drivers/hwmon/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/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 ssize_t tmp103_temp_show(struct device *dev,
  55                                 struct device_attribute *attr, char *buf)
  56 {
  57         struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
  58         struct regmap *regmap = dev_get_drvdata(dev);
  59         unsigned int regval;
  60         int ret;
  61
  62         ret = regmap_read(regmap, sda->index, &regval);
  63         if (ret < 0)
  64                 return ret;
  65
  66         return sprintf(buf, "%d\n", tmp103_reg_to_mc(regval));
  67 }
  68
  69 static ssize_t tmp103_temp_store(struct device *dev,
  70                                  struct device_attribute *attr,
  71                                  const char *buf, size_t count)
  72 {
  73         struct sensor_device_attribute *sda = to_sensor_dev_attr(attr);
  74         struct regmap *regmap = dev_get_drvdata(dev);
  75         long val;
  76         int ret;
  77
  78         if (kstrtol(buf, 10, &val) < 0)
  79                 return -EINVAL;
  80
  81         val = clamp_val(val, -55000, 127000);
  82         ret = regmap_write(regmap, sda->index, tmp103_mc_to_reg(val));
  83         return ret ? ret : count;
  84 }
  85
  86 static SENSOR_DEVICE_ATTR_RO(temp1_input, tmp103_temp, TMP103_TEMP_REG);
  87
  88 static SENSOR_DEVICE_ATTR_RW(temp1_min, tmp103_temp, TMP103_TLOW_REG);
  89
  90 static SENSOR_DEVICE_ATTR_RW(temp1_max, tmp103_temp, TMP103_THIGH_REG);
  91
  92 static struct attribute *tmp103_attrs[] = {
  93         &sensor_dev_attr_temp1_input.dev_attr.attr,
  94         &sensor_dev_attr_temp1_min.dev_attr.attr,
  95         &sensor_dev_attr_temp1_max.dev_attr.attr,
  96         NULL
  97 };
  98 ATTRIBUTE_GROUPS(tmp103);
  99
 100 static bool tmp103_regmap_is_volatile(struct device *dev, unsigned int reg)
 101 {
 102         return reg == TMP103_TEMP_REG;
 103 }
 104
 105 static const struct regmap_config tmp103_regmap_config = {
 106         .reg_bits = 8,
 107         .val_bits = 8,
 108         .max_register = TMP103_THIGH_REG,
 109         .volatile_reg = tmp103_regmap_is_volatile,
 110 };
 111
 112 static int tmp103_probe(struct i2c_client *client)
 113 {
 114         struct device *dev = &client->dev;
 115         struct device *hwmon_dev;
 116         struct regmap *regmap;
 117         int ret;
 118
 119         regmap = devm_regmap_init_i2c(client, &tmp103_regmap_config);
 120         if (IS_ERR(regmap)) {
 121                 dev_err(dev, "failed to allocate register map\n");
 122                 return PTR_ERR(regmap);
 123         }
 124
 125         ret = regmap_update_bits(regmap, TMP103_CONF_REG, TMP103_CONFIG_MASK,
 126                                  TMP103_CONFIG);
 127         if (ret < 0) {
 128                 dev_err(&client->dev, "error writing config register\n");
 129                 return ret;
 130         }
 131
 132         i2c_set_clientdata(client, regmap);
 133         hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
 134                                                       regmap, tmp103_groups);
 135         return PTR_ERR_OR_ZERO(hwmon_dev);
 136 }
 137
 138 static int __maybe_unused tmp103_suspend(struct device *dev)
 139 {
 140         struct regmap *regmap = dev_get_drvdata(dev);
 141
 142         return regmap_update_bits(regmap, TMP103_CONF_REG,
 143                                   TMP103_CONF_SD_MASK, 0);
 144 }
 145
 146 static int __maybe_unused tmp103_resume(struct device *dev)
 147 {
 148         struct regmap *regmap = dev_get_drvdata(dev);
 149
 150         return regmap_update_bits(regmap, TMP103_CONF_REG,
 151                                   TMP103_CONF_SD_MASK, TMP103_CONF_SD);
 152 }
 153
 154 static SIMPLE_DEV_PM_OPS(tmp103_dev_pm_ops, tmp103_suspend, tmp103_resume);
 155
 156 static const struct i2c_device_id tmp103_id[] = {
 157         { "tmp103", 0 },
 158         { }
 159 };
 160 MODULE_DEVICE_TABLE(i2c, tmp103_id);
 161
 162 static const struct of_device_id __maybe_unused tmp103_of_match[] = {
 163         { .compatible = "ti,tmp103" },
 164         { },
 165 };
 166 MODULE_DEVICE_TABLE(of, tmp103_of_match);
 167
 168 static struct i2c_driver tmp103_driver = {
 169         .driver = {
 170                 .name   = "tmp103",
 171                 .of_match_table = of_match_ptr(tmp103_of_match),
 172                 .pm     = &tmp103_dev_pm_ops,
 173         },
 174         .probe_new      = tmp103_probe,
 175         .id_table       = tmp103_id,
 176 };
 177
 178 module_i2c_driver(tmp103_driver);
 179
 180 MODULE_AUTHOR("Heiko Schocher <hs@denx.de>");
 181 MODULE_DESCRIPTION("Texas Instruments TMP103 temperature sensor driver");
 182 MODULE_LICENSE("GPL");