summaryrefslogtreecommitdiff
path: root/drivers/hwmon/ltc2990.c
blob: f9431ad43ad3b02a0b83e3e4990d56aa2f0fcdba (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Driver for Linear Technology LTC2990 power monitor
 *
 * Copyright (C) 2014 Topic Embedded Products
 * Author: Mike Looijmans <mike.looijmans@topic.nl>
 */

#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/i2c.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>

#define LTC2990_STATUS	0x00
#define LTC2990_CONTROL	0x01
#define LTC2990_TRIGGER	0x02
#define LTC2990_TINT_MSB	0x04
#define LTC2990_V1_MSB	0x06
#define LTC2990_V2_MSB	0x08
#define LTC2990_V3_MSB	0x0A
#define LTC2990_V4_MSB	0x0C
#define LTC2990_VCC_MSB	0x0E

#define LTC2990_IN0	BIT(0)
#define LTC2990_IN1	BIT(1)
#define LTC2990_IN2	BIT(2)
#define LTC2990_IN3	BIT(3)
#define LTC2990_IN4	BIT(4)
#define LTC2990_CURR1	BIT(5)
#define LTC2990_CURR2	BIT(6)
#define LTC2990_TEMP1	BIT(7)
#define LTC2990_TEMP2	BIT(8)
#define LTC2990_TEMP3	BIT(9)
#define LTC2990_NONE	0
#define LTC2990_ALL	GENMASK(9, 0)

#define LTC2990_MODE0_SHIFT	0
#define LTC2990_MODE0_MASK	GENMASK(2, 0)
#define LTC2990_MODE1_SHIFT	3
#define LTC2990_MODE1_MASK	GENMASK(1, 0)

/* Enabled measurements for mode bits 2..0 */
static const int ltc2990_attrs_ena_0[] = {
	LTC2990_IN1 | LTC2990_IN2 | LTC2990_TEMP3,
	LTC2990_CURR1 | LTC2990_TEMP3,
	LTC2990_CURR1 | LTC2990_IN3 | LTC2990_IN4,
	LTC2990_TEMP2 | LTC2990_IN3 | LTC2990_IN4,
	LTC2990_TEMP2 | LTC2990_CURR2,
	LTC2990_TEMP2 | LTC2990_TEMP3,
	LTC2990_CURR1 | LTC2990_CURR2,
	LTC2990_IN1 | LTC2990_IN2 | LTC2990_IN3 | LTC2990_IN4
};

/* Enabled measurements for mode bits 4..3 */
static const int ltc2990_attrs_ena_1[] = {
	LTC2990_NONE,
	LTC2990_TEMP2 | LTC2990_IN1 | LTC2990_CURR1,
	LTC2990_TEMP3 | LTC2990_IN3 | LTC2990_CURR2,
	LTC2990_ALL
};

struct ltc2990_data {
	struct i2c_client *i2c;
	u32 mode[2];
};

/* Return the converted value from the given register in uV or mC */
static int ltc2990_get_value(struct i2c_client *i2c, int index, int *result)
{
	int val;
	u8 reg;

	switch (index) {
	case LTC2990_IN0:
		reg = LTC2990_VCC_MSB;
		break;
	case LTC2990_IN1:
	case LTC2990_CURR1:
	case LTC2990_TEMP2:
		reg = LTC2990_V1_MSB;
		break;
	case LTC2990_IN2:
		reg = LTC2990_V2_MSB;
		break;
	case LTC2990_IN3:
	case LTC2990_CURR2:
	case LTC2990_TEMP3:
		reg = LTC2990_V3_MSB;
		break;
	case LTC2990_IN4:
		reg = LTC2990_V4_MSB;
		break;
	case LTC2990_TEMP1:
		reg = LTC2990_TINT_MSB;
		break;
	default:
		return -EINVAL;
	}

	val = i2c_smbus_read_word_swapped(i2c, reg);
	if (unlikely(val < 0))
		return val;

	switch (index) {
	case LTC2990_TEMP1:
	case LTC2990_TEMP2:
	case LTC2990_TEMP3:
		/* temp, 0.0625 degrees/LSB */
		*result = sign_extend32(val, 12) * 1000 / 16;
		break;
	case LTC2990_CURR1:
	case LTC2990_CURR2:
		 /* Vx-Vy, 19.42uV/LSB */
		*result = sign_extend32(val, 14) * 1942 / 100;
		break;
	case LTC2990_IN0:
		/* Vcc, 305.18uV/LSB, 2.5V offset */
		*result = sign_extend32(val, 14) * 30518 / (100 * 1000) + 2500;
		break;
	case LTC2990_IN1:
	case LTC2990_IN2:
	case LTC2990_IN3:
	case LTC2990_IN4:
		/* Vx, 305.18uV/LSB */
		*result = sign_extend32(val, 14) * 30518 / (100 * 1000);
		break;
	default:
		return -EINVAL; /* won't happen, keep compiler happy */
	}

	return 0;
}

static ssize_t ltc2990_value_show(struct device *dev,
				  struct device_attribute *da, char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	struct ltc2990_data *data = dev_get_drvdata(dev);
	int value;
	int ret;

	ret = ltc2990_get_value(data->i2c, attr->index, &value);
	if (unlikely(ret < 0))
		return ret;

	return snprintf(buf, PAGE_SIZE, "%d\n", value);
}

static umode_t ltc2990_attrs_visible(struct kobject *kobj,
				     struct attribute *a, int n)
{
	struct device *dev = container_of(kobj, struct device, kobj);
	struct ltc2990_data *data = dev_get_drvdata(dev);
	struct device_attribute *da =
			container_of(a, struct device_attribute, attr);
	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);

