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
31static 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
42static 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
48struct da280_match_data {
49	const char *name;
50	int num_channels;
51};
52
53struct da280_data {
54	struct i2c_client *client;
55};
56
57static 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
64static 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
91static const struct iio_info da280_info = {
92	.read_raw	= da280_read_raw,
93};
94
95static void da280_disable(void *client)
96{
97	da280_enable(client, false);
98}
99
100static 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
141static int da280_suspend(struct device *dev)
142{
143	return da280_enable(to_i2c_client(dev), false);
144}
145
146static int da280_resume(struct device *dev)
147{
148	return da280_enable(to_i2c_client(dev), true);
149}
150
151static DEFINE_SIMPLE_DEV_PM_OPS(da280_pm_ops, da280_suspend, da280_resume);
152
153static const struct da280_match_data da217_match_data = { "da217", 3 };
154static const struct da280_match_data da226_match_data = { "da226", 2 };
155static const struct da280_match_data da280_match_data = { "da280", 3 };
156
157static 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};
162MODULE_DEVICE_TABLE(acpi, da280_acpi_match);
163
164static 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};
170MODULE_DEVICE_TABLE(i2c, da280_i2c_id);
171
172static 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
182module_i2c_driver(da280_driver);
183
184MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
185MODULE_DESCRIPTION("MiraMEMS DA280 3-Axis Accelerometer driver");
186MODULE_LICENSE("GPL v2");
187