/*
* ST1232 Touchscreen Controller Driver
*
* Copyright (C) 2010 Renesas Solutions Corp.
* Tony SIM <chinyeow.sim.xt@renesas.com>
*
* Using code from:
* - android.git.kernel.org: projects/kernel/common.git: synaptics_i2c_rmi.c
* Copyright (C) 2007 Google, Inc.
*
* This software is licensed under the terms of the GNU General Public
* License version 2, as published by the Free Software Foundation, and
* may be copied, distributed, and modified under those terms.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/pm_qos.h>
#include <linux/slab.h>
#include <linux/types.h>
#define ST1232_TS_NAME "st1232-ts"
#define MIN_X 0x00
#define MIN_Y 0x00
#define MAX_X 0x31f /* (800 - 1) */
#define MAX_Y 0x1df /* (480 - 1) */
#define MAX_AREA 0xff
#define MAX_FINGERS 2
struct st1232_ts_finger {
u16 x;
u16 y;
u8 t;
bool is_valid;
};
struct st1232_ts_data {
struct i2c_client *client;
struct input_dev *input_dev;
struct st1232_ts_finger finger[MAX_FINGERS];
struct dev_pm_qos_request low_latency_req;
};
static int st1232_ts_read_data(struct st1232_ts_data *ts)
{
struct st1232_ts_finger *finger = ts->finger;
struct i2c_client *client = ts->client;
struct i2c_msg msg[2];
int error;
u8 start_reg;
u8 buf[10];
/* read touchscreen data from ST1232 */
msg[0].addr = client->addr;
msg[0].flags = 0;
msg[0].len = 1;
msg[0].buf = &start_reg;
start_reg = 0x10;
msg[1].addr = ts->client->addr;
msg[1].flags = I2C_M_RD;
msg[1].len = sizeof(buf);
msg[1].buf = buf;
error = i2c_transfer(client->adapter, msg, 2);
if (error < 0)
return error;
/* get "valid" bits */
finger[0].is_valid = buf[2] >> 7;
finger[1].is_valid = buf[5] >> 7;
/* get xy coordinate */
if (finger[0].is_valid) {
finger[0].x = ((buf[2] & 0x0070) << 4) | buf[3];
finger[0].y = ((buf[2] & 0x0007) << 8) | buf[4];
finger[0].t = buf[8];
}
if (finger[1].is_valid) {
finger[1].x = ((buf[5] & 0x0070) << 4) | buf[6];
finger[1].y = ((buf[5] & 0x0007) << 8) | buf[7];
finger[1].t = buf[9];
}
return 0;
}
static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id)
{
struct st1232_ts_data *ts = dev_id;
struct st1232_ts_finger *finger = ts->finger;
struct input_dev *input_dev = ts->input_dev;
int count = 0;
int i, ret;
ret = st1232_ts_read_data(ts);
if (ret < 0)
goto end;
/* multi touch protocol */
for (i = 0; i < MAX_FINGERS; i++) {
if (!finger[i].is_valid)
continue;
input_report_abs(input_dev, ABS_MT_TOUCH_MAJOR, finger[i].t);
input_report_abs(input_dev, ABS_MT_POSITION_X, finger[i].x);
input_report_abs(input_dev, ABS_MT_POSITION_Y, finger[i].y);
input_mt_sync(input_dev);
count++;
}
/* SYN_MT_REPORT only if no contact */
if (!count) {
input_mt_sync(input_dev);
if (ts->low_latency_req.dev) {
dev_pm_qos_remove_request(&ts->low_latency_req);
ts->low_latency_req.dev = NULL;
}
} else if (!ts->low_latency_req.dev) {
/* First contact, request 100 us latency. */
dev_pm_qos_add_ancestor_request(&ts->client->dev,
&ts->low_latency_req, 100);
}
/* SYN_REPORT */
input_sync(input_dev);
end:
return IRQ_HANDLED;
}
static int st1232_ts_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct st1232_ts_data *ts;
struct input_dev *input_dev;
int error;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
dev_err(&client->dev, "need I2C_FUNC_I2C\n");
return -EIO;
}
if (!client->irq) {
dev_err(&client->dev, "no IRQ?\n");
return -EINVAL;
}
ts = kzalloc(sizeof(struct st1232_ts_data), GFP_KERNEL);
input_dev = input_allocate_device();
if (!ts || !input_dev) {
error = -ENOMEM;
goto err_free_mem;
}
ts->client = client;
ts->input_dev = input_dev;
input_dev->name = "st1232-touchscreen";
input_dev->id.bustype = BUS_I2C;
input_dev->dev.parent = &client->dev;
__set_bit(EV_SYN, input_dev->evbit);
__set_bit(EV_KEY, input_dev->evbit);
__set_bit(EV_ABS, input_dev->evbit);
input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, MAX_AREA, 0, 0);
input_set_abs_params(input_dev, ABS_MT_POSITION_X, MIN_X, MAX_X, 0, 0);
input_set_abs_params(input_dev, ABS_MT_POSITION_Y, MIN_Y, MAX_Y, 0, 0);
error = request_threaded_irq(client->irq, NULL, st1232_ts_irq_handler,
IRQF_ONESHOT, client->name, ts);
if (error) {
dev_err(&client->dev, "Failed to register interrupt\n");
goto err_free_mem;
}
error = input_register_device(ts->input_dev);
if (error) {
dev_err(&client->dev, "Unable to register %s input device\n",
input_dev->name);
goto err_free_irq;
}
i2c_set_clientdata(client, ts);
device_init_wakeup(&client->dev, 1);
return 0;
err_free_irq:
free_irq(client->irq, ts);
err_free_mem:
input_free_device(input_dev);
kfree(ts);
return error;
}
static int st1232_ts_remove(struct i2c_client *client)
{
struct st1232_ts_data *ts = i2c_get_clientdata(client);
device_init_wakeup(&client->dev, 0);
free_irq(client->irq, ts);
input_unregister_device(ts->input_dev);
kfree(ts);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int st1232_ts_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
if (device_may_wakeup(&client->dev))
enable_irq_wake(client->irq);
else
disable_irq(client->irq);
return 0;
}
static int st1232_ts_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
if (device_may_wakeup(&client->dev))
disable_irq_wake(client->irq);
else
enable_irq(client->irq);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops,
st1232_ts_suspend, st1232_ts_resume);
static const struct i2c_device_id st1232_ts_id[] = {
{ ST1232_TS_NAME, 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, st1232_ts_id);
#ifdef CONFIG_OF
static const struct of_device_id st1232_ts_dt_ids[] = {
{ .compatible = "sitronix,st1232", },
{ }
};
MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids);
#endif
static struct i2c_driver st1232_ts_driver = {
.probe = st1232_ts_probe,
.remove = st1232_ts_remove,
.id_table = st1232_ts_id,
.driver = {
.name = ST1232_TS_NAME,
.owner = THIS_MODULE,
.of_match_table = of_match_ptr(st1232_ts_dt_ids),
.pm = &st1232_ts_pm_ops,
},
};
module_i2c_driver(st1232_ts_driver);
MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>");
MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver");
MODULE_LICENSE("GPL");
