/*
* Driver for EETI eGalax Multiple Touch Controller
*
* Copyright (C) 2011 Freescale Semiconductor, Inc.
*
* based on max11801_ts.c
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
/* EETI eGalax serial touch screen controller is a I2C based multiple
* touch screen controller, it supports 5 point multiple touch. */
/* TODO:
- auto idle mode support
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/irq.h>
#include <linux/gpio.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/bitops.h>
#include <linux/input/mt.h>
/*
* Mouse Mode: some panel may configure the controller to mouse mode,
* which can only report one point at a given time.
* This driver will ignore events in this mode.
*/
#define REPORT_MODE_MOUSE 0x1
/*
* Vendor Mode: this mode is used to transfer some vendor specific
* messages.
* This driver will ignore events in this mode.
*/
#define REPORT_MODE_VENDOR 0x3
/* Multiple Touch Mode */
#define REPORT_MODE_MTTOUCH 0x4
#define MAX_SUPPORT_POINTS 5
#define EVENT_VALID_OFFSET 7
#define EVENT_VALID_MASK (0x1 << EVENT_VALID_OFFSET)
#define EVENT_ID_OFFSET 2
#define EVENT_ID_MASK (0xf << EVENT_ID_OFFSET)
#define EVENT_IN_RANGE (0x1 << 1)
#define EVENT_DOWN_UP (0X1 << 0)
#define MAX_I2C_DATA_LEN 10
#define EGALAX_MAX_X 32760
#define EGALAX_MAX_Y 32760
#define EGALAX_MAX_TRIES 100
struct egalax_ts {
struct i2c_client *client;
struct input_dev *input_dev;
};
static irqreturn_t egalax_ts_interrupt(int irq, void *dev_id)
{
struct egalax_ts *ts = dev_id;
struct input_dev *input_dev = ts->input_dev;
struct i2c_client *client = ts->client;
u8 buf[MAX_I2C_DATA_LEN];
int id, ret, x, y, z;
int tries = 0;
bool down, valid;
u8 state;
do {
ret = i2c_master_recv(client, buf, MAX_I2C_DATA_LEN);
} while (ret == -EAGAIN && tries++ < EGALAX_MAX_TRIES);
if (ret < 0)
return IRQ_HANDLED;
if (buf[0] != REPORT_MODE_MTTOUCH) {
/* ignore mouse events and vendor events */
return IRQ_HANDLED;
}
state = buf[1];
x = (buf[3] << 8) | buf[2];
y = (buf[5] << 8) | buf[4];
z = (buf[7] << 8) | buf[6];
valid = state & EVENT_VALID_MASK;
id = (state & EVENT_ID_MASK) >> EVENT_ID_OFFSET;
down = state & EVENT_DOWN_UP;
if (!valid || id > MAX_SUPPORT_POINTS) {
dev_dbg(&client->dev, "point invalid\n");
return IRQ_HANDLED;
}
input_mt_slot(input_dev, id);
input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, down);
dev_dbg(&client->dev, "%s id:%d x:%d y:%d z:%d",
down ? "down" : "up", id, x, y, z);
if (down) {
input_report_abs(input_dev, ABS_MT_POSITION_X, x);
input_report_abs(input_dev, ABS_MT_POSITION_Y, y);
input_report_abs(input_dev, ABS_MT_PRESSURE, z);
}
input_mt_report_pointer_emulation(input_dev, true);
input_sync(input_dev);
return IRQ_HANDLED;
}
/* wake up controller by an falling edge of interrupt gpio. */
static int egalax_wake_up_device(struct i2c_client *client)
{
int gpio = irq_to_gpio(client->irq);
int ret;
ret = gpio_request(gpio, "egalax_irq");
if (ret < 0) {
dev_err(&client->dev,
"request gpio failed, cannot wake up controller: %d\n",
ret);
return ret;
}
/* wake up controller via an falling edge on IRQ gpio. */
gpio_direction_output(gpio, 0);
gpio_set_value(gpio, 1);
/* controller should be waken up, return irq. */
gpio_direction_input(gpio);
gpio_free(gpio);
return 0;
}
static int __devinit egalax_firmware_version(struct i2c_client *client)
{
static const u8 cmd[MAX_I2C_DATA_LEN] = { 0x03, 0x03, 0xa, 0x01, 0x41 };
