Merge branch 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c changes from Wolfram Sang: - new drivers for exynos5, bcm kona, and st micro - bigger overhauls for drivers mxs and rcar - typical driver bugfixes, cleanups, improvements - got rid of the superfluous 'driver' member in i2c_client struct This touches a few drivers in other subsystems. All acked. * 'i2c/for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (38 commits) i2c: bcm-kona: fix error return code in bcm_kona_i2c_probe() i2c: i2c-eg20t: do not print error message in syslog if no ACK received i2c: bcm-kona: Introduce Broadcom I2C Driver i2c: cbus-gpio: Fix device tree binding i2c: wmt: add missing clk_disable_unprepare() on error i2c: designware: add new ACPI IDs i2c: i801: Add Device IDs for Intel Wildcat Point-LP PCH i2c: exynos5: Remove incorrect clk_disable_unprepare i2c: i2c-st: Add ST I2C controller i2c: exynos5: add High Speed I2C controller driver i2c: rcar: fixup rcar type naming i2c: scmi: remove some bogus NULL checks i2c: sh_mobile & rcar: Enable the driver on all ARM platforms i2c: sh_mobile: Convert to clk_prepare/unprepare i2c: mux: gpio: use reg value for i2c_add_mux_adapter i2c: mux: gpio: use gpio_set_value_cansleep() i2c: Include linux/of.h header i2c: mxs: Fix PIO mode on i.MX23 i2c: mxs: Rework the PIO mode operation i2c: mxs: distinguish i.MX23 and i.MX28 based I2C controller ...
author: Linus Torvalds 2013-11-18 15:50:07 -0800
committer: Linus Torvalds 2013-11-18 15:50:07 -0800
commit: 13509c3a9d20a9df93dc9b944e8bd20fe1b454a7 (patch)
tree: d7a97d1d10e88bcb93852cb0143a000710e9e246 /drivers/i2c
parent: 1ea406c0e08c717241275064046d29b5bac1b1db (diff)
parent: cfff1f4a9367bfe0d88413e8807f8369e9564729 (diff)
27 files changed, 2918 insertions, 194 deletions
diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index cdcbd8368ed3..3b26129f6055 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -109,6 +109,7 @@ config I2C_I801
 	    Avoton (SOC)
 	    Wellsburg (PCH)
 	    Coleto Creek (PCH)
+	    Wildcat Point-LP (PCH)
 
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-i801.
@@ -345,6 +346,16 @@ config I2C_BCM2835
 	  This support is also available as a module.  If so, the module
 	  will be called i2c-bcm2835.
 
+config I2C_BCM_KONA
+	tristate "BCM Kona I2C adapter"
+	depends on ARCH_BCM_MOBILE
+	default y
+	help
+	  If you say yes to this option, support will be included for the
+	  I2C interface on the Broadcom Kona family of processors.
+
+	  If you do not need KONA I2C inteface, say N.
+
 config I2C_BLACKFIN_TWI
 	tristate "Blackfin TWI I2C support"
 	depends on BLACKFIN
@@ -436,6 +447,13 @@ config I2C_EG20T
 	  ML7213/ML7223/ML7831 is companion chip for Intel Atom E6xx series.
 	  ML7213/ML7223/ML7831 is completely compatible for Intel EG20T PCH.
 
+config I2C_EXYNOS5
+	tristate "Exynos5 high-speed I2C driver"
+	depends on ARCH_EXYNOS5 && OF
+	help
+	  Say Y here to include support for high-speed I2C controller in the
+	  Exynos5 based Samsung SoCs.
+
 config I2C_GPIO
 	tristate "GPIO-based bitbanging I2C"
 	depends on GPIOLIB
@@ -665,7 +683,7 @@ config I2C_SH7760
 
 config I2C_SH_MOBILE
 	tristate "SuperH Mobile I2C Controller"
-	depends on SUPERH || ARCH_SHMOBILE
+	depends on SUPERH || ARM || COMPILE_TEST
 	help
 	  If you say yes to this option, support will be included for the
 	  built-in I2C interface on the Renesas SH-Mobile processor.
@@ -695,6 +713,16 @@ config I2C_SIRF
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-sirf.
 
+config I2C_ST
+	tristate "STMicroelectronics SSC I2C support"
+	depends on ARCH_STI
+	help
+	  Enable this option to add support for STMicroelectronics SoCs
+	  hardware SSC (Synchronous Serial Controller) as an I2C controller.
+
+	  This driver can also be built as module. If so, the module
+	  will be called i2c-st.
+
 config I2C_STU300
 	tristate "ST Microelectronics DDC I2C interface"
 	depends on MACH_U300
@@ -768,7 +796,7 @@ config I2C_XLR
 
 config I2C_RCAR
 	tristate "Renesas R-Car I2C Controller"
-	depends on ARCH_SHMOBILE && I2C
+	depends on ARM || COMPILE_TEST
 	help
 	  If you say yes to this option, support will be included for the
 	  R-Car I2C controller.
diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index d00997f3eb3b..c73eb0ea788e 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -42,6 +42,7 @@ i2c-designware-platform-objs := i2c-designware-platdrv.o
 obj-$(CONFIG_I2C_DESIGNWARE_PCI)	+= i2c-designware-pci.o
 i2c-designware-pci-objs := i2c-designware-pcidrv.o
 obj-$(CONFIG_I2C_EG20T)		+= i2c-eg20t.o
+obj-$(CONFIG_I2C_EXYNOS5)	+= i2c-exynos5.o
 obj-$(CONFIG_I2C_GPIO)		+= i2c-gpio.o
 obj-$(CONFIG_I2C_HIGHLANDER)	+= i2c-highlander.o
 obj-$(CONFIG_I2C_IBM_IIC)	+= i2c-ibm_iic.o
@@ -68,6 +69,7 @@ obj-$(CONFIG_I2C_SH7760)	+= i2c-sh7760.o
 obj-$(CONFIG_I2C_SH_MOBILE)	+= i2c-sh_mobile.o
 obj-$(CONFIG_I2C_SIMTEC)	+= i2c-simtec.o
 obj-$(CONFIG_I2C_SIRF)		+= i2c-sirf.o
+obj-$(CONFIG_I2C_ST)		+= i2c-st.o
 obj-$(CONFIG_I2C_STU300)	+= i2c-stu300.o
 obj-$(CONFIG_I2C_TEGRA)		+= i2c-tegra.o
 obj-$(CONFIG_I2C_VERSATILE)	+= i2c-versatile.o
@@ -87,6 +89,7 @@ obj-$(CONFIG_I2C_VIPERBOARD)	+= i2c-viperboard.o
 
