include/linux/iio/backend.h

/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _IIO_BACKEND_H_
#define _IIO_BACKEND_H_

#include <linux/types.h>

struct iio_chan_spec;
struct fwnode_handle;
struct iio_backend;
struct device;
struct iio_dev;

enum iio_backend_data_type {
	IIO_BACKEND_TWOS_COMPLEMENT,
	IIO_BACKEND_OFFSET_BINARY,
	IIO_BACKEND_DATA_TYPE_MAX
};

enum iio_backend_data_source {
	IIO_BACKEND_INTERNAL_CONTINUOS_WAVE,
	IIO_BACKEND_EXTERNAL,
	IIO_BACKEND_DATA_SOURCE_MAX
};

/**
 * IIO_BACKEND_EX_INFO - Helper for an IIO extended channel attribute
 * @_name:	Attribute name
 * @_shared:	Whether the attribute is shared between all channels
 * @_what:	Data private to the driver
 */
#define IIO_BACKEND_EX_INFO(_name, _shared, _what) {	\
	.name = (_name),				\
	.shared = (_shared),				\
	.read =  iio_backend_ext_info_get,		\
	.write = iio_backend_ext_info_set,		\
	.private = (_what),				\
}

/**
 * struct iio_backend_data_fmt - Backend data format
 * @type:		Data type.
 * @sign_extend:	Bool to tell if the data is sign extended.
 * @enable:		Enable/Disable the data format module. If disabled,
 *			not formatting will happen.
 */
struct iio_backend_data_fmt {
	enum iio_backend_data_type type;
	bool sign_extend;
	bool enable;
};

/**
 * struct iio_backend_ops - operations structure for an iio_backend
 * @enable:		Enable backend.
 * @disable:		Disable backend.
 * @chan_enable:	Enable one channel.
 * @chan_disable:	Disable one channel.
 * @data_format_set:	Configure the data format for a specific channel.
 * @data_source_set:	Configure the data source for a specific channel.
 * @set_sample_rate:	Configure the sampling rate for a specific channel.
 * @request_buffer:	Request an IIO buffer.
 * @free_buffer:	Free an IIO buffer.
 * @extend_chan_spec:	Extend an IIO channel.
 * @ext_info_set:	Extended info setter.
 * @ext_info_get:	Extended info getter.
 **/
struct iio_backend_ops {
	int (*enable)(struct iio_backend *back);
	void (*disable)(struct iio_backend *back);
	int (*chan_enable)(struct iio_backend *back, unsigned int chan);
	int (*chan_disable)(struct iio_backend *back, unsigned int chan);
	int (*data_format_set)(struct iio_backend *back, unsigned int chan,
			       const struct iio_backend_data_fmt *data);
	int (*data_source_set)(struct iio_backend *back, unsigned int chan,
			       enum iio_backend_data_source data);
	int (*set_sample_rate)(struct iio_backend *back, unsigned int chan,
			       u64 sample_rate_hz);
	struct iio_buffer *(*request_buffer)(struct iio_backend *back,
					     struct iio_dev *indio_dev);
	void (*free_buffer)(struct iio_backend *back,
			    struct iio_buffer *buffer);
	int (*extend_chan_spec)(struct iio_backend *back,
				struct iio_chan_spec *chan);
	int (*ext_info_set)(struct iio_backend *back, uintptr_t private,
			    const struct iio_chan_spec *chan,
			    const char *buf, size_t len);
	int (*ext_info_get)(struct iio_backend *back, uintptr_t private,
			    const struct iio_chan_spec *chan, char *buf);
};

int iio_backend_chan_enable(struct iio_backend *back, unsigned int chan);
int iio_backend_chan_disable(struct iio_backend *back, unsigned int chan);
int devm_iio_backend_enable(struct device *dev, struct iio_backend *back);
int iio_backend_data_format_set(struct iio_backend *back, unsigned int chan,
				const struct iio_backend_data_fmt *data);
int iio_backend_data_source_set(struct iio_backend *back, unsigned int chan,
				enum iio_backend_data_source data);
int iio_backend_set_sampling_freq(struct iio_backend *back, unsigned int chan,
				  u64 sample_rate_hz);
int devm_iio_backend_request_buffer(struct device *dev,
				    struct iio_backend *back,
				    struct iio_dev *indio_dev);
ssize_t iio_backend_ext_info_set(struct iio_dev *indio_dev, uintptr_t private,
				 const struct iio_chan_spec *chan,
				 const char *buf, size_t len);
ssize_t iio_backend_ext_info_get(struct iio_dev *indio_dev, uintptr_t private,
				 const struct iio_chan_spec *chan, char *buf);

int iio_backend_extend_chan_spec(struct iio_dev *indio_dev,
				 struct iio_backend *back,
				 struct iio_chan_spec *chan);
void *iio_backend_get_priv(const struct iio_backend *conv);
struct iio_backend *devm_iio_backend_get(struct device *dev, const char *name);
struct iio_backend *
__devm_iio_backend_get_from_fwnode_lookup(struct device *dev,
					  struct fwnode_handle *fwnode);

int devm_iio_backend_register(struct device *dev,
			      const struct iio_backend_ops *ops, void *priv);

#endif