Something went wrong. Try again.
Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Something went wrong. Try again.
123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303304305306307308309310311312313314315316317318319320321322323324325326327328329330331332333334335336337338339340341342343344345346347348349350351352353354355356357358359360361362363364365366367368369370371372373374375376377378379380381382383384385386387388389390391392393394395396397398399400401402403404405406407408409410411412413414415416417418419420421422423424425426427428429430431432433434435436437438439440441442443444445446447448449450451452453454455456457458459460461462463464465466467468469470471472473474/* SPDX-License-Identifier: GPL-2.0-only *//* * Industrial I/O in kernel consumer interface * * Copyright (c) 2011 Jonathan Cameron */#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 fwnode_handle;
/** * 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);/** * 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);
/** * fwnode_iio_channel_get_by_name() - get description of all that is needed to access channel. * @fwnode: Pointer to consumer Firmware node * @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 *fwnode_iio_channel_get_by_name(struct fwnode_handle *fwnode, const char *name);
/** * devm_fwnode_iio_channel_get_by_name() - Resource managed version of * fwnode_iio_channel_get_by_name(). * @dev: Pointer to consumer device. * @fwnode: Pointer to consumer Firmware node * @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_fwnode_iio_channel_get_by_name(struct device *dev, struct fwnode_handle *fwnode, const char *consumer_channel);
struct iio_cb_buffer;/** * iio_channel_get_all_cb() - register callback for triggered capture * @dev: Pointer to client device. * @cb: Callback function. Must be safe to call from any context * (e.g. must not sleep). * @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, if standard units are required, raw reads from iio channels * need the offset (default 0) and scale (default 1) to be applied * as (raw + offset) * scale. */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, if standard units are required, raw reads from iio channels * need the offset (default 0) and scale (default 1) to be applied * as (raw + offset) * scale. * * 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_read_channel_processed_scale() - read and scale a processed value * @chan: The channel being queried. * @val: Value read back. * @scale: Scale factor to apply during the conversion * * Returns an error code or 0. * * This function will read a processed value from a channel. This will work * like @iio_read_channel_processed() but also scale with an additional * scale factor while attempting to minimize any precision loss. */int iio_read_channel_processed_scale(struct iio_channel *chan, int *val, unsigned int scale);
/** * 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 that for raw writes to iio channels, if the value provided is * in standard units, the affect of the scale and offset must be removed * as (value / scale) - offset. */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, if standard units are required, raw reads from iio channels * need the offset (default 0) and scale (default 1) to be applied * as (raw + offset) * scale. */int iio_read_max_channel_raw(struct iio_channel *chan, int *val);
/** * iio_read_min_channel_raw() - read minimum available raw value from a given * channel, i.e. the minimum possible value. * @chan: The channel being queried. * @val: Value read back. * * Note, if standard units are required, raw reads from iio channels * need the offset (default 0) and scale (default 1) to be applied * as (raw + offset) * scale. */int iio_read_min_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, if standard units are required, raw available values from iio * channels need the offset (default 0) and scale (default 1) to be applied * as (raw + offset) * scale. */int iio_read_avail_channel_raw(struct iio_channel *chan, const int **vals, int *length);
/** * iio_read_avail_channel_attribute() - read available channel attribute values * @chan: The channel being queried. * @vals: Available values read back. * @type: Type of values read back. * @length: Number of entries in vals. * @attribute: info attribute to be read back. * * Returns an error code, IIO_AVAIL_RANGE or IIO_AVAIL_LIST. */int iio_read_avail_channel_attribute(struct iio_channel *chan, const int **vals, int *type, int *length, enum iio_chan_info_enum attribute);
/** * 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_multiply_value() - Multiply an IIO value * @result: Destination pointer for the multiplication result * @multiplier: Multiplier. * @type: One of the IIO_VAL_* constants. This decides how the @val and * @val2 parameters are interpreted. * @val: Value being multiplied. * @val2: Value being multiplied. @val2 use depends on type. * * Multiply an IIO value with a s64 multiplier storing the result as * IIO_VAL_INT. This is typically used for scaling. * * Returns: * IIO_VAL_INT on success or a negative error-number on failure. */int iio_multiply_value(int *result, s64 multiplier, unsigned int type, 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 and to be aligned at PAGE_SIZE. * * 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);
/** * iio_read_channel_label() - read label for a given channel * @chan: The channel being queried. * @buf: Where to store the attribute value. Assumed to hold * at least PAGE_SIZE bytes and to be aligned at PAGE_SIZE. * * Returns the number of bytes written to buf, or an error code. */ssize_t iio_read_channel_label(struct iio_channel *chan, char *buf);
#endif