Adding upstream version 6.1.76.upstream/6.1.76upstream

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

1 files changed, 1289 insertions, 0 deletions

diff --git a/drivers/i2c/busses/i2c-bcm-iproc.c b/drivers/i2c/busses/i2c-bcm-iproc.c
new file mode 100644
index 000000000..86a080f24
--- /dev/null
+++ b/drivers/i2c/busses/i2c-bcm-iproc.c
@@ -0,0 +1,1289 @@
+// SPDX-License-Identifier: GPL-2.0-only
+// Copyright (C) 2014 Broadcom Corporation
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#define IDM_CTRL_DIRECT_OFFSET       0x00
+#define CFG_OFFSET                   0x00
+#define CFG_RESET_SHIFT              31
+#define CFG_EN_SHIFT                 30
+#define CFG_SLAVE_ADDR_0_SHIFT       28
+#define CFG_M_RETRY_CNT_SHIFT        16
+#define CFG_M_RETRY_CNT_MASK         0x0f
+
+#define TIM_CFG_OFFSET               0x04
+#define TIM_CFG_MODE_400_SHIFT       31
+#define TIM_RAND_SLAVE_STRETCH_SHIFT      24
+#define TIM_RAND_SLAVE_STRETCH_MASK       0x7f
+#define TIM_PERIODIC_SLAVE_STRETCH_SHIFT  16
+#define TIM_PERIODIC_SLAVE_STRETCH_MASK   0x7f
+
+#define S_CFG_SMBUS_ADDR_OFFSET           0x08
+#define S_CFG_EN_NIC_SMB_ADDR3_SHIFT      31
+#define S_CFG_NIC_SMB_ADDR3_SHIFT         24
+#define S_CFG_NIC_SMB_ADDR3_MASK          0x7f
+#define S_CFG_EN_NIC_SMB_ADDR2_SHIFT      23
+#define S_CFG_NIC_SMB_ADDR2_SHIFT         16
+#define S_CFG_NIC_SMB_ADDR2_MASK          0x7f
+#define S_CFG_EN_NIC_SMB_ADDR1_SHIFT      15
+#define S_CFG_NIC_SMB_ADDR1_SHIFT         8
+#define S_CFG_NIC_SMB_ADDR1_MASK          0x7f
+#define S_CFG_EN_NIC_SMB_ADDR0_SHIFT      7
+#define S_CFG_NIC_SMB_ADDR0_SHIFT         0
+#define S_CFG_NIC_SMB_ADDR0_MASK          0x7f
+
+#define M_FIFO_CTRL_OFFSET           0x0c
+#define M_FIFO_RX_FLUSH_SHIFT        31
+#define M_FIFO_TX_FLUSH_SHIFT        30
+#define M_FIFO_RX_CNT_SHIFT          16
+#define M_FIFO_RX_CNT_MASK           0x7f
+#define M_FIFO_RX_THLD_SHIFT         8
+#define M_FIFO_RX_THLD_MASK          0x3f
+
+#define S_FIFO_CTRL_OFFSET           0x10
+#define S_FIFO_RX_FLUSH_SHIFT        31
+#define S_FIFO_TX_FLUSH_SHIFT        30
+#define S_FIFO_RX_CNT_SHIFT          16
+#define S_FIFO_RX_CNT_MASK           0x7f
+#define S_FIFO_RX_THLD_SHIFT         8
+#define S_FIFO_RX_THLD_MASK          0x3f
+
+#define M_CMD_OFFSET                 0x30
+#define M_CMD_START_BUSY_SHIFT       31
+#define M_CMD_STATUS_SHIFT           25
+#define M_CMD_STATUS_MASK            0x07
+#define M_CMD_STATUS_SUCCESS         0x0
+#define M_CMD_STATUS_LOST_ARB        0x1
+#define M_CMD_STATUS_NACK_ADDR       0x2
+#define M_CMD_STATUS_NACK_DATA       0x3
+#define M_CMD_STATUS_TIMEOUT         0x4
+#define M_CMD_STATUS_FIFO_UNDERRUN   0x5
+#define M_CMD_STATUS_RX_FIFO_FULL    0x6
+#define M_CMD_PROTOCOL_SHIFT         9
+#define M_CMD_PROTOCOL_MASK          0xf
+#define M_CMD_PROTOCOL_QUICK         0x0
+#define M_CMD_PROTOCOL_BLK_WR        0x7
+#define M_CMD_PROTOCOL_BLK_RD        0x8
+#define M_CMD_PROTOCOL_PROCESS       0xa
+#define M_CMD_PEC_SHIFT              8
+#define M_CMD_RD_CNT_SHIFT           0
+#define M_CMD_RD_CNT_MASK            0xff
+
+#define S_CMD_OFFSET                 0x34
+#define S_CMD_START_BUSY_SHIFT       31
+#define S_CMD_STATUS_SHIFT           23
+#define S_CMD_STATUS_MASK            0x07
+#define S_CMD_STATUS_SUCCESS         0x0
+#define S_CMD_STATUS_TIMEOUT         0x5
+#define S_CMD_STATUS_MASTER_ABORT    0x7
+
+#define IE_OFFSET                    0x38
+#define IE_M_RX_FIFO_FULL_SHIFT      31
+#define IE_M_RX_THLD_SHIFT           30
+#define IE_M_START_BUSY_SHIFT        28
+#define IE_M_TX_UNDERRUN_SHIFT       27
+#define IE_S_RX_FIFO_FULL_SHIFT      26
+#define IE_S_RX_THLD_SHIFT           25
+#define IE_S_RX_EVENT_SHIFT          24
+#define IE_S_START_BUSY_SHIFT        23
+#define IE_S_TX_UNDERRUN_SHIFT       22
+#define IE_S_RD_EVENT_SHIFT          21
+
+#define IS_OFFSET                    0x3c
+#define IS_M_RX_FIFO_FULL_SHIFT      31
+#define IS_M_RX_THLD_SHIFT           30
+#define IS_M_START_BUSY_SHIFT        28
+#define IS_M_TX_UNDERRUN_SHIFT       27
+#define IS_S_RX_FIFO_FULL_SHIFT      26
+#define IS_S_RX_THLD_SHIFT           25
+#define IS_S_RX_EVENT_SHIFT          24
+#define IS_S_START_BUSY_SHIFT        23
+#define IS_S_TX_UNDERRUN_SHIFT       22
+#define IS_S_RD_EVENT_SHIFT          21
+
+#define M_TX_OFFSET                  0x40
+#define M_TX_WR_STATUS_SHIFT         31
+#define M_TX_DATA_SHIFT              0
+#define M_TX_DATA_MASK               0xff
+
+#define M_RX_OFFSET                  0x44
+#define M_RX_STATUS_SHIFT            30
+#define M_RX_STATUS_MASK             0x03
