xref: /openbmc/linux/drivers/hwmon/tmp103.c (revision 95777591)
1 /*
2  * Texas Instruments TMP103 SMBus temperature sensor driver
3  * Copyright (C) 2014 Heiko Schocher <hs@denx.de>
4  *
5  * Based on:
6  * Texas Instruments TMP102 SMBus temperature sensor driver
7  *
8  * Copyright (C) 2010 Steven King <sfking@fdwdc.com>
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of the GNU General Public License as published by
12  * the Free Software Foundation; either version 2 of the License, or
13  * (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18  * GNU General Public License for more details.
19  *
20  */
21 
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/slab.h>
25 #include <linux/i2c.h>
26 #include <linux/hwmon.h>
27 #include <linux/hwmon-sysfs.h>
28 #include <linux/err.h>
29 #include <linux/mutex.h>
30 #include <linux/device.h>
31 #include <linux/jiffies.h>
32 #include <linux/regmap.h>
33 
34 #define TMP103_TEMP_REG		0x00
35 #define TMP103_CONF_REG		0x01
36 #define TMP103_TLOW_REG		0x02
37 #define TMP103_THIGH_REG	0x03
38 
39 #define TMP103_CONF_M0		0x01
40 #define TMP103_CONF_M1		0x02
41 #define TMP103_CONF_LC		0x04
42 #define TMP103_CONF_FL		0x08
43 #define TMP103_CONF_FH		0x10
44 #define TMP103_CONF_CR0		0x20
45 #define TMP103_CONF_CR1		0x40
46 #define TMP103_CONF_ID		0x80
47 #define TMP103_CONF_SD		(TMP103_CONF_M1)
48 #define TMP103_CONF_SD_MASK	(TMP103_CONF_M0 | TMP103_CONF_M1)
49 
50 #define TMP103_CONFIG		(TMP103_CONF_CR1 | TMP103_CONF_M1)
51 #define TMP103_CONFIG_MASK	(TMP103_CONF_CR0 | TMP103_CONF_CR1 | \
52 				 TMP103_CONF_M0 | TMP103_CONF_M1)
53 
54 static inline int tmp103_reg_to_mc(s8 val)
55 {
56 	return val * 1000;
57 }
58 
59 static inline u8 tmp103_mc_to_reg(int val)
60 {
61 	return DIV_ROUND_CLOSEST(val, 1000);
62 }
63 
64 static ssize_t tmp103_temp_show(struct device *dev,
65 				struct device_attribute *attr, char *buf)
66 {
67 	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
68 	struct regmap *regmap = dev_get_drvdata(dev);
69 	unsigned int regval;
70 	int ret;
71 
72 	ret = regmap_read(regmap, sda->index, &regval);
73 	if (ret < 0)
74 		return ret;
75 
76 	return sprintf(buf, "%d\n", tmp103_reg_to_mc(regval));
77 }
78 
79 static ssize_t tmp103_temp_store(struct device *dev,
80 				 struct device_attribute *attr,
81 				 const char *buf, size_t count)
82 {
83 	struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
84 	struct regmap *regmap = dev_get_drvdata(dev);
85 	long val;
86 	int ret;
87 
88 	if (kstrtol(buf, 10, &val) < 0)
89 		return -EINVAL;
90 
91 	val = clamp_val(val, -55000, 127000);
92 	ret = regmap_write(regmap, sda->index, tmp103_mc_to_reg(val));
93 	return ret ? ret : count;
94 }
95 
96 static SENSOR_DEVICE_ATTR_RO(temp1_input, tmp103_temp, TMP103_TEMP_REG);
97 
98 static SENSOR_DEVICE_ATTR_RW(temp1_min, tmp103_temp, TMP103_TLOW_REG);
99 
100 static SENSOR_DEVICE_ATTR_RW(temp1_max, tmp103_temp, TMP103_THIGH_REG);
101 
102 static struct attribute *tmp103_attrs[] = {
103 	&sensor_dev_attr_temp1_input.dev_attr.attr,
104 	&sensor_dev_attr_temp1_min.dev_attr.attr,
105 	&sensor_dev_attr_temp1_max.dev_attr.attr,
106 	NULL
107 };
108 ATTRIBUTE_GROUPS(tmp103);
109 
110 static bool tmp103_regmap_is_volatile(struct device *dev, unsigned int reg)
111 {
112 	return reg == TMP103_TEMP_REG;
113 }
114 
115 static const struct regmap_config tmp103_regmap_config = {
116 	.reg_bits = 8,
117 	.val_bits = 8,
118 	.max_register = TMP103_THIGH_REG,
119 	.volatile_reg = tmp103_regmap_is_volatile,
120 };
121 
122 static int tmp103_probe(struct i2c_client *client,
123 			const struct i2c_device_id *id)
124 {
125 	struct device *dev = &client->dev;
126 	struct device *hwmon_dev;
127 	struct regmap *regmap;
128 	int ret;
129 
130 	regmap = devm_regmap_init_i2c(client, &tmp103_regmap_config);
131 	if (IS_ERR(regmap)) {
132 		dev_err(dev, "failed to allocate register map\n");
133 		return PTR_ERR(regmap);
134 	}
135 
136 	ret = regmap_update_bits(regmap, TMP103_CONF_REG, TMP103_CONFIG_MASK,
137 				 TMP103_CONFIG);
138 	if (ret < 0) {
139 		dev_err(&client->dev, "error writing config register\n");
140 		return ret;
141 	}
142 
143 	i2c_set_clientdata(client, regmap);
144 	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
145 						      regmap, tmp103_groups);
146 	return PTR_ERR_OR_ZERO(hwmon_dev);
147 }
148 
149 static int __maybe_unused tmp103_suspend(struct device *dev)
150 {
151 	struct regmap *regmap = dev_get_drvdata(dev);
152 
153 	return regmap_update_bits(regmap, TMP103_CONF_REG,
154 				  TMP103_CONF_SD_MASK, 0);
155 }
156 
157 static int __maybe_unused tmp103_resume(struct device *dev)
158 {
159 	struct regmap *regmap = dev_get_drvdata(dev);
160 
161 	return regmap_update_bits(regmap, TMP103_CONF_REG,
162 				  TMP103_CONF_SD_MASK, TMP103_CONF_SD);
163 }
164 
165 static SIMPLE_DEV_PM_OPS(tmp103_dev_pm_ops, tmp103_suspend, tmp103_resume);
166 
167 static const struct i2c_device_id tmp103_id[] = {
168 	{ "tmp103", 0 },
169 	{ }
170 };
171 MODULE_DEVICE_TABLE(i2c, tmp103_id);
172 
173 static const struct of_device_id tmp103_of_match[] = {
174 	{ .compatible = "ti,tmp103" },
175 	{ },
176 };
177 MODULE_DEVICE_TABLE(of, tmp103_of_match);
178 
179 static struct i2c_driver tmp103_driver = {
180 	.driver = {
181 		.name	= "tmp103",
182 		.of_match_table = of_match_ptr(tmp103_of_match),
183 		.pm	= &tmp103_dev_pm_ops,
184 	},
185 	.probe		= tmp103_probe,
186 	.id_table	= tmp103_id,
187 };
188 
189 module_i2c_driver(tmp103_driver);
190 
191 MODULE_AUTHOR("Heiko Schocher <hs@denx.de>");
192 MODULE_DESCRIPTION("Texas Instruments TMP103 temperature sensor driver");
193 MODULE_LICENSE("GPL");
194