drivers/iio/chemical/bme680_i2c.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * BME680 - I2C Driver
   4  *
   5  * Copyright (C) 2018 Himanshu Jha <himanshujha199640@gmail.com>
   6  *
   7  * 7-Bit I2C slave address is:
   8  *      - 0x76 if SDO is pulled to GND
   9  *      - 0x77 if SDO is pulled to VDDIO
  10  *
  11  * Note: SDO pin cannot be left floating otherwise I2C address
  12  *       will be undefined.
  13  */
  14 #include <linux/acpi.h>
  15 #include <linux/i2c.h>
  16 #include <linux/module.h>
  17 #include <linux/regmap.h>
  18
  19 #include "bme680.h"
  20
  21 static int bme680_i2c_probe(struct i2c_client *client,
  22                             const struct i2c_device_id *id)
  23 {
  24         struct regmap *regmap;
  25         const char *name = NULL;
  26         unsigned int val;
  27         int ret;
  28
  29         regmap = devm_regmap_init_i2c(client, &bme680_regmap_config);
  30         if (IS_ERR(regmap)) {
  31                 dev_err(&client->dev, "Failed to register i2c regmap %d\n",
  32                                 (int)PTR_ERR(regmap));
  33                 return PTR_ERR(regmap);
  34         }
  35
  36         ret = regmap_write(regmap, BME680_REG_SOFT_RESET_I2C,
  37                            BME680_CMD_SOFTRESET);
  38         if (ret < 0) {
  39                 dev_err(&client->dev, "Failed to reset chip\n");
  40                 return ret;
  41         }
  42
  43         ret = regmap_read(regmap, BME680_REG_CHIP_I2C_ID, &val);
  44         if (ret < 0) {
  45                 dev_err(&client->dev, "Error reading I2C chip ID\n");
  46                 return ret;
  47         }
  48
  49         if (val != BME680_CHIP_ID_VAL) {
  50                 dev_err(&client->dev, "Wrong chip ID, got %x expected %x\n",
  51                                 val, BME680_CHIP_ID_VAL);
  52                 return -ENODEV;
  53         }
  54
  55         if (id)
  56                 name = id->name;
  57
  58         return bme680_core_probe(&client->dev, regmap, name);
  59 }
  60
  61 static const struct i2c_device_id bme680_i2c_id[] = {
  62         {"bme680", 0},
  63         {},
  64 };
  65 MODULE_DEVICE_TABLE(i2c, bme680_i2c_id);
  66
  67 static const struct acpi_device_id bme680_acpi_match[] = {
  68         {"BME0680", 0},
  69         {},
  70 };
  71 MODULE_DEVICE_TABLE(acpi, bme680_acpi_match);
  72
  73 static struct i2c_driver bme680_i2c_driver = {
  74         .driver = {
  75                 .name                   = "bme680_i2c",
  76                 .acpi_match_table       = ACPI_PTR(bme680_acpi_match),
  77         },
  78         .probe = bme680_i2c_probe,
  79         .id_table = bme680_i2c_id,
  80 };
  81 module_i2c_driver(bme680_i2c_driver);
  82
  83 MODULE_AUTHOR("Himanshu Jha <himanshujha199640@gmail.com>");
  84 MODULE_DESCRIPTION("BME680 I2C driver");
  85 MODULE_LICENSE("GPL v2");