Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1398 insertions, 0 deletions

diff --git a/drivers/i2c/busses/i2c-pxa.c b/drivers/i2c/busses/i2c-pxa.c
new file mode 100644
index 000000000..c10ae4778
--- /dev/null
+++ b/drivers/i2c/busses/i2c-pxa.c
@@ -0,0 +1,1398 @@
+/*
+ *  i2c_adap_pxa.c
+ *
+ *  I2C adapter for the PXA I2C bus access.
+ *
+ *  Copyright (C) 2002 Intrinsyc Software Inc.
+ *  Copyright (C) 2004-2005 Deep Blue Solutions Ltd.
+ *
+ *  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.
+ *
+ *  History:
+ *    Apr 2002: Initial version [CS]
+ *    Jun 2002: Properly separated algo/adap [FB]
+ *    Jan 2003: Fixed several bugs concerning interrupt handling [Kai-Uwe Bloem]
+ *    Jan 2003: added limited signal handling [Kai-Uwe Bloem]
+ *    Sep 2004: Major rework to ensure efficient bus handling [RMK]
+ *    Dec 2004: Added support for PXA27x and slave device probing [Liam Girdwood]
+ *    Feb 2005: Rework slave mode handling [RMK]
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/i2c-pxa.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/platform_data/i2c-pxa.h>
+
+#include <asm/irq.h>
+
+struct pxa_reg_layout {
+	u32 ibmr;
+	u32 idbr;
+	u32 icr;
+	u32 isr;
+	u32 isar;
+	u32 ilcr;
+	u32 iwcr;
+	u32 fm;
+	u32 hs;
+};
+
+enum pxa_i2c_types {
+	REGS_PXA2XX,
+	REGS_PXA3XX,
+	REGS_CE4100,
+	REGS_PXA910,
+	REGS_A3700,
+};
+
+#define ICR_BUSMODE_FM	(1 << 16)	   /* shifted fast mode for armada-3700 */
+#define ICR_BUSMODE_HS	(1 << 17)	   /* shifted high speed mode for armada-3700 */
+
+/*
+ * I2C registers definitions
+ */
+static struct pxa_reg_layout pxa_reg_layout[] = {
+	[REGS_PXA2XX] = {
+		.ibmr =	0x00,
+		.idbr =	0x08,
+		.icr =	0x10,
+		.isr =	0x18,
+		.isar =	0x20,
+	},
+	[REGS_PXA3XX] = {
+		.ibmr =	0x00,
+		.idbr =	0x04,
+		.icr =	0x08,
+		.isr =	0x0c,
+		.isar =	0x10,
+	},
+	[REGS_CE4100] = {
+		.ibmr =	0x14,
+		.idbr =	0x0c,
+		.icr =	0x00,
+		.isr =	0x04,
+		/* no isar register */
+	},
+	[REGS_PXA910] = {
+		.ibmr = 0x00,
+		.idbr = 0x08,
+		.icr =	0x10,
+		.isr =	0x18,
+		.isar = 0x20,
+		.ilcr = 0x28,
+		.iwcr = 0x30,
+	},
+	[REGS_A3700] = {
+		.ibmr =	0x00,
+		.idbr =	0x04,
+		.icr =	0x08,
+		.isr =	0x0c,
+		.isar =	0x10,
+		.fm = ICR_BUSMODE_FM,
+		.hs = ICR_BUSMODE_HS,
+	},
+};
+
+static const struct platform_device_id i2c_pxa_id_table[] = {
+	{ "pxa2xx-i2c",		REGS_PXA2XX },
+	{ "pxa3xx-pwri2c",	REGS_PXA3XX },
+	{ "ce4100-i2c",		REGS_CE4100 },
+	{ "pxa910-i2c",		REGS_PXA910 },
+	{ "armada-3700-i2c",	REGS_A3700  },
+	{ },
+};
+MODULE_DEVICE_TABLE(platform, i2c_pxa_id_table);
+
+/*
+ * I2C bit definitions
+ */
+
+#define ICR_START	(1 << 0)	   /* start bit */
+#define ICR_STOP	(1 << 1)	   /* stop bit */
+#define ICR_ACKNAK	(1 << 2)	   /* send ACK(0) or NAK(1) */
+#define ICR_TB		(1 << 3)	   /* transfer byte bit */
+#define ICR_MA		(1 << 4)	   /* master abort */
+#define ICR_SCLE	(1 << 5)	   /* master clock enable */
+#define ICR_IUE		(1 << 6)	   /* unit enable */
+#define ICR_GCD		(1 << 7)	   /* general call disable */
+#define ICR_ITEIE	(1 << 8)	   /* enable tx interrupts */
+#define ICR_IRFIE	(1 << 9)	   /* enable rx interrupts */
+#define ICR_BEIE	(1 << 10)	   /* enable bus error ints */
+#define ICR_SSDIE	(1 << 11)	   /* slave STOP detected int enable */
+#define ICR_ALDIE	(1 << 12)	   /* enable arbitration interrupt */
+#define ICR_SADIE	(1 << 13)	   /* slave address detected int enable */
+#define ICR_UR		(1 << 14)	   /* unit reset */
+#define ICR_FM		(1 << 15)	   /* fast mode */
+#define ICR_HS		(1 << 16)	   /* High Speed mode */
+#define ICR_GPIOEN	(1 << 19)	   /* enable GPIO mode for SCL in HS */
+
+#define ISR_RWM		(1 << 0)	   /* read/write mode */
+#define ISR_ACKNAK	(1 << 1)	   /* ack/nak status */
+#define ISR_UB		(1 << 2)	   /* unit busy */
+#define ISR_IBB		(1 << 3)	   /* bus busy */
+#define ISR_SSD		(1 << 4)	   /* slave stop detected */
+#define ISR_ALD		(1 << 5)	   /* arbitration loss detected */
+#define ISR_ITE		(1 << 6)	   /* tx buffer empty */
+#define ISR_IRF		(1 << 7)	   /* rx buffer full */
+#define ISR_GCAD	(1 << 8)	   /* general call address detected */
+#define ISR_SAD		(1 << 9)	   /* slave address detected */
+#define ISR_BED		(1 << 10)	   /* bus error no ACK/NAK */
+
+/* bit field shift & mask */
+#define ILCR_SLV_SHIFT		0
+#define ILCR_SLV_MASK		(0x1FF << ILCR_SLV_SHIFT)
+#define ILCR_FLV_SHIFT		9
+#define ILCR_FLV_MASK		(0x1FF << ILCR_FLV_SHIFT)
+#define ILCR_HLVL_SHIFT		18
+#define ILCR_HLVL_MASK		(0x1FF << ILCR_HLVL_SHIFT)