+#define M_RX_PEC_ERR_SHIFT           29
+#define M_RX_DATA_SHIFT              0
+#define M_RX_DATA_MASK               0xff
+
+#define S_TX_OFFSET                  0x48
+#define S_TX_WR_STATUS_SHIFT         31
+#define S_TX_DATA_SHIFT              0
+#define S_TX_DATA_MASK               0xff
+
+#define S_RX_OFFSET                  0x4c
+#define S_RX_STATUS_SHIFT            30
+#define S_RX_STATUS_MASK             0x03
+#define S_RX_PEC_ERR_SHIFT           29
+#define S_RX_DATA_SHIFT              0
+#define S_RX_DATA_MASK               0xff
+
+#define I2C_TIMEOUT_MSEC             50000
+#define M_TX_RX_FIFO_SIZE            64
+#define M_RX_FIFO_MAX_THLD_VALUE     (M_TX_RX_FIFO_SIZE - 1)
+
+#define M_RX_MAX_READ_LEN            255
+#define M_RX_FIFO_THLD_VALUE         50
+
+#define IE_M_ALL_INTERRUPT_SHIFT     27
+#define IE_M_ALL_INTERRUPT_MASK      0x1e
+
+#define SLAVE_READ_WRITE_BIT_MASK    0x1
+#define SLAVE_READ_WRITE_BIT_SHIFT   0x1
+#define SLAVE_MAX_SIZE_TRANSACTION   64
+#define SLAVE_CLOCK_STRETCH_TIME     25
+
+#define IE_S_ALL_INTERRUPT_SHIFT     21
+#define IE_S_ALL_INTERRUPT_MASK      0x3f
+/*
+ * It takes ~18us to reading 10bytes of data, hence to keep tasklet
+ * running for less time, max slave read per tasklet is set to 10 bytes.
+ */
+#define MAX_SLAVE_RX_PER_INT         10
+
+enum i2c_slave_read_status {
+	I2C_SLAVE_RX_FIFO_EMPTY = 0,
+	I2C_SLAVE_RX_START,
+	I2C_SLAVE_RX_DATA,
+	I2C_SLAVE_RX_END,
+};
+
+enum bus_speed_index {
+	I2C_SPD_100K = 0,
+	I2C_SPD_400K,
+};
+
+enum bcm_iproc_i2c_type {
+	IPROC_I2C,
+	IPROC_I2C_NIC
+};
+
+struct bcm_iproc_i2c_dev {
+	struct device *device;
+	enum bcm_iproc_i2c_type type;
+	int irq;
+
+	void __iomem *base;
+	void __iomem *idm_base;
+
+	u32 ape_addr_mask;
+
+	/* lock for indirect access through IDM */
+	spinlock_t idm_lock;
+
+	struct i2c_adapter adapter;
+	unsigned int bus_speed;
+
+	struct completion done;
+	int xfer_is_done;
+
+	struct i2c_msg *msg;
+
+	struct i2c_client *slave;
+
+	/* bytes that have been transferred */
+	unsigned int tx_bytes;
+	/* bytes that have been read */
+	unsigned int rx_bytes;
+	unsigned int thld_bytes;
+
+	bool slave_rx_only;
+	bool rx_start_rcvd;
+	bool slave_read_complete;
+	u32 tx_underrun;
+	u32 slave_int_mask;
+	struct tasklet_struct slave_rx_tasklet;
+};
+
+/* tasklet to process slave rx data */
+static void slave_rx_tasklet_fn(unsigned long);
+
+/*
+ * Can be expanded in the future if more interrupt status bits are utilized
+ */
+#define ISR_MASK (BIT(IS_M_START_BUSY_SHIFT) | BIT(IS_M_TX_UNDERRUN_SHIFT)\
+		| BIT(IS_M_RX_THLD_SHIFT))
+
+#define ISR_MASK_SLAVE (BIT(IS_S_START_BUSY_SHIFT)\
+		| BIT(IS_S_RX_EVENT_SHIFT) | BIT(IS_S_RD_EVENT_SHIFT)\
+		| BIT(IS_S_TX_UNDERRUN_SHIFT) | BIT(IS_S_RX_FIFO_FULL_SHIFT)\
+		| BIT(IS_S_RX_THLD_SHIFT))
+
+static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave);
+static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave);
+static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c,
+					 bool enable);
+
+static inline u32 iproc_i2c_rd_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
+				   u32 offset)
+{
+	u32 val;
+	unsigned long flags;
+
+	if (iproc_i2c->idm_base) {
+		spin_lock_irqsave(&iproc_i2c->idm_lock, flags);
+		writel(iproc_i2c->ape_addr_mask,
+		       iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
+		val = readl(iproc_i2c->base + offset);
+		spin_unlock_irqrestore(&iproc_i2c->idm_lock, flags);
+	} else {
+		val = readl(iproc_i2c->base + offset);
+	}
+
+	return val;
+}
+
+static inline void iproc_i2c_wr_reg(struct bcm_iproc_i2c_dev *iproc_i2c,
+				    u32 offset, u32 val)
+{
+	unsigned long flags;
+
+	if (iproc_i2c->idm_base) {
+		spin_lock_irqsave(&iproc_i2c->idm_lock, flags);
+		writel(iproc_i2c->ape_addr_mask,
+		       iproc_i2c->idm_base + IDM_CTRL_DIRECT_OFFSET);
+		writel(val, iproc_i2c->base + offset);
+		spin_unlock_irqrestore(&iproc_i2c->idm_lock, flags);
+	} else {
+		writel(val, iproc_i2c->base + offset);
+	}
+}
+
+static void bcm_iproc_i2c_slave_init(
+	struct bcm_iproc_i2c_dev *iproc_i2c, bool need_reset)
+{
+	u32 val;
+
+	iproc_i2c->tx_underrun = 0;
+	if (need_reset) {
+		/* put controller in reset */
+		val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
+		val |= BIT(CFG_RESET_SHIFT);
+		iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
+
+		/* wait 100 usec per spec */
+		udelay(100);
+
+		/* bring controller out of reset */
+		val &= ~(BIT(CFG_RESET_SHIFT));
+		iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
+	}
+
+	/* flush TX/RX FIFOs */
+	val = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT));
