[PATCH] input: add synaptics_i2c driver

[Mike Rapoport <mike@compulab.co.il>]

From: Igor Grinberg <grinberg@compulab.co.il>

This patch adds support for Synaptics i2c touchpad controller found on
eXeda machine.

Signed-off-by: Igor Grinberg <grinberg@compulab.co.il>
Signed-off-by: Mike Rapoport <mike@compulab.co.il>
---
 drivers/input/mouse/Kconfig         |    9 +
 drivers/input/mouse/Makefile        |    1 +
 drivers/input/mouse/synaptics_i2c.c |  775 +++++++++++++++++++++++++++++++++++
 3 files changed, 785 insertions(+), 0 deletions(-)
 create mode 100644 drivers/input/mouse/synaptics_i2c.c

diff --git a/drivers/input/mouse/Kconfig b/drivers/input/mouse/Kconfig
index c66cc3d..89192f5 100644
--- a/drivers/input/mouse/Kconfig
+++ b/drivers/input/mouse/Kconfig
@@ -303,4 +303,13 @@ config MOUSE_MAPLE
 	  To compile this driver as a module choose M here: the module will be
 	  called maplemouse.
 
+config MOUSE_SYNAPTICS_I2C
+	tristate "Synaptics I2C Touchpad support"
+	depends on I2C
+	help
+	  Say y here if you want to use a Synaptics I2C Touchpad.
+
+	  To compile this driver as a module, choose M here: the
+	  module will be called synaptics_i2c.
+
 endif
diff --git a/drivers/input/mouse/Makefile b/drivers/input/mouse/Makefile
index 4721894..010f265 100644
--- a/drivers/input/mouse/Makefile
+++ b/drivers/input/mouse/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_MOUSE_PS2)			+= psmouse.o
 obj-$(CONFIG_MOUSE_PXA930_TRKBALL)	+= pxa930_trkball.o
 obj-$(CONFIG_MOUSE_RISCPC)		+= rpcmouse.o
 obj-$(CONFIG_MOUSE_SERIAL)		+= sermouse.o
+obj-$(CONFIG_MOUSE_SYNAPTICS_I2C)	+= synaptics_i2c.o
 obj-$(CONFIG_MOUSE_VSXXXAA)		+= vsxxxaa.o
 
 psmouse-objs := psmouse-base.o synaptics.o
diff --git a/drivers/input/mouse/synaptics_i2c.c b/drivers/input/mouse/synaptics_i2c.c
new file mode 100644
index 0000000..de2c363
--- /dev/null
+++ b/drivers/input/mouse/synaptics_i2c.c
@@ -0,0 +1,775 @@
+/*
+ * Synaptics touchpad with I2C interface
+ *
+ * Copyright (C) 2009 Compulab, Ltd.
+ * Mike Rapoport <mike@compulab.co.il>
+ * Igor Grinberg <grinberg@compulab.co.il>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive for
+ * more details.
