i2c: Add Zhaoxin I2C driver

zhaoxin inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I6J3EV
CVE: NA

--------------------------------------------

Zhaoxin I2C Linux driver support all bidirectional bus protocols speed
specified in the I2C Specification 7.0. The speed mode listed in the
followed table.

|   Speed Name    |           Description                |
| Standard-mode   | Bit rate up to 100 kbit/s            |
| Fast-mode       | Bit rate up to 400 kbit/s.(default)  |
| Fast-mode Plus  | Bit rate up to 1 Mbit/s              |
| High-speed mode | Bit rate up to 3.4 Mbit/s.           |
Signed-off-by: Nleoliu-oc <leoliu-oc@zhaoxin.com>

drivers/i2c/busses/Kconfig

@@ -297,6 +297,18 @@ config I2C_VIAPRO
 	  This driver can also be built as a module.  If so, the module
 	  will be called i2c-viapro.
 
+config I2C_ZHAOXIN
+	tristate "Zhaoxin I2C controller driver"
+	depends on PCI && ACPI
+	select I2C_ALGOBIT
+	default m
+	help
+	  If you say yes to this option, support will be included for the
+	  Zhaoxin I2C interface
+
+	  This driver can also be built as a module.  If so, the module
+	  will be called i2c-zhaoxin.
+
 if ACPI
 
 comment "ACPI drivers"

drivers/i2c/busses/Makefile

@@ -25,6 +25,7 @@ obj-$(CONFIG_I2C_SIS630)	+= i2c-sis630.o
 obj-$(CONFIG_I2C_SIS96X)	+= i2c-sis96x.o
 obj-$(CONFIG_I2C_VIA)		+= i2c-via.o
 obj-$(CONFIG_I2C_VIAPRO)	+= i2c-viapro.o
+obj-$(CONFIG_I2C_ZHAOXIN)	+= i2c-zhaoxin.o
 