int ret;
ret = i2c_master_send(client, cmd, MAX_I2C_DATA_LEN);
if (ret < 0)
return ret;
return 0;
}
static int __devinit egalax_ts_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct egalax_ts *ts;
struct input_dev *input_dev;
int ret;
int error;
ts = kzalloc(sizeof(struct egalax_ts), GFP_KERNEL);
if (!ts) {
dev_err(&client->dev, "Failed to allocate memory\n");
return -ENOMEM;
}
input_dev = input_allocate_device();
if (!input_dev) {
dev_err(&client->dev, "Failed to allocate memory\n");
error = -ENOMEM;
goto err_free_ts;
}
ts->client = client;
ts->input_dev = input_dev;
/* controller may be in sleep, wake it up. */
egalax_wake_up_device(client);
ret = egalax_firmware_version(client);
if (ret < 0) {
dev_err(&client->dev, "Failed to read firmware version\n");
error = -EIO;
goto err_free_dev;
}
input_dev->name = "EETI eGalax Touch Screen";
input_dev->id.bustype = BUS_I2C;
input_dev->dev.parent = &client->dev;
__set_bit(EV_ABS, input_dev->evbit);
__set_bit(EV_KEY, input_dev->evbit);
__set_bit(BTN_TOUCH, input_dev->keybit);
input_set_abs_params(input_dev, ABS_X, 0, EGALAX_MAX_X, 0, 0);
input_set_abs_params(input_dev, ABS_Y, 0, EGALAX_MAX_Y, 0, 0);
input_set_abs_params(input_dev,
ABS_MT_POSITION_X, 0, EGALAX_MAX_X, 0, 0);
input_set_abs_params(input_dev,
ABS_MT_POSITION_X, 0, EGALAX_MAX_Y, 0, 0);
input_mt_init_slots(input_dev, MAX_SUPPORT_POINTS);
input_set_drvdata(input_dev, ts);
error = request_threaded_irq(client->irq, NULL, egalax_ts_interrupt,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
"egalax_ts", ts);
if (error < 0) {
dev_err(&client->dev, "Failed to register interrupt\n");
goto err_free_dev;
}
error = input_register_device(ts->input_dev);
if (error)
goto err_free_irq;
i2c_set_clientdata(client, ts);
return 0;
err_free_irq:
free_irq(client->irq, ts);
err_free_dev:
input_free_device(input_dev);
err_free_ts:
kfree(ts);
return error;
}
static __devexit int egalax_ts_remove(struct i2c_client *client)
{
struct egalax_ts *ts = i2c_get_clientdata(client);
free_irq(client->irq, ts);
input_unregister_device(ts->input_dev);
kfree(ts);
return 0;
}
static const struct i2c_device_id egalax_ts_id[] = {
{ "egalax_ts", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, egalax_ts_id);
#ifdef CONFIG_PM_SLEEP
static int egalax_ts_suspend(struct device *dev)
{
static const u8 suspend_cmd[MAX_I2C_DATA_LEN] = {
0x3, 0x6, 0xa, 0x3, 0x36, 0x3f, 0x2, 0, 0, 0
};
struct i2c_client *client = to_i2c_client(dev);
int ret;
ret = i2c_master_send(client, suspend_cmd, MAX_I2C_DATA_LEN);
return ret > 0 ? 0 : ret;
}
static int egalax_ts_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
return egalax_wake_up_device(client);
}
#endif
static SIMPLE_DEV_PM_OPS(egalax_ts_pm_ops, egalax_ts_suspend, egalax_ts_resume);
static struct i2c_driver egalax_ts_driver = {
.driver = {
.name = "egalax_ts",
.owner = THIS_MODULE,
.pm = &egalax_ts_pm_ops,
},
.id_table = egalax_ts_id,
.probe = egalax_ts_probe,
.remove = __devexit_p(egalax_ts_remove),
};
static int __init egalax_ts_init(void)
{
return i2c_add_driver(&egalax_ts_driver);
}
static void __exit egalax_ts_exit(void)
{
i2c_del_driver(&egalax_ts_driver);
}
module_init(egalax_ts_init);
module_exit(egalax_ts_exit);
MODULE_AUTHOR("Freescale Semiconductor, Inc.");
MODULE_DESCRIPTION("Touchscreen driver for EETI eGalax touch controller");
MODULE_LICENSE("GPL");
