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 enum da280_chipset { da217, da226, da280 };
27
28 /*
29 * a value of + or -4096 corresponds to + or - 1G
30 * scale = 9.81 / 4096 = 0.002395019
31 */
32
33 static const int da280_nscale = 2395019;
34
35 #define DA280_CHANNEL(reg, axis) { \
36 .type = IIO_ACCEL, \
37 .address = reg, \
38 .modified = 1, \
39 .channel2 = IIO_MOD_##axis, \
40 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
41 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
42 }
43
44 static const struct iio_chan_spec da280_channels[] = {
45 DA280_CHANNEL(DA280_REG_ACC_X_LSB, X),
46 DA280_CHANNEL(DA280_REG_ACC_Y_LSB, Y),
47 DA280_CHANNEL(DA280_REG_ACC_Z_LSB, Z),
48 };
49
50 struct da280_data {
51 struct i2c_client *client;
52 };
53
da280_enable(struct i2c_client * client,bool enable)54 static int da280_enable(struct i2c_client *client, bool enable)
55 {
56 u8 data = enable ? DA280_MODE_ENABLE : DA280_MODE_DISABLE;
57
58 return i2c_smbus_write_byte_data(client, DA280_REG_MODE_BW, data);
59 }
60
da280_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)61 static int da280_read_raw(struct iio_dev *indio_dev,
62 struct iio_chan_spec const *chan,
63 int *val, int *val2, long mask)
64 {
65 struct da280_data *data = iio_priv(indio_dev);
66 int ret;
67
68 switch (mask) {
69 case IIO_CHAN_INFO_RAW:
70 ret = i2c_smbus_read_word_data(data->client, chan->address);
71 if (ret < 0)
72 return ret;
73 /*
74 * Values are 14 bits, stored as 16 bits with the 2
75 * least significant bits always 0.
76 */
77 *val = (short)ret >> 2;
78 return IIO_VAL_INT;
79 case IIO_CHAN_INFO_SCALE:
80 *val = 0;
81 *val2 = da280_nscale;
82 return IIO_VAL_INT_PLUS_NANO;
83 default:
84 return -EINVAL;
85 }
86 }
87
88 static const struct iio_info da280_info = {
89 .read_raw = da280_read_raw,
90 };
91
da280_match_acpi_device(struct device * dev)92 static enum da280_chipset da280_match_acpi_device(struct device *dev)
93 {
94 const struct acpi_device_id *id;
95
96 id = acpi_match_device(dev->driver->acpi_match_table, dev);
97 if (!id)
98 return -EINVAL;
99
100 return (enum da280_chipset) id->driver_data;
101 }
102
da280_disable(void * client)103 static void da280_disable(void *client)
104 {
105 da280_enable(client, false);
106 }
107
da280_probe(struct i2c_client * client)108 static int da280_probe(struct i2c_client *client)
109 {
110 const struct i2c_device_id *id = i2c_client_get_device_id(client);
111 int ret;
112 struct iio_dev *indio_dev;
113 struct da280_data *data;
114 enum da280_chipset chip;
115
116 ret = i2c_smbus_read_byte_data(client, DA280_REG_CHIP_ID);
117 if (ret != DA280_CHIP_ID)
118 return (ret < 0) ? ret : -ENODEV;
119
120 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
121 if (!indio_dev)
122 return -ENOMEM;
123
124 data = iio_priv(indio_dev);
125 data->client = client;
126
127 indio_dev->info = &da280_info;
128 indio_dev->modes = INDIO_DIRECT_MODE;
129 indio_dev->channels = da280_channels;
130
131 if (ACPI_HANDLE(&client->dev)) {
132 chip = da280_match_acpi_device(&client->dev);
133 } else {
134 chip = id->driver_data;
135 }
136
137 if (chip == da217) {
138 indio_dev->name = "da217";
139 indio_dev->num_channels = 3;
140 } else if (chip == da226) {
141 indio_dev->name = "da226";
142 indio_dev->num_channels = 2;
143 } else {
144 indio_dev->name = "da280";
145 indio_dev->num_channels = 3;
146 }
147
148 ret = da280_enable(client, true);
149 if (ret < 0)
150 return ret;
151
152 ret = devm_add_action_or_reset(&client->dev, da280_disable, client);
153 if (ret)
154 return ret;
155
156 return devm_iio_device_register(&client->dev, indio_dev);
157 }
158
da280_suspend(struct device * dev)159 static int da280_suspend(struct device *dev)
160 {
161 return da280_enable(to_i2c_client(dev), false);
162 }
163
da280_resume(struct device * dev)164 static int da280_resume(struct device *dev)
165 {
166 return da280_enable(to_i2c_client(dev), true);
167 }
168
169 static DEFINE_SIMPLE_DEV_PM_OPS(da280_pm_ops, da280_suspend, da280_resume);
170
171 static const struct acpi_device_id da280_acpi_match[] = {
172 {"NSA2513", da217},
173 {"MIRAACC", da280},
174 {},
175 };
176 MODULE_DEVICE_TABLE(acpi, da280_acpi_match);
177
178 static const struct i2c_device_id da280_i2c_id[] = {
179 { "da217", da217 },
180 { "da226", da226 },
181 { "da280", da280 },
182 {}
183 };
184 MODULE_DEVICE_TABLE(i2c, da280_i2c_id);
185
186 static struct i2c_driver da280_driver = {
187 .driver = {
188 .name = "da280",
189 .acpi_match_table = ACPI_PTR(da280_acpi_match),
190 .pm = pm_sleep_ptr(&da280_pm_ops),
191 },
192 .probe = da280_probe,
193 .id_table = da280_i2c_id,
194 };
195
196 module_i2c_driver(da280_driver);
197
198 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
199 MODULE_DESCRIPTION("MiraMEMS DA280 3-Axis Accelerometer driver");
200 MODULE_LICENSE("GPL v2");
201