 # Mac SMBus host controller drivers
 obj-$(CONFIG_I2C_HYDRA)		+= i2c-hydra.o

drivers/i2c/busses/i2c-zhaoxin.c

+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * i2c-zhaoxin-i2c.c - Zhaoxin I2C controller driver
+ *
+ * Copyright(c) 2021 Shanghai Zhaoxin Corporation. All rights reserved.
+ *
+ */
+
+#define DRIVER_VERSION "1.3.0"
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/acpi.h>
+#include <linux/interrupt.h>
+#include <linux/version.h>
+#include <linux/platform_device.h>
+#include <linux/pci.h>
+
+#define ZX_I2C_NAME	"Zhaoxin-I2C"
+
+/*
+ * registers
+ */
+/* I2C MMIO Address Constants */
+#define IICCR_L                  0x00
+#define   MST_RST          BIT(7)
+#define   MST_RST_PATCH    BIT(6)
+#define   CPU_RDY          BIT(3)
+#define   TX_END           BIT(2)
+#define   RX_ACK           BIT(1)
+#define IICCR_H                  0x01
+#define   FIFO_EN          BIT(6)
+#define IICSLVADDR               0x02
+#define IICTCR                   0x03
+#define   FAST_SEL         BIT(7)
+#define   MASTER_RECV      BIT(6)
+#define   HS_SEL           BIT(5)
+#define IICSR                    0x04
+#define   SDA_I            BIT(3)
+#define   SCL_I            BIT(2)
+#define   READY            BIT(1)
+#define   RCV_NACK         BIT(0)
+#define IICISR                   0x06
+#define   IRQ_STS_BYTENACK BIT(5)
+#define   IRQ_STS_FIFONACK BIT(4)
+#define   IRQ_STS_FIFOEND  BIT(3)
+#define   IRQ_SCL_TIMEOUT  BIT(2)
+#define   IRQ_STS_BYTEEND  BIT(1)
+#define   IRQ_STS_ADDRNACK BIT(0)
+#define   IRQ_STS_MASK   (IRQ_STS_FIFOEND | IRQ_SCL_TIMEOUT | \
+			IRQ_STS_BYTEEND | IRQ_STS_ADDRNACK)
+#define IICIMR                   0x08
+#define   IRQ_EN_FIFOEND   BIT(3)
+#define   IRQ_EN_TIMEOUT   BIT(2)
+#define   IRQ_EN_BYTEEND   BIT(1)
+#define   IRQ_EN_ADDRNACK  BIT(0)
+#define IICDATA2IIC              0x0A
+#define IICDATA2CPU              0x0B
+#define IICTR_FSTP               0x0C
+#define IICTR_SCLTP              0x0D
+#define IICMCR                   0x0E
+#define   DYCLK_EN         BIT(0)
+#define IIC_MST_CODE             0x0F
+#define IICCS                    0x10
+#define   CLKSEL_50M       BIT(0)
+#define IICREV                   0x11
+#define IICHCR                   0x12
+#define   FIFO_RST         (BIT(1) | BIT(0))
+#define IICHTDR                  0x13
+#define IICHRDR                  0x14
+#define IICHTLR                  0x15
+#define IICHRLR                  0x16
+#define IICHWCNTR                0x18
+#define IICHRCNTR                0x19
+
+enum {
+	STANDARD_MODE_50M = 1,
+	STANDARD_MODE_27M,
+	FAST_MODE_50M,
+	FAST_MODE_27M,
+	FAST_PLUSE_MODE_50M,
+	FAST_PLUSE_MODE_27M,
+	HIGH_SPEED_MODE,
+	SPEED_MODE_CNT = HIGH_SPEED_MODE
+};
+
+#define FIFO_SIZE	32
+#define RETRY_TIME	3
+
+struct zxi2c {
+	/* controller resources information */
+	struct device    *dev;
+	struct pci_dev   *pci;
+	struct i2c_adapter adap;
+	void __iomem *regs;
+	u8 irq;
+	const char *bus_uid;
+	u8 hrv;		/* Hardware Revision */
