LXR linux/drivers/iio/magnetometer/st_magn

   1/*
   2 * STMicroelectronics magnetometers 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/module.h>
  12#include <linux/kernel.h>
  13#include <linux/slab.h>
  14#include <linux/stat.h>
  15#include <linux/interrupt.h>
  16#include <linux/i2c.h>
  17#include <linux/delay.h>
  18#include <linux/iio/iio.h>
  19#include <linux/iio/buffer.h>
  20#include <linux/iio/trigger_consumer.h>
  21#include <linux/iio/triggered_buffer.h>
  22
  23#include <linux/iio/common/st_sensors.h>
  24#include "st_magn.h"
  25
  26static int st_magn_buffer_preenable(struct iio_dev *indio_dev)
  27{
  28        return st_sensors_set_enable(indio_dev, true);
  29}
  30
  31static int st_magn_buffer_postenable(struct iio_dev *indio_dev)
  32{
  33        int err;
  34        struct st_sensor_data *mdata = iio_priv(indio_dev);
  35
  36        mdata->buffer_data = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);
  37        if (mdata->buffer_data == NULL) {
  38                err = -ENOMEM;
  39                goto allocate_memory_error;
  40        }
  41
  42        err = iio_triggered_buffer_postenable(indio_dev);
  43        if (err < 0)
  44                goto st_magn_buffer_postenable_error;
  45
  46        return err;
  47
  48st_magn_buffer_postenable_error:
  49        kfree(mdata->buffer_data);
  50allocate_memory_error:
  51        return err;
  52}
  53
  54static int st_magn_buffer_predisable(struct iio_dev *indio_dev)
  55{
  56        int err;
  57        struct st_sensor_data *mdata = iio_priv(indio_dev);
  58
  59        err = iio_triggered_buffer_predisable(indio_dev);
  60        if (err < 0)
  61                goto st_magn_buffer_predisable_error;
  62
  63        err = st_sensors_set_enable(indio_dev, false);
  64
  65st_magn_buffer_predisable_error:
  66        kfree(mdata->buffer_data);
  67        return err;
  68}
  69
  70static const struct iio_buffer_setup_ops st_magn_buffer_setup_ops = {
  71        .preenable = &st_magn_buffer_preenable,
  72        .postenable = &st_magn_buffer_postenable,
  73        .predisable = &st_magn_buffer_predisable,
  74};
  75
  76int st_magn_allocate_ring(struct iio_dev *indio_dev)
  77{
  78        return iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time,
  79                &st_sensors_trigger_handler, &st_magn_buffer_setup_ops);
  80}
  81
  82void st_magn_deallocate_ring(struct iio_dev *indio_dev)
  83{
  84        iio_triggered_buffer_cleanup(indio_dev);
  85}
  86
  87MODULE_AUTHOR("Denis Ciocca <denis.ciocca@st.com>");
  88MODULE_DESCRIPTION("STMicroelectronics magnetometers buffer");
  89MODULE_LICENSE("GPL v2");
  90