_DMAE_DCR_SPDS_16BIT		(1u << 8)
+#define HPB_DMAE_DCR_SPDS_32BIT		(2u << 8)
+#define HPB_DMAE_DCR_DMDL		(1u << 5)
+#define HPB_DMAE_DCR_DPDAM		(1u << 4)
+#define HPB_DMAE_DCR_DDRMD_MASK		(3u << 2)
+#define HPB_DMAE_DCR_DDRMD_MOD		(0u << 2)
+#define HPB_DMAE_DCR_DDRMD_AUTO		(1u << 2)
+#define HPB_DMAE_DCR_DDRMD_TIMER	(2u << 2)
+#define HPB_DMAE_DCR_DPDS_MASK		(3u << 0)
+#define HPB_DMAE_DCR_DPDS_8BIT		(0u << 0)
+#define HPB_DMAE_DCR_DPDS_16BIT		(1u << 0)
+#define HPB_DMAE_DCR_DPDS_32BIT		(2u << 0)
+
+/* Asynchronous reset register (ASYNCRSTR) bits */
+#define HPB_DMAE_ASYNCRSTR_ASRST41	BIT(10)
+#define HPB_DMAE_ASYNCRSTR_ASRST40	BIT(9)
+#define HPB_DMAE_ASYNCRSTR_ASRST39	BIT(8)
+#define HPB_DMAE_ASYNCRSTR_ASRST27	BIT(7)
+#define HPB_DMAE_ASYNCRSTR_ASRST26	BIT(6)
+#define HPB_DMAE_ASYNCRSTR_ASRST25	BIT(5)
+#define HPB_DMAE_ASYNCRSTR_ASRST24	BIT(4)
+#define HPB_DMAE_ASYNCRSTR_ASRST23	BIT(3)
+#define HPB_DMAE_ASYNCRSTR_ASRST22	BIT(2)
+#define HPB_DMAE_ASYNCRSTR_ASRST21	BIT(1)
+#define HPB_DMAE_ASYNCRSTR_ASRST20	BIT(0)
+
+struct hpb_dmae_slave_config {
+	unsigned int	id;
+	dma_addr_t	addr;
+	u32		dcr;
+	u32		port;
+	u32		rstr;
+	u32		mdr;
+	u32		mdm;
+	u32		flags;
+#define	HPB_DMAE_SET_ASYNC_RESET	BIT(0)
+#define	HPB_DMAE_SET_ASYNC_MODE		BIT(1)
+	u32		dma_ch;
+};
+
+#define HPB_DMAE_CHANNEL(_irq, _s_id)	\
+{					\
+	.ch_irq		= _irq,		\
+	.s_id		= _s_id,	\
+}
+
+struct hpb_dmae_channel {
+	unsigned int	ch_irq;
+	unsigned int	s_id;
+};
+
+struct hpb_dmae_pdata {
+	const struct hpb_dmae_slave_config *slaves;
+	int num_slaves;
+	const struct hpb_dmae_channel *channels;
+	int num_channels;
+	const unsigned int ts_shift[XMIT_SZ_MAX];
+	int num_hw_channels;
+};
+
+#endif