+	u8 speed_mode;
+	unsigned long speed;
+	u8 fstp;	/* freq control */
+
+	/* process control information */
+	u8 event;
+	u16 timeout;
+	u16 byte_left;
+	wait_queue_head_t waitq;
+	u8 retry;
+	bool busy;
+
+	/* current msg information */
+	u8 addr;
+	u16 len;
+	bool is_read;
+	bool is_last_msg;
+	bool dynamic;
+};
+
+#define set_byte(r, d)           iowrite8(d, r+IICDATA2IIC)
+#define get_byte(r)              ioread8(r+IICDATA2CPU)
+#define is_ready(r)              (ioread8(r+IICSR)&READY)
+#define is_nack(r)               (ioread8(r+IICSR)&RCV_NACK)
+#define get_irq_status(r)        ioread8(r+IICISR)
+#define get_reversion(r)         ioread8(r+IICREV)
+#define clear_irq_status(r)      iowrite8(IRQ_STS_MASK, r+IICISR)
+#define set_fifo_byte(r, d)      iowrite8(d, r+IICHTDR)
+#define get_fifo_byte(r)         ioread8(r+IICHRDR)
+#define set_fifo_wr_len(r, d)    iowrite8(d, r+IICHTLR)
+#define set_fifo_rd_len(r, d)    iowrite8(d, r+IICHRLR)
+#define get_fifo_wr_cnt(r)       ioread8(r+IICHWCNTR)
+#define get_fifo_rd_cnt(r)       ioread8(r+IICHRCNTR)
+#define master_regs_reset(r)     iowrite8(MST_RST|0x41, r+IICCR_L)
+#define set_dynamic_clock(r, d)  iowrite8(d, r+IICMCR)
+#define get_dynamic_clock(r)     (ioread8(r+IICMCR) & DYCLK_EN)
+#define stop_write_byte(r)       iowrite8(TX_END|0x41, r+IICCR_L)
+#define get_fstp_value(r)         ioread8(r+IICTR_FSTP)
+
+static inline void zxi2c_prepare_next_read(void __iomem *regs, u16 left)
+{
+	u8 tmp = ioread8(regs + IICCR_L);
+
+	if (left > 1)
+		tmp &= ~RX_ACK;
+	else
+		tmp |= RX_ACK;
+
+	iowrite8(tmp, regs + IICCR_L);
+}
+
+static inline void zxi2c_enable_irq(void __iomem *regs, u8 type, int mode)
+{
+	if (mode == true)
+		iowrite8(IRQ_EN_ADDRNACK | type,
+			regs + IICIMR);
+	else
+		iowrite8(0, regs + IICIMR);
+}
+
+static inline void zxi2c_continue(struct zxi2c *i2c)
+{
+	u8 tmp;
+
+	i2c->event = 0;
+	tmp = ioread8(i2c->regs + IICCR_L);
+	iowrite8(tmp |= CPU_RDY, i2c->regs + IICCR_L);
+}
+
+static void zxi2c_enable_fifo(void __iomem *regs, int mode)
+{
+	if (mode == true)
+		iowrite8(FIFO_EN, regs + IICCR_H);
+	else
+		iowrite8(0, regs + IICCR_H);
+}
+
+static void zxi2c_reset_fifo(void __iomem *regs)
+{
+	u8 tmp;
+	u8 count;
+
+	tmp = ioread8(regs + IICHCR);
+	iowrite8(tmp | FIFO_RST, regs + IICHCR);
+	for (count = 0; count < 50; count++)
+		if (!(ioread8(regs + IICHCR) & FIFO_RST))
+			break;
+	if (count >= 50)
+		pr_err("%s failed\n", __func__);
+}
+
+static void zxi2c_set_wr(void __iomem *regs, bool is_read)
+{
+	u8 tmp;
+
+	tmp = ioread8(regs + IICTCR);
+	if (is_read)
+		tmp |= MASTER_RECV;
+	else
+		tmp &= ~MASTER_RECV;
+	iowrite8(tmp, regs + IICTCR);
+}
+
+static void zxi2c_start(struct zxi2c *i2c)
+{
+	i2c->event = 0;
+	iowrite8(i2c->addr & 0x7f, i2c->regs + IICSLVADDR);
+}
+
+static const u8 speed_params_table[SPEED_MODE_CNT][5] = {
+	/* speed_mode, IICTCR, IICTR_FSTP, IICCS, IICTR_SCLTP */
+	{ STANDARD_MODE_27M, 0, 0x83, 0, 0x80 },
+	{ FAST_MODE_27M, FAST_SEL, 0x1e, 0, 0x80 },