+	iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, val);
+
+	/* Maximum slave stretch time */
+	val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
+	val &= ~(TIM_RAND_SLAVE_STRETCH_MASK << TIM_RAND_SLAVE_STRETCH_SHIFT);
+	val |= (SLAVE_CLOCK_STRETCH_TIME << TIM_RAND_SLAVE_STRETCH_SHIFT);
+	iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
+
+	/* Configure the slave address */
+	val = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET);
+	val |= BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT);
+	val &= ~(S_CFG_NIC_SMB_ADDR3_MASK << S_CFG_NIC_SMB_ADDR3_SHIFT);
+	val |= (iproc_i2c->slave->addr << S_CFG_NIC_SMB_ADDR3_SHIFT);
+	iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, val);
+
+	/* clear all pending slave interrupts */
+	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE);
+
+	/* Enable interrupt register to indicate a valid byte in receive fifo */
+	val = BIT(IE_S_RX_EVENT_SHIFT);
+	/* Enable interrupt register to indicate Slave Rx FIFO Full */
+	val |= BIT(IE_S_RX_FIFO_FULL_SHIFT);
+	/* Enable interrupt register to indicate a Master read transaction */
+	val |= BIT(IE_S_RD_EVENT_SHIFT);
+	/* Enable interrupt register for the Slave BUSY command */
+	val |= BIT(IE_S_START_BUSY_SHIFT);
+	iproc_i2c->slave_int_mask = val;
+	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
+}
+
+static bool bcm_iproc_i2c_check_slave_status
+	(struct bcm_iproc_i2c_dev *iproc_i2c, u32 status)
+{
+	u32 val;
+	bool recover = false;
+
+	/* check slave transmit status only if slave is transmitting */
+	if (!iproc_i2c->slave_rx_only) {
+		val = iproc_i2c_rd_reg(iproc_i2c, S_CMD_OFFSET);
+		/* status is valid only when START_BUSY is cleared */
+		if (!(val & BIT(S_CMD_START_BUSY_SHIFT))) {
+			val = (val >> S_CMD_STATUS_SHIFT) & S_CMD_STATUS_MASK;
+			if (val == S_CMD_STATUS_TIMEOUT ||
+			    val == S_CMD_STATUS_MASTER_ABORT) {
+				dev_warn(iproc_i2c->device,
+					 (val == S_CMD_STATUS_TIMEOUT) ?
+					 "slave random stretch time timeout\n" :
+					 "Master aborted read transaction\n");
+				recover = true;
+			}
+		}
+	}
+
+	/* RX_EVENT is not valid when START_BUSY is set */
+	if ((status & BIT(IS_S_RX_EVENT_SHIFT)) &&
+	    (status & BIT(IS_S_START_BUSY_SHIFT))) {
+		dev_warn(iproc_i2c->device, "Slave aborted read transaction\n");
+		recover = true;
+	}
+
+	if (recover) {
+		/* re-initialize i2c for recovery */
+		bcm_iproc_i2c_enable_disable(iproc_i2c, false);
+		bcm_iproc_i2c_slave_init(iproc_i2c, true);
+		bcm_iproc_i2c_enable_disable(iproc_i2c, true);
+	}
+
+	return recover;
+}
+
+static void bcm_iproc_i2c_slave_read(struct bcm_iproc_i2c_dev *iproc_i2c)
+{
+	u8 rx_data, rx_status;
+	u32 rx_bytes = 0;
+	u32 val;
+
+	while (rx_bytes < MAX_SLAVE_RX_PER_INT) {
+		val = iproc_i2c_rd_reg(iproc_i2c, S_RX_OFFSET);
+		rx_status = (val >> S_RX_STATUS_SHIFT) & S_RX_STATUS_MASK;
+		rx_data = ((val >> S_RX_DATA_SHIFT) & S_RX_DATA_MASK);
+
+		if (rx_status == I2C_SLAVE_RX_START) {
+			/* Start of SMBUS Master write */
+			i2c_slave_event(iproc_i2c->slave,
+					I2C_SLAVE_WRITE_REQUESTED, &rx_data);
+			iproc_i2c->rx_start_rcvd = true;
+			iproc_i2c->slave_read_complete = false;
+		} else if (rx_status == I2C_SLAVE_RX_DATA &&
+			   iproc_i2c->rx_start_rcvd) {
+			/* Middle of SMBUS Master write */
+			i2c_slave_event(iproc_i2c->slave,
+					I2C_SLAVE_WRITE_RECEIVED, &rx_data);
+		} else if (rx_status == I2C_SLAVE_RX_END &&
+			   iproc_i2c->rx_start_rcvd) {
+			/* End of SMBUS Master write */
+			if (iproc_i2c->slave_rx_only)
+				i2c_slave_event(iproc_i2c->slave,
+						I2C_SLAVE_WRITE_RECEIVED,
+						&rx_data);
+
+			i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP,
+					&rx_data);
+		} else if (rx_status == I2C_SLAVE_RX_FIFO_EMPTY) {
+			iproc_i2c->rx_start_rcvd = false;
+			iproc_i2c->slave_read_complete = true;
+			break;
+		}
+
+		rx_bytes++;
+	}
+}
+
+static void slave_rx_tasklet_fn(unsigned long data)
+{
+	struct bcm_iproc_i2c_dev *iproc_i2c = (struct bcm_iproc_i2c_dev *)data;
+	u32 int_clr;
+
+	bcm_iproc_i2c_slave_read(iproc_i2c);
+
+	/* clear pending IS_S_RX_EVENT_SHIFT interrupt */
+	int_clr = BIT(IS_S_RX_EVENT_SHIFT);
+
+	if (!iproc_i2c->slave_rx_only && iproc_i2c->slave_read_complete) {
+		/*
+		 * In case of single byte master-read request,
+		 * IS_S_TX_UNDERRUN_SHIFT event is generated before
+		 * IS_S_START_BUSY_SHIFT event. Hence start slave data send
+		 * from first IS_S_TX_UNDERRUN_SHIFT event.
+		 *
+		 * This means don't send any data from slave when
+		 * IS_S_RD_EVENT_SHIFT event is generated else it will increment
+		 * eeprom or other backend slave driver read pointer twice.
