/*
* Wacom Penabled Driver for I2C
*/
#include <linux/module.h>
#include <linux/input.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/gpio.h>
#include <asm/unaligned.h>
#define WACOM_CMD_QUERY0 0x04
#define WACOM_CMD_QUERY1 0x00
#define WACOM_CMD_QUERY2 0x33
#define WACOM_CMD_QUERY3 0x02
#define WACOM_CMD_THROW0 0x05
#define WACOM_CMD_THROW1 0x00
#define WACOM_QUERY_SIZE 19
struct wacom_features {
int x_max;
int y_max;
int pressure_max;
char fw_version;
};
struct wacom_i2c {
struct i2c_client *client;
struct input_dev *input;
u8 data[WACOM_QUERY_SIZE];
bool prox;
int tool;
};
static int wacom_query_device(struct i2c_client *client,
struct wacom_features *features)
{
int ret;
u8 cmd1[] = { WACOM_CMD_QUERY0, WACOM_CMD_QUERY1,
WACOM_CMD_QUERY2, WACOM_CMD_QUERY3 };
u8 cmd2[] = { WACOM_CMD_THROW0, WACOM_CMD_THROW1 };
u8 data[WACOM_QUERY_SIZE];
struct i2c_msg msgs[] = {
{
.addr = client->addr,
.flags = 0,
.len = sizeof(cmd1),
.buf = cmd1,
},
{
.addr = client->addr,
.flags = 0,
.len = sizeof(cmd2),
.buf = cmd2,
},
{
.addr = client->addr,
.flags = I2C_M_RD,
.len = sizeof(data),
.buf = data,
},
};
ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
if (ret < 0)
return ret;
if (ret != ARRAY_SIZE(msgs))
return -EIO;
features->x_max = get_unaligned_le16(&data[3]);
features->y_max = get_unaligned_le16(&data[5]);
features->pressure_max = get_unaligned_le16(&data[11]);
features->fw_version = get_unaligned_le16(&data[13]);
dev_dbg(&client->dev,
"x_max:%d, y_max:%d, pressure:%d, fw:%d\n",
features->x_max, features->y_max,
features->pressure_max, features->fw_version);
return 0;
}
static irqreturn_t wacom_i2c_irq(int irq, void *dev_id)
{
struct wacom_i2c *wac_i2c = dev_id;
struct input_dev *input = wac_i2c->input;
u8 *data = wac_i2c->data;
unsigned int x, y, pressure;
unsigned char tsw, f1, f2, ers;
int error;
error = i2c_master_recv(wac_i2c->client,
wac_i2c->data, sizeof(wac_i2c->data));
if (error < 0)
goto out;
tsw = data[3] & 0x01;
ers = data[3] & 0x04;
f1 = data[3] & 0x02;
f2 = data[3] & 0x10;
x = le16_to_cpup((__le16 *)&data[4]);
y = le16_to_cpup((__le16 *)&data[6]);
pressure = le16_to_cpup((__le16 *)&data[8]);
if (!wac_i2c->prox)
wac_i2c->tool = (data[3] & 0x0c) ?
