drivers/iio/temperature/tmp006.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * tmp006.c - Support for TI TMP006 IR thermopile sensor
   4  *
   5  * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net>
   6  *
   7  * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor
   8  *
   9  * (7-bit I2C slave address 0x40, changeable via ADR pins)
  10  *
  11  * TODO: data ready irq
  12  */
  13
  14 #include <linux/err.h>
  15 #include <linux/i2c.h>
  16 #include <linux/delay.h>
  17 #include <linux/module.h>
  18 #include <linux/mod_devicetable.h>
  19 #include <linux/pm.h>
  20 #include <linux/bitops.h>
  21
  22 #include <linux/iio/iio.h>
  23 #include <linux/iio/sysfs.h>
  24
  25 #define TMP006_VOBJECT 0x00
  26 #define TMP006_TAMBIENT 0x01
  27 #define TMP006_CONFIG 0x02
  28 #define TMP006_MANUFACTURER_ID 0xfe
  29 #define TMP006_DEVICE_ID 0xff
  30
  31 #define TMP006_TAMBIENT_SHIFT 2
  32
  33 #define TMP006_CONFIG_RESET BIT(15)
  34 #define TMP006_CONFIG_DRDY_EN BIT(8)
  35 #define TMP006_CONFIG_DRDY BIT(7)
  36
  37 #define TMP006_CONFIG_MOD_MASK GENMASK(14, 12)
  38
  39 #define TMP006_CONFIG_CR_MASK GENMASK(11, 9)
  40 #define TMP006_CONFIG_CR_SHIFT 9
  41
  42 #define TMP006_MANUFACTURER_MAGIC 0x5449
  43 #define TMP006_DEVICE_MAGIC 0x0067
  44
  45 struct tmp006_data {
  46         struct i2c_client *client;
  47         u16 config;
  48 };
  49
  50 static int tmp006_read_measurement(struct tmp006_data *data, u8 reg)
  51 {
  52         s32 ret;
  53         int tries = 50;
  54
  55         while (tries-- > 0) {
  56                 ret = i2c_smbus_read_word_swapped(data->client,
  57                         TMP006_CONFIG);
  58                 if (ret < 0)
  59                         return ret;
  60                 if (ret & TMP006_CONFIG_DRDY)
  61                         break;
  62                 msleep(100);
  63         }
  64
  65         if (tries < 0)
  66                 return -EIO;
  67
  68         return i2c_smbus_read_word_swapped(data->client, reg);
  69 }
  70
  71 static const int tmp006_freqs[5][2] = { {4, 0}, {2, 0}, {1, 0},
  72                                         {0, 500000}, {0, 250000} };
  73
  74 static int tmp006_read_raw(struct iio_dev *indio_dev,
  75                             struct iio_chan_spec const *channel, int *val,
  76                             int *val2, long mask)
  77 {
  78         struct tmp006_data *data = iio_priv(indio_dev);
  79         s32 ret;
  80         int cr;
  81
  82         switch (mask) {
  83         case IIO_CHAN_INFO_RAW:
  84                 if (channel->type == IIO_VOLTAGE) {
  85                         /* LSB is 156.25 nV */
  86                         ret = tmp006_read_measurement(data, TMP006_VOBJECT);
  87                         if (ret < 0)
  88                                 return ret;
  89                         *val = sign_extend32(ret, 15);
  90                 } else if (channel->type == IIO_TEMP) {
  91                         /* LSB is 0.03125 degrees Celsius */
  92                         ret = tmp006_read_measurement(data, TMP006_TAMBIENT);
  93                         if (ret < 0)
  94                                 return ret;
  95                         *val = sign_extend32(ret, 15) >> TMP006_TAMBIENT_SHIFT;
  96                 } else {
  97                         break;
  98                 }
  99                 return IIO_VAL_INT;
 100         case IIO_CHAN_INFO_SCALE:
 101                 if (channel->type == IIO_VOLTAGE) {
 102                         *val = 0;
 103                         *val2 = 156250;
 104                 } else if (channel->type == IIO_TEMP) {
 105                         *val = 31;
 106                         *val2 = 250000;
 107                 } else {
 108                         break;
 109                 }
 110                 return IIO_VAL_INT_PLUS_MICRO;
 111         case IIO_CHAN_INFO_SAMP_FREQ:
 112                 cr = (data->config & TMP006_CONFIG_CR_MASK)
 113                         >> TMP006_CONFIG_CR_SHIFT;
 114                 *val = tmp006_freqs[cr][0];
 115                 *val2 = tmp006_freqs[cr][1];
 116                 return IIO_VAL_INT_PLUS_MICRO;
 117         default:
 118                 break;
 119         }
 120
 121         return -EINVAL;
 122 }
 123
 124 static int tmp006_write_raw(struct iio_dev *indio_dev,
 125                             struct iio_chan_spec const *chan,
 126                             int val,
 127                             int val2,
 128                             long mask)
 129 {
 130         struct tmp006_data *data = iio_priv(indio_dev);
 131         int i;
 132
 133         if (mask != IIO_CHAN_INFO_SAMP_FREQ)
 134                 return -EINVAL;
 135
 136         for (i = 0; i < ARRAY_SIZE(tmp006_freqs); i++)
 137                 if ((val == tmp006_freqs[i][0]) &&
 138                     (val2 == tmp006_freqs[i][1])) {
 139                         data->config &= ~TMP006_CONFIG_CR_MASK;
 140                         data->config |= i << TMP006_CONFIG_CR_SHIFT;
 141
 142                         return i2c_smbus_write_word_swapped(data->client,
 143                                                             TMP006_CONFIG,
 144                                                             data->config);
