1 files changed, 676 insertions, 0 deletions

diff --git a/drivers/input/mouse/synaptics_i2c.c b/drivers/input/mouse/synaptics_i2c.c
new file mode 100644
index 000000000000..eac9fdde7ee9
--- /dev/null
+++ b/drivers/input/mouse/synaptics_i2c.c
@@ -0,0 +1,676 @@
+/*
+ * 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/i2c.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/input.h>
+#include <linux/delay.h>
+#include <linux/workqueue.h>
+
+#define DRIVER_NAME             "synaptics_i2c"
+/* maximum product id is 15 characters */
+#define PRODUCT_ID_LENGTH       15
+#define REGISTER_LENGTH         8
+
+/*
+ * 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
+
+/* Registers by SMBus address */
+#define PAGE_SEL_REG            0xff
+#define DEVICE_STATUS_REG       0x09
+
+/* 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)
+
+/* 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
+
+/* Function Masks */
+/* Device Control Register Masks (DEV_CONTROL_REG) */
+#define REPORT_RATE_MSK         0xc0
+#define SLEEP_MODE_MSK          0x07
+
+/* Device Sleep Modes */
+#define FULL_AWAKE              0x0
+#define NORMAL_OP               0x1
+#define LOW_PWR_OP              0x2
+#define VERY_LOW_PWR_OP         0x3
+#define SENS_SLEEP              0x4
+#define SLEEP_MOD               0x5
+#define DEEP_SLEEP              0x6
+#define HIBERNATE               0x7
+
+/* 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)
+
+/* 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)");
+
+/*
+ * touchpad 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");
+
+/* The main device structure */
+struct synaptics_i2c {
+        struct i2c_client       *client;
+        struct input_dev        *input;
+        struct delayed_work     dwork;
+        int                     no_data_count;
+        int                     no_decel_param;
+        int                     reduce_report_param;
+        int                     no_filter_param;
+        int                     scan_rate_param;
+        int                     scan_ms;
+};
+
+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;
+}
+
+/*
+ * Driver's initial design makes no race condition possible on i2c bus,
+ * so there is no need in any locking.
+ * Keep it in mind, while playing with the code.
+ */
+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 == 0)
+                ret = i2c_smbus_read_byte_data(client, reg & 0xff);
+
+        return ret;
+}
+
+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 == 0)
+                ret = i2c_smbus_write_byte_data(client, reg & 0xff, val);
+
+        return ret;
+}
+
+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 == 0)
+                ret = i2c_smbus_read_word_data(client, reg & 0xff);
+
+        return ret;
+}
+
+static int synaptics_i2c_config(struct i2c_client *client)
+{
+        int ret, control;
+        u8 int_en;
+
+        /* set Report Rate to Device Highest (>=80) and Sleep to normal */
+        ret = synaptics_i2c_reg_set(client, DEV_CONTROL_REG, 0xc1);
+        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 {
+                msleep(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 bool synaptics_i2c_get_input(struct synaptics_i2c *touch)
+{
+        struct input_dev *input = touch->input;
+        int xy_delta, gesture;
+        s32 data;
+        s8 x_delta, y_delta;
+
+        /* Deal with spontanious resets and errors */
+        if (synaptics_i2c_check_error(touch->client))
+                return 0;
+
+        /* Get Gesture Bit */
+        data = synaptics_i2c_reg_get(touch->client, DATA_REG0);
+        gesture = (data >> GESTURE) & 0x1;
+
+        /*
+         * Get Relative axes. 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 */
+        input_report_key(input, BTN_LEFT, gesture);
+
+        /* Report the deltas */
+        input_report_rel(input, REL_X, x_delta);
+        input_report_rel(input, REL_Y, -y_delta);
+        input_sync(input);
+
+        return xy_delta || gesture;
+}
+
+static irqreturn_t synaptics_i2c_irq(int irq, void *dev_id)
+{
+        struct synaptics_i2c *touch = dev_id;
+
+        /*
+         * We want to have the work run immediately but it might have
+         * already been scheduled with a delay, that's why we have to
+         * cancel it first.
+         */
+        cancel_delayed_work(&touch->dwork);
+        schedule_delayed_work(&touch->dwork, 0);
+
+        return IRQ_HANDLED;
+}
+
+static void synaptics_i2c_check_params(struct synaptics_i2c *touch)
+{
+        bool reset = false;
+
+        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 = true;
+        }
+
+        if (no_filter != touch->no_filter_param) {
+                touch->no_filter_param = no_filter;
+                reset = true;
+        }
+
+        if (reduce_report != touch->reduce_report_param) {
+                touch->reduce_report_param = reduce_report;
+                reset = true;
+        }
+
+        if (reset)
+                synaptics_i2c_reset_config(touch->client);
+}
+
+/* Control the Device polling rate / Work Handler sleep time */
+unsigned long synaptics_i2c_adjust_delay(struct synaptics_i2c *touch,
+                                         bool have_data)
+{
+        unsigned long delay, nodata_count_thres;
+
+        if (polling_req) {
+                delay = touch->scan_ms;
+                if (have_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;
+                }
+                return msecs_to_jiffies(delay);
+        } else {
+                delay = msecs_to_jiffies(THREAD_IRQ_SLEEP_MSECS);
+                return round_jiffies_relative(delay);
+        }
+}
+
+/* Work Handler */
+static void synaptics_i2c_work_handler(struct work_struct *work)
+{
+        bool have_data;
+        struct synaptics_i2c *touch =
+                        container_of(work, struct synaptics_i2c, dwork.work);
+        unsigned long delay;
+
+        synaptics_i2c_check_params(touch);
+
+        have_data = synaptics_i2c_get_input(touch);
+        delay = synaptics_i2c_adjust_delay(touch, have_data);
+
+        /*
+         * While interrupt driven, there is no real need to poll the device.
