1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * IIO driver for the MiraMEMS DA311 3-axis accelerometer
4  *
5  * Copyright (c) 2016 Hans de Goede <hdegoede@redhat.com>
6  * Copyright (c) 2011-2013 MiraMEMS Sensing Technology Co., Ltd.
7  */
8 
9 #include <linux/module.h>
10 #include <linux/i2c.h>
11 #include <linux/iio/iio.h>
12 #include <linux/iio/sysfs.h>
13 #include <linux/byteorder/generic.h>
14 
15 #define DA311_CHIP_ID			0x13
16 
17 /*
18  * Note register addressed go from 0 - 0x3f and then wrap.
19  * For some reason there are 2 banks with 0 - 0x3f addresses,
20  * rather then a single 0-0x7f bank.
21  */
22 
23 /* Bank 0 regs */
24 #define DA311_REG_BANK			0x0000
25 #define DA311_REG_LDO_REG		0x0006
26 #define DA311_REG_CHIP_ID		0x000f
27 #define DA311_REG_TEMP_CFG_REG		0x001f
28 #define DA311_REG_CTRL_REG1		0x0020
29 #define DA311_REG_CTRL_REG3		0x0022
30 #define DA311_REG_CTRL_REG4		0x0023
31 #define DA311_REG_CTRL_REG5		0x0024
32 #define DA311_REG_CTRL_REG6		0x0025
33 #define DA311_REG_STATUS_REG		0x0027
34 #define DA311_REG_OUT_X_L		0x0028
35 #define DA311_REG_OUT_X_H		0x0029
36 #define DA311_REG_OUT_Y_L		0x002a
37 #define DA311_REG_OUT_Y_H		0x002b
38 #define DA311_REG_OUT_Z_L		0x002c
39 #define DA311_REG_OUT_Z_H		0x002d
40 #define DA311_REG_INT1_CFG		0x0030
41 #define DA311_REG_INT1_SRC		0x0031
42 #define DA311_REG_INT1_THS		0x0032
43 #define DA311_REG_INT1_DURATION		0x0033
44 #define DA311_REG_INT2_CFG		0x0034
45 #define DA311_REG_INT2_SRC		0x0035
46 #define DA311_REG_INT2_THS		0x0036
47 #define DA311_REG_INT2_DURATION		0x0037
48 #define DA311_REG_CLICK_CFG		0x0038
49 #define DA311_REG_CLICK_SRC		0x0039
50 #define DA311_REG_CLICK_THS		0x003a
51 #define DA311_REG_TIME_LIMIT		0x003b
52 #define DA311_REG_TIME_LATENCY		0x003c
53 #define DA311_REG_TIME_WINDOW		0x003d
54 
55 /* Bank 1 regs */
56 #define DA311_REG_SOFT_RESET		0x0105
57 #define DA311_REG_OTP_XOFF_L		0x0110
58 #define DA311_REG_OTP_XOFF_H		0x0111
59 #define DA311_REG_OTP_YOFF_L		0x0112
60 #define DA311_REG_OTP_YOFF_H		0x0113
61 #define DA311_REG_OTP_ZOFF_L		0x0114
62 #define DA311_REG_OTP_ZOFF_H		0x0115
63 #define DA311_REG_OTP_XSO		0x0116
64 #define DA311_REG_OTP_YSO		0x0117
65 #define DA311_REG_OTP_ZSO		0x0118
66 #define DA311_REG_OTP_TRIM_OSC		0x011b
67 #define DA311_REG_LPF_ABSOLUTE		0x011c
68 #define DA311_REG_TEMP_OFF1		0x0127
69 #define DA311_REG_TEMP_OFF2		0x0128
70 #define DA311_REG_TEMP_OFF3		0x0129
71 #define DA311_REG_OTP_TRIM_THERM_H	0x011a
72 
73 /*
74  * a value of + or -1024 corresponds to + or - 1G
75  * scale = 9.81 / 1024 = 0.009580078
76  */
77 
78 static const int da311_nscale = 9580078;
79 
80 #define DA311_CHANNEL(reg, axis) {	\
81 	.type = IIO_ACCEL,	\
82 	.address = reg,	\
83 	.modified = 1,	\
84 	.channel2 = IIO_MOD_##axis,	\
85 	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),	\
86 	.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),	\
87 }
88 
89 static const struct iio_chan_spec da311_channels[] = {
90 	/* | 0x80 comes from the android driver */
91 	DA311_CHANNEL(DA311_REG_OUT_X_L | 0x80, X),
92 	DA311_CHANNEL(DA311_REG_OUT_Y_L | 0x80, Y),
93 	DA311_CHANNEL(DA311_REG_OUT_Z_L | 0x80, Z),
