tmp103.c

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