BTN_TOOL_RUBBER : BTN_TOOL_PEN;
wac_i2c->prox = data[3] & 0x20;
input_report_key(input, BTN_TOUCH, tsw || ers);
input_report_key(input, wac_i2c->tool, wac_i2c->prox);
input_report_key(input, BTN_STYLUS, f1);
input_report_key(input, BTN_STYLUS2, f2);
input_report_abs(input, ABS_X, x);
input_report_abs(input, ABS_Y, y);
input_report_abs(input, ABS_PRESSURE, pressure);
input_sync(input);
out:
return IRQ_HANDLED;
}
static int wacom_i2c_open(struct input_dev *dev)
{
struct wacom_i2c *wac_i2c = input_get_drvdata(dev);
struct i2c_client *client = wac_i2c->client;
enable_irq(client->irq);
return 0;
}
static void wacom_i2c_close(struct input_dev *dev)
{
struct wacom_i2c *wac_i2c = input_get_drvdata(dev);
struct i2c_client *client = wac_i2c->client;
disable_irq(client->irq);
}
static int wacom_i2c_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct wacom_i2c *wac_i2c;
struct input_dev *input;
struct wacom_features features = { 0 };
int error;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
dev_err(&client->dev, "i2c_check_functionality error\n");
return -EIO;
}
error = wacom_query_device(client, &features);
if (error)
return error;
wac_i2c = kzalloc(sizeof(*wac_i2c), GFP_KERNEL);
input = input_allocate_device();
if (!wac_i2c || !input) {
error = -ENOMEM;
goto err_free_mem;
}
wac_i2c->client = client;
wac_i2c->input = input;
input->name = "Wacom I2C Digitizer";
input->id.bustype = BUS_I2C;
input->id.vendor = 0x56a;
input->id.version = features.fw_version;
input->dev.parent = &client->dev;
input->open = wacom_i2c_open;
input->close = wacom_i2c_close;
input->evbit[0] |= BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
__set_bit(BTN_TOOL_PEN, input->keybit);
__set_bit(BTN_TOOL_RUBBER, input->keybit);
__set_bit(BTN_STYLUS, input->keybit);
__set_bit(BTN_STYLUS2, input->keybit);
__set_bit(BTN_TOUCH, input->keybit);
input_set_abs_params(input, ABS_X, 0, features.x_max, 0, 0);
input_set_abs_params(input, ABS_Y, 0, features.y_max, 0, 0);
input_set_abs_params(input, ABS_PRESSURE,
0, features.pressure_max, 0, 0);
input_set_drvdata(input, wac_i2c);
error = request_threaded_irq(client->irq, NULL, wacom_i2c_irq,
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
"wacom_i2c", wac_i2c);
if (error) {
dev_err(&client->dev,
"Failed to enable IRQ, error: %d\n", error);
goto err_free_mem;
}
/* Disable the IRQ, we'll enable it in wac_i2c_open() */
disable_irq(client->irq);
error = input_register_device(wac_i2c->input);
if (error) {
dev_err(&client->dev,
"Failed to register input device, error: %d\n", error);
goto err_free_irq;
}
i2c_set_clientdata(client, wac_i2c);
return 0;
err_free_irq:
free_irq(client->irq, wac_i2c);
err_free_mem:
input_free_device(input);
kfree(wac_i2c);
return error;
}
static int wacom_i2c_remove(struct i2c_client *client)
{
struct wacom_i2c *wac_i2c = i2c_get_clientdata(client);
free_irq(client->irq, wac_i2c);
input_unregister_device(wac_i2c->input);
kfree(wac_i2c);
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int wacom_i2c_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
disable_irq(client->irq);
return 0;
}
static int wacom_i2c_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
enable_irq(client->irq);
return 0;
}
#endif
static SIMPLE_DEV_PM_OPS(wacom_i2c_pm, wacom_i2c_suspend, wacom_i2c_resume);
static const struct i2c_device_id wacom_i2c_id[] = {
{ "WAC_I2C_EMR", 0 },
{ },
};
MODULE_DEVICE_TABLE(i2c, wacom_i2c_id);
static struct i2c_driver wacom_i2c_driver = {
.driver = {
.name = "wacom_i2c",
.owner = THIS_MODULE,
.pm = &wacom_i2c_pm,
},
.probe = wacom_i2c_probe,
.remove = wacom_i2c_remove,
.id_table = wacom_i2c_id,
};
module_i2c_driver(wacom_i2c_driver);
MODULE_AUTHOR("Tatsunosuke Tobita <tobita.tatsunosuke@wacom.co.jp>");
MODULE_DESCRIPTION("WACOM EMR I2C Driver");
MODULE_LICENSE("GPL");