+ */
+
+#include <linux/module.h>
+#include <linux/ctype.h>
+#include <linux/uaccess.h>
+#include <linux/i2c.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/delay.h>
+#include <linux/kthread.h>
+#include <linux/completion.h>
+#include <linux/freezer.h>
+
+#define DRIVER_NAME		"synaptics_i2c"
+/* According to RMI manual, maximum product id is 15 characters */
+#define PRODUCT_ID_LENGTH	15
+#define REGISTER_LENGTH		8
+
+/* According to RMI manual, after soft reset, we should */
+/* wait for 1 ms before the device becomes operational */
+#define SOFT_RESET_DELAY_MS	3
+/* and after hard reset, we should wait for max 500ms */
+#define HARD_RESET_DELAY_MS	500
+
+/* Define Registers by SMBus address */
+#define PAGE_SEL_REG		0xff
+#define DEVICE_STATUS_REG	0x09
+
+/* Define Registers by RMI address */
+#define DEV_CONTROL_REG		0x0000
+#define INTERRUPT_EN_REG	0x0001
+#define ERR_STAT_REG		0x0002
+#define INT_REQ_STAT_REG	0x0003
+#define DEV_COMMAND_REG		0x0004
+
+#define RMI_PROT_VER_REG	0x0200
+#define MANUFACT_ID_REG		0x0201
+#define PHYS_INT_VER_REG	0x0202
+#define PROD_PROPERTY_REG	0x0203
+#define INFO_QUERY_REG0		0x0204
+#define INFO_QUERY_REG1		(INFO_QUERY_REG0 + 1)
+#define INFO_QUERY_REG2		(INFO_QUERY_REG0 + 2)
+#define INFO_QUERY_REG3		(INFO_QUERY_REG0 + 3)
+
+#define PRODUCT_ID_REG0		0x0210
+#define PRODUCT_ID_REG1		(PRODUCT_ID_REG0 + 1)
+#define PRODUCT_ID_REG2		(PRODUCT_ID_REG0 + 2)
+#define PRODUCT_ID_REG3		(PRODUCT_ID_REG0 + 3)
+#define PRODUCT_ID_REG4		(PRODUCT_ID_REG0 + 4)
+#define PRODUCT_ID_REG5		(PRODUCT_ID_REG0 + 5)
+#define PRODUCT_ID_REG6		(PRODUCT_ID_REG0 + 6)
+#define PRODUCT_ID_REG7		(PRODUCT_ID_REG0 + 7)
+#define PRODUCT_ID_REG8		(PRODUCT_ID_REG0 + 8)
+#define PRODUCT_ID_REG9		(PRODUCT_ID_REG0 + 9)
+#define PRODUCT_ID_REG10	(PRODUCT_ID_REG0 + 10)
+#define PRODUCT_ID_REG11	(PRODUCT_ID_REG0 + 11)
+#define PRODUCT_ID_REG12	(PRODUCT_ID_REG0 + 12)
+#define PRODUCT_ID_REG13	(PRODUCT_ID_REG0 + 13)
+#define PRODUCT_ID_REG14	(PRODUCT_ID_REG0 + 14)
+#define PRODUCT_ID_REG15	(PRODUCT_ID_REG0 + 15)
+
+#define DATA_REG0		0x0400
+#define ABS_PRESSURE_REG	0x0401
+#define ABS_MSB_X_REG		0x0402
+#define ABS_LSB_X_REG		(ABS_MSB_X_REG + 1)
+#define ABS_MSB_Y_REG		0x0404
+#define ABS_LSB_Y_REG		(ABS_MSB_Y_REG + 1)
+#define REL_X_REG		0x0406
+#define REL_Y_REG		0x0407
+
+#define DEV_QUERY_REG0		0x1000
+#define DEV_QUERY_REG1		(DEV_QUERY_REG0 + 1)
+#define DEV_QUERY_REG2		(DEV_QUERY_REG0 + 2)
+#define DEV_QUERY_REG3		(DEV_QUERY_REG0 + 3)
+#define DEV_QUERY_REG4		(DEV_QUERY_REG0 + 4)
+#define DEV_QUERY_REG5		(DEV_QUERY_REG0 + 5)
+#define DEV_QUERY_REG6		(DEV_QUERY_REG0 + 6)
+#define DEV_QUERY_REG7		(DEV_QUERY_REG0 + 7)
+#define DEV_QUERY_REG8		(DEV_QUERY_REG0 + 8)
