linux_dsm_epyc7002/drivers/input/touchscreen/ar1021_i2c.c
Christian Gmeiner dd4cae8bf1 Input: Add Microchip AR1021 i2c touchscreen
This patch adds support for the ar1021 i2c based touchscreen.
The driver is quite simple and only supports the Touch
Reporting Protocol.

This is the final version for an RFC patch send a while ago.
http://www.spinics.net/lists/linux-input/msg29419.html

Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2014-10-09 15:27:42 -07:00

182 lines
4.1 KiB
C

/*
* Microchip AR1021 driver for I2C
*
* Author: Christian Gmeiner <christian.gmeiner@gmail.com>
*
* License: GPLv2 as published by the FSF.
*/
#include <linux/module.h>
#include <linux/input.h>
#include <linux/of.h>
#include <linux/i2c.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#define AR1021_TOCUH_PKG_SIZE 5
#define AR1021_MAX_X 4095
#define AR1021_MAX_Y 4095
struct ar1021_i2c {
struct i2c_client *client;
struct input_dev *input;
u8 data[AR1021_TOCUH_PKG_SIZE];
};
static irqreturn_t ar1021_i2c_irq(int irq, void *dev_id)
{
struct ar1021_i2c *ar1021 = dev_id;
struct input_dev *input = ar1021->input;
u8 *data = ar1021->data;
unsigned int x, y, button;
int retval;
retval = i2c_master_recv(ar1021->client,
ar1021->data, sizeof(ar1021->data));
if (retval != sizeof(ar1021->data))
goto out;
/* sync bit set ? */
if ((data[0] & 0x80) == 0)
goto out;
button = data[0] & BIT(0);
x = ((data[2] & 0x1f) << 7) | (data[1] & 0x7f);
y = ((data[4] & 0x1f) << 7) | (data[3] & 0x7f);
input_report_abs(input, ABS_X, x);
input_report_abs(input, ABS_Y, y);
input_report_key(input, BTN_TOUCH, button);
input_sync(input);
out:
return IRQ_HANDLED;
}
static int ar1021_i2c_open(struct input_dev *dev)
{
struct ar1021_i2c *ar1021 = input_get_drvdata(dev);
struct i2c_client *client = ar1021->client;
enable_irq(client->irq);
return 0;
}
static void ar1021_i2c_close(struct input_dev *dev)
{
struct ar1021_i2c *ar1021 = input_get_drvdata(dev);
struct i2c_client *client = ar1021->client;
disable_irq(client->irq);
}
static int ar1021_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct ar1021_i2c *ar1021;
struct input_dev *input;
int error;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
dev_err(&client->dev, "i2c_check_functionality error\n");
return -ENXIO;
}
ar1021 = devm_kzalloc(&client->dev, sizeof(*ar1021), GFP_KERNEL);
if (!ar1021)
return -ENOMEM;
input = devm_input_allocate_device(&client->dev);
if (!input)
return -ENOMEM;
ar1021->client = client;
ar1021->input = input;
input->name = "ar1021 I2C Touchscreen";
input->id.bustype = BUS_I2C;
input->dev.parent = &client->dev;
input->open = ar1021_i2c_open;
input->close = ar1021_i2c_close;
input_set_capability(input, EV_KEY, BTN_TOUCH);
input_set_abs_params(input, ABS_X, 0, AR1021_MAX_X, 0, 0);
input_set_abs_params(input, ABS_Y, 0, AR1021_MAX_Y, 0, 0);
input_set_drvdata(input, ar1021);
error = devm_request_threaded_irq(&client->dev, client->irq,
NULL, ar1021_i2c_irq,
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
"ar1021_i2c", ar1021);
if (error) {
dev_err(&client->dev,
"Failed to enable IRQ, error: %d\n", error);
return error;
}
/* Disable the IRQ, we'll enable it in ar1021_i2c_open() */
disable_irq(client->irq);
error = input_register_device(ar1021->input);
if (error) {
dev_err(&client->dev,
"Failed to register input device, error: %d\n", error);
return error;
}
i2c_set_clientdata(client, ar1021);
return 0;
}
static int __maybe_unused ar1021_i2c_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
disable_irq(client->irq);
return 0;
}
static int __maybe_unused ar1021_i2c_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
enable_irq(client->irq);
return 0;
}
static SIMPLE_DEV_PM_OPS(ar1021_i2c_pm, ar1021_i2c_suspend, ar1021_i2c_resume);
static const struct i2c_device_id ar1021_i2c_id[] = {
{ "MICROCHIP_AR1021_I2C", 0 },
{ },
};
MODULE_DEVICE_TABLE(i2c, ar1021_i2c_id);
static struct of_device_id ar1021_i2c_of_match[] = {
{ .compatible = "microchip,ar1021-i2c", },
{ }
};
MODULE_DEVICE_TABLE(of, ar1021_i2c_of_match);
static struct i2c_driver ar1021_i2c_driver = {
.driver = {
.name = "ar1021_i2c",
.owner = THIS_MODULE,
.pm = &ar1021_i2c_pm,
.of_match_table = ar1021_i2c_of_match,
},
.probe = ar1021_i2c_probe,
.id_table = ar1021_i2c_id,
};
module_i2c_driver(ar1021_i2c_driver);
MODULE_AUTHOR("Christian Gmeiner <christian.gmeiner@gmail.com>");
MODULE_DESCRIPTION("Microchip AR1021 I2C Driver");
MODULE_LICENSE("GPL");