LXR linux/drivers/iio/common/st_sensors/st_sensors

   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#include <linux/of_device.h>
  16#include <linux/acpi.h>
  17
  18#include <linux/iio/common/st_sensors_i2c.h>
  19
  20
  21#define ST_SENSORS_I2C_MULTIREAD        0x80
  22
  23static unsigned int st_sensors_i2c_get_irq(struct iio_dev *indio_dev)
  24{
  25        struct st_sensor_data *sdata = iio_priv(indio_dev);
  26
  27        return to_i2c_client(sdata->dev)->irq;
  28}
  29
  30static int st_sensors_i2c_read_byte(struct st_sensor_transfer_buffer *tb,
  31                                struct device *dev, u8 reg_addr, u8 *res_byte)
  32{
  33        int err;
  34
  35        err = i2c_smbus_read_byte_data(to_i2c_client(dev), reg_addr);
  36        if (err < 0)
  37                goto st_accel_i2c_read_byte_error;
  38
  39        *res_byte = err & 0xff;
  40
  41st_accel_i2c_read_byte_error:
  42        return err < 0 ? err : 0;
  43}
  44
  45static int st_sensors_i2c_read_multiple_byte(
  46                struct st_sensor_transfer_buffer *tb, struct device *dev,
  47                        u8 reg_addr, int len, u8 *data, bool multiread_bit)
  48{
  49        if (multiread_bit)
  50                reg_addr |= ST_SENSORS_I2C_MULTIREAD;
  51
  52        return i2c_smbus_read_i2c_block_data_or_emulated(to_i2c_client(dev),
  53                                                         reg_addr, len, data);
  54}
  55
  56static int st_sensors_i2c_write_byte(struct st_sensor_transfer_buffer *tb,
  57                                struct device *dev, u8 reg_addr, u8 data)
  58{
  59        return i2c_smbus_write_byte_data(to_i2c_client(dev), reg_addr, data);
  60}
  61
  62static const struct st_sensor_transfer_function st_sensors_tf_i2c = {
  63        .read_byte = st_sensors_i2c_read_byte,
  64        .write_byte = st_sensors_i2c_write_byte,
  65        .read_multiple_byte = st_sensors_i2c_read_multiple_byte,
  66};
  67
  68void st_sensors_i2c_configure(struct iio_dev *indio_dev,
  69                struct i2c_client *client, struct st_sensor_data *sdata)
  70{
  71        i2c_set_clientdata(client, indio_dev);
  72
  73        indio_dev->dev.parent = &client->dev;
  74        indio_dev->name = client->name;
  75
  76        sdata->dev = &client->dev;
  77        sdata->tf = &st_sensors_tf_i2c;
  78        sdata->get_irq_data_ready = st_sensors_i2c_get_irq;
  79}
  80EXPORT_SYMBOL(st_sensors_i2c_configure);
  81
  82#ifdef CONFIG_ACPI
  83int st_sensors_match_acpi_device(struct device *dev)
  84{
  85        const struct acpi_device_id *acpi_id;
  86        kernel_ulong_t driver_data = 0;
  87
  88        if (ACPI_HANDLE(dev)) {
  89                acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
  90                if (!acpi_id) {
  91                        dev_err(dev, "No driver data\n");
  92                        return -EINVAL;
  93                }
  94                driver_data = acpi_id->driver_data;
  95        }
  96        return driver_data;
  97}
  98EXPORT_SYMBOL(st_sensors_match_acpi_device);
  99#endif
 100
 101MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
 102MODULE_DESCRIPTION("STMicroelectronics ST-sensors i2c driver");
 103MODULE_LICENSE("GPL v2");
 104