+
+#define GENERAL_2D_CONTROL_REG	0x1041
+#define SENSOR_SENSITIVITY_REG	0x1044
+#define SENS_MAX_POS_MSB_REG	0x1046
+#define SENS_MAX_POS_LSB_REG	(SENS_MAX_POS_UPPER_REG + 1)
+
+/* Define Register bits */
+/* Device Control Register Bits */
+#define REPORT_RATE_1ST_BIT	6
+
+/* Interrupt Enable Register Bits (INTERRUPT_EN_REG) */
+#define F10_ABS_INT_ENA		0
+#define F10_REL_INT_ENA		1
+#define F20_INT_ENA		2
+
+/* Interrupt Request Register Bits (INT_REQ_STAT_REG | DEVICE_STATUS_REG) */
+#define F10_ABS_INT_REQ		0
+#define F10_REL_INT_REQ		1
+#define F20_INT_REQ		2
+/* Device Status Register Bits (DEVICE_STATUS_REG) */
+#define STAT_CONFIGURED		6
+#define STAT_ERROR		7
+
+/* Device Command Register Bits (DEV_COMMAND_REG) */
+#define RESET_COMMAND		0x01
+#define REZERO_COMMAND		0x02
+
+/* Data Register 0 Bits (DATA_REG0) */
+#define GESTURE			3
+
+/* Device Query Registers Bits */
+/* DEV_QUERY_REG3 */
+#define HAS_PALM_DETECT		1
+#define HAS_MULTI_FING		2
+#define HAS_SCROLLER		4
+#define HAS_2D_SCROLL		5
+
+/* General 2D Control Register Bits (GENERAL_2D_CONTROL_REG) */
+#define NO_DECELERATION		1
+#define REDUCE_REPORTING	3
+#define NO_FILTER		5
+
+#define GET_BIT(bit, val)	(((val) >> (bit)) & 0x01)
+
+/* Define Function Masks */
+/* Device Control Register Masks (DEV_CONTROL_REG) */
+#define REPORT_RATE_MSK		0xc0
+#define SLEEP_MODE_MSK		0x07
+
+/* Interrupt Register Mask */
+/* (INT_REQ_STAT_REG | DEVICE_STATUS_REG | INTERRUPT_EN_REG) */
+#define INT_ENA_REQ_MSK		0x07
+#define INT_ENA_ABS_MSK		0x01
+#define INT_ENA_REL_MSK		0x02
+#define INT_ENA_F20_MSK		0x04
+
+/* Device Status Register Masks (DEVICE_STATUS_REG) */
+#define CONFIGURED_MSK		0x40
+#define ERROR_MSK		0x80
+
+/* Data Register 0 Masks */
+#define FINGER_WIDTH_MSK	0xf0
+#define GESTURE_MSK		0x08
+#define SENSOR_STATUS_MSK	0x07
+
+/* MSB Position Register Masks */
+/* ABS_MSB_X_REG | ABS_MSB_Y_REG | SENS_MAX_POS_MSB_REG |  */
+/* DEV_QUERY_REG3 | DEV_QUERY_REG5 */
+#define MSB_POSITION_MSK	0x1f
+
+/* Device Query Registers Masks */
+/* DEV_QUERY_REG2 */
+#define NUM_EXTRA_POS_MSK	0x07
+
+/* When in IRQ mode read the device every THREAD_IRQ_SLEEP_SECS */
+#define THREAD_IRQ_SLEEP_SECS	2
+#define THREAD_IRQ_SLEEP_MSECS	(THREAD_IRQ_SLEEP_SECS * MSEC_PER_SEC)
+
+/* When in Polling mode and no data received for NO_DATA_THRES msecs*/
+/* reduce the polling rate to NO_DATA_SLEEP_MSECS */
+#define NO_DATA_THRES		(MSEC_PER_SEC)
+#define NO_DATA_SLEEP_MSECS	(MSEC_PER_SEC / 4)
+
+/* The Acceleration Factor:
+ * from 0.5 (1) to 4 (8) in dozes of 0.5
+ * the transformation is done in order to get 0.5 resolution.
+ * values above 8 will affect poor performance without proper smoothing.
