diff --git a/board/it8380dev/board.c b/board/it8380dev/board.c
index 4179dfce19..56fe4d4bcc 100644
--- a/board/it8380dev/board.c
+++ b/board/it8380dev/board.c
@@ -23,6 +23,7 @@
 #include "lpc.h"
 #include "intc.h"
 #include "fan.h"
+#include "i2c.h"
 
 /* Test GPIO interrupt function that toggles one LED. */
 void test_interrupt(enum gpio_signal signal)
@@ -181,6 +182,21 @@ struct keyboard_scan_config keyscan_config = {
 	},
 };
 
+/*
+ * I2C channels (A, B, and C) are using the same timing registers (00h~07h)
+ * at default.
+ * In order to set frequency independently for each channels,
+ * We use timing registers 09h~0Bh, and the supported frequency will be:
+ * 50KHz, 100KHz, 400KHz, or 1MHz.
+ */
+/* I2C ports */
+const struct i2c_port_t i2c_ports[] = {
+	{"battery", 2, 100, GPIO_I2C_C_SCL, GPIO_I2C_C_SDA},
+	{"evb-1",   0, 100, GPIO_I2C_A_SCL, GPIO_I2C_A_SDA},
+	{"evb-2",   1, 100, GPIO_I2C_B_SCL, GPIO_I2C_B_SDA},
+};
+const unsigned int i2c_ports_used = ARRAY_SIZE(i2c_ports);
+
 /*****************************************************************************/
 /* Console commands */
 
diff --git a/board/it8380dev/board.h b/board/it8380dev/board.h
index 4e13c58b86..3207cd0d90 100644
--- a/board/it8380dev/board.h
+++ b/board/it8380dev/board.h
@@ -9,17 +9,18 @@
 #define __CROS_EC_BOARD_H
 
 /* Optional features */
-#define CONFIG_POWER_BUTTON
-#define CONFIG_KEYBOARD_PROTOCOL_8042
-#define CONFIG_KEYBOARD_BOARD_CONFIG
-#undef CONFIG_KEYBOARD_KSI_WUC_INT
-#undef CONFIG_SPI_USE_CS1
-#define CONFIG_PECI_TJMAX 100
-/* For IT839X series and IT838X DX only. */
-#define CONFIG_PECI_WITH_INTERRUPT
-#define CONFIG_FANS 1
 #undef CHIP_FAMILY_IT839X
 
+#define CONFIG_FANS 1
+#undef CONFIG_IT83XX_KEYBOARD_KSI_WUC_INT
+#define CONFIG_IT83XX_PECI_WITH_INTERRUPT
+#define CONFIG_IT83XX_SMCLK2_ON_GPC7
+#undef CONFIG_IT83XX_SPI_USE_CS1
+#define CONFIG_KEYBOARD_BOARD_CONFIG
+#define CONFIG_KEYBOARD_PROTOCOL_8042
+#define CONFIG_PECI_TJMAX 100
+#define CONFIG_POWER_BUTTON
+
 /* Debug */
 #undef CONFIG_KEYBOARD_DEBUG
 #undef CONFIG_UART_TX_BUF_SIZE
diff --git a/board/it8380dev/gpio.inc b/board/it8380dev/gpio.inc
index 4a443c67eb..0e4be968ec 100644
--- a/board/it8380dev/gpio.inc
+++ b/board/it8380dev/gpio.inc
@@ -33,16 +33,35 @@ GPIO(PCH_RCIN_L,     PIN(B, 6), GPIO_OUT_HIGH)
 GPIO(LPC_CLKRUN_L,   PIN(H, 0), GPIO_OUT_LOW)
 GPIO(PCH_WAKE_L,     PIN(B, 7), GPIO_ODR_HIGH) /* Wake signal from EC to PCH */
 
+GPIO(I2C_A_SCL,      PIN(B, 3), GPIO_INPUT)
+GPIO(I2C_A_SDA,      PIN(B, 4), GPIO_INPUT)
+GPIO(I2C_B_SCL,      PIN(C, 1), GPIO_INPUT)
+GPIO(I2C_B_SDA,      PIN(C, 2), GPIO_INPUT)
+#ifdef CONFIG_IT83XX_SMCLK2_ON_GPC7
+GPIO(I2C_C_SCL,      PIN(C, 7), GPIO_INPUT)
+#else
+GPIO(I2C_C_SCL,      PIN(F, 6), GPIO_INPUT)
+#endif
+GPIO(I2C_C_SDA,      PIN(F, 7), GPIO_INPUT)
+
 /* Unimplemented signals which we need to emulate for now */
 UNIMPLEMENTED(ENTERING_RW)
 