	int attrs_mask = LTC2990_IN0 | LTC2990_TEMP1 |
			 (ltc2990_attrs_ena_0[data->mode[0]] &
			  ltc2990_attrs_ena_1[data->mode[1]]);

	if (attr->index & attrs_mask)
		return a->mode;

	return 0;
}

static SENSOR_DEVICE_ATTR_RO(temp1_input, ltc2990_value, LTC2990_TEMP1);
static SENSOR_DEVICE_ATTR_RO(temp2_input, ltc2990_value, LTC2990_TEMP2);
static SENSOR_DEVICE_ATTR_RO(temp3_input, ltc2990_value, LTC2990_TEMP3);
static SENSOR_DEVICE_ATTR_RO(curr1_input, ltc2990_value, LTC2990_CURR1);
static SENSOR_DEVICE_ATTR_RO(curr2_input, ltc2990_value, LTC2990_CURR2);
static SENSOR_DEVICE_ATTR_RO(in0_input, ltc2990_value, LTC2990_IN0);
static SENSOR_DEVICE_ATTR_RO(in1_input, ltc2990_value, LTC2990_IN1);
static SENSOR_DEVICE_ATTR_RO(in2_input, ltc2990_value, LTC2990_IN2);
static SENSOR_DEVICE_ATTR_RO(in3_input, ltc2990_value, LTC2990_IN3);
static SENSOR_DEVICE_ATTR_RO(in4_input, ltc2990_value, LTC2990_IN4);

static struct attribute *ltc2990_attrs[] = {
	&sensor_dev_attr_temp1_input.dev_attr.attr,
	&sensor_dev_attr_temp2_input.dev_attr.attr,
	&sensor_dev_attr_temp3_input.dev_attr.attr,
	&sensor_dev_attr_curr1_input.dev_attr.attr,
	&sensor_dev_attr_curr2_input.dev_attr.attr,
	&sensor_dev_attr_in0_input.dev_attr.attr,
	&sensor_dev_attr_in1_input.dev_attr.attr,
	&sensor_dev_attr_in2_input.dev_attr.attr,
	&sensor_dev_attr_in3_input.dev_attr.attr,
	&sensor_dev_attr_in4_input.dev_attr.attr,
	NULL,
};

static const struct attribute_group ltc2990_group = {
	.attrs = ltc2990_attrs,
	.is_visible = ltc2990_attrs_visible,
};
__ATTRIBUTE_GROUPS(ltc2990);

static int ltc2990_i2c_probe(struct i2c_client *i2c,
			     const struct i2c_device_id *id)
{
	int ret;
	struct device *hwmon_dev;
	struct ltc2990_data *data;
	struct device_node *of_node = i2c->dev.of_node;

	if (!i2c_check_functionality(i2c->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
				     I2C_FUNC_SMBUS_WORD_DATA))
		return -ENODEV;

	data = devm_kzalloc(&i2c->dev, sizeof(struct ltc2990_data), GFP_KERNEL);
	if (unlikely(!data))
		return -ENOMEM;

	data->i2c = i2c;

	if (of_node) {
		ret = of_property_read_u32_array(of_node, "lltc,meas-mode",
						 data->mode, 2);
		if (ret < 0)
			return ret;

		if (data->mode[0] & ~LTC2990_MODE0_MASK ||
		    data->mode[1] & ~LTC2990_MODE1_MASK)
			return -EINVAL;
	} else {
		ret = i2c_smbus_read_byte_data(i2c, LTC2990_CONTROL);
		if (ret < 0)
			return ret;

		data->mode[0] = ret >> LTC2990_MODE0_SHIFT & LTC2990_MODE0_MASK;
		data->mode[1] = ret >> LTC2990_MODE1_SHIFT & LTC2990_MODE1_MASK;
	}

	/* Setup continuous mode */
	ret = i2c_smbus_write_byte_data(i2c, LTC2990_CONTROL,
					data->mode[0] << LTC2990_MODE0_SHIFT |
					data->mode[1] << LTC2990_MODE1_SHIFT);
	if (ret < 0) {
		dev_err(&i2c->dev, "Error: Failed to set control mode.\n");
		return ret;
	}
	/* Trigger once to start continuous conversion */
	ret = i2c_smbus_write_byte_data(i2c, LTC2990_TRIGGER, 1);
	if (ret < 0) {
		dev_err(&i2c->dev, "Error: Failed to start acquisition.\n");
		return ret;
	}

	hwmon_dev = devm_hwmon_device_register_with_groups(&i2c->dev,
							   i2c->name,
							   data,
							   ltc2990_groups);

	return PTR_ERR_OR_ZERO(hwmon_dev);
}

static const struct i2c_device_id ltc2990_i2c_id[] = {
	{ "ltc2990", 0 },
	{}
};
MODULE_DEVICE_TABLE(i2c, ltc2990_i2c_id);

static struct i2c_driver ltc2990_i2c_driver = {
	.driver = {
		.name = "ltc2990",
	},
	.probe    = ltc2990_i2c_probe,
	.id_table = ltc2990_i2c_id,
};

module_i2c_driver(ltc2990_i2c_driver);

MODULE_DESCRIPTION("LTC2990 Sensor Driver");
MODULE_AUTHOR("Topic Embedded Products");
MODULE_LICENSE("GPL v2");