i2c_transaction_queue.h File Reference

FIFO data structure used to store handles to client I2C transaction requests. More...

#include "i2c.h"

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Macros
#define	I2C_TRANSACTION_QUEUE_SIZE   10
	Adjust to increase/decrease the queue size.

Enumerations
enum	i2c_queue_status_t {   _I2C_QUEUE_STATUS_ENUM_MIN = 0 , I2C_QUEUE_STATUS_SUCCESS = _I2C_QUEUE_STATUS_ENUM_MIN , I2C_QUEUE_STATUS_FAIL , I2C_QUEUE_STATUS_QUEUE_FULL ,   I2C_QUEUE_STATUS_QUEUE_EMPTY , _I2C_QUEUE_STATUS_ENUM_MAX }
	Possible return types for queue operations. More...

Functions
i2c_queue_status_t	i2c_transaction_queue_add (hal_i2c_txn_t *txn)
	Add a transaction to the queue. More...
i2c_queue_status_t	i2c_transaction_queue_get_next (hal_i2c_txn_t **txn)
	Get the next transaction from the queue. Removes the transaction from the queue. More...
void	i2c_transaction_queue_reset ()
	Resets the queue. More...

Detailed Description

FIFO data structure used to store handles to client I2C transaction requests.

Note

Clients are responsible for owning the memory for their transactions. This queue only holds handles to the transactions so they may be processed in order.

Warning

Undefined behavior will occur if the transaction added to queue was located on a function's call stack that then returns.

Copyright (c) 2025 Cory McKiel. Licensed under the MIT License. See LICENSE file in the project root.

Enumeration Type Documentation

i2c_queue_status_t

enum i2c_queue_status_t

Possible return types for queue operations.

Enumerator
_I2C_QUEUE_STATUS_ENUM_MIN	Lower bound of enum. Inclusive.
I2C_QUEUE_STATUS_SUCCESS	The queue operation was successful.
I2C_QUEUE_STATUS_FAIL	The queue operation encountered an error and was not successful.
I2C_QUEUE_STATUS_QUEUE_FULL	The queue operation could not be performed because the queue is full.
I2C_QUEUE_STATUS_QUEUE_EMPTY	The queue operation could not be performed because the queue is empty.
_I2C_QUEUE_STATUS_ENUM_MAX	Upper bound of enum. Exclusive.

Function Documentation

i2c_transaction_queue_add()

i2c_queue_status_t i2c_transaction_queue_add

(

hal_i2c_txn_t *

txn

)

Add a transaction to the queue.

Parameters

txn	A reference to the transaction to queue.

Warning

Clients are responsible for maintaining the memory for their transactions. This merely queues a handle.

Returns

The status of the request. SUCCESS is the only return value indicating the request was queued.

i2c_transaction_queue_get_next()

i2c_queue_status_t i2c_transaction_queue_get_next

(

hal_i2c_txn_t **

txn

)

Get the next transaction from the queue. Removes the transaction from the queue.

Parameters

txn	A reference to a handle type for a transaction.

Note

txn is a double pointer because the client is meant to pass in a null handle that they want set to point to the next transaction to process. But to actually set a param, there needs to be a reference to it, hence, the double pointer.

Returns

The status of the request. SUCCESS is the only return value indicating the next transaction was properly dequeued.

i2c_transaction_queue_reset()

void i2c_transaction_queue_reset

(

)

Resets the queue.

It resets all internal variables that manage the queue so it will be "like new".