 ALTERNATE(PIN_MASK(B, 0x03), 1, MODULE_UART, GPIO_PULL_UP) /* UART0 */
 ALTERNATE(PIN_MASK(A, 0x40), 3, MODULE_SPI, 0)             /* SSCK of SPI */
 ALTERNATE(PIN_MASK(C, 0x28), 3, MODULE_SPI, 0)             /* SMOSI/SMISO of SPI */
-#ifdef CONFIG_SPI_USE_CS1
+#ifdef CONFIG_IT83XX_SPI_USE_CS1
 ALTERNATE(PIN_MASK(G, 0x01), 3, MODULE_SPI, 0)             /* SSCE1# of SPI */
 #else
 ALTERNATE(PIN_MASK(G, 0x04), 3, MODULE_SPI, 0)             /* SSCE0# of SPI */
 #endif
 ALTERNATE(PIN_MASK(A, 0x80), 1, MODULE_PWM_FAN, 0)         /* PWM7 for FAN1 */
 ALTERNATE(PIN_MASK(D, 0x40), 3, MODULE_PWM_FAN, 0)         /* TACH0A for FAN1 */
+ALTERNATE(PIN_MASK(B, 0x18), 1, MODULE_I2C, 0)             /* I2C A SCL/SDA */
+#ifdef CONFIG_IT83XX_SMCLK2_ON_GPC7
+ALTERNATE(PIN_MASK(C, 0x86), 1, MODULE_I2C, 0)             /* I2C B SCL/SDA, C SCL */
+ALTERNATE(PIN_MASK(F, 0x80), 1, MODULE_I2C, 0)             /* I2C C SDA */
+#else
+ALTERNATE(PIN_MASK(C, 0x06), 1, MODULE_I2C, 0)             /* I2C B SCL/SDA */
+ALTERNATE(PIN_MASK(F, 0xC0), 1, MODULE_I2C, 0)             /* I2C C SCL/SDA */
+#endif
diff --git a/chip/it83xx/build.mk b/chip/it83xx/build.mk
index 280c6c5de8..d8e75f0726 100644
--- a/chip/it83xx/build.mk
+++ b/chip/it83xx/build.mk
@@ -24,3 +24,4 @@ chip-$(CONFIG_LPC)+=lpc.o
 chip-$(CONFIG_SPI)+=spi.o
 chip-$(CONFIG_PECI)+=peci.o
 chip-$(HAS_TASK_KEYSCAN)+=keyboard_raw.o
+chip-$(CONFIG_I2C)+=i2c.o
diff --git a/chip/it83xx/config_chip.h b/chip/it83xx/config_chip.h
index 6ec6fbee4c..b38decefdc 100644
--- a/chip/it83xx/config_chip.h
+++ b/chip/it83xx/config_chip.h
@@ -22,6 +22,9 @@
 /* Default PLL frequency. */
 #define PLL_CLOCK 48000000
 
+/* Number of I2C ports */
+#define I2C_PORT_COUNT 3
+
 /****************************************************************************/
 /* Memory mapping */
 
@@ -76,15 +79,15 @@
 #define CONFIG_HW_SPECIFIC_UDELAY
 
 /* Optional features present on this chip */
-#undef CONFIG_I2C
-#undef CONFIG_FLASH
-#undef CONFIG_WATCHDOG
-#define CONFIG_PWM
 #define CONFIG_ADC
 #define CONFIG_EC2I
+#undef CONFIG_FLASH
+#define CONFIG_I2C
 #define CONFIG_LPC
-#define CONFIG_SPI
 #define CONFIG_PECI
+#define CONFIG_PWM
+#define CONFIG_SPI
+#undef CONFIG_WATCHDOG
 
 #define GPIO_PIN(port, index) GPIO_##port, (1 << index)
 #define GPIO_PIN_MASK(port, mask) GPIO_##port, (mask)
diff --git a/chip/it83xx/gpio.c b/chip/it83xx/gpio.c
index 49c31fb871..24ef6ac78d 100644
--- a/chip/it83xx/gpio.c
+++ b/chip/it83xx/gpio.c
@@ -360,7 +360,7 @@ static void __gpio_irq(void)
 	/* Determine interrupt number. */
 	int irq = IT83XX_INTC_IVCT2 - 16;
 
