drivers/iio/common/st_sensors/st_sensors_i2c.c

   1 /*
   2  * STMicroelectronics sensors i2c library driver
   3  *
   4  * Copyright 2012-2013 STMicroelectronics Inc.
   5  *
   6  * Denis Ciocca <denis.ciocca@st.com>
   7  *
   8  * Licensed under the GPL-2.
   9  */
  10
  11 #include <linux/kernel.h>
  12 #include <linux/module.h>
  13 #include <linux/slab.h>
  14 #include <linux/iio/iio.h>
  15
  16 #include <linux/iio/common/st_sensors_i2c.h>
  17
  18
  19 #define ST_SENSORS_I2C_MULTIREAD        0x80
  20
  21 static unsigned int st_sensors_i2c_get_irq(struct iio_dev *indio_dev)
  22 {
  23         struct st_sensor_data *sdata = iio_priv(indio_dev);
  24
  25         return to_i2c_client(sdata->dev)->irq;
  26 }
  27
  28 static int st_sensors_i2c_read_byte(struct st_sensor_transfer_buffer *tb,
  29                                 struct device *dev, u8 reg_addr, u8 *res_byte)
  30 {
  31         int err;
  32
  33         err = i2c_smbus_read_byte_data(to_i2c_client(dev), reg_addr);
  34         if (err < 0)
  35                 goto st_accel_i2c_read_byte_error;
  36
  37         *res_byte = err & 0xff;
  38
  39 st_accel_i2c_read_byte_error:
  40         return err < 0 ? err : 0;
  41 }
  42
  43 static int st_sensors_i2c_read_multiple_byte(
  44                 struct st_sensor_transfer_buffer *tb, struct device *dev,
  45                         u8 reg_addr, int len, u8 *data, bool multiread_bit)
  46 {
  47         if (multiread_bit)
  48                 reg_addr |= ST_SENSORS_I2C_MULTIREAD;
  49
  50         return i2c_smbus_read_i2c_block_data(to_i2c_client(dev),
  51                                                         reg_addr, len, data);
  52 }
  53
  54 static int st_sensors_i2c_write_byte(struct st_sensor_transfer_buffer *tb,
  55                                 struct device *dev, u8 reg_addr, u8 data)
  56 {
  57         return i2c_smbus_write_byte_data(to_i2c_client(dev), reg_addr, data);
  58 }
  59
  60 static const struct st_sensor_transfer_function st_sensors_tf_i2c = {
  61         .read_byte = st_sensors_i2c_read_byte,
  62         .write_byte = st_sensors_i2c_write_byte,
  63         .read_multiple_byte = st_sensors_i2c_read_multiple_byte,
  64 };
  65
  66 void st_sensors_i2c_configure(struct iio_dev *indio_dev,
  67                 struct i2c_client *client, struct st_sensor_data *sdata)
  68 {
  69         i2c_set_clientdata(client, indio_dev);
  70
  71         indio_dev->dev.parent = &client->dev;
  72         indio_dev->name = client->name;
  73
  74         sdata->tf = &st_sensors_tf_i2c;
  75         sdata->get_irq_data_ready = st_sensors_i2c_get_irq;
  76 }
  77 EXPORT_SYMBOL(st_sensors_i2c_configure);
  78
  79 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
  80 MODULE_DESCRIPTION("STMicroelectronics ST-sensors i2c driver");
  81 MODULE_LICENSE("GPL v2");