drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i2c.c

   1 /*
   2  * STMicroelectronics st_lsm6dsx i2c driver
   3  *
   4  * Copyright 2016 STMicroelectronics Inc.
   5  *
   6  * Lorenzo Bianconi <lorenzo.bianconi@st.com>
   7  * Denis Ciocca <denis.ciocca@st.com>
   8  *
   9  * Licensed under the GPL-2.
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/i2c.h>
  15 #include <linux/slab.h>
  16 #include <linux/of.h>
  17
  18 #include "st_lsm6dsx.h"
  19
  20 static int st_lsm6dsx_i2c_read(struct device *dev, u8 addr, int len, u8 *data)
  21 {
  22         struct i2c_client *client = to_i2c_client(dev);
  23         struct i2c_msg msg[2];
  24
  25         msg[0].addr = client->addr;
  26         msg[0].flags = client->flags;
  27         msg[0].len = 1;
  28         msg[0].buf = &addr;
  29
  30         msg[1].addr = client->addr;
  31         msg[1].flags = client->flags | I2C_M_RD;
  32         msg[1].len = len;
  33         msg[1].buf = data;
  34
  35         return i2c_transfer(client->adapter, msg, 2);
  36 }
  37
  38 static int st_lsm6dsx_i2c_write(struct device *dev, u8 addr, int len, u8 *data)
  39 {
  40         struct i2c_client *client = to_i2c_client(dev);
  41         struct i2c_msg msg;
  42         u8 send[len + 1];
  43
  44         send[0] = addr;
  45         memcpy(&send[1], data, len * sizeof(u8));
  46
  47         msg.addr = client->addr;
  48         msg.flags = client->flags;
  49         msg.len = len + 1;
  50         msg.buf = send;
  51
  52         return i2c_transfer(client->adapter, &msg, 1);
  53 }
  54
  55 static const struct st_lsm6dsx_transfer_function st_lsm6dsx_transfer_fn = {
  56         .read = st_lsm6dsx_i2c_read,
  57         .write = st_lsm6dsx_i2c_write,
  58 };
  59
  60 static int st_lsm6dsx_i2c_probe(struct i2c_client *client,
  61                                 const struct i2c_device_id *id)
  62 {
  63         return st_lsm6dsx_probe(&client->dev, client->irq,
  64                                 (int)id->driver_data, id->name,
  65                                 &st_lsm6dsx_transfer_fn);
  66 }
  67
  68 static const struct of_device_id st_lsm6dsx_i2c_of_match[] = {
  69         {
  70                 .compatible = "st,lsm6ds3",
  71                 .data = (void *)ST_LSM6DS3_ID,
  72         },
  73         {
  74                 .compatible = "st,lsm6ds3h",
  75                 .data = (void *)ST_LSM6DS3H_ID,
  76         },
  77         {
  78                 .compatible = "st,lsm6dsl",
  79                 .data = (void *)ST_LSM6DSL_ID,
  80         },
  81         {
  82                 .compatible = "st,lsm6dsm",
  83                 .data = (void *)ST_LSM6DSM_ID,
  84         },
  85         {},
  86 };
  87 MODULE_DEVICE_TABLE(of, st_lsm6dsx_i2c_of_match);
  88
  89 static const struct i2c_device_id st_lsm6dsx_i2c_id_table[] = {
  90         { ST_LSM6DS3_DEV_NAME, ST_LSM6DS3_ID },
  91         { ST_LSM6DS3H_DEV_NAME, ST_LSM6DS3H_ID },
  92         { ST_LSM6DSL_DEV_NAME, ST_LSM6DSL_ID },
  93         { ST_LSM6DSM_DEV_NAME, ST_LSM6DSM_ID },
  94         {},
  95 };
  96 MODULE_DEVICE_TABLE(i2c, st_lsm6dsx_i2c_id_table);
  97
  98 static struct i2c_driver st_lsm6dsx_driver = {
  99         .driver = {
 100                 .name = "st_lsm6dsx_i2c",
 101                 .pm = &st_lsm6dsx_pm_ops,
 102                 .of_match_table = of_match_ptr(st_lsm6dsx_i2c_of_match),
 103         },
 104         .probe = st_lsm6dsx_i2c_probe,
 105         .id_table = st_lsm6dsx_i2c_id_table,
 106 };
 107 module_i2c_driver(st_lsm6dsx_driver);
 108
 109 MODULE_AUTHOR("Lorenzo Bianconi <lorenzo.bianconi@st.com>");
 110 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
 111 MODULE_DESCRIPTION("STMicroelectronics st_lsm6dsx i2c driver");
 112 MODULE_LICENSE("GPL v2");