1 /* 2 * tmp006.c - Support for TI TMP006 IR thermopile sensor 3 * 4 * Copyright (c) 2013 Peter Meerwald <pmeerw@pmeerw.net> 5 * 6 * This file is subject to the terms and conditions of version 2 of 7 * the GNU General Public License. See the file COPYING in the main 8 * directory of this archive for more details. 9 * 10 * Driver for the Texas Instruments I2C 16-bit IR thermopile sensor 11 * 12 * (7-bit I2C slave address 0x40, changeable via ADR pins) 13 * 14 * TODO: data ready irq 15 */ 16 17 #include <linux/err.h> 18 #include <linux/i2c.h> 19 #include <linux/delay.h> 20 #include <linux/module.h> 21 #include <linux/pm.h> 22 #include <linux/bitops.h> 23 24 #include <linux/iio/iio.h> 25 #include <linux/iio/sysfs.h> 26 27 #define TMP006_VOBJECT 0x00 28 #define TMP006_TAMBIENT 0x01 29 #define TMP006_CONFIG 0x02 30 #define TMP006_MANUFACTURER_ID 0xfe 31 #define TMP006_DEVICE_ID 0xff 32 33 #define TMP006_TAMBIENT_SHIFT 2 34 35 #define TMP006_CONFIG_RESET BIT(15) 36 #define TMP006_CONFIG_DRDY_EN BIT(8) 37 #define TMP006_CONFIG_DRDY BIT(7) 38 39 #define TMP006_CONFIG_MOD_MASK GENMASK(14, 12) 40 41 #define TMP006_CONFIG_CR_MASK GENMASK(11, 9) 42 #define TMP006_CONFIG_CR_SHIFT 9 43 44 #define TMP006_MANUFACTURER_MAGIC 0x5449 45 #define TMP006_DEVICE_MAGIC 0x0067 46 47 struct tmp006_data { 48 struct i2c_client *client; 49 u16 config; 50 }; 51 52 static int tmp006_read_measurement(struct tmp006_data *data, u8 reg) 53 { 54 s32 ret; 55 int tries = 50; 56 57 while (tries-- > 0) { 58 ret = i2c_smbus_read_word_swapped(data->client, 59 TMP006_CONFIG); 60 if (ret < 0) 61 return ret; 62 if (ret & TMP006_CONFIG_DRDY) 63 break; 64 msleep(100); 65 } 66 67 if (tries < 0) 68 return -EIO; 69 70 return i2c_smbus_read_word_swapped(data->client, reg); 71 } 72 73 static const int tmp006_freqs[5][2] = { {4, 0}, {2, 0}, {1, 0}, 74 {0, 500000}, {0, 250000} }; 75 76 static int tmp006_read_raw(struct iio_dev *indio_dev, 77 struct iio_chan_spec const *channel, int *val, 78 int *val2, long mask) 79 { 80 struct tmp006_data *data = iio_priv(indio_dev); 81 s32 ret; 82 int cr; 83 84 switch (mask) { 85 case IIO_CHAN_INFO_RAW: 86 if (channel->type == IIO_VOLTAGE) { 87 /* LSB is 156.25 nV */ 88 ret = tmp006_read_measurement(data, TMP006_VOBJECT); 89 if (ret < 0) 90 return ret; 91 *val = sign_extend32(ret, 15); 92 } else if (channel->type == IIO_TEMP) { 93 /* LSB is 0.03125 degrees Celsius */ 94 ret = tmp006_read_measurement(data, TMP006_TAMBIENT); 95 if (ret < 0) 96 return ret; 97 *val = sign_extend32(ret, 15) >> TMP006_TAMBIENT_SHIFT; 98 } else { 99 break; 100 } 101 return IIO_VAL_INT; 102 case IIO_CHAN_INFO_SCALE: 103 if (channel->type == IIO_VOLTAGE) { 104 *val = 0; 105 *val2 = 156250; 106 } else if (channel->type == IIO_TEMP) { 107 *val = 31; 108 *val2 = 250000; 109 } else { 110 break; 111 } 112 return IIO_VAL_INT_PLUS_MICRO; 113 case IIO_CHAN_INFO_SAMP_FREQ: 114 cr = (data->config & TMP006_CONFIG_CR_MASK) 115 >> TMP006_CONFIG_CR_SHIFT; 116 *val = tmp006_freqs[cr][0]; 117 *val2 = tmp006_freqs[cr][1]; 118 return IIO_VAL_INT_PLUS_MICRO; 119 default: 120 break; 121 } 122 123 return -EINVAL; 124 } 125 126 static int tmp006_write_raw(struct iio_dev *indio_dev, 127 struct iio_chan_spec const *chan, 128 int val, 129 int val2, 130 long mask) 131 { 132 struct tmp006_data *data = iio_priv(indio_dev); 133 int i; 134 135 if (mask != IIO_CHAN_INFO_SAMP_FREQ) 136 return -EINVAL; 137 138 for (i = 0; i < ARRAY_SIZE(tmp006_freqs); i++) 139 if ((val == tmp006_freqs[i][0]) && 140 (val2 == tmp006_freqs[i][1])) { 141 data->config &= ~TMP006_CONFIG_CR_MASK; 142 data->config |= i << TMP006_CONFIG_CR_SHIFT; 143 144 return i2c_smbus_write_word_swapped(data->client, 145 TMP006_CONFIG, 146 data->config); 147 148 } 149 return -EINVAL; 150 } 151 152 static IIO_CONST_ATTR(sampling_frequency_available, "4 2 1 0.5 0.25"); 153 154 static struct