+ */
+#define ACCEL_DIVIDER 10
+#define ACCEL_DOZE 2
+static int accel = 4;
+module_param(accel, int, 0644);
+MODULE_PARM_DESC(accel, "Set Acceleration parameter 1..8. Default = 4");
+
+/* Control touchpad's No Deceleration option */
+static int no_decel = 1;
+module_param(no_decel, bool, 0644);
+MODULE_PARM_DESC(no_decel, "No Deceleration. Default = 1 (on)");
+
+/* Control touchpad's Reduced Reporting option */
+static int reduce_report;
+module_param(reduce_report, bool, 0644);
+MODULE_PARM_DESC(reduce_report, "Reduced Reporting. Default = 0 (off)");
+
+/* Control touchpad's No Filter option */
+static int no_filter;
+module_param(no_filter, bool, 0644);
+MODULE_PARM_DESC(no_filter, "No Filter. Default = 0 (off)");
+
+/* According to Synaptics manual the Attention line is Active Low */
+/* and Open Drain, therefore should be connected to pulled up line */
+/* and the irq configuration should be set to Falling Edge Trigger */
+/* Control IRQ / Polling option */
+static int polling_req;
+module_param(polling_req, bool, 0444);
+MODULE_PARM_DESC(polling_req, "Request Polling. Default = 0 (use irq)");
+
+/* Control Polling Rate */
+static int scan_rate = 80;
+module_param(scan_rate, int, 0644);
+MODULE_PARM_DESC(scan_rate, "Polling rate in times/sec. Default = 80");
+
+/* Print Device Info */
+static int query;
+module_param(query, bool, 0444);
+MODULE_PARM_DESC(query, "Print Device Query. Default = 0");
+
+/* The main device structure */
+struct synaptics_i2c {
+	struct i2c_client	*client;
+	struct input_dev	*input;
+	struct task_struct	*thread;
+	struct completion	touch_completion;
+	struct completion	thread_completion;
+	int			thread_stop;
+	int			suspend_link;
+	int			users_count;
+	int			no_data_count;
+	int			no_decel_param;
+	int			reduce_report_param;
+	int			no_filter_param;
+	int			scan_rate_param;
+	int			accel_param;
+	int			accel;	/* Transformed acceleration */
+	int			scan_ms;
+};
+
+static inline void set_acceleration(struct synaptics_i2c *touch, int accel)
+{
+	int acc = (accel < 1) ? 1 : ((accel > 8) ? 8 : accel);
+	touch->accel = (acc * ACCEL_DIVIDER) / ACCEL_DOZE;
+	touch->accel_param = accel;
+}
+
+static inline void set_scan_rate(struct synaptics_i2c *touch, int scan_rate)
+{
+	touch->scan_ms = MSEC_PER_SEC / scan_rate;
+	touch->scan_rate_param = scan_rate;
+}
+
+static s32 synaptics_i2c_reg_get(struct i2c_client *client, u16 reg)
+{
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8);
+	if (ret)
+		return ret;
+
+	return 	i2c_smbus_read_byte_data(client, reg & 0xff);
+}
+
+static s32 synaptics_i2c_reg_set(struct i2c_client *client, u16 reg, u8 val)
+{
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8);
+	if (ret)
+		return ret;
+
+	return i2c_smbus_write_byte_data(client, reg & 0xff, val);
+}
+
+static s32 synaptics_i2c_word_get(struct i2c_client *client, u16 reg)
+{
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8);
+	if (ret)
+		return ret;
+
+	return i2c_smbus_read_word_data(client, reg & 0xff);
+}
+
+static s32 synaptics_i2c_block_read(struct i2c_client *client,
+				    u16 reg, u8 length, u8 *values)
+{
+	int ret;
+
+	ret = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8);
+	if (ret)