+	{ FAST_PLUSE_MODE_27M, FAST_SEL, 10, 0, 0x80 },
+	{ STANDARD_MODE_50M, 0, 0xF3, CLKSEL_50M, 0xff },
+	{ FAST_MODE_50M, FAST_SEL, 0x38, CLKSEL_50M, 0xff },
+	{ FAST_PLUSE_MODE_50M, FAST_SEL, 19, CLKSEL_50M, 0xff },
+	{ HIGH_SPEED_MODE, HS_SEL, 0x37, CLKSEL_50M, 0xff }
+
+};
+
+static void zxi2c_set_bus_speed(struct zxi2c *i2c)
+{
+	u8 i;
+	const u8 *params = NULL;
+
+	for (i = 0; i < SPEED_MODE_CNT; i++) {
+		if (speed_params_table[i][0] == i2c->speed_mode) {
+			params = speed_params_table[i];
+			break;
+		}
+	}
+	iowrite8(params[1], i2c->regs + IICTCR);
+	if (abs(i2c->fstp - params[2]) > 0x10) {
+		/* if BIOS setting value far from golden value,
+		 * use golden value and warn user */
+		dev_warn(i2c->dev,
+			"speed:%ld, fstp:0x%x, golden:0x%x\n",
+			i2c->speed, i2c->fstp, params[2]);
+		iowrite8(params[2], i2c->regs + IICTR_FSTP);
+	} else
+		iowrite8(i2c->fstp, i2c->regs + IICTR_FSTP);
+	iowrite8(params[3], i2c->regs + IICCS);
+	iowrite8(params[4], i2c->regs + IICTR_SCLTP);
+
+	/* for Hs-mode, use 0000 1000 as master code */
+	if (i2c->speed_mode == HIGH_SPEED_MODE)
+		iowrite8(0x08, i2c->regs + IIC_MST_CODE);
+}
+
+static void zxi2c_module_reset(struct zxi2c *i2c)
+{
+	unsigned long uid;
+	u8 tmp;
+	u8 bit;
+
+	bit = kstrtoul(i2c->bus_uid, 10, &uid) ? 0 : (1 << (4 + uid));
+
+	pci_read_config_byte(i2c->pci, 0x4F, &tmp);
+	usleep_range(3000, 5000);
+	pci_write_config_byte(i2c->pci, 0x4F, tmp & ~bit);
+	usleep_range(3000, 5000);
+	pci_write_config_byte(i2c->pci, 0x4F, tmp | bit);
+	usleep_range(3000, 5000);
+
+	set_dynamic_clock(i2c->regs, i2c->dynamic);
+}
+
+static irqreturn_t zxi2c_irq_handle(int irq, void *dev_id)
+{
+	struct zxi2c *i2c = (struct zxi2c *)dev_id;
+	void __iomem *regs = i2c->regs;
+	u8 status = get_irq_status(regs);
+
+	if ((status & IRQ_STS_MASK) == 0)
+		return IRQ_NONE;
+
+	if (status & IRQ_SCL_TIMEOUT)
+		dev_warn(i2c->dev, "timeout(HW), ID: 0x%X\n", i2c->addr);
+
+	if (status & IRQ_STS_ADDRNACK)
+		dev_err(i2c->dev, "addr NACK, ID: 0x%X\n", i2c->addr);
+	else if (status & IRQ_STS_BYTEEND) {
+		i2c->byte_left--;
+		if (!i2c->is_read) {
+			if (is_nack(regs)) {
+				status = IRQ_STS_BYTENACK;
+				i2c->byte_left++;
+				dev_err(i2c->dev, "data NACK, ID: 0x%X\n", i2c->addr);
+			} else if (i2c->byte_left == 0 && i2c->is_last_msg)
+				stop_write_byte(regs);
+		}
+	}
+
+	i2c->event = status;
+	clear_irq_status(regs);
+	wake_up(&i2c->waitq);
+
+	return IRQ_HANDLED;
+}
+
+static int zxi2c_wait_event(struct zxi2c *i2c, u8 event)
+{
+	int timeout;
+
+	timeout = wait_event_interruptible_timeout(i2c->waitq, i2c->event != 0,
+					msecs_to_jiffies(i2c->timeout));
+
+	if (timeout == 0) {
+		dev_err(i2c->dev, "timeout(SW), ID: 0x%X\n", i2c->addr);
+		/* Clock streching timeout, do recovery */
+		if (!is_nack(i2c->regs))
+			dev_err(i2c->dev, "device hang? pls reset, ID: 0x%X\n", i2c->addr);
+
+		master_regs_reset(i2c->regs);
+		zxi2c_set_bus_speed(i2c);
+		return -ENODEV;
