Transport

SCMI Transport Layer abstraction and definitions. More...

Topics
	Shared Memory
	Shared memory transport definitions for SCMI.

Files
file	transport.h
	Header file for the SCMI Transport Layer.

Data Structures
struct	scmi_channel
	SCMI channel structure. More...
struct	scmi_transport_api

Typedefs
typedef void(*	scmi_channel_cb) (struct scmi_channel *chan)
	Callback function for message replies.

Functions
static struct scmi_channel *	scmi_transport_request_channel (const struct device *transport, uint32_t proto, bool tx)
	Request an SCMI channel dynamically.
static int	scmi_transport_init (const struct device *transport)
	Perform initialization for the transport layer driver.
static int	scmi_transport_setup_chan (const struct device *transport, struct scmi_channel *chan, bool tx)
	Setup an SCMI channel.
static int	scmi_transport_send_message (const struct device *transport, struct scmi_channel *chan, struct scmi_message *msg)
	Send an SCMI channel.
static int	scmi_transport_read_message (const struct device *transport, struct scmi_channel *chan, struct scmi_message *msg)
	Read an SCMI message.
static bool	scmi_transport_channel_is_free (const struct device *transport, struct scmi_channel *chan)
	Check if an SCMI channel is free.
int	scmi_core_transport_init (const struct device *transport)
	Perfrom SCMI core initialization.

Detailed Description

SCMI Transport Layer abstraction and definitions.

Typedef Documentation

scmi_channel_cb

typedef void(* scmi_channel_cb) (struct scmi_channel *chan)

#include <zephyr/drivers/firmware/scmi/transport.h>

Callback function for message replies.

This function should be called by the transport layer driver whenever a reply to a previously sent message has been received. Its purpose is to notifying the SCMI core of the reply's arrival so that proper action can be taken.

Parameters

chan	pointer to SCMI channel on which the reply arrived

Function Documentation

scmi_core_transport_init()

int scmi_core_transport_init

(

const struct device *

transport

)

#include <zephyr/drivers/firmware/scmi/transport.h>

Perfrom SCMI core initialization.

Parameters

transport

pointer to the device structure for the transport layer

Return values

0	if successful
negative	errno code if failure

scmi_transport_channel_is_free()

bool scmi_transport_channel_is_free ( const struct device * transport, struct scmi_channel * chan )

inlinestatic

#include <zephyr/drivers/firmware/scmi/transport.h>

Check if an SCMI channel is free.

Parameters

transport	pointer to the device structure for the transport layer
chan	pointer to SCMI channel the query is to be performed on

Return values

0	if successful
negative	errno code if failure

scmi_transport_init()

int scmi_transport_init ( const struct device * transport )

inlinestatic

#include <zephyr/drivers/firmware/scmi/transport.h>

Perform initialization for the transport layer driver.

The transport layer driver can't be initialized directly (i.e via a call to its init() function) during system initialization. This is because the macro used to define an SCMI transport places scmi_core_transport_init() in the init section instead of the driver's init() function. As such, scmi_core_transport_init() needs to call this function to perfrom transport layer driver initialization if required.

This operation is optional.

Parameters

transport

pointer to the device structure for the transport layer

Return values

0	if successful
negative	errno code if failure

scmi_transport_read_message()

int scmi_transport_read_message ( const struct device * transport, struct scmi_channel * chan, struct scmi_message * msg )

inlinestatic

#include <zephyr/drivers/firmware/scmi/transport.h>

Read an SCMI message.

Parameters

transport	pointer to the device structure for the transport layer
chan	pointer to SCMI channel on which the message is to be read
msg	pointer to message the caller wishes to read

Return values

0	if successful
negative	errno code if failure

scmi_transport_request_channel()

struct scmi_channel * scmi_transport_request_channel ( const struct device * transport, uint32_t proto, bool tx )

inlinestatic

#include <zephyr/drivers/firmware/scmi/transport.h>

Request an SCMI channel dynamically.

Whenever the SCMI transport layer driver doesn't support static channel allocation, the SCMI core will try to bind a channel to a protocol dynamically using this function. Note that no setup needs to be performed on the channel in this function as the core will also call the channel setup() function.

Parameters

transport	pointer to the device structure for the transport layer
proto	ID of the protocol for which the core is requesting the channel
tx	true if the channel is TX, false if RX

Return values

pointer	to SCMI channel that's to be bound to the protocol
NULL	if operation was not successful

scmi_transport_send_message()

int scmi_transport_send_message ( const struct device * transport, struct scmi_channel * chan, struct scmi_message * msg )

inlinestatic

#include <zephyr/drivers/firmware/scmi/transport.h>

Send an SCMI channel.

Send an SCMI message using given SCMI channel. This function is not allowed to block.

Parameters

transport	pointer to the device structure for the transport layer
chan	pointer to SCMI channel on which the message is to be sent
msg	pointer to message the caller wishes to send

Return values

0	if successful
negative	errno code if failure

scmi_transport_setup_chan()

int scmi_transport_setup_chan ( const struct device * transport, struct scmi_channel * chan, bool tx )

inlinestatic

#include <zephyr/drivers/firmware/scmi/transport.h>

Setup an SCMI channel.

Before being able to send/receive messages, an SCMI channel needs to be prepared, which is what this function does. If it returns successfully, an SCMI protocol will be able to use this channel to send/receive messages.

Parameters

transport	pointer to the device structure for the transport layer
chan	pointer to SCMI channel to be prepared
tx	true if the channel is TX, false if RX

Return values

0	if successful
negative	errno code if failure