+#define ILCR_HLVH_SHIFT		27
+#define ILCR_HLVH_MASK		(0x1F << ILCR_HLVH_SHIFT)
+
+#define IWCR_CNT_SHIFT		0
+#define IWCR_CNT_MASK		(0x1F << IWCR_CNT_SHIFT)
+#define IWCR_HS_CNT1_SHIFT	5
+#define IWCR_HS_CNT1_MASK	(0x1F << IWCR_HS_CNT1_SHIFT)
+#define IWCR_HS_CNT2_SHIFT	10
+#define IWCR_HS_CNT2_MASK	(0x1F << IWCR_HS_CNT2_SHIFT)
+
+struct pxa_i2c {
+	spinlock_t		lock;
+	wait_queue_head_t	wait;
+	struct i2c_msg		*msg;
+	unsigned int		msg_num;
+	unsigned int		msg_idx;
+	unsigned int		msg_ptr;
+	unsigned int		slave_addr;
+	unsigned int		req_slave_addr;
+
+	struct i2c_adapter	adap;
+	struct clk		*clk;
+#ifdef CONFIG_I2C_PXA_SLAVE
+	struct i2c_slave_client *slave;
+#endif
+
+	unsigned int		irqlogidx;
+	u32			isrlog[32];
+	u32			icrlog[32];
+
+	void __iomem		*reg_base;
+	void __iomem		*reg_ibmr;
+	void __iomem		*reg_idbr;
+	void __iomem		*reg_icr;
+	void __iomem		*reg_isr;
+	void __iomem		*reg_isar;
+	void __iomem		*reg_ilcr;
+	void __iomem		*reg_iwcr;
+
+	unsigned long		iobase;
+	unsigned long		iosize;
+
+	int			irq;
+	unsigned int		use_pio :1;
+	unsigned int		fast_mode :1;
+	unsigned int		high_mode:1;
+	unsigned char		master_code;
+	unsigned long		rate;
+	bool			highmode_enter;
+	u32			fm_mask;
+	u32			hs_mask;
+};
+
+#define _IBMR(i2c)	((i2c)->reg_ibmr)
+#define _IDBR(i2c)	((i2c)->reg_idbr)
+#define _ICR(i2c)	((i2c)->reg_icr)
+#define _ISR(i2c)	((i2c)->reg_isr)
+#define _ISAR(i2c)	((i2c)->reg_isar)
+#define _ILCR(i2c)	((i2c)->reg_ilcr)
+#define _IWCR(i2c)	((i2c)->reg_iwcr)
+
+/*
+ * I2C Slave mode address
+ */
+#define I2C_PXA_SLAVE_ADDR      0x1
+
+#ifdef DEBUG
+
+struct bits {
+	u32	mask;
+	const char *set;
+	const char *unset;
+};
+#define PXA_BIT(m, s, u)	{ .mask = m, .set = s, .unset = u }
+
+static inline void
+decode_bits(const char *prefix, const struct bits *bits, int num, u32 val)
+{
+	printk("%s %08x: ", prefix, val);
+	while (num--) {
+		const char *str = val & bits->mask ? bits->set : bits->unset;
+		if (str)
+			printk("%s ", str);
+		bits++;
+	}
+}
+
+static const struct bits isr_bits[] = {
+	PXA_BIT(ISR_RWM,	"RX",		"TX"),
+	PXA_BIT(ISR_ACKNAK,	"NAK",		"ACK"),
+	PXA_BIT(ISR_UB,		"Bsy",		"Rdy"),
+	PXA_BIT(ISR_IBB,	"BusBsy",	"BusRdy"),
+	PXA_BIT(ISR_SSD,	"SlaveStop",	NULL),
+	PXA_BIT(ISR_ALD,	"ALD",		NULL),
+	PXA_BIT(ISR_ITE,	"TxEmpty",	NULL),
+	PXA_BIT(ISR_IRF,	"RxFull",	NULL),
+	PXA_BIT(ISR_GCAD,	"GenCall",	NULL),
+	PXA_BIT(ISR_SAD,	"SlaveAddr",	NULL),
+	PXA_BIT(ISR_BED,	"BusErr",	NULL),
+};
+
+static void decode_ISR(unsigned int val)
+{
+	decode_bits(KERN_DEBUG "ISR", isr_bits, ARRAY_SIZE(isr_bits), val);
+	printk("\n");
+}
+
+static const struct bits icr_bits[] = {
+	PXA_BIT(ICR_START,  "START",	NULL),
+	PXA_BIT(ICR_STOP,   "STOP",	NULL),
+	PXA_BIT(ICR_ACKNAK, "ACKNAK",	NULL),
+	PXA_BIT(ICR_TB,     "TB",	NULL),
+	PXA_BIT(ICR_MA,     "MA",	NULL),
+	PXA_BIT(ICR_SCLE,   "SCLE",	"scle"),
+	PXA_BIT(ICR_IUE,    "IUE",	"iue"),
+	PXA_BIT(ICR_GCD,    "GCD",	NULL),
+	PXA_BIT(ICR_ITEIE,  "ITEIE",	NULL),
+	PXA_BIT(ICR_IRFIE,  "IRFIE",	NULL),
+	PXA_BIT(ICR_BEIE,   "BEIE",	NULL),
+	PXA_BIT(ICR_SSDIE,  "SSDIE",	NULL),
+	PXA_BIT(ICR_ALDIE,  "ALDIE",	NULL),
+	PXA_BIT(ICR_SADIE,  "SADIE",	NULL),
+	PXA_BIT(ICR_UR,     "UR",		"ur"),
+};
+
+#ifdef CONFIG_I2C_PXA_SLAVE
+static void decode_ICR(unsigned int val)
+{
+	decode_bits(KERN_DEBUG "ICR", icr_bits, ARRAY_SIZE(icr_bits), val);
+	printk("\n");
+}
+#endif
+
+static unsigned int i2c_debug = DEBUG;
+
+static void i2c_pxa_show_state(struct pxa_i2c *i2c, int lno, const char *fname)
+{
+	dev_dbg(&i2c->adap.dev, "state:%s:%d: ISR=%08x, ICR=%08x, IBMR=%02x\n", fname, lno,
+		readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
+}
+
+#define show_state(i2c) i2c_pxa_show_state(i2c, __LINE__, __func__)
+
+static void i2c_pxa_scream_blue_murder(struct pxa_i2c *i2c, const char *why)
+{
+	unsigned int i;
+	struct device *dev = &i2c->adap.dev;
+
+	dev_err(dev, "slave_0x%x error: %s\n",
+		i2c->req_slave_addr >> 1, why);
+	dev_err(dev, "msg_num: %d msg_idx: %d msg_ptr: %d\n",
+		i2c->msg_num, i2c->msg_idx, i2c->msg_ptr);
+	dev_err(dev, "IBMR: %08x IDBR: %08x ICR: %08x ISR: %08x\n",
+		readl(_IBMR(i2c)), readl(_IDBR(i2c)), readl(_ICR(i2c)),
+		readl(_ISR(i2c)));
+	dev_err(dev, "log:");
+	for (i = 0; i < i2c->irqlogidx; i++)
+		pr_cont(" [%03x:%05x]", i2c->isrlog[i], i2c->icrlog[i]);
+	pr_cont("\n");
+}
+
+#else /* ifdef DEBUG */
+
+#define i2c_debug	0
+
+#define show_state(i2c) do { } while (0)
+#define decode_ISR(val) do { } while (0)