 # Other I2C/SMBus bus drivers
 obj-$(CONFIG_I2C_ACORN)		+= i2c-acorn.o
+obj-$(CONFIG_I2C_BCM_KONA)	+= i2c-bcm-kona.o
 obj-$(CONFIG_I2C_ELEKTOR)	+= i2c-elektor.o
 obj-$(CONFIG_I2C_PCA_ISA)	+= i2c-pca-isa.o
 obj-$(CONFIG_I2C_SIBYTE)	+= i2c-sibyte.o
diff --git a/drivers/i2c/busses/i2c-bcm-kona.c b/drivers/i2c/busses/i2c-bcm-kona.c
new file mode 100644
index 000000000000..036cf03aeb61
--- /dev/null
+++ b/drivers/i2c/busses/i2c-bcm-kona.c
@@ -0,0 +1,909 @@
+/*
+ * Copyright (C) 2013 Broadcom Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+
+/* Hardware register offsets and field defintions */
+#define CS_OFFSET				0x00000020
+#define CS_ACK_SHIFT				3
+#define CS_ACK_MASK				0x00000008
+#define CS_ACK_CMD_GEN_START			0x00000000
+#define CS_ACK_CMD_GEN_RESTART			0x00000001
+#define CS_CMD_SHIFT				1
+#define CS_CMD_CMD_NO_ACTION			0x00000000
+#define CS_CMD_CMD_START_RESTART		0x00000001
+#define CS_CMD_CMD_STOP				0x00000002
+#define CS_EN_SHIFT				0
+#define CS_EN_CMD_ENABLE_BSC			0x00000001
+
+#define TIM_OFFSET				0x00000024
+#define TIM_PRESCALE_SHIFT			6
+#define TIM_P_SHIFT				3
+#define TIM_NO_DIV_SHIFT			2
+#define TIM_DIV_SHIFT				0
+
+#define DAT_OFFSET				0x00000028
+
+#define TOUT_OFFSET				0x0000002c
+
+#define TXFCR_OFFSET				0x0000003c
+#define TXFCR_FIFO_FLUSH_MASK			0x00000080
+#define TXFCR_FIFO_EN_MASK			0x00000040
+
+#define IER_OFFSET				0x00000044
+#define IER_READ_COMPLETE_INT_MASK		0x00000010
+#define IER_I2C_INT_EN_MASK			0x00000008
+#define IER_FIFO_INT_EN_MASK			0x00000002
+#define IER_NOACK_EN_MASK			0x00000001
+
+#define ISR_OFFSET				0x00000048
+#define ISR_RESERVED_MASK			0xffffff60
+#define ISR_CMDBUSY_MASK			0x00000080
+#define ISR_READ_COMPLETE_MASK			0x00000010
+#define ISR_SES_DONE_MASK			0x00000008
+#define ISR_ERR_MASK				0x00000004
+#define ISR_TXFIFOEMPTY_MASK			0x00000002
+#define ISR_NOACK_MASK				0x00000001
+
+#define CLKEN_OFFSET				0x0000004C
+#define CLKEN_AUTOSENSE_OFF_MASK		0x00000080
+#define CLKEN_M_SHIFT				4
+#define CLKEN_N_SHIFT				1
+#define CLKEN_CLKEN_MASK			0x00000001
+
+#define FIFO_STATUS_OFFSET			0x00000054
+#define FIFO_STATUS_RXFIFO_EMPTY_MASK		0x00000004
+#define FIFO_STATUS_TXFIFO_EMPTY_MASK		0x00000010
+
+#define HSTIM_OFFSET				0x00000058
+#define HSTIM_HS_MODE_MASK			0x00008000
+#define HSTIM_HS_HOLD_SHIFT			10
+#define HSTIM_HS_HIGH_PHASE_SHIFT		5
+#define HSTIM_HS_SETUP_SHIFT			0
+
+#define PADCTL_OFFSET				0x0000005c
+#define PADCTL_PAD_OUT_EN_MASK			0x00000004
+
+#define RXFCR_OFFSET				0x00000068
+#define RXFCR_NACK_EN_SHIFT			7
+#define RXFCR_READ_COUNT_SHIFT			0
+#define RXFIFORDOUT_OFFSET			0x0000006c
+
+/* Locally used constants */
+#define MAX_RX_FIFO_SIZE		64U /* bytes */
+#define MAX_TX_FIFO_SIZE		64U /* bytes */
+
+#define STD_EXT_CLK_FREQ		13000000UL
+#define HS_EXT_CLK_FREQ			104000000UL
+
+#define MASTERCODE			0x08 /* Mastercodes are 0000_1xxxb */
+
+#define I2C_TIMEOUT			100 /* msecs */
+
+/* Operations that can be commanded to the controller */
+enum bcm_kona_cmd_t {
+	BCM_CMD_NOACTION = 0,
+	BCM_CMD_START,
+	BCM_CMD_RESTART,
+	BCM_CMD_STOP,
+};
+
+enum bus_speed_index {
+	BCM_SPD_100K = 0,
+	BCM_SPD_400K,
+	BCM_SPD_1MHZ,
+};
+
+enum hs_bus_speed_index {
+	BCM_SPD_3P4MHZ = 0,
+};
+
+/* Internal divider settings for standard mode, fast mode and fast mode plus */
+struct bus_speed_cfg {
+	uint8_t time_m;		/* Number of cycles for setup time */
+	uint8_t time_n;		/* Number of cycles for hold time */
+	uint8_t prescale;	/* Prescale divider */
+	uint8_t time_p;		/* Timing coefficient */
+	uint8_t no_div;		/* Disable clock divider */
+	uint8_t time_div;	/* Post-prescale divider */
+};
+
+/* Internal divider settings for high-speed mode */
+struct hs_bus_speed_cfg {
+	uint8_t hs_hold;	/* Number of clock cycles SCL stays low until
+				   the end of bit period */
+	uint8_t hs_high_phase;	/* Number of clock cycles SCL stays high
+				   before it falls */
+	uint8_t hs_setup;	/* Number of clock cycles SCL stays low
+				   before it rises  */
+	uint8_t prescale;	/* Prescale divider */
+	uint8_t time_p;		/* Timing coefficient */
+	uint8_t no_div;		/* Disable clock divider */
+	uint8_t time_div;	/* Post-prescale divider */
+};
+
+static const struct bus_speed_cfg std_cfg_table[] = {
+	[BCM_SPD_100K] = {0x01, 0x01, 0x03, 0x06, 0x00, 0x02},
+	[BCM_SPD_400K] = {0x05, 0x01, 0x03, 0x05, 0x01, 0x02},
+	[BCM_SPD_1MHZ] = {0x01, 0x01, 0x03, 0x01, 0x01, 0x03},
+};
+
+static const struct hs_bus_speed_cfg hs_cfg_table[] = {
+	[BCM_SPD_3P4MHZ] = {0x01, 0x08, 0x14, 0x00, 0x06, 0x01, 0x00},
+};
+
+struct bcm_kona_i2c_dev {
+	struct device *device;
+
+	void __iomem *base;
+	int irq;
+	struct clk *external_clk;
+
+	struct i2c_adapter adapter;
+
+	struct completion done;
+
+	const struct bus_speed_cfg *std_cfg;
+	const struct hs_bus_speed_cfg *hs_cfg;
+};
+
+static void bcm_kona_i2c_send_cmd_to_ctrl(struct bcm_kona_i2c_dev *dev,
+					  enum bcm_kona_cmd_t cmd)
+{
+	dev_dbg(dev->device, "%s, %d\n", __func__, cmd);
+
+	switch (cmd) {
+	case BCM_CMD_NOACTION:
+		writel((CS_CMD_CMD_NO_ACTION << CS_CMD_SHIFT) |
+		       (CS_EN_CMD_ENABLE_BSC << CS_EN_SHIFT),
+		       dev->base + CS_OFFSET);
+		break;
+
+	case BCM_CMD_START:
+		writel((CS_ACK_CMD_GEN_START << CS_ACK_SHIFT) |
+		       (CS_CMD_CMD_START_RESTART << CS_CMD_SHIFT) |
+		       (CS_EN_CMD_ENABLE_BSC << CS_EN_SHIFT),
+		       dev->base + CS_OFFSET);
+		break;
+
+	case BCM_CMD_RESTART:
+		writel((CS_ACK_CMD_GEN_RESTART << CS_ACK_SHIFT) |
+		       (CS_CMD_CMD_START_RESTART << CS_CMD_SHIFT) |
+		       (CS_EN_CMD_ENABLE_BSC << CS_EN_SHIFT),
+		       dev->base + CS_OFFSET);
+		break;
+
+	case BCM_CMD_STOP:
+		writel((CS_CMD_CMD_STOP << CS_CMD_SHIFT) |
+		       (CS_EN_CMD_ENABLE_BSC << CS_EN_SHIFT),
+		       dev->base + CS_OFFSET);
+		break;
+
+	default:
+		dev_err(dev->device, "Unknown command %d\n", cmd);
+	}
+}
+
+static void bcm_kona_i2c_enable_clock(struct bcm_kona_i2c_dev *dev)
+{
+	writel(readl(dev->base + CLKEN_OFFSET) | CLKEN_CLKEN_MASK,
+	       dev->base + CLKEN_OFFSET);
+}
+
+static void bcm_kona_i2c_disable_clock(struct bcm_kona_i2c_dev *dev)
+{
+	writel(readl(dev->base + CLKEN_OFFSET) & ~CLKEN_CLKEN_MASK,
+	       dev->base + CLKEN_OFFSET);
+}
+
+static irqreturn_t bcm_kona_i2c_isr(int irq, void *devid)
+{
+	struct bcm_kona_i2c_dev *dev = devid;
+	uint32_t status = readl(dev->base + ISR_OFFSET);
+
+	if ((status & ~ISR_RESERVED_MASK) == 0)
+		return IRQ_NONE;
+
+	/* Must flush the TX FIFO when NAK detected */
+	if (status & ISR_NOACK_MASK)
+		writel(TXFCR_FIFO_FLUSH_MASK | TXFCR_FIFO_EN_MASK,
+		       dev->base + TXFCR_OFFSET);
+
+	writel(status & ~ISR_RESERVED_MASK, dev->base + ISR_OFFSET);
+	complete_all(&dev->done);
+
+	return IRQ_HANDLED;
+}
+
+/* Wait for ISR_CMDBUSY_MASK to go low before writing to CS, DAT, or RCD */
+static int bcm_kona_i2c_wait_if_busy(struct bcm_kona_i2c_dev *dev)
+{
+	unsigned long timeout = jiffies + msecs_to_jiffies(I2C_TIMEOUT);
+
+	while (readl(dev->base + ISR_OFFSET) & ISR_CMDBUSY_MASK)
+		if (time_after(jiffies, timeout)) {
+			dev_err(dev->device, "CMDBUSY timeout\n");
+			return -ETIMEDOUT;
+		}
+
+	return 0;
+}
+
+/* Send command to I2C bus */
+static int bcm_kona_send_i2c_cmd(struct bcm_kona_i2c_dev *dev,
+				 enum bcm_kona_cmd_t cmd)
+{
+	int rc;
+	unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT);
+
+	/* Make sure the hardware is ready */
+	rc = bcm_kona_i2c_wait_if_busy(dev);
+	if (rc < 0)
+		return rc;
+
+	/* Unmask the session done interrupt */
+	writel(IER_I2C_INT_EN_MASK, dev->base + IER_OFFSET);
+
+	/* Mark as incomplete before sending the command */
+	reinit_completion(&dev->done);
+
+	/* Send the command */
+	bcm_kona_i2c_send_cmd_to_ctrl(dev, cmd);
+
+	/* Wait for transaction to finish or timeout */
+	time_left = wait_for_completion_timeout(&dev->done, time_left);
+
+	/* Mask all interrupts */
+	writel(0, dev->base + IER_OFFSET);
+
+	if (!time_left) {
+		dev_err(dev->device, "controller timed out\n");
+		rc = -ETIMEDOUT;
+	}
+
+	/* Clear command */
+	bcm_kona_i2c_send_cmd_to_ctrl(dev, BCM_CMD_NOACTION);
+
+	return rc;
+}
+
+/* Read a single RX FIFO worth of data from the i2c bus */
+static int bcm_kona_i2c_read_fifo_single(struct bcm_kona_i2c_dev *dev,
+					 uint8_t *buf, unsigned int len,
+					 unsigned int last_byte_nak)
+{
+	unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT);
+
+	/* Mark as incomplete before starting the RX FIFO */
+	reinit_completion(&dev->done);
+
+	/* Unmask the read complete interrupt */
+	writel(IER_READ_COMPLETE_INT_MASK, dev->base + IER_OFFSET);
+
+	/* Start the RX FIFO */
+	writel((last_byte_nak << RXFCR_NACK_EN_SHIFT) |
+	       (len << RXFCR_READ_COUNT_SHIFT),
+		dev->base + RXFCR_OFFSET);
+
+	/* Wait for FIFO read to complete */
+	time_left = wait_for_completion_timeout(&dev->done, time_left);
+
+	/* Mask all interrupts */
+	writel(0, dev->base + IER_OFFSET);
+
+	if (!time_left) {
+		dev_err(dev->device, "RX FIFO time out\n");
+		return -EREMOTEIO;
+	}
+
+	/* Read data from FIFO */
+	for (; len > 0; len--, buf++)
+		*buf = readl(dev->base + RXFIFORDOUT_OFFSET);
+
+	return 0;
+}
+
+/* Read any amount of data using the RX FIFO from the i2c bus */
+static int bcm_kona_i2c_read_fifo(struct bcm_kona_i2c_dev *dev,
+				  struct i2c_msg *msg)
+{
+	unsigned int bytes_to_read = MAX_RX_FIFO_SIZE;
+	unsigned int last_byte_nak = 0;
+	unsigned int bytes_read = 0;
+	int rc;
+
+	uint8_t *tmp_buf = msg->buf;
+
+	while (bytes_read < msg->len) {
+		if (msg->len - bytes_read <= MAX_RX_FIFO_SIZE) {
+			last_byte_nak = 1; /* NAK last byte of transfer */
+			bytes_to_read = msg->len - bytes_read;
+		}
+
+		rc = bcm_kona_i2c_read_fifo_single(dev, tmp_buf, bytes_to_read,
+						   last_byte_nak);
+		if (rc < 0)
+			return -EREMOTEIO;
+
+		bytes_read += bytes_to_read;
+		tmp_buf += bytes_to_read;
+	}
+
+	return 0;
+}
+
+/* Write a single byte of data to the i2c bus */
+static int bcm_kona_i2c_write_byte(struct bcm_kona_i2c_dev *dev, uint8_t data,
+				   unsigned int nak_expected)
+{
+	int rc;
+	unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT);
+	unsigned int nak_received;
+
+	/* Make sure the hardware is ready */
+	rc = bcm_kona_i2c_wait_if_busy(dev);
+	if (rc < 0)
+		return rc;
+
+	/* Clear pending session done interrupt */
+	writel(ISR_SES_DONE_MASK, dev->base + ISR_OFFSET);
+
+	/* Unmask the session done interrupt */
+	writel(IER_I2C_INT_EN_MASK, dev->base + IER_OFFSET);
+
+	/* Mark as incomplete before sending the data */
+	reinit_completion(&dev->done);
+
+	/* Send one byte of data */
+	writel(data, dev->base + DAT_OFFSET);
+
+	/* Wait for byte to be written */
+	time_left = wait_for_completion_timeout(&dev->done, time_left);
+
+	/* Mask all interrupts */
+	writel(0, dev->base + IER_OFFSET);
+
+	if (!time_left) {
+		dev_dbg(dev->device, "controller timed out\n");
+		return -ETIMEDOUT;
+	}
+
+	nak_received = readl(dev->base + CS_OFFSET) & CS_ACK_MASK ? 1 : 0;
+
+	if (nak_received ^ nak_expected) {
+		dev_dbg(dev->device, "unexpected NAK/ACK\n");
+		return -EREMOTEIO;
+	}
+
+	return 0;
+}
+
+/* Write a single TX FIFO worth of data to the i2c bus */
+static int bcm_kona_i2c_write_fifo_single(struct bcm_kona_i2c_dev *dev,
+					  uint8_t *buf, unsigned int len)
+{
+	int k;
+	unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT);
+	unsigned int fifo_status;
+
+	/* Mark as incomplete before sending data to the TX FIFO */
+	reinit_completion(&dev->done);
+
+	/* Unmask the fifo empty and nak interrupt */
+	writel(IER_FIFO_INT_EN_MASK | IER_NOACK_EN_MASK,
+	       dev->base + IER_OFFSET);
+
+	/* Disable IRQ to load a FIFO worth of data without interruption */
+	disable_irq(dev->irq);
+
+	/* Write data into FIFO */
+	for (k = 0; k < len; k++)
+		writel(buf[k], (dev->base + DAT_OFFSET));
+
+	/* Enable IRQ now that data has been loaded */
+	enable_irq(dev->irq);
+
+	/* Wait for FIFO to empty */
+	do {
+		time_left = wait_for_completion_timeout(&dev->done, time_left);
+		fifo_status = readl(dev->base + FIFO_STATUS_OFFSET);
+	} while (time_left && !(fifo_status & FIFO_STATUS_TXFIFO_EMPTY_MASK));
+
+	/* Mask all interrupts */
+	writel(0, dev->base + IER_OFFSET);
+
+	/* Check if there was a NAK */
+	if (readl(dev->base + CS_OFFSET) & CS_ACK_MASK) {
+		dev_err(dev->device, "unexpected NAK\n");
+		return -EREMOTEIO;
+	}
+
+	/* Check if a timeout occured */
+	if (!time_left) {
+		dev_err(dev->device, "completion timed out\n");
+		return -EREMOTEIO;
+	}
+
+	return 0;
+}
+
+
+/* Write any amount of data using TX FIFO to the i2c bus */
+static int bcm_kona_i2c_write_fifo(struct bcm_kona_i2c_dev *dev,
+				   struct i2c_msg *msg)
+{
+	unsigned int bytes_to_write = MAX_TX_FIFO_SIZE;
+	unsigned int bytes_written = 0;
+	int rc;
+
+	uint8_t *tmp_buf = msg->buf;
+
+	while (bytes_written < msg->len) {
+		if (msg->len - bytes_written <= MAX_TX_FIFO_SIZE)
+			bytes_to_write = msg->len - bytes_written;
+
+		rc = bcm_kona_i2c_write_fifo_single(dev, tmp_buf,
+						    bytes_to_write);
+		if (rc < 0)
+			return -EREMOTEIO;
+
+		bytes_written += bytes_to_write;
+		tmp_buf += bytes_to_write;
+	}
+
+	return 0;
+}
+
+/* Send i2c address */
+static int bcm_kona_i2c_do_addr(struct bcm_kona_i2c_dev *dev,
+				     struct i2c_msg *msg)
+{
+	unsigned char addr;
+
+	if (msg->flags & I2C_M_TEN) {
+		/* First byte is 11110XX0 where XX is upper 2 bits */
+		addr = 0xF0 | ((msg->addr & 0x300) >> 7);
+		if (bcm_kona_i2c_write_byte(dev, addr, 0) < 0)
+			return -EREMOTEIO;
+
+		/* Second byte is the remaining 8 bits */
+		addr = msg->addr & 0xFF;
+		if (bcm_kona_i2c_write_byte(dev, addr, 0) < 0)
+			return -EREMOTEIO;
+
+		if (msg->flags & I2C_M_RD) {
+			/* For read, send restart command */
+			if (bcm_kona_send_i2c_cmd(dev, BCM_CMD_RESTART) < 0)
+				return -EREMOTEIO;
+
+			/* Then re-send the first byte with the read bit set */
+			addr = 0xF0 | ((msg->addr & 0x300) >> 7) | 0x01;
+			if (bcm_kona_i2c_write_byte(dev, addr, 0) < 0)
+				return -EREMOTEIO;
+		}
+	} else {
+		addr = msg->addr << 1;
+
+		if (msg->flags & I2C_M_RD)
+			addr |= 1;
+
+		if (bcm_kona_i2c_write_byte(dev, addr, 0) < 0)
+			return -EREMOTEIO;
+	}
+
+	return 0;
+}
+
+static void bcm_kona_i2c_enable_autosense(struct bcm_kona_i2c_dev *dev)
+{
+	writel(readl(dev->base + CLKEN_OFFSET) & ~CLKEN_AUTOSENSE_OFF_MASK,
+	       dev->base + CLKEN_OFFSET);
+}
+
+static void bcm_kona_i2c_config_timing(struct bcm_kona_i2c_dev *dev)
+{
+	writel(readl(dev->base + HSTIM_OFFSET) & ~HSTIM_HS_MODE_MASK,
+	       dev->base + HSTIM_OFFSET);
+
+	writel((dev->std_cfg->prescale << TIM_PRESCALE_SHIFT) |
+	       (dev->std_cfg->time_p << TIM_P_SHIFT) |
+	       (dev->std_cfg->no_div << TIM_NO_DIV_SHIFT) |
+	       (dev->std_cfg->time_div	<< TIM_DIV_SHIFT),
+	       dev->base + TIM_OFFSET);
+
+	writel((dev->std_cfg->time_m << CLKEN_M_SHIFT) |
+	       (dev->std_cfg->time_n << CLKEN_N_SHIFT) |
+	       CLKEN_CLKEN_MASK,
+	       dev->base + CLKEN_OFFSET);
+}
+
+static void bcm_kona_i2c_config_timing_hs(struct bcm_kona_i2c_dev *dev)
+{
+	writel((dev->hs_cfg->prescale << TIM_PRESCALE_SHIFT) |
+	       (dev->hs_cfg->time_p << TIM_P_SHIFT) |
+	       (dev->hs_cfg->no_div << TIM_NO_DIV_SHIFT) |
+	       (dev->hs_cfg->time_div << TIM_DIV_SHIFT),
+	       dev->base + TIM_OFFSET);
+
+	writel((dev->hs_cfg->hs_hold << HSTIM_HS_HOLD_SHIFT) |
+	       (dev->hs_cfg->hs_high_phase << HSTIM_HS_HIGH_PHASE_SHIFT) |
+	       (dev->hs_cfg->hs_setup << HSTIM_HS_SETUP_SHIFT),
+	       dev->base + HSTIM_OFFSET);
+
+	writel(readl(dev->base + HSTIM_OFFSET) | HSTIM_HS_MODE_MASK,
+	       dev->base + HSTIM_OFFSET);
+}
+
+static int bcm_kona_i2c_switch_to_hs(struct bcm_kona_i2c_dev *dev)
+{
+	int rc;
+
+	/* Send mastercode at standard speed */
+	rc = bcm_kona_i2c_write_byte(dev, MASTERCODE, 1);
+	if (rc < 0) {
+		pr_err("High speed handshake failed\n");
+		return rc;
+	}
+
+	/* Configure external clock to higher frequency */
+	rc = clk_set_rate(dev->external_clk, HS_EXT_CLK_FREQ);
+	if (rc) {
+		dev_err(dev->device, "%s: clk_set_rate returned %d\n",
+			__func__, rc);
+		return rc;
+	}
+
+	/* Reconfigure internal dividers */
+	bcm_kona_i2c_config_timing_hs(dev);
+
+	/* Send a restart command */
+	rc = bcm_kona_send_i2c_cmd(dev, BCM_CMD_RESTART);
+	if (rc < 0)
+		dev_err(dev->device, "High speed restart command failed\n");
+
+	return rc;
+}
+
+static int bcm_kona_i2c_switch_to_std(struct bcm_kona_i2c_dev *dev)
+{
+	int rc;
+
+	/* Reconfigure internal dividers */
+	bcm_kona_i2c_config_timing(dev);
+
+	/* Configure external clock to lower frequency */
+	rc = clk_set_rate(dev->external_clk, STD_EXT_CLK_FREQ);
+	if (rc) {
+		dev_err(dev->device, "%s: clk_set_rate returned %d\n",
+			__func__, rc);
+	}
+
+	return rc;
+}
+
+/* Master transfer function */
+static int bcm_kona_i2c_xfer(struct i2c_adapter *adapter,
+			     struct i2c_msg msgs[], int num)
+{
+	struct bcm_kona_i2c_dev *dev = i2c_get_adapdata(adapter);
+	struct i2c_msg *pmsg;
+	int rc = 0;
+	int i;
+
+	rc = clk_prepare_enable(dev->external_clk);
+	if (rc) {
+		dev_err(dev->device, "%s: peri clock enable failed. err %d\n",
+			__func__, rc);
+		return rc;
+	}
+
+	/* Enable pad output */
+	writel(0, dev->base + PADCTL_OFFSET);
+
+	/* Enable internal clocks */
+	bcm_kona_i2c_enable_clock(dev);
+
+	/* Send start command */
+	rc = bcm_kona_send_i2c_cmd(dev, BCM_CMD_START);
+	if (rc < 0) {
+		dev_err(dev->device, "Start command failed rc = %d\n", rc);
+		goto xfer_disable_pad;
+	}
+
+	/* Switch to high speed if applicable */
+	if (dev->hs_cfg) {
+		rc = bcm_kona_i2c_switch_to_hs(dev);
+		if (rc < 0)
+			goto xfer_send_stop;
+	}
+
+	/* Loop through all messages */
+	for (i = 0; i < num; i++) {
+		pmsg = &msgs[i];
+
+		/* Send restart for subsequent messages */
+		if ((i != 0) && ((pmsg->flags & I2C_M_NOSTART) == 0)) {
+			rc = bcm_kona_send_i2c_cmd(dev, BCM_CMD_RESTART);
+			if (rc < 0) {
+				dev_err(dev->device,
+					"restart cmd failed rc = %d\n", rc);
+					goto xfer_send_stop;
+			}
+		}
+
+		/* Send slave address */
+		if (!(pmsg->flags & I2C_M_NOSTART)) {
+			rc = bcm_kona_i2c_do_addr(dev, pmsg);
+			if (rc < 0) {
+				dev_err(dev->device,
+					"NAK from addr %2.2x msg#%d rc = %d\n",
+					pmsg->addr, i, rc);
+				goto xfer_send_stop;
+			}
+		}
+
+		/* Perform data transfer */
+		if (pmsg->flags & I2C_M_RD) {
+			rc = bcm_kona_i2c_read_fifo(dev, pmsg);
+			if (rc < 0) {
+				dev_err(dev->device, "read failure\n");
+				goto xfer_send_stop;
+			}
+		} else {
+			rc = bcm_kona_i2c_write_fifo(dev, pmsg);
+			if (rc < 0) {
+				dev_err(dev->device, "write failure");
+				goto xfer_send_stop;
+			}
+		}
+	}
+
+	rc = num;
+
+xfer_send_stop:
+	/* Send a STOP command */
+	bcm_kona_send_i2c_cmd(dev, BCM_CMD_STOP);
+
+	/* Return from high speed if applicable */
+	if (dev->hs_cfg) {
+		int hs_rc = bcm_kona_i2c_switch_to_std(dev);
+
+		if (hs_rc)
+			rc = hs_rc;
+	}
+
+xfer_disable_pad:
+	/* Disable pad output */
+	writel(PADCTL_PAD_OUT_EN_MASK, dev->base + PADCTL_OFFSET);
+
+	/* Stop internal clock */
+	bcm_kona_i2c_disable_clock(dev);
+
+	clk_disable_unprepare(dev->external_clk);
+
+	return rc;
+}
+
+static uint32_t bcm_kona_i2c_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_10BIT_ADDR |
+	    I2C_FUNC_NOSTART;
+}
+
+static const struct i2c_algorithm bcm_algo = {
+	.master_xfer = bcm_kona_i2c_xfer,
+	.functionality = bcm_kona_i2c_functionality,
+};
+
+static int bcm_kona_i2c_assign_bus_speed(struct bcm_kona_i2c_dev *dev)
+{
+	unsigned int bus_speed;
+	int ret = of_property_read_u32(dev->device->of_node, "clock-frequency",
+				       &bus_speed);
+	if (ret < 0) {
+		dev_err(dev->device, "missing clock-frequency property\n");
+		return -ENODEV;
+	}
+
+	switch (bus_speed) {
+	case 100000:
+		dev->std_cfg = &std_cfg_table[BCM_SPD_100K];
+		break;
+	case 400000:
+		dev->std_cfg = &std_cfg_table[BCM_SPD_400K];
+		break;
+	case 1000000:
+		dev->std_cfg = &std_cfg_table[BCM_SPD_1MHZ];
+		break;
+	case 3400000:
+		/* Send mastercode at 100k */
+		dev->std_cfg = &std_cfg_table[BCM_SPD_100K];
+		dev->hs_cfg = &hs_cfg_table[BCM_SPD_3P4MHZ];
+		break;
+	default:
+		pr_err("%d hz bus speed not supported\n", bus_speed);
+		pr_err("Valid speeds are 100khz, 400khz, 1mhz, and 3.4mhz\n");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int bcm_kona_i2c_probe(struct platform_device *pdev)
+{
+	int rc = 0;
+	struct bcm_kona_i2c_dev *dev;
+	struct i2c_adapter *adap;
+	struct resource *iomem;
+
+	/* Allocate memory for private data structure */
+	dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
+	if (!dev)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, dev);
+	dev->device = &pdev->dev;
+	init_completion(&dev->done);
+
+	/* Map hardware registers */
+	iomem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	dev->base = devm_ioremap_resource(dev->device, iomem);
+	if (IS_ERR(dev->base))
+		return -ENOMEM;
+
+	/* Get and enable external clock */
+	dev->external_clk = devm_clk_get(dev->device, NULL);
+	if (IS_ERR(dev->external_clk)) {
+		dev_err(dev->device, "couldn't get clock\n");
+		return -ENODEV;
+	}
+
+	rc = clk_set_rate(dev->external_clk, STD_EXT_CLK_FREQ);
+	if (rc) {
+		dev_err(dev->device, "%s: clk_set_rate returned %d\n",
+			__func__, rc);
+		return rc;
+	}
+
+	rc = clk_prepare_enable(dev->external_clk);
+	if (rc) {
+		dev_err(dev->device, "couldn't enable clock\n");
+		return rc;
+	}
+
+	/* Parse bus speed */
+	rc = bcm_kona_i2c_assign_bus_speed(dev);
+	if (rc)
+		goto probe_disable_clk;
+
+	/* Enable internal clocks */
+	bcm_kona_i2c_enable_clock(dev);
+
+	/* Configure internal dividers */
+	bcm_kona_i2c_config_timing(dev);
+
+	/* Disable timeout */
+	writel(0, dev->base + TOUT_OFFSET);
+
+	/* Enable autosense */
+	bcm_kona_i2c_enable_autosense(dev);
+
+	/* Enable TX FIFO */
+	writel(TXFCR_FIFO_FLUSH_MASK | TXFCR_FIFO_EN_MASK,
+	       dev->base + TXFCR_OFFSET);
+
+	/* Mask all interrupts */
+	writel(0, dev->base + IER_OFFSET);
+
+	/* Clear all pending interrupts */
+	writel(ISR_CMDBUSY_MASK |
+	       ISR_READ_COMPLETE_MASK |
+	       ISR_SES_DONE_MASK |
+	       ISR_ERR_MASK |
+	       ISR_TXFIFOEMPTY_MASK |
+	       ISR_NOACK_MASK,
+	       dev->base + ISR_OFFSET);
+
+	/* Get the interrupt number */
+	dev->irq = platform_get_irq(pdev, 0);
+	if (dev->irq < 0) {
+		dev_err(dev->device, "no irq resource\n");
+		rc = -ENODEV;
+		goto probe_disable_clk;
+	}
+
+	/* register the ISR handler */
+	rc = devm_request_irq(&pdev->dev, dev->irq, bcm_kona_i2c_isr,
+			      IRQF_SHARED, pdev->name, dev);
+	if (rc) {
+		dev_err(dev->device, "failed to request irq %i\n", dev->irq);
+		goto probe_disable_clk;
+	}
+
+	/* Enable the controller but leave it idle */
+	bcm_kona_i2c_send_cmd_to_ctrl(dev, BCM_CMD_NOACTION);
+
+	/* Disable pad output */
+	writel(PADCTL_PAD_OUT_EN_MASK, dev->base + PADCTL_OFFSET);
+
+	/* Disable internal clock */
+	bcm_kona_i2c_disable_clock(dev);
+
+	/* Disable external clock */
+	clk_disable_unprepare(dev->external_clk);
+
+	/* Add the i2c adapter */
+	adap = &dev->adapter;
+	i2c_set_adapdata(adap, dev);
+	adap->owner = THIS_MODULE;
+	strlcpy(adap->name, "Broadcom I2C adapter", sizeof(adap->name));
+	adap->algo = &bcm_algo;
+	adap->dev.parent = &pdev->dev;
+	adap->dev.of_node = pdev->dev.of_node;
+
+	rc = i2c_add_adapter(adap);
+	if (rc) {
+		dev_err(dev->device, "failed to add adapter\n");
+		return rc;
+	}
+
+	dev_info(dev->device, "device registered successfully\n");
+
+	return 0;
+
+probe_disable_clk:
+	bcm_kona_i2c_disable_clock(dev);
+	clk_disable_unprepare(dev->external_clk);
+
+	return rc;
+}
+
+static int bcm_kona_i2c_remove(struct platform_device *pdev)
+{
+	struct bcm_kona_i2c_dev *dev = platform_get_drvdata(pdev);
+
+	i2c_del_adapter(&dev->adapter);
+
+	return 0;
+}
+
+static const struct of_device_id bcm_kona_i2c_of_match[] = {
+	{.compatible = "brcm,kona-i2c",},
+	{},
+};
+MODULE_DEVICE_TABLE(of, kona_i2c_of_match);
+
+static struct platform_driver bcm_kona_i2c_driver = {
+	.driver = {
+		   .name = "bcm-kona-i2c",
+		   .owner = THIS_MODULE,
+		   .of_match_table = bcm_kona_i2c_of_match,
+		   },
+	.probe = bcm_kona_i2c_probe,
+	.remove = bcm_kona_i2c_remove,
+};
+module_platform_driver(bcm_kona_i2c_driver);
+
+MODULE_AUTHOR("Tim Kryger <tkryger@broadcom.com>");
+MODULE_DESCRIPTION("Broadcom Kona I2C Driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/i2c/busses/i2c-bfin-twi.c b/drivers/i2c/busses/i2c-bfin-twi.c
index 35a473ba3d81..3b9bd9a3f2b0 100644
--- a/drivers/i2c/busses/i2c-bfin-twi.c
+++ b/drivers/i2c/busses/i2c-bfin-twi.c
@@ -675,7 +675,7 @@ static int i2c_bfin_twi_probe(struct platform_device *pdev)
 	p_adap->retries = 3;
 