+		return ret;
+
+	return i2c_smbus_read_i2c_block_data(client, reg & 0xff,
+					     length, values);
+}
+
+static int synaptics_i2c_query(struct i2c_client *client)
+{
+	u8 data[7];
+	char id[PRODUCT_ID_LENGTH + 1];
+	int ret, retry_count, control, status, sens;
+
+	/* DEV_QUERY_REG0 is the Function Query area for 2D devices. */
+	/* We're only interested in entries DEV_QUERY_REG2 */
+	/* and following registers right now. */
+	for (retry_count = 0; retry_count < 3; retry_count++) {
+		ret = synaptics_i2c_block_read(client, DEV_QUERY_REG2,
+					       sizeof(data), data);
+		if (ret != sizeof(data))
+			continue;
+
+		dev_info(&client->dev, "Number of extra positions: %d\n",
+			  data[0] & NUM_EXTRA_POS_MSK);
+		dev_info(&client->dev, "Has 2D Scroll: %d\n",
+			  GET_BIT(HAS_2D_SCROLL, data[1]));
+		dev_info(&client->dev, "Has Scroller: %d\n",
+			  GET_BIT(HAS_SCROLLER, data[1]));
+		dev_info(&client->dev, "Has Multifing: %d\n",
+			  GET_BIT(HAS_MULTI_FING, data[1]));
+		dev_info(&client->dev, "Has Palm Det: %d\n",
+			  GET_BIT(HAS_PALM_DETECT, data[1]));
+		dev_info(&client->dev, "Sensor Max X: %d\n",
+			((data[2] & MSB_POSITION_MSK) << REGISTER_LENGTH)
+			| data[3]);
+		dev_info(&client->dev, "Sensor Max Y: %d\n",
+			((data[4] & MSB_POSITION_MSK) << REGISTER_LENGTH)
+			| data[5]);
+		dev_info(&client->dev, "Sensor Resolution: %d\n", data[6]);
+		break;
+	}
+	if (retry_count >= 5)
+		dev_warn(&client->dev,
+			  "Query command failed: block read failed\n");
+
+	control = synaptics_i2c_reg_get(client, DEV_CONTROL_REG);
+	dev_info(&client->dev, "Default Report Rate: 0x%x\n",
+		  (control & REPORT_RATE_MSK) >> REPORT_RATE_1ST_BIT);
+	dev_info(&client->dev, "Sleep Mode: 0x%x\n",
+		  control & SLEEP_MODE_MSK);
+
+	/* The Touchpad's manual doesn't document the RMI address of the */
+	/* Device Status Register and niether does RMI manual, */
+	/* so we use the SMBus address */
+	status = i2c_smbus_read_byte_data(client, DEVICE_STATUS_REG);
+	dev_info(&client->dev, "Device Status Register: 0x%x\n", status);
+
+	sens = synaptics_i2c_reg_get(client, SENSOR_SENSITIVITY_REG);
+	dev_info(&client->dev, "Sensor Sensitivity: 0x%x\n", sens);
+
+	for (retry_count = 0; retry_count < 3; retry_count++) {
+		ret = synaptics_i2c_block_read(client, PRODUCT_ID_REG0,
+					       sizeof(id), id);
+		if (ret != sizeof(id))
+			continue;
+
+		dev_info(&client->dev, "Product ID: %s\n", id);
+		break;
+	}
+
+	return 0;
+}
+
+static int synaptics_i2c_config(struct i2c_client *client)
+{
+	int ret, control;
+	u8 int_en;
+
+	/* set Report Rate to 40 and Sleep to normal */
+	ret = synaptics_i2c_reg_set(client, DEV_CONTROL_REG, 0x41);
+	if (ret)
+		return ret;
+
+	/* set Interrupt Disable to Func20 / Enable to Func10) */
+	int_en = (polling_req) ? 0 : INT_ENA_ABS_MSK | INT_ENA_REL_MSK;
+	ret = synaptics_i2c_reg_set(client, INTERRUPT_EN_REG, int_en);
+	if (ret)
+		return ret;
+
+	control = synaptics_i2c_reg_get(client, GENERAL_2D_CONTROL_REG);
+	/* No Deceleration */
+	control |= (no_decel) ? 1 << NO_DECELERATION : 0;
+	/* Reduced Reporting */
+	control |= (reduce_report) ? 1 << REDUCE_REPORTING : 0;
+	/* No Filter */
+	control |= (no_filter) ? 1 << NO_FILTER : 0;
