linux_old1/include/linux/iio/consumer.h

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/*
* Industrial I/O in kernel consumer interface
*
* Copyright (c) 2011 Jonathan Cameron
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#ifndef _IIO_INKERN_CONSUMER_H_
#define _IIO_INKERN_CONSUMER_H
#include <linux/iio/types.h>
struct iio_dev;
struct iio_chan_spec;
/**
* struct iio_channel - everything needed for a consumer to use a channel
* @indio_dev: Device on which the channel exists.
* @channel: Full description of the channel.
*/
struct iio_channel {
struct iio_dev *indio_dev;
const struct iio_chan_spec *channel;
};
/**
* iio_channel_get() - get description of all that is needed to access channel.
* @name: Unique name of the device as provided in the iio_map
* with which the desired provider to consumer mapping
* was registered.
* @consumer_channel: Unique name to identify the channel on the consumer
* side. This typically describes the channels use within
* the consumer. E.g. 'battery_voltage'
*/
struct iio_channel *iio_st_channel_get(const char *name,
const char *consumer_channel);
/**
* iio_st_channel_release() - release channels obtained via iio_st_channel_get
* @chan: The channel to be released.
*/
void iio_st_channel_release(struct iio_channel *chan);
/**
* iio_st_channel_get_all() - get all channels associated with a client
* @name: name of consumer device.
*
* Returns an array of iio_channel structures terminated with one with
* null iio_dev pointer.
* This function is used by fairly generic consumers to get all the
* channels registered as having this consumer.
*/
struct iio_channel *iio_st_channel_get_all(const char *name);
/**
* iio_st_channel_release_all() - reverse iio_st_get_all
* @chan: Array of channels to be released.
*/
void iio_st_channel_release_all(struct iio_channel *chan);
/**
* iio_st_read_channel_raw() - read from a given channel
* @channel: The channel being queried.
* @val: Value read back.
*
* Note raw reads from iio channels are in adc counts and hence
* scale will need to be applied if standard units required.
*/
int iio_st_read_channel_raw(struct iio_channel *chan,
int *val);
/**
* iio_st_get_channel_type() - get the type of a channel
* @channel: The channel being queried.
* @type: The type of the channel.
*
* returns the enum iio_chan_type of the channel
*/
int iio_st_get_channel_type(struct iio_channel *channel,
enum iio_chan_type *type);
/**
* iio_st_read_channel_scale() - read the scale value for a channel
* @channel: The channel being queried.
* @val: First part of value read back.
* @val2: Second part of value read back.
*
* Note returns a description of what is in val and val2, such
* as IIO_VAL_INT_PLUS_MICRO telling us we have a value of val
* + val2/1e6
*/
int iio_st_read_channel_scale(struct iio_channel *chan, int *val,
int *val2);
#endif