390 lines
13 KiB
C
390 lines
13 KiB
C
/*
|
|
* 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/types.h>
|
|
#include <linux/iio/types.h>
|
|
|
|
struct iio_dev;
|
|
struct iio_chan_spec;
|
|
struct device;
|
|
|
|
/**
|
|
* 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.
|
|
* @data: Data about the channel used by consumer.
|
|
*/
|
|
struct iio_channel {
|
|
struct iio_dev *indio_dev;
|
|
const struct iio_chan_spec *channel;
|
|
void *data;
|
|
};
|
|
|
|
/**
|
|
* iio_channel_get() - get description of all that is needed to access channel.
|
|
* @dev: Pointer to consumer device. Device name must match
|
|
* the 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_channel_get(struct device *dev,
|
|
const char *consumer_channel);
|
|
|
|
/**
|
|
* iio_channel_release() - release channels obtained via iio_channel_get
|
|
* @chan: The channel to be released.
|
|
*/
|
|
void iio_channel_release(struct iio_channel *chan);
|
|
|
|
/**
|
|
* devm_iio_channel_get() - Resource managed version of iio_channel_get().
|
|
* @dev: Pointer to consumer device. Device name must match
|
|
* the 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'
|
|
*
|
|
* Returns a pointer to negative errno if it is not able to get the iio channel
|
|
* otherwise returns valid pointer for iio channel.
|
|
*
|
|
* The allocated iio channel is automatically released when the device is
|
|
* unbound.
|
|
*/
|
|
struct iio_channel *devm_iio_channel_get(struct device *dev,
|
|
const char *consumer_channel);
|
|
/**
|
|
* devm_iio_channel_release() - Resource managed version of
|
|
* iio_channel_release().
|
|
* @dev: Pointer to consumer device for which resource
|
|
* is allocared.
|
|
* @chan: The channel to be released.
|
|
*/
|
|
void devm_iio_channel_release(struct device *dev, struct iio_channel *chan);
|
|
|
|
/**
|
|
* iio_channel_get_all() - get all channels associated with a client
|
|
* @dev: Pointer to 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_channel_get_all(struct device *dev);
|
|
|
|
/**
|
|
* iio_channel_release_all() - reverse iio_channel_get_all
|
|
* @chan: Array of channels to be released.
|
|
*/
|
|
void iio_channel_release_all(struct iio_channel *chan);
|
|
|
|
/**
|
|
* devm_iio_channel_get_all() - Resource managed version of
|
|
* iio_channel_get_all().
|
|
* @dev: Pointer to consumer device.
|
|
*
|
|
* Returns a pointer to negative errno if it is not able to get the iio channel
|
|
* otherwise 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.
|
|
*
|
|
* The allocated iio channels are automatically released when the device is
|
|
* unbounded.
|
|
*/
|
|
struct iio_channel *devm_iio_channel_get_all(struct device *dev);
|
|
|
|
/**
|
|
* devm_iio_channel_release_all() - Resource managed version of
|
|
* iio_channel_release_all().
|
|
* @dev: Pointer to consumer device for which resource
|
|
* is allocared.
|
|
* @chan: Array channel to be released.
|
|
*/
|
|
void devm_iio_channel_release_all(struct device *dev, struct iio_channel *chan);
|
|
|
|
struct iio_cb_buffer;
|
|
/**
|
|
* iio_channel_get_all_cb() - register callback for triggered capture
|
|
* @dev: Pointer to client device.
|
|
* @cb: Callback function.
|
|
* @private: Private data passed to callback.
|
|
*
|
|
* NB right now we have no ability to mux data from multiple devices.
|
|
* So if the channels requested come from different devices this will
|
|
* fail.
|
|
*/
|
|
struct iio_cb_buffer *iio_channel_get_all_cb(struct device *dev,
|
|
int (*cb)(const void *data,
|
|
void *private),
|
|
void *private);
|
|
/**
|
|
* iio_channel_cb_set_buffer_watermark() - set the buffer watermark.
|
|
* @cb_buffer: The callback buffer from whom we want the channel
|
|
* information.
|
|
* @watermark: buffer watermark in bytes.
|
|
*
|
|
* This function allows to configure the buffer watermark.
|
|
*/
|
|
int iio_channel_cb_set_buffer_watermark(struct iio_cb_buffer *cb_buffer,
|
|
size_t watermark);
|
|
|
|
/**
|
|
* iio_channel_release_all_cb() - release and unregister the callback.
