/*
* 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>
#include <linux/slab.h>
#include <linux/pm.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 bool 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 bool 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 bool 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 bool 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;
spinlock_t lock;
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 void synaptics_i2c_reschedule_work(struct synaptics_i2c *touch,
unsigned long delay)
{
unsigned long flags;
spin_lock_irqsave(&touch->lock, flags);
/*
* If work is already scheduled then subsequent schedules will not
* change the scheduled time that's why we have to cancel it first.
*/
__cancel_delayed_work(&touch->dwork);
schedule_delayed_work(&touch->dwork, delay);
spin_unlock_irqrestore(&touch->lock, flags);
}
static irqreturn_t synaptics_i2c_irq(int irq, void *dev_id)
{
struct synaptics_i2c *touch = dev_id;
synaptics_i2c_reschedule_work(touch, 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 */
static 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
* necessarily 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.
*/
synaptics_i2c_reschedule_work(touch, 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)
synaptics_i2c_reschedule_work(touch,
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);
}
static 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);
spin_lock_init(&touch->lock);
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;
ret = synaptics_i2c_reset_config(client);
if (ret)
goto err_mem_free;
if (client->irq < 1)
polling_req = true;
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,
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 = true;
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;
}
i2c_set_clientdata(client, touch);
return 0;
err_input_free:
input_free_device(touch->input);
err_mem_free:
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(client->irq, touch);
input_unregister_device(touch->input);
kfree(touch);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int synaptics_i2c_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
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 device *dev)
{
int ret;
struct i2c_client *client = to_i2c_client(dev);
struct synaptics_i2c *touch = i2c_get_clientdata(client);
ret = synaptics_i2c_reset_config(client);
if (ret)
return ret;
synaptics_i2c_reschedule_work(touch,
msecs_to_jiffies(NO_DATA_SLEEP_MSECS));
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(synaptics_i2c_pm, synaptics_i2c_suspend,
synaptics_i2c_resume);
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,
.pm = &synaptics_i2c_pm,
},
.probe = synaptics_i2c_probe,
.remove = __devexit_p(synaptics_i2c_remove),
.id_table = synaptics_i2c_id_table,
};
module_i2c_driver(synaptics_i2c_driver);
MODULE_DESCRIPTION("Synaptics I2C touchpad driver");
MODULE_AUTHOR("Mike Rapoport, Igor Grinberg, Compulab");
MODULE_LICENSE("GPL");
