xref: /linux/drivers/iio/accel/da280.c (revision 40ccd6aa3e2e05be93394e3cd560c718dedfcc77)
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 
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 
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 
95 static void da280_disable(void *client)
96 {
97 	da280_enable(client, false);
98 }
99 
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 
141 static int da280_suspend(struct device *dev)
142 {
143 	return da280_enable(to_i2c_client(dev), false);
144 }
145 
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