+	ret = synaptics_i2c_reg_set(client, GENERAL_2D_CONTROL_REG, control);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int synaptics_i2c_reset_config(struct i2c_client *client)
+{
+	int ret;
+	/* Reset the Touchpad */
+	ret = synaptics_i2c_reg_set(client, DEV_COMMAND_REG, RESET_COMMAND);
+	if (ret) {
+		dev_err(&client->dev, "Unable to reset device\n");
+	} else {
+		mdelay(SOFT_RESET_DELAY_MS);
+		ret = synaptics_i2c_config(client);
+		if (ret)
+			dev_err(&client->dev, "Unable to config device\n");
+	}
+
+	return ret;
+}
+
+static int synaptics_i2c_check_error(struct i2c_client *client)
+{
+	int status, ret = 0;
+
+	status = i2c_smbus_read_byte_data(client, DEVICE_STATUS_REG) &
+		(CONFIGURED_MSK | ERROR_MSK);
+	if (status != CONFIGURED_MSK)
+		ret = synaptics_i2c_reset_config(client);
+
+	return ret;
+}
+
+static int synaptics_i2c_get_input(struct synaptics_i2c *touch)
+{
+	struct input_dev *input = touch->input;
+	int xy_delta, gesture;
+	s8 x_delta, y_delta;
+
+	/* Deal with spontanious resets and errors */
+	if (synaptics_i2c_check_error(touch->client))
+		return 0;
+
+	/* Get Gesture Bit */
+	gesture = GET_BIT(GESTURE,
+			  synaptics_i2c_reg_get(touch->client, DATA_REG0));
+
+	/* Get Relative axes. According to RMI Manual, we have to get */
+	/* them in one shot, so we get 2 bytes starting from REL_X_REG. */
+	xy_delta = synaptics_i2c_word_get(touch->client, REL_X_REG) & 0xffff;
+
+	/* Separate X from Y */
+	x_delta = xy_delta & 0xff;
+	y_delta = (xy_delta >> REGISTER_LENGTH) & 0xff;
+
+	/* Report the button event */
+	if (gesture)
+		input_report_key(input, BTN_LEFT, 1);
+	else
+		input_report_key(input, BTN_LEFT, 0);
+
+	/* Report the deltas multiplied by acceleration factor */
+	input_report_rel(input, REL_X,
+			 (touch->accel * (s16) x_delta) / ACCEL_DIVIDER);
+	input_report_rel(input, REL_Y,
+			 -((touch->accel * (s16) y_delta) / ACCEL_DIVIDER));
+	input_sync(input);
+
+	return ((xy_delta || gesture) ? 1 : 0);
+}
+
+static irqreturn_t synaptics_i2c_irq(int irq, void *_touch)
+{
+	struct synaptics_i2c *touch = _touch;
+
+	complete(&touch->touch_completion);
+
+	return IRQ_HANDLED;
+}
+
+static void synaptics_i2c_check_params(struct synaptics_i2c *touch)
+{
+	int reset = 0;
+	if (accel != touch->accel_param)
+		set_acceleration(touch, accel);
+
+	if (scan_rate != touch->scan_rate_param)
+		set_scan_rate(touch, scan_rate);
+
+	if (no_decel != touch->no_decel_param) {
+		touch->no_decel_param = no_decel;
+		reset = 1;
+	}
+	if (no_filter != touch->no_filter_param) {
+		touch->no_filter_param = no_filter;
+		reset = 1;
+	}
+	if (reduce_report != touch->reduce_report_param) {
+		touch->reduce_report_param = reduce_report;
+		reset = 1;
+	}
+	if (reset)
+		synaptics_i2c_reset_config(touch->client);
+}
+
+/* Control the Thread sleep time */
+unsigned long synaptics_i2c_fix_delay(struct synaptics_i2c *touch, int data)
+{
+	int delay, nodata_count_thres;
+
+	if (polling_req) {
+		delay = touch->scan_ms;
+		if (data)
+			touch->no_data_count = 0;
+		else {
+			nodata_count_thres = NO_DATA_THRES / touch->scan_ms;
+			if (touch->no_data_count < nodata_count_thres)
+				touch->no_data_count++;
+			else
