337 lines
8.1 KiB
C
Executable File
337 lines
8.1 KiB
C
Executable File
/*
|
|
* Driver for ELAN eKTF2127 i2c touchscreen controller
|
|
*
|
|
* For this driver the layout of the Chipone icn8318 i2c
|
|
* touchscreencontroller is used.
|
|
*
|
|
* This program 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.
|
|
*
|
|
* Author:
|
|
* Michel Verlaan <michel.verl@gmail.com>
|
|
* Siebren Vroegindeweij <siebren.vroegindeweij@hotmail.com>
|
|
*
|
|
* Original chipone_icn8318 driver:
|
|
* Hans de Goede <hdegoede@redhat.com>
|
|
*/
|
|
|
|
#include <linux/gpio/consumer.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/input.h>
|
|
#include <linux/input/mt.h>
|
|
#include <linux/input/touchscreen.h>
|
|
#include <linux/module.h>
|
|
#include <linux/of.h>
|
|
#include <linux/delay.h>
|
|
|
|
/* Packet header defines (first byte of data send / received) */
|
|
#define EKTF2127_NOISE 0x40
|
|
#define EKTF2127_RESPONSE 0x52
|
|
#define EKTF2127_REQUEST 0x53
|
|
#define EKTF2127_HELLO 0x55
|
|
#define EKTF2127_REPORT 0x5d
|
|
#define EKTF2127_CALIB_DONE 0x66
|
|
|
|
/* Register defines (second byte of data send / received) */
|
|
#define EKTF2127_ENV_NOISY 0x41
|
|
#define EKTF2127_HEIGHT 0x60
|
|
#define EKTF2127_WIDTH 0x63
|
|
|
|
/* 2 bytes header + 5 * 3 bytes coordinates + 3 bytes pressure info + footer */
|
|
#define EKTF2127_TOUCH_REPORT_SIZE 21
|
|
#define EKTF2127_MAX_TOUCHES 5
|
|
|
|
struct ektf2127_ts {
|
|
struct i2c_client *client;
|
|
struct input_dev *input;
|
|
struct gpio_desc *power_gpios;
|
|
struct touchscreen_properties prop;
|
|
};
|
|
|
|
static void ektf2127_parse_coordinates(const u8* buf, unsigned int touch_count,
|
|
struct input_mt_pos *touches)
|
|
{
|
|
int index = 0;
|
|
int i;
|
|
|
|
for (i = 0; i < touch_count; i++) {
|
|
index = 2 + i * 3;
|
|
|
|
touches[i].x = (buf[index] & 0x0f);
|
|
touches[i].x <<= 8;
|
|
touches[i].x |= buf[index + 2];
|
|
|
|
touches[i].y = (buf[index] & 0xf0);
|
|
touches[i].y <<= 4;
|
|
touches[i].y |= buf[index + 1];
|
|
}
|
|
}
|
|
|
|
static void ektf2127_report_event(struct ektf2127_ts *ts, const u8 *buf)
|
|
{
|
|
struct input_mt_pos touches[EKTF2127_MAX_TOUCHES];
|
|
int slots[EKTF2127_MAX_TOUCHES];
|
|
unsigned int touch_count, i;
|
|
|
|
touch_count = buf[1] & 0x07;
|
|
if (touch_count > EKTF2127_MAX_TOUCHES) {
|
|
dev_err(&ts->client->dev,
|
|
"Too many touches %d > %d\n",
|
|
touch_count, EKTF2127_MAX_TOUCHES);
|
|
touch_count = EKTF2127_MAX_TOUCHES;
|
|
}
|
|
|
|
ektf2127_parse_coordinates(buf, touch_count, touches);
|
|
input_mt_assign_slots(ts->input, slots, touches,
|
|
touch_count, 0);
|
|
|
|
for (i = 0; i < touch_count; i++) {
|
|
input_mt_slot(ts->input, slots[i]);
|
|
input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, true);
|
|
touchscreen_report_pos(ts->input, &ts->prop,
|
|
touches[i].x, touches[i].y, true);
|
|
}
|
|
|
|
input_mt_sync_frame(ts->input);
|
|
input_sync(ts->input);
|
|
}
|
|
|
|
static irqreturn_t ektf2127_irq(int irq, void *dev_id)
|
|
{
|
|
struct ektf2127_ts *ts = dev_id;