-#if defined(HAS_TASK_KEYSCAN) && defined(CONFIG_KEYBOARD_KSI_WUC_INT)
+#if defined(HAS_TASK_KEYSCAN) && defined(CONFIG_IT83XX_KEYBOARD_KSI_WUC_INT)
 	if (irq == IT83XX_IRQ_WKINTC) {
 		keyboard_raw_interrupt();
 		return;
diff --git a/chip/it83xx/i2c.c b/chip/it83xx/i2c.c
new file mode 100644
index 0000000000..e76228f428
--- /dev/null
+++ b/chip/it83xx/i2c.c
@@ -0,0 +1,468 @@
+/* Copyright 2015 The Chromium OS Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+/* I2C module for Chrome EC */
+
+#include "clock.h"
+#include "common.h"
+#include "console.h"
+#include "gpio.h"
+#include "hooks.h"
+#include "i2c.h"
+#include "registers.h"
+#include "task.h"
+#include "timer.h"
+#include "util.h"
+
+#define CPRINTS(format, args...) cprints(CC_I2C, format, ## args)
+
+/*
+ * The count number of the counter for 25 ms register.
+ * The 25 ms register is calculated by (count number *1.024 kHz).
+ */
+#define I2C_CLK_LOW_TIMEOUT  25 /* ~= 25ms */
+
+#define I2C_LOOP_DELAY_US    16
+
+/* Default maximum time we allow for an I2C transfer */
+#define I2C_TIMEOUT_DEFAULT_US (100 * MSEC)
+
+enum i2c_host_status {
+	/* Host busy */
+	HOSTA_HOBY = 0x01,
+	/* Finish Interrupt */
+	HOSTA_FINTR = 0x02,
+	/* Device error */
+	HOSTA_DVER = 0x04,
+	/* Bus error */
+	HOSTA_BSER = 0x08,
+	/* Fail */
+	HOSTA_FAIL = 0x10,
+	/* Not response ACK */
+	HOSTA_NACK = 0x20,
+	/* Time-out error */
+	HOSTA_TMOE = 0x40,
+	/* Byte done status */
+	HOSTA_BDS = 0x80,
+
+	HOSTA_NO_FINISH = 0xFF,
+};
+
+enum i2c_host_status_mask {
+	HOSTA_ANY_ERROR = (HOSTA_DVER | HOSTA_BSER |
+				HOSTA_FAIL | HOSTA_NACK | HOSTA_TMOE),
+	HOSTA_NEXT_BYTE = HOSTA_BDS,
+	HOSTA_ALL_WC_BIT = (HOSTA_FINTR | HOSTA_ANY_ERROR | HOSTA_BDS),
+};
+
+enum i2c_reset_cause {
+	I2C_RC_NO_IDLE_FOR_START = 1,
+	I2C_RC_READ_NO_FINISH,
+	I2C_RC_WRITE_NO_FINISH,
+};
+
+struct i2c_ch_freq {
+	int kpbs;
+	uint8_t freq_set;
+};
+
+static const struct i2c_ch_freq i2c_freq_select[] = {
+	{ 50,   1},
+	{ 100,  2},
+	{ 400,  3},
+	{ 1000, 4},
+};
+
+struct i2c_pin {
+	volatile uint8_t *pin_clk;
+	volatile uint8_t *pin_data;
+	volatile uint8_t *pin_clk_ctrl;
+	volatile uint8_t *pin_data_ctrl;
+	volatile uint8_t *mirror_clk;
+	volatile uint8_t *mirror_data;
+	uint8_t clk_mask;
+	uint8_t data_mask;
+};
+
+static const struct i2c_pin i2c_pin_regs[] = {
+	{ &IT83XX_GPIO_GPCRB3, &IT83XX_GPIO_GPCRB4,
+		&IT83XX_GPIO_GPDRB, &IT83XX_GPIO_GPDRB,
+		&IT83XX_GPIO_GPDMRB, &IT83XX_GPIO_GPDMRB,
+		0x08, 0x10},
+	{ &IT83XX_GPIO_GPCRC1, &IT83XX_GPIO_GPCRC2,
+		&IT83XX_GPIO_GPDRC, &IT83XX_GPIO_GPDRC,
+		&IT83XX_GPIO_GPDMRC, &IT83XX_GPIO_GPDMRC,
+		0x02, 0x04},
+#ifdef CONFIG_IT83XX_SMCLK2_ON_GPC7
+	{ &IT83XX_GPIO_GPCRC7, &IT83XX_GPIO_GPCRF7,
+		&IT83XX_GPIO_GPDRC, &IT83XX_GPIO_GPDRF,
+		&IT83XX_GPIO_GPDMRC, &IT83XX_GPIO_GPDMRF,
+		0x80, 0x80},
+#else
+	{ &IT83XX_GPIO_GPCRF6, &IT83XX_GPIO_GPCRF7,
+		&IT83XX_GPIO_GPDRF, &IT83XX_GPIO_GPDRF,
+		&IT83XX_GPIO_GPDMRF, &IT83XX_GPIO_GPDMRF,
+		0x40, 0x80},
+#endif
+};
+
+/* I2C port state data */
+struct i2c_port_data {
+	const uint8_t *out;  /* Output data pointer */
+	int out_size;        /* Output data to transfer, in bytes */
+	uint8_t *in;         /* Input data pointer */
+	int in_size;         /* Input data to transfer, in bytes */
+	int flags;           /* Flags (I2C_XFER_*) */
+	int widx;            /* Index into output data */
+	int ridx;            /* Index into input data */
+	int err;             /* Error code, if any */
+	uint8_t addr;        /* address of device */
+	uint32_t timeout_us; /* Transaction timeout, or 0 to use default */
+};
+static struct i2c_port_data pdata[I2C_PORT_COUNT];
+
+static void i2c_reset(int p, int cause)
+{
+	/* bit1, kill current transaction. */
+	IT83XX_SMB_HOCTL(p) |= 0x02;
+	IT83XX_SMB_HOCTL(p) &= ~0x02;
+
+	/* Disable the SMBus host interface */
+	IT83XX_SMB_HOCTL2(p) = 0x00;
+
+	/* clk pin output high */
+	*i2c_pin_regs[p].pin_clk = 0x40;
+	*i2c_pin_regs[p].pin_clk_ctrl |= i2c_pin_regs[p].clk_mask;
+
+	udelay(16);
+
+	/* data pin output high */
+	*i2c_pin_regs[p].pin_data = 0x40;
+	*i2c_pin_regs[p].pin_data_ctrl |= i2c_pin_regs[p].data_mask;
+
+	udelay(500);
+	/* start condition */
+	*i2c_pin_regs[p].pin_data_ctrl &= ~i2c_pin_regs[p].data_mask;
+	udelay(1000);
+	/* stop condition */
+	*i2c_pin_regs[p].pin_data_ctrl |= i2c_pin_regs[p].data_mask;
+	udelay(500);
+
+	/* I2C function */
+	*i2c_pin_regs[p].pin_clk = 0x00;
+	*i2c_pin_regs[p].pin_data = 0x00;
+
+	/* Enable the SMBus host interface */
+	IT83XX_SMB_HOCTL2(p) = 0x11;
+
+	/* W/C host status register */
+	IT83XX_SMB_HOSTA(p) = HOSTA_ALL_WC_BIT;
+
+	CPRINTS("I2C ch%d reset cause %d", p, cause);
+}
+
+static void i2c_r_last_byte(int p)
+{
+	struct i2c_port_data *pd = pdata + p;
+
+	/*
+	 * bit5, The firmware shall write 1 to this bit
+	 * when the next byte will be the last byte for i2c read.
+	 */
+	if ((pd->flags & I2C_XFER_STOP) && (pd->ridx == pd->in_size - 1))
+		IT83XX_SMB_HOCTL(p) |= 0x20;
+}
+
+static void i2c_w2r_change_direction(int p)
+{
+	/* I2C switch direction */
+	if (IT83XX_SMB_HOCTL2(p) & 0x08) {
+		i2c_r_last_byte(p);
+		IT83XX_SMB_HOSTA(p) = HOSTA_NEXT_BYTE;
+	} else {
+		/*
+		 * bit2, I2C switch direction wait.
+		 * bit3, I2C switch direction enable.
+		 */
+		IT83XX_SMB_HOCTL2(p) |= 0x0C;
+		IT83XX_SMB_HOSTA(p) = HOSTA_NEXT_BYTE;
+		i2c_r_last_byte(p);
+		IT83XX_SMB_HOCTL2(p) &= ~0x04;
+	}
+}
+
+static int i2c_transaction(int p)
+{
+	uint32_t num;
+	struct i2c_port_data *pd = pdata + p;
+
+	/* i2c write */
+	if (pd->out_size) {
+		if (pd->flags & I2C_XFER_START) {
+			/* i2c enable */
+			IT83XX_SMB_HOCTL2(p) = 0x13;
+			/*
+			 * bit0, Direction of the host transfer.
+			 * bit[1:7}, Address of the targeted slave.
+			 */
+			IT83XX_SMB_TRASLA(p) = pd->addr;
+			/* Send first byte */
+			IT83XX_SMB_HOBDB(p) = *(pd->out++);
+			pd->widx++;
+			/*
+			 * bit0, Host interrupt enable.
+			 * bit[2:4}, Extend command.
+			 * bit6, start.
+			 */
+			IT83XX_SMB_HOCTL(p) = 0x5D;
+		}
+
+		for (num = 0; num < pd->timeout_us; num += I2C_LOOP_DELAY_US) {
+			/* Host has completed the transmission of a byte */
+			if (IT83XX_SMB_HOSTA(p) & HOSTA_BDS) {
+				if (pd->widx < pd->out_size) {
+					/* Send next byte */
+					IT83XX_SMB_HOBDB(p) = *(pd->out++);
+					pd->widx++;
+				} else {
+					if (pd->in_size > 0) {
+						i2c_w2r_change_direction(p);
+						goto write_to_read;
+					}
+
+					if (pd->flags & I2C_XFER_STOP)
+						IT83XX_SMB_HOCTL2(p) = 0x11;
+					else
+						break;
+				}
+				/* W/C byte done for next byte or finish */