|
|
* @cb_buffer: The callback buffer that was allocated.
|
|
*/
|
|
void iio_channel_release_all_cb(struct iio_cb_buffer *cb_buffer);
|
|
|
|
/**
|
|
* iio_channel_start_all_cb() - start the flow of data through callback.
|
|
* @cb_buff: The callback buffer we are starting.
|
|
*/
|
|
int iio_channel_start_all_cb(struct iio_cb_buffer *cb_buff);
|
|
|
|
/**
|
|
* iio_channel_stop_all_cb() - stop the flow of data through the callback.
|
|
* @cb_buff: The callback buffer we are stopping.
|
|
*/
|
|
void iio_channel_stop_all_cb(struct iio_cb_buffer *cb_buff);
|
|
|
|
/**
|
|
* iio_channel_cb_get_channels() - get access to the underlying channels.
|
|
* @cb_buffer: The callback buffer from whom we want the channel
|
|
* information.
|
|
*
|
|
* This function allows one to obtain information about the channels.
|
|
* Whilst this may allow direct reading if all buffers are disabled, the
|
|
* primary aim is to allow drivers that are consuming a channel to query
|
|
* things like scaling of the channel.
|
|
*/
|
|
struct iio_channel
|
|
*iio_channel_cb_get_channels(const struct iio_cb_buffer *cb_buffer);
|
|
|
|
/**
|
|
* iio_channel_cb_get_iio_dev() - get access to the underlying device.
|
|
* @cb_buffer: The callback buffer from whom we want the device
|
|
* information.
|
|
*
|
|
* This function allows one to obtain information about the device.
|
|
* The primary aim is to allow drivers that are consuming a device to query
|
|
* things like current trigger.
|
|
*/
|
|
struct iio_dev
|
|
*iio_channel_cb_get_iio_dev(const struct iio_cb_buffer *cb_buffer);
|
|
|
|
/**
|
|
* iio_read_channel_raw() - read from a given channel
|
|
* @chan: 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_read_channel_raw(struct iio_channel *chan,
|
|
int *val);
|
|
|
|
/**
|
|
* iio_read_channel_average_raw() - read from a given channel
|
|
* @chan: 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.
|
|
*
|
|
* In opposit to the normal iio_read_channel_raw this function
|
|
* returns the average of multiple reads.
|
|
*/
|
|
int iio_read_channel_average_raw(struct iio_channel *chan, int *val);
|
|
|
|
/**
|
|
* iio_read_channel_processed() - read processed value from a given channel
|
|
* @chan: The channel being queried.
|
|
* @val: Value read back.
|
|
*
|
|
* Returns an error code or 0.
|
|
*
|
|
* This function will read a processed value from a channel. A processed value
|
|
* means that this value will have the correct unit and not some device internal
|
|
* representation. If the device does not support reporting a processed value
|
|
* the function will query the raw value and the channels scale and offset and
|
|
* do the appropriate transformation.
|
|
*/
|
|
int iio_read_channel_processed(struct iio_channel *chan, int *val);
|
|
|
|
/**
|
|
* iio_write_channel_attribute() - Write values to the device attribute.
|
|
* @chan: The channel being queried.
|
|
* @val: Value being written.
|
|
* @val2: Value being written.val2 use depends on attribute type.
|
|
* @attribute: info attribute to be read.
|
|
*
|
|
* Returns an error code or 0.
|
|
*/
|
|
int iio_write_channel_attribute(struct iio_channel *chan, int val,
|
|
int val2, enum iio_chan_info_enum attribute);
|
|
|
|
/**
|
|
* iio_read_channel_attribute() - Read values from the device attribute.
|
|
* @chan: The channel being queried.
|
|
* @val: Value being written.
|
|
* @val2: Value being written.Val2 use depends on attribute type.
|
|
* @attribute: info attribute to be written.
|
|
*
|
|
* Returns an error code if failed. Else 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_read_channel_attribute(struct iio_channel *chan, int *val,
|
|
int *val2, enum iio_chan_info_enum attribute);
|
|
|
|
/**
|
|
* iio_write_channel_raw() - write to a given channel
|
|
* @chan: The channel being queried.
|
|
* @val: Value being written.
|
|
*
|
|
* Note raw writes to iio channels are in dac counts and hence
|
|
* scale will need to be applied if standard units required.
