1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * IIO driver for the MiraMEMS DA217 and DA280 3-axis accelerometer and
4 * IIO driver for the MiraMEMS DA226 2-axis accelerometer
5 *
6 * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
7 */
8
9 #include <linux/module.h>
10 #include <linux/i2c.h>
11 #include <linux/acpi.h>
12 #include <linux/iio/iio.h>
13 #include <linux/iio/sysfs.h>
14 #include <linux/byteorder/generic.h>
15
16 #define DA280_REG_CHIP_ID 0x01
17 #define DA280_REG_ACC_X_LSB 0x02
18 #define DA280_REG_ACC_Y_LSB 0x04
19 #define DA280_REG_ACC_Z_LSB 0x06
20 #define DA280_REG_MODE_BW 0x11
21
22 #define DA280_CHIP_ID 0x13
23 #define DA280_MODE_ENABLE 0x1e
24 #define DA280_MODE_DISABLE 0x9e
25
26 /*
27 * a value of + or -4096 corresponds to + or - 1G
28 * scale = 9.81 / 4096 = 0.002395019
29 */
30
31 static const int da280_nscale = 2395019;
32
33 #define DA280_CHANNEL(reg, axis) { \
34 .type = IIO_ACCEL, \
35 .address = reg, \
36 .modified = 1, \
37 .channel2 = IIO_MOD_##axis, \
38 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
39 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
40 }
41
42 static const struct iio_chan_spec da280_channels[] = {
43 DA280_CHANNEL(DA280_REG_ACC_X_LSB, X),
44 DA280_CHANNEL(DA280_REG_ACC_Y_LSB, Y),
45 DA280_CHANNEL(DA280_REG_ACC_Z_LSB, Z),
46 };
47
48 struct da280_match_data {
49 const char *name;
50 int num_channels;
51 };
52
53 struct da280_data {
54 struct i2c_client *client;
55 };
56
da280_enable(struct i2c_client * client,bool enable)57 static int da280_enable(struct i2c_client *client, bool enable)
58 {
59 u8 data = enable ? DA280_MODE_ENABLE : DA280_MODE_DISABLE;
60
61 return i2c_smbus_write_byte_data(client, DA280_REG_MODE_BW, data);
62 }
63
da280_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)64 static int da280_read_raw(struct iio_dev *indio_dev,
65 struct iio_chan_spec const *chan,
66 int *val, int *val2, long mask)
67 {
68 struct da280_data *data = iio_priv(indio_dev);
69 int ret;
70
71 switch (mask) {
72 case IIO_CHAN_INFO_RAW:
73 ret = i2c_smbus_read_word_data(data->client, chan->address);
74 if (ret < 0)
75 return ret;
76 /*
77 * Values are 14 bits, stored as 16 bits with the 2
78 * least significant bits always 0.
79 */
80 *val = (short)ret >> 2;
81 return IIO_VAL_INT;
82 case IIO_CHAN_INFO_SCALE:
83 *val = 0;
84 *val2 = da280_nscale;
85 return IIO_VAL_INT_PLUS_NANO;
86 default:
87 return -EINVAL;
88 }
89 }
90
91 static const struct iio_info da280_info = {
92 .read_raw = da280_read_raw,
93 };
94
da280_disable(void * client)95 static void da280_disable(void *client)
96 {
97 da280_enable(client, false);
98 }
99
da280_probe(struct i2c_client * client)100 static int da280_probe(struct i2c_client *client)
101 {
102 const struct da280_match_data *match_data;
103 struct iio_dev *indio_dev;
104 struct da280_data *data;
105 int ret;
106
107 ret = i2c_smbus_read_byte_data(client, DA280_REG_CHIP_ID);
108 if (ret != DA280_CHIP_ID)
109 return (ret < 0) ? ret : -ENODEV;
110
111 match_data = i2c_get_match_data(client);
112 if (!match_data) {
113 dev_err(&client->dev, "Error match-data not set\n");
114 return -EINVAL;
115 }
116
117 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
118 if (!indio_dev)
119 return -ENOMEM;
120
121 data = iio_priv(indio_dev);
122 data->client = client;
123
124 indio_dev->info = &da280_info;
125 indio_dev->modes = INDIO_DIRECT_MODE;
126 indio_dev->channels = da280_channels;
127 indio_dev->num_channels = match_data->num_channels;
128 indio_dev->name = match_data->name;
129
130 ret = da280_enable(client, true);
131 if (ret < 0)
132 return ret;
133
134 ret = devm_add_action_or_reset(&client->dev, da280_disable, client);
135 if (ret)
136 return ret;
137
138 return devm_iio_device_register(&client->dev, indio_dev);
139 }
140
da280_suspend(struct device * dev)141 static int da280_suspend(struct device *dev)
142 {
143 return da280_enable(to_i2c_client(dev), false);
144 }
145
da280_resume(struct device * dev)146 static int da280_resume(struct device *dev)
147 {
148 return da280_enable(to_i2c_client(dev), true);
149 }
150
151 static DEFINE_SIMPLE_DEV_PM_OPS(da280_pm_ops, da280_suspend, da280_resume);
152
153 static const struct da280_match_data da217_match_data = { "da217", 3 };
154 static const struct da280_match_data da226_match_data = { "da226", 2 };
155 static const struct da280_match_data da280_match_data = { "da280", 3 };
156
157 static const struct acpi_device_id da280_acpi_match[] = {
158 { "NSA2513", (kernel_ulong_t)&da217_match_data },
159 { "MIRAACC", (kernel_ulong_t)&da280_match_data },
160 {}
161 };
162 MODULE_DEVICE_TABLE(acpi, da280_acpi_match);
163
164 static const struct i2c_device_id da280_i2c_id[] = {
165 { "da217", (kernel_ulong_t)&da217_match_data },
166 { "da226", (kernel_ulong_t)&da226_match_data },
167 { "da280", (kernel_ulong_t)&da280_match_data },
168 {}
169 };
170 MODULE_DEVICE_TABLE(i2c, da280_i2c_id);
171
172 static struct i2c_driver da280_driver = {
173 .driver = {
174 .name = "da280",
175 .acpi_match_table = da280_acpi_match,
176 .pm = pm_sleep_ptr(&da280_pm_ops),
177 },
178 .probe = da280_probe,
179 .id_table = da280_i2c_id,
180 };
181
182 module_i2c_driver(da280_driver);
183
184 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
185 MODULE_DESCRIPTION("MiraMEMS DA280 3-Axis Accelerometer driver");
186 MODULE_LICENSE("GPL v2");
187