+#define decode_ICR(val) do { } while (0)
+#define i2c_pxa_scream_blue_murder(i2c, why) do { } while (0)
+
+#endif /* ifdef DEBUG / else */
+
+static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret);
+static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id);
+
+static inline int i2c_pxa_is_slavemode(struct pxa_i2c *i2c)
+{
+	return !(readl(_ICR(i2c)) & ICR_SCLE);
+}
+
+static void i2c_pxa_abort(struct pxa_i2c *i2c)
+{
+	int i = 250;
+
+	if (i2c_pxa_is_slavemode(i2c)) {
+		dev_dbg(&i2c->adap.dev, "%s: called in slave mode\n", __func__);
+		return;
+	}
+
+	while ((i > 0) && (readl(_IBMR(i2c)) & 0x1) == 0) {
+		unsigned long icr = readl(_ICR(i2c));
+
+		icr &= ~ICR_START;
+		icr |= ICR_ACKNAK | ICR_STOP | ICR_TB;
+
+		writel(icr, _ICR(i2c));
+
+		show_state(i2c);
+
+		mdelay(1);
+		i --;
+	}
+
+	writel(readl(_ICR(i2c)) & ~(ICR_MA | ICR_START | ICR_STOP),
+	       _ICR(i2c));
+}
+
+static int i2c_pxa_wait_bus_not_busy(struct pxa_i2c *i2c)
+{
+	int timeout = DEF_TIMEOUT;
+
+	while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
+		if ((readl(_ISR(i2c)) & ISR_SAD) != 0)
+			timeout += 4;
+
+		msleep(2);
+		show_state(i2c);
+	}
+
+	if (timeout < 0)
+		show_state(i2c);
+
+	return timeout < 0 ? I2C_RETRY : 0;
+}
+
+static int i2c_pxa_wait_master(struct pxa_i2c *i2c)
+{
+	unsigned long timeout = jiffies + HZ*4;
+
+	while (time_before(jiffies, timeout)) {
+		if (i2c_debug > 1)
+			dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n",
+				__func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
+
+		if (readl(_ISR(i2c)) & ISR_SAD) {
+			if (i2c_debug > 0)
+				dev_dbg(&i2c->adap.dev, "%s: Slave detected\n", __func__);
+			goto out;
+		}
+
+		/* wait for unit and bus being not busy, and we also do a
+		 * quick check of the i2c lines themselves to ensure they've
+		 * gone high...
+		 */
+		if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) == 0 && readl(_IBMR(i2c)) == 3) {
+			if (i2c_debug > 0)
+				dev_dbg(&i2c->adap.dev, "%s: done\n", __func__);
+			return 1;
+		}
+
+		msleep(1);
+	}
+
+	if (i2c_debug > 0)
+		dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__);
+ out:
+	return 0;
+}
+
+static int i2c_pxa_set_master(struct pxa_i2c *i2c)
+{
+	if (i2c_debug)
+		dev_dbg(&i2c->adap.dev, "setting to bus master\n");
+
+	if ((readl(_ISR(i2c)) & (ISR_UB | ISR_IBB)) != 0) {
+		dev_dbg(&i2c->adap.dev, "%s: unit is busy\n", __func__);
+		if (!i2c_pxa_wait_master(i2c)) {
+			dev_dbg(&i2c->adap.dev, "%s: error: unit busy\n", __func__);
+			return I2C_RETRY;
+		}
+	}
+
+	writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
+	return 0;
+}
+
+#ifdef CONFIG_I2C_PXA_SLAVE
+static int i2c_pxa_wait_slave(struct pxa_i2c *i2c)
+{
+	unsigned long timeout = jiffies + HZ*1;
+
+	/* wait for stop */
+
+	show_state(i2c);
+
+	while (time_before(jiffies, timeout)) {
+		if (i2c_debug > 1)
+			dev_dbg(&i2c->adap.dev, "%s: %ld: ISR=%08x, ICR=%08x, IBMR=%02x\n",
+				__func__, (long)jiffies, readl(_ISR(i2c)), readl(_ICR(i2c)), readl(_IBMR(i2c)));
+
+		if ((readl(_ISR(i2c)) & (ISR_UB|ISR_IBB)) == 0 ||
+		    (readl(_ISR(i2c)) & ISR_SAD) != 0 ||
+		    (readl(_ICR(i2c)) & ICR_SCLE) == 0) {
+			if (i2c_debug > 1)
+				dev_dbg(&i2c->adap.dev, "%s: done\n", __func__);
+			return 1;
+		}
+
+		msleep(1);
+	}
+
+	if (i2c_debug > 0)
+		dev_dbg(&i2c->adap.dev, "%s: did not free\n", __func__);
+	return 0;
+}
+
+/*
+ * clear the hold on the bus, and take of anything else
+ * that has been configured
+ */
+static void i2c_pxa_set_slave(struct pxa_i2c *i2c, int errcode)
+{
+	show_state(i2c);
+
+	if (errcode < 0) {
+		udelay(100);   /* simple delay */
+	} else {
+		/* we need to wait for the stop condition to end */
+
+		/* if we where in stop, then clear... */
+		if (readl(_ICR(i2c)) & ICR_STOP) {
+			udelay(100);
+			writel(readl(_ICR(i2c)) & ~ICR_STOP, _ICR(i2c));
+		}
+
+		if (!i2c_pxa_wait_slave(i2c)) {
+			dev_err(&i2c->adap.dev, "%s: wait timedout\n",
+				__func__);
+			return;
+		}
+	}
+
+	writel(readl(_ICR(i2c)) & ~(ICR_STOP|ICR_ACKNAK|ICR_MA), _ICR(i2c));
+	writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
+
+	if (i2c_debug) {
+		dev_dbg(&i2c->adap.dev, "ICR now %08x, ISR %08x\n", readl(_ICR(i2c)), readl(_ISR(i2c)));
+		decode_ICR(readl(_ICR(i2c)));
+	}
+}
+#else
+#define i2c_pxa_set_slave(i2c, err)	do { } while (0)
+#endif
+
+static void i2c_pxa_reset(struct pxa_i2c *i2c)
+{
+	pr_debug("Resetting I2C Controller Unit\n");
+
+	/* abort any transfer currently under way */
+	i2c_pxa_abort(i2c);