+	} else if ((i2c->event & event) == 0) {
+		/* device NACK and so on, already print in interrupt */
+		return -ENODEV;
+	}
+	return 0;
+}
+
+static int zxi2c_byte_xfer(struct zxi2c *i2c, struct i2c_msg *msgs, int num)
+{
+	u16 i, finished;
+	int error;
+	u8 index, ret = 0;
+	struct i2c_msg *msg;
+	void __iomem *regs = i2c->regs;
+
+	clear_irq_status(regs);
+	zxi2c_enable_fifo(regs, false);
+	zxi2c_enable_irq(regs, IRQ_EN_BYTEEND, true);
+
+	for (index = 0; index < num; index++) {
+		msg = msgs + index;
+
+		i2c->addr = msg->addr;
+		i2c->is_read = !!(msg->flags & I2C_M_RD);
+		i2c->byte_left = i2c->len = msg->len;
+
+		zxi2c_set_wr(regs, i2c->is_read);
+		if (i2c->is_read) {
+			zxi2c_prepare_next_read(regs, i2c->byte_left);
+			zxi2c_start(i2c);
+			/* create restart for non-first msg*/
+			if (index)
+				zxi2c_continue(i2c);
+
+			for (i = 1; i <= msg->len; i++) {
+				error = zxi2c_wait_event(i2c, IRQ_STS_BYTEEND);
+				if (error)
+					break;
+
+				msg->buf[i - 1] = get_byte(regs);
+				if (i2c->byte_left == 0)
+					break;
+
+				zxi2c_prepare_next_read(regs, i2c->byte_left);
+				zxi2c_continue(i2c);
+			}
+		} else {
+			set_byte(regs, msg->buf[0]);
+			/* mark whether this is the last msg */
+			i2c->is_last_msg = index == !!(num - 1);
+			zxi2c_start(i2c);
+			/* create restart for non-first msg */
+			if (index)
+				zxi2c_continue(i2c);
+
+			for (i = 1; i <= msg->len; i++) {
+				error = zxi2c_wait_event(i2c, IRQ_STS_BYTEEND);
+				if (error)
+					break;
+
+				if (i2c->byte_left == 0)
+					break;
+				set_byte(regs, msg->buf[i]);
+				zxi2c_continue(i2c);
+			}
+		}
+
+		if (error) {
+			finished = msg->len - i2c->byte_left;
+
+			/* check if NACK during transmitting */
+			if (finished)
+				dev_err(i2c->dev,
+					"%s: %s finished %d bytes: %*ph\n",
+					__func__, i2c->is_read ? "read" : "write",
+					finished, finished, msg->buf);
+			return error;
+		}
+		ret++;
+	}
+
+	zxi2c_enable_irq(regs, IRQ_EN_BYTEEND, false);
+	return ret;
+}
+
+static int zxi2c_fifo_xfer(struct zxi2c *i2c, struct i2c_msg *msgs)
+{
+	void __iomem *regs = i2c->regs;
+	struct i2c_msg *msg = msgs;
+	int i;
+	u8 finished;
+
+	i2c->addr = msg->addr;
+	i2c->is_read = !!(msg->flags & I2C_M_RD);
+	i2c->len = msg->len;
+
+	zxi2c_reset_fifo(regs);
+	zxi2c_enable_fifo(regs, true);
+
+	clear_irq_status(regs);
+	zxi2c_enable_irq(regs, IRQ_EN_FIFOEND, true);
+
+	zxi2c_set_wr(regs, i2c->is_read);
+	if (i2c->is_read)
+		set_fifo_rd_len(regs, msg->len - 1);
+	else {
+		set_fifo_wr_len(regs, msg->len - 1);
+		for (i = 0; i < msg->len; i++)
+			set_fifo_byte(regs, msg->buf[i]);
+	}
+
+	zxi2c_start(i2c);
+	if (zxi2c_wait_event(i2c, IRQ_STS_FIFOEND))
+		return -ENODEV;
+
+	if (i2c->is_read) {
+		finished = get_fifo_rd_cnt(regs);
+		for (i = 0; i < finished; i++)
+			msg->buf[i] = get_fifo_byte(regs);
+	} else
+		finished = get_fifo_wr_cnt(regs);
+
+	/* check if NACK during transmitting */
+	if (finished != msg->len) {
+		if (finished)
