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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
15#define MMA8450_DRV_NAME "mma8450"
16
17#define MODE_CHANGE_DELAY_MS 100
18#define POLL_INTERVAL 100
19#define POLL_INTERVAL_MAX 500
20
21/* register definitions */
22#define MMA8450_STATUS 0x00
23#define MMA8450_STATUS_ZXYDR 0x08
24
25#define MMA8450_OUT_X8 0x01
26#define MMA8450_OUT_Y8 0x02
27#define MMA8450_OUT_Z8 0x03
28
29#define MMA8450_OUT_X_LSB 0x05
30#define MMA8450_OUT_X_MSB 0x06
31#define MMA8450_OUT_Y_LSB 0x07
32#define MMA8450_OUT_Y_MSB 0x08
33#define MMA8450_OUT_Z_LSB 0x09
34#define MMA8450_OUT_Z_MSB 0x0a
35
36#define MMA8450_XYZ_DATA_CFG 0x16
37
38#define MMA8450_CTRL_REG1 0x38
39#define MMA8450_CTRL_REG2 0x39
40#define MMA8450_ID 0xc6
41#define MMA8450_WHO_AM_I 0x0f
42
43static int mma8450_read(struct i2c_client *c, unsigned int off)
44{
45 int ret;
46
47 ret = i2c_smbus_read_byte_data(c, off);
48 if (ret < 0)
49 dev_err(&c->dev,
50 "failed to read register 0x%02x, error %d\n",
51 off, ret);
52
53 return ret;
54}
55
56static int mma8450_write(struct i2c_client *c, unsigned int off, u8 v)
57{
58 int error;
59
60 error = i2c_smbus_write_byte_data(c, off, v);
61 if (error < 0) {
62 dev_err(&c->dev,
63 "failed to write to register 0x%02x, error %d\n",
64 off, error);
65 return error;
66 }
67
68 return 0;
69}
70
71static int mma8450_read_block(struct i2c_client *c, unsigned int off,
72 u8 *buf, size_t size)
73{
74 int err;
75
76 err = i2c_smbus_read_i2c_block_data(c, off, size, buf);
77 if (err < 0) {
78 dev_err(&c->dev,
79 "failed to read block data at 0x%02x, error %d\n",
80 MMA8450_OUT_X_LSB, err);
81 return err;
82 }
83
84 return 0;
85}
86
87static void mma8450_poll(struct input_dev *input)
88{
89 struct i2c_client *c = input_get_drvdata(input);
90 int x, y, z;
91 int ret;
92 u8 buf[6];
93
94 ret = mma8450_read(c, MMA8450_STATUS);
95 if (ret < 0)
96 return;
97
98 if (!(ret & MMA8450_STATUS_ZXYDR))
99 return;
100
101 ret = mma8450_read_block(c, MMA8450_OUT_X_LSB, buf, sizeof(buf));
102 if (ret < 0)
103 return;
104
105 x = ((int)(s8)buf[1] << 4) | (buf[0] & 0xf);
106 y = ((int)(s8)buf[3] << 4) | (buf[2] & 0xf);
107 z = ((int)(s8)buf[5] << 4) | (buf[4] & 0xf);
108
109 input_report_abs(input, ABS_X, x);
110 input_report_abs(input, ABS_Y, y);
111 input_report_abs(input, ABS_Z, z);
112 input_sync(input);
113}
114
115/* Initialize the MMA8450 chip */
116static int mma8450_open(struct input_dev *input)
117{
118 struct i2c_client *c = input_get_drvdata(input);
119 int err;
120
121 /* enable all events from X/Y/Z, no FIFO */
122 err = mma8450_write(c, MMA8450_XYZ_DATA_CFG, 0x07);
123 if (err)
124 return err;
125
126 /*
127 * Sleep mode poll rate - 50Hz
128 * System output data rate - 400Hz
129 * Full scale selection - Active, +/- 2G
130 */
131 err = mma8450_write(c, MMA8450_CTRL_REG1, 0x01);
132 if (err)
133 return err;
134
135 msleep(MODE_CHANGE_DELAY_MS);
136 return 0;
137}
138
139static void mma8450_close(struct input_dev *input)
140{
141 struct i2c_client *c = input_get_drvdata(input);
142
143 mma8450_write(c, MMA8450_CTRL_REG1, 0x00);
144 mma8450_write(c, MMA8450_CTRL_REG2, 0x01);
145}
146
147/*
148 * I2C init/probing/exit functions
149 */
150static int mma8450_probe(struct i2c_client *c)
151{
152 struct i2c_adapter *adapter = c->adapter;
153 struct input_dev *input;
154 int err, client_id;
155
156 if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE |
157 I2C_FUNC_SMBUS_BYTE_DATA))
158 return dev_err_probe(&c->dev, -EINVAL,
159 "I2C adapter doesn't support SMBUS BYTE");
160
161 client_id = i2c_smbus_read_byte_data(c, MMA8450_WHO_AM_I);
162 if (client_id != MMA8450_ID)
163 return dev_err_probe(&c->dev, -EINVAL,
164 "unexpected chip ID 0x%x (vs 0x%x)\n",
165 client_id, MMA8450_ID);
166
167 input = devm_input_allocate_device(&c->dev);
168 if (!input)
169 return -ENOMEM;
170
171 input_set_drvdata(input, c);
172
173 input->name = MMA8450_DRV_NAME;
174 input->id.bustype = BUS_I2C;
175
176 input->open = mma8450_open;
177 input->close = mma8450_close;
178
179 input_set_abs_params(input, ABS_X, -2048, 2047, 32, 32);
180 input_set_abs_params(input, ABS_Y, -2048, 2047, 32, 32);
181 input_set_abs_params(input, ABS_Z, -2048, 2047, 32, 32);
182
183 err = input_setup_polling(input, mma8450_poll);
184 if (err) {
185 dev_err(&c->dev, "failed to set up polling\n");
186 return err;
187 }
188
189 input_set_poll_interval(input, POLL_INTERVAL);
190 input_set_max_poll_interval(input, POLL_INTERVAL_MAX);
191
192 err = input_register_device(input);
193 if (err) {
194 dev_err(&c->dev, "failed to register input device\n");
195 return err;
196 }
197
198 return 0;
199}
200
201static const struct i2c_device_id mma8450_id[] = {
202 { .name = MMA8450_DRV_NAME },
203 { }
204};
205MODULE_DEVICE_TABLE(i2c, mma8450_id);
206
207static const struct of_device_id mma8450_dt_ids[] = {
208 { .compatible = "fsl,mma8450", },
209 { /* sentinel */ }
210};
211MODULE_DEVICE_TABLE(of, mma8450_dt_ids);
212
213static struct i2c_driver mma8450_driver = {
214 .driver = {
215 .name = MMA8450_DRV_NAME,
216 .of_match_table = mma8450_dt_ids,
217 },
218 .probe = mma8450_probe,
219 .id_table = mma8450_id,
220};
221
222module_i2c_driver(mma8450_driver);
223
224MODULE_AUTHOR("Freescale Semiconductor, Inc.");
225MODULE_DESCRIPTION("MMA8450 3-Axis Accelerometer Driver");
226MODULE_LICENSE("GPL");