#include <linux/i2c.h>
#include <linux/interrupt.h>
#include <linux/input.h>
#include <linux/gpio/consumer.h>
#include <linux/delay.h>
#include <linux/input/as5011.h>
#include <linux/slab.h>
#include <linux/module.h>
#define DRIVER_DESC "Driver for Austria Microsystems AS5011 joystick"
#define MODULE_DEVICE_ALIAS "as5011"
MODULE_AUTHOR("Fabien Marteau <fabien.marteau@armadeus.com>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
#define AS5011_CTRL1 0x76
#define AS5011_CTRL2 0x75
#define AS5011_XP 0x43
#define AS5011_XN 0x44
#define AS5011_YP 0x53
#define AS5011_YN 0x54
#define AS5011_X_REG 0x41
#define AS5011_Y_REG 0x42
#define AS5011_X_RES_INT 0x51
#define AS5011_Y_RES_INT 0x52
#define AS5011_CTRL1_LP_PULSED 0x80
#define AS5011_CTRL1_LP_ACTIVE 0x40
#define AS5011_CTRL1_LP_CONTINUE 0x20
#define AS5011_CTRL1_INT_WUP_EN 0x10
#define AS5011_CTRL1_INT_ACT_EN 0x08
#define AS5011_CTRL1_EXT_CLK_EN 0x04
#define AS5011_CTRL1_SOFT_RST 0x02
#define AS5011_CTRL1_DATA_VALID 0x01
#define AS5011_CTRL2_EXT_SAMPLE_EN 0x08
#define AS5011_CTRL2_RC_BIAS_ON 0x04
#define AS5011_CTRL2_INV_SPINNING 0x02
#define AS5011_MAX_AXIS 80
#define AS5011_MIN_AXIS (-80)
#define AS5011_FUZZ 8
#define AS5011_FLAT 40
struct as5011_device {
struct input_dev *input_dev;
struct i2c_client *i2c_client;
struct gpio_desc *button_gpiod;
unsigned int button_irq;
unsigned int axis_irq;
};
static int as5011_i2c_write(struct i2c_client *client,
uint8_t aregaddr,
uint8_t avalue)
{
uint8_t data[2] = { aregaddr, avalue };
struct i2c_msg msg = {
.addr = client->addr,
.flags = I2C_M_IGNORE_NAK,
.len = 2,
.buf = (uint8_t *)data
};
int error;
error = i2c_transfer(client->adapter, &msg, 1);
return error < 0 ? error : 0;
}
static int as5011_i2c_read(struct i2c_client *client,
uint8_t aregaddr, signed char *value)
{
uint8_t data[2] = { aregaddr };
struct i2c_msg msg_set[2] = {
{
.addr = client->addr,
.flags = I2C_M_REV_DIR_ADDR,
.len = 1,
.buf = (uint8_t *)data
},
{
.addr = client->addr,
.flags = I2C_M_RD | I2C_M_NOSTART,
.len = 1,
.buf = (uint8_t *)data
}
};
int error;
error = i2c_transfer(client->adapter, msg_set, 2);
if (error < 0)
return error;
*value = data[0] & 0x80 ? -1 * (1 + ~data[0]) : data[0];
return 0;
}
static irqreturn_t as5011_button_interrupt(int irq, void *dev_id)
{
struct as5011_device *as5011 = dev_id;
int val = gpiod_get_value_cansleep(as5011->button_gpiod);
input_report_key(as5011->input_dev, BTN_JOYSTICK, !val);
input_sync(as5011->input_dev);
return IRQ_HANDLED;
}
static irqreturn_t as5011_axis_interrupt(int irq, void *dev_id)
{
struct as5011_device *as5011 = dev_id;
int error;
signed char x, y;
error = as5011_i2c_read(as5011->i2c_client, AS5011_X_RES_INT, &x);
if (error < 0)
goto out;
error = as5011_i2c_read(as5011->i2c_client, AS5011_Y_RES_INT, &y);
if (error < 0)
goto out;
input_report_abs(as5011->input_dev, ABS_X, x);
input_report_abs(as5011->input_dev, ABS_Y, y);
input_sync(as5011->input_dev);
out:
return IRQ_HANDLED;
}
static int as5011_configure_chip(struct as5011_device *as5011,
const struct as5011_platform_data *plat_dat)
{
struct i2c_client *client = as5011->i2c_client;
int error;
signed char value;
error = as5011_i2c_write(client, AS5011_CTRL1,
AS5011_CTRL1_SOFT_RST);
if (error < 0) {
dev_err(&client->dev, "Soft reset failed\n");
return error;
}
mdelay(10);
error = as5011_i2c_write(client, AS5011_CTRL1,
AS5011_CTRL1_LP_PULSED |
AS5011_CTRL1_LP_ACTIVE |
AS5011_CTRL1_INT_ACT_EN);
if (error < 0) {
dev_err(&client->dev, "Power config failed\n");
return error;
}
error = as5011_i2c_write(client, AS5011_CTRL2,
AS5011_CTRL2_INV_SPINNING);
if (error < 0) {
dev_err(&client->dev, "Can't invert spinning\n");
return error;
}
error = as5011_i2c_write(client, AS5011_XP, plat_dat->xp);
if (error < 0) {
dev_err(&client->dev, "Can't write threshold\n");
return error;
}
error = as5011_i2c_write(client, AS5011_XN, plat_dat->xn);