+			dev_err(i2c->dev,
+				"%s: %s only finished %d/%d bytes: %*ph\n",
+				__func__, i2c->is_read ? "read" : "write",
+				finished, msg->len, finished, msg->buf);
+		return -EAGAIN;
+	}
+
+	zxi2c_enable_irq(regs, IRQ_EN_FIFOEND, false);
+	return 1;
+}
+
+static int zxi2c_master_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+	struct zxi2c *i2c;
+	int ret;
+
+	i2c = (struct zxi2c *)i2c_get_adapdata(adap);
+	if (!is_ready(i2c->regs)) {
+		if (i2c->busy == false) {
+			zxi2c_module_reset(i2c);
+			zxi2c_set_bus_speed(i2c);
+			dev_dbg(i2c->dev, "not ready, reset and retry\n");
+		}
+		if (i2c->retry >= RETRY_TIME) {
+			dev_err(i2c->dev, "retried %d times, dropped\n", i2c->retry);
+			i2c->retry = 0;
+		} else
+			i2c->retry++;
+		return -EAGAIN;
+	}
+	i2c->retry = 0;
+	i2c->busy = true;
+	i2c->timeout = 1000;
+
+	/* Freedom mode */
+	if (num == 1 && msgs->len <= FIFO_SIZE && msgs->len >= 3)
+		ret = zxi2c_fifo_xfer(i2c, msgs);
+	else
+		ret = zxi2c_byte_xfer(i2c, msgs, num);
+
+	i2c->busy = false;
+	return ret;
+}
+
+static u32 zxi2c_func(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
+}
+
+static const struct i2c_algorithm zxi2c_algorithm = {
+	.master_xfer	= zxi2c_master_xfer,
+	.functionality	= zxi2c_func,
+};
+
+static const struct i2c_adapter_quirks zxi2c_quirks = {
+	.flags = I2C_AQ_NO_ZERO_LEN | I2C_AQ_COMB_WRITE_THEN_READ,
+};
+
+static void zxi2c_get_speed_mode(struct zxi2c *i2c)
+{
+	u32 speed = 400000;
+
+	speed = i2c_acpi_find_bus_speed(i2c->dev);
+	if (speed >= 3400000)
+		i2c->speed_mode = HIGH_SPEED_MODE;
+	else if (speed >= 1000000)
+		i2c->speed_mode = FAST_PLUSE_MODE_50M;
+	else if (speed >= 400000)
+		i2c->speed_mode = FAST_MODE_50M;
+	else if (speed >= 100000)
+		i2c->speed_mode = STANDARD_MODE_50M;
+	else
+		i2c->speed_mode = FAST_MODE_50M;
+	i2c->speed = speed;
+}
+
+static int zxi2c_parse_resources(struct zxi2c *i2c)
+{
+	struct resource *res;
+	struct platform_device *pdev = to_platform_device(i2c->dev);
+	struct acpi_device *adev = ACPI_COMPANION(&pdev->dev);
+
+	/* get IO resource */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (IS_ERR(res)) {
+		dev_err(&pdev->dev, "IORESOURCE_MEM failed\n");
+		return -ENODEV;
+	}
+	i2c->regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(i2c->regs)) {
+		dev_err(&pdev->dev, "devm ioremap failed\n");
+		return -ENOMEM;
+	}
+
+	/* get irq */
+	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+	if (IS_ERR(res)) {
+		dev_err(&pdev->dev, "get IORESOURCE_IRQ failed\n");
+		return -ENODEV;
+	}
+	i2c->irq = res->start;
+
+	/* get _UID */
+	i2c->bus_uid = adev->pnp.unique_id;
+	if (!i2c->bus_uid) {
+		dev_err(&pdev->dev, "missing/incorrect UID/bus id!\n");
+		return -ENODEV;
+	}
+
+	/* get speed */
+	zxi2c_get_speed_mode(i2c);
+
+	return 0;
+}
+
+static int zxi2c_probe(struct platform_device *pdev)
+{
+	int error;
+	struct zxi2c *i2c;
+	struct pci_dev *pci;
+	struct device *dev;
+
+	dev = pdev->dev.parent;
+	if (dev && dev_is_pci(dev)) {
