1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *  Driver for Freescale's 3-Axis Accelerometer MMA8450
4 *
5 *  Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
6 */
7
8#include <linux/kernel.h>
9#include <linux/module.h>
10#include <linux/slab.h>
11#include <linux/delay.h>
12#include <linux/i2c.h>
13#include <linux/input.h>
14#include <linux/mod_devicetable.h>
15
16#define MMA8450_DRV_NAME	"mma8450"
17
18#define MODE_CHANGE_DELAY_MS	100
19#define POLL_INTERVAL		100
20#define POLL_INTERVAL_MAX	500
21
22/* register definitions */
23#define MMA8450_STATUS		0x00
24#define MMA8450_STATUS_ZXYDR	0x08
25
26#define MMA8450_OUT_X8		0x01
27#define MMA8450_OUT_Y8		0x02
28#define MMA8450_OUT_Z8		0x03
29
30#define MMA8450_OUT_X_LSB	0x05
31#define MMA8450_OUT_X_MSB	0x06
32#define MMA8450_OUT_Y_LSB	0x07
33#define MMA8450_OUT_Y_MSB	0x08
34#define MMA8450_OUT_Z_LSB	0x09
35#define MMA8450_OUT_Z_MSB	0x0a
36
37#define MMA8450_XYZ_DATA_CFG	0x16
38
39#define MMA8450_CTRL_REG1	0x38
40#define MMA8450_CTRL_REG2	0x39
41
42static int mma8450_read(struct i2c_client *c, unsigned int off)
43{
44	int ret;
45
46	ret = i2c_smbus_read_byte_data(c, off);
47	if (ret < 0)
48		dev_err(&c->dev,
49			"failed to read register 0x%02x, error %d\n",
50			off, ret);
51
52	return ret;
53}
54
55static int mma8450_write(struct i2c_client *c, unsigned int off, u8 v)
56{
57	int error;
58
59	error = i2c_smbus_write_byte_data(c, off, v);
60	if (error < 0) {
61		dev_err(&c->dev,
62			"failed to write to register 0x%02x, error %d\n",
63			off, error);
64		return error;
65	}
66
67	return 0;
68}
69
70static int mma8450_read_block(struct i2c_client *c, unsigned int off,
71			      u8 *buf, size_t size)
72{
73	int err;
74
75	err = i2c_smbus_read_i2c_block_data(c, off, size, buf);
76	if (err < 0) {
77		dev_err(&c->dev,
78			"failed to read block data at 0x%02x, error %d\n",
79			MMA8450_OUT_X_LSB, err);
80		return err;
81	}
82
83	return 0;
84}
85
86static void mma8450_poll(struct input_dev *input)
87{
88	struct i2c_client *c = input_get_drvdata(input);
89	int x, y, z;
90	int ret;
91	u8 buf[6];
92
93	ret = mma8450_read(c, MMA8450_STATUS);
94	if (ret < 0)
95		return;
96
97	if (!(ret & MMA8450_STATUS_ZXYDR))
98		return;
99
100	ret = mma8450_read_block(c, MMA8450_OUT_X_LSB, buf, sizeof(buf));
101	if (ret < 0)
102		return;
103
104	x = ((int)(s8)buf[1] << 4) | (buf[0] & 0xf);
105	y = ((int)(s8)buf[3] << 4) | (buf[2] & 0xf);
106	z = ((int)(s8)buf[5] << 4) | (buf[4] & 0xf);
107
108	input_report_abs(input, ABS_X, x);
109	input_report_abs(input, ABS_Y, y);
110	input_report_abs(input, ABS_Z, z);
111	input_sync(input);
112}
113
114/* Initialize the MMA8450 chip */
115static int mma8450_open(struct input_dev *input)
116{
117	struct i2c_client *c = input_get_drvdata(input);
118	int err;
119
120	/* enable all events from X/Y/Z, no FIFO */
121	err = mma8450_write(c, MMA8450_XYZ_DATA_CFG, 0x07);
122	if (err)
123		return err;
124
125	/*
126	 * Sleep mode poll rate - 50Hz
127	 * System output data rate - 400Hz
128	 * Full scale selection - Active, +/- 2G
129	 */
130	err = mma8450_write(c, MMA8450_CTRL_REG1, 0x01);
131	if (err)
132		return err;
133
134	msleep(MODE_CHANGE_DELAY_MS);
135	return 0;
136}
137
138static void mma8450_close(struct input_dev *input)
139{
140	struct i2c_client *c = input_get_drvdata(input);
141
142	mma8450_write(c, MMA8450_CTRL_REG1, 0x00);
143	mma8450_write(c, MMA8450_CTRL_REG2, 0x01);
144}
145
146/*
147 * I2C init/probing/exit functions
148 */
149static int mma8450_probe(struct i2c_client *c)
150{
151	struct input_dev *input;
152	int err;
153
154	input = devm_input_allocate_device(&c->dev);
155	if (!input)
156		return -ENOMEM;
157
158	input_set_drvdata(input, c);
159
160	input->name = MMA8450_DRV_NAME;
161	input->id.bustype = BUS_I2C;
162
163	input->open = mma8450_open;
164	input->close = mma8450_close;
165
166	input_set_abs_params(input, ABS_X, -2048, 2047, 32, 32);
167	input_set_abs_params(input, ABS_Y, -2048, 2047, 32, 32);
168	input_set_abs_params(input, ABS_Z, -2048, 2047, 32, 32);
169
170	err = input_setup_polling(input, mma8450_poll);
171	if (err) {
172		dev_err(&c->dev, "failed to set up polling\n");
173		return err;
174	}
175
176	input_set_poll_interval(input, POLL_INTERVAL);
177	input_set_max_poll_interval(input, POLL_INTERVAL_MAX);
178
179	err = input_register_device(input);
180	if (err) {
181		dev_err(&c->dev, "failed to register input device\n");
182		return err;
183	}
184
185	return 0;
186}
187
188static const struct i2c_device_id mma8450_id[] = {
189	{ MMA8450_DRV_NAME, 0 },
190	{ },
191};
192MODULE_DEVICE_TABLE(i2c, mma8450_id);
193
194static const struct of_device_id mma8450_dt_ids[] = {
195	{ .compatible = "fsl,mma8450", },
196	{ /* sentinel */ }
197};
198MODULE_DEVICE_TABLE(of, mma8450_dt_ids);
199
200static struct i2c_driver mma8450_driver = {
201	.driver = {
202		.name	= MMA8450_DRV_NAME,
203		.of_match_table = mma8450_dt_ids,
204	},
205	.probe		= mma8450_probe,
206	.id_table	= mma8450_id,
207};
208
209module_i2c_driver(mma8450_driver);
210
211MODULE_AUTHOR("Freescale Semiconductor, Inc.");
212MODULE_DESCRIPTION("MMA8450 3-Axis Accelerometer Driver");
213MODULE_LICENSE("GPL");
214