+
+	/* reset according to 9.8 */
+	writel(ICR_UR, _ICR(i2c));
+	writel(I2C_ISR_INIT, _ISR(i2c));
+	writel(readl(_ICR(i2c)) & ~ICR_UR, _ICR(i2c));
+
+	if (i2c->reg_isar && IS_ENABLED(CONFIG_I2C_PXA_SLAVE))
+		writel(i2c->slave_addr, _ISAR(i2c));
+
+	/* set control register values */
+	writel(I2C_ICR_INIT | (i2c->fast_mode ? i2c->fm_mask : 0), _ICR(i2c));
+	writel(readl(_ICR(i2c)) | (i2c->high_mode ? i2c->hs_mask : 0), _ICR(i2c));
+
+#ifdef CONFIG_I2C_PXA_SLAVE
+	dev_info(&i2c->adap.dev, "Enabling slave mode\n");
+	writel(readl(_ICR(i2c)) | ICR_SADIE | ICR_ALDIE | ICR_SSDIE, _ICR(i2c));
+#endif
+
+	i2c_pxa_set_slave(i2c, 0);
+
+	/* enable unit */
+	writel(readl(_ICR(i2c)) | ICR_IUE, _ICR(i2c));
+	udelay(100);
+}
+
+
+#ifdef CONFIG_I2C_PXA_SLAVE
+/*
+ * PXA I2C Slave mode
+ */
+
+static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr)
+{
+	if (isr & ISR_BED) {
+		/* what should we do here? */
+	} else {
+		int ret = 0;
+
+		if (i2c->slave != NULL)
+			ret = i2c->slave->read(i2c->slave->data);
+
+		writel(ret, _IDBR(i2c));
+		writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));   /* allow next byte */
+	}
+}
+
+static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr)
+{
+	unsigned int byte = readl(_IDBR(i2c));
+
+	if (i2c->slave != NULL)
+		i2c->slave->write(i2c->slave->data, byte);
+
+	writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
+}
+
+static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
+{
+	int timeout;
+
+	if (i2c_debug > 0)
+		dev_dbg(&i2c->adap.dev, "SAD, mode is slave-%cx\n",
+		       (isr & ISR_RWM) ? 'r' : 't');
+
+	if (i2c->slave != NULL)
+		i2c->slave->event(i2c->slave->data,
+				 (isr & ISR_RWM) ? I2C_SLAVE_EVENT_START_READ : I2C_SLAVE_EVENT_START_WRITE);
+
+	/*
+	 * slave could interrupt in the middle of us generating a
+	 * start condition... if this happens, we'd better back off
+	 * and stop holding the poor thing up
+	 */
+	writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c));
+	writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
+
+	timeout = 0x10000;
+
+	while (1) {
+		if ((readl(_IBMR(i2c)) & 2) == 2)
+			break;
+
+		timeout--;
+
+		if (timeout <= 0) {
+			dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n");
+			break;
+		}
+	}
+
+	writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
+}
+
+static void i2c_pxa_slave_stop(struct pxa_i2c *i2c)
+{
+	if (i2c_debug > 2)
+		dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop)\n");
+
+	if (i2c->slave != NULL)
+		i2c->slave->event(i2c->slave->data, I2C_SLAVE_EVENT_STOP);
+
+	if (i2c_debug > 2)
+		dev_dbg(&i2c->adap.dev, "ISR: SSD (Slave Stop) acked\n");
+
+	/*
+	 * If we have a master-mode message waiting,
+	 * kick it off now that the slave has completed.
+	 */
+	if (i2c->msg)
+		i2c_pxa_master_complete(i2c, I2C_RETRY);
+}
+#else
+static void i2c_pxa_slave_txempty(struct pxa_i2c *i2c, u32 isr)
+{
+	if (isr & ISR_BED) {
+		/* what should we do here? */
+	} else {
+		writel(0, _IDBR(i2c));
+		writel(readl(_ICR(i2c)) | ICR_TB, _ICR(i2c));
+	}
+}
+
+static void i2c_pxa_slave_rxfull(struct pxa_i2c *i2c, u32 isr)
+{
+	writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c));
+}
+
+static void i2c_pxa_slave_start(struct pxa_i2c *i2c, u32 isr)
+{
+	int timeout;
+
+	/*
+	 * slave could interrupt in the middle of us generating a
+	 * start condition... if this happens, we'd better back off
+	 * and stop holding the poor thing up
+	 */
+	writel(readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP), _ICR(i2c));
+	writel(readl(_ICR(i2c)) | ICR_TB | ICR_ACKNAK, _ICR(i2c));
+
+	timeout = 0x10000;
+
+	while (1) {
+		if ((readl(_IBMR(i2c)) & 2) == 2)
+			break;
+
+		timeout--;
+
+		if (timeout <= 0) {
+			dev_err(&i2c->adap.dev, "timeout waiting for SCL high\n");
+			break;
+		}
+	}
+
+	writel(readl(_ICR(i2c)) & ~ICR_SCLE, _ICR(i2c));
+}
+
+static void i2c_pxa_slave_stop(struct pxa_i2c *i2c)
+{
+	if (i2c->msg)
+		i2c_pxa_master_complete(i2c, I2C_RETRY);
+}
+#endif
+
+/*
+ * PXA I2C Master mode
+ */
+
+static inline unsigned int i2c_pxa_addr_byte(struct i2c_msg *msg)
+{
+	unsigned int addr = (msg->addr & 0x7f) << 1;
+
+	if (msg->flags & I2C_M_RD)
+		addr |= 1;
+
+	return addr;
+}
+
+static inline void i2c_pxa_start_message(struct pxa_i2c *i2c)
+{
+	u32 icr;
+
+	/*
+	 * Step 1: target slave address into IDBR
+	 */
+	writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
+	i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
+
+	/*
+	 * Step 2: initiate the write.