 145
 146                 }
 147         return -EINVAL;
 148 }
 149
 150 static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25");
 151
 152 static struct attribute *tmp006_attributes[] = {
 153         &iio_const_attr_sampling_frequency_available.dev_attr.attr,
 154         NULL
 155 };
 156
 157 static const struct attribute_group tmp006_attribute_group = {
 158         .attrs = tmp006_attributes,
 159 };
 160
 161 static const struct iio_chan_spec tmp006_channels[] = {
 162         {
 163                 .type = IIO_VOLTAGE,
 164                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 165                         BIT(IIO_CHAN_INFO_SCALE),
 166                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 167         },
 168         {
 169                 .type = IIO_TEMP,
 170                 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
 171                         BIT(IIO_CHAN_INFO_SCALE),
 172                 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
 173         }
 174 };
 175
 176 static const struct iio_info tmp006_info = {
 177         .read_raw = tmp006_read_raw,
 178         .write_raw = tmp006_write_raw,
 179         .attrs = &tmp006_attribute_group,
 180 };
 181
 182 static bool tmp006_check_identification(struct i2c_client *client)
 183 {
 184         int mid, did;
 185
 186         mid = i2c_smbus_read_word_swapped(client, TMP006_MANUFACTURER_ID);
 187         if (mid < 0)
 188                 return false;
 189
 190         did = i2c_smbus_read_word_swapped(client, TMP006_DEVICE_ID);
 191         if (did < 0)
 192                 return false;
 193
 194         return mid == TMP006_MANUFACTURER_MAGIC && did == TMP006_DEVICE_MAGIC;
 195 }
 196
 197 static int tmp006_power(struct device *dev, bool up)
 198 {
 199         struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
 200         struct tmp006_data *data = iio_priv(indio_dev);
 201
 202         if (up)
 203                 data->config |= TMP006_CONFIG_MOD_MASK;
 204         else
 205                 data->config &= ~TMP006_CONFIG_MOD_MASK;
 206
 207         return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG,
 208                 data->config);
 209 }
 210
 211 static void tmp006_powerdown_cleanup(void *dev)
 212 {
 213         tmp006_power(dev, false);
 214 }
 215
 216 static int tmp006_probe(struct i2c_client *client)
 217 {
 218         struct iio_dev *indio_dev;
 219         struct tmp006_data *data;
 220         int ret;
 221
 222         if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA))
 223                 return -EOPNOTSUPP;
 224
 225         if (!tmp006_check_identification(client)) {
 226                 dev_err(&client->dev, "no TMP006 sensor\n");
 227                 return -ENODEV;
 228         }
 229
 230         indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
 231         if (!indio_dev)
 232                 return -ENOMEM;
 233
 234         data = iio_priv(indio_dev);
 235         i2c_set_clientdata(client, indio_dev);
 236         data->client = client;
 237
 238         indio_dev->name = dev_name(&client->dev);
 239         indio_dev->modes = INDIO_DIRECT_MODE;
 240         indio_dev->info = &tmp006_info;
 241
 242         indio_dev->channels = tmp006_channels;
 243         indio_dev->num_channels = ARRAY_SIZE(tmp006_channels);
 244
 245         ret = i2c_smbus_read_word_swapped(data->client, TMP006_CONFIG);
 246         if (ret < 0)
 247                 return ret;
 248         data->config = ret;
 249
 250         if ((ret & TMP006_CONFIG_MOD_MASK) != TMP006_CONFIG_MOD_MASK) {
 251                 ret = tmp006_power(&client->dev, true);
 252                 if (ret < 0)
 253                         return ret;
 254         }
 255
 256         ret = devm_add_action_or_reset(&client->dev, tmp006_powerdown_cleanup,
 257                                        &client->dev);
 258         if (ret < 0)
 259                 return ret;
 260
 261         return devm_iio_device_register(&client->dev, indio_dev);
 262 }
 263
 264 static int tmp006_suspend(struct device *dev)
 265 {
 266         return tmp006_power(dev, false);
 267 }
 268
 269 static int tmp006_resume(struct device *dev)
 270 {
 271         return tmp006_power(dev, true);
 272 }
 273
 274 static DEFINE_SIMPLE_DEV_PM_OPS(tmp006_pm_ops, tmp006_suspend, tmp006_resume);
 275
 276 static const struct of_device_id tmp006_of_match[] = {
 277         { .compatible = "ti,tmp006" },
 278         { }
 279 };
 280 MODULE_DEVICE_TABLE(of, tmp006_of_match);
 281
 282 static const struct i2c_device_id tmp006_id[] = {
 283         { "tmp006", 0 },
 284         { }
 285 };
 286 MODULE_DEVICE_TABLE(i2c, tmp006_id);
 287
 288 static struct i2c_driver tmp006_driver = {
 289         .driver = {
 290                 .name   = "tmp006",
 291                 .of_match_table = tmp006_of_match,
 292                 .pm     = pm_sleep_ptr(&tmp006_pm_ops),
 293         },
 294         .probe = tmp006_probe,
 295         .id_table = tmp006_id,
 296 };
 297 module_i2c_driver(tmp006_driver);
 298
 299 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 300 MODULE_DESCRIPTION("TI TMP006 IR thermopile sensor driver");
 301 MODULE_LICENSE("GPL");