|
|
struct device *dev = &ts->client->dev;
|
|
char buf[EKTF2127_TOUCH_REPORT_SIZE];
|
|
int ret;
|
|
|
|
ret = i2c_master_recv(ts->client, buf, EKTF2127_TOUCH_REPORT_SIZE);
|
|
if (ret != EKTF2127_TOUCH_REPORT_SIZE) {
|
|
dev_err(dev, "Error reading touch data: %d\n", ret);
|
|
goto out;
|
|
}
|
|
|
|
switch (buf[0]) {
|
|
case EKTF2127_REPORT:
|
|
ektf2127_report_event(ts, buf);
|
|
break;
|
|
|
|
case EKTF2127_NOISE:
|
|
if (buf[1] == EKTF2127_ENV_NOISY)
|
|
dev_dbg(dev, "Environment is electrically noisy\n");
|
|
break;
|
|
|
|
case EKTF2127_HELLO:
|
|
case EKTF2127_CALIB_DONE:
|
|
break;
|
|
|
|
default:
|
|
dev_err(dev, "Unexpected packet header byte %#02x\n", buf[0]);
|
|
break;
|
|
}
|
|
|
|
out:
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int ektf2127_start(struct input_dev *dev)
|
|
{
|
|
struct ektf2127_ts *ts = input_get_drvdata(dev);
|
|
|
|
enable_irq(ts->client->irq);
|
|
gpiod_set_value_cansleep(ts->power_gpios, 1);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ektf2127_stop(struct input_dev *dev)
|
|
{
|
|
struct ektf2127_ts *ts = input_get_drvdata(dev);
|
|
|
|
disable_irq(ts->client->irq);
|
|
gpiod_set_value_cansleep(ts->power_gpios, 0);
|
|
}
|
|
|
|
static int __maybe_unused ektf2127_suspend(struct device *dev)
|
|
{
|
|
struct ektf2127_ts *ts = i2c_get_clientdata(to_i2c_client(dev));
|
|
|
|
mutex_lock(&ts->input->mutex);
|
|
if (ts->input->users)
|
|
ektf2127_stop(ts->input);
|
|
mutex_unlock(&ts->input->mutex);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int __maybe_unused ektf2127_resume(struct device *dev)
|
|
{
|
|
struct ektf2127_ts *ts = i2c_get_clientdata(to_i2c_client(dev));
|
|
|
|
mutex_lock(&ts->input->mutex);
|
|
if (ts->input->users)
|
|
ektf2127_start(ts->input);
|
|
mutex_unlock(&ts->input->mutex);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static SIMPLE_DEV_PM_OPS(ektf2127_pm_ops, ektf2127_suspend,
|
|
ektf2127_resume);
|
|
|
|
static int ektf2127_query_dimension(struct i2c_client *client, bool width)
|
|
{
|
|
struct device *dev = &client->dev;
|
|
const char *what = width ? "width" : "height";
|
|
u8 what_code = width ? EKTF2127_WIDTH : EKTF2127_HEIGHT;
|
|
u8 buf[4];
|
|
int ret;
|
|
int error;
|
|
|
|
/* Request dimension */
|
|
buf[0] = EKTF2127_REQUEST;
|
|
buf[1] = width ? EKTF2127_WIDTH : EKTF2127_HEIGHT;
|
|
buf[2] = 0x00;
|
|
buf[3] = 0x00;
|
|
ret = i2c_master_send(client, buf, sizeof(buf));
|
|
if (ret != sizeof(buf)) {
|
|
error = ret < 0 ? ret : -EIO;
|
|
dev_err(dev, "Failed to request %s: %d\n", what, error);
|
|
return error;
|
|
}
|
|
|
|
msleep(20);
|
|
|
|
/* Read response */
|
|
ret = i2c_master_recv(client, buf, sizeof(buf));
|
|
if (ret != sizeof(buf)) {
|
|
error = ret < 0 ? ret : -EIO;
|
|
dev_err(dev, "Failed to receive %s data: %d\n", what, error);
|
|
return error;
|
|
}
|
|
|
|
if (buf[0] != EKTF2127_RESPONSE || buf[1] != what_code) {
|
|
dev_err(dev, "Unexpected %s data: %#02x %#02x\n",
|
|
what, buf[0], buf[1]);
|
|
return -EIO;
|
|
}
|
|
|
|
return (((buf[3] & 0xf0) << 4) | buf[2]) - 1;