+				IT83XX_SMB_HOSTA(p) = HOSTA_NEXT_BYTE;
+			/* This bit will be set by termination of a command */
+			} else if (IT83XX_SMB_HOSTA(p) & HOSTA_FINTR) {
+				break;
+			}
+			/* - 1 since some time was used in the code above */
+			udelay(I2C_LOOP_DELAY_US - 1);
+		}
+
+		pd->err = IT83XX_SMB_HOSTA(p) & HOSTA_ANY_ERROR;
+
+		if (num > pd->timeout_us) {
+			pd->err = HOSTA_NO_FINISH;
+			i2c_reset(p, I2C_RC_WRITE_NO_FINISH);
+		}
+
+		if (pd->flags & I2C_XFER_STOP) {
+			IT83XX_SMB_HOCTL2(p) = 0x00;
+			/* W/C */
+			IT83XX_SMB_HOSTA(p) = HOSTA_ALL_WC_BIT;
+		}
+		return pd->err;
+	/* i2c read */
+	} else if (pd->in_size) {
+		if (pd->flags & I2C_XFER_START) {
+			/* i2c enable */
+			IT83XX_SMB_HOCTL2(p) = 0x13;
+			/*
+			 * bit0, Direction of the host transfer.
+			 * bit[1:7}, Address of the targeted slave.
+			 */
+			IT83XX_SMB_TRASLA(p) = pd->addr | 0x01;
+			/*
+			 * bit0, Host interrupt enable.
+			 * bit[2:4}, Extend command.
+			 * bit5, The firmware shall write 1 to this bit
+			 *       when the next byte will be the last byte.
+			 * bit6, start.
+			 */
+			if ((1 == pd->in_size) && (pd->flags & I2C_XFER_STOP))
+				IT83XX_SMB_HOCTL(p) = 0x7D;
+			else
+				IT83XX_SMB_HOCTL(p) = 0x5D;
+		} else {
+			i2c_w2r_change_direction(p);
+		}
+
+write_to_read:
+		for (num = 0; num < pd->timeout_us; num += I2C_LOOP_DELAY_US) {
+			/* when the host controller has received a byte */
+			if (IT83XX_SMB_HOSTA(p) & HOSTA_BDS) {
+				if (pd->ridx < pd->in_size) {
+					/* To get received data. */
+					*(pd->in++) = IT83XX_SMB_HOBDB(p);
+					pd->ridx++;
+					/* For last byte */
+					i2c_r_last_byte(p);
+				}
+
+				if ((pd->ridx == pd->in_size) &&
+					(!(pd->flags & I2C_XFER_STOP)))
+					break;
+
+				/* W/C for next byte or finish */
+				IT83XX_SMB_HOSTA(p) = HOSTA_NEXT_BYTE;
+			/* This bit will be set by termination of a command */
+			} else if (IT83XX_SMB_HOSTA(p) & HOSTA_FINTR) {
+				break;
+			}
+
+			/* - 1 since some time was used in the code above */
+			udelay(I2C_LOOP_DELAY_US - 1);
+		}
+
+		pd->err = IT83XX_SMB_HOSTA(p) & HOSTA_ANY_ERROR;
+
+		if (num > pd->timeout_us) {
+			pd->err = HOSTA_NO_FINISH;
+			i2c_reset(p, I2C_RC_READ_NO_FINISH);
+		}
+
+		if (pd->flags & I2C_XFER_STOP) {
+			IT83XX_SMB_HOCTL2(p) = 0x00;
+			/* W/C */
+			IT83XX_SMB_HOSTA(p) = HOSTA_ALL_WC_BIT;
+		}
+		return pd->err;
+	}
+	return 0;
+}
+
+int i2c_is_busy(int port)
+{
+	return IT83XX_SMB_HOSTA(port) & HOSTA_HOBY;
+}
+
+int chip_i2c_xfer(int port, int slave_addr, const uint8_t *out, int out_size,
+	     uint8_t *in, int in_size, int flags)
+{
+	struct i2c_port_data *pd = pdata + port;
+
+	if (out_size == 0 && in_size == 0)
+		return EC_SUCCESS;
+
+	/* Copy data to port struct */
+	pd->out = out;
+	pd->out_size = out_size;
+	pd->in = in;
+	pd->in_size = in_size;
+	pd->flags = flags;
+	pd->widx = 0;
+	pd->ridx = 0;
+	pd->err = 0;
+	pd->addr = slave_addr;
+
+	/* Make sure we're in a good state to start */
+	if ((flags & I2C_XFER_START) && (i2c_is_busy(port)
+			|| (IT83XX_SMB_HOSTA(port) & HOSTA_ALL_WC_BIT)
+			|| (i2c_get_line_levels(port) != I2C_LINE_IDLE))) {
+		/* Attempt to unwedge the port. */
+		i2c_unwedge(port);
+		/* reset i2c port */
+		i2c_reset(port, I2C_RC_NO_IDLE_FOR_START);
+	}
+	/* Start transaction */
+	i2c_transaction(port);
+
+	return pd->err;
+}
+
+int i2c_raw_get_scl(int port)
+{
+	enum gpio_signal g;
+
+	if (get_scl_from_i2c_port(port, &g) == EC_SUCCESS)
+		return !!(*i2c_pin_regs[port].mirror_clk &
+			i2c_pin_regs[port].clk_mask);
+
+	/* If no SCL pin defined for this port, then return 1 to appear idle */
+	return 1;
+}
+
+int i2c_raw_get_sda(int port)
+{
+	enum gpio_signal g;
+
+	if (get_sda_from_i2c_port(port, &g) == EC_SUCCESS)
+		return !!(*i2c_pin_regs[port].mirror_data &
+			i2c_pin_regs[port].data_mask);
+
+	/* If no SDA pin defined for this port, then return 1 to appear idle */
+	return 1;
+}
+
+int i2c_get_line_levels(int port)
+{
+	return IT83XX_SMB_SMBPCTL(port) & 0x03;
+}
+
+void i2c_set_timeout(int port, uint32_t timeout)
+{
+	pdata[port].timeout_us = timeout ? timeout : I2C_TIMEOUT_DEFAULT_US;
+}
+
+static void i2c_freq_changed(void)
+{
+	int i, f;
+
+	for (i = 0; i < i2c_ports_used; i++) {
+		for (f = ARRAY_SIZE(i2c_freq_select) - 1; f >= 0; f--) {
+			if (i2c_ports[i].kbps >= i2c_freq_select[f].kpbs) {
+				IT83XX_SMB_SCLKTS(i2c_ports[i].port) =
+					i2c_freq_select[f].freq_set;
+				break;
+			}
+		}
+	}
+
+	/* This field defines the SMCLK0/1/2 clock/data low timeout. */
+	IT83XX_SMB_25MS = I2C_CLK_LOW_TIMEOUT;
+}
+DECLARE_HOOK(HOOK_FREQ_CHANGE, i2c_freq_changed, HOOK_PRIO_DEFAULT);
+
+static void i2c_init(void)
+{
+	int i, p;
+
+	/* Configure GPIOs */
+	gpio_config_module(MODULE_I2C, 1);
+
+#ifdef CONFIG_IT83XX_SMCLK2_ON_GPC7
+	/* bit7, 0: SMCLK2 is located on GPF6, 1: SMCLK2 is located on GPC7 */
+	IT83XX_GPIO_GRC7 |= 0x80;
+#endif
+
+	/* Enable I2C function. */
+	for (i = 0; i < i2c_ports_used; i++) {
+		/* I2c port mapping. */
+		p = i2c_ports[i].port;
+		/*
+		 * bit0, The SMBus host interface is enabled.
+		 * bit1, Enable to communicate with I2C device and
+		 *       support I2C-compatible cycles.
+		 * bit4, This bit controls the reset mechanism of SMBus master
+		 *       to handle the SMDAT line low if 25ms reg timeout.
+		 */
+		IT83XX_SMB_HOCTL2(p) = 0x11;
+		/*
+		 * bit1, Kill SMBus host transaction.
+		 * bit0, Enable the interrupt for the master interface.
+		 */
+		IT83XX_SMB_HOCTL(p) = 0x03;
+		IT83XX_SMB_HOCTL(p) = 0x01;
+		/* W/C host status register */
+		IT83XX_SMB_HOSTA(p) = HOSTA_ALL_WC_BIT;
+
+		IT83XX_SMB_HOCTL2(p) = 0x00;
+	}
+
+	i2c_freq_changed();
+
+	for (i = 0; i < I2C_PORT_COUNT; i++) {
+
+		/* Use default timeout */
+		i2c_set_timeout(i, 0);
+	}
+}
+DECLARE_HOOK(HOOK_INIT, i2c_init, HOOK_PRIO_INIT_I2C);
diff --git a/chip/it83xx/intc.c b/chip/it83xx/intc.c
index b4f42b0ab4..ebccb043d1 100644
--- a/chip/it83xx/intc.c
+++ b/chip/it83xx/intc.c
@@ -24,7 +24,7 @@ void intc_cpu_int_group_5(void)
 		lpc_kbc_ibf_interrupt();
 		break;
 #endif
-#if defined(HAS_TASK_KEYSCAN) && !defined(CONFIG_KEYBOARD_KSI_WUC_INT)
+#if defined(HAS_TASK_KEYSCAN) && !defined(CONFIG_IT83XX_KEYBOARD_KSI_WUC_INT)
 	case IT83XX_IRQ_KB_MATRIX:
 		keyboard_raw_interrupt();
 		break;
diff --git a/chip/it83xx/keyboard_raw.c b/chip/it83xx/keyboard_raw.c
index 48749008d2..ddaa4974e2 100644
--- a/chip/it83xx/keyboard_raw.c
+++ b/chip/it83xx/keyboard_raw.c
@@ -35,7 +35,7 @@ void keyboard_raw_init(void)
 	/* KSO[15:8] pins low. */
 	IT83XX_KBS_KSOH1 = 0x00;
 