94 };
95 
96 struct da311_data {
97 	struct i2c_client *client;
98 };
99 
da311_register_mask_write(struct i2c_client * client,u16 addr,u8 mask,u8 data)100 static int da311_register_mask_write(struct i2c_client *client, u16 addr,
101 				     u8 mask, u8 data)
102 {
103 	int ret;
104 	u8 tmp_data = 0;
105 
106 	if (addr & 0xff00) {
107 		/* Select bank 1 */
108 		ret = i2c_smbus_write_byte_data(client, DA311_REG_BANK, 0x01);
109 		if (ret < 0)
110 			return ret;
111 	}
112 
113 	if (mask != 0xff) {
114 		ret = i2c_smbus_read_byte_data(client, addr);
115 		if (ret < 0)
116 			return ret;
117 		tmp_data = ret;
118 	}
119 
120 	tmp_data &= ~mask;
121 	tmp_data |= data & mask;
122 	ret = i2c_smbus_write_byte_data(client, addr & 0xff, tmp_data);
123 	if (ret < 0)
124 		return ret;
125 
126 	if (addr & 0xff00) {
127 		/* Back to bank 0 */
128 		ret = i2c_smbus_write_byte_data(client, DA311_REG_BANK, 0x00);
129 		if (ret < 0)
130 			return ret;
131 	}
132 
133 	return 0;
134 }
135 
136 /* Init sequence taken from the android driver */
da311_reset(struct i2c_client * client)137 static int da311_reset(struct i2c_client *client)
138 {
139 	static const struct {
140 		u16 addr;
141 		u8 mask;
142 		u8 data;
143 	} init_data[] = {
144 		{ DA311_REG_TEMP_CFG_REG,       0xff,   0x08 },
145 		{ DA311_REG_CTRL_REG5,          0xff,   0x80 },
146 		{ DA311_REG_CTRL_REG4,          0x30,   0x00 },
147 		{ DA311_REG_CTRL_REG1,          0xff,   0x6f },
148 		{ DA311_REG_TEMP_CFG_REG,       0xff,   0x88 },
149 		{ DA311_REG_LDO_REG,            0xff,   0x02 },
150 		{ DA311_REG_OTP_TRIM_OSC,       0xff,   0x27 },
151 		{ DA311_REG_LPF_ABSOLUTE,       0xff,   0x30 },
152 		{ DA311_REG_TEMP_OFF1,          0xff,   0x3f },
153 		{ DA311_REG_TEMP_OFF2,          0xff,   0xff },
154 		{ DA311_REG_TEMP_OFF3,          0xff,   0x0f },
155 	};
156 	int i, ret;
157 
158 	/* Reset */
159 	ret = da311_register_mask_write(client, DA311_REG_SOFT_RESET,
160 					0xff, 0xaa);
161 	if (ret < 0)
162 		return ret;
163 
164 	for (i = 0; i < ARRAY_SIZE(init_data); i++) {
165 		ret = da311_register_mask_write(client,
166 						init_data[i].addr,
167 						init_data[i].mask,
168 						init_data[i].data);
169 		if (ret < 0)
170 			return ret;
171 	}
172 
173 	return 0;
174 }
175 
da311_enable(struct i2c_client * client,bool enable)176 static int da311_enable(struct i2c_client *client, bool enable)
177 {
178 	u8 data = enable ? 0x00 : 0x20;
179 
180 	return da311_register_mask_write(client, DA311_REG_TEMP_CFG_REG,
181 					 0x20, data);
182 }
183 
da311_read_raw(struct iio_dev * indio_dev,struct iio_chan_spec const * chan,int * val,int * val2,long mask)184 static int da311_read_raw(struct iio_dev *indio_dev,
185 				struct iio_chan_spec const *chan,
186 				int *val, int *val2, long mask)
187 {
188 	struct da311_data *data = iio_priv(indio_dev);
189 	int ret;
190 
191 	switch (mask) {
192 	case IIO_CHAN_INFO_RAW:
193 		ret = i2c_smbus_read_word_data(data->client, chan->address);
194 		if (ret < 0)
195 			return ret;
196 		/*
197 		 * Values are 12 bits, stored as 16 bits with the 4
198 		 * least significant bits always 0.