 	rc = peripheral_request_list(
-			(unsigned short *)dev_get_platdata(&pdev->dev),
+			dev_get_platdata(&pdev->dev),
 			"i2c-bfin-twi");
 	if (rc) {
 		dev_err(&pdev->dev, "Can't setup pin mux!\n");
@@ -723,7 +723,7 @@ out_error_add_adapter:
 	free_irq(iface->irq, iface);
 out_error_req_irq:
 out_error_no_irq:
-	peripheral_free_list((unsigned short *)dev_get_platdata(&pdev->dev));
+	peripheral_free_list(dev_get_platdata(&pdev->dev));
 out_error_pin_mux:
 	iounmap(iface->regs_base);
 out_error_ioremap:
@@ -739,7 +739,7 @@ static int i2c_bfin_twi_remove(struct platform_device *pdev)
 
 	i2c_del_adapter(&(iface->adap));
 	free_irq(iface->irq, iface);
-	peripheral_free_list((unsigned short *)dev_get_platdata(&pdev->dev));
+	peripheral_free_list(dev_get_platdata(&pdev->dev));
 	iounmap(iface->regs_base);
 	kfree(iface);
 
diff --git a/drivers/i2c/busses/i2c-cbus-gpio.c b/drivers/i2c/busses/i2c-cbus-gpio.c
index 2d46f13adfdf..ce7ffba2b020 100644
--- a/drivers/i2c/busses/i2c-cbus-gpio.c
+++ b/drivers/i2c/busses/i2c-cbus-gpio.c
@@ -246,6 +246,7 @@ static int cbus_i2c_probe(struct platform_device *pdev)
 	adapter->owner		= THIS_MODULE;
 	adapter->class		= I2C_CLASS_HWMON;
 	adapter->dev.parent	= &pdev->dev;
+	adapter->dev.of_node	= pdev->dev.of_node;
 	adapter->nr		= pdev->id;
 	adapter->timeout	= HZ;
 	adapter->algo		= &cbus_i2c_algo;
@@ -289,6 +290,7 @@ static struct platform_driver cbus_i2c_driver = {
 	.driver	= {
 		.owner	= THIS_MODULE,
 		.name	= "i2c-cbus-gpio",
+		.of_match_table = of_match_ptr(i2c_cbus_dt_ids),
 	},
 };
 module_platform_driver(cbus_i2c_driver);
diff --git a/drivers/i2c/busses/i2c-davinci.c b/drivers/i2c/busses/i2c-davinci.c
index 960dec61c64e..ff05d9fef4a8 100644
--- a/drivers/i2c/busses/i2c-davinci.c
+++ b/drivers/i2c/busses/i2c-davinci.c
@@ -795,7 +795,7 @@ static struct platform_driver davinci_i2c_driver = {
 		.name	= "i2c_davinci",
 		.owner	= THIS_MODULE,
 		.pm	= davinci_i2c_pm_ops,
-		.of_match_table = of_match_ptr(davinci_i2c_of_match),
+		.of_match_table = davinci_i2c_of_match,
 	},
 };
 
diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 0aa01136f8d9..d0bdac0498ce 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -103,6 +103,8 @@ static int dw_i2c_acpi_configure(struct platform_device *pdev)
 static const struct acpi_device_id dw_i2c_acpi_match[] = {
 	{ "INT33C2", 0 },
 	{ "INT33C3", 0 },
+	{ "INT3432", 0 },
+	{ "INT3433", 0 },
 	{ "80860F41", 0 },
 	{ }
 };
diff --git a/drivers/i2c/busses/i2c-eg20t.c b/drivers/i2c/busses/i2c-eg20t.c
index 0f3752967c4b..ff15ae90aaf5 100644
--- a/drivers/i2c/busses/i2c-eg20t.c
+++ b/drivers/i2c/busses/i2c-eg20t.c
@@ -312,24 +312,6 @@ static void pch_i2c_start(struct i2c_algo_pch_data *adap)
 }
 
 /**
- * pch_i2c_getack() - to confirm ACK/NACK
- * @adap:	Pointer to struct i2c_algo_pch_data.
- */
-static s32 pch_i2c_getack(struct i2c_algo_pch_data *adap)
-{
-	u32 reg_val;
-	void __iomem *p = adap->pch_base_address;
-	reg_val = ioread32(p + PCH_I2CSR) & PCH_GETACK;
-
-	if (reg_val != 0) {
-		pch_err(adap, "return%d\n", -EPROTO);
-		return -EPROTO;
-	}
-
-	return 0;
-}
-
-/**
  * pch_i2c_stop() - generate stop condition in normal mode.
  * @adap:	Pointer to struct i2c_algo_pch_data.
  */
@@ -344,6 +326,7 @@ static void pch_i2c_stop(struct i2c_algo_pch_data *adap)
 static int pch_i2c_wait_for_check_xfer(struct i2c_algo_pch_data *adap)
 {
 	long ret;
+	void __iomem *p = adap->pch_base_address;
 
 	ret = wait_event_timeout(pch_event,
 			(adap->pch_event_flag != 0), msecs_to_jiffies(1000));
@@ -366,10 +349,9 @@ static int pch_i2c_wait_for_check_xfer(struct i2c_algo_pch_data *adap)
 
 	adap->pch_event_flag = 0;
 
-	if (pch_i2c_getack(adap)) {
-		pch_dbg(adap, "Receive NACK for slave address"
-			"setting\n");
-		return -EIO;
+	if (ioread32(p + PCH_I2CSR) & PCH_GETACK) {
+		pch_dbg(adap, "Receive NACK for slave address setting\n");
+		return -ENXIO;
 	}
 
