/*
* Touch Screen driver for Renesas MIGO-R Platform
*
* Copyright (c) 2008 Magnus Damm
* Copyright (c) 2007 Ujjwal Pande <ujjwal@kenati.com>,
* Kenati Technologies Pvt Ltd.
*
* This file is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This file 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.
*
* You should have received a copy of the GNU General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <asm/io.h>
#include <linux/i2c.h>
#include <linux/timer.h>
#define EVENT_PENDOWN 1
#define EVENT_REPEAT 2
#define EVENT_PENUP 3
struct migor_ts_priv {
struct i2c_client *client;
struct input_dev *input;
struct delayed_work work;
int irq;
};
static const u_int8_t migor_ts_ena_seq[17] = { 0x33, 0x22, 0x11,
0x01, 0x06, 0x07, };
static const u_int8_t migor_ts_dis_seq[17] = { };
static void migor_ts_poscheck(struct work_struct *work)
{
struct migor_ts_priv *priv = container_of(work,
struct migor_ts_priv,
work.work);
unsigned short xpos, ypos;
unsigned char event;
u_int8_t buf[16];
memset(buf, 0, sizeof(buf));
/* Set Index 0 */
buf[0] = 0;
if (i2c_master_send(priv->client, buf, 1) != 1) {
dev_err(&priv->client->dev, "Unable to write i2c index\n");
goto out;
}
/* Now do Page Read */
if (i2c_master_recv(priv->client, buf, sizeof(buf)) != sizeof(buf)) {
dev_err(&priv->client->dev, "Unable to read i2c page\n");
goto out;
}
ypos = ((buf[9] & 0x03) << 8 | buf[8]);
xpos = ((buf[11] & 0x03) << 8 | buf[10]);
event = buf[12];
if (event == EVENT_PENDOWN || event == EVENT_REPEAT) {
input_report_key(priv->input, BTN_TOUCH, 1);
input_report_abs(priv->input, ABS_X, ypos); /*X-Y swap*/
input_report_abs(priv->input, ABS_Y, xpos);
input_sync(priv->input);
} else if (event == EVENT_PENUP) {
input_report_key(priv->input, BTN_TOUCH, 0);
input_sync(priv->input);
}
out:
enable_irq(priv->irq);
}
static irqreturn_t migor_ts_isr(int irq, void *dev_id)
{
struct migor_ts_priv *priv = dev_id;
/* the touch screen controller chip is hooked up to the cpu
* using i2c and a single interrupt line. the interrupt line
* is pulled low whenever someone taps the screen. to deassert
* the interrupt line we need to acknowledge the interrupt by
* communicating with the controller over the slow i2c bus.
*
* we can't acknowledge from interrupt context since the i2c
* bus controller may sleep, so we just disable the interrupt
* here and handle the acknowledge using delayed work.
*/
disable_irq_nosync(irq);
schedule_delayed_work(&priv->work, HZ / 20);
return IRQ_HANDLED;
}
static int migor_ts_open(struct input_dev *dev)
{
struct migor_ts_priv *priv = input_get_drvdata(dev);
struct i2c_client *client = priv->client;
int count;
/* enable controller */
count = i2c_master_send(client, migor_ts_ena_seq,
sizeof(migor_ts_ena_seq));
if (count != sizeof(migor_ts_ena_seq)) {
dev_err(&client->dev, "Unable to enable touchscreen.\n");
return -ENXIO;
}
return 0;
}
static void migor_ts_close(struct input_dev *dev)
{
struct migor_ts_priv *priv = input_get_drvdata(dev);
struct i2c_client *client = priv->client;
disable_irq(priv->irq);
/* cancel pending work and wait for migor_ts_poscheck() to finish */
if (cancel_delayed_work_sync(&priv->work)) {
/*
* if migor_ts_poscheck was canceled we need to enable IRQ
* here to balance disable done in migor_ts_isr.
*/
enable_irq(priv->irq);
}
/* disable controller */
i2c_master_send(client, migor_ts_dis_seq, sizeof(migor_ts_dis_seq));
enable_irq(priv->irq);
}
static int migor_ts_probe(struct i2c_client *client,
const struct i2c_device_id *idp)
{
struct migor_ts_priv *priv;
struct input_dev *input;
int error;
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (!priv) {
dev_err(&client->dev, "failed to allocate driver data\n");
error = -ENOMEM;
goto err0;
}
dev_set_drvdata(&client->dev, priv);
input = input_allocate_device();
if (!input) {
dev_err(&client->dev, "Failed to allocate input device.\n");
error = -ENOMEM;
goto err1;
}
input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
input_set_abs_params(input, ABS_X, 95, 955, 0, 0);
input_set_abs_params(input, ABS_Y, 85, 935, 0, 0);
input->name = client->name;
input->id.bustype = BUS_I2C;
input->dev.parent = &client->dev;
input->open = migor_ts_open;
input->close = migor_ts_close;
input_set_drvdata(input, priv);
priv->client = client;
priv->input = input;
INIT_DELAYED_WORK(&priv->work, migor_ts_poscheck);
priv->irq = client->irq;
error = input_register_device(input);
if (error)
goto err1;
error = request_irq(priv->irq, migor_ts_isr, IRQF_TRIGGER_LOW,
client->name, priv);
if (error) {
dev_err(&client->dev, "Unable to request touchscreen IRQ.\n");
goto err2;
}
return 0;
err2:
input_unregister_device(input);
input = NULL; /* so we dont try to free it below */
err1:
input_free_device(input);
kfree(priv);
err0:
dev_set_drvdata(&client->dev, NULL);
return error;
}
static int migor_ts_remove(struct i2c_client *client)
{
struct migor_ts_priv *priv = dev_get_drvdata(&client->dev);
free_irq(priv->irq, priv);
input_unregister_device(priv->input);
kfree(priv);
dev_set_drvdata(&client->dev, NULL);
return 0;
}
static const struct i2c_device_id migor_ts_id[] = {
{ "migor_ts", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, migor_ts);
static struct i2c_driver migor_ts_driver = {
.driver = {
.name = "migor_ts",
},
.probe = migor_ts_probe,
.remove = migor_ts_remove,
.id_table = migor_ts_id,
};
static int __init migor_ts_init(void)
{
return i2c_add_driver(&migor_ts_driver);
}
static void __exit migor_ts_exit(void)
{
i2c_del_driver(&migor_ts_driver);
}
MODULE_DESCRIPTION("MigoR Touchscreen driver");
MODULE_AUTHOR("Magnus Damm <damm@opensource.se>");
MODULE_LICENSE("GPL");
module_init(migor_ts_init);
module_exit(migor_ts_exit);
