// SPDX-License-Identifier: GPL-2.0-or-later/* *  Driver for Freescale's 3-Axis Accelerometer MMA8450 * *  Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved. */ #include <linux/kernel.h>#include <linux/module.h>#include <linux/slab.h>#include <linux/delay.h>#include <linux/i2c.h>#include <linux/input.h> #define MMA8450_DRV_NAME	"mma8450" #define MODE_CHANGE_DELAY_MS	100#define POLL_INTERVAL		100#define POLL_INTERVAL_MAX	500 /* register definitions */#define MMA8450_STATUS		0x00#define MMA8450_STATUS_ZXYDR	0x08 #define MMA8450_OUT_X8		0x01#define MMA8450_OUT_Y8		0x02#define MMA8450_OUT_Z8		0x03 #define MMA8450_OUT_X_LSB	0x05#define MMA8450_OUT_X_MSB	0x06#define MMA8450_OUT_Y_LSB	0x07#define MMA8450_OUT_Y_MSB	0x08#define MMA8450_OUT_Z_LSB	0x09#define MMA8450_OUT_Z_MSB	0x0a #define MMA8450_XYZ_DATA_CFG	0x16 #define MMA8450_CTRL_REG1	0x38#define MMA8450_CTRL_REG2	0x39#define MMA8450_ID		0xc6#define MMA8450_WHO_AM_I	0x0f static int mma8450_read(struct i2c_client *c, unsigned int off){	int ret; 	ret = i2c_smbus_read_byte_data(c, off);	if (ret < 0)		dev_err(&c->dev,			"failed to read register 0x%02x, error %d\n",			off, ret); 	return ret;} static int mma8450_write(struct i2c_client *c, unsigned int off, u8 v){	int error; 	error = i2c_smbus_write_byte_data(c, off, v);	if (error < 0) {		dev_err(&c->dev,			"failed to write to register 0x%02x, error %d\n",			off, error);		return error;	} 	return 0;} static int mma8450_read_block(struct i2c_client *c, unsigned int off,			      u8 *buf, size_t size){	int err; 	err = i2c_smbus_read_i2c_block_data(c, off, size, buf);	if (err < 0) {		dev_err(&c->dev,			"failed to read block data at 0x%02x, error %d\n",			MMA8450_OUT_X_LSB, err);		return err;	} 	return 0;} static void mma8450_poll(struct input_dev *input){	struct i2c_client *c = input_get_drvdata(input);	int x, y, z;	int ret;	u8 buf[6]; 	ret = mma8450_read(c, MMA8450_STATUS);	if (ret < 0)		return; 	if (!(ret & MMA8450_STATUS_ZXYDR))		return; 	ret = mma8450_read_block(c, MMA8450_OUT_X_LSB, buf, sizeof(buf));	if (ret < 0)		return; 	x = ((int)(s8)buf[1] << 4) | (buf[0] & 0xf);	y = ((int)(s8)buf[3] << 4) | (buf[2] & 0xf);	z = ((int)(s8)buf[5] << 4) | (buf[4] & 0xf); 	input_report_abs(input, ABS_X, x);	input_report_abs(input, ABS_Y, y);	input_report_abs(input, ABS_Z, z);	input_sync(input);} /* Initialize the MMA8450 chip */static int mma8450_open(struct input_dev *input){	struct i2c_client *c = input_get_drvdata(input);	int err; 	/* enable all events from X/Y/Z, no FIFO */	err = mma8450_write(c, MMA8450_XYZ_DATA_CFG, 0x07);	if (err)		return err; 	/*	 * Sleep mode poll rate - 50Hz	 * System output data rate - 400Hz	 * Full scale selection - Active, +/- 2G	 */	err = mma8450_write(c, MMA8450_CTRL_REG1, 0x01);	if (err)		return err; 	msleep(MODE_CHANGE_DELAY_MS);	return 0;} static void mma8450_close(struct input_dev *input){	struct i2c_client *c = input_get_drvdata(input); 	mma8450_write(c, MMA8450_CTRL_REG1, 0x00);	mma8450_write(c, MMA8450_CTRL_REG2, 0x01);} /* * I2C init/probing/exit functions */static int mma8450_probe(struct i2c_client *c){	struct i2c_adapter *adapter = c->adapter;	struct input_dev *input;	int err, client_id; 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE |						I2C_FUNC_SMBUS_BYTE_DATA))		return dev_err_probe(&c->dev, -EINVAL,				     "I2C adapter doesn't support SMBUS BYTE"); 	client_id = i2c_smbus_read_byte_data(c, MMA8450_WHO_AM_I);	if (client_id != MMA8450_ID)		return dev_err_probe(&c->dev, -EINVAL,				     "unexpected chip ID 0x%x (vs 0x%x)\n",				     client_id, MMA8450_ID); 	input = devm_input_allocate_device(&c->dev);	if (!input)		return -ENOMEM; 	input_set_drvdata(input, c); 	input->name = MMA8450_DRV_NAME;	input->id.bustype = BUS_I2C; 	input->open = mma8450_open;	input->close = mma8450_close; 	input_set_abs_params(input, ABS_X, -2048, 2047, 32, 32);	input_set_abs_params(input, ABS_Y, -2048, 2047, 32, 32);	input_set_abs_params(input, ABS_Z, -2048, 2047, 32, 32); 	err = input_setup_polling(input, mma8450_poll);	if (err) {		dev_err(&c->dev, "failed to set up polling\n");		return err;	} 	input_set_poll_interval(input, POLL_INTERVAL);	input_set_max_poll_interval(input, POLL_INTERVAL_MAX); 	err = input_register_device(input);	if (err) {		dev_err(&c->dev, "failed to register input device\n");		return err;	} 	return 0;} static const struct i2c_device_id mma8450_id[] = {	{ .name = MMA8450_DRV_NAME },	{ }};MODULE_DEVICE_TABLE(i2c, mma8450_id); static const struct of_device_id mma8450_dt_ids[] = {	{ .compatible = "fsl,mma8450", },	{ /* sentinel */ }};MODULE_DEVICE_TABLE(of, mma8450_dt_ids); static struct i2c_driver mma8450_driver = {	.driver = {		.name	= MMA8450_DRV_NAME,		.of_match_table = mma8450_dt_ids,	},	.probe		= mma8450_probe,	.id_table	= mma8450_id,}; module_i2c_driver(mma8450_driver); MODULE_AUTHOR("Freescale Semiconductor, Inc.");MODULE_DESCRIPTION("MMA8450 3-Axis Accelerometer Driver");MODULE_LICENSE("GPL");