linux-stable/drivers/input/touchscreen/egalax_ts.c
Javier Martinez Canillas 02d9bd05dc Input: touchscreen - export OF module alias information
The I2C core always reports the MODALIAS uevent as "i2c:<client name"
regardless if the driver was matched using the I2C id_table or the
of_match_table. So technically there's no need for a driver to export
the OF table since currently it's not used.

In fact, the I2C device ID table is mandatory for I2C drivers since
a i2c_device_id is passed to the driver's probe function even if the
I2C core used the OF table to match the driver.

And since the I2C core uses different tables, OF-only drivers needs to
have duplicated data that has to be kept in sync and also the dev node
compatible manufacturer prefix is stripped when reporting the MODALIAS.

To avoid the above, the I2C core behavior may be changed in the future
to not require an I2C device table for OF-only drivers and report the
OF module alias. So, it's better to also export the OF table to prevent
breaking module autoloading if that happens.

Signed-off-by: Javier Martinez Canillas <javier@osg.samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2015-07-30 11:05:37 -07:00

283 lines
6.9 KiB
C

/*
* 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/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>
#include <linux/of_gpio.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)
{
struct device_node *np = client->dev.of_node;
int gpio;
int ret;
if (!np)
return -ENODEV;
gpio = of_get_named_gpio(np, "wakeup-gpios", 0);
if (!gpio_is_valid(gpio))
return -ENODEV;
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 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 egalax_ts_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct egalax_ts *ts;
struct input_dev *input_dev;
int error;
ts = devm_kzalloc(&client->dev, sizeof(struct egalax_ts), GFP_KERNEL);
if (!ts) {
dev_err(&client->dev, "Failed to allocate memory\n");
return -ENOMEM;
}
input_dev = devm_input_allocate_device(&client->dev);
if (!input_dev) {
dev_err(&client->dev, "Failed to allocate memory\n");
return -ENOMEM;
}
ts->client = client;
ts->input_dev = input_dev;
/* controller may be in sleep, wake it up. */
error = egalax_wake_up_device(client);
if (error) {
dev_err(&client->dev, "Failed to wake up the controller\n");
return error;
}
error = egalax_firmware_version(client);
if (error < 0) {
dev_err(&client->dev, "Failed to read firmware version\n");
return error;
}
input_dev->name = "EETI eGalax Touch Screen";
input_dev->id.bustype = BUS_I2C;
__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_Y, 0, EGALAX_MAX_Y, 0, 0);
input_mt_init_slots(input_dev, MAX_SUPPORT_POINTS, 0);
input_set_drvdata(input_dev, ts);
error = devm_request_threaded_irq(&client->dev, 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");
return error;
}
error = input_register_device(ts->input_dev);
if (error)
return error;
i2c_set_clientdata(client, ts);
return 0;
}
static const struct i2c_device_id egalax_ts_id[] = {
{ "egalax_ts", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, egalax_ts_id);
static int __maybe_unused 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 __maybe_unused egalax_ts_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
return egalax_wake_up_device(client);
}
static SIMPLE_DEV_PM_OPS(egalax_ts_pm_ops, egalax_ts_suspend, egalax_ts_resume);
static const struct of_device_id egalax_ts_dt_ids[] = {
{ .compatible = "eeti,egalax_ts" },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, egalax_ts_dt_ids);
static struct i2c_driver egalax_ts_driver = {
.driver = {
.name = "egalax_ts",
.pm = &egalax_ts_pm_ops,
.of_match_table = egalax_ts_dt_ids,
},
.id_table = egalax_ts_id,
.probe = egalax_ts_probe,
};
module_i2c_driver(egalax_ts_driver);
MODULE_AUTHOR("Freescale Semiconductor, Inc.");
MODULE_DESCRIPTION("Touchscreen driver for EETI eGalax touch controller");
MODULE_LICENSE("GPL");