 	return 0;
diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c
new file mode 100644
index 000000000000..c1ef228095b5
--- /dev/null
+++ b/drivers/i2c/busses/i2c-exynos5.c
@@ -0,0 +1,769 @@
+/**
+ * i2c-exynos5.c - Samsung Exynos5 I2C Controller Driver
+ *
+ * Copyright (C) 2013 Samsung Electronics Co., 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.
+*/
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/err.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/spinlock.h>
+
+/*
+ * HSI2C controller from Samsung supports 2 modes of operation
+ * 1. Auto mode: Where in master automatically controls the whole transaction
+ * 2. Manual mode: Software controls the transaction by issuing commands
+ *    START, READ, WRITE, STOP, RESTART in I2C_MANUAL_CMD register.
+ *
+ * Operation mode can be selected by setting AUTO_MODE bit in I2C_CONF register
+ *
+ * Special bits are available for both modes of operation to set commands
+ * and for checking transfer status
+ */
+
+/* Register Map */
+#define HSI2C_CTL		0x00
+#define HSI2C_FIFO_CTL		0x04
+#define HSI2C_TRAILIG_CTL	0x08
+#define HSI2C_CLK_CTL		0x0C
+#define HSI2C_CLK_SLOT		0x10
+#define HSI2C_INT_ENABLE	0x20
+#define HSI2C_INT_STATUS	0x24
+#define HSI2C_ERR_STATUS	0x2C
+#define HSI2C_FIFO_STATUS	0x30
+#define HSI2C_TX_DATA		0x34
+#define HSI2C_RX_DATA		0x38
+#define HSI2C_CONF		0x40
+#define HSI2C_AUTO_CONF		0x44
+#define HSI2C_TIMEOUT		0x48
+#define HSI2C_MANUAL_CMD	0x4C
+#define HSI2C_TRANS_STATUS	0x50
+#define HSI2C_TIMING_HS1	0x54
+#define HSI2C_TIMING_HS2	0x58
+#define HSI2C_TIMING_HS3	0x5C
+#define HSI2C_TIMING_FS1	0x60
+#define HSI2C_TIMING_FS2	0x64
+#define HSI2C_TIMING_FS3	0x68
+#define HSI2C_TIMING_SLA	0x6C
+#define HSI2C_ADDR		0x70
+
+/* I2C_CTL Register bits */
+#define HSI2C_FUNC_MODE_I2C			(1u << 0)
+#define HSI2C_MASTER				(1u << 3)
+#define HSI2C_RXCHON				(1u << 6)
+#define HSI2C_TXCHON				(1u << 7)
+#define HSI2C_SW_RST				(1u << 31)
+
+/* I2C_FIFO_CTL Register bits */
+#define HSI2C_RXFIFO_EN				(1u << 0)
+#define HSI2C_TXFIFO_EN				(1u << 1)
+#define HSI2C_RXFIFO_TRIGGER_LEVEL(x)		((x) << 4)
+#define HSI2C_TXFIFO_TRIGGER_LEVEL(x)		((x) << 16)
+
+/* As per user manual FIFO max depth is 64bytes */
+#define HSI2C_FIFO_MAX				0x40
+/* default trigger levels for Tx and Rx FIFOs */
+#define HSI2C_DEF_TXFIFO_LVL			(HSI2C_FIFO_MAX - 0x30)
+#define HSI2C_DEF_RXFIFO_LVL			(HSI2C_FIFO_MAX - 0x10)
+
+/* I2C_TRAILING_CTL Register bits */
+#define HSI2C_TRAILING_COUNT			(0xf)
+
+/* I2C_INT_EN Register bits */
+#define HSI2C_INT_TX_ALMOSTEMPTY_EN		(1u << 0)
+#define HSI2C_INT_RX_ALMOSTFULL_EN		(1u << 1)
+#define HSI2C_INT_TRAILING_EN			(1u << 6)
+#define HSI2C_INT_I2C_EN			(1u << 9)
+
+/* I2C_INT_STAT Register bits */
+#define HSI2C_INT_TX_ALMOSTEMPTY		(1u << 0)
+#define HSI2C_INT_RX_ALMOSTFULL			(1u << 1)
+#define HSI2C_INT_TX_UNDERRUN			(1u << 2)
+#define HSI2C_INT_TX_OVERRUN			(1u << 3)
+#define HSI2C_INT_RX_UNDERRUN			(1u << 4)
+#define HSI2C_INT_RX_OVERRUN			(1u << 5)
+#define HSI2C_INT_TRAILING			(1u << 6)
+#define HSI2C_INT_I2C				(1u << 9)
+
+/* I2C_FIFO_STAT Register bits */
+#define HSI2C_RX_FIFO_EMPTY			(1u << 24)
+#define HSI2C_RX_FIFO_FULL			(1u << 23)
+#define HSI2C_RX_FIFO_LVL(x)			((x >> 16) & 0x7f)
+#define HSI2C_TX_FIFO_EMPTY			(1u << 8)
+#define HSI2C_TX_FIFO_FULL			(1u << 7)
+#define HSI2C_TX_FIFO_LVL(x)			((x >> 0) & 0x7f)
+
+/* I2C_CONF Register bits */
+#define HSI2C_AUTO_MODE				(1u << 31)
+#define HSI2C_10BIT_ADDR_MODE			(1u << 30)
+#define HSI2C_HS_MODE				(1u << 29)
+
+/* I2C_AUTO_CONF Register bits */
+#define HSI2C_READ_WRITE			(1u << 16)
+#define HSI2C_STOP_AFTER_TRANS			(1u << 17)
+#define HSI2C_MASTER_RUN			(1u << 31)
+
+/* I2C_TIMEOUT Register bits */
+#define HSI2C_TIMEOUT_EN			(1u << 31)
+#define HSI2C_TIMEOUT_MASK			0xff
+
+/* I2C_TRANS_STATUS register bits */
+#define HSI2C_MASTER_BUSY			(1u << 17)
+#define HSI2C_SLAVE_BUSY			(1u << 16)
+#define HSI2C_TIMEOUT_AUTO			(1u << 4)
+#define HSI2C_NO_DEV				(1u << 3)
+#define HSI2C_NO_DEV_ACK			(1u << 2)
+#define HSI2C_TRANS_ABORT			(1u << 1)
+#define HSI2C_TRANS_DONE			(1u << 0)
+
+/* I2C_ADDR register bits */
+#define HSI2C_SLV_ADDR_SLV(x)			((x & 0x3ff) << 0)
+#define HSI2C_SLV_ADDR_MAS(x)			((x & 0x3ff) << 10)
+#define HSI2C_MASTER_ID(x)			((x & 0xff) << 24)
+#define MASTER_ID(x)				((x & 0x7) + 0x08)
+
+/*
+ * Controller operating frequency, timing values for operation
+ * are calculated against this frequency
+ */
+#define HSI2C_HS_TX_CLOCK	1000000
+#define HSI2C_FS_TX_CLOCK	100000
+#define HSI2C_HIGH_SPD		1
+#define HSI2C_FAST_SPD		0
+
+#define EXYNOS5_I2C_TIMEOUT (msecs_to_jiffies(1000))
+
+struct exynos5_i2c {
+	struct i2c_adapter	adap;
+	unsigned int		suspended:1;
+
+	struct i2c_msg		*msg;
+	struct completion	msg_complete;
+	unsigned int		msg_ptr;
+
+	unsigned int		irq;
+
+	void __iomem		*regs;
+	struct clk		*clk;
+	struct device		*dev;
+	int			state;
+
+	spinlock_t		lock;		/* IRQ synchronization */
+
+	/*
+	 * Since the TRANS_DONE bit is cleared on read, and we may read it
+	 * either during an IRQ or after a transaction, keep track of its
+	 * state here.
+	 */
+	int			trans_done;
+
+	/* Controller operating frequency */
+	unsigned int		fs_clock;
+	unsigned int		hs_clock;
+
+	/*
+	 * HSI2C Controller can operate in
+	 * 1. High speed upto 3.4Mbps
+	 * 2. Fast speed upto 1Mbps
+	 */
+	int			speed_mode;
+};
+
+static const struct of_device_id exynos5_i2c_match[] = {
+	{ .compatible = "samsung,exynos5-hsi2c" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, exynos5_i2c_match);
+
+static void exynos5_i2c_clr_pend_irq(struct exynos5_i2c *i2c)
+{
+	writel(readl(i2c->regs + HSI2C_INT_STATUS),
+				i2c->regs + HSI2C_INT_STATUS);
+}
+
+/*
+ * exynos5_i2c_set_timing: updates the registers with appropriate
+ * timing values calculated
+ *
+ * Returns 0 on success, -EINVAL if the cycle length cannot
+ * be calculated.
+ */
+static int exynos5_i2c_set_timing(struct exynos5_i2c *i2c, int mode)
+{
+	u32 i2c_timing_s1;
+	u32 i2c_timing_s2;
+	u32 i2c_timing_s3;
+	u32 i2c_timing_sla;
+	unsigned int t_start_su, t_start_hd;
+	unsigned int t_stop_su;
+	unsigned int t_data_su, t_data_hd;
+	unsigned int t_scl_l, t_scl_h;
+	unsigned int t_sr_release;
+	unsigned int t_ftl_cycle;
+	unsigned int clkin = clk_get_rate(i2c->clk);
+	unsigned int div, utemp0 = 0, utemp1 = 0, clk_cycle;
+	unsigned int op_clk = (mode == HSI2C_HIGH_SPD) ?
+				i2c->hs_clock : i2c->fs_clock;
+
+	/*
+	 * FPCLK / FI2C =
+	 * (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2) + 8 + 2 * FLT_CYCLE
+	 * utemp0 = (CLK_DIV + 1) * (TSCLK_L + TSCLK_H + 2)
+	 * utemp1 = (TSCLK_L + TSCLK_H + 2)
+	 */
+	t_ftl_cycle = (readl(i2c->regs + HSI2C_CONF) >> 16) & 0x7;
+	utemp0 = (clkin / op_clk) - 8 - 2 * t_ftl_cycle;
+
+	/* CLK_DIV max is 256 */
+	for (div = 0; div < 256; div++) {
+		utemp1 = utemp0 / (div + 1);
+
+		/*
+		 * SCL_L and SCL_H each has max value of 255
+		 * Hence, For the clk_cycle to the have right value
+		 * utemp1 has to be less then 512 and more than 4.
+		 */
+		if ((utemp1 < 512) && (utemp1 > 4)) {
+			clk_cycle = utemp1 - 2;
+			break;
+		} else if (div == 255) {
+			dev_warn(i2c->dev, "Failed to calculate divisor");
+			return -EINVAL;
+		}
+	}
+
+	t_scl_l = clk_cycle / 2;
+	t_scl_h = clk_cycle / 2;
+	t_start_su = t_scl_l;
+	t_start_hd = t_scl_l;
+	t_stop_su = t_scl_l;
+	t_data_su = t_scl_l / 2;
+	t_data_hd = t_scl_l / 2;
+	t_sr_release = clk_cycle;
+
+	i2c_timing_s1 = t_start_su << 24 | t_start_hd << 16 | t_stop_su << 8;
+	i2c_timing_s2 = t_data_su << 24 | t_scl_l << 8 | t_scl_h << 0;
+	i2c_timing_s3 = div << 16 | t_sr_release << 0;
+	i2c_timing_sla = t_data_hd << 0;
+
+	dev_dbg(i2c->dev, "tSTART_SU: %X, tSTART_HD: %X, tSTOP_SU: %X\n",
+		t_start_su, t_start_hd, t_stop_su);
+	dev_dbg(i2c->dev, "tDATA_SU: %X, tSCL_L: %X, tSCL_H: %X\n",
+		t_data_su, t_scl_l, t_scl_h);
+	dev_dbg(i2c->dev, "nClkDiv: %X, tSR_RELEASE: %X\n",
+		div, t_sr_release);
+	dev_dbg(i2c->dev, "tDATA_HD: %X\n", t_data_hd);
+
+	if (mode == HSI2C_HIGH_SPD) {
+		writel(i2c_timing_s1, i2c->regs + HSI2C_TIMING_HS1);
+		writel(i2c_timing_s2, i2c->regs + HSI2C_TIMING_HS2);
+		writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_HS3);
+	} else {
+		writel(i2c_timing_s1, i2c->regs + HSI2C_TIMING_FS1);
+		writel(i2c_timing_s2, i2c->regs + HSI2C_TIMING_FS2);
+		writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_FS3);
+	}
+	writel(i2c_timing_sla, i2c->regs + HSI2C_TIMING_SLA);
+
+	return 0;
+}
+
+static int exynos5_hsi2c_clock_setup(struct exynos5_i2c *i2c)
+{
+	/*
+	 * Configure the Fast speed timing values
+	 * Even the High Speed mode initially starts with Fast mode
+	 */
+	if (exynos5_i2c_set_timing(i2c, HSI2C_FAST_SPD)) {
+		dev_err(i2c->dev, "HSI2C FS Clock set up failed\n");
+		return -EINVAL;
+	}
+
+	/* configure the High speed timing values */
+	if (i2c->speed_mode == HSI2C_HIGH_SPD) {
+		if (exynos5_i2c_set_timing(i2c, HSI2C_HIGH_SPD)) {
+			dev_err(i2c->dev, "HSI2C HS Clock set up failed\n");
+			return -EINVAL;
+		}
+	}
+
+	return 0;
+}
+
+/*
+ * exynos5_i2c_init: configures the controller for I2C functionality
+ * Programs I2C controller for Master mode operation
+ */
+static void exynos5_i2c_init(struct exynos5_i2c *i2c)
+{
+	u32 i2c_conf = readl(i2c->regs + HSI2C_CONF);
+	u32 i2c_timeout = readl(i2c->regs + HSI2C_TIMEOUT);
+
+	/* Clear to disable Timeout */
+	i2c_timeout &= ~HSI2C_TIMEOUT_EN;
+	writel(i2c_timeout, i2c->regs + HSI2C_TIMEOUT);
+
+	writel((HSI2C_FUNC_MODE_I2C | HSI2C_MASTER),
+					i2c->regs + HSI2C_CTL);
+	writel(HSI2C_TRAILING_COUNT, i2c->regs + HSI2C_TRAILIG_CTL);
+
+	if (i2c->speed_mode == HSI2C_HIGH_SPD) {
+		writel(HSI2C_MASTER_ID(MASTER_ID(i2c->adap.nr)),
+					i2c->regs + HSI2C_ADDR);
+		i2c_conf |= HSI2C_HS_MODE;
+	}
+
+	writel(i2c_conf | HSI2C_AUTO_MODE, i2c->regs + HSI2C_CONF);
+}
+
+static void exynos5_i2c_reset(struct exynos5_i2c *i2c)
+{
+	u32 i2c_ctl;
+
+	/* Set and clear the bit for reset */
+	i2c_ctl = readl(i2c->regs + HSI2C_CTL);
+	i2c_ctl |= HSI2C_SW_RST;
+	writel(i2c_ctl, i2c->regs + HSI2C_CTL);
+
+	i2c_ctl = readl(i2c->regs + HSI2C_CTL);
+	i2c_ctl &= ~HSI2C_SW_RST;
+	writel(i2c_ctl, i2c->regs + HSI2C_CTL);
+
+	/* We don't expect calculations to fail during the run */
+	exynos5_hsi2c_clock_setup(i2c);
+	/* Initialize the configure registers */
+	exynos5_i2c_init(i2c);
+}
+
+/*
+ * exynos5_i2c_irq: top level IRQ servicing routine
+ *
+ * INT_STATUS registers gives the interrupt details. Further,
+ * FIFO_STATUS or TRANS_STATUS registers are to be check for detailed
+ * state of the bus.
+ */
+static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id)
+{
+	struct exynos5_i2c *i2c = dev_id;
+	u32 fifo_level, int_status, fifo_status, trans_status;
+	unsigned char byte;
+	int len = 0;
+
+	i2c->state = -EINVAL;
+
+	spin_lock(&i2c->lock);
+
+	int_status = readl(i2c->regs + HSI2C_INT_STATUS);
+	writel(int_status, i2c->regs + HSI2C_INT_STATUS);
+	fifo_status = readl(i2c->regs + HSI2C_FIFO_STATUS);
+
+	/* handle interrupt related to the transfer status */
+	if (int_status & HSI2C_INT_I2C) {
+		trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS);
+		if (trans_status & HSI2C_NO_DEV_ACK) {
+			dev_dbg(i2c->dev, "No ACK from device\n");
+			i2c->state = -ENXIO;
+			goto stop;
+		} else if (trans_status & HSI2C_NO_DEV) {
+			dev_dbg(i2c->dev, "No device\n");
+			i2c->state = -ENXIO;
+			goto stop;
+		} else if (trans_status & HSI2C_TRANS_ABORT) {
+			dev_dbg(i2c->dev, "Deal with arbitration lose\n");
+			i2c->state = -EAGAIN;
+			goto stop;
+		} else if (trans_status & HSI2C_TIMEOUT_AUTO) {
+			dev_dbg(i2c->dev, "Accessing device timed out\n");
+			i2c->state = -EAGAIN;
+			goto stop;
+		} else if (trans_status & HSI2C_TRANS_DONE) {
+			i2c->trans_done = 1;
+			i2c->state = 0;
+		}
+	}
+
+	if ((i2c->msg->flags & I2C_M_RD) && (int_status &
+			(HSI2C_INT_TRAILING | HSI2C_INT_RX_ALMOSTFULL))) {
+		fifo_status = readl(i2c->regs + HSI2C_FIFO_STATUS);
+		fifo_level = HSI2C_RX_FIFO_LVL(fifo_status);
+		len = min(fifo_level, i2c->msg->len - i2c->msg_ptr);
+
+		while (len > 0) {
+			byte = (unsigned char)
+				readl(i2c->regs + HSI2C_RX_DATA);
+			i2c->msg->buf[i2c->msg_ptr++] = byte;
+			len--;
+		}
+		i2c->state = 0;
+	} else if (int_status & HSI2C_INT_TX_ALMOSTEMPTY) {
+		fifo_status = readl(i2c->regs + HSI2C_FIFO_STATUS);
+		fifo_level = HSI2C_TX_FIFO_LVL(fifo_status);
+
+		len = HSI2C_FIFO_MAX - fifo_level;
+		if (len > (i2c->msg->len - i2c->msg_ptr))
+			len = i2c->msg->len - i2c->msg_ptr;
+
+		while (len > 0) {
+			byte = i2c->msg->buf[i2c->msg_ptr++];
+			writel(byte, i2c->regs + HSI2C_TX_DATA);
+			len--;
+		}
+		i2c->state = 0;
+	}
+
+ stop:
+	if ((i2c->trans_done && (i2c->msg->len == i2c->msg_ptr)) ||
+	    (i2c->state < 0)) {
+		writel(0, i2c->regs + HSI2C_INT_ENABLE);
+		exynos5_i2c_clr_pend_irq(i2c);
+		complete(&i2c->msg_complete);
+	}
+
+	spin_unlock(&i2c->lock);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * exynos5_i2c_wait_bus_idle
+ *
+ * Wait for the bus to go idle, indicated by the MASTER_BUSY bit being
+ * cleared.
+ *
+ * Returns -EBUSY if the bus cannot be bought to idle
+ */
+static int exynos5_i2c_wait_bus_idle(struct exynos5_i2c *i2c)
+{
+	unsigned long stop_time;
+	u32 trans_status;
+
+	/* wait for 100 milli seconds for the bus to be idle */
+	stop_time = jiffies + msecs_to_jiffies(100) + 1;
+	do {
+		trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS);
+		if (!(trans_status & HSI2C_MASTER_BUSY))
+			return 0;
+
+		usleep_range(50, 200);
+	} while (time_before(jiffies, stop_time));
+
+	return -EBUSY;
+}
+
+/*
+ * exynos5_i2c_message_start: Configures the bus and starts the xfer
+ * i2c: struct exynos5_i2c pointer for the current bus
+ * stop: Enables stop after transfer if set. Set for last transfer of
+ *       in the list of messages.
+ *
+ * Configures the bus for read/write function
+ * Sets chip address to talk to, message length to be sent.
+ * Enables appropriate interrupts and sends start xfer command.
+ */
+static void exynos5_i2c_message_start(struct exynos5_i2c *i2c, int stop)
+{
+	u32 i2c_ctl;
+	u32 int_en = HSI2C_INT_I2C_EN;
+	u32 i2c_auto_conf = 0;
+	u32 fifo_ctl;
+	unsigned long flags;
+
+	i2c_ctl = readl(i2c->regs + HSI2C_CTL);
+	i2c_ctl &= ~(HSI2C_TXCHON | HSI2C_RXCHON);
+	fifo_ctl = HSI2C_RXFIFO_EN | HSI2C_TXFIFO_EN;
+
+	if (i2c->msg->flags & I2C_M_RD) {
+		i2c_ctl |= HSI2C_RXCHON;
+
+		i2c_auto_conf = HSI2C_READ_WRITE;
+
+		fifo_ctl |= HSI2C_RXFIFO_TRIGGER_LEVEL(HSI2C_DEF_TXFIFO_LVL);
+		int_en |= (HSI2C_INT_RX_ALMOSTFULL_EN |
+			HSI2C_INT_TRAILING_EN);
+	} else {
+		i2c_ctl |= HSI2C_TXCHON;
+
+		fifo_ctl |= HSI2C_TXFIFO_TRIGGER_LEVEL(HSI2C_DEF_RXFIFO_LVL);
+		int_en |= HSI2C_INT_TX_ALMOSTEMPTY_EN;
+	}
+
+	writel(HSI2C_SLV_ADDR_MAS(i2c->msg->addr), i2c->regs + HSI2C_ADDR);
+
+	writel(fifo_ctl, i2c->regs + HSI2C_FIFO_CTL);
+	writel(i2c_ctl, i2c->regs + HSI2C_CTL);
+
+
+	/*
+	 * Enable interrupts before starting the transfer so that we don't
+	 * miss any INT_I2C interrupts.
+	 */
+	spin_lock_irqsave(&i2c->lock, flags);
+	writel(int_en, i2c->regs + HSI2C_INT_ENABLE);
+
+	if (stop == 1)
+		i2c_auto_conf |= HSI2C_STOP_AFTER_TRANS;
+	i2c_auto_conf |= i2c->msg->len;
+	i2c_auto_conf |= HSI2C_MASTER_RUN;
+	writel(i2c_auto_conf, i2c->regs + HSI2C_AUTO_CONF);
+	spin_unlock_irqrestore(&i2c->lock, flags);
+}
+
+static int exynos5_i2c_xfer_msg(struct exynos5_i2c *i2c,
+			      struct i2c_msg *msgs, int stop)
+{
+	unsigned long timeout;
+	int ret;
+
+	i2c->msg = msgs;
+	i2c->msg_ptr = 0;
+	i2c->trans_done = 0;
+
+	reinit_completion(&i2c->msg_complete);
+
+	exynos5_i2c_message_start(i2c, stop);
+
+	timeout = wait_for_completion_timeout(&i2c->msg_complete,
+					      EXYNOS5_I2C_TIMEOUT);
+	if (timeout == 0)
+		ret = -ETIMEDOUT;
+	else
+		ret = i2c->state;
+
+	/*
+	 * If this is the last message to be transfered (stop == 1)
+	 * Then check if the bus can be brought back to idle.
+	 */
+	if (ret == 0 && stop)
+		ret = exynos5_i2c_wait_bus_idle(i2c);
+
+	if (ret < 0) {
+		exynos5_i2c_reset(i2c);
+		if (ret == -ETIMEDOUT)
+			dev_warn(i2c->dev, "%s timeout\n",
+				 (msgs->flags & I2C_M_RD) ? "rx" : "tx");
+	}
+
+	/* Return the state as in interrupt routine */
+	return ret;
+}
+
+static int exynos5_i2c_xfer(struct i2c_adapter *adap,
+			struct i2c_msg *msgs, int num)
+{
+	struct exynos5_i2c *i2c = (struct exynos5_i2c *)adap->algo_data;
+	int i = 0, ret = 0, stop = 0;
+
+	if (i2c->suspended) {
+		dev_err(i2c->dev, "HS-I2C is not initialzed.\n");
+		return -EIO;
+	}
+
+	clk_prepare_enable(i2c->clk);
+
+	for (i = 0; i < num; i++, msgs++) {
+		stop = (i == num - 1);
+
+		ret = exynos5_i2c_xfer_msg(i2c, msgs, stop);
+
+		if (ret < 0)
+			goto out;
+	}
+
+	if (i == num) {
+		ret = num;
+	} else {
+		/* Only one message, cannot access the device */
+		if (i == 1)
+			ret = -EREMOTEIO;
+		else
+			ret = i;
+
+		dev_warn(i2c->dev, "xfer message failed\n");
+	}
+
+ out:
+	clk_disable_unprepare(i2c->clk);
+	return ret;
+}
+
+static u32 exynos5_i2c_func(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
+}
+
+static const struct i2c_algorithm exynos5_i2c_algorithm = {
+	.master_xfer		= exynos5_i2c_xfer,
+	.functionality		= exynos5_i2c_func,
+};
+
+static int exynos5_i2c_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct exynos5_i2c *i2c;
+	struct resource *mem;
+	unsigned int op_clock;
+	int ret;
+
+	i2c = devm_kzalloc(&pdev->dev, sizeof(struct exynos5_i2c), GFP_KERNEL);
+	if (!i2c) {
+		dev_err(&pdev->dev, "no memory for state\n");
+		return -ENOMEM;
+	}
+
+	if (of_property_read_u32(np, "clock-frequency", &op_clock)) {
+		i2c->speed_mode = HSI2C_FAST_SPD;
+		i2c->fs_clock = HSI2C_FS_TX_CLOCK;
+	} else {
+		if (op_clock >= HSI2C_HS_TX_CLOCK) {
+			i2c->speed_mode = HSI2C_HIGH_SPD;
+			i2c->fs_clock = HSI2C_FS_TX_CLOCK;
+			i2c->hs_clock = op_clock;
+		} else {
+			i2c->speed_mode = HSI2C_FAST_SPD;
+			i2c->fs_clock = op_clock;
+		}
+	}
+
+	strlcpy(i2c->adap.name, "exynos5-i2c", sizeof(i2c->adap.name));
+	i2c->adap.owner   = THIS_MODULE;
+	i2c->adap.algo    = &exynos5_i2c_algorithm;
+	i2c->adap.retries = 3;
+
+	i2c->dev = &pdev->dev;
+	i2c->clk = devm_clk_get(&pdev->dev, "hsi2c");
+	if (IS_ERR(i2c->clk)) {
+		dev_err(&pdev->dev, "cannot get clock\n");
+		return -ENOENT;
+	}
+
+	clk_prepare_enable(i2c->clk);
+
+	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	i2c->regs = devm_ioremap_resource(&pdev->dev, mem);
+	if (IS_ERR(i2c->regs)) {
+		ret = PTR_ERR(i2c->regs);
+		goto err_clk;
+	}
+
+	i2c->adap.dev.of_node = np;
+	i2c->adap.algo_data = i2c;
+	i2c->adap.dev.parent = &pdev->dev;
+
+	/* Clear pending interrupts from u-boot or misc causes */
+	exynos5_i2c_clr_pend_irq(i2c);
+
+	spin_lock_init(&i2c->lock);
+	init_completion(&i2c->msg_complete);
+
+	i2c->irq = ret = platform_get_irq(pdev, 0);
+	if (ret <= 0) {
+		dev_err(&pdev->dev, "cannot find HS-I2C IRQ\n");
+		ret = -EINVAL;
+		goto err_clk;
+	}
+
+	ret = devm_request_irq(&pdev->dev, i2c->irq, exynos5_i2c_irq,
+				IRQF_NO_SUSPEND | IRQF_ONESHOT,
+				dev_name(&pdev->dev), i2c);
+
+	if (ret != 0) {
+		dev_err(&pdev->dev, "cannot request HS-I2C IRQ %d\n", i2c->irq);
+		goto err_clk;
+	}
+
+	ret = exynos5_hsi2c_clock_setup(i2c);
+	if (ret)
+		goto err_clk;
+
+	exynos5_i2c_init(i2c);
+
+	ret = i2c_add_adapter(&i2c->adap);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "failed to add bus to i2c core\n");
+		goto err_clk;
+	}
+
+	platform_set_drvdata(pdev, i2c);
+
+ err_clk:
+	clk_disable_unprepare(i2c->clk);
+	return ret;
+}
+
+static int exynos5_i2c_remove(struct platform_device *pdev)
+{
+	struct exynos5_i2c *i2c = platform_get_drvdata(pdev);
+
+	i2c_del_adapter(&i2c->adap);
+
+	return 0;
+}
+
+static int exynos5_i2c_suspend_noirq(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct exynos5_i2c *i2c = platform_get_drvdata(pdev);
+
+	i2c->suspended = 1;
+
+	return 0;
+}
+
+static int exynos5_i2c_resume_noirq(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct exynos5_i2c *i2c = platform_get_drvdata(pdev);
+	int ret = 0;
+
+	clk_prepare_enable(i2c->clk);
+
+	ret = exynos5_hsi2c_clock_setup(i2c);
+	if (ret) {
+		clk_disable_unprepare(i2c->clk);
+		return ret;
+	}
+
+	exynos5_i2c_init(i2c);
+	clk_disable_unprepare(i2c->clk);
+	i2c->suspended = 0;
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(exynos5_i2c_dev_pm_ops, exynos5_i2c_suspend_noirq,
+			 exynos5_i2c_resume_noirq);
+
+static struct platform_driver exynos5_i2c_driver = {
+	.probe		= exynos5_i2c_probe,
+	.remove		= exynos5_i2c_remove,
+	.driver		= {
+		.owner	= THIS_MODULE,
+		.name	= "exynos5-hsi2c",
+		.pm	= &exynos5_i2c_dev_pm_ops,
+		.of_match_table = exynos5_i2c_match,
+	},
+};
+
+module_platform_driver(exynos5_i2c_driver);
+
+MODULE_DESCRIPTION("Exynos5 HS-I2C Bus driver");
+MODULE_AUTHOR("Naveen Krishna Chatradhi, <ch.naveen@samsung.com>");
+MODULE_AUTHOR("Taekgyun Ko, <taeggyun.ko@samsung.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c
index bfa02c6c2dda..d9f7e186a4c7 100644
--- a/drivers/i2c/busses/i2c-gpio.c
+++ b/drivers/i2c/busses/i2c-gpio.c
@@ -15,6 +15,7 @@
 #include <linux/slab.h>
 #include <linux/platform_device.h>
 #include <linux/gpio.h>
+#include <linux/of.h>
 #include <linux/of_gpio.h>
 
 struct i2c_gpio_private_data {
diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
index 4296d1721272..737e29866887 100644
--- a/drivers/i2c/busses/i2c-i801.c
+++ b/drivers/i2c/busses/i2c-i801.c
@@ -59,6 +59,7 @@
   Wellsburg (PCH) MS    0x8d7e     32     hard     yes     yes     yes
   Wellsburg (PCH) MS    0x8d7f     32     hard     yes     yes     yes
   Coleto Creek (PCH)    0x23b0     32     hard     yes     yes     yes
+  Wildcat Point-LP (PCH)   0x9ca2     32     hard     yes     yes     yes
 