+		 */
+		iproc_i2c->tx_underrun = 0;
+		iproc_i2c->slave_int_mask |= BIT(IE_S_TX_UNDERRUN_SHIFT);
+
+		/* clear IS_S_RD_EVENT_SHIFT interrupt */
+		int_clr |= BIT(IS_S_RD_EVENT_SHIFT);
+	}
+
+	/* clear slave interrupt */
+	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, int_clr);
+	/* enable slave interrupts */
+	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, iproc_i2c->slave_int_mask);
+}
+
+static bool bcm_iproc_i2c_slave_isr(struct bcm_iproc_i2c_dev *iproc_i2c,
+				    u32 status)
+{
+	u32 val;
+	u8 value;
+
+
+	if (status & BIT(IS_S_TX_UNDERRUN_SHIFT)) {
+		iproc_i2c->tx_underrun++;
+		if (iproc_i2c->tx_underrun == 1)
+			/* Start of SMBUS for Master Read */
+			i2c_slave_event(iproc_i2c->slave,
+					I2C_SLAVE_READ_REQUESTED,
+					&value);
+		else
+			/* Master read other than start */
+			i2c_slave_event(iproc_i2c->slave,
+					I2C_SLAVE_READ_PROCESSED,
+					&value);
+
+		iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, value);
+		/* start transfer */
+		val = BIT(S_CMD_START_BUSY_SHIFT);
+		iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val);
+
+		/* clear interrupt */
+		iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET,
+				 BIT(IS_S_TX_UNDERRUN_SHIFT));
+	}
+
+	/* Stop received from master in case of master read transaction */
+	if (status & BIT(IS_S_START_BUSY_SHIFT)) {
+		/*
+		 * Disable interrupt for TX FIFO becomes empty and
+		 * less than PKT_LENGTH bytes were output on the SMBUS
+		 */
+		iproc_i2c->slave_int_mask &= ~BIT(IE_S_TX_UNDERRUN_SHIFT);
+		val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
+		val &= ~BIT(IE_S_TX_UNDERRUN_SHIFT);
+		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
+
+		/* End of SMBUS for Master Read */
+		val = BIT(S_TX_WR_STATUS_SHIFT);
+		iproc_i2c_wr_reg(iproc_i2c, S_TX_OFFSET, val);
+
+		val = BIT(S_CMD_START_BUSY_SHIFT);
+		iproc_i2c_wr_reg(iproc_i2c, S_CMD_OFFSET, val);
+
+		/* flush TX FIFOs */
+		val = iproc_i2c_rd_reg(iproc_i2c, S_FIFO_CTRL_OFFSET);
+		val |= (BIT(S_FIFO_TX_FLUSH_SHIFT));
+		iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, val);
+
+		i2c_slave_event(iproc_i2c->slave, I2C_SLAVE_STOP, &value);
+
+		/* clear interrupt */
+		iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET,
+				 BIT(IS_S_START_BUSY_SHIFT));
+	}
+
+	/* if the controller has been reset, immediately return from the ISR */
+	if (bcm_iproc_i2c_check_slave_status(iproc_i2c, status))
+		return true;
+
+	/*
+	 * Slave events in case of master-write, master-write-read and,
+	 * master-read
+	 *
+	 * Master-write     : only IS_S_RX_EVENT_SHIFT event
+	 * Master-write-read: both IS_S_RX_EVENT_SHIFT and IS_S_RD_EVENT_SHIFT
+	 *                    events
+	 * Master-read      : both IS_S_RX_EVENT_SHIFT and IS_S_RD_EVENT_SHIFT
+	 *                    events or only IS_S_RD_EVENT_SHIFT
+	 *
+	 * iproc has a slave rx fifo size of 64 bytes. Rx fifo full interrupt
+	 * (IS_S_RX_FIFO_FULL_SHIFT) will be generated when RX fifo becomes
+	 * full. This can happen if Master issues write requests of more than
+	 * 64 bytes.
+	 */
+	if (status & BIT(IS_S_RX_EVENT_SHIFT) ||
+	    status & BIT(IS_S_RD_EVENT_SHIFT) ||
+	    status & BIT(IS_S_RX_FIFO_FULL_SHIFT)) {
+		/* disable slave interrupts */
+		val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
+		val &= ~iproc_i2c->slave_int_mask;
+		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
+
+		if (status & BIT(IS_S_RD_EVENT_SHIFT))
+			/* Master-write-read request */
+			iproc_i2c->slave_rx_only = false;
+		else
+			/* Master-write request only */
+			iproc_i2c->slave_rx_only = true;
+
+		/* schedule tasklet to read data later */
+		tasklet_schedule(&iproc_i2c->slave_rx_tasklet);
+
+		/* clear IS_S_RX_FIFO_FULL_SHIFT interrupt */
+		if (status & BIT(IS_S_RX_FIFO_FULL_SHIFT)) {
+			val = BIT(IS_S_RX_FIFO_FULL_SHIFT);
+			iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, val);
+		}
+	}
+
+	return true;
+}
+
+static void bcm_iproc_i2c_read_valid_bytes(struct bcm_iproc_i2c_dev *iproc_i2c)
+{
+	struct i2c_msg *msg = iproc_i2c->msg;
+	uint32_t val;
+
+	/* Read valid data from RX FIFO */
+	while (iproc_i2c->rx_bytes < msg->len) {
+		val = iproc_i2c_rd_reg(iproc_i2c, M_RX_OFFSET);
+
+		/* rx fifo empty */
+		if (!((val >> M_RX_STATUS_SHIFT) & M_RX_STATUS_MASK))
+			break;
+
+		msg->buf[iproc_i2c->rx_bytes] =
+			(val >> M_RX_DATA_SHIFT) & M_RX_DATA_MASK;
+		iproc_i2c->rx_bytes++;
+	}
+}
+
+static void bcm_iproc_i2c_send(struct bcm_iproc_i2c_dev *iproc_i2c)
+{
+	struct i2c_msg *msg = iproc_i2c->msg;
+	unsigned int tx_bytes = msg->len - iproc_i2c->tx_bytes;
+	unsigned int i;
+	u32 val;
+
+	/* can only fill up to the FIFO size */
+	tx_bytes = min_t(unsigned int, tx_bytes, M_TX_RX_FIFO_SIZE);
+	for (i = 0; i < tx_bytes; i++) {
+		/* start from where we left over */
+		unsigned int idx = iproc_i2c->tx_bytes + i;
+
+		val = msg->buf[idx];
+
+		/* mark the last byte */
+		if (idx == msg->len - 1) {
+			val |= BIT(M_TX_WR_STATUS_SHIFT);
+
+			if (iproc_i2c->irq) {
+				u32 tmp;
+
+				/*
+				 * Since this is the last byte, we should now
+				 * disable TX FIFO underrun interrupt
+				 */
+				tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
+				tmp &= ~BIT(IE_M_TX_UNDERRUN_SHIFT);
+				iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET,
+						 tmp);
+			}
+		}
+
+		/* load data into TX FIFO */
+		iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);
+	}
+
+	/* update number of transferred bytes */
+	iproc_i2c->tx_bytes += tx_bytes;
+}
+
+static void bcm_iproc_i2c_read(struct bcm_iproc_i2c_dev *iproc_i2c)
+{
+	struct i2c_msg *msg = iproc_i2c->msg;
+	u32 bytes_left, val;
+
+	bcm_iproc_i2c_read_valid_bytes(iproc_i2c);
+	bytes_left = msg->len - iproc_i2c->rx_bytes;
+	if (bytes_left == 0) {
+		if (iproc_i2c->irq) {
+			/* finished reading all data, disable rx thld event */
+			val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
+			val &= ~BIT(IS_M_RX_THLD_SHIFT);
+			iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
+		}
+	} else if (bytes_left < iproc_i2c->thld_bytes) {
+		/* set bytes left as threshold */
+		val = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET);
+		val &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT);
+		val |= (bytes_left << M_FIFO_RX_THLD_SHIFT);
+		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
+		iproc_i2c->thld_bytes = bytes_left;
+	}
+	/*
+	 * bytes_left >= iproc_i2c->thld_bytes,
+	 * hence no need to change the THRESHOLD SET.
