xref: /openbmc/linux/drivers/hwmon/tmp103.c (revision e65e175b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Texas Instruments TMP103 SMBus temperature sensor driver
4  * Copyright (C) 2014 Heiko Schocher <hs@denx.de>
5  *
6  * Based on:
7  * Texas Instruments TMP102 SMBus temperature sensor driver
8  *
9  * Copyright (C) 2010 Steven King <sfking@fdwdc.com>
10  */
11 
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/slab.h>
15 #include <linux/i2c.h>
16 #include <linux/hwmon.h>
17 #include <linux/hwmon-sysfs.h>
18 #include <linux/err.h>
19 #include <linux/mutex.h>
20 #include <linux/device.h>
21 #include <linux/jiffies.h>
22 #include <linux/regmap.h>
23 
24 #define TMP103_TEMP_REG		0x00
25 #define TMP103_CONF_REG		0x01
26 #define TMP103_TLOW_REG		0x02
27 #define TMP103_THIGH_REG	0x03
28 
29 #define TMP103_CONF_M0		0x01
30 #define TMP103_CONF_M1		0x02
31 #define TMP103_CONF_LC		0x04
32 #define TMP103_CONF_FL		0x08
33 #define TMP103_CONF_FH		0x10
34 #define TMP103_CONF_CR0		0x20
35 #define TMP103_CONF_CR1		0x40
36 #define TMP103_CONF_ID		0x80
37 #define TMP103_CONF_SD		(TMP103_CONF_M1)
38 #define TMP103_CONF_SD_MASK	(TMP103_CONF_M0 | TMP103_CONF_M1)
39 
40 #define TMP103_CONFIG		(TMP103_CONF_CR1 | TMP103_CONF_M1)
41 #define TMP103_CONFIG_MASK	(TMP103_CONF_CR0 | TMP103_CONF_CR1 | \
42 				 TMP103_CONF_M0 | TMP103_CONF_M1)
43 
44 static inline int tmp103_reg_to_mc(s8 val)
45 {
46 	return val * 1000;
47 }
48 
49 static inline u8 tmp103_mc_to_reg(int val)
50 {
51 	return DIV_ROUND_CLOSEST(val, 1000);
52 }
53 
54 static int tmp103_read(struct device *dev, enum hwmon_sensor_types type,
55 		       u32 attr, int channel, long *temp)
56 {
57 	struct regmap *regmap = dev_get_drvdata(dev);
58 	unsigned int regval;
59 	int err, reg;
60 
61 	switch (attr) {
62 	case hwmon_temp_input:
63 		reg = TMP103_TEMP_REG;
64 		break;
65 	case hwmon_temp_min:
66 		reg = TMP103_TLOW_REG;
67 		break;
68 	case hwmon_temp_max:
69 		reg = TMP103_THIGH_REG;
70 		break;
71 	default:
72 		return -EOPNOTSUPP;
73 	}
74 
75 	err = regmap_read(regmap, reg, &regval);
76 	if (err < 0)
77 		return err;
78 
79 	*temp = tmp103_reg_to_mc(regval);
80 
81 	return 0;
82 }
83 
84 static int tmp103_write(struct device *dev, enum hwmon_sensor_types type,
85 			u32 attr, int channel, long temp)
86 {
87 	struct regmap *regmap = dev_get_drvdata(dev);
88 	int reg;
89 
90 	switch (attr) {
91 	case hwmon_temp_min:
92 		reg = TMP103_TLOW_REG;
93 		break;
94 	case hwmon_temp_max:
95 		reg = TMP103_THIGH_REG;
96 		break;
97 	default:
98 		return -EOPNOTSUPP;
99 	}
100 
101 	temp = clamp_val(temp, -55000, 127000);
102 	return regmap_write(regmap, reg, tmp103_mc_to_reg(temp));
103 }
104 
105 static umode_t tmp103_is_visible(const void *data, enum hwmon_sensor_types type,
106 				 u32 attr, int channel)
107 {
108 	if (type != hwmon_temp)
109 		return 0;
110 
111 	switch (attr) {
112 	case hwmon_temp_input:
113 		return 0444;
114 	case hwmon_temp_min:
115 	case hwmon_temp_max:
116 		return 0644;
117 	default:
118 		return 0;
119 	}
120 }
121 
122 static const struct hwmon_channel_info *tmp103_info[] = {
123 	HWMON_CHANNEL_INFO(chip,
124 			   HWMON_C_REGISTER_TZ),
125 	HWMON_CHANNEL_INFO(temp,
126 			   HWMON_T_INPUT | HWMON_T_MAX | HWMON_T_MIN),
127 	NULL
128 };
129 
130 static const struct hwmon_ops tmp103_hwmon_ops = {
131 	.is_visible = tmp103_is_visible,
132 	.read = tmp103_read,
133 	.write = tmp103_write,
134 };
135 
136 static const struct hwmon_chip_info tmp103_chip_info = {
137 	.ops = &tmp103_hwmon_ops,
138 	.info = tmp103_info,
139 };
140 
141 static bool tmp103_regmap_is_volatile(struct device *dev, unsigned int reg)
142 {
143 	return reg == TMP103_TEMP_REG;
144 }
145 
146 static const struct regmap_config tmp103_regmap_config = {
147 	.reg_bits = 8,
148 	.val_bits = 8,
149 	.max_register = TMP103_THIGH_REG,
150 	.volatile_reg = tmp103_regmap_is_volatile,
151 };
152 
153 static int tmp103_probe(struct i2c_client *client)
154 {
155 	struct device *dev = &client->dev;
156 	struct device *hwmon_dev;
157 	struct regmap *regmap;
158 	int ret;
159 
160 	regmap = devm_regmap_init_i2c(client, &tmp103_regmap_config);
161 	if (IS_ERR(regmap)) {
162 		dev_err(dev, "failed to allocate register map\n");
163 		return PTR_ERR(regmap);
164 	}
165 
166 	ret = regmap_update_bits(regmap, TMP103_CONF_REG, TMP103_CONFIG_MASK,
167 				 TMP103_CONFIG);
168 	if (ret < 0) {
169 		dev_err(&client->dev, "error writing config register\n");
170 		return ret;
171 	}
172 
173 	i2c_set_clientdata(client, regmap);
174 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
175 							 regmap,
176 							 &tmp103_chip_info,
177 							 NULL);
178 	return PTR_ERR_OR_ZERO(hwmon_dev);
179 }
180 
181 static int tmp103_suspend(struct device *dev)
182 {
183 	struct regmap *regmap = dev_get_drvdata(dev);
184 
185 	return regmap_update_bits(regmap, TMP103_CONF_REG,
186 				  TMP103_CONF_SD_MASK, 0);
187 }
188 
189 static int tmp103_resume(struct device *dev)
190 {
191 	struct regmap *regmap = dev_get_drvdata(dev);
192 
193 	return regmap_update_bits(regmap, TMP103_CONF_REG,
194 				  TMP103_CONF_SD_MASK, TMP103_CONF_SD);
195 }
196 
197 static DEFINE_SIMPLE_DEV_PM_OPS(tmp103_dev_pm_ops, tmp103_suspend, tmp103_resume);
198 
199 static const struct i2c_device_id tmp103_id[] = {
200 	{ "tmp103", 0 },
201 	{ }
202 };
203 MODULE_DEVICE_TABLE(i2c, tmp103_id);
204 
205 static const struct of_device_id __maybe_unused tmp103_of_match[] = {
206 	{ .compatible = "ti,tmp103" },
207 	{ },
208 };
209 MODULE_DEVICE_TABLE(of, tmp103_of_match);
210 
211 static struct i2c_driver tmp103_driver = {
212 	.driver = {
213 		.name	= "tmp103",
214 		.of_match_table = of_match_ptr(tmp103_of_match),
215 		.pm	= pm_sleep_ptr(&tmp103_dev_pm_ops),
216 	},
217 	.probe_new	= tmp103_probe,
218 	.id_table	= tmp103_id,
219 };
220 
221 module_i2c_driver(tmp103_driver);
222 
223 MODULE_AUTHOR("Heiko Schocher <hs@denx.de>");
224 MODULE_DESCRIPTION("Texas Instruments TMP103 temperature sensor driver");
225 MODULE_LICENSE("GPL");
226