-#ifdef CONFIG_KEYBOARD_KSI_WUC_INT
+#ifdef CONFIG_IT83XX_KEYBOARD_KSI_WUC_INT
 	/* KSI[0-7] falling-edge triggered is selected */
 	IT83XX_WUC_WUEMR3 = 0xFF;
 
@@ -58,7 +58,7 @@ void keyboard_raw_init(void)
  */
 void keyboard_raw_task_start(void)
 {
-#ifdef CONFIG_KEYBOARD_KSI_WUC_INT
+#ifdef CONFIG_IT83XX_KEYBOARD_KSI_WUC_INT
 	IT83XX_WUC_WUESR3 = 0xFF;
 	task_clear_pending_irq(IT83XX_IRQ_WKINTC);
 	task_enable_irq(IT83XX_IRQ_WKINTC);
@@ -105,7 +105,7 @@ test_mockable int keyboard_raw_read_rows(void)
 void keyboard_raw_enable_interrupt(int enable)
 {
 	if (enable) {
-#ifdef CONFIG_KEYBOARD_KSI_WUC_INT
+#ifdef CONFIG_IT83XX_KEYBOARD_KSI_WUC_INT
 		IT83XX_WUC_WUESR3 = 0xFF;
 		task_clear_pending_irq(IT83XX_IRQ_WKINTC);
 		task_enable_irq(IT83XX_IRQ_WKINTC);
@@ -114,7 +114,7 @@ void keyboard_raw_enable_interrupt(int enable)
 		task_enable_irq(IT83XX_IRQ_KB_MATRIX);
 #endif
 	} else {
-#ifdef CONFIG_KEYBOARD_KSI_WUC_INT
+#ifdef CONFIG_IT83XX_KEYBOARD_KSI_WUC_INT
 		task_disable_irq(IT83XX_IRQ_WKINTC);
 #else
 		task_disable_irq(IT83XX_IRQ_KB_MATRIX);
@@ -127,7 +127,7 @@ void keyboard_raw_enable_interrupt(int enable)
  */
 void keyboard_raw_interrupt(void)
 {
-#ifdef CONFIG_KEYBOARD_KSI_WUC_INT
+#ifdef CONFIG_IT83XX_KEYBOARD_KSI_WUC_INT
 	task_disable_irq(IT83XX_IRQ_WKINTC);
 #else
 	task_disable_irq(IT83XX_IRQ_KB_MATRIX);
diff --git a/chip/it83xx/peci.c b/chip/it83xx/peci.c
index b613fa7971..1f167b3f43 100644
--- a/chip/it83xx/peci.c
+++ b/chip/it83xx/peci.c
@@ -182,7 +182,7 @@ static enum peci_status peci_transaction(uint8_t addr,
 		IT83XX_PECI_HOWRDR = w_buf[index];
 