+	 * It will remain as iproc_i2c->thld_bytes itself
+	 */
+}
+
+static void bcm_iproc_i2c_process_m_event(struct bcm_iproc_i2c_dev *iproc_i2c,
+					  u32 status)
+{
+	/* TX FIFO is empty and we have more data to send */
+	if (status & BIT(IS_M_TX_UNDERRUN_SHIFT))
+		bcm_iproc_i2c_send(iproc_i2c);
+
+	/* RX FIFO threshold is reached and data needs to be read out */
+	if (status & BIT(IS_M_RX_THLD_SHIFT))
+		bcm_iproc_i2c_read(iproc_i2c);
+
+	/* transfer is done */
+	if (status & BIT(IS_M_START_BUSY_SHIFT)) {
+		iproc_i2c->xfer_is_done = 1;
+		if (iproc_i2c->irq)
+			complete(&iproc_i2c->done);
+	}
+}
+
+static irqreturn_t bcm_iproc_i2c_isr(int irq, void *data)
+{
+	struct bcm_iproc_i2c_dev *iproc_i2c = data;
+	u32 slave_status;
+	u32 status;
+	bool ret;
+
+	status = iproc_i2c_rd_reg(iproc_i2c, IS_OFFSET);
+	/* process only slave interrupt which are enabled */
+	slave_status = status & iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET) &
+		       ISR_MASK_SLAVE;
+
+	if (slave_status) {
+		ret = bcm_iproc_i2c_slave_isr(iproc_i2c, slave_status);
+		if (ret)
+			return IRQ_HANDLED;
+		else
+			return IRQ_NONE;
+	}
+
+	status &= ISR_MASK;
+	if (!status)
+		return IRQ_NONE;
+
+	/* process all master based events */
+	bcm_iproc_i2c_process_m_event(iproc_i2c, status);
+	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status);
+
+	return IRQ_HANDLED;
+}
+
+static int bcm_iproc_i2c_init(struct bcm_iproc_i2c_dev *iproc_i2c)
+{
+	u32 val;
+
+	/* put controller in reset */
+	val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
+	val |= BIT(CFG_RESET_SHIFT);
+	val &= ~(BIT(CFG_EN_SHIFT));
+	iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
+
+	/* wait 100 usec per spec */
+	udelay(100);
+
+	/* bring controller out of reset */
+	val &= ~(BIT(CFG_RESET_SHIFT));
+	iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
+
+	/* flush TX/RX FIFOs and set RX FIFO threshold to zero */
+	val = (BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT));
+	iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
+	/* disable all interrupts */
+	val = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
+	val &= ~(IE_M_ALL_INTERRUPT_MASK <<
+			IE_M_ALL_INTERRUPT_SHIFT);
+	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val);
+
+	/* clear all pending interrupts */
+	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, 0xffffffff);
+
+	return 0;
+}
+
+static void bcm_iproc_i2c_enable_disable(struct bcm_iproc_i2c_dev *iproc_i2c,
+					 bool enable)
+{
+	u32 val;
+
+	val = iproc_i2c_rd_reg(iproc_i2c, CFG_OFFSET);
+	if (enable)
+		val |= BIT(CFG_EN_SHIFT);
+	else
+		val &= ~BIT(CFG_EN_SHIFT);
+	iproc_i2c_wr_reg(iproc_i2c, CFG_OFFSET, val);
+}
+
+static int bcm_iproc_i2c_check_status(struct bcm_iproc_i2c_dev *iproc_i2c,
+				      struct i2c_msg *msg)
+{
+	u32 val;
+
+	val = iproc_i2c_rd_reg(iproc_i2c, M_CMD_OFFSET);
+	val = (val >> M_CMD_STATUS_SHIFT) & M_CMD_STATUS_MASK;
+
+	switch (val) {
+	case M_CMD_STATUS_SUCCESS:
+		return 0;
+
+	case M_CMD_STATUS_LOST_ARB:
+		dev_dbg(iproc_i2c->device, "lost bus arbitration\n");
+		return -EAGAIN;
+
+	case M_CMD_STATUS_NACK_ADDR:
+		dev_dbg(iproc_i2c->device, "NAK addr:0x%02x\n", msg->addr);
+		return -ENXIO;
+
+	case M_CMD_STATUS_NACK_DATA:
+		dev_dbg(iproc_i2c->device, "NAK data\n");
+		return -ENXIO;
+
+	case M_CMD_STATUS_TIMEOUT:
+		dev_dbg(iproc_i2c->device, "bus timeout\n");
+		return -ETIMEDOUT;
+
+	case M_CMD_STATUS_FIFO_UNDERRUN:
+		dev_dbg(iproc_i2c->device, "FIFO under-run\n");
+		return -ENXIO;
+
+	case M_CMD_STATUS_RX_FIFO_FULL:
+		dev_dbg(iproc_i2c->device, "RX FIFO full\n");
+		return -ETIMEDOUT;
+
+	default:
+		dev_dbg(iproc_i2c->device, "unknown error code=%d\n", val);
+
+		/* re-initialize i2c for recovery */
+		bcm_iproc_i2c_enable_disable(iproc_i2c, false);
+		bcm_iproc_i2c_init(iproc_i2c);
+		bcm_iproc_i2c_enable_disable(iproc_i2c, true);
+
+		return -EIO;
+	}
+}
+
+static int bcm_iproc_i2c_xfer_wait(struct bcm_iproc_i2c_dev *iproc_i2c,
+				   struct i2c_msg *msg,
+				   u32 cmd)
+{
+	unsigned long time_left = msecs_to_jiffies(I2C_TIMEOUT_MSEC);
+	u32 val, status;
+	int ret;
+
+	iproc_i2c_wr_reg(iproc_i2c, M_CMD_OFFSET, cmd);
+
+	if (iproc_i2c->irq) {
+		time_left = wait_for_completion_timeout(&iproc_i2c->done,
+							time_left);
+		/* disable all interrupts */
+		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
+		/* read it back to flush the write */
+		iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
+		/* make sure the interrupt handler isn't running */
