HAL Communication Interface

A communication interface is represented by chi_interface_t and exposes open, close, read, and write methods for UART, SPI, etc.

typedef bool (*chi_interface_callback_t)(const chi_interface_t *iface)

Callback function type for asynchronous interface operations.

Param iface:: Pointer to the interface instance.
Return:: true if the operation was successful, false otherwise.

int iface_open(const chi_interface_t *iface)

Wrapper functions for interface operations.

These functions call the corresponding function pointers in the chi_interface_api structure.

Parameters:: iface – Pointer to the interface instance
Returns:: int Return 0 on success, negative value on failure.

int iface_close(const chi_interface_t *iface)

Wrapper functions for interface operations.

These functions call the corresponding function pointers in the chi_interface_api structure.

Parameters:: iface – Pointer to the interface instance.
Returns:: int Return 0 on success, negative value on failure.

ssize_t iface_read(const chi_interface_t *iface, void *buffer, uint32_t size, chi_interface_callback_t cb)

Wrapper functions for interface operations.

These functions call the corresponding function pointers in the chi_interface_api structure.

Parameters:

iface – Pointer to the interface instance.
buffer – Pointer to the buffer for incoming data.
size – Number of bytes to read.
cb – Callback when the operation completes.

Returns:

ssize_t Number of bytes read on success, negative on failure.

ssize_t iface_write(const chi_interface_t *iface, const void *buffer, uint32_t size, chi_interface_callback_t cb)

Wrapper functions for interface operations.

These functions call the corresponding function pointers in the chi_interface_api structure.

Parameters:

iface – Pointer to the interface instance.
buffer – Pointer to the data to send.
size – Number of bytes to write.
cb – Callback when the operation completes.

Returns:

ssize_t Number of bytes written on success, negative on failure.

int iface_flush(const chi_interface_t *iface)

Wrapper function to flush the interface buffers.

This function calls the corresponding function pointer in the chi_interface_api structure.

Parameters:: iface – Pointer to the interface instance.
Returns:: int Return 0 on success, negative value on failure.

struct chi_interface_t

#include <interface_api.h>

Communication interface instance.

This structure represents a generic communication interface (e.g. UART, SPI) and holds the API pointer, the MMIO base, and a driver‑specific configuration pointer.

Public Members

const chi_interface_api_t *api: Function pointers for this interface.

uintptr_t base: MMIO base address (if applicable).

void *cfg: Driver‑specific configuration.

struct chi_interface_api

#include <interface_api.h>

API structure defining function pointers for communication interfaces.

Forward declaration of chi_interface_api_t.

This structure contains the open, close, read, and write function pointers, enabling a standardized interface for UART, SPI, etc.

Public Members

int (*open)(const chi_interface_t *iface)

Opens the interface.

This function initializes the hardware and prepares it for use.

Param iface:: Pointer to the interface instance.
Return:: 0 on success, negative value on failure.

int (*close)(const chi_interface_t *iface)

Closes the interface.

This function releases any resources held by the interface.

Param iface:: Pointer to the interface instance.
Return:: 0 on success, negative value on failure.

ssize_t (*read)(const chi_interface_t *iface, void *buffer, uint32_t size, chi_interface_callback_t cb)

Reads data from the interface.

Performs an asynchronous or blocking read, depending on the driver.

Param iface:: Pointer to the interface instance.
Param buffer:: Pointer to the buffer for incoming data.
Param size:: Number of bytes to read.
Param cb:: Callback when the operation completes.
Return:: Number of bytes read on success, negative on failure.

ssize_t (*write)(const chi_interface_t *iface, const void *buffer, uint32_t size, chi_interface_callback_t cb)

Writes data to the interface.

Performs an asynchronous or blocking write, depending on the driver.

Param iface:: Pointer to the interface instance.
Param buffer:: Pointer to the data to send.
Param size:: Number of bytes to write.
Param cb:: Callback when the operation completes.
Return:: Number of bytes written on success, negative on failure.

int (*flush)(const chi_interface_t *iface)

Flushes the interface buffers.

Param iface:: Pointer to the interface instance.
Return:: 0 on success, negative value on failure.