uart.h

/*
 * Copyright (C) 2026 Kamil Lulko <kamil.lulko@gmail.com>
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 * This file is part of oveRTOS.
 */
 
#ifndef OVE_UART_H
#define OVE_UART_H
 
#include "ove/types.h"
#include "ove_config.h"
#include "ove/storage.h"
 
#ifdef __cplusplus
extern "C" {
#endif
 
/* ── Enums ───────────────────────────────────────────────────────── */
 
typedef enum {
    OVE_UART_PARITY_NONE = 0,
    OVE_UART_PARITY_ODD  = 1,
    OVE_UART_PARITY_EVEN = 2,
} ove_uart_parity_t;
 
typedef enum {
    OVE_UART_STOP_1   = 0,
    OVE_UART_STOP_1_5 = 1,
    OVE_UART_STOP_2   = 2,
} ove_uart_stop_t;
 
typedef enum {
    OVE_UART_FLOW_NONE    = 0,
    OVE_UART_FLOW_RTS_CTS = 1,
} ove_uart_flow_t;
 
/* ── Configuration ───────────────────────────────────────────────── */
 
struct ove_uart_cfg {
    unsigned int      instance;     
    uint32_t          baudrate;     
    uint8_t           data_bits;    
    ove_uart_parity_t parity;       
    ove_uart_stop_t   stop_bits;    
    ove_uart_flow_t   flow_control; 
    size_t            rx_buf_size;  
};
 
#ifdef CONFIG_OVE_UART
 
/* ── Lifecycle ───────────────────────────────────────────────────── */
 
int  ove_uart_init(ove_uart_t *uart, ove_uart_storage_t *storage,
           void *rx_buf, const struct ove_uart_cfg *cfg);
 
void ove_uart_deinit(ove_uart_t uart);
 
#ifdef OVE_HEAP_UART
int  ove_uart_create(ove_uart_t *uart, const struct ove_uart_cfg *cfg);
void ove_uart_destroy(ove_uart_t uart);
#elif !defined(__ZIG_CIMPORT__)
#define ove_uart_create(puart, cfg) \
    ({ static ove_uart_storage_t _ove_stor_; \
       static uint8_t _ove_buf_[(cfg)->rx_buf_size]; \
       ove_uart_init((puart), &_ove_stor_, _ove_buf_, (cfg)); })
#define ove_uart_destroy(uart) ove_uart_deinit(uart)
#endif
 
/* ── Operations ──────────────────────────────────────────────────── */
 
int  ove_uart_write(ove_uart_t uart, const void *data, size_t len,
            uint32_t timeout_ms, size_t *bytes_written);
 
int  ove_uart_read(ove_uart_t uart, void *buf, size_t len,
           uint32_t timeout_ms, size_t *bytes_read);
 
size_t ove_uart_bytes_available(ove_uart_t uart);
 
int  ove_uart_flush(ove_uart_t uart);
 
/* ── ISR helper (called by backend, not by application code) ─────── */
 
void ove_uart_rx_isr_push(ove_uart_t uart, const void *data, size_t len);
 
#else /* !CONFIG_OVE_UART */
 
static inline int  ove_uart_create(ove_uart_t *u, const struct ove_uart_cfg *c) { (void)u; (void)c; return OVE_ERR_NOT_SUPPORTED; }
static inline void ove_uart_destroy(ove_uart_t u) { (void)u; }
static inline int  ove_uart_write(ove_uart_t u, const void *d, size_t l, uint32_t t, size_t *bw) { (void)u; (void)d; (void)l; (void)t; (void)bw; return OVE_ERR_NOT_SUPPORTED; }
static inline int  ove_uart_read(ove_uart_t u, void *b, size_t l, uint32_t t, size_t *br) { (void)u; (void)b; (void)l; (void)t; (void)br; return OVE_ERR_NOT_SUPPORTED; }
static inline size_t ove_uart_bytes_available(ove_uart_t u) { (void)u; return 0; }
static inline int  ove_uart_flush(ove_uart_t u) { (void)u; return OVE_ERR_NOT_SUPPORTED; }
static inline void ove_uart_rx_isr_push(ove_uart_t u, const void *d, size_t l) { (void)u; (void)d; (void)l; }
 
#endif /* CONFIG_OVE_UART */
 
#ifdef __cplusplus
}
#endif
 
#endif /* OVE_UART_H */