drivers/iio/common/st_sensors/st_sensors_i2c.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * STMicroelectronics sensors i2c library driver
   4  *
   5  * Copyright 2012-2013 STMicroelectronics Inc.
   6  *
   7  * Denis Ciocca <denis.ciocca@st.com>
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/module.h>
  12 #include <linux/slab.h>
  13 #include <linux/iio/iio.h>
  14 #include <linux/of_device.h>
  15 #include <linux/acpi.h>
  16
  17 #include <linux/iio/common/st_sensors_i2c.h>
  18
  19
  20 #define ST_SENSORS_I2C_MULTIREAD        0x80
  21
  22 static unsigned int st_sensors_i2c_get_irq(struct iio_dev *indio_dev)
  23 {
  24         struct st_sensor_data *sdata = iio_priv(indio_dev);
  25
  26         return to_i2c_client(sdata->dev)->irq;
  27 }
  28
  29 static int st_sensors_i2c_read_byte(struct st_sensor_transfer_buffer *tb,
  30                                 struct device *dev, u8 reg_addr, u8 *res_byte)
  31 {
  32         int err;
  33
  34         err = i2c_smbus_read_byte_data(to_i2c_client(dev), reg_addr);
  35         if (err < 0)
  36                 goto st_accel_i2c_read_byte_error;
  37
  38         *res_byte = err & 0xff;
  39
  40 st_accel_i2c_read_byte_error:
  41         return err < 0 ? err : 0;
  42 }
  43
  44 static int st_sensors_i2c_read_multiple_byte(
  45                 struct st_sensor_transfer_buffer *tb, struct device *dev,
  46                         u8 reg_addr, int len, u8 *data, bool multiread_bit)
  47 {
  48         if (multiread_bit)
  49                 reg_addr |= ST_SENSORS_I2C_MULTIREAD;
  50
  51         return i2c_smbus_read_i2c_block_data_or_emulated(to_i2c_client(dev),
  52                                                          reg_addr, len, data);
  53 }
  54
  55 static int st_sensors_i2c_write_byte(struct st_sensor_transfer_buffer *tb,
  56                                 struct device *dev, u8 reg_addr, u8 data)
  57 {
  58         return i2c_smbus_write_byte_data(to_i2c_client(dev), reg_addr, data);
  59 }
  60
  61 static const struct st_sensor_transfer_function st_sensors_tf_i2c = {
  62         .read_byte = st_sensors_i2c_read_byte,
  63         .write_byte = st_sensors_i2c_write_byte,
  64         .read_multiple_byte = st_sensors_i2c_read_multiple_byte,
  65 };
  66
  67 void st_sensors_i2c_configure(struct iio_dev *indio_dev,
  68                 struct i2c_client *client, struct st_sensor_data *sdata)
  69 {
  70         i2c_set_clientdata(client, indio_dev);
  71
  72         indio_dev->dev.parent = &client->dev;
  73         indio_dev->name = client->name;
  74
  75         sdata->dev = &client->dev;
  76         sdata->tf = &st_sensors_tf_i2c;
  77         sdata->get_irq_data_ready = st_sensors_i2c_get_irq;
  78 }
  79 EXPORT_SYMBOL(st_sensors_i2c_configure);
  80
  81 #ifdef CONFIG_ACPI
  82 int st_sensors_match_acpi_device(struct device *dev)
  83 {
  84         const struct acpi_device_id *acpi_id;
  85         kernel_ulong_t driver_data = 0;
  86
  87         if (ACPI_HANDLE(dev)) {
  88                 acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
  89                 if (!acpi_id) {
  90                         dev_err(dev, "No driver data\n");
  91                         return -EINVAL;
  92                 }
  93                 driver_data = acpi_id->driver_data;
  94         }
  95         return driver_data;
  96 }
  97 EXPORT_SYMBOL(st_sensors_match_acpi_device);
  98 #endif
  99
 100 MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
 101 MODULE_DESCRIPTION("STMicroelectronics ST-sensors i2c driver");
 102 MODULE_LICENSE("GPL v2");