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 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 * const 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" },
 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          = 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");