+		synchronize_irq(iproc_i2c->irq);
+
+	} else { /* polling mode */
+		unsigned long timeout = jiffies + time_left;
+
+		do {
+			status = iproc_i2c_rd_reg(iproc_i2c,
+						  IS_OFFSET) & ISR_MASK;
+			bcm_iproc_i2c_process_m_event(iproc_i2c, status);
+			iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, status);
+
+			if (time_after(jiffies, timeout)) {
+				time_left = 0;
+				break;
+			}
+
+			cpu_relax();
+			cond_resched();
+		} while (!iproc_i2c->xfer_is_done);
+	}
+
+	if (!time_left && !iproc_i2c->xfer_is_done) {
+		dev_err(iproc_i2c->device, "transaction timed out\n");
+
+		/* flush both TX/RX FIFOs */
+		val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
+		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
+		return -ETIMEDOUT;
+	}
+
+	ret = bcm_iproc_i2c_check_status(iproc_i2c, msg);
+	if (ret) {
+		/* flush both TX/RX FIFOs */
+		val = BIT(M_FIFO_RX_FLUSH_SHIFT) | BIT(M_FIFO_TX_FLUSH_SHIFT);
+		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, val);
+		return ret;
+	}
+
+	return 0;
+}
+
+/*
+ * If 'process_call' is true, then this is a multi-msg transfer that requires
+ * a repeated start between the messages.
+ * More specifically, it must be a write (reg) followed by a read (data).
+ * The i2c quirks are set to enforce this rule.
+ */
+static int bcm_iproc_i2c_xfer_internal(struct bcm_iproc_i2c_dev *iproc_i2c,
+					struct i2c_msg *msgs, bool process_call)
+{
+	int i;
+	u8 addr;
+	u32 val, tmp, val_intr_en;
+	unsigned int tx_bytes;
+	struct i2c_msg *msg = &msgs[0];
+
+	/* check if bus is busy */
+	if (!!(iproc_i2c_rd_reg(iproc_i2c,
+				M_CMD_OFFSET) & BIT(M_CMD_START_BUSY_SHIFT))) {
+		dev_warn(iproc_i2c->device, "bus is busy\n");
+		return -EBUSY;
+	}
+
+	iproc_i2c->msg = msg;
+
+	/* format and load slave address into the TX FIFO */
+	addr = i2c_8bit_addr_from_msg(msg);
+	iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, addr);
+
+	/*
+	 * For a write transaction, load data into the TX FIFO. Only allow
+	 * loading up to TX FIFO size - 1 bytes of data since the first byte
+	 * has been used up by the slave address
+	 */
+	tx_bytes = min_t(unsigned int, msg->len, M_TX_RX_FIFO_SIZE - 1);
+	if (!(msg->flags & I2C_M_RD)) {
+		for (i = 0; i < tx_bytes; i++) {
+			val = msg->buf[i];
+
+			/* mark the last byte */
+			if (!process_call && (i == msg->len - 1))
+				val |= BIT(M_TX_WR_STATUS_SHIFT);
+
+			iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);
+		}
+		iproc_i2c->tx_bytes = tx_bytes;
+	}
+
+	/* Process the read message if this is process call */
+	if (process_call) {
+		msg++;
+		iproc_i2c->msg = msg;  /* point to second msg */
+
+		/*
+		 * The last byte to be sent out should be a slave
+		 * address with read operation
+		 */
+		addr = i2c_8bit_addr_from_msg(msg);
+		/* mark it the last byte out */
+		val = addr | BIT(M_TX_WR_STATUS_SHIFT);
+		iproc_i2c_wr_reg(iproc_i2c, M_TX_OFFSET, val);
+	}
+
+	/* mark as incomplete before starting the transaction */
+	if (iproc_i2c->irq)
+		reinit_completion(&iproc_i2c->done);
+
+	iproc_i2c->xfer_is_done = 0;
+
+	/*
+	 * Enable the "start busy" interrupt, which will be triggered after the
+	 * transaction is done, i.e., the internal start_busy bit, transitions
+	 * from 1 to 0.
+	 */
+	val_intr_en = BIT(IE_M_START_BUSY_SHIFT);
+
+	/*
+	 * If TX data size is larger than the TX FIFO, need to enable TX
+	 * underrun interrupt, which will be triggerred when the TX FIFO is
+	 * empty. When that happens we can then pump more data into the FIFO
+	 */
+	if (!process_call && !(msg->flags & I2C_M_RD) &&
+	    msg->len > iproc_i2c->tx_bytes)
+		val_intr_en |= BIT(IE_M_TX_UNDERRUN_SHIFT);
+
+	/*
+	 * Now we can activate the transfer. For a read operation, specify the
+	 * number of bytes to read
+	 */
+	val = BIT(M_CMD_START_BUSY_SHIFT);
+
+	if (msg->len == 0) {
+		/* SMBUS QUICK Command (Read/Write) */
+		val |= (M_CMD_PROTOCOL_QUICK << M_CMD_PROTOCOL_SHIFT);
+	} else if (msg->flags & I2C_M_RD) {
+		u32 protocol;
+
+		iproc_i2c->rx_bytes = 0;
+		if (msg->len > M_RX_FIFO_MAX_THLD_VALUE)
+			iproc_i2c->thld_bytes = M_RX_FIFO_THLD_VALUE;
+		else
+			iproc_i2c->thld_bytes = msg->len;
+
+		/* set threshold value */
+		tmp = iproc_i2c_rd_reg(iproc_i2c, M_FIFO_CTRL_OFFSET);
+		tmp &= ~(M_FIFO_RX_THLD_MASK << M_FIFO_RX_THLD_SHIFT);
+		tmp |= iproc_i2c->thld_bytes << M_FIFO_RX_THLD_SHIFT;
+		iproc_i2c_wr_reg(iproc_i2c, M_FIFO_CTRL_OFFSET, tmp);
+
+		/* enable the RX threshold interrupt */
+		val_intr_en |= BIT(IE_M_RX_THLD_SHIFT);
+
+		protocol = process_call ?