+				delay = NO_DATA_SLEEP_MSECS;
+		}
+	} else
+		delay = THREAD_IRQ_SLEEP_MSECS;
+
+	return msecs_to_jiffies(delay);
+}
+
+/* The Thread */
+static int synaptics_i2c_touchd(void *_touch)
+{
+	struct synaptics_i2c *touch = _touch;
+	unsigned long sleep_delay;
+	int data = 1;
+
+	sleep_delay = synaptics_i2c_fix_delay(touch, data);
+
+	daemonize("synaptics_i2cd");
+	while (!kthread_should_stop()) {
+		if (touch->thread_stop)
+			break;
+		synaptics_i2c_check_params(touch);
+
+		wait_for_completion_interruptible_timeout(&touch->touch_completion, sleep_delay);
+
+		if (touch->thread_stop)
+			break;
+
+		try_to_freeze();
+		if (!touch->suspend_link) {
+			do {
+				data = synaptics_i2c_get_input(touch);
+				sleep_delay = synaptics_i2c_fix_delay(touch, data);
+			} while (data);
+		}
+	}
+	complete_and_exit(&touch->thread_completion, 0);
+}
+
+struct synaptics_i2c *synaptics_i2c_touch_create(struct i2c_client *client)
+{
+	struct synaptics_i2c *touch;
+
+	touch = kzalloc(sizeof(struct synaptics_i2c), GFP_KERNEL);
+	if (!touch)
+		return NULL;
+
+	memset(touch, 0, sizeof(struct synaptics_i2c));
+	touch->client = client;
+	touch->no_decel_param = no_decel;
+	touch->scan_rate_param = scan_rate;
+	set_scan_rate(touch, scan_rate);
+	touch->accel_param = accel;
+	set_acceleration(touch, accel);
+	init_completion(&touch->touch_completion);
+	init_completion(&touch->thread_completion);
+
+	return touch;
+}
+
+static int synaptics_i2c_suspend(struct i2c_client *client, pm_message_t mesg)
+{
+	struct synaptics_i2c *touch = i2c_get_clientdata(client);
+
+	/* We don't want timeouts on i2c bus */
+	touch->suspend_link = 1;
+
+	return 0;
+}
+
+static int synaptics_i2c_resume(struct i2c_client *client)
+{
+	int ret;
+	struct synaptics_i2c *touch = i2c_get_clientdata(client);
+
+	ret = synaptics_i2c_reset_config(client);
+	touch->suspend_link = 0;
+
+	return ret;
+}
+
+static int synaptics_i2c_open(struct input_dev *input)
+{
+	int ret = 0;
+	struct synaptics_i2c *touch = input_get_drvdata(input);
+
+	if (touch->users_count++)
+		return 0;
+
+	ret = synaptics_i2c_reset_config(touch->client);
+	if (ret)
+		return ret;
+
+	if (!polling_req) {
+		ret = request_irq(touch->client->irq, synaptics_i2c_irq,
+				  IRQF_DISABLED|IRQ_TYPE_EDGE_FALLING,
+				  DRIVER_NAME, touch);
+		if (ret) {
+			dev_warn(&touch->client->dev,
+				  "IRQ request failed: %d\n"
+				  "Trying to use polling...\n", ret);
+			polling_req = 1;
+		}
+	}
+	touch->thread_stop = 0;
+	touch->thread = kthread_run(&synaptics_i2c_touchd,
+				     touch, "synaptics_i2cd");
+	if (IS_ERR(touch->thread)) {
+		ret = PTR_ERR(touch->thread);
+		touch->thread = NULL;
+	}
+	/* FIXME: Should we do something with the device here? */
+
+	return ret;
+}
+
+static void synaptics_i2c_close(struct input_dev *input)
+{
+	struct synaptics_i2c *touch = input_get_drvdata(input);
+
+	if (--touch->users_count)
+		return;
+
+	if (!touch->users_count) {
+		touch->thread_stop = 1;
+		complete(&touch->touch_completion); /* Awake the thread */
+		wait_for_completion(&touch->thread_completion);
+		touch->thread = NULL;
+
+		if (!polling_req)
+			free_irq(touch->client->irq, touch);
+