 	peci_current_task = task_get_current();
-#ifdef CONFIG_PECI_WITH_INTERRUPT
+#ifdef CONFIG_IT83XX_PECI_WITH_INTERRUPT
 	task_clear_pending_irq(IT83XX_IRQ_PECI);
 	task_enable_irq(IT83XX_IRQ_PECI);
 
diff --git a/chip/it83xx/registers.h b/chip/it83xx/registers.h
index bc7ddeee44..47113ecd12 100644
--- a/chip/it83xx/registers.h
+++ b/chip/it83xx/registers.h
@@ -461,6 +461,10 @@
 
 #define IT83XX_GPIO_GCR         REG8(IT83XX_GPIO_BASE+0x00)
 
+#define IT83XX_GPIO_GPDRB       REG8(IT83XX_GPIO_BASE+0x02)
+#define IT83XX_GPIO_GPDRC       REG8(IT83XX_GPIO_BASE+0x03)
+#define IT83XX_GPIO_GPDRF       REG8(IT83XX_GPIO_BASE+0x06)
+
 #define IT83XX_GPIO_GPCRA0      REG8(IT83XX_GPIO_BASE+0x10)
 #define IT83XX_GPIO_GPCRA1      REG8(IT83XX_GPIO_BASE+0x11)
 #define IT83XX_GPIO_GPCRA2      REG8(IT83XX_GPIO_BASE+0x12)
@@ -470,6 +474,33 @@
 #define IT83XX_GPIO_GPCRA6      REG8(IT83XX_GPIO_BASE+0x16)
 #define IT83XX_GPIO_GPCRA7      REG8(IT83XX_GPIO_BASE+0x17)
 
