linux/drivers/slimbus/messaging.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Copyright (c) 2011-2017, The Linux Foundation
 */

#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include "slimbus.h"

/**
 * slim_msg_response() - Deliver Message response received from a device to the
 *			framework.
 *
 * @ctrl: Controller handle
 * @reply: Reply received from the device
 * @len: Length of the reply
 * @tid: Transaction ID received with which framework can associate reply.
 *
 * Called by controller to inform framework about the response received.
 * This helps in making the API asynchronous, and controller-driver doesn't need
 * to manage 1 more table other than the one managed by framework mapping TID
 * with buffers
 */
void slim_msg_response(struct slim_controller *ctrl, u8 *reply, u8 tid, u8 len)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * slim_alloc_txn_tid() - Allocate a tid to txn
 *
 * @ctrl: Controller handle
 * @txn: transaction to be allocated with tid.
 *
 * Return: zero on success with valid txn->tid and error code on failures.
 */
int slim_alloc_txn_tid(struct slim_controller *ctrl, struct slim_msg_txn *txn)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * slim_free_txn_tid() - Free tid of txn
 *
 * @ctrl: Controller handle
 * @txn: transaction whose tid should be freed
 */
void slim_free_txn_tid(struct slim_controller *ctrl, struct slim_msg_txn *txn)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * slim_do_transfer() - Process a SLIMbus-messaging transaction
 *
 * @ctrl: Controller handle
 * @txn: Transaction to be sent over SLIMbus
 *
 * Called by controller to transmit messaging transactions not dealing with
 * Interface/Value elements. (e.g. transmitting a message to assign logical
 * address to a slave device
 *
 * Return: -ETIMEDOUT: If transmission of this message timed out
 *	(e.g. due to bus lines not being clocked or driven by controller)
 */
int slim_do_transfer(struct slim_controller *ctrl, struct slim_msg_txn *txn)
{ … }
EXPORT_SYMBOL_GPL(…);

static int slim_val_inf_sanity(struct slim_controller *ctrl,
			       struct slim_val_inf *msg, u8 mc)
{ … }

static u16 slim_slicesize(int code)
{ … }

/**
 * slim_xfer_msg() - Transfer a value info message on slim device
 *
 * @sbdev: slim device to which this msg has to be transfered
 * @msg: value info message pointer
 * @mc: message code of the message
 *
 * Called by drivers which want to transfer a vlaue or info elements.
 *
 * Return: -ETIMEDOUT: If transmission of this message timed out
 */
int slim_xfer_msg(struct slim_device *sbdev, struct slim_val_inf *msg,
		  u8 mc)
{ … }
EXPORT_SYMBOL_GPL(…);

static void slim_fill_msg(struct slim_val_inf *msg, u32 addr,
			 size_t count, u8 *rbuf, u8 *wbuf)
{ … }

/**
 * slim_read() - Read SLIMbus value element
 *
 * @sdev: client handle.
 * @addr:  address of value element to read.
 * @count: number of bytes to read. Maximum bytes allowed are 16.
 * @val: will return what the value element value was
 *
 * Return: -EINVAL for Invalid parameters, -ETIMEDOUT If transmission of
 * this message timed out (e.g. due to bus lines not being clocked
 * or driven by controller)
 */
int slim_read(struct slim_device *sdev, u32 addr, size_t count, u8 *val)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * slim_readb() - Read byte from SLIMbus value element
 *
 * @sdev: client handle.
 * @addr:  address in the value element to read.
 *
 * Return: byte value of value element.
 */
int slim_readb(struct slim_device *sdev, u32 addr)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * slim_write() - Write SLIMbus value element
 *
 * @sdev: client handle.
 * @addr:  address in the value element to write.
 * @count: number of bytes to write. Maximum bytes allowed are 16.
 * @val: value to write to value element
 *
 * Return: -EINVAL for Invalid parameters, -ETIMEDOUT If transmission of
 * this message timed out (e.g. due to bus lines not being clocked
 * or driven by controller)
 */
int slim_write(struct slim_device *sdev, u32 addr, size_t count, u8 *val)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * slim_writeb() - Write byte to SLIMbus value element
 *
 * @sdev: client handle.
 * @addr:  address of value element to write.
 * @value: value to write to value element
 *
 * Return: -EINVAL for Invalid parameters, -ETIMEDOUT If transmission of
 * this message timed out (e.g. due to bus lines not being clocked
 * or driven by controller)
 *
 */
int slim_writeb(struct slim_device *sdev, u32 addr, u8 value)
{ … }
EXPORT_SYMBOL_GPL(…);