|
|
*/
|
|
int iio_write_channel_raw(struct iio_channel *chan, int val);
|
|
|
|
/**
|
|
* iio_read_max_channel_raw() - read maximum available raw value from a given
|
|
* channel, i.e. the maximum possible value.
|
|
* @chan: 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 are required.
|
|
*/
|
|
int iio_read_max_channel_raw(struct iio_channel *chan, int *val);
|
|
|
|
/**
|
|
* iio_read_avail_channel_raw() - read available raw values from a given channel
|
|
* @chan: The channel being queried.
|
|
* @vals: Available values read back.
|
|
* @length: Number of entries in vals.
|
|
*
|
|
* Returns an error code, IIO_AVAIL_RANGE or IIO_AVAIL_LIST.
|
|
*
|
|
* For ranges, three vals are always returned; min, step and max.
|
|
* For lists, all the possible values are enumerated.
|
|
*
|
|
* Note raw available values from iio channels are in adc counts and
|
|
* hence scale will need to be applied if standard units are required.
|
|
*/
|
|
int iio_read_avail_channel_raw(struct iio_channel *chan,
|
|
const int **vals, int *length);
|
|
|
|
/**
|
|
* iio_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_get_channel_type(struct iio_channel *channel,
|
|
enum iio_chan_type *type);
|
|
|
|
/**
|
|
* iio_read_channel_offset() - read the offset value for a channel
|
|
* @chan: 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_read_channel_offset(struct iio_channel *chan, int *val,
|
|
int *val2);
|
|
|
|
/**
|
|
* iio_read_channel_scale() - read the scale value for a channel
|
|
* @chan: 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_read_channel_scale(struct iio_channel *chan, int *val,
|
|
int *val2);
|
|
|
|
/**
|
|
* iio_convert_raw_to_processed() - Converts a raw value to a processed value
|
|
* @chan: The channel being queried
|
|
* @raw: The raw IIO to convert
|
|
* @processed: The result of the conversion
|
|
* @scale: Scale factor to apply during the conversion
|
|
*
|
|
* Returns an error code or 0.
|
|
*
|
|
* This function converts a raw value to processed value for a specific channel.
|
|
* A raw value is the device internal representation of a sample and the value
|
|
* returned by iio_read_channel_raw, so the unit of that value is device
|
|
* depended. A processed value on the other hand is value has a normed unit
|
|
* according with the IIO specification.
|
|
*
|
|
* The scale factor allows to increase the precession of the returned value. For
|
|
* a scale factor of 1 the function will return the result in the normal IIO
|
|
* unit for the channel type. E.g. millivolt for voltage channels, if you want
|
|
* nanovolts instead pass 1000000 as the scale factor.
|
|
*/
|
|
int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
|
|
int *processed, unsigned int scale);
|
|
|
|
/**
|
|
* iio_get_channel_ext_info_count() - get number of ext_info attributes
|
|
* connected to the channel.
|
|
* @chan: The channel being queried
|
|
*
|
|
* Returns the number of ext_info attributes
|
|
*/
|
|
unsigned int iio_get_channel_ext_info_count(struct iio_channel *chan);
|
|
|
|
/**
|
|
* iio_read_channel_ext_info() - read ext_info attribute from a given channel
|
|
* @chan: The channel being queried.
|
|
* @attr: The ext_info attribute to read.
|
|
* @buf: Where to store the attribute value. Assumed to hold
|
|
* at least PAGE_SIZE bytes.
|
|
*
|
|
* Returns the number of bytes written to buf (perhaps w/o zero termination;
|
|
* it need not even be a string), or an error code.
|
|
*/
|
|
ssize_t iio_read_channel_ext_info(struct iio_channel *chan,
|
|
const char *attr, char *buf);
|
|
|
|
/**
|
|
* iio_write_channel_ext_info() - write ext_info attribute from a given channel
|
|
* @chan: The channel being queried.
|
|
* @attr: The ext_info attribute to read.
|
|
* @buf: The new attribute value. Strings needs to be zero-
|
|
* terminated, but the terminator should not be included
|
|
* in the below len.
|
|
* @len: The size of the new attribute value.
|
|
*
|
|
* Returns the number of accepted bytes, which should be the same as len.
|
|
* An error code can also be returned.
|
|
*/
|
|
ssize_t iio_write_channel_ext_info(struct iio_channel *chan, const char *attr,
|
|
const char *buf, size_t len);
|
|
|
|
#endif
|