199 		 */
200 		*val = (short)ret >> 4;
201 		return IIO_VAL_INT;
202 	case IIO_CHAN_INFO_SCALE:
203 		*val = 0;
204 		*val2 = da311_nscale;
205 		return IIO_VAL_INT_PLUS_NANO;
206 	default:
207 		return -EINVAL;
208 	}
209 }
210 
211 static const struct iio_info da311_info = {
212 	.read_raw	= da311_read_raw,
213 };
214 
da311_disable(void * client)215 static void da311_disable(void *client)
216 {
217 	da311_enable(client, false);
218 }
219 
da311_probe(struct i2c_client * client)220 static int da311_probe(struct i2c_client *client)
221 {
222 	int ret;
223 	struct iio_dev *indio_dev;
224 	struct da311_data *data;
225 
226 	ret = i2c_smbus_read_byte_data(client, DA311_REG_CHIP_ID);
227 	if (ret != DA311_CHIP_ID)
228 		return (ret < 0) ? ret : -ENODEV;
229 
230 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
231 	if (!indio_dev)
232 		return -ENOMEM;
233 
234 	data = iio_priv(indio_dev);
235 	data->client = client;
236 
237 	indio_dev->info = &da311_info;
238 	indio_dev->name = "da311";
239 	indio_dev->modes = INDIO_DIRECT_MODE;
240 	indio_dev->channels = da311_channels;
241 	indio_dev->num_channels = ARRAY_SIZE(da311_channels);
242 
243 	ret = da311_reset(client);
244 	if (ret < 0)
245 		return ret;
246 
247 	ret = da311_enable(client, true);
248 	if (ret < 0)
249 		return ret;
250 
251 	ret = devm_add_action_or_reset(&client->dev, da311_disable, client);
252 	if (ret)
253 		return ret;
254 
255 	return devm_iio_device_register(&client->dev, indio_dev);
256 }
257 
da311_suspend(struct device * dev)258 static int da311_suspend(struct device *dev)
259 {
260 	return da311_enable(to_i2c_client(dev), false);
261 }
262 
da311_resume(struct device * dev)263 static int da311_resume(struct device *dev)
264 {
265 	return da311_enable(to_i2c_client(dev), true);
266 }
267 
268 static DEFINE_SIMPLE_DEV_PM_OPS(da311_pm_ops, da311_suspend, da311_resume);
269 
270 static const struct i2c_device_id da311_i2c_id[] = {
271 	{"da311", 0},
272 	{}
273 };
274 MODULE_DEVICE_TABLE(i2c, da311_i2c_id);
275 
276 static struct i2c_driver da311_driver = {
277 	.driver = {
278 		.name = "da311",
279 		.pm = pm_sleep_ptr(&da311_pm_ops),
280 	},
281 	.probe_new	= da311_probe,
282 	.id_table	= da311_i2c_id,
283 };
284 
285 module_i2c_driver(da311_driver);
286 
287 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
288 MODULE_DESCRIPTION("MiraMEMS DA311 3-Axis Accelerometer driver");
289 MODULE_LICENSE("GPL v2");
290