1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * mCube MC3230 3-Axis Accelerometer
4  *
5  * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
6  *
7  * IIO driver for mCube MC3230; 7-bit I2C address: 0x4c.
8  */
9 
10 #include <linux/i2c.h>
11 #include <linux/module.h>
12 #include <linux/iio/iio.h>
13 #include <linux/iio/sysfs.h>
14 
15 #define MC3230_REG_XOUT			0x00
16 #define MC3230_REG_YOUT			0x01
17 #define MC3230_REG_ZOUT			0x02
18 
19 #define MC3230_REG_MODE			0x07
20 #define MC3230_MODE_OPCON_MASK		0x03
21 #define MC3230_MODE_OPCON_WAKE		0x01
22 #define MC3230_MODE_OPCON_STANDBY	0x03
23 
24 #define MC3230_REG_CHIP_ID		0x18
25 #define MC3230_REG_PRODUCT_CODE		0x3b
26 
27 /*
28  * The accelerometer has one measurement range:
29  *
30  * -1.5g - +1.5g (8-bit, signed)
31  *
32  */
33 
34 struct mc3230_chip_info {
35 	const char *name;
36 	const u8 chip_id;
37 	const u8 product_code;
38 	const int scale;
39 };
40 
41 static const struct mc3230_chip_info mc3230_chip_info = {
42 	.name = "mc3230",
43 	.chip_id = 0x01,
44 	.product_code = 0x19,
45 	/* (1.5 + 1.5) * 9.81 / (2^8 - 1) = 0.115411765 */
46 	.scale = 115411765,
47 };
48 
49 static const struct mc3230_chip_info mc3510c_chip_info = {
50 	.name = "mc3510c",
51 	.chip_id = 0x23,
52 	.product_code = 0x10,
53 	/* Was obtained empirically */
54 	.scale = 625000000,
55 };
56 
57 #define MC3230_CHANNEL(reg, axis) {	\
58 	.type = IIO_ACCEL,	\
59 	.address = reg,	\
60 	.modified = 1,	\
61 	.channel2 = IIO_MOD_##axis,	\
62 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
63 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
64 	.ext_info = mc3230_ext_info, \
65 }
66 
67 struct mc3230_data {
68 	const struct mc3230_chip_info *chip_info;
69 	struct i2c_client *client;
70 	struct iio_mount_matrix orientation;
71 };
72 
73 static const struct iio_mount_matrix *
74 mc3230_get_mount_matrix(const struct iio_dev *indio_dev,
75 			const struct iio_chan_spec *chan)
76 {
77 	struct mc3230_data *data = iio_priv(indio_dev);
78 
79 	return &data->orientation;
80 }
81 
82 static const struct iio_chan_spec_ext_info mc3230_ext_info[] = {
83 	IIO_MOUNT_MATRIX(IIO_SHARED_BY_DIR, mc3230_get_mount_matrix),
84 	{ }
85 };
86 
87 static const struct iio_chan_spec mc3230_channels[] = {
88 	MC3230_CHANNEL(MC3230_REG_XOUT, X),
89 	MC3230_CHANNEL(MC3230_REG_YOUT, Y),
90 	MC3230_CHANNEL(MC3230_REG_ZOUT, Z),
91 };
92 
93 static int mc3230_set_opcon(struct mc3230_data *data, int opcon)
94 {
95 	int ret;
96 	struct i2c_client *client = data->client;
97 
98 	ret = i2c_smbus_read_byte_data(client, MC3230_REG_MODE);
99 	if (ret < 0) {
100 		dev_err(&client->dev, "failed to read mode reg: %d\n", ret);
101 		return ret;
102 	}
103 
104 	ret &= ~MC3230_MODE_OPCON_MASK;
105 	ret |= opcon;
106 
107 	ret = i2c_smbus_write_byte_data(client, MC3230_REG_MODE, ret);
108 	if (ret < 0) {
109 		dev_err(&client->dev, "failed to write mode reg: %d\n", ret);
110 		return ret;
111 	}
112 
113 	return 0;
114 }
115 
116 static int mc3230_read_raw(struct iio_dev *indio_dev,
117 				struct iio_chan_spec const *chan,
118 				int *val, int *val2, long mask)
119 {
120 	struct mc3230_data *data = iio_priv(indio_dev);
121 	int ret;
122 
123 	switch (mask) {
124 	case IIO_CHAN_INFO_RAW:
125 		ret = i2c_smbus_read_byte_data(data->client, chan->address);
126 		if (ret < 0)
127 			return ret;
128 		*val = sign_extend32(ret, 7);
129 		return IIO_VAL_INT;
130 	case IIO_CHAN_INFO_SCALE:
131 		*val = 0;
132 		*val2 = data->chip_info->scale;
133 		return IIO_VAL_INT_PLUS_NANO;
134 	default:
135 		return -EINVAL;
136 	}
137 }
138 
139 static const struct iio_info mc3230_info = {