+#define IT83XX_GPIO_GPCRB0      REG8(IT83XX_GPIO_BASE+0x18)
+#define IT83XX_GPIO_GPCRB1      REG8(IT83XX_GPIO_BASE+0x19)
+#define IT83XX_GPIO_GPCRB2      REG8(IT83XX_GPIO_BASE+0x1A)
+#define IT83XX_GPIO_GPCRB3      REG8(IT83XX_GPIO_BASE+0x1B)
+#define IT83XX_GPIO_GPCRB4      REG8(IT83XX_GPIO_BASE+0x1C)
+#define IT83XX_GPIO_GPCRB5      REG8(IT83XX_GPIO_BASE+0x1D)
+#define IT83XX_GPIO_GPCRB6      REG8(IT83XX_GPIO_BASE+0x1E)
+#define IT83XX_GPIO_GPCRB7      REG8(IT83XX_GPIO_BASE+0x1F)
+
+#define IT83XX_GPIO_GPCRC0      REG8(IT83XX_GPIO_BASE+0x20)
+#define IT83XX_GPIO_GPCRC1      REG8(IT83XX_GPIO_BASE+0x21)
+#define IT83XX_GPIO_GPCRC2      REG8(IT83XX_GPIO_BASE+0x22)
+#define IT83XX_GPIO_GPCRC3      REG8(IT83XX_GPIO_BASE+0x23)
+#define IT83XX_GPIO_GPCRC4      REG8(IT83XX_GPIO_BASE+0x24)
+#define IT83XX_GPIO_GPCRC5      REG8(IT83XX_GPIO_BASE+0x25)
+#define IT83XX_GPIO_GPCRC6      REG8(IT83XX_GPIO_BASE+0x26)
+#define IT83XX_GPIO_GPCRC7      REG8(IT83XX_GPIO_BASE+0x27)
+
+#define IT83XX_GPIO_GPCRF0      REG8(IT83XX_GPIO_BASE+0x38)
+#define IT83XX_GPIO_GPCRF1      REG8(IT83XX_GPIO_BASE+0x39)
+#define IT83XX_GPIO_GPCRF2      REG8(IT83XX_GPIO_BASE+0x3A)
+#define IT83XX_GPIO_GPCRF3      REG8(IT83XX_GPIO_BASE+0x3B)
+#define IT83XX_GPIO_GPCRF4      REG8(IT83XX_GPIO_BASE+0x3C)
+#define IT83XX_GPIO_GPCRF5      REG8(IT83XX_GPIO_BASE+0x3D)
+#define IT83XX_GPIO_GPCRF6      REG8(IT83XX_GPIO_BASE+0x3E)
+#define IT83XX_GPIO_GPCRF7      REG8(IT83XX_GPIO_BASE+0x3F)
+
 #define IT83XX_GPIO_GPCRF0      REG8(IT83XX_GPIO_BASE+0x38)
 #define IT83XX_GPIO_GPCRF1      REG8(IT83XX_GPIO_BASE+0x39)
 #define IT83XX_GPIO_GPCRF2      REG8(IT83XX_GPIO_BASE+0x3A)
@@ -488,6 +519,10 @@
 #define IT83XX_GPIO_GPCRI6      REG8(IT83XX_GPIO_BASE+0x56)
 #define IT83XX_GPIO_GPCRI7      REG8(IT83XX_GPIO_BASE+0x57)
 
+#define IT83XX_GPIO_GPDMRB      REG8(IT83XX_GPIO_BASE+0x62)
+#define IT83XX_GPIO_GPDMRC      REG8(IT83XX_GPIO_BASE+0x63)
+#define IT83XX_GPIO_GPDMRF      REG8(IT83XX_GPIO_BASE+0x66)
+
 #define IT83XX_GPIO_GRC1        REG8(IT83XX_GPIO_BASE+0xF0)
 #define IT83XX_GPIO_GRC2        REG8(IT83XX_GPIO_BASE+0xF1)
 #define IT83XX_GPIO_GRC3        REG8(IT83XX_GPIO_BASE+0xF2)
@@ -856,12 +891,34 @@ REG8(IT83XX_PMC_BASE + (ch > LPC_PM2 ? 3 : 6) + (ch << 4))
 #define IT83XX_PECI_AWFCSV      REG8(IT83XX_PECI_BASE+0x0D)
 #define IT83XX_PECI_PADCTLR     REG8(IT83XX_PECI_BASE+0x0E)
 
