drivers/input/misc/kxtj9.c - linux/torvalds/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * Copyright (C) 2011 Kionix, Inc.
  * Written by Chris Hudson <chudson@kionix.com>
  */

 #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_attributes[] = {
 	&dev_attr_poll.attr,
 	NULL
 };

 static struct attribute_group kxtj9_attribute_group = {
 	.attrs = kxtj9_attributes
 };

 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 i2c_device_id *id)
 {
 	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;
 		}

 		err = devm_device_add_group(&client->dev,
 					    &kxtj9_attribute_group);
 		if (err) {
 			dev_err(&client->dev, "sysfs create failed: %d\n", err);
 			return err;
 		}
 	}

 	return 0;
 }

 static int __maybe_unused 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_dev->users)
 		kxtj9_disable(tj9);

 	mutex_unlock(&input_dev->mutex);
 	return 0;
 }

 static int __maybe_unused 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_dev->users)
 		kxtj9_enable(tj9);

 	mutex_unlock(&input_dev->mutex);
 	return 0;
 }

 static SIMPLE_DEV_PM_OPS(kxtj9_pm_ops, kxtj9_suspend, kxtj9_resume);

 static const struct i2c_device_id kxtj9_id[] = {
 	{ NAME, 0 },
 	{ },
 };

 MODULE_DEVICE_TABLE(i2c, kxtj9_id);

 static struct i2c_driver kxtj9_driver = {
 	.driver = {
 		.name	= NAME,
 		.pm	= &kxtj9_pm_ops,
 	},
 	.probe		= kxtj9_probe,
 	.id_table	= kxtj9_id,
 };

 module_i2c_driver(kxtj9_driver);

 MODULE_DESCRIPTION("KXTJ9 accelerometer driver");
 MODULE_AUTHOR("Chris Hudson <chudson@kionix.com>");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* Copyright (C) 2011 Kionix, Inc.
	* Written by Chris Hudson <chudson@kionix.com>
	*/

	#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_attributes[] = {
	&dev_attr_poll.attr,
	NULL
	};

	static struct attribute_group kxtj9_attribute_group = {
	.attrs = kxtj9_attributes
	};

	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 i2c_device_id *id)
	{
	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;
	}

	err = devm_device_add_group(&client->dev,
	&kxtj9_attribute_group);
	if (err) {
	dev_err(&client->dev, "sysfs create failed: %d\n", err);
	return err;
	}
	}

	return 0;
	}

	static int __maybe_unused 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_dev->users)
	kxtj9_disable(tj9);

	mutex_unlock(&input_dev->mutex);
	return 0;
	}

	static int __maybe_unused 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_dev->users)
	kxtj9_enable(tj9);

	mutex_unlock(&input_dev->mutex);
	return 0;
	}

	static SIMPLE_DEV_PM_OPS(kxtj9_pm_ops, kxtj9_suspend, kxtj9_resume);

	static const struct i2c_device_id kxtj9_id[] = {
	{ NAME, 0 },
	{ },
	};

	MODULE_DEVICE_TABLE(i2c, kxtj9_id);

	static struct i2c_driver kxtj9_driver = {
	.driver = {
	.name = NAME,
	.pm = &kxtj9_pm_ops,
	},
	.probe = kxtj9_probe,
	.id_table = kxtj9_id,
	};

	module_i2c_driver(kxtj9_driver);

	MODULE_DESCRIPTION("KXTJ9 accelerometer driver");
	MODULE_AUTHOR("Chris Hudson <chudson@kionix.com>");
	MODULE_LICENSE("GPL");