+         * But touchpads are very sensitive, so there could be errors
+         * related to physical environment and the attention line isn't
+         * neccesarily asserted. In such case we can lose the touchpad.
+         * We poll the device once in THREAD_IRQ_SLEEP_SECS and
+         * if error is detected, we try to reset and reconfigure the touchpad.
+         */
+        schedule_delayed_work(&touch->dwork, delay);
+}
+
+static int synaptics_i2c_open(struct input_dev *input)
+{
+        struct synaptics_i2c *touch = input_get_drvdata(input);
+        int ret;
+
+        ret = synaptics_i2c_reset_config(touch->client);
+        if (ret)
+                return ret;
+
+        if (polling_req)
+                schedule_delayed_work(&touch->dwork,
+                                       msecs_to_jiffies(NO_DATA_SLEEP_MSECS));
+
+        return 0;
+}
+
+static void synaptics_i2c_close(struct input_dev *input)
+{
+        struct synaptics_i2c *touch = input_get_drvdata(input);
+
+        if (!polling_req)
+                synaptics_i2c_reg_set(touch->client, INTERRUPT_EN_REG, 0);
+
+        cancel_delayed_work_sync(&touch->dwork);
+
+        /* Save some power */
+        synaptics_i2c_reg_set(touch->client, DEV_CONTROL_REG, DEEP_SLEEP);
+}
+
+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);
+}
+
+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;
+
+        touch->client = client;
+        touch->no_decel_param = no_decel;
+        touch->scan_rate_param = scan_rate;
+        set_scan_rate(touch, scan_rate);
+        INIT_DELAYED_WORK(&touch->dwork, synaptics_i2c_work_handler);
+
+        return touch;
+}
+
+static int __devinit synaptics_i2c_probe(struct i2c_client *client,
+                               const struct i2c_device_id *dev_id)
+{
+        int ret;
+        struct synaptics_i2c *touch;
+
+        touch = synaptics_i2c_touch_create(client);
+        if (!touch)
+                return -ENOMEM;
+
+        i2c_set_clientdata(client, touch);
+
+        ret = synaptics_i2c_reset_config(client);
+        if (ret)
+                goto err_mem_free;
+
+        if (client->irq < 1)
+                polling_req = 1;
+
+        touch->input = input_allocate_device();
+        if (!touch->input) {
+                ret = -ENOMEM;
+                goto err_mem_free;
+        }
+
+        synaptics_i2c_set_input_params(touch);
+
+        if (!polling_req) {
+                dev_dbg(&touch->client->dev,
+                         "Requesting IRQ: %d\n", touch->client->irq);
+
+                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, "
+                                  "falling back to polling\n", ret);
+                        polling_req = 1;
+                        synaptics_i2c_reg_set(touch->client,
+                                              INTERRUPT_EN_REG, 0);
+                }
+        }
+
+        if (polling_req)
+                dev_dbg(&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_input_free;
+        }
+        return 0;
+
+err_input_free:
+        input_free_device(touch->input);
+err_mem_free:
+        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);
+
+        if (!polling_req)
+                free_irq(touch->client->irq, touch);
+
+        input_unregister_device(touch->input);
+        i2c_set_clientdata(client, NULL);
+        kfree(touch);
+
+        return 0;
+}
+
+#ifdef CONFIG_PM
+static int synaptics_i2c_suspend(struct i2c_client *client, pm_message_t mesg)
+{
+        struct synaptics_i2c *touch = i2c_get_clientdata(client);
+
+        cancel_delayed_work_sync(&touch->dwork);
+
+        /* Save some power */
+        synaptics_i2c_reg_set(touch->client, DEV_CONTROL_REG, DEEP_SLEEP);
+
+        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);
+        if (ret)
+                return ret;
+
+        schedule_delayed_work(&touch->dwork,
+                               msecs_to_jiffies(NO_DATA_SLEEP_MSECS));
+
+        return 0;
+}
+#else
+#define synaptics_i2c_suspend   NULL
+#define synaptics_i2c_resume    NULL
+#endif
+
+static const struct i2c_device_id synaptics_i2c_id_table[] = {
+        { "synaptics_i2c", 0 },
+        { },
+};
+MODULE_DEVICE_TABLE(i2c, synaptics_i2c_id_table);
+
+static struct i2c_driver synaptics_i2c_driver = {
+        .driver = {
+                .name   = DRIVER_NAME,
+                .owner  = THIS_MODULE,
+        },
+
+        .probe          = synaptics_i2c_probe,
+        .remove         = __devexit_p(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");
+