// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2011 Kionix, Inc.
* Written by Chris Hudson <[email protected]>
*/
#include <linux/delay.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/input/kxtj9.h>
#define NAME "kxtj9"
#define G_MAX 8000
/* OUTPUT REGISTERS */
#define XOUT_L 0x06
#define WHO_AM_I 0x0F
/* CONTROL REGISTERS */
#define INT_REL 0x1A
#define CTRL_REG1 0x1B
#define INT_CTRL1 0x1E
#define DATA_CTRL 0x21
/* CONTROL REGISTER 1 BITS */
#define PC1_OFF 0x7F
#define PC1_ON (1 << 7)
/* Data ready funtion enable bit: set during probe if using irq mode */
#define DRDYE (1 << 5)
/* DATA CONTROL REGISTER BITS */
#define ODR12_5F 0
#define ODR25F 1
#define ODR50F 2
#define ODR100F 3
#define ODR200F 4
#define ODR400F 5
#define ODR800F 6
/* INTERRUPT CONTROL REGISTER 1 BITS */
/* Set these during probe if using irq mode */
#define KXTJ9_IEL (1 << 3)
#define KXTJ9_IEA (1 << 4)
#define KXTJ9_IEN (1 << 5)
/* INPUT_ABS CONSTANTS */
#define FUZZ 3
#define FLAT 3
/* RESUME STATE INDICES */
#define RES_DATA_CTRL 0
#define RES_CTRL_REG1 1
#define RES_INT_CTRL1 2
#define RESUME_ENTRIES 3
/*
* The following table lists the maximum appropriate poll interval for each
* available output data rate.
*/
static const struct {
unsigned int cutoff;
u8 mask;
} kxtj9_odr_table[] = {
{ 3, ODR800F },
{ 5, ODR400F },
{ 10, ODR200F },
{ 20, ODR100F },
{ 40, ODR50F },
{ 80, ODR25F },
{ 0, ODR12_5F},
};
struct kxtj9_data {
struct i2c_client *client;
struct kxtj9_platform_data pdata;
struct input_dev *input_dev;
unsigned int last_poll_interval;
u8 shift;
u8 ctrl_reg1;
u8 data_ctrl;
u8 int_ctrl;
};
static int kxtj9_i2c_read(struct kxtj9_data *tj9, u8 addr, u8 *data, int len)
{
struct i2c_msg msgs[] = {
{
.addr = tj9->client->addr,
.flags = tj9->client->flags,
.len = 1,
.buf = &addr,
},
{
.addr = tj9->client->addr,
.flags = tj9->client->flags | I2C_M_RD,
.len = len,
.buf = data,
},
};
return i2c_transfer(tj9->client->adapter, msgs, 2);
}
static void kxtj9_report_acceleration_data(struct kxtj9_data *tj9)
{
s16 acc_data[3]; /* Data bytes from hardware xL, xH, yL, yH, zL, zH */
s16 x, y, z;
int err;
err = kxtj9_i2c_read(tj9, XOUT_L, (u8 *)acc_data, 6);
if (err < 0)
dev_err(&tj9->client->dev, "accelerometer data read failed\n");
x = le16_to_cpu(acc_data[tj9->pdata.axis_map_x]);
y = le16_to_cpu(acc_data[tj9->pdata.axis_map_y]);
z = le16_to_cpu(acc_data[tj9->pdata.axis_map_z]);
x >>= tj9->shift;
y >>= tj9->shift;
z >>= tj9->shift;
input_report_abs(tj9->input_dev, ABS_X, tj9->pdata.negate_x ? -x : x);
input_report_abs(tj9->input_dev, ABS_Y, tj9->pdata.negate_y ? -y : y);
input_report_abs(tj9->input_dev, ABS_Z, tj9->pdata.negate_z ? -z : z);
input_sync(tj9->input_dev);
}
static irqreturn_t kxtj9_isr(int irq, void *dev)
{
struct kxtj9_data *tj9 = dev;
int err;
/* data ready is the only possible interrupt type */
kxtj9_report_acceleration_data(tj9);
err = i2c_smbus_read_byte_data(tj9->client, INT_REL);
if (err < 0)
dev_err(&tj9->client->dev,
"error clearing interrupt status: %d\n", err);
return IRQ_HANDLED;
}
static int kxtj9_update_g_range(struct kxtj9_data *tj9, u8 new_g_range)
{
switch (new_g_range) {
case KXTJ9_G_2G:
tj9->shift = 4;
break;
case KXTJ9_G_4G:
tj9->shift = 3;
break;
case KXTJ9_G_8G:
tj9->shift = 2;
break;
default:
return -EINVAL;
}
tj9->ctrl_reg1 &= 0xe7;
tj9->ctrl_reg1 |= new_g_range;
return 0;
}
static int kxtj9_update_odr(struct kxtj9_data *tj9, unsigned int poll_interval)
{
int err;
int i;
/* Use the lowest ODR that can support the requested poll interval */
for (i = 0; i < ARRAY_SIZE(kxtj9_odr_table); i++) {
tj9->data_ctrl = kxtj9_odr_table[i].mask;
if (poll_interval < kxtj9_odr_table[i].cutoff)
break;
}
err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0);
if (err < 0)
return err;
err = i2c_smbus_write_byte_data(tj9->client, DATA_CTRL, tj9->data_ctrl);
if (err < 0)
return err;
err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
if (err < 0)
return err;
return 0;
}
static int kxtj9_device_power_on(struct kxtj9_data *tj9)
{