+	 */
+	icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE);
+	writel(icr | ICR_START | ICR_TB, _ICR(i2c));
+}
+
+static inline void i2c_pxa_stop_message(struct pxa_i2c *i2c)
+{
+	u32 icr;
+
+	/* Clear the START, STOP, ACK, TB and MA flags */
+	icr = readl(_ICR(i2c));
+	icr &= ~(ICR_START | ICR_STOP | ICR_ACKNAK | ICR_TB | ICR_MA);
+	writel(icr, _ICR(i2c));
+}
+
+static int i2c_pxa_pio_set_master(struct pxa_i2c *i2c)
+{
+	/* make timeout the same as for interrupt based functions */
+	long timeout = 2 * DEF_TIMEOUT;
+
+	/*
+	 * Wait for the bus to become free.
+	 */
+	while (timeout-- && readl(_ISR(i2c)) & (ISR_IBB | ISR_UB)) {
+		udelay(1000);
+		show_state(i2c);
+	}
+
+	if (timeout < 0) {
+		show_state(i2c);
+		dev_err(&i2c->adap.dev,
+			"i2c_pxa: timeout waiting for bus free\n");
+		return I2C_RETRY;
+	}
+
+	/*
+	 * Set master mode.
+	 */
+	writel(readl(_ICR(i2c)) | ICR_SCLE, _ICR(i2c));
+
+	return 0;
+}
+
+/*
+ * PXA I2C send master code
+ * 1. Load master code to IDBR and send it.
+ *    Note for HS mode, set ICR [GPIOEN].
+ * 2. Wait until win arbitration.
+ */
+static int i2c_pxa_send_mastercode(struct pxa_i2c *i2c)
+{
+	u32 icr;
+	long timeout;
+
+	spin_lock_irq(&i2c->lock);
+	i2c->highmode_enter = true;
+	writel(i2c->master_code, _IDBR(i2c));
+
+	icr = readl(_ICR(i2c)) & ~(ICR_STOP | ICR_ALDIE);
+	icr |= ICR_GPIOEN | ICR_START | ICR_TB | ICR_ITEIE;
+	writel(icr, _ICR(i2c));
+
+	spin_unlock_irq(&i2c->lock);
+	timeout = wait_event_timeout(i2c->wait,
+			i2c->highmode_enter == false, HZ * 1);
+
+	i2c->highmode_enter = false;
+
+	return (timeout == 0) ? I2C_RETRY : 0;
+}
+
+static int i2c_pxa_do_pio_xfer(struct pxa_i2c *i2c,
+			       struct i2c_msg *msg, int num)
+{
+	unsigned long timeout = 500000; /* 5 seconds */
+	int ret = 0;
+
+	ret = i2c_pxa_pio_set_master(i2c);
+	if (ret)
+		goto out;
+
+	i2c->msg = msg;
+	i2c->msg_num = num;
+	i2c->msg_idx = 0;
+	i2c->msg_ptr = 0;
+	i2c->irqlogidx = 0;
+
+	i2c_pxa_start_message(i2c);
+
+	while (i2c->msg_num > 0 && --timeout) {
+		i2c_pxa_handler(0, i2c);
+		udelay(10);
+	}
+
+	i2c_pxa_stop_message(i2c);
+
+	/*
+	 * We place the return code in i2c->msg_idx.
+	 */
+	ret = i2c->msg_idx;
+
+out:
+	if (timeout == 0) {
+		i2c_pxa_scream_blue_murder(i2c, "timeout");
+		ret = I2C_RETRY;
+	}
+
+	return ret;
+}
+
+/*
+ * We are protected by the adapter bus mutex.
+ */
+static int i2c_pxa_do_xfer(struct pxa_i2c *i2c, struct i2c_msg *msg, int num)
+{
+	long timeout;
+	int ret;
+
+	/*
+	 * Wait for the bus to become free.
+	 */
+	ret = i2c_pxa_wait_bus_not_busy(i2c);
+	if (ret) {
+		dev_err(&i2c->adap.dev, "i2c_pxa: timeout waiting for bus free\n");
+		goto out;
+	}
+
+	/*
+	 * Set master mode.
+	 */
+	ret = i2c_pxa_set_master(i2c);
+	if (ret) {
+		dev_err(&i2c->adap.dev, "i2c_pxa_set_master: error %d\n", ret);
+		goto out;
+	}
+
+	if (i2c->high_mode) {
+		ret = i2c_pxa_send_mastercode(i2c);
+		if (ret) {
+			dev_err(&i2c->adap.dev, "i2c_pxa_send_mastercode timeout\n");
+			goto out;
+			}
+	}
+
+	spin_lock_irq(&i2c->lock);
+
+	i2c->msg = msg;
+	i2c->msg_num = num;
+	i2c->msg_idx = 0;
+	i2c->msg_ptr = 0;
+	i2c->irqlogidx = 0;
+
+	i2c_pxa_start_message(i2c);
+
+	spin_unlock_irq(&i2c->lock);
+
+	/*
+	 * The rest of the processing occurs in the interrupt handler.
+	 */
+	timeout = wait_event_timeout(i2c->wait, i2c->msg_num == 0, HZ * 5);
+	i2c_pxa_stop_message(i2c);
+
+	/*
+	 * We place the return code in i2c->msg_idx.