if (error < 0) {
dev_err(&client->dev, "Can't write threshold\n");
return error;
}
error = as5011_i2c_write(client, AS5011_YP, plat_dat->yp);
if (error < 0) {
dev_err(&client->dev, "Can't write threshold\n");
return error;
}
error = as5011_i2c_write(client, AS5011_YN, plat_dat->yn);
if (error < 0) {
dev_err(&client->dev, "Can't write threshold\n");
return error;
}
error = as5011_i2c_read(client, AS5011_X_RES_INT, &value);
if (error < 0) {
dev_err(&client->dev, "Can't read i2c X resolution value\n");
return error;
}
return 0;
}
static int as5011_probe(struct i2c_client *client)
{
const struct as5011_platform_data *plat_data;
struct as5011_device *as5011;
struct input_dev *input_dev;
int irq;
int error;
plat_data = dev_get_platdata(&client->dev);
if (!plat_data)
return -EINVAL;
if (!plat_data->axis_irq) {
dev_err(&client->dev, "No axis IRQ?\n");
return -EINVAL;
}
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_NOSTART |
I2C_FUNC_PROTOCOL_MANGLING)) {
dev_err(&client->dev,
"need i2c bus that supports protocol mangling\n");
return -ENODEV;
}
as5011 = kmalloc_obj(*as5011);
input_dev = input_allocate_device();
if (!as5011 || !input_dev) {
dev_err(&client->dev,
"Can't allocate memory for device structure\n");
error = -ENOMEM;
goto err_free_mem;
}
as5011->i2c_client = client;
as5011->input_dev = input_dev;
as5011->axis_irq = plat_data->axis_irq;
input_dev->name = "Austria Microsystem as5011 joystick";
input_dev->id.bustype = BUS_I2C;
input_dev->dev.parent = &client->dev;
input_set_capability(input_dev, EV_KEY, BTN_JOYSTICK);
input_set_abs_params(input_dev, ABS_X,
AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
input_set_abs_params(as5011->input_dev, ABS_Y,
AS5011_MIN_AXIS, AS5011_MAX_AXIS, AS5011_FUZZ, AS5011_FLAT);
as5011->button_gpiod = devm_gpiod_get(&client->dev, NULL, GPIOD_IN);
if (IS_ERR(as5011->button_gpiod)) {
error = PTR_ERR(as5011->button_gpiod);
dev_err(&client->dev, "Failed to request button GPIO\n");
goto err_free_mem;
}
gpiod_set_consumer_name(as5011->button_gpiod, "AS5011 button");
irq = gpiod_to_irq(as5011->button_gpiod);
if (irq < 0) {
dev_err(&client->dev,
"Failed to get irq number for button gpio\n");
error = irq;
goto err_free_mem;
}
as5011->button_irq = irq;
error = request_threaded_irq(as5011->button_irq,
NULL, as5011_button_interrupt,
IRQF_TRIGGER_RISING |
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
"as5011_button", as5011);
if (error < 0) {
dev_err(&client->dev,
"Can't allocate button irq %d\n", as5011->button_irq);
goto err_free_mem;
}
error = as5011_configure_chip(as5011, plat_data);
if (error)
goto err_free_button_irq;
error = request_threaded_irq(as5011->axis_irq, NULL,
as5011_axis_interrupt,
plat_data->axis_irqflags | IRQF_ONESHOT,
"as5011_joystick", as5011);
if (error) {
dev_err(&client->dev,
"Can't allocate axis irq %d\n", plat_data->axis_irq);
goto err_free_button_irq;
}
error = input_register_device(as5011->input_dev);
if (error) {
dev_err(&client->dev, "Failed to register input device\n");
goto err_free_axis_irq;
}
i2c_set_clientdata(client, as5011);
return 0;
err_free_axis_irq:
free_irq(as5011->axis_irq, as5011);
err_free_button_irq:
free_irq(as5011->button_irq, as5011);
err_free_mem:
input_free_device(input_dev);
kfree(as5011);
return error;
}
static void as5011_remove(struct i2c_client *client)
{
struct as5011_device *as5011 = i2c_get_clientdata(client);
free_irq(as5011->axis_irq, as5011);
free_irq(as5011->button_irq, as5011);
input_unregister_device(as5011->input_dev);
kfree(as5011);
}
static const struct i2c_device_id as5011_id[] = {
{ MODULE_DEVICE_ALIAS },
{ }
};
MODULE_DEVICE_TABLE(i2c, as5011_id);
static struct i2c_driver as5011_driver = {
.driver = {
.name = "as5011",
},
.probe = as5011_probe,
.remove = as5011_remove,
.id_table = as5011_id,
};
module_i2c_driver(as5011_driver);