+		pci = to_pci_dev(dev);
+		if (pci->vendor != 0x1d17 || pci->device != 0x1001)
+			return -ENODEV;
+	} else
+		return -ENODEV;
+
+	i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
+	if (IS_ERR(i2c)) {
+		dev_err(&pdev->dev, "devm_kzalloc FAILED\n");
+		return -ENOMEM;
+	}
+
+	i2c->dev = &pdev->dev;
+	error = zxi2c_parse_resources(i2c);
+	if (error)
+		return error;
+
+	i2c->pci = pci;
+	i2c->hrv = get_reversion(i2c->regs);
+
+	platform_set_drvdata(pdev, (void *)i2c);
+
+	if (devm_request_irq(&pdev->dev, i2c->irq, zxi2c_irq_handle, IRQF_SHARED,
+			pdev->name, i2c)) {
+		dev_err(i2c->dev, "i2c IRQ%d allocate failed.\n", i2c->irq);
+		return -ENODEV;
+	}
+
+	init_waitqueue_head(&i2c->waitq);
+	i2c->retry = 0;
+	i2c->busy = false;
+
+	i2c->adap.owner = THIS_MODULE;
+	i2c->adap.algo = &zxi2c_algorithm;
+	i2c->adap.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
+	i2c->adap.retries = RETRY_TIME + 1;
+	i2c->adap.quirks = &zxi2c_quirks;
+
+	i2c->adap.owner = THIS_MODULE;
+	i2c->adap.dev.parent = &pdev->dev;
+	ACPI_COMPANION_SET(&i2c->adap.dev, ACPI_COMPANION(&pdev->dev));
+	snprintf(i2c->adap.name, sizeof(i2c->adap.name), "%s.%s", ZX_I2C_NAME, i2c->bus_uid);
+	i2c_set_adapdata(&i2c->adap, i2c);
+
+	i2c->dynamic = get_dynamic_clock(i2c->regs);
+	set_dynamic_clock(i2c->regs, i2c->dynamic);
+	i2c->fstp = get_fstp_value(i2c->regs);
+	zxi2c_set_bus_speed(i2c);
+
+	error = i2c_add_adapter(&i2c->adap);
+	if (unlikely(error)) {
+		dev_err(i2c->dev, "failed to register i2c, err: %d\n", error);
+		return error;
+	}
+
+	dev_info(i2c->dev, "Adapter %s registered at /dev/i2c-%d\n", i2c->adap.name, i2c->adap.nr);
+
+	return 0;
+}
+
+static int zxi2c_remove(struct platform_device *pdev)
+{
+	struct zxi2c *i2c = platform_get_drvdata(pdev);
+
+	zxi2c_module_reset(i2c);
+	master_regs_reset(i2c->regs);
+
+	devm_free_irq(&pdev->dev, i2c->irq, i2c);
+
+	i2c_del_adapter(&i2c->adap);
+
+	platform_set_drvdata(pdev, NULL);
+	devm_kfree(&pdev->dev, i2c);
+
+	dev_info(&pdev->dev, "i2c adapter unregistered.\n");
+
+	return 0;
+}
+
+static int zxi2c_suspend(struct device *dev)
+{
+	return 0;
+}
+
+static int zxi2c_resume(struct device *dev)
+{
+	struct zxi2c *i2c = dev_get_drvdata(dev);
+
+	zxi2c_module_reset(i2c);
+	zxi2c_set_bus_speed(i2c);
+
+	return 0;
+}
+
+const struct dev_pm_ops zxi2c_pm = {
+	SET_SYSTEM_SLEEP_PM_OPS(zxi2c_suspend, zxi2c_resume)
+};
+
+static const struct acpi_device_id zxi2c_acpi_match[] = {
+	{"IIC1D17", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(acpi, zxi2c_acpi_match);
+
+static struct platform_driver zxi2c_driver = {
+	.probe   = zxi2c_probe,
+	.remove  = zxi2c_remove,
+	.driver  = {
+		.name = ZX_I2C_NAME,
+		.owner = THIS_MODULE,
+		.acpi_match_table = ACPI_PTR(zxi2c_acpi_match),
+		.pm = &zxi2c_pm,
+	},
+};
+
+module_platform_driver(zxi2c_driver);
+
+MODULE_AUTHOR("HansHu@zhaoxin.com");
+MODULE_DESCRIPTION("Shanghai Zhaoxin IIC driver");
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL v2");