+	 */
+	ret = i2c->msg_idx;
+
+	if (!timeout && i2c->msg_num) {
+		i2c_pxa_scream_blue_murder(i2c, "timeout");
+		ret = I2C_RETRY;
+	}
+
+ out:
+	return ret;
+}
+
+static int i2c_pxa_pio_xfer(struct i2c_adapter *adap,
+			    struct i2c_msg msgs[], int num)
+{
+	struct pxa_i2c *i2c = adap->algo_data;
+	int ret, i;
+
+	/* If the I2C controller is disabled we need to reset it
+	  (probably due to a suspend/resume destroying state). We do
+	  this here as we can then avoid worrying about resuming the
+	  controller before its users. */
+	if (!(readl(_ICR(i2c)) & ICR_IUE))
+		i2c_pxa_reset(i2c);
+
+	for (i = adap->retries; i >= 0; i--) {
+		ret = i2c_pxa_do_pio_xfer(i2c, msgs, num);
+		if (ret != I2C_RETRY)
+			goto out;
+
+		if (i2c_debug)
+			dev_dbg(&adap->dev, "Retrying transmission\n");
+		udelay(100);
+	}
+	i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
+	ret = -EREMOTEIO;
+ out:
+	i2c_pxa_set_slave(i2c, ret);
+	return ret;
+}
+
+/*
+ * i2c_pxa_master_complete - complete the message and wake up.
+ */
+static void i2c_pxa_master_complete(struct pxa_i2c *i2c, int ret)
+{
+	i2c->msg_ptr = 0;
+	i2c->msg = NULL;
+	i2c->msg_idx ++;
+	i2c->msg_num = 0;
+	if (ret)
+		i2c->msg_idx = ret;
+	if (!i2c->use_pio)
+		wake_up(&i2c->wait);
+}
+
+static void i2c_pxa_irq_txempty(struct pxa_i2c *i2c, u32 isr)
+{
+	u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB);
+
+ again:
+	/*
+	 * If ISR_ALD is set, we lost arbitration.
+	 */
+	if (isr & ISR_ALD) {
+		/*
+		 * Do we need to do anything here?  The PXA docs
+		 * are vague about what happens.
+		 */
+		i2c_pxa_scream_blue_murder(i2c, "ALD set");
+
+		/*
+		 * We ignore this error.  We seem to see spurious ALDs
+		 * for seemingly no reason.  If we handle them as I think
+		 * they should, we end up causing an I2C error, which
+		 * is painful for some systems.
+		 */
+		return; /* ignore */
+	}
+
+	if ((isr & ISR_BED) &&
+		(!((i2c->msg->flags & I2C_M_IGNORE_NAK) &&
+			(isr & ISR_ACKNAK)))) {
+		int ret = BUS_ERROR;
+
+		/*
+		 * I2C bus error - either the device NAK'd us, or
+		 * something more serious happened.  If we were NAK'd
+		 * on the initial address phase, we can retry.
+		 */
+		if (isr & ISR_ACKNAK) {
+			if (i2c->msg_ptr == 0 && i2c->msg_idx == 0)
+				ret = I2C_RETRY;
+			else
+				ret = XFER_NAKED;
+		}
+		i2c_pxa_master_complete(i2c, ret);
+	} else if (isr & ISR_RWM) {
+		/*
+		 * Read mode.  We have just sent the address byte, and
+		 * now we must initiate the transfer.
+		 */
+		if (i2c->msg_ptr == i2c->msg->len - 1 &&
+		    i2c->msg_idx == i2c->msg_num - 1)
+			icr |= ICR_STOP | ICR_ACKNAK;
+
+		icr |= ICR_ALDIE | ICR_TB;
+	} else if (i2c->msg_ptr < i2c->msg->len) {
+		/*
+		 * Write mode.  Write the next data byte.
+		 */
+		writel(i2c->msg->buf[i2c->msg_ptr++], _IDBR(i2c));
+
+		icr |= ICR_ALDIE | ICR_TB;
+
+		/*
+		 * If this is the last byte of the last message or last byte
+		 * of any message with I2C_M_STOP (e.g. SCCB), send a STOP.
+		 */
+		if ((i2c->msg_ptr == i2c->msg->len) &&
+			((i2c->msg->flags & I2C_M_STOP) ||
+			(i2c->msg_idx == i2c->msg_num - 1)))
+				icr |= ICR_STOP;
+
+	} else if (i2c->msg_idx < i2c->msg_num - 1) {
+		/*
+		 * Next segment of the message.
+		 */
+		i2c->msg_ptr = 0;
+		i2c->msg_idx ++;
+		i2c->msg++;
+
+		/*
+		 * If we aren't doing a repeated start and address,
+		 * go back and try to send the next byte.  Note that
+		 * we do not support switching the R/W direction here.
+		 */
+		if (i2c->msg->flags & I2C_M_NOSTART)
+			goto again;
+
+		/*
+		 * Write the next address.
+		 */
+		writel(i2c_pxa_addr_byte(i2c->msg), _IDBR(i2c));
+		i2c->req_slave_addr = i2c_pxa_addr_byte(i2c->msg);
+
+		/*
+		 * And trigger a repeated start, and send the byte.
+		 */
+		icr &= ~ICR_ALDIE;
+		icr |= ICR_START | ICR_TB;
+	} else {
+		if (i2c->msg->len == 0) {
+			/*
+			 * Device probes have a message length of zero
+			 * and need the bus to be reset before it can
+			 * be used again.
+			 */
+			i2c_pxa_reset(i2c);
+		}
+		i2c_pxa_master_complete(i2c, 0);
+	}
+
+	i2c->icrlog[i2c->irqlogidx-1] = icr;
+
+	writel(icr, _ICR(i2c));
+	show_state(i2c);
+}
+
+static void i2c_pxa_irq_rxfull(struct pxa_i2c *i2c, u32 isr)
+{
+	u32 icr = readl(_ICR(i2c)) & ~(ICR_START|ICR_STOP|ICR_ACKNAK|ICR_TB);
+
+	/*
+	 * Read the byte.
+	 */
+	i2c->msg->buf[i2c->msg_ptr++] = readl(_IDBR(i2c));
+
+	if (i2c->msg_ptr < i2c->msg->len) {
+		/*
+		 * If this is the last byte of the last
+		 * message, send a STOP.