   Features supported by this driver:
   Software PEC                     no
@@ -177,6 +178,7 @@
 #define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS1	0x8d7e
 #define PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS2	0x8d7f
 #define PCI_DEVICE_ID_INTEL_LYNXPOINT_LP_SMBUS	0x9c22
+#define PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS	0x9ca2
 
 struct i801_mux_config {
 	char *gpio_chip;
@@ -819,6 +821,7 @@ static DEFINE_PCI_DEVICE_TABLE(i801_ids) = {
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS1) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WELLSBURG_SMBUS_MS2) },
 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_COLETOCREEK_SMBUS) },
+	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_WILDCATPOINT_LP_SMBUS) },
 	{ 0, }
 };
 
diff --git a/drivers/i2c/busses/i2c-mv64xxx.c b/drivers/i2c/busses/i2c-mv64xxx.c
index d3e9cc3153a9..8be7e42aa4de 100644
--- a/drivers/i2c/busses/i2c-mv64xxx.c
+++ b/drivers/i2c/busses/i2c-mv64xxx.c
@@ -911,7 +911,7 @@ static struct platform_driver mv64xxx_i2c_driver = {
 	.driver	= {
 		.owner	= THIS_MODULE,
 		.name	= MV64XXX_I2C_CTLR_NAME,
-		.of_match_table = of_match_ptr(mv64xxx_i2c_of_match_table),
+		.of_match_table = mv64xxx_i2c_of_match_table,
 	},
 };
 
diff --git a/drivers/i2c/busses/i2c-mxs.c b/drivers/i2c/busses/i2c-mxs.c
index 3aedd86a6468..0cde4e6ab2b2 100644
--- a/drivers/i2c/busses/i2c-mxs.c
+++ b/drivers/i2c/busses/i2c-mxs.c
@@ -1,6 +1,7 @@
 /*
  * Freescale MXS I2C bus driver
  *
+ * Copyright (C) 2012-2013 Marek Vasut <marex@denx.de>
  * Copyright (C) 2011-2012 Wolfram Sang, Pengutronix e.K.
  *
  * based on a (non-working) driver which was:
@@ -34,10 +35,12 @@
 
 #define MXS_I2C_CTRL0		(0x00)
 #define MXS_I2C_CTRL0_SET	(0x04)
+#define MXS_I2C_CTRL0_CLR	(0x08)
 
 #define MXS_I2C_CTRL0_SFTRST			0x80000000
 #define MXS_I2C_CTRL0_RUN			0x20000000
 #define MXS_I2C_CTRL0_SEND_NAK_ON_LAST		0x02000000
+#define MXS_I2C_CTRL0_PIO_MODE			0x01000000
 #define MXS_I2C_CTRL0_RETAIN_CLOCK		0x00200000
 #define MXS_I2C_CTRL0_POST_SEND_STOP		0x00100000
 #define MXS_I2C_CTRL0_PRE_SEND_START		0x00080000
@@ -64,13 +67,13 @@
 #define MXS_I2C_CTRL1_SLAVE_IRQ			0x01
 
 #define MXS_I2C_STAT		(0x50)
+#define MXS_I2C_STAT_GOT_A_NAK			0x10000000
 #define MXS_I2C_STAT_BUS_BUSY			0x00000800
 #define MXS_I2C_STAT_CLK_GEN_BUSY		0x00000400
 
-#define MXS_I2C_DATA		(0xa0)
+#define MXS_I2C_DATA(i2c)	((i2c->dev_type == MXS_I2C_V1) ? 0x60 : 0xa0)
 
-#define MXS_I2C_DEBUG0		(0xb0)
-#define MXS_I2C_DEBUG0_CLR	(0xb8)
+#define MXS_I2C_DEBUG0_CLR(i2c)	((i2c->dev_type == MXS_I2C_V1) ? 0x78 : 0xb8)
 
 #define MXS_I2C_DEBUG0_DMAREQ	0x80000000
 
@@ -95,10 +98,17 @@
 #define MXS_CMD_I2C_READ	(MXS_I2C_CTRL0_SEND_NAK_ON_LAST | \
 				 MXS_I2C_CTRL0_MASTER_MODE)
 
+enum mxs_i2c_devtype {
+	MXS_I2C_UNKNOWN = 0,
+	MXS_I2C_V1,
+	MXS_I2C_V2,
+};
+
 /**
  * struct mxs_i2c_dev - per device, private MXS-I2C data
  *
  * @dev: driver model device node
+ * @dev_type: distinguish i.MX23/i.MX28 features
  * @regs: IO registers pointer
  * @cmd_complete: completion object for transaction wait
  * @cmd_err: error code for last transaction
@@ -106,6 +116,7 @@
  */
 struct mxs_i2c_dev {
 	struct device *dev;
+	enum mxs_i2c_devtype dev_type;
 	void __iomem *regs;
 	struct completion cmd_complete;
 	int cmd_err;
@@ -291,48 +302,11 @@ write_init_pio_fail:
 	return -EINVAL;
 }
 
-static int mxs_i2c_pio_wait_dmareq(struct mxs_i2c_dev *i2c)
+static int mxs_i2c_pio_wait_xfer_end(struct mxs_i2c_dev *i2c)
 {
 	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
 
-	while (!(readl(i2c->regs + MXS_I2C_DEBUG0) &
-		MXS_I2C_DEBUG0_DMAREQ)) {
-		if (time_after(jiffies, timeout))
-			return -ETIMEDOUT;
-		cond_resched();
-	}
-
-	return 0;
-}
-
-static int mxs_i2c_pio_wait_cplt(struct mxs_i2c_dev *i2c, int last)
-{
-	unsigned long timeout = jiffies + msecs_to_jiffies(1000);
-
-	/*
-	 * We do not use interrupts in the PIO mode. Due to the
-	 * maximum transfer length being 8 bytes in PIO mode, the
-	 * overhead of interrupt would be too large and this would
-	 * neglect the gain from using the PIO mode.
-	 */
-
-	while (!(readl(i2c->regs + MXS_I2C_CTRL1) &
-		MXS_I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ)) {
-		if (time_after(jiffies, timeout))
-			return -ETIMEDOUT;
-		cond_resched();
-	}
-
-	writel(MXS_I2C_CTRL1_DATA_ENGINE_CMPLT_IRQ,
-		i2c->regs + MXS_I2C_CTRL1_CLR);
-
-	/*
-	 * When ending a transfer with a stop, we have to wait for the bus to
-	 * go idle before we report the transfer as completed. Otherwise the
-	 * start of the next transfer may race with the end of the current one.
-	 */
-	while (last && (readl(i2c->regs + MXS_I2C_STAT) &
-			(MXS_I2C_STAT_BUS_BUSY | MXS_I2C_STAT_CLK_GEN_BUSY))) {
+	while (readl(i2c->regs + MXS_I2C_CTRL0) & MXS_I2C_CTRL0_RUN) {
 		if (time_after(jiffies, timeout))
 			return -ETIMEDOUT;
 		cond_resched();
@@ -370,106 +344,215 @@ static void mxs_i2c_pio_trigger_cmd(struct mxs_i2c_dev *i2c, u32 cmd)
 	writel(reg, i2c->regs + MXS_I2C_CTRL0);
 }
 
+/*
+ * Start WRITE transaction on the I2C bus. By studying i.MX23 datasheet,
+ * CTRL0::PIO_MODE bit description clarifies the order in which the registers
+ * must be written during PIO mode operation. First, the CTRL0 register has
+ * to be programmed with all the necessary bits but the RUN bit. Then the
+ * payload has to be written into the DATA register. Finally, the transmission
+ * is executed by setting the RUN bit in CTRL0.
+ */
+static void mxs_i2c_pio_trigger_write_cmd(struct mxs_i2c_dev *i2c, u32 cmd,
+					  u32 data)
+{
+	writel(cmd, i2c->regs + MXS_I2C_CTRL0);
+
+	if (i2c->dev_type == MXS_I2C_V1)
+		writel(MXS_I2C_CTRL0_PIO_MODE, i2c->regs + MXS_I2C_CTRL0_SET);
+
+	writel(data, i2c->regs + MXS_I2C_DATA(i2c));
+	writel(MXS_I2C_CTRL0_RUN, i2c->regs + MXS_I2C_CTRL0_SET);
+}
+
 static int mxs_i2c_pio_setup_xfer(struct i2c_adapter *adap,
 			struct i2c_msg *msg, uint32_t flags)
 {
 	struct mxs_i2c_dev *i2c = i2c_get_adapdata(adap);
 	uint32_t addr_data = msg->addr << 1;
 	uint32_t data = 0;
-	int i, shifts_left, ret;
+	int i, ret, xlen = 0, xmit = 0;
+	uint32_t start;
 
 	/* Mute IRQs coming from this block. */
 	writel(MXS_I2C_IRQ_MASK << 8, i2c->regs + MXS_I2C_CTRL1_CLR);
 
+	/*
+	 * MX23 idea:
+	 * - Enable CTRL0::PIO_MODE (1 << 24)
+	 * - Enable CTRL1::ACK_MODE (1 << 27)
+	 *
+	 * WARNING! The MX23 is broken in some way, even if it claims
+	 * to support PIO, when we try to transfer any amount of data
+	 * that is not aligned to 4 bytes, the DMA engine will have
+	 * bits in DEBUG1::DMA_BYTES_ENABLES still set even after the
+	 * transfer. This in turn will mess up the next transfer as
+	 * the block it emit one byte write onto the bus terminated
+	 * with a NAK+STOP. A possible workaround is to reset the IP
+	 * block after every PIO transmission, which might just work.
+	 *
+	 * NOTE: The CTRL0::PIO_MODE description is important, since
+	 * it outlines how the PIO mode is really supposed to work.
+	 */
 	if (msg->flags & I2C_M_RD) {
+		/*
+		 * PIO READ transfer:
+		 *
+		 * This transfer MUST be limited to 4 bytes maximum. It is not
+		 * possible to transfer more than four bytes via PIO, since we
+		 * can not in any way make sure we can read the data from the
+		 * DATA register fast enough. Besides, the RX FIFO is only four
+		 * bytes deep, thus we can only really read up to four bytes at
+		 * time. Finally, there is no bit indicating us that new data
+		 * arrived at the FIFO and can thus be fetched from the DATA
+		 * register.
+		 */
+		BUG_ON(msg->len > 4);
+
 		addr_data |= I2C_SMBUS_READ;
 
 		/* SELECT command. */
-		mxs_i2c_pio_trigger_cmd(i2c, MXS_CMD_I2C_SELECT);
-
-		ret = mxs_i2c_pio_wait_dmareq(i2c);
-		if (ret)
-			return ret;
-
-		writel(addr_data, i2c->regs + MXS_I2C_DATA);
-		writel(MXS_I2C_DEBUG0_DMAREQ, i2c->regs + MXS_I2C_DEBUG0_CLR);
+		mxs_i2c_pio_trigger_write_cmd(i2c, MXS_CMD_I2C_SELECT,
+					      addr_data);
 
-		ret = mxs_i2c_pio_wait_cplt(i2c, 0);
-		if (ret)
-			return ret;
-
-		if (mxs_i2c_pio_check_error_state(i2c))
+		ret = mxs_i2c_pio_wait_xfer_end(i2c);
+		if (ret) {
+			dev_err(i2c->dev,
+				"PIO: Failed to send SELECT command!\n");
 			goto cleanup;
+		}
 
 		/* READ command. */
 		mxs_i2c_pio_trigger_cmd(i2c,
 					MXS_CMD_I2C_READ | flags |
 					MXS_I2C_CTRL0_XFER_COUNT(msg->len));
 
+		ret = mxs_i2c_pio_wait_xfer_end(i2c);
+		if (ret) {
+			dev_err(i2c->dev,
+				"PIO: Failed to send SELECT command!\n");
+			goto cleanup;
+		}
+
+		data = readl(i2c->regs + MXS_I2C_DATA(i2c));
 		for (i = 0; i < msg->len; i++) {
-			if ((i & 3) == 0) {
-				ret = mxs_i2c_pio_wait_dmareq(i2c);
-				if (ret)
-					return ret;
-				data = readl(i2c->regs + MXS_I2C_DATA);
-				writel(MXS_I2C_DEBUG0_DMAREQ,
-				       i2c->regs + MXS_I2C_DEBUG0_CLR);
-			}
 			msg->buf[i] = data & 0xff;
 			data >>= 8;
 		}
 	} else {
+		/*
+		 * PIO WRITE transfer:
+		 *
+		 * The code below implements clock stretching to circumvent
+		 * the possibility of kernel not being able to supply data
+		 * fast enough. It is possible to transfer arbitrary amount
+		 * of data using PIO write.
+		 */
 		addr_data |= I2C_SMBUS_WRITE;
 
-		/* WRITE command. */
-		mxs_i2c_pio_trigger_cmd(i2c,
-					MXS_CMD_I2C_WRITE | flags |
-					MXS_I2C_CTRL0_XFER_COUNT(msg->len + 1));
-
 		/*
 		 * The LSB of data buffer is the first byte blasted across
 		 * the bus. Higher order bytes follow. Thus the following
 		 * filling schematic.
 		 */
+
 		data = addr_data << 24;
+
+		/* Start the transfer with START condition. */
+		start = MXS_I2C_CTRL0_PRE_SEND_START;
+
+		/* If the transfer is long, use clock stretching. */
+		if (msg->len > 3)
+			start |= MXS_I2C_CTRL0_RETAIN_CLOCK;
+
 		for (i = 0; i < msg->len; i++) {
 			data >>= 8;
 			data |= (msg->buf[i] << 24);
-			if ((i & 3) == 2) {
-				ret = mxs_i2c_pio_wait_dmareq(i2c);
-				if (ret)
-					return ret;
-				writel(data, i2c->regs + MXS_I2C_DATA);
-				writel(MXS_I2C_DEBUG0_DMAREQ,
-				       i2c->regs + MXS_I2C_DEBUG0_CLR);
+
+			xmit = 0;
+
+			/* This is the last transfer of the message. */
+			if (i + 1 == msg->len) {
+				/* Add optional STOP flag. */
+				start |= flags;
+				/* Remove RETAIN_CLOCK bit. */
+				start &= ~MXS_I2C_CTRL0_RETAIN_CLOCK;
+				xmit = 1;
 			}
-		}
 
-		shifts_left = 24 - (i & 3) * 8;
-		if (shifts_left) {
-			data >>= shifts_left;
-			ret = mxs_i2c_pio_wait_dmareq(i2c);
-			if (ret)
-				return ret;
-			writel(data, i2c->regs + MXS_I2C_DATA);
+			/* Four bytes are ready in the "data" variable. */
+			if ((i & 3) == 2)
+				xmit = 1;
+
+			/* Nothing interesting happened, continue stuffing. */
+			if (!xmit)
+				continue;
+
+			/*
+			 * Compute the size of the transfer and shift the
+			 * data accordingly.
+			 *
+			 * i = (4k + 0) .... xlen = 2
+			 * i = (4k + 1) .... xlen = 3
+			 * i = (4k + 2) .... xlen = 4
+			 * i = (4k + 3) .... xlen = 1
+			 */
+
+			if ((i % 4) == 3)
+				xlen = 1;
+			else
+				xlen = (i % 4) + 2;
+
+			data >>= (4 - xlen) * 8;
+
+			dev_dbg(i2c->dev,
+				"PIO: len=%i pos=%i total=%i [W%s%s%s]\n",
+				xlen, i, msg->len,
+				start & MXS_I2C_CTRL0_PRE_SEND_START ? "S" : "",
+				start & MXS_I2C_CTRL0_POST_SEND_STOP ? "E" : "",
+				start & MXS_I2C_CTRL0_RETAIN_CLOCK ? "C" : "");
+
 			writel(MXS_I2C_DEBUG0_DMAREQ,
-			       i2c->regs + MXS_I2C_DEBUG0_CLR);
+			       i2c->regs + MXS_I2C_DEBUG0_CLR(i2c));
+
+			mxs_i2c_pio_trigger_write_cmd(i2c,
+				start | MXS_I2C_CTRL0_MASTER_MODE |
+				MXS_I2C_CTRL0_DIRECTION |
+				MXS_I2C_CTRL0_XFER_COUNT(xlen), data);
+
+			/* The START condition is sent only once. */
+			start &= ~MXS_I2C_CTRL0_PRE_SEND_START;
+
+			/* Wait for the end of the transfer. */
+			ret = mxs_i2c_pio_wait_xfer_end(i2c);
+			if (ret) {
+				dev_err(i2c->dev,
+					"PIO: Failed to finish WRITE cmd!\n");
+				break;
+			}
+
+			/* Check NAK here. */
+			ret = readl(i2c->regs + MXS_I2C_STAT) &
+				    MXS_I2C_STAT_GOT_A_NAK;
+			if (ret) {
+				ret = -ENXIO;
+				goto cleanup;
+			}
 		}
 	}
 
-	ret = mxs_i2c_pio_wait_cplt(i2c, flags & MXS_I2C_CTRL0_POST_SEND_STOP);
-	if (ret)
-		return ret;
-
 	/* make sure we capture any occurred error into cmd_err */
-	mxs_i2c_pio_check_error_state(i2c);
+	ret = mxs_i2c_pio_check_error_state(i2c);
 
 cleanup:
 	/* Clear any dangling IRQs and re-enable interrupts. */
 	writel(MXS_I2C_IRQ_MASK, i2c->regs + MXS_I2C_CTRL1_CLR);
 	writel(MXS_I2C_IRQ_MASK << 8, i2c->regs + MXS_I2C_CTRL1_SET);
 
-	return 0;
+	/* Clear the PIO_MODE on i.MX23 */
+	if (i2c->dev_type == MXS_I2C_V1)
+		writel(MXS_I2C_CTRL0_PIO_MODE, i2c->regs + MXS_I2C_CTRL0_CLR);
+
+	return ret;
 }
 
 /*
@@ -479,8 +562,9 @@ static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg,
 				int stop)
 {
 	struct mxs_i2c_dev *i2c = i2c_get_adapdata(adap);
-	int ret, err;
+	int ret;
 	int flags;
+	int use_pio = 0;
 
 	flags = stop ? MXS_I2C_CTRL0_POST_SEND_STOP : 0;
 
@@ -491,19 +575,21 @@ static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg,
 		return -EINVAL;
 
