1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* IIO driver for the MiraMEMS DA280 3-axis accelerometer and
* IIO driver for the MiraMEMS DA226 2-axis accelerometer
*
* Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
*/
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/acpi.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/byteorder/generic.h>
#define DA280_REG_CHIP_ID 0x01
#define DA280_REG_ACC_X_LSB 0x02
#define DA280_REG_ACC_Y_LSB 0x04
#define DA280_REG_ACC_Z_LSB 0x06
#define DA280_REG_MODE_BW 0x11
#define DA280_CHIP_ID 0x13
#define DA280_MODE_ENABLE 0x1e
#define DA280_MODE_DISABLE 0x9e
enum da280_chipset { da226, da280 };
/*
* a value of + or -4096 corresponds to + or - 1G
* scale = 9.81 / 4096 = 0.002395019
*/
static const int da280_nscale = 2395019;
#define DA280_CHANNEL(reg, axis) { \
.type = IIO_ACCEL, \
.address = reg, \
.modified = 1, \
.channel2 = IIO_MOD_##axis, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
}
static const struct iio_chan_spec da280_channels[] = {
DA280_CHANNEL(DA280_REG_ACC_X_LSB, X),
DA280_CHANNEL(DA280_REG_ACC_Y_LSB, Y),
DA280_CHANNEL(DA280_REG_ACC_Z_LSB, Z),
};
struct da280_data {
struct i2c_client *client;
};
static int da280_enable(struct i2c_client *client, bool enable)
{
u8 data = enable ? DA280_MODE_ENABLE : DA280_MODE_DISABLE;
return i2c_smbus_write_byte_data(client, DA280_REG_MODE_BW, data);
}
static int da280_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct da280_data *data = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = i2c_smbus_read_word_data(data->client, chan->address);
if (ret < 0)
return ret;
/*
* Values are 14 bits, stored as 16 bits with the 2
* least significant bits always 0.
*/
*val = (short)ret >> 2;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
*val = 0;
*val2 = da280_nscale;
return IIO_VAL_INT_PLUS_NANO;
default:
return -EINVAL;
}
}
static const struct iio_info da280_info = {
.read_raw = da280_read_raw,
};
static enum da280_chipset da280_match_acpi_device(struct device *dev)
{
const struct acpi_device_id *id;
id = acpi_match_device(dev->driver->acpi_match_table, dev);
if (!id)
return -EINVAL;
return (enum da280_chipset) id->driver_data;
}
static void da280_disable(void *client)
{
da280_enable(client, false);
}
static int da280_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
int ret;
struct iio_dev *indio_dev;
struct da280_data *data;
enum da280_chipset chip;
ret = i2c_smbus_read_byte_data(client, DA280_REG_CHIP_ID);
if (ret != DA280_CHIP_ID)
return (ret < 0) ? ret : -ENODEV;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
data->client = client;
indio_dev->info = &da280_info;
indio_dev->modes = INDIO_DIRECT_MODE;
indio_dev->channels = da280_channels;
if (ACPI_HANDLE(&client->dev)) {
chip = da280_match_acpi_device(&client->dev);
} else {
chip = id->driver_data;
}
if (chip == da226) {
indio_dev->name = "da226";
indio_dev->num_channels = 2;
} else {
indio_dev->name = "da280";
indio_dev->num_channels = 3;
}
ret = da280_enable(client, true);
if (ret < 0)
return ret;
ret = devm_add_action_or_reset(&client->dev, da280_disable, client);
if (ret)
return ret;
return devm_iio_device_register(&client->dev, indio_dev);
}
static int da280_suspend(struct device *dev)
{
return da280_enable(to_i2c_client(dev), false);
}
static int da280_resume(struct device *dev)
{
return da280_enable(to_i2c_client(dev), true);
}
static DEFINE_SIMPLE_DEV_PM_OPS(da280_pm_ops, da280_suspend, da280_resume);
static const struct acpi_device_id da280_acpi_match[] = {
{"MIRAACC", da280},
{},
};
MODULE_DEVICE_TABLE(acpi, da280_acpi_match);
static const struct i2c_device_id da280_i2c_id[] = {
{ "da226", da226 },
{ "da280", da280 },
{}
};
MODULE_DEVICE_TABLE(i2c, da280_i2c_id);
static struct i2c_driver da280_driver = {
.driver = {
.name = "da280",
.acpi_match_table = ACPI_PTR(da280_acpi_match),
.pm = pm_sleep_ptr(&da280_pm_ops),
},
.probe = da280_probe,
.id_table = da280_i2c_id,
};
module_i2c_driver(da280_driver);
MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
MODULE_DESCRIPTION("MiraMEMS DA280 3-Axis Accelerometer driver");
MODULE_LICENSE("GPL v2");
|