+		 */
+		if (i2c->msg_ptr == i2c->msg->len - 1)
+			icr |= ICR_STOP | ICR_ACKNAK;
+
+		icr |= ICR_ALDIE | ICR_TB;
+	} else {
+		i2c_pxa_master_complete(i2c, 0);
+	}
+
+	i2c->icrlog[i2c->irqlogidx-1] = icr;
+
+	writel(icr, _ICR(i2c));
+}
+
+#define VALID_INT_SOURCE	(ISR_SSD | ISR_ALD | ISR_ITE | ISR_IRF | \
+				ISR_SAD | ISR_BED)
+static irqreturn_t i2c_pxa_handler(int this_irq, void *dev_id)
+{
+	struct pxa_i2c *i2c = dev_id;
+	u32 isr = readl(_ISR(i2c));
+
+	if (!(isr & VALID_INT_SOURCE))
+		return IRQ_NONE;
+
+	if (i2c_debug > 2 && 0) {
+		dev_dbg(&i2c->adap.dev, "%s: ISR=%08x, ICR=%08x, IBMR=%02x\n",
+			__func__, isr, readl(_ICR(i2c)), readl(_IBMR(i2c)));
+		decode_ISR(isr);
+	}
+
+	if (i2c->irqlogidx < ARRAY_SIZE(i2c->isrlog))
+		i2c->isrlog[i2c->irqlogidx++] = isr;
+
+	show_state(i2c);
+
+	/*
+	 * Always clear all pending IRQs.
+	 */
+	writel(isr & VALID_INT_SOURCE, _ISR(i2c));
+
+	if (isr & ISR_SAD)
+		i2c_pxa_slave_start(i2c, isr);
+	if (isr & ISR_SSD)
+		i2c_pxa_slave_stop(i2c);
+
+	if (i2c_pxa_is_slavemode(i2c)) {
+		if (isr & ISR_ITE)
+			i2c_pxa_slave_txempty(i2c, isr);
+		if (isr & ISR_IRF)
+			i2c_pxa_slave_rxfull(i2c, isr);
+	} else if (i2c->msg && (!i2c->highmode_enter)) {
+		if (isr & ISR_ITE)
+			i2c_pxa_irq_txempty(i2c, isr);
+		if (isr & ISR_IRF)
+			i2c_pxa_irq_rxfull(i2c, isr);
+	} else if ((isr & ISR_ITE) && i2c->highmode_enter) {
+		i2c->highmode_enter = false;
+		wake_up(&i2c->wait);
+	} else {
+		i2c_pxa_scream_blue_murder(i2c, "spurious irq");
+	}
+
+	return IRQ_HANDLED;
+}
+
+
+static int i2c_pxa_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
+{
+	struct pxa_i2c *i2c = adap->algo_data;
+	int ret, i;
+
+	for (i = adap->retries; i >= 0; i--) {
+		ret = i2c_pxa_do_xfer(i2c, msgs, num);
+		if (ret != I2C_RETRY)
+			goto out;
+
+		if (i2c_debug)
+			dev_dbg(&adap->dev, "Retrying transmission\n");
+		udelay(100);
+	}
+	i2c_pxa_scream_blue_murder(i2c, "exhausted retries");
+	ret = -EREMOTEIO;
+ out:
+	i2c_pxa_set_slave(i2c, ret);
+	return ret;
+}
+
+static u32 i2c_pxa_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL |
+		I2C_FUNC_PROTOCOL_MANGLING | I2C_FUNC_NOSTART;
+}
+
+static const struct i2c_algorithm i2c_pxa_algorithm = {
+	.master_xfer	= i2c_pxa_xfer,
+	.functionality	= i2c_pxa_functionality,
+};
+
+static const struct i2c_algorithm i2c_pxa_pio_algorithm = {
+	.master_xfer	= i2c_pxa_pio_xfer,
+	.functionality	= i2c_pxa_functionality,
+};
+
+static const struct of_device_id i2c_pxa_dt_ids[] = {
+	{ .compatible = "mrvl,pxa-i2c", .data = (void *)REGS_PXA2XX },
+	{ .compatible = "mrvl,pwri2c", .data = (void *)REGS_PXA3XX },
+	{ .compatible = "mrvl,mmp-twsi", .data = (void *)REGS_PXA910 },
+	{ .compatible = "marvell,armada-3700-i2c", .data = (void *)REGS_A3700 },
+	{}
+};
+MODULE_DEVICE_TABLE(of, i2c_pxa_dt_ids);
+
+static int i2c_pxa_probe_dt(struct platform_device *pdev, struct pxa_i2c *i2c,
+			    enum pxa_i2c_types *i2c_types)
+{
+	struct device_node *np = pdev->dev.of_node;
+	const struct of_device_id *of_id =
+			of_match_device(i2c_pxa_dt_ids, &pdev->dev);
+
+	if (!of_id)
+		return 1;
+
+	/* For device tree we always use the dynamic or alias-assigned ID */
+	i2c->adap.nr = -1;
+
+	if (of_get_property(np, "mrvl,i2c-polling", NULL))
+		i2c->use_pio = 1;
+	if (of_get_property(np, "mrvl,i2c-fast-mode", NULL))
+		i2c->fast_mode = 1;
+
+	*i2c_types = (enum pxa_i2c_types)(of_id->data);
+
+	return 0;
+}
+
+static int i2c_pxa_probe_pdata(struct platform_device *pdev,
+			       struct pxa_i2c *i2c,
+			       enum pxa_i2c_types *i2c_types)
+{
+	struct i2c_pxa_platform_data *plat = dev_get_platdata(&pdev->dev);
+	const struct platform_device_id *id = platform_get_device_id(pdev);
+
+	*i2c_types = id->driver_data;
+	if (plat) {
+		i2c->use_pio = plat->use_pio;
+		i2c->fast_mode = plat->fast_mode;
+		i2c->high_mode = plat->high_mode;
+		i2c->master_code = plat->master_code;
+		if (!i2c->master_code)
+			i2c->master_code = 0xe;
+		i2c->rate = plat->rate;
+	}
+	return 0;
+}
+
+static int i2c_pxa_probe(struct platform_device *dev)
+{
+	struct i2c_pxa_platform_data *plat = dev_get_platdata(&dev->dev);
+	enum pxa_i2c_types i2c_type;
+	struct pxa_i2c *i2c;
+	struct resource *res = NULL;
+	int ret, irq;
+
+	i2c = devm_kzalloc(&dev->dev, sizeof(struct pxa_i2c), GFP_KERNEL);
+	if (!i2c)
+		return -ENOMEM;
+
+	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+	i2c->reg_base = devm_ioremap_resource(&dev->dev, res);