attribute *tmp006_attributes[] = { 155 &iio_const_attr_sampling_frequency_available.dev_attr.attr, 156 NULL 157 }; 158 159 static const struct attribute_group tmp006_attribute_group = { 160 .attrs = tmp006_attributes, 161 }; 162 163 static const struct iio_chan_spec tmp006_channels[] = { 164 { 165 .type = IIO_VOLTAGE, 166 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 167 BIT(IIO_CHAN_INFO_SCALE), 168 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), 169 }, 170 { 171 .type = IIO_TEMP, 172 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | 173 BIT(IIO_CHAN_INFO_SCALE), 174 .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ), 175 } 176 }; 177 178 static const struct iio_info tmp006_info = { 179 .read_raw = tmp006_read_raw, 180 .write_raw = tmp006_write_raw, 181 .attrs = &tmp006_attribute_group, 182 .driver_module = THIS_MODULE, 183 }; 184 185 static bool tmp006_check_identification(struct i2c_client *client) 186 { 187 int mid, did; 188 189 mid = i2c_smbus_read_word_swapped(client, TMP006_MANUFACTURER_ID); 190 if (mid < 0) 191 return false; 192 193 did = i2c_smbus_read_word_swapped(client, TMP006_DEVICE_ID); 194 if (did < 0) 195 return false; 196 197 return mid == TMP006_MANUFACTURER_MAGIC && did == TMP006_DEVICE_MAGIC; 198 } 199 200 static int tmp006_probe(struct i2c_client *client, 201 const struct i2c_device_id *id) 202 { 203 struct iio_dev *indio_dev; 204 struct tmp006_data *data; 205 int ret; 206 207 if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) 208 return -EOPNOTSUPP; 209 210 if (!tmp006_check_identification(client)) { 211 dev_err(&client->dev, "no TMP006 sensor\n"); 212 return -ENODEV; 213 } 214 215 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); 216 if (!indio_dev) 217 return -ENOMEM; 218 219 data = iio_priv(indio_dev); 220 i2c_set_clientdata(client, indio_dev); 221 data->client = client; 222 223 indio_dev->dev.parent = &client->dev; 224 indio_dev->name = dev_name(&client->dev); 225 indio_dev->modes = INDIO_DIRECT_MODE; 226 indio_dev->info = &tmp006_info; 227 228 indio_dev->channels = tmp006_channels; 229 indio_dev->num_channels = ARRAY_SIZE(tmp006_channels); 230 231 ret = i2c_smbus_read_word_swapped(data->client, TMP006_CONFIG); 232 if (ret < 0) 233 return ret; 234 data->config = ret; 235 236 return iio_device_register(indio_dev); 237 } 238 239 static int tmp006_powerdown(struct tmp006_data *data) 240 { 241 return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG, 242 data->config & ~TMP006_CONFIG_MOD_MASK); 243 } 244 245 static int tmp006_remove(struct i2c_client *client) 246 { 247 struct iio_dev *indio_dev = i2c_get_clientdata(client); 248 249 iio_device_unregister(indio_dev); 250 tmp006_powerdown(iio_priv(indio_dev)); 251 252 return 0; 253 } 254 255 #ifdef CONFIG_PM_SLEEP 256 static int tmp006_suspend(struct device *dev) 257 { 258 struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); 259 return tmp006_powerdown(iio_priv(indio_dev)); 260 } 261 262 static int tmp006_resume(struct device *dev) 263 { 264 struct tmp006_data *data = iio_priv(i2c_get_clientdata( 265 to_i2c_client(dev))); 266 return i2c_smbus_write_word_swapped(data->client, TMP006_CONFIG, 267 data->config | TMP006_CONFIG_MOD_MASK); 268 } 269 #endif 270 271 static SIMPLE_DEV_PM_OPS(tmp006_pm_ops, tmp006_suspend, tmp006_resume); 272 273 static const struct i2c_device_id tmp006_id[] = { 274 { "tmp006", 0 }, 275 { } 276 }; 277 MODULE_DEVICE_TABLE(i2c, tmp006_id); 278 279 static struct i2c_driver tmp006_driver = { 280 .driver = { 281 .name = "tmp006", 282 .pm = &tmp006_pm_ops, 283 }, 284 .probe = tmp006_probe, 285 .remove = tmp006_remove, 286 .id_table = tmp006_id, 287 }; 288 module_i2c_driver(tmp006_driver); 289 290 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>"); 291 MODULE_DESCRIPTION("TI TMP006 IR thermopile sensor driver"); 292 MODULE_LICENSE("GPL"); 293