if (tj9->pdata.power_on)
return tj9->pdata.power_on();
return 0;
}
static void kxtj9_device_power_off(struct kxtj9_data *tj9)
{
int err;
tj9->ctrl_reg1 &= PC1_OFF;
err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
if (err < 0)
dev_err(&tj9->client->dev, "soft power off failed\n");
if (tj9->pdata.power_off)
tj9->pdata.power_off();
}
static int kxtj9_enable(struct kxtj9_data *tj9)
{
int err;
err = kxtj9_device_power_on(tj9);
if (err < 0)
return err;
/* ensure that PC1 is cleared before updating control registers */
err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, 0);
if (err < 0)
return err;
/* only write INT_CTRL_REG1 if in irq mode */
if (tj9->client->irq) {
err = i2c_smbus_write_byte_data(tj9->client,
INT_CTRL1, tj9->int_ctrl);
if (err < 0)
return err;
}
err = kxtj9_update_g_range(tj9, tj9->pdata.g_range);
if (err < 0)
return err;
/* turn on outputs */
tj9->ctrl_reg1 |= PC1_ON;
err = i2c_smbus_write_byte_data(tj9->client, CTRL_REG1, tj9->ctrl_reg1);
if (err < 0)
return err;
err = kxtj9_update_odr(tj9, tj9->last_poll_interval);
if (err < 0)
return err;
/* clear initial interrupt if in irq mode */
if (tj9->client->irq) {
err = i2c_smbus_read_byte_data(tj9->client, INT_REL);
if (err < 0) {
dev_err(&tj9->client->dev,
"error clearing interrupt: %d\n", err);
goto fail;
}
}
return 0;
fail:
kxtj9_device_power_off(tj9);
return err;
}
static void kxtj9_disable(struct kxtj9_data *tj9)
{
kxtj9_device_power_off(tj9);
}
static int kxtj9_input_open(struct input_dev *input)
{
struct kxtj9_data *tj9 = input_get_drvdata(input);
return kxtj9_enable(tj9);
}
static void kxtj9_input_close(struct input_dev *dev)
{
struct kxtj9_data *tj9 = input_get_drvdata(dev);
kxtj9_disable(tj9);
}
/*
* When IRQ mode is selected, we need to provide an interface to allow the user
* to change the output data rate of the part. For consistency, we are using
* the set_poll method, which accepts a poll interval in milliseconds, and then
* calls update_odr() while passing this value as an argument. In IRQ mode, the
* data outputs will not be read AT the requested poll interval, rather, the
* lowest ODR that can support the requested interval. The client application
* will be responsible for retrieving data from the input node at the desired
* interval.
*/
/* Returns currently selected poll interval (in ms) */
static ssize_t kxtj9_get_poll(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct kxtj9_data *tj9 = i2c_get_clientdata(client);
return sprintf(buf, "%d\n", tj9->last_poll_interval);
}
/* Allow users to select a new poll interval (in ms) */
static ssize_t kxtj9_set_poll(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct kxtj9_data *tj9 = i2c_get_clientdata(client);
struct input_dev *input_dev = tj9->input_dev;
unsigned int interval;
int error;
error = kstrtouint(buf, 10, &interval);
if (error < 0)
return error;
/* Lock the device to prevent races with open/close (and itself) */
mutex_lock(&input_dev->mutex);
disable_irq(client->irq);
/*
* Set current interval to the greater of the minimum interval or
* the requested interval
*/
tj9->last_poll_interval = max(interval, tj9->pdata.min_interval);
kxtj9_update_odr(tj9, tj9->last_poll_interval);
enable_irq(client->irq);
mutex_unlock(&input_dev->mutex);
return count;
}
static DEVICE_ATTR(poll, S_IRUGO|S_IWUSR, kxtj9_get_poll, kxtj9_set_poll);
static struct attribute *kxtj9_attrs[] = {
&dev_attr_poll.attr,
NULL
};
static umode_t kxtj9_attr_is_visible(struct kobject *kobj,
struct attribute *attr, int n)
{
struct device *dev = kobj_to_dev(kobj);
struct i2c_client *client = to_i2c_client(dev);
return client->irq ? attr->mode : 0;
}
static struct attribute_group kxtj9_group = {
.attrs = kxtj9_attrs,
.is_visible = kxtj9_attr_is_visible,
};
__ATTRIBUTE_GROUPS(kxtj9);
static void kxtj9_poll(struct input_dev *input)
{
struct kxtj9_data *tj9 = input_get_drvdata(input);
unsigned int poll_interval = input_get_poll_interval(input);
kxtj9_report_acceleration_data(tj9);
if (poll_interval != tj9->last_poll_interval) {