|
|
}
|
|
|
|
static int ektf2127_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct device *dev = &client->dev;
|
|
struct ektf2127_ts *ts;
|
|
struct input_dev *input;
|
|
u8 buf[4];
|
|
int max_x, max_y;
|
|
int error;
|
|
|
|
if (!client->irq) {
|
|
dev_err(dev, "Error no irq specified\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
|
|
if (!ts)
|
|
return -ENOMEM;
|
|
|
|
/* This requests the gpio *and* turns on the touchscreen controller */
|
|
ts->power_gpios = devm_gpiod_get(dev, "power", GPIOD_OUT_HIGH);
|
|
if (IS_ERR(ts->power_gpios)) {
|
|
error = PTR_ERR(ts->power_gpios);
|
|
if (error != -EPROBE_DEFER)
|
|
dev_err(dev, "Error getting power gpio: %d\n", error);
|
|
return error;
|
|
}
|
|
|
|
input = devm_input_allocate_device(dev);
|
|
if (!input)
|
|
return -ENOMEM;
|
|
|
|
input->name = client->name;
|
|
input->id.bustype = BUS_I2C;
|
|
input->open = ektf2127_start;
|
|
input->close = ektf2127_stop;
|
|
|
|
ts->client = client;
|
|
|
|
/* Read hello (ignore result, depends on initial power state) */
|
|
msleep(20);
|
|
i2c_master_recv(ts->client, buf, sizeof(buf));
|
|
|
|
/* Read resolution from chip */
|
|
max_x = ektf2127_query_dimension(client, true);
|
|
if (max_x < 0)
|
|
return max_x;
|
|
|
|
max_y = ektf2127_query_dimension(client, false);
|
|
if (max_y < 0)
|
|
return max_y;
|
|
|
|
input_set_abs_params(input, ABS_MT_POSITION_X, 0, max_x, 0, 0);
|
|
input_set_abs_params(input, ABS_MT_POSITION_Y, 0, max_y, 0, 0);
|
|
touchscreen_parse_properties(input, true, &ts->prop);
|
|
|
|
error = input_mt_init_slots(input, EKTF2127_MAX_TOUCHES,
|
|
INPUT_MT_DIRECT |
|
|
INPUT_MT_DROP_UNUSED |
|
|
INPUT_MT_TRACK);
|
|
if (error)
|
|
return error;
|
|
|
|
ts->input = input;
|
|
input_set_drvdata(input, ts);
|
|
|
|
error = devm_request_threaded_irq(dev, client->irq,
|
|
NULL, ektf2127_irq,
|
|
IRQF_ONESHOT, client->name, ts);
|
|
if (error) {
|
|
dev_err(dev, "Error requesting irq: %d\n", error);
|
|
return error;
|
|
}
|
|
|
|
/* Stop device till opened */
|
|
ektf2127_stop(ts->input);
|
|
|
|
error = input_register_device(input);
|
|
if (error)
|
|
return error;
|
|
|
|
i2c_set_clientdata(client, ts);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_OF
|
|
static const struct of_device_id ektf2127_of_match[] = {
|
|
{ .compatible = "elan,ektf2127" },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, ektf2127_of_match);
|
|
#endif
|
|
|
|
static const struct i2c_device_id ektf2127_i2c_id[] = {
|
|
{ "ektf2127", 0 },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(i2c, ektf2127_i2c_id);
|
|
|
|
static struct i2c_driver ektf2127_driver = {
|
|
.driver = {
|
|
.name = "elan_ektf2127",
|
|
.pm = &ektf2127_pm_ops,
|
|
.of_match_table = of_match_ptr(ektf2127_of_match),
|
|
},
|
|
.probe = ektf2127_probe,
|
|
.id_table = ektf2127_i2c_id,
|
|
};
|
|
module_i2c_driver(ektf2127_driver);
|
|
|
|
MODULE_DESCRIPTION("ELAN eKTF2127 I2C Touchscreen Driver");
|
|
MODULE_AUTHOR("Michel Verlaan, Siebren Vroegindeweij");
|
|
MODULE_LICENSE("GPL");
|