+	if (IS_ERR(i2c->reg_base))
+		return PTR_ERR(i2c->reg_base);
+
+	irq = platform_get_irq(dev, 0);
+	if (irq < 0) {
+		dev_err(&dev->dev, "no irq resource: %d\n", irq);
+		return irq;
+	}
+
+	/* Default adapter num to device id; i2c_pxa_probe_dt can override. */
+	i2c->adap.nr = dev->id;
+
+	ret = i2c_pxa_probe_dt(dev, i2c, &i2c_type);
+	if (ret > 0)
+		ret = i2c_pxa_probe_pdata(dev, i2c, &i2c_type);
+	if (ret < 0)
+		return ret;
+
+	i2c->adap.owner   = THIS_MODULE;
+	i2c->adap.retries = 5;
+
+	spin_lock_init(&i2c->lock);
+	init_waitqueue_head(&i2c->wait);
+
+	strlcpy(i2c->adap.name, "pxa_i2c-i2c", sizeof(i2c->adap.name));
+
+	i2c->clk = devm_clk_get(&dev->dev, NULL);
+	if (IS_ERR(i2c->clk)) {
+		dev_err(&dev->dev, "failed to get the clk: %ld\n", PTR_ERR(i2c->clk));
+		return PTR_ERR(i2c->clk);
+	}
+
+	i2c->reg_ibmr = i2c->reg_base + pxa_reg_layout[i2c_type].ibmr;
+	i2c->reg_idbr = i2c->reg_base + pxa_reg_layout[i2c_type].idbr;
+	i2c->reg_icr = i2c->reg_base + pxa_reg_layout[i2c_type].icr;
+	i2c->reg_isr = i2c->reg_base + pxa_reg_layout[i2c_type].isr;
+	i2c->fm_mask = pxa_reg_layout[i2c_type].fm ? : ICR_FM;
+	i2c->hs_mask = pxa_reg_layout[i2c_type].hs ? : ICR_HS;
+
+	if (i2c_type != REGS_CE4100)
+		i2c->reg_isar = i2c->reg_base + pxa_reg_layout[i2c_type].isar;
+
+	if (i2c_type == REGS_PXA910) {
+		i2c->reg_ilcr = i2c->reg_base + pxa_reg_layout[i2c_type].ilcr;
+		i2c->reg_iwcr = i2c->reg_base + pxa_reg_layout[i2c_type].iwcr;
+	}
+
+	i2c->iobase = res->start;
+	i2c->iosize = resource_size(res);
+
+	i2c->irq = irq;
+
+	i2c->slave_addr = I2C_PXA_SLAVE_ADDR;
+	i2c->highmode_enter = false;
+
+	if (plat) {
+#ifdef CONFIG_I2C_PXA_SLAVE
+		i2c->slave_addr = plat->slave_addr;
+		i2c->slave = plat->slave;
+#endif
+		i2c->adap.class = plat->class;
+	}
+
+	if (i2c->high_mode) {
+		if (i2c->rate) {
+			clk_set_rate(i2c->clk, i2c->rate);
+			pr_info("i2c: <%s> set rate to %ld\n",
+				i2c->adap.name, clk_get_rate(i2c->clk));
+		} else
+			pr_warn("i2c: <%s> clock rate not set\n",
+				i2c->adap.name);
+	}
+
+	clk_prepare_enable(i2c->clk);
+
+	if (i2c->use_pio) {
+		i2c->adap.algo = &i2c_pxa_pio_algorithm;
+	} else {
+		i2c->adap.algo = &i2c_pxa_algorithm;
+		ret = devm_request_irq(&dev->dev, irq, i2c_pxa_handler,
+				IRQF_SHARED | IRQF_NO_SUSPEND,
+				dev_name(&dev->dev), i2c);
+		if (ret) {
+			dev_err(&dev->dev, "failed to request irq: %d\n", ret);
+			goto ereqirq;
+		}
+	}
+
+	i2c_pxa_reset(i2c);
+
+	i2c->adap.algo_data = i2c;
+	i2c->adap.dev.parent = &dev->dev;
+#ifdef CONFIG_OF
+	i2c->adap.dev.of_node = dev->dev.of_node;
+#endif
+
+	ret = i2c_add_numbered_adapter(&i2c->adap);
+	if (ret < 0)
+		goto ereqirq;
+
+	platform_set_drvdata(dev, i2c);
+
+#ifdef CONFIG_I2C_PXA_SLAVE
+	dev_info(&i2c->adap.dev, " PXA I2C adapter, slave address %d\n",
+		i2c->slave_addr);
+#else
+	dev_info(&i2c->adap.dev, " PXA I2C adapter\n");
+#endif
+	return 0;
+
+ereqirq:
+	clk_disable_unprepare(i2c->clk);
+	return ret;
+}
+
+static int i2c_pxa_remove(struct platform_device *dev)
+{
+	struct pxa_i2c *i2c = platform_get_drvdata(dev);
+
+	i2c_del_adapter(&i2c->adap);
+
+	clk_disable_unprepare(i2c->clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static int i2c_pxa_suspend_noirq(struct device *dev)
+{
+	struct pxa_i2c *i2c = dev_get_drvdata(dev);
+
+	clk_disable(i2c->clk);
+
+	return 0;
+}
+
+static int i2c_pxa_resume_noirq(struct device *dev)
+{
+	struct pxa_i2c *i2c = dev_get_drvdata(dev);
+
+	clk_enable(i2c->clk);
+	i2c_pxa_reset(i2c);
+
+	return 0;
+}
+
+static const struct dev_pm_ops i2c_pxa_dev_pm_ops = {
+	.suspend_noirq = i2c_pxa_suspend_noirq,
+	.resume_noirq = i2c_pxa_resume_noirq,
+};
+
+#define I2C_PXA_DEV_PM_OPS (&i2c_pxa_dev_pm_ops)
+#else
+#define I2C_PXA_DEV_PM_OPS NULL
+#endif
+
+static struct platform_driver i2c_pxa_driver = {
+	.probe		= i2c_pxa_probe,
+	.remove		= i2c_pxa_remove,
+	.driver		= {
+		.name	= "pxa2xx-i2c",
+		.pm	= I2C_PXA_DEV_PM_OPS,
+		.of_match_table = i2c_pxa_dt_ids,
+	},
+	.id_table	= i2c_pxa_id_table,
+};
+
+static int __init i2c_adap_pxa_init(void)
+{
+	return platform_driver_register(&i2c_pxa_driver);
+}
+
+static void __exit i2c_adap_pxa_exit(void)
+{
+	platform_driver_unregister(&i2c_pxa_driver);
+}
+
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:pxa2xx-i2c");
+
+subsys_initcall(i2c_adap_pxa_init);
+module_exit(i2c_adap_pxa_exit);