 	/*
-	 * The current boundary to select between PIO/DMA transfer method
-	 * is set to 8 bytes, transfers shorter than 8 bytes are transfered
-	 * using PIO mode while longer transfers use DMA. The 8 byte border is
-	 * based on this empirical measurement and a lot of previous frobbing.
+	 * The MX28 I2C IP block can only do PIO READ for transfer of to up
+	 * 4 bytes of length. The write transfer is not limited as it can use
+	 * clock stretching to avoid FIFO underruns.
 	 */
+	if ((msg->flags & I2C_M_RD) && (msg->len <= 4))
+		use_pio = 1;
+	if (!(msg->flags & I2C_M_RD) && (msg->len < 7))
+		use_pio = 1;
+
 	i2c->cmd_err = 0;
-	if (0) {	/* disable PIO mode until a proper fix is made */
+	if (use_pio) {
 		ret = mxs_i2c_pio_setup_xfer(adap, msg, flags);
-		if (ret) {
-			err = mxs_i2c_reset(i2c);
-			if (err)
-				return err;
-		}
+		/* No need to reset the block if NAK was received. */
+		if (ret && (ret != -ENXIO))
+			mxs_i2c_reset(i2c);
 	} else {
 		reinit_completion(&i2c->cmd_complete);
 		ret = mxs_i2c_dma_setup_xfer(adap, msg, flags);
@@ -514,9 +600,11 @@ static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg,
 						msecs_to_jiffies(1000));
 		if (ret == 0)
 			goto timeout;
+
+		ret = i2c->cmd_err;
 	}
 
-	if (i2c->cmd_err == -ENXIO) {
+	if (ret == -ENXIO) {
 		/*
 		 * If the transfer fails with a NAK from the slave the
 		 * controller halts until it gets told to return to idle state.
@@ -525,7 +613,19 @@ static int mxs_i2c_xfer_msg(struct i2c_adapter *adap, struct i2c_msg *msg,
 		       i2c->regs + MXS_I2C_CTRL1_SET);
 	}
 
-	ret = i2c->cmd_err;
+	/*
+	 * WARNING!
+	 * The i.MX23 is strange. After each and every operation, it's I2C IP
+	 * block must be reset, otherwise the IP block will misbehave. This can
+	 * be observed on the bus by the block sending out one single byte onto
+	 * the bus. In case such an error happens, bit 27 will be set in the
+	 * DEBUG0 register. This bit is not documented in the i.MX23 datasheet
+	 * and is marked as "TBD" instead. To reset this bit to a correct state,
+	 * reset the whole block. Since the block reset does not take long, do
+	 * reset the block after every transfer to play safe.
+	 */
+	if (i2c->dev_type == MXS_I2C_V1)
+		mxs_i2c_reset(i2c);
 
 	dev_dbg(i2c->dev, "Done with err=%d\n", ret);
 
@@ -680,8 +780,28 @@ static int mxs_i2c_get_ofdata(struct mxs_i2c_dev *i2c)
 	return 0;
 }
 
+static struct platform_device_id mxs_i2c_devtype[] = {
+	{
+		.name = "imx23-i2c",
+		.driver_data = MXS_I2C_V1,
+	}, {
+		.name = "imx28-i2c",
+		.driver_data = MXS_I2C_V2,
+	}, { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(platform, mxs_i2c_devtype);
+
+static const struct of_device_id mxs_i2c_dt_ids[] = {
+	{ .compatible = "fsl,imx23-i2c", .data = &mxs_i2c_devtype[0], },
+	{ .compatible = "fsl,imx28-i2c", .data = &mxs_i2c_devtype[1], },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mxs_i2c_dt_ids);
+
 static int mxs_i2c_probe(struct platform_device *pdev)
 {
+	const struct of_device_id *of_id =
+				of_match_device(mxs_i2c_dt_ids, &pdev->dev);
 	struct device *dev = &pdev->dev;
 	struct mxs_i2c_dev *i2c;
 	struct i2c_adapter *adap;
@@ -693,6 +813,11 @@ static int mxs_i2c_probe(struct platform_device *pdev)
 	if (!i2c)
 		return -ENOMEM;
 
+	if (of_id) {
+		const struct platform_device_id *device_id = of_id->data;
+		i2c->dev_type = device_id->driver_data;
+	}
+
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	irq = platform_get_irq(pdev, 0);
 
@@ -768,12 +893,6 @@ static int mxs_i2c_remove(struct platform_device *pdev)
 	return 0;
 }
 
-static const struct of_device_id mxs_i2c_dt_ids[] = {
-	{ .compatible = "fsl,imx28-i2c", },
-	{ /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, mxs_i2c_dt_ids);
-
 static struct platform_driver mxs_i2c_driver = {
 	.driver = {
 		   .name = DRIVER_NAME,
@@ -796,6 +915,7 @@ static void __exit mxs_i2c_exit(void)
 }
 module_exit(mxs_i2c_exit);
 
+MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
 MODULE_AUTHOR("Wolfram Sang <w.sang@pengutronix.de>");
 MODULE_DESCRIPTION("MXS I2C Bus Driver");
 MODULE_LICENSE("GPL");
diff --git a/drivers/i2c/busses/i2c-pnx.c b/drivers/i2c/busses/i2c-pnx.c
index 1a9ea25f2314..c9a352f0a9a5 100644
--- a/drivers/i2c/busses/i2c-pnx.c
+++ b/drivers/i2c/busses/i2c-pnx.c
@@ -23,6 +23,7 @@
 #include <linux/err.h>
 #include <linux/clk.h>
 #include <linux/slab.h>
+#include <linux/of.h>
 
 #define I2C_PNX_TIMEOUT_DEFAULT		10 /* msec */
 #define I2C_PNX_SPEED_KHZ_DEFAULT	100
diff --git a/drivers/i2c/busses/i2c-rcar.c b/drivers/i2c/busses/i2c-rcar.c
index d2fe11da5e82..2c2fd7c2b116 100644
--- a/drivers/i2c/busses/i2c-rcar.c
+++ b/drivers/i2c/busses/i2c-rcar.c
@@ -33,6 +33,7 @@
 #include <linux/i2c/i2c-rcar.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/pm_runtime.h>
 #include <linux/slab.h>
@@ -102,8 +103,8 @@ enum {
 #define ID_NACK		(1 << 4)
 
 enum rcar_i2c_type {
-	I2C_RCAR_H1,
-	I2C_RCAR_H2,
+	I2C_RCAR_GEN1,
+	I2C_RCAR_GEN2,
 };
 
 struct rcar_i2c_priv {
@@ -226,22 +227,23 @@ static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv,
 				    u32 bus_speed,
 				    struct device *dev)
 {
-	struct clk *clkp = clk_get(NULL, "peripheral_clk");
+	struct clk *clkp = clk_get(dev, NULL);
 	u32 scgd, cdf;
 	u32 round, ick;
 	u32 scl;
 	u32 cdf_width;
+	unsigned long rate;
 
-	if (!clkp) {
-		dev_err(dev, "there is no peripheral_clk\n");
-		return -EIO;
+	if (IS_ERR(clkp)) {
+		dev_err(dev, "couldn't get clock\n");
+		return PTR_ERR(clkp);
 	}
 
 	switch (priv->devtype) {
-	case I2C_RCAR_H1:
+	case I2C_RCAR_GEN1:
 		cdf_width = 2;
 		break;
-	case I2C_RCAR_H2:
+	case I2C_RCAR_GEN2:
 		cdf_width = 3;
 		break;
 	default:
@@ -264,15 +266,14 @@ static int rcar_i2c_clock_calculate(struct rcar_i2c_priv *priv,
 	 * clkp : peripheral_clk
 	 * F[]  : integer up-valuation
 	 */
-	for (cdf = 0; cdf < (1 << cdf_width); cdf++) {
-		ick = clk_get_rate(clkp) / (1 + cdf);
-		if (ick < 20000000)
-			goto ick_find;
+	rate = clk_get_rate(clkp);
+	cdf = rate / 20000000;
+	if (cdf >= 1 << cdf_width) {
+		dev_err(dev, "Input clock %lu too high\n", rate);
+		return -EIO;
 	}
-	dev_err(dev, "there is no best CDF\n");
-	return -EIO;
+	ick = rate / (cdf + 1);
 
-ick_find:
 	/*
 	 * it is impossible to calculate large scale
 	 * number on u32. separate it
@@ -290,6 +291,12 @@ ick_find:
 	 *
 	 * Calculation result (= SCL) should be less than
 	 * bus_speed for hardware safety
+	 *
+	 * We could use something along the lines of
+	 *	div = ick / (bus_speed + 1) + 1;
+	 *	scgd = (div - 20 - round + 7) / 8;
+	 *	scl = ick / (20 + (scgd * 8) + round);
+	 * (not fully verified) but that would get pretty involved
 	 */
 	for (scgd = 0; scgd < 0x40; scgd++) {
 		scl = ick / (20 + (scgd * 8) + round);
@@ -306,7 +313,7 @@ scgd_find:
 	/*
 	 * keep icccr value
 	 */
-	priv->icccr = (scgd << (cdf_width) | cdf);
+	priv->icccr = scgd << cdf_width | cdf;
 
 	return 0;
 }
@@ -632,6 +639,15 @@ static const struct i2c_algorithm rcar_i2c_algo = {
 	.functionality	= rcar_i2c_func,
 };
 
+static const struct of_device_id rcar_i2c_dt_ids[] = {
+	{ .compatible = "renesas,i2c-rcar", .data = (void *)I2C_RCAR_GEN1 },
+	{ .compatible = "renesas,i2c-r8a7778", .data = (void *)I2C_RCAR_GEN1 },
+	{ .compatible = "renesas,i2c-r8a7779", .data = (void *)I2C_RCAR_GEN1 },
+	{ .compatible = "renesas,i2c-r8a7790", .data = (void *)I2C_RCAR_GEN2 },
+	{},
+};
+MODULE_DEVICE_TABLE(of, rcar_i2c_dt_ids);
+
 static int rcar_i2c_probe(struct platform_device *pdev)
 {
 	struct i2c_rcar_platform_data *pdata = dev_get_platdata(&pdev->dev);
@@ -649,10 +665,15 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 	}
 
 	bus_speed = 100000; /* default 100 kHz */
-	if (pdata && pdata->bus_speed)
+	ret = of_property_read_u32(dev->of_node, "clock-frequency", &bus_speed);
+	if (ret < 0 && pdata && pdata->bus_speed)
 		bus_speed = pdata->bus_speed;
 
-	priv->devtype = platform_get_device_id(pdev)->driver_data;
+	if (pdev->dev.of_node)
+		priv->devtype = (long)of_match_device(rcar_i2c_dt_ids,
+						      dev)->data;
+	else
+		priv->devtype = platform_get_device_id(pdev)->driver_data;
 
 	ret = rcar_i2c_clock_calculate(priv, bus_speed, dev);
 	if (ret < 0)
@@ -673,6 +694,7 @@ static int rcar_i2c_probe(struct platform_device *pdev)
 	adap->class		= I2C_CLASS_HWMON | I2C_CLASS_SPD;
 	adap->retries		= 3;
 	adap->dev.parent	= dev;
+	adap->dev.of_node	= dev->of_node;
 	i2c_set_adapdata(adap, priv);
 	strlcpy(adap->name, pdev->name, sizeof(adap->name));
 
@@ -709,9 +731,9 @@ static int rcar_i2c_remove(struct platform_device *pdev)
 }
 
 static struct platform_device_id rcar_i2c_id_table[] = {
-	{ "i2c-rcar",		I2C_RCAR_H1 },
-	{ "i2c-rcar_h1",	I2C_RCAR_H1 },
-	{ "i2c-rcar_h2",	I2C_RCAR_H2 },
+	{ "i2c-rcar",		I2C_RCAR_GEN1 },
+	{ "i2c-rcar_gen1",	I2C_RCAR_GEN1 },
+	{ "i2c-rcar_gen2",	I2C_RCAR_GEN2 },
 	{},
 };
 MODULE_DEVICE_TABLE(platform, rcar_i2c_id_table);
@@ -720,6 +742,7 @@ static struct platform_driver rcar_i2c_driver = {
 	.driver	= {
 		.name	= "i2c-rcar",
 		.owner	= THIS_MODULE,
+		.of_match_table = rcar_i2c_dt_ids,
 	},
 	.probe		= rcar_i2c_probe,
 	.remove		= rcar_i2c_remove,
diff --git a/drivers/i2c/busses/i2c-s3c2410.c b/drivers/i2c/busses/i2c-s3c2410.c
index 3747b9bf67d6..bf8fb94ebc5d 100644
--- a/drivers/i2c/busses/i2c-s3c2410.c
+++ b/drivers/i2c/busses/i2c-s3c2410.c
@@ -36,6 +36,7 @@
 #include <linux/cpufreq.h>
 #include <linux/slab.h>
 #include <linux/io.h>
+#include <linux/of.h>
 #include <linux/of_gpio.h>
 #include <linux/pinctrl/consumer.h>
 
diff --git a/drivers/i2c/busses/i2c-scmi.c b/drivers/i2c/busses/i2c-scmi.c
index c447e8d40b78..599235514138 100644
--- a/drivers/i2c/busses/i2c-scmi.c
+++ b/drivers/i2c/busses/i2c-scmi.c
@@ -223,7 +223,7 @@ acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
 		goto out;
 
 	obj = pkg->package.elements + 1;
-	if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
+	if (obj->type != ACPI_TYPE_INTEGER) {
 		ACPI_ERROR((AE_INFO, "Invalid argument type"));
 		result = -EIO;
 		goto out;
@@ -235,7 +235,7 @@ acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
 	case I2C_SMBUS_BYTE:
 	case I2C_SMBUS_BYTE_DATA:
 	case I2C_SMBUS_WORD_DATA:
-		if (obj == NULL || obj->type != ACPI_TYPE_INTEGER) {
+		if (obj->type != ACPI_TYPE_INTEGER) {
 			ACPI_ERROR((AE_INFO, "Invalid argument type"));
 			result = -EIO;
 			goto out;
@@ -246,7 +246,7 @@ acpi_smbus_cmi_access(struct i2c_adapter *adap, u16 addr, unsigned short flags,
 			data->byte = obj->integer.value;
 		break;
 	case I2C_SMBUS_BLOCK_DATA:
-		if (obj == NULL || obj->type != ACPI_TYPE_BUFFER) {
+		if (obj->type != ACPI_TYPE_BUFFER) {
 			ACPI_ERROR((AE_INFO, "Invalid argument type"));
 			result = -EIO;
 			goto out;
diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
index 55110ddbed1f..1d79585ba4b3 100644
--- a/drivers/i2c/busses/i2c-sh_mobile.c
+++ b/drivers/i2c/busses/i2c-sh_mobile.c
@@ -235,7 +235,7 @@ static void sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd)
 	int offset;
 
 	/* Get clock rate after clock is enabled */
-	clk_enable(pd->clk);
+	clk_prepare_enable(pd->clk);
 	i2c_clk_khz = clk_get_rate(pd->clk) / 1000;
 	i2c_clk_khz /= pd->clks_per_count;
 
@@ -270,14 +270,14 @@ static void sh_mobile_i2c_init(struct sh_mobile_i2c_data *pd)
 		pd->icic &= ~ICIC_ICCHB8;
 
 out:
-	clk_disable(pd->clk);
+	clk_disable_unprepare(pd->clk);
 }
 
 static void activate_ch(struct sh_mobile_i2c_data *pd)
 {
 	/* Wake up device and enable clock */
 	pm_runtime_get_sync(pd->dev);
-	clk_enable(pd->clk);
+	clk_prepare_enable(pd->clk);
 
 	/* Enable channel and configure rx ack */
 	iic_set_clr(pd, ICCR, ICCR_ICE, 0);
@@ -300,7 +300,7 @@ static void deactivate_ch(struct sh_mobile_i2c_data *pd)
 	iic_set_clr(pd, ICCR, 0, ICCR_ICE);
 
 	/* Disable clock and mark device as idle */
-	clk_disable(pd->clk);
+	clk_disable_unprepare(pd->clk);
 	pm_runtime_put_sync(pd->dev);
 }
 