140 	.read_raw	= mc3230_read_raw,
141 };
142 
143 static int mc3230_probe(struct i2c_client *client)
144 {
145 	int ret;
146 	struct iio_dev *indio_dev;
147 	struct mc3230_data *data;
148 	const struct mc3230_chip_info *chip_info;
149 
150 	chip_info = i2c_get_match_data(client);
151 	if (chip_info == NULL) {
152 		dev_err(&client->dev, "failed to get match data");
153 		return -ENODATA;
154 	}
155 
156 	/* First check chip-id and product-id */
157 	ret = i2c_smbus_read_byte_data(client, MC3230_REG_CHIP_ID);
158 	if (ret != chip_info->chip_id) {
159 		dev_info(&client->dev,
160 			"chip id check fail: 0x%x != 0x%x !\n",
161 			ret, chip_info->chip_id);
162 	}
163 
164 	ret = i2c_smbus_read_byte_data(client, MC3230_REG_PRODUCT_CODE);
165 	if (ret != chip_info->product_code) {
166 		dev_info(&client->dev,
167 			"product code check fail: 0x%x != 0x%x !\n",
168 			ret, chip_info->product_code);
169 	}
170 
171 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
172 	if (!indio_dev) {
173 		dev_err(&client->dev, "iio allocation failed!\n");
174 		return -ENOMEM;
175 	}
176 
177 	data = iio_priv(indio_dev);
178 	data->chip_info = chip_info;
179 	data->client = client;
180 	i2c_set_clientdata(client, indio_dev);
181 
182 	indio_dev->info = &mc3230_info;
183 	indio_dev->name = chip_info->name;
184 	indio_dev->modes = INDIO_DIRECT_MODE;
185 	indio_dev->channels = mc3230_channels;
186 	indio_dev->num_channels = ARRAY_SIZE(mc3230_channels);
187 
188 	ret = mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
189 	if (ret < 0)
190 		return ret;
191 
192 	ret = iio_read_mount_matrix(&client->dev, &data->orientation);
193 	if (ret)
194 		return ret;
195 
196 	ret = iio_device_register(indio_dev);
197 	if (ret < 0) {
198 		dev_err(&client->dev, "device_register failed\n");
199 		mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
200 	}
201 
202 	return ret;
203 }
204 
205 static void mc3230_remove(struct i2c_client *client)
206 {
207 	struct iio_dev *indio_dev = i2c_get_clientdata(client);
208 
209 	iio_device_unregister(indio_dev);
210 
211 	mc3230_set_opcon(iio_priv(indio_dev), MC3230_MODE_OPCON_STANDBY);
212 }
213 
214 static int mc3230_suspend(struct device *dev)
215 {
216 	struct mc3230_data *data;
217 
218 	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
219 
220 	return mc3230_set_opcon(data, MC3230_MODE_OPCON_STANDBY);
221 }
222 
223 static int mc3230_resume(struct device *dev)
224 {
225 	struct mc3230_data *data;
226 
227 	data = iio_priv(i2c_get_clientdata(to_i2c_client(dev)));
228 
229 	return mc3230_set_opcon(data, MC3230_MODE_OPCON_WAKE);
230 }
231 
232 static DEFINE_SIMPLE_DEV_PM_OPS(mc3230_pm_ops, mc3230_suspend, mc3230_resume);
233 
234 static const struct i2c_device_id mc3230_i2c_id[] = {
235 	{ "mc3230", (kernel_ulong_t)&mc3230_chip_info },
236 	{ "mc3510c", (kernel_ulong_t)&mc3510c_chip_info },
237 	{ }
238 };
239 MODULE_DEVICE_TABLE(i2c, mc3230_i2c_id);
240 
241 static const struct of_device_id mc3230_of_match[] = {
242 	{ .compatible = "mcube,mc3230", &mc3230_chip_info },
243 	{ .compatible = "mcube,mc3510c", &mc3510c_chip_info },
244 	{ }
245 };
246 MODULE_DEVICE_TABLE(of, mc3230_of_match);
247 
248 static struct i2c_driver mc3230_driver = {
249 	.driver = {
250 		.name = "mc3230",
251 		.of_match_table = mc3230_of_match,
252 		.pm = pm_sleep_ptr(&mc3230_pm_ops),
253 	},
254 	.probe		= mc3230_probe,
255 	.remove		= mc3230_remove,
256 	.id_table	= mc3230_i2c_id,
257 };
258 
259 module_i2c_driver(mc3230_driver);
260 
261 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
262 MODULE_DESCRIPTION("mCube MC3230 3-Axis Accelerometer driver");
263 MODULE_LICENSE("GPL v2");
264