+	/* FIXME: Should we do something with the device here? */
+	}
+}
+
+static void synaptics_i2c_set_input_params(struct synaptics_i2c *touch)
+{
+	struct input_dev *input = touch->input;
+
+	input->name = touch->client->name;
+	input->phys = touch->client->adapter->name;
+	input->id.bustype = BUS_I2C;
+	input->id.version = synaptics_i2c_word_get(touch->client,
+						   INFO_QUERY_REG0);
+	input->dev.parent = &touch->client->dev;
+	input->open = synaptics_i2c_open;
+	input->close = synaptics_i2c_close;
+	input_set_drvdata(input, touch);
+
+	/* Register the device as mouse */
+	set_bit(EV_REL, input->evbit);
+	set_bit(REL_X, input->relbit);
+	set_bit(REL_Y, input->relbit);
+
+	/* Register device's buttons and keys */
+	set_bit(EV_KEY, input->evbit);
+	set_bit(BTN_LEFT, input->keybit);
+}
+
+static const struct i2c_device_id synaptics_i2c_id_table[] = {
+	{ DRIVER_NAME, 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, synaptics_i2c_id_table);
+
+static int synaptics_i2c_probe(struct i2c_client *client,
+			       const struct i2c_device_id *dev_id)
+{
+	int ret;
+	struct synaptics_i2c *touch = NULL;
+
+	ret = synaptics_i2c_reset_config(client);
+	if (ret)
+		return ret;
+
+	if (query) {
+		ret = synaptics_i2c_query(client);
+		if (ret) {
+			dev_err(&client->dev, "Query failed: %d\n", ret);
+			return ret;
+		}
+	}
+
+	touch = synaptics_i2c_touch_create(client);
+	if (!touch)
+		goto err_mem;
+
+	i2c_set_clientdata(client, touch);
+
+	if (client->irq < 1)
+		polling_req = 1;
+
+	touch->input = input_allocate_device();
+	if (!touch->input)
+		goto err_mem;
+
+	synaptics_i2c_set_input_params(touch);
+
+	if (!polling_req)
+		dev_info(&touch->client->dev,
+			  "IRQ will be used: %d\n", touch->client->irq);
+	else
+		dev_info(&touch->client->dev,
+			  "Using polling at rate: %d times/sec\n", scan_rate);
+
+	/* Register the device in input subsystem */
+	ret = input_register_device(touch->input);
+	if (ret) {
+		dev_err(&client->dev,
+			 "Input device register failed: %d\n", ret);
+		goto err_free;
+	}
+	return 0;
+
+err_mem:
+	dev_err(&client->dev, "Insufficient memory\n");
+	ret = -ENOMEM;
+
+err_free:
+	input_free_device(touch->input);
+	i2c_set_clientdata(client, NULL);
+	kfree(touch);
+
+	return ret;
+}
+
+static int __devexit synaptics_i2c_remove(struct i2c_client *client)
+{
+	struct synaptics_i2c *touch = i2c_get_clientdata(client);
+
+	input_unregister_device(touch->input);
+	i2c_set_clientdata(client, NULL);
+	kfree(touch);
+
+	return 0;
+}
+
+static struct i2c_driver synaptics_i2c_driver = {
+	.driver = {
+		.name	= DRIVER_NAME,
+		.owner	= THIS_MODULE,
+	},
+
+	.probe		= synaptics_i2c_probe,
+	.remove		= synaptics_i2c_remove,
+
+	.suspend	= synaptics_i2c_suspend,
+	.resume		= synaptics_i2c_resume,
+	.id_table	= synaptics_i2c_id_table,
+};
+
+static int __init synaptics_i2c_init(void)
+{
+	return i2c_add_driver(&synaptics_i2c_driver);
+}
+
+static void __exit synaptics_i2c_exit(void)
+{
+	i2c_del_driver(&synaptics_i2c_driver);
+}
+
+module_init(synaptics_i2c_init);
+module_exit(synaptics_i2c_exit);
+
+MODULE_DESCRIPTION("Synaptics I2C touchpad driver");
+MODULE_AUTHOR("Mike Rapoport, Igor Grinberg, Compulab");
+MODULE_LICENSE("GPL");
-- 
1.6.0.6