diff --git a/drivers/i2c/busses/i2c-st.c b/drivers/i2c/busses/i2c-st.c
new file mode 100644
index 000000000000..9cf715d69551
--- /dev/null
+++ b/drivers/i2c/busses/i2c-st.c
@@ -0,0 +1,872 @@
+/*
+ * Copyright (C) 2013 STMicroelectronics
+ *
+ * I2C master mode controller driver, used in STMicroelectronics devices.
+ *
+ * Author: Maxime Coquelin <maxime.coquelin@st.com>
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/i2c.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+/* SSC registers */
+#define SSC_BRG				0x000
+#define SSC_TBUF			0x004
+#define SSC_RBUF			0x008
+#define SSC_CTL				0x00C
+#define SSC_IEN				0x010
+#define SSC_STA				0x014
+#define SSC_I2C				0x018
+#define SSC_SLAD			0x01C
+#define SSC_REP_START_HOLD		0x020
+#define SSC_START_HOLD			0x024
+#define SSC_REP_START_SETUP		0x028
+#define SSC_DATA_SETUP			0x02C
+#define SSC_STOP_SETUP			0x030
+#define SSC_BUS_FREE			0x034
+#define SSC_TX_FSTAT			0x038
+#define SSC_RX_FSTAT			0x03C
+#define SSC_PRE_SCALER_BRG		0x040
+#define SSC_CLR				0x080
+#define SSC_NOISE_SUPP_WIDTH		0x100
+#define SSC_PRSCALER			0x104
+#define SSC_NOISE_SUPP_WIDTH_DATAOUT	0x108
+#define SSC_PRSCALER_DATAOUT		0x10c
+
+/* SSC Control */
+#define SSC_CTL_DATA_WIDTH_9		0x8
+#define SSC_CTL_DATA_WIDTH_MSK		0xf
+#define SSC_CTL_BM			0xf
+#define SSC_CTL_HB			BIT(4)
+#define SSC_CTL_PH			BIT(5)
+#define SSC_CTL_PO			BIT(6)
+#define SSC_CTL_SR			BIT(7)
+#define SSC_CTL_MS			BIT(8)
+#define SSC_CTL_EN			BIT(9)
+#define SSC_CTL_LPB			BIT(10)
+#define SSC_CTL_EN_TX_FIFO		BIT(11)
+#define SSC_CTL_EN_RX_FIFO		BIT(12)
+#define SSC_CTL_EN_CLST_RX		BIT(13)
+
+/* SSC Interrupt Enable */
+#define SSC_IEN_RIEN			BIT(0)
+#define SSC_IEN_TIEN			BIT(1)
+#define SSC_IEN_TEEN			BIT(2)
+#define SSC_IEN_REEN			BIT(3)
+#define SSC_IEN_PEEN			BIT(4)
+#define SSC_IEN_AASEN			BIT(6)
+#define SSC_IEN_STOPEN			BIT(7)
+#define SSC_IEN_ARBLEN			BIT(8)
+#define SSC_IEN_NACKEN			BIT(10)
+#define SSC_IEN_REPSTRTEN		BIT(11)
+#define SSC_IEN_TX_FIFO_HALF		BIT(12)
+#define SSC_IEN_RX_FIFO_HALF_FULL	BIT(14)
+
+/* SSC Status */
+#define SSC_STA_RIR			BIT(0)
+#define SSC_STA_TIR			BIT(1)
+#define SSC_STA_TE			BIT(2)
+#define SSC_STA_RE			BIT(3)
+#define SSC_STA_PE			BIT(4)
+#define SSC_STA_CLST			BIT(5)
+#define SSC_STA_AAS			BIT(6)
+#define SSC_STA_STOP			BIT(7)
+#define SSC_STA_ARBL			BIT(8)
+#define SSC_STA_BUSY			BIT(9)
+#define SSC_STA_NACK			BIT(10)
+#define SSC_STA_REPSTRT			BIT(11)
+#define SSC_STA_TX_FIFO_HALF		BIT(12)
+#define SSC_STA_TX_FIFO_FULL		BIT(13)
+#define SSC_STA_RX_FIFO_HALF		BIT(14)
+
+/* SSC I2C Control */
+#define SSC_I2C_I2CM			BIT(0)
+#define SSC_I2C_STRTG			BIT(1)
+#define SSC_I2C_STOPG			BIT(2)
+#define SSC_I2C_ACKG			BIT(3)
+#define SSC_I2C_AD10			BIT(4)
+#define SSC_I2C_TXENB			BIT(5)
+#define SSC_I2C_REPSTRTG		BIT(11)
+#define SSC_I2C_SLAVE_DISABLE		BIT(12)
+
+/* SSC Tx FIFO Status */
+#define SSC_TX_FSTAT_STATUS		0x07
+
+/* SSC Rx FIFO Status */
+#define SSC_RX_FSTAT_STATUS		0x07
+
+/* SSC Clear bit operation */
+#define SSC_CLR_SSCAAS			BIT(6)
+#define SSC_CLR_SSCSTOP			BIT(7)
+#define SSC_CLR_SSCARBL			BIT(8)
+#define SSC_CLR_NACK			BIT(10)
+#define SSC_CLR_REPSTRT			BIT(11)
+
+/* SSC Clock Prescaler */
+#define SSC_PRSC_VALUE			0x0f
+
+
+#define SSC_TXFIFO_SIZE			0x8
+#define SSC_RXFIFO_SIZE			0x8
+
+enum st_i2c_mode {
+	I2C_MODE_STANDARD,
+	I2C_MODE_FAST,
+	I2C_MODE_END,
+};
+
+/**
+ * struct st_i2c_timings - per-Mode tuning parameters
+ * @rate: I2C bus rate
+ * @rep_start_hold: I2C repeated start hold time requirement
+ * @rep_start_setup: I2C repeated start set up time requirement
+ * @start_hold: I2C start hold time requirement
+ * @data_setup_time: I2C data set up time requirement
+ * @stop_setup_time: I2C stop set up time requirement
+ * @bus_free_time: I2C bus free time requirement
+ * @sda_pulse_min_limit: I2C SDA pulse mini width limit
+ */
+struct st_i2c_timings {
+	u32 rate;
+	u32 rep_start_hold;
+	u32 rep_start_setup;
+	u32 start_hold;
+	u32 data_setup_time;
+	u32 stop_setup_time;
+	u32 bus_free_time;
+	u32 sda_pulse_min_limit;
+};
+
+/**
+ * struct st_i2c_client - client specific data
+ * @addr: 8-bit slave addr, including r/w bit
+ * @count: number of bytes to be transfered
+ * @xfered: number of bytes already transferred
+ * @buf: data buffer
+ * @result: result of the transfer
+ * @stop: last I2C msg to be sent, i.e. STOP to be generated
+ */
+struct st_i2c_client {
+	u8	addr;
+	u32	count;
+	u32	xfered;
+	u8	*buf;
+	int	result;
+	bool	stop;
+};
+
+/**
+ * struct st_i2c_dev - private data of the controller
+ * @adap: I2C adapter for this controller
+ * @dev: device for this controller
+ * @base: virtual memory area
+ * @complete: completion of I2C message
+ * @irq: interrupt line for th controller
+ * @clk: hw ssc block clock
+ * @mode: I2C mode of the controller. Standard or Fast only supported
+ * @scl_min_width_us: SCL line minimum pulse width in us
+ * @sda_min_width_us: SDA line minimum pulse width in us
+ * @client: I2C transfert information
+ * @busy: I2C transfer on-going
+ */
+struct st_i2c_dev {
+	struct i2c_adapter	adap;
+	struct device		*dev;
+	void __iomem		*base;
+	struct completion	complete;
+	int			irq;
+	struct clk		*clk;
+	int			mode;
+	u32			scl_min_width_us;
+	u32			sda_min_width_us;
+	struct st_i2c_client	client;
+	bool			busy;
+};
+
+static inline void st_i2c_set_bits(void __iomem *reg, u32 mask)
+{
+	writel_relaxed(readl_relaxed(reg) | mask, reg);
+}
+
+static inline void st_i2c_clr_bits(void __iomem *reg, u32 mask)
+{
+	writel_relaxed(readl_relaxed(reg) & ~mask, reg);
+}
+
+/* From I2C Specifications v0.5 */
+static struct st_i2c_timings i2c_timings[] = {
+	[I2C_MODE_STANDARD] = {
+		.rate			= 100000,
+		.rep_start_hold		= 4000,
+		.rep_start_setup	= 4700,
+		.start_hold		= 4000,
+		.data_setup_time	= 250,
+		.stop_setup_time	= 4000,
+		.bus_free_time		= 4700,
+	},
+	[I2C_MODE_FAST] = {
+		.rate			= 400000,
+		.rep_start_hold		= 600,
+		.rep_start_setup	= 600,
+		.start_hold		= 600,
+		.data_setup_time	= 100,
+		.stop_setup_time	= 600,
+		.bus_free_time		= 1300,
+	},
+};
+
+static void st_i2c_flush_rx_fifo(struct st_i2c_dev *i2c_dev)
+{
+	int count, i;
+
+	/*
+	 * Counter only counts up to 7 but fifo size is 8...
+	 * When fifo is full, counter is 0 and RIR bit of status register is
+	 * set
+	 */
+	if (readl_relaxed(i2c_dev->base + SSC_STA) & SSC_STA_RIR)
+		count = SSC_RXFIFO_SIZE;
+	else
+		count = readl_relaxed(i2c_dev->base + SSC_RX_FSTAT) &
+			SSC_RX_FSTAT_STATUS;
+
+	for (i = 0; i < count; i++)
+		readl_relaxed(i2c_dev->base + SSC_RBUF);
+}
+
+static void st_i2c_soft_reset(struct st_i2c_dev *i2c_dev)
+{
+	/*
+	 * FIFO needs to be emptied before reseting the IP,
+	 * else the controller raises a BUSY error.
+	 */
+	st_i2c_flush_rx_fifo(i2c_dev);
+
+	st_i2c_set_bits(i2c_dev->base + SSC_CTL, SSC_CTL_SR);
+	st_i2c_clr_bits(i2c_dev->base + SSC_CTL, SSC_CTL_SR);
+}
+
+/**
+ * st_i2c_hw_config() - Prepare SSC block, calculate and apply tuning timings
+ * @i2c_dev: Controller's private data
+ */
+static void st_i2c_hw_config(struct st_i2c_dev *i2c_dev)
+{
+	unsigned long rate;
+	u32 val, ns_per_clk;
+	struct st_i2c_timings *t = &i2c_timings[i2c_dev->mode];
+
+	st_i2c_soft_reset(i2c_dev);
+
+	val = SSC_CLR_REPSTRT | SSC_CLR_NACK | SSC_CLR_SSCARBL |
+		SSC_CLR_SSCAAS | SSC_CLR_SSCSTOP;
+	writel_relaxed(val, i2c_dev->base + SSC_CLR);
+
+	/* SSC Control register setup */
+	val = SSC_CTL_PO | SSC_CTL_PH | SSC_CTL_HB | SSC_CTL_DATA_WIDTH_9;
+	writel_relaxed(val, i2c_dev->base + SSC_CTL);
+
+	rate = clk_get_rate(i2c_dev->clk);
+	ns_per_clk = 1000000000 / rate;
+
+	/* Baudrate */
+	val = rate / (2 * t->rate);
+	writel_relaxed(val, i2c_dev->base + SSC_BRG);
+
+	/* Pre-scaler baudrate */
+	writel_relaxed(1, i2c_dev->base + SSC_PRE_SCALER_BRG);
+
+	/* Enable I2C mode */
+	writel_relaxed(SSC_I2C_I2CM, i2c_dev->base + SSC_I2C);
+
+	/* Repeated start hold time */
+	val = t->rep_start_hold / ns_per_clk;
+	writel_relaxed(val, i2c_dev->base + SSC_REP_START_HOLD);
+
+	/* Repeated start set up time */
+	val = t->rep_start_setup / ns_per_clk;
+	writel_relaxed(val, i2c_dev->base + SSC_REP_START_SETUP);
+
+	/* Start hold time */
+	val = t->start_hold / ns_per_clk;
+	writel_relaxed(val, i2c_dev->base + SSC_START_HOLD);
+
+	/* Data set up time */
+	val = t->data_setup_time / ns_per_clk;
+	writel_relaxed(val, i2c_dev->base + SSC_DATA_SETUP);
+
+	/* Stop set up time */
+	val = t->stop_setup_time / ns_per_clk;
+	writel_relaxed(val, i2c_dev->base + SSC_STOP_SETUP);
+
+	/* Bus free time */
+	val = t->bus_free_time / ns_per_clk;
+	writel_relaxed(val, i2c_dev->base + SSC_BUS_FREE);
+
+	/* Prescalers set up */
+	val = rate / 10000000;
+	writel_relaxed(val, i2c_dev->base + SSC_PRSCALER);
+	writel_relaxed(val, i2c_dev->base + SSC_PRSCALER_DATAOUT);
+
+	/* Noise suppression witdh */
+	val = i2c_dev->scl_min_width_us * rate / 100000000;
+	writel_relaxed(val, i2c_dev->base + SSC_NOISE_SUPP_WIDTH);
+
+	/* Noise suppression max output data delay width */
+	val = i2c_dev->sda_min_width_us * rate / 100000000;
+	writel_relaxed(val, i2c_dev->base + SSC_NOISE_SUPP_WIDTH_DATAOUT);
+}
+
+static int st_i2c_wait_free_bus(struct st_i2c_dev *i2c_dev)
+{
+	u32 sta;
+	int i;
+
+	for (i = 0; i < 10; i++) {
+		sta = readl_relaxed(i2c_dev->base + SSC_STA);
+		if (!(sta & SSC_STA_BUSY))
+			return 0;
+
+		usleep_range(2000, 4000);
+	}
+
+	dev_err(i2c_dev->dev, "bus not free (status = 0x%08x)\n", sta);
+
+	return -EBUSY;
+}
+
+/**
+ * st_i2c_write_tx_fifo() - Write a byte in the Tx FIFO
+ * @i2c_dev: Controller's private data
+ * @byte: Data to write in the Tx FIFO
+ */
+static inline void st_i2c_write_tx_fifo(struct st_i2c_dev *i2c_dev, u8 byte)
+{
+	u16 tbuf = byte << 1;
+
+	writel_relaxed(tbuf | 1, i2c_dev->base + SSC_TBUF);
+}
+
+/**
+ * st_i2c_wr_fill_tx_fifo() - Fill the Tx FIFO in write mode
+ * @i2c_dev: Controller's private data
+ *
+ * This functions fills the Tx FIFO with I2C transfert buffer when
+ * in write mode.
+ */
+static void st_i2c_wr_fill_tx_fifo(struct st_i2c_dev *i2c_dev)
+{
+	struct st_i2c_client *c = &i2c_dev->client;
+	u32 tx_fstat, sta;
+	int i;
+
+	sta = readl_relaxed(i2c_dev->base + SSC_STA);
+	if (sta & SSC_STA_TX_FIFO_FULL)
+		return;
+
+	tx_fstat = readl_relaxed(i2c_dev->base + SSC_TX_FSTAT);
+	tx_fstat &= SSC_TX_FSTAT_STATUS;
+
+	if (c->count < (SSC_TXFIFO_SIZE - tx_fstat))
+		i = c->count;
+	else
+		i = SSC_TXFIFO_SIZE - tx_fstat;
+
+	for (; i > 0; i--, c->count--, c->buf++)
+		st_i2c_write_tx_fifo(i2c_dev, *c->buf);
+}
+
+/**
+ * st_i2c_rd_fill_tx_fifo() - Fill the Tx FIFO in read mode
+ * @i2c_dev: Controller's private data
+ *
+ * This functions fills the Tx FIFO with fixed pattern when
+ * in read mode to trigger clock.
+ */
+static void st_i2c_rd_fill_tx_fifo(struct st_i2c_dev *i2c_dev, int max)
+{
+	struct st_i2c_client *c = &i2c_dev->client;
+	u32 tx_fstat, sta;
+	int i;
+
+	sta = readl_relaxed(i2c_dev->base + SSC_STA);
+	if (sta & SSC_STA_TX_FIFO_FULL)
+		return;
+
+	tx_fstat = readl_relaxed(i2c_dev->base + SSC_TX_FSTAT);
+	tx_fstat &= SSC_TX_FSTAT_STATUS;
+
+	if (max < (SSC_TXFIFO_SIZE - tx_fstat))
+		i = max;
+	else
+		i = SSC_TXFIFO_SIZE - tx_fstat;
+
+	for (; i > 0; i--, c->xfered++)
+		st_i2c_write_tx_fifo(i2c_dev, 0xff);
+}
+
+static void st_i2c_read_rx_fifo(struct st_i2c_dev *i2c_dev)
+{
+	struct st_i2c_client *c = &i2c_dev->client;
+	u32 i, sta;
+	u16 rbuf;
+
+	sta = readl_relaxed(i2c_dev->base + SSC_STA);
+	if (sta & SSC_STA_RIR) {
+		i = SSC_RXFIFO_SIZE;
+	} else {
+		i = readl_relaxed(i2c_dev->base + SSC_RX_FSTAT);
+		i &= SSC_RX_FSTAT_STATUS;
+	}
+
+	for (; (i > 0) && (c->count > 0); i--, c->count--) {
+		rbuf = readl_relaxed(i2c_dev->base + SSC_RBUF) >> 1;
+		*c->buf++ = (u8)rbuf & 0xff;
+	}
+
+	if (i) {
+		dev_err(i2c_dev->dev, "Unexpected %d bytes in rx fifo\n", i);
+		st_i2c_flush_rx_fifo(i2c_dev);
+	}
+}
+
+/**
+ * st_i2c_terminate_xfer() - Send either STOP or REPSTART condition
+ * @i2c_dev: Controller's private data
+ */
+static void st_i2c_terminate_xfer(struct st_i2c_dev *i2c_dev)
+{
+	struct st_i2c_client *c = &i2c_dev->client;
+
+	st_i2c_clr_bits(i2c_dev->base + SSC_IEN, SSC_IEN_TEEN);
+	st_i2c_clr_bits(i2c_dev->base + SSC_I2C, SSC_I2C_STRTG);
+
+	if (c->stop) {
+		st_i2c_set_bits(i2c_dev->base + SSC_IEN, SSC_IEN_STOPEN);
+		st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_STOPG);
+	} else {
+		st_i2c_set_bits(i2c_dev->base + SSC_IEN, SSC_IEN_REPSTRTEN);
+		st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_REPSTRTG);
+	}
+}
+
+/**
+ * st_i2c_handle_write() - Handle FIFO empty interrupt in case of write
+ * @i2c_dev: Controller's private data
+ */
+static void st_i2c_handle_write(struct st_i2c_dev *i2c_dev)
+{
+	struct st_i2c_client *c = &i2c_dev->client;
+
+	st_i2c_flush_rx_fifo(i2c_dev);
+
+	if (!c->count)
+		/* End of xfer, send stop or repstart */
+		st_i2c_terminate_xfer(i2c_dev);
+	else
+		st_i2c_wr_fill_tx_fifo(i2c_dev);
+}
+
+/**
+ * st_i2c_handle_write() - Handle FIFO enmpty interrupt in case of read
+ * @i2c_dev: Controller's private data
+ */
+static void st_i2c_handle_read(struct st_i2c_dev *i2c_dev)
+{
+	struct st_i2c_client *c = &i2c_dev->client;
+	u32 ien;
+
+	/* Trash the address read back */
+	if (!c->xfered) {
+		readl_relaxed(i2c_dev->base + SSC_RBUF);
+		st_i2c_clr_bits(i2c_dev->base + SSC_I2C, SSC_I2C_TXENB);
+	} else {
+		st_i2c_read_rx_fifo(i2c_dev);
+	}
+
+	if (!c->count) {
+		/* End of xfer, send stop or repstart */
+		st_i2c_terminate_xfer(i2c_dev);
+	} else if (c->count == 1) {
+		/* Penultimate byte to xfer, disable ACK gen. */
+		st_i2c_clr_bits(i2c_dev->base + SSC_I2C, SSC_I2C_ACKG);
+
+		/* Last received byte is to be handled by NACK interrupt */
+		ien = SSC_IEN_NACKEN | SSC_IEN_ARBLEN;
+		writel_relaxed(ien, i2c_dev->base + SSC_IEN);
+
+		st_i2c_rd_fill_tx_fifo(i2c_dev, c->count);
+	} else {
+		st_i2c_rd_fill_tx_fifo(i2c_dev, c->count - 1);
+	}
+}
+
+/**
+ * st_i2c_isr() - Interrupt routine
+ * @irq: interrupt number
+ * @data: Controller's private data
+ */
+static irqreturn_t st_i2c_isr_thread(int irq, void *data)
+{
+	struct st_i2c_dev *i2c_dev = data;
+	struct st_i2c_client *c = &i2c_dev->client;
+	u32 sta, ien;
+	int it;
+
+	ien = readl_relaxed(i2c_dev->base + SSC_IEN);
+	sta = readl_relaxed(i2c_dev->base + SSC_STA);
+
+	/* Use __fls() to check error bits first */
+	it = __fls(sta & ien);
+	if (it < 0) {
+		dev_dbg(i2c_dev->dev, "spurious it (sta=0x%04x, ien=0x%04x)\n",
+				sta, ien);
+		return IRQ_NONE;
+	}
+
+	switch (1 << it) {
+	case SSC_STA_TE:
+		if (c->addr & I2C_M_RD)
+			st_i2c_handle_read(i2c_dev);
+		else
+			st_i2c_handle_write(i2c_dev);
+		break;
+
+	case SSC_STA_STOP:
+	case SSC_STA_REPSTRT:
+		writel_relaxed(0, i2c_dev->base + SSC_IEN);
+		complete(&i2c_dev->complete);
+		break;
+
+	case SSC_STA_NACK:
+		writel_relaxed(SSC_CLR_NACK, i2c_dev->base + SSC_CLR);
+
+		/* Last received byte handled by NACK interrupt */
+		if ((c->addr & I2C_M_RD) && (c->count == 1) && (c->xfered)) {
+			st_i2c_handle_read(i2c_dev);
+			break;
+		}
+
+		it = SSC_IEN_STOPEN | SSC_IEN_ARBLEN;
+		writel_relaxed(it, i2c_dev->base + SSC_IEN);
+
+		st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_STOPG);
+		c->result = -EIO;
+		break;
+
+	case SSC_STA_ARBL:
+		writel_relaxed(SSC_CLR_SSCARBL, i2c_dev->base + SSC_CLR);
+
+		it = SSC_IEN_STOPEN | SSC_IEN_ARBLEN;
+		writel_relaxed(it, i2c_dev->base + SSC_IEN);
+
+		st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_STOPG);
+		c->result = -EIO;
+		break;
+
+	default:
+		dev_err(i2c_dev->dev,
+				"it %d unhandled (sta=0x%04x)\n", it, sta);
+	}
+
+	/*
+	 * Read IEN register to ensure interrupt mask write is effective
+	 * before re-enabling interrupt at GIC level, and thus avoid spurious
+	 * interrupts.
+	 */
+	readl(i2c_dev->base + SSC_IEN);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * st_i2c_xfer_msg() - Transfer a single I2C message
+ * @i2c_dev: Controller's private data
+ * @msg: I2C message to transfer
+ * @is_first: first message of the sequence
+ * @is_last: last message of the sequence
+ */
+static int st_i2c_xfer_msg(struct st_i2c_dev *i2c_dev, struct i2c_msg *msg,
+			    bool is_first, bool is_last)
+{
+	struct st_i2c_client *c = &i2c_dev->client;
+	u32 ctl, i2c, it;
+	unsigned long timeout;
+	int ret;
+
+	c->addr		= (u8)(msg->addr << 1);
+	c->addr		|= (msg->flags & I2C_M_RD);
+	c->buf		= msg->buf;
+	c->count	= msg->len;
+	c->xfered	= 0;
+	c->result	= 0;
+	c->stop		= is_last;
+
+	reinit_completion(&i2c_dev->complete);
+
+	ctl = SSC_CTL_EN | SSC_CTL_MS |	SSC_CTL_EN_RX_FIFO | SSC_CTL_EN_TX_FIFO;
+	st_i2c_set_bits(i2c_dev->base + SSC_CTL, ctl);
+
+	i2c = SSC_I2C_TXENB;
+	if (c->addr & I2C_M_RD)
+		i2c |= SSC_I2C_ACKG;
+	st_i2c_set_bits(i2c_dev->base + SSC_I2C, i2c);
+
+	/* Write slave address */
+	st_i2c_write_tx_fifo(i2c_dev, c->addr);
+
+	/* Pre-fill Tx fifo with data in case of write */
+	if (!(c->addr & I2C_M_RD))
+		st_i2c_wr_fill_tx_fifo(i2c_dev);
+
+	it = SSC_IEN_NACKEN | SSC_IEN_TEEN | SSC_IEN_ARBLEN;
+	writel_relaxed(it, i2c_dev->base + SSC_IEN);
+
+	if (is_first) {
+		ret = st_i2c_wait_free_bus(i2c_dev);
+		if (ret)
+			return ret;
+
+		st_i2c_set_bits(i2c_dev->base + SSC_I2C, SSC_I2C_STRTG);
+	}
+
+	timeout = wait_for_completion_timeout(&i2c_dev->complete,
+			i2c_dev->adap.timeout);
+	ret = c->result;
+
+	if (!timeout) {
+		dev_err(i2c_dev->dev, "Write to slave 0x%x timed out\n",
+				c->addr);
+		ret = -ETIMEDOUT;
+	}
+
+	i2c = SSC_I2C_STOPG | SSC_I2C_REPSTRTG;
+	st_i2c_clr_bits(i2c_dev->base + SSC_I2C, i2c);
+
+	writel_relaxed(SSC_CLR_SSCSTOP | SSC_CLR_REPSTRT,
+			i2c_dev->base + SSC_CLR);
+
+	return ret;
+}
+
+/**
+ * st_i2c_xfer() - Transfer a single I2C message
+ * @i2c_adap: Adapter pointer to the controller
+ * @msgs: Pointer to data to be written.
+ * @num: Number of messages to be executed
+ */
+static int st_i2c_xfer(struct i2c_adapter *i2c_adap,
+			struct i2c_msg msgs[], int num)
+{
+	struct st_i2c_dev *i2c_dev = i2c_get_adapdata(i2c_adap);
+	int ret, i;
+
+	i2c_dev->busy = true;
+
+	ret = clk_prepare_enable(i2c_dev->clk);
+	if (ret) {
+		dev_err(i2c_dev->dev, "Failed to prepare_enable clock\n");
+		return ret;
+	}
+
+	pinctrl_pm_select_default_state(i2c_dev->dev);
+
+	st_i2c_hw_config(i2c_dev);
+
+	for (i = 0; (i < num) && !ret; i++)
+		ret = st_i2c_xfer_msg(i2c_dev, &msgs[i], i == 0, i == num - 1);
+
+	pinctrl_pm_select_idle_state(i2c_dev->dev);
+
+	clk_disable_unprepare(i2c_dev->clk);
+
+	i2c_dev->busy = false;
+
+	return (ret < 0) ? ret : i;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int st_i2c_suspend(struct device *dev)
+{
+	struct platform_device *pdev =
+		container_of(dev, struct platform_device, dev);
+	struct st_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+
+	if (i2c_dev->busy)
+		return -EBUSY;
+
+	pinctrl_pm_select_sleep_state(dev);
+
+	return 0;
+}
+
+static int st_i2c_resume(struct device *dev)
+{
+	pinctrl_pm_select_default_state(dev);
+	/* Go in idle state if available */
+	pinctrl_pm_select_idle_state(dev);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(st_i2c_pm, st_i2c_suspend, st_i2c_resume);
+#define ST_I2C_PM	(&st_i2c_pm)
+#else
+#define ST_I2C_PM	NULL
+#endif
+
+static u32 st_i2c_func(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static struct i2c_algorithm st_i2c_algo = {
+	.master_xfer = st_i2c_xfer,
+	.functionality = st_i2c_func,
+};
+
+static int st_i2c_of_get_deglitch(struct device_node *np,
+		struct st_i2c_dev *i2c_dev)
+{
+	int ret;
+
+	ret = of_property_read_u32(np, "st,i2c-min-scl-pulse-width-us",
+			&i2c_dev->scl_min_width_us);
+	if ((ret == -ENODATA) || (ret == -EOVERFLOW)) {
+		dev_err(i2c_dev->dev, "st,i2c-min-scl-pulse-width-us invalid\n");
+		return ret;
+	}
+
+	ret = of_property_read_u32(np, "st,i2c-min-sda-pulse-width-us",
+			&i2c_dev->sda_min_width_us);
+	if ((ret == -ENODATA) || (ret == -EOVERFLOW)) {
+		dev_err(i2c_dev->dev, "st,i2c-min-sda-pulse-width-us invalid\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int st_i2c_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct st_i2c_dev *i2c_dev;
+	struct resource *res;
+	u32 clk_rate;
+	struct i2c_adapter *adap;
+	int ret;
+
+	i2c_dev = devm_kzalloc(&pdev->dev, sizeof(*i2c_dev), GFP_KERNEL);
+	if (!i2c_dev)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	i2c_dev->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(i2c_dev->base))
+		return PTR_ERR(i2c_dev->base);
+
+	i2c_dev->irq = irq_of_parse_and_map(np, 0);
+	if (!i2c_dev->irq) {
+		dev_err(&pdev->dev, "IRQ missing or invalid\n");
+		return -EINVAL;
+	}
+
+	i2c_dev->clk = of_clk_get_by_name(np, "ssc");
+	if (IS_ERR(i2c_dev->clk)) {
+		dev_err(&pdev->dev, "Unable to request clock\n");
+		return PTR_ERR(i2c_dev->clk);
+	}
+
+	i2c_dev->mode = I2C_MODE_STANDARD;
+	ret = of_property_read_u32(np, "clock-frequency", &clk_rate);
+	if ((!ret) && (clk_rate == 400000))
+		i2c_dev->mode = I2C_MODE_FAST;
+
+	i2c_dev->dev = &pdev->dev;
+
+	ret = devm_request_threaded_irq(&pdev->dev, i2c_dev->irq,
+			NULL, st_i2c_isr_thread,
+			IRQF_ONESHOT, pdev->name, i2c_dev);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to request irq %i\n", i2c_dev->irq);
+		return ret;
+	}
+
+	pinctrl_pm_select_default_state(i2c_dev->dev);
+	/* In case idle state available, select it */
+	pinctrl_pm_select_idle_state(i2c_dev->dev);
+
+	ret = st_i2c_of_get_deglitch(np, i2c_dev);
+	if (ret)
+		return ret;
+
+	adap = &i2c_dev->adap;
+	i2c_set_adapdata(adap, i2c_dev);
+	snprintf(adap->name, sizeof(adap->name), "ST I2C(0x%x)", res->start);
+	adap->owner = THIS_MODULE;
+	adap->timeout = 2 * HZ;
+	adap->retries = 0;
+	adap->algo = &st_i2c_algo;
+	adap->dev.parent = &pdev->dev;
+	adap->dev.of_node = pdev->dev.of_node;
+
+	init_completion(&i2c_dev->complete);
+
+	ret = i2c_add_adapter(adap);
+	if (ret) {
+		dev_err(&pdev->dev, "Failed to add adapter\n");
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, i2c_dev);
+
+	dev_info(i2c_dev->dev, "%s initialized\n", adap->name);
+
+	return 0;
+}
+
+static int st_i2c_remove(struct platform_device *pdev)
+{
+	struct st_i2c_dev *i2c_dev = platform_get_drvdata(pdev);
+
+	i2c_del_adapter(&i2c_dev->adap);
+
+	return 0;
+}
+
+static struct of_device_id st_i2c_match[] = {
+	{ .compatible = "st,comms-ssc-i2c", },
+	{ .compatible = "st,comms-ssc4-i2c", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, st_i2c_match);
+
+static struct platform_driver st_i2c_driver = {
+	.driver = {
+		.name = "st-i2c",
+		.owner = THIS_MODULE,
+		.of_match_table = st_i2c_match,
+		.pm = ST_I2C_PM,
+	},
+	.probe = st_i2c_probe,
+	.remove = st_i2c_remove,
+};
+
+module_platform_driver(st_i2c_driver);
+
+MODULE_AUTHOR("Maxime Coquelin <maxime.coquelin@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics I2C driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/i2c/busses/i2c-wmt.c b/drivers/i2c/busses/i2c-wmt.c
index 31395fa8121d..2c8a3e4f9008 100644
--- a/drivers/i2c/busses/i2c-wmt.c
+++ b/drivers/i2c/busses/i2c-wmt.c
@@ -349,6 +349,7 @@ static int wmt_i2c_reset_hardware(struct wmt_i2c_dev *i2c_dev)
 	err = clk_set_rate(i2c_dev->clk, 20000000);
 	if (err) {
 		dev_err(i2c_dev->dev, "failed to set clock = 20Mhz\n");
+		clk_disable_unprepare(i2c_dev->clk);
 		return err;
 	}
 