+				M_CMD_PROTOCOL_PROCESS : M_CMD_PROTOCOL_BLK_RD;
+
+		val |= (protocol << M_CMD_PROTOCOL_SHIFT) |
+		       (msg->len << M_CMD_RD_CNT_SHIFT);
+	} else {
+		val |= (M_CMD_PROTOCOL_BLK_WR << M_CMD_PROTOCOL_SHIFT);
+	}
+
+	if (iproc_i2c->irq)
+		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, val_intr_en);
+
+	return bcm_iproc_i2c_xfer_wait(iproc_i2c, msg, val);
+}
+
+static int bcm_iproc_i2c_xfer(struct i2c_adapter *adapter,
+			      struct i2c_msg msgs[], int num)
+{
+	struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(adapter);
+	bool process_call = false;
+	int ret;
+
+	if (num == 2) {
+		/* Repeated start, use process call */
+		process_call = true;
+		if (msgs[1].flags & I2C_M_NOSTART) {
+			dev_err(iproc_i2c->device, "Invalid repeated start\n");
+			return -EOPNOTSUPP;
+		}
+	}
+
+	ret = bcm_iproc_i2c_xfer_internal(iproc_i2c, msgs, process_call);
+	if (ret) {
+		dev_dbg(iproc_i2c->device, "xfer failed\n");
+		return ret;
+	}
+
+	return num;
+}
+
+static uint32_t bcm_iproc_i2c_functionality(struct i2c_adapter *adap)
+{
+	u32 val;
+
+	val = I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+
+	if (adap->algo->reg_slave)
+		val |= I2C_FUNC_SLAVE;
+
+	return val;
+}
+
+static struct i2c_algorithm bcm_iproc_algo = {
+	.master_xfer = bcm_iproc_i2c_xfer,
+	.functionality = bcm_iproc_i2c_functionality,
+	.reg_slave = bcm_iproc_i2c_reg_slave,
+	.unreg_slave = bcm_iproc_i2c_unreg_slave,
+};
+
+static const struct i2c_adapter_quirks bcm_iproc_i2c_quirks = {
+	.flags = I2C_AQ_COMB_WRITE_THEN_READ,
+	.max_comb_1st_msg_len = M_TX_RX_FIFO_SIZE,
+	.max_read_len = M_RX_MAX_READ_LEN,
+};
+
+static int bcm_iproc_i2c_cfg_speed(struct bcm_iproc_i2c_dev *iproc_i2c)
+{
+	unsigned int bus_speed;
+	u32 val;
+	int ret = of_property_read_u32(iproc_i2c->device->of_node,
+				       "clock-frequency", &bus_speed);
+	if (ret < 0) {
+		dev_info(iproc_i2c->device,
+			"unable to interpret clock-frequency DT property\n");
+		bus_speed = I2C_MAX_STANDARD_MODE_FREQ;
+	}
+
+	if (bus_speed < I2C_MAX_STANDARD_MODE_FREQ) {
+		dev_err(iproc_i2c->device, "%d Hz bus speed not supported\n",
+			bus_speed);
+		dev_err(iproc_i2c->device,
+			"valid speeds are 100khz and 400khz\n");
+		return -EINVAL;
+	} else if (bus_speed < I2C_MAX_FAST_MODE_FREQ) {
+		bus_speed = I2C_MAX_STANDARD_MODE_FREQ;
+	} else {
+		bus_speed = I2C_MAX_FAST_MODE_FREQ;
+	}
+
+	iproc_i2c->bus_speed = bus_speed;
+	val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
+	val &= ~BIT(TIM_CFG_MODE_400_SHIFT);
+	val |= (bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT;
+	iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
+
+	dev_info(iproc_i2c->device, "bus set to %u Hz\n", bus_speed);
+
+	return 0;
+}
+
+static int bcm_iproc_i2c_probe(struct platform_device *pdev)
+{
+	int irq, ret = 0;
+	struct bcm_iproc_i2c_dev *iproc_i2c;
+	struct i2c_adapter *adap;
+	struct resource *res;
+
+	iproc_i2c = devm_kzalloc(&pdev->dev, sizeof(*iproc_i2c),
+				 GFP_KERNEL);
+	if (!iproc_i2c)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, iproc_i2c);
+	iproc_i2c->device = &pdev->dev;
+	iproc_i2c->type =
+		(enum bcm_iproc_i2c_type)of_device_get_match_data(&pdev->dev);
+	init_completion(&iproc_i2c->done);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	iproc_i2c->base = devm_ioremap_resource(iproc_i2c->device, res);
+	if (IS_ERR(iproc_i2c->base))
+		return PTR_ERR(iproc_i2c->base);
+
+	if (iproc_i2c->type == IPROC_I2C_NIC) {
+		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+		iproc_i2c->idm_base = devm_ioremap_resource(iproc_i2c->device,
+							    res);
+		if (IS_ERR(iproc_i2c->idm_base))
+			return PTR_ERR(iproc_i2c->idm_base);
+
+		ret = of_property_read_u32(iproc_i2c->device->of_node,
+					   "brcm,ape-hsls-addr-mask",
+					   &iproc_i2c->ape_addr_mask);
+		if (ret < 0) {
+			dev_err(iproc_i2c->device,
+				"'brcm,ape-hsls-addr-mask' missing\n");
+			return -EINVAL;
+		}
+
+		spin_lock_init(&iproc_i2c->idm_lock);
+
+		/* no slave support */
+		bcm_iproc_algo.reg_slave = NULL;
+		bcm_iproc_algo.unreg_slave = NULL;
+	}
+
+	ret = bcm_iproc_i2c_init(iproc_i2c);
+	if (ret)
+		return ret;
+
+	ret = bcm_iproc_i2c_cfg_speed(iproc_i2c);
+	if (ret)
+		return ret;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq > 0) {
+		ret = devm_request_irq(iproc_i2c->device, irq,
+				       bcm_iproc_i2c_isr, 0, pdev->name,
+				       iproc_i2c);
+		if (ret < 0) {
+			dev_err(iproc_i2c->device,
+				"unable to request irq %i\n", irq);
+			return ret;
+		}
+
+		iproc_i2c->irq = irq;
+	} else {
+		dev_warn(iproc_i2c->device,
+			 "no irq resource, falling back to poll mode\n");
+	}
+