+/* SMBus/I2C Interface (SMB/I2C) */
+#define IT83XX_SMB_BASE   0x00F01C00
+
+#define IT83XX_SMB_4P7USL       REG8(IT83XX_SMB_BASE+0x00)
+#define IT83XX_SMB_4P0USL       REG8(IT83XX_SMB_BASE+0x01)
+#define IT83XX_SMB_300NS        REG8(IT83XX_SMB_BASE+0x02)
+#define IT83XX_SMB_250NS        REG8(IT83XX_SMB_BASE+0x03)
+#define IT83XX_SMB_25MS         REG8(IT83XX_SMB_BASE+0x04)
+#define IT83XX_SMB_45P3USL      REG8(IT83XX_SMB_BASE+0x05)
+#define IT83XX_SMB_45P3USH      REG8(IT83XX_SMB_BASE+0x06)
+#define IT83XX_SMB_4P7A4P0H     REG8(IT83XX_SMB_BASE+0x07)
+#define IT83XX_SMB_SCLKTS(ch)   REG8(IT83XX_SMB_BASE+0x09+ch)
+#define IT83XX_SMB_HOSTA(ch)    REG8(IT83XX_SMB_BASE+0x40+(ch << 6))
+#define IT83XX_SMB_HOCTL(ch)    REG8(IT83XX_SMB_BASE+0x41+(ch << 6))
+#define IT83XX_SMB_HOCMD(ch)    REG8(IT83XX_SMB_BASE+0x42+(ch << 6))
+#define IT83XX_SMB_TRASLA(ch)   REG8(IT83XX_SMB_BASE+0x43+(ch << 6))
+#define IT83XX_SMB_D0REG(ch)    REG8(IT83XX_SMB_BASE+0x44+(ch << 6))
+#define IT83XX_SMB_D1REG(ch)    REG8(IT83XX_SMB_BASE+0x45+(ch << 6))
+#define IT83XX_SMB_HOBDB(ch)    REG8(IT83XX_SMB_BASE+0x46+(ch << 6))
+#define IT83XX_SMB_PECERC(ch)   REG8(IT83XX_SMB_BASE+0x47+(ch << 6))
+#define IT83XX_SMB_SMBPCTL(ch)  REG8(IT83XX_SMB_BASE+0x4A+(ch << 6))
+#define IT83XX_SMB_HOCTL2(ch)   REG8(IT83XX_SMB_BASE+0x50+(ch << 6))
+
 /* --- MISC (not implemented yet) --- */
 
 #define IT83XX_PS2_BASE   0x00F01700
 #define IT83XX_DAC_BASE   0x00F01A00
 #define IT83XX_WUC_BASE   0x00F01B00
-#define IT83XX_SMB_BASE   0x00F01C00
 #define IT83XX_EGPIO_BASE 0x00F02100
 #define IT83XX_BRAM_BASE  0x00F02200
 #define IT83XX_CIR_BASE   0x00F02300
diff --git a/chip/it83xx/spi.c b/chip/it83xx/spi.c
index 503e4a8d41..12955c80e3 100644
--- a/chip/it83xx/spi.c
+++ b/chip/it83xx/spi.c
@@ -82,7 +82,7 @@ int spi_enable(int enable)
 		 * 01b: SSCK/SMOSI/SMISO/SSCE0# are enabled.
 		 * 11b: SSCK/SMOSI/SMISO/SSCE1#/SSCE0# are enabled.
 		 */
-#ifdef CONFIG_SPI_USE_CS1
+#ifdef CONFIG_IT83XX_SPI_USE_CS1
 		IT83XX_GPIO_GRC1 |= 0x20;
 #else
 		IT83XX_GPIO_GRC1 |= 0x10;
@@ -105,7 +105,7 @@ int spi_transaction(const uint8_t *txdata, int txlen,
 	IT83XX_SSPI_SPICTRL2 &= ~0x04;
 	for (idx = 0x00; idx < txlen; idx++) {
 		IT83XX_SSPI_SPIDATA = txdata[idx];
-#ifdef CONFIG_SPI_USE_CS1
+#ifdef CONFIG_IT83XX_SPI_USE_CS1
 		/* Write 1 to start the data transmission of CS1 */
 		IT83XX_SSPI_SPISTS |= 0x08;
 #else
@@ -117,7 +117,7 @@ int spi_transaction(const uint8_t *txdata, int txlen,
 	/* bit[1]: Read cycle */
 	IT83XX_SSPI_SPICTRL2 |= 0x04;
 	for (idx = 0x00; idx < rxlen; idx++) {
-#ifdef CONFIG_SPI_USE_CS1
+#ifdef CONFIG_IT83XX_SPI_USE_CS1
 		/* Write 1 to start the data transmission of CS1 */
 		IT83XX_SSPI_SPISTS |= 0x08;
 #else
diff --git a/include/config.h b/include/config.h
index be4d59127c..f7af2ba28b 100644
--- a/include/config.h
+++ b/include/config.h
@@ -935,6 +935,18 @@
 /* Number of IRQs supported on the EC chip */
 #undef CONFIG_IRQ_COUNT
 
+/* Enable Wake-up control interrupt from KSI */
+#undef CONFIG_IT83XX_KEYBOARD_KSI_WUC_INT
+
+/* Interrupt for PECI module. (IT839X series and IT838X DX only) */
+#undef CONFIG_IT83XX_PECI_WITH_INTERRUPT
+
+/* To define it, if I2C channel C and PECI used at the same time. */
+#undef CONFIG_IT83XX_SMCLK2_ON_GPC7
+
+/* Use SSPI Chip Enable 1. */
+#undef CONFIG_IT83XX_SPI_USE_CS1
+
 /*****************************************************************************/
 /* Keyboard config */
 
@@ -955,9 +967,6 @@
 /* Enable extra debugging output from keyboard modules */
 #undef CONFIG_KEYBOARD_DEBUG
 
-/* Enable Wake-up control interrupt from KSI */
-#undef CONFIG_KEYBOARD_KSI_WUC_INT
-
 /* The board uses a negative edge-triggered GPIO for keyboard interrupts. */
 #undef CONFIG_KEYBOARD_IRQ_GPIO
 
@@ -1287,9 +1296,6 @@
 /* SPI module port. */
 #undef CONFIG_SPI_PORT
 
-/* Use SSPI Chip Enable 1. */
-#undef CONFIG_SPI_USE_CS1
-
 /* Support testing SPI slave controller driver. */
 #undef CONFIG_SPS_TEST