diff --git a/drivers/i2c/busses/i2c-xiic.c b/drivers/i2c/busses/i2c-xiic.c
index 4c8b368d463b..fc2716afdfd9 100644
--- a/drivers/i2c/busses/i2c-xiic.c
+++ b/drivers/i2c/busses/i2c-xiic.c
@@ -40,6 +40,7 @@
 #include <linux/i2c-xiic.h>
 #include <linux/io.h>
 #include <linux/slab.h>
+#include <linux/of.h>
 
 #define DRIVER_NAME "xiic-i2c"
 
@@ -702,7 +703,7 @@ static int xiic_i2c_probe(struct platform_device *pdev)
 	if (irq < 0)
 		goto resource_missing;
 
-	pdata = (struct xiic_i2c_platform_data *)dev_get_platdata(&pdev->dev);
+	pdata = dev_get_platdata(&pdev->dev);
 
 	i2c = kzalloc(sizeof(*i2c), GFP_KERNEL);
 	if (!i2c)
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 75ba8608383e..5923cfa390c8 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -248,7 +248,7 @@ static int i2c_device_probe(struct device *dev)
 	driver = to_i2c_driver(dev->driver);
 	if (!driver->probe || !driver->id_table)
 		return -ENODEV;
-	client->driver = driver;
+
 	if (!device_can_wakeup(&client->dev))
 		device_init_wakeup(&client->dev,
 					client->flags & I2C_CLIENT_WAKE);
@@ -257,7 +257,6 @@ static int i2c_device_probe(struct device *dev)
 	acpi_dev_pm_attach(&client->dev, true);
 	status = driver->probe(client, i2c_match_id(driver->id_table, client));
 	if (status) {
-		client->driver = NULL;
 		i2c_set_clientdata(client, NULL);
 		acpi_dev_pm_detach(&client->dev, true);
 	}
@@ -281,10 +280,8 @@ static int i2c_device_remove(struct device *dev)
 		dev->driver = NULL;
 		status = 0;
 	}
-	if (status == 0) {
-		client->driver = NULL;
+	if (status == 0)
 		i2c_set_clientdata(client, NULL);
-	}
 	acpi_dev_pm_detach(&client->dev, true);
 	return status;
 }
@@ -1614,9 +1611,14 @@ static int i2c_cmd(struct device *dev, void *_arg)
 {
 	struct i2c_client	*client = i2c_verify_client(dev);
 	struct i2c_cmd_arg	*arg = _arg;
+	struct i2c_driver	*driver;
+
+	if (!client || !client->dev.driver)
+		return 0;
 
-	if (client && client->driver && client->driver->command)
-		client->driver->command(client, arg->cmd, arg->arg);
+	driver = to_i2c_driver(client->dev.driver);
+	if (driver->command)
+		driver->command(client, arg->cmd, arg->arg);
 	return 0;
 }
 
diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index c3ccdea3d180..80b47e8ce030 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -102,8 +102,8 @@ static void return_i2c_dev(struct i2c_dev *i2c_dev)
 	kfree(i2c_dev);
 }
 
-static ssize_t show_adapter_name(struct device *dev,
-				 struct device_attribute *attr, char *buf)
+static ssize_t name_show(struct device *dev,
+			 struct device_attribute *attr, char *buf)
 {
 	struct i2c_dev *i2c_dev = i2c_dev_get_by_minor(MINOR(dev->devt));
 
@@ -111,7 +111,13 @@ static ssize_t show_adapter_name(struct device *dev,
 		return -ENODEV;
 	return sprintf(buf, "%s\n", i2c_dev->adap->name);
 }
-static DEVICE_ATTR(name, S_IRUGO, show_adapter_name, NULL);
+static DEVICE_ATTR_RO(name);
+
+static struct attribute *i2c_attrs[] = {
+	&dev_attr_name.attr,
+	NULL,
+};
+ATTRIBUTE_GROUPS(i2c);
 
 /* ------------------------------------------------------------------------- */
 
@@ -562,15 +568,10 @@ static int i2cdev_attach_adapter(struct device *dev, void *dummy)
 		res = PTR_ERR(i2c_dev->dev);
 		goto error;
 	}
-	res = device_create_file(i2c_dev->dev, &dev_attr_name);
-	if (res)
-		goto error_destroy;
 
 	pr_debug("i2c-dev: adapter [%s] registered as minor %d\n",
 		 adap->name, adap->nr);
 	return 0;
-error_destroy:
-	device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, adap->nr));
 error:
 	return_i2c_dev(i2c_dev);
 	return res;
@@ -589,7 +590,6 @@ static int i2cdev_detach_adapter(struct device *dev, void *dummy)
 	if (!i2c_dev) /* attach_adapter must have failed */
 		return 0;
 
-	device_remove_file(i2c_dev->dev, &dev_attr_name);
 	return_i2c_dev(i2c_dev);
 	device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, adap->nr));
 
@@ -637,6 +637,7 @@ static int __init i2c_dev_init(void)
 		res = PTR_ERR(i2c_dev_class);
 		goto out_unreg_chrdev;
 	}
+	i2c_dev_class->dev_groups = i2c_groups;
 
 	/* Keep track of adapters which will be added or removed later */
 	res = bus_register_notifier(&i2c_bus_type, &i2cdev_notifier);
diff --git a/drivers/i2c/i2c-smbus.c b/drivers/i2c/i2c-smbus.c
index 44d4c6071c15..c99b22987366 100644
--- a/drivers/i2c/i2c-smbus.c
+++ b/drivers/i2c/i2c-smbus.c
@@ -46,6 +46,7 @@ static int smbus_do_alert(struct device *dev, void *addrp)
 {
 	struct i2c_client *client = i2c_verify_client(dev);
 	struct alert_data *data = addrp;
+	struct i2c_driver *driver;
 
 	if (!client || client->addr != data->addr)
 		return 0;
@@ -54,12 +55,13 @@ static int smbus_do_alert(struct device *dev, void *addrp)
 
 	/*
 	 * Drivers should either disable alerts, or provide at least
-	 * a minimal handler.  Lock so client->driver won't change.
+	 * a minimal handler.  Lock so the driver won't change.
 	 */
 	device_lock(dev);
-	if (client->driver) {
-		if (client->driver->alert)
-			client->driver->alert(client, data->flag);
+	if (client->dev.driver) {
+		driver = to_i2c_driver(client->dev.driver);
+		if (driver->alert)
+			driver->alert(client, data->flag);
 		else
 			dev_warn(&client->dev, "no driver alert()!\n");
 	} else
diff --git a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
index 928656e241dd..c58e093b6032 100644
--- a/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
+++ b/drivers/i2c/muxes/i2c-arb-gpio-challenge.c
@@ -238,7 +238,7 @@ static struct platform_driver i2c_arbitrator_driver = {
 	.driver	= {
 		.owner	= THIS_MODULE,
 		.name	= "i2c-arb-gpio-challenge",
-		.of_match_table = of_match_ptr(i2c_arbitrator_of_match),
+		.of_match_table = i2c_arbitrator_of_match,
 	},
 };
 
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index a764da777f08..8a8c56f4b026 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -30,15 +30,15 @@ static void i2c_mux_gpio_set(const struct gpiomux *mux, unsigned val)
 	int i;
 
 	for (i = 0; i < mux->data.n_gpios; i++)
-		gpio_set_value(mux->gpio_base + mux->data.gpios[i],
-			       val & (1 << i));
+		gpio_set_value_cansleep(mux->gpio_base + mux->data.gpios[i],
+					val & (1 << i));
 }
 
 static int i2c_mux_gpio_select(struct i2c_adapter *adap, void *data, u32 chan)
 {
 	struct gpiomux *mux = data;
 
-	i2c_mux_gpio_set(mux, mux->data.values[chan]);
+	i2c_mux_gpio_set(mux, chan);
 
 	return 0;
 }
@@ -228,7 +228,7 @@ static int i2c_mux_gpio_probe(struct platform_device *pdev)
 		unsigned int class = mux->data.classes ? mux->data.classes[i] : 0;
 
 		mux->adap[i] = i2c_add_mux_adapter(parent, &pdev->dev, mux, nr,
-						   i, class,
+						   mux->data.values[i], class,
 						   i2c_mux_gpio_select, deselect);
 		if (!mux->adap[i]) {
 			ret = -ENODEV;
@@ -283,7 +283,7 @@ static struct platform_driver i2c_mux_gpio_driver = {
 	.driver	= {
 		.owner	= THIS_MODULE,
 		.name	= "i2c-mux-gpio",
-		.of_match_table = of_match_ptr(i2c_mux_gpio_of_match),
+		.of_match_table = i2c_mux_gpio_of_match,
 	},
 };
 
diff --git a/drivers/i2c/muxes/i2c-mux-pinctrl.c b/drivers/i2c/muxes/i2c-mux-pinctrl.c
index 68a37157377d..d7978dc4ad0b 100644
--- a/drivers/i2c/muxes/i2c-mux-pinctrl.c
+++ b/drivers/i2c/muxes/i2c-mux-pinctrl.c
@@ -24,6 +24,7 @@
 #include <linux/i2c-mux-pinctrl.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
+#include <linux/of.h>
 
 struct i2c_mux_pinctrl {
 	struct device *dev;
author	Linus Torvalds	2013-11-18 15:50:07 -0800
committer	Linus Torvalds	2013-11-18 15:50:07 -0800
commit	13509c3a9d20a9df93dc9b944e8bd20fe1b454a7 (patch)
tree	d7a97d1d10e88bcb93852cb0143a000710e9e246 /drivers/i2c
parent	1ea406c0e08c717241275064046d29b5bac1b1db (diff)
parent	cfff1f4a9367bfe0d88413e8807f8369e9564729 (diff)