+	bcm_iproc_i2c_enable_disable(iproc_i2c, true);
+
+	adap = &iproc_i2c->adapter;
+	i2c_set_adapdata(adap, iproc_i2c);
+	snprintf(adap->name, sizeof(adap->name),
+		"Broadcom iProc (%s)",
+		of_node_full_name(iproc_i2c->device->of_node));
+	adap->algo = &bcm_iproc_algo;
+	adap->quirks = &bcm_iproc_i2c_quirks;
+	adap->dev.parent = &pdev->dev;
+	adap->dev.of_node = pdev->dev.of_node;
+
+	return i2c_add_adapter(adap);
+}
+
+static int bcm_iproc_i2c_remove(struct platform_device *pdev)
+{
+	struct bcm_iproc_i2c_dev *iproc_i2c = platform_get_drvdata(pdev);
+
+	if (iproc_i2c->irq) {
+		/*
+		 * Make sure there's no pending interrupt when we remove the
+		 * adapter
+		 */
+		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
+		iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
+		synchronize_irq(iproc_i2c->irq);
+	}
+
+	i2c_del_adapter(&iproc_i2c->adapter);
+	bcm_iproc_i2c_enable_disable(iproc_i2c, false);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+
+static int bcm_iproc_i2c_suspend(struct device *dev)
+{
+	struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);
+
+	if (iproc_i2c->irq) {
+		/*
+		 * Make sure there's no pending interrupt when we go into
+		 * suspend
+		 */
+		iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, 0);
+		iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
+		synchronize_irq(iproc_i2c->irq);
+	}
+
+	/* now disable the controller */
+	bcm_iproc_i2c_enable_disable(iproc_i2c, false);
+
+	return 0;
+}
+
+static int bcm_iproc_i2c_resume(struct device *dev)
+{
+	struct bcm_iproc_i2c_dev *iproc_i2c = dev_get_drvdata(dev);
+	int ret;
+	u32 val;
+
+	/*
+	 * Power domain could have been shut off completely in system deep
+	 * sleep, so re-initialize the block here
+	 */
+	ret = bcm_iproc_i2c_init(iproc_i2c);
+	if (ret)
+		return ret;
+
+	/* configure to the desired bus speed */
+	val = iproc_i2c_rd_reg(iproc_i2c, TIM_CFG_OFFSET);
+	val &= ~BIT(TIM_CFG_MODE_400_SHIFT);
+	val |= (iproc_i2c->bus_speed == I2C_MAX_FAST_MODE_FREQ) << TIM_CFG_MODE_400_SHIFT;
+	iproc_i2c_wr_reg(iproc_i2c, TIM_CFG_OFFSET, val);
+
+	bcm_iproc_i2c_enable_disable(iproc_i2c, true);
+
+	return 0;
+}
+
+static const struct dev_pm_ops bcm_iproc_i2c_pm_ops = {
+	.suspend_late = &bcm_iproc_i2c_suspend,
+	.resume_early = &bcm_iproc_i2c_resume
+};
+
+#define BCM_IPROC_I2C_PM_OPS (&bcm_iproc_i2c_pm_ops)
+#else
+#define BCM_IPROC_I2C_PM_OPS NULL
+#endif /* CONFIG_PM_SLEEP */
+
+
+static int bcm_iproc_i2c_reg_slave(struct i2c_client *slave)
+{
+	struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter);
+
+	if (iproc_i2c->slave)
+		return -EBUSY;
+
+	if (slave->flags & I2C_CLIENT_TEN)
+		return -EAFNOSUPPORT;
+
+	iproc_i2c->slave = slave;
+
+	tasklet_init(&iproc_i2c->slave_rx_tasklet, slave_rx_tasklet_fn,
+		     (unsigned long)iproc_i2c);
+
+	bcm_iproc_i2c_slave_init(iproc_i2c, false);
+	return 0;
+}
+
+static int bcm_iproc_i2c_unreg_slave(struct i2c_client *slave)
+{
+	u32 tmp;
+	struct bcm_iproc_i2c_dev *iproc_i2c = i2c_get_adapdata(slave->adapter);
+
+	if (!iproc_i2c->slave)
+		return -EINVAL;
+
+	disable_irq(iproc_i2c->irq);
+
+	tasklet_kill(&iproc_i2c->slave_rx_tasklet);
+
+	/* disable all slave interrupts */
+	tmp = iproc_i2c_rd_reg(iproc_i2c, IE_OFFSET);
+	tmp &= ~(IE_S_ALL_INTERRUPT_MASK <<
+			IE_S_ALL_INTERRUPT_SHIFT);
+	iproc_i2c_wr_reg(iproc_i2c, IE_OFFSET, tmp);
+
+	/* Erase the slave address programmed */
+	tmp = iproc_i2c_rd_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET);
+	tmp &= ~BIT(S_CFG_EN_NIC_SMB_ADDR3_SHIFT);
+	iproc_i2c_wr_reg(iproc_i2c, S_CFG_SMBUS_ADDR_OFFSET, tmp);
+
+	/* flush TX/RX FIFOs */
+	tmp = (BIT(S_FIFO_RX_FLUSH_SHIFT) | BIT(S_FIFO_TX_FLUSH_SHIFT));
+	iproc_i2c_wr_reg(iproc_i2c, S_FIFO_CTRL_OFFSET, tmp);
+
+	/* clear all pending slave interrupts */
+	iproc_i2c_wr_reg(iproc_i2c, IS_OFFSET, ISR_MASK_SLAVE);
+
+	iproc_i2c->slave = NULL;
+
+	enable_irq(iproc_i2c->irq);
+
+	return 0;
+}
+
+static const struct of_device_id bcm_iproc_i2c_of_match[] = {
+	{
+		.compatible = "brcm,iproc-i2c",
+		.data = (int *)IPROC_I2C,
+	}, {
+		.compatible = "brcm,iproc-nic-i2c",
+		.data = (int *)IPROC_I2C_NIC,
+	},
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, bcm_iproc_i2c_of_match);
+
+static struct platform_driver bcm_iproc_i2c_driver = {
+	.driver = {
+		.name = "bcm-iproc-i2c",
+		.of_match_table = bcm_iproc_i2c_of_match,
+		.pm = BCM_IPROC_I2C_PM_OPS,
+	},
+	.probe = bcm_iproc_i2c_probe,
+	.remove = bcm_iproc_i2c_remove,
+};
+module_platform_driver(bcm_iproc_i2c_driver);
+
+MODULE_AUTHOR("Ray Jui <rjui@broadcom.com>");
+MODULE_DESCRIPTION("Broadcom iProc I2C Driver");
+MODULE_LICENSE("GPL v2");