kxtj9_update_odr(tj9, poll_interval);
tj9->last_poll_interval = poll_interval;
}
}
static void kxtj9_platform_exit(void *data)
{
struct kxtj9_data *tj9 = data;
if (tj9->pdata.exit)
tj9->pdata.exit();
}
static int kxtj9_verify(struct kxtj9_data *tj9)
{
int retval;
retval = kxtj9_device_power_on(tj9);
if (retval < 0)
return retval;
retval = i2c_smbus_read_byte_data(tj9->client, WHO_AM_I);
if (retval < 0) {
dev_err(&tj9->client->dev, "read err int source\n");
goto out;
}
retval = (retval != 0x07 && retval != 0x08) ? -EIO : 0;
out:
kxtj9_device_power_off(tj9);
return retval;
}
static int kxtj9_probe(struct i2c_client *client)
{
const struct kxtj9_platform_data *pdata =
dev_get_platdata(&client->dev);
struct kxtj9_data *tj9;
struct input_dev *input_dev;
int err;
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_I2C | I2C_FUNC_SMBUS_BYTE_DATA)) {
dev_err(&client->dev, "client is not i2c capable\n");
return -ENXIO;
}
if (!pdata) {
dev_err(&client->dev, "platform data is NULL; exiting\n");
return -EINVAL;
}
tj9 = devm_kzalloc(&client->dev, sizeof(*tj9), GFP_KERNEL);
if (!tj9) {
dev_err(&client->dev,
"failed to allocate memory for module data\n");
return -ENOMEM;
}
tj9->client = client;
tj9->pdata = *pdata;
if (pdata->init) {
err = pdata->init();
if (err < 0)
return err;
}
err = devm_add_action_or_reset(&client->dev, kxtj9_platform_exit, tj9);
if (err)
return err;
err = kxtj9_verify(tj9);
if (err < 0) {
dev_err(&client->dev, "device not recognized\n");
return err;
}
i2c_set_clientdata(client, tj9);
tj9->ctrl_reg1 = tj9->pdata.res_12bit | tj9->pdata.g_range;
tj9->last_poll_interval = tj9->pdata.init_interval;
input_dev = devm_input_allocate_device(&client->dev);
if (!input_dev) {
dev_err(&client->dev, "input device allocate failed\n");
return -ENOMEM;
}
input_set_drvdata(input_dev, tj9);
tj9->input_dev = input_dev;
input_dev->name = "kxtj9_accel";
input_dev->id.bustype = BUS_I2C;
input_dev->open = kxtj9_input_open;
input_dev->close = kxtj9_input_close;
input_set_abs_params(input_dev, ABS_X, -G_MAX, G_MAX, FUZZ, FLAT);
input_set_abs_params(input_dev, ABS_Y, -G_MAX, G_MAX, FUZZ, FLAT);
input_set_abs_params(input_dev, ABS_Z, -G_MAX, G_MAX, FUZZ, FLAT);
if (client->irq <= 0) {
err = input_setup_polling(input_dev, kxtj9_poll);
if (err)
return err;
}
err = input_register_device(input_dev);
if (err) {
dev_err(&client->dev,
"unable to register input polled device %s: %d\n",
input_dev->name, err);
return err;
}
if (client->irq) {
/* If in irq mode, populate INT_CTRL_REG1 and enable DRDY. */
tj9->int_ctrl |= KXTJ9_IEN | KXTJ9_IEA | KXTJ9_IEL;
tj9->ctrl_reg1 |= DRDYE;
err = devm_request_threaded_irq(&client->dev, client->irq,
NULL, kxtj9_isr,
IRQF_TRIGGER_RISING |
IRQF_ONESHOT,
"kxtj9-irq", tj9);
if (err) {
dev_err(&client->dev, "request irq failed: %d\n", err);
return err;
}
}
return 0;
}
static int kxtj9_suspend(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct kxtj9_data *tj9 = i2c_get_clientdata(client);
struct input_dev *input_dev = tj9->input_dev;
mutex_lock(&input_dev->mutex);
if (input_device_enabled(input_dev))
kxtj9_disable(tj9);
mutex_unlock(&input_dev->mutex);
return 0;
}
static int kxtj9_resume(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct kxtj9_data *tj9 = i2c_get_clientdata(client);
struct input_dev *input_dev = tj9->input_dev;
mutex_lock(&input_dev->mutex);
if (input_device_enabled(input_dev))
kxtj9_enable(tj9);
mutex_unlock(&input_dev->mutex);
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(kxtj9_pm_ops, kxtj9_suspend, kxtj9_resume);
static const struct i2c_device_id kxtj9_id[] = {
{ NAME },
{ }
};
MODULE_DEVICE_TABLE(i2c, kxtj9_id);
static struct i2c_driver kxtj9_driver = {
.driver = {
.name = NAME,
.dev_groups = kxtj9_groups,
.pm = pm_sleep_ptr(&kxtj9_pm_ops),
},
.probe = kxtj9_probe,
.id_table = kxtj9_id,
};
module_i2c_driver(kxtj9_driver);
MODULE_DESCRIPTION("KXTJ9 accelerometer driver");
MODULE_AUTHOR("Chris Hudson <[email protected]>");
MODULE_LICENSE("GPL");
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