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UART - 通用异步收发传输器

Universal Asynchronous Receiver/Transmitter,通用异步收发传输器

  • Compatible with industry-standard 16450/16550 UARTs
  • 64-Byte Transmit and receive data FIFOs
  • Supports DMA controller interface
  • Supports Software/ Hardware Flow Control
  • Supports IrDA 1.0 SIR
  • Supports RS-485 mode

模块配置

其menuconfig 的配置如下:

Kernel Setup --->
Drivers Setup --->
SoC HAL Drivers --->
UART devices --->
[*] enable uart driver
[*] enbale uart hal APIs Test command

源码结构

.
│ hal_uart.c # 驱动源码
│ platform-uart.h # 平台选择头文件
│ uart.h # 驱动私有头文件
└─platform
uart-sun20iw2p1.h # 平台特化定义

模块接口说明

头文件

#include <hal_uart.h>

返回值枚举

typedef enum
{
HAL_UART_STATUS_ERROR_PARAMETER = -4, /**< Invalid user input parameter. */
HAL_UART_STATUS_ERROR_BUSY = -3, /**< UART port is currently in use. */
HAL_UART_STATUS_ERROR_UNINITIALIZED = -2, /**< UART port has not been initialized. */
HAL_UART_STATUS_ERROR = -1, /**< UART driver detected a common error. */
HAL_UART_STATUS_OK = 0 /**< UART function executed successfully. */
} hal_uart_status_t;

波特率枚举

typedef enum
{
UART_BAUDRATE_300 = 0,
UART_BAUDRATE_600,
UART_BAUDRATE_1200,
UART_BAUDRATE_2400,
UART_BAUDRATE_4800,
UART_BAUDRATE_9600,
UART_BAUDRATE_19200,
UART_BAUDRATE_38400,
UART_BAUDRATE_57600,
UART_BAUDRATE_115200,
UART_BAUDRATE_230400,
UART_BAUDRATE_576000,
UART_BAUDRATE_921600,
UART_BAUDRATE_1000000,
UART_BAUDRATE_1500000,
UART_BAUDRATE_3000000,
UART_BAUDRATE_4000000,
UART_BAUDRATE_MAX,
} uart_baudrate_t;

UART 字长枚举

typedef enum
{
UART_WORD_LENGTH_5 = 0,
UART_WORD_LENGTH_6,
UART_WORD_LENGTH_7,
UART_WORD_LENGTH_8,
} uart_word_length_t;

UART 停止位枚举

typedef enum
{
UART_STOP_BIT_1 = 0,
UART_STOP_BIT_2,
} uart_stop_bit_t;

UART 奇偶枚举

typedef enum
{
UART_PARITY_NONE = 0,
UART_PARITY_ODD,
UART_PARITY_EVEN
} uart_parity_t;

UART 配置结构体

typedef struct
{
uart_baudrate_t baudrate;
uart_word_length_t word_length;
uart_stop_bit_t stop_bit;
uart_parity_t parity;
} _uart_config_t;

获取UART驱动的版本号

函数原型:

sunxi_hal_version_t hal_uart_get_version(int32_t dev)

参数:

  • dev:UART端口号

返回:

  • UART 驱动版本号

初始化UART驱动

函数原型:

int32_t hal_uart_init(int32_t uart_port);

参数:

  • uart_port:UART 端口号

返回:

  • 0:成功
  • 负数:失败

初始化异构AMP UART控制台

函数原型:

int32_t hal_uart_init_for_amp_cli(int32_t uart_port);

参数:

  • uart_port:UART 端口号

返回:

  • 0:成功
  • 负数:失败

卸载UART驱动

函数原型:

int32_t hal_uart_deinit(int32_t uart_port);

参数:

  • uart_port:UART 端口号

返回:

  • 0:成功
  • 负数:失败

发送数据

函数原型:

int32_t hal_uart_send(int32_t dev, const uint8_t *data, uint32_t num);

参数:

  • dev:UART 端口号
  • data:准备发送的数据buffer
  • num:buffer 大小

返回:

  • 成功发送的字节数

发送一个字符

函数原型:

int32_t hal_uart_put_char(int32_t dev, char c);

参数:

  • dev:UART 端口号
  • c:待发送的字符

返回:

  • 1:成功

接收数据

函数原型:

int32_t hal_uart_receive(int32_t dev, uint8_t *data, uint32_t num);

参数:

  • dev:UART 端口号
  • data:接收数据缓冲区
  • num:接收数据的大小

返回:

  • size:接收到的数据大小

非阻塞接收数据

函数原型:

int32_t hal_uart_receive_no_block(int32_t dev, uint8_t *data, uint32_t num, int32_t timeout);

参数:

  • dev:UART 端口号
  • data:接收数据缓冲区
  • num:接收数据的大小
  • timeout:超时时间

返回:

  • size:接收到的数据大小

接收一个字符

函数原型:

uint8_t hal_uart_get_char(int32_t dev);

参数:

  • dev:UART 端口号

返回:

  • 收到的字符值

设置 UART 工作参数

函数原型:

int32_t hal_uart_control(int32_t uart_port, int cmd, void *args);

参数:

  • uart_port:UART 端口号
  • cmd:保留
  • args: 指向 _uart_config_t 类型的结构体

返回:

  • 0:成功
  • 负数:失败

轮询接收

函数原型:

int32_t hal_uart_receive_polling(int32_t dev, uint8_t *data, uint32_t num);

参数:

  • dev:UART 端口号
  • data:接收数据缓冲区
  • num:接收数据的大小

返回:

  • size:接收到的数据大小

查看轮询接收状态

函数原型:

int32_t hal_uart_check_poll_state(int32_t dev_id, short key);

参数:

  • dev_id:UART 端口号
  • key:标志位,取值 POLLIN,POLLOUT,POLLERR

返回:

  • UART 当前的接收状态

执行唤醒处理函数

函数原型:

int32_t hal_uart_poll_wakeup(int32_t dev_id, short key);

参数:

  • dev_id:UART 端口号
  • key:标志位,取值 POLLIN,POLLOUT,POLLERR

返回:

  • 回调函数执行返回值

注册唤醒处理函数

函数原型:

int32_t hal_uart_register_poll_wakeup(poll_wakeup_func poll_wakeup);

参数:

  • poll_wakeup:回调函数

返回:

  • 0

设置硬件流控

函数原型:

void hal_uart_set_hardware_flowcontrol(uart_port_t uart_port);

参数:

  • uart_port:UART 端口号

返回:

禁用硬件流控

函数原型:

void hal_uart_disable_flowcontrol(uart_port_t uart_port);

参数:

  • uart_port:UART 端口号

返回:

设置 UART 回环

函数原型:

void hal_uart_set_loopback(uart_port_t uart_port, bool enable);

参数:

  • uart_port:UART 端口号
  • enable:是否开启

返回:

使能 RX 中断

函数原型:

int32_t hal_uart_enable_rx(int32_t uart_port);

参数:

  • uart_port:UART 端口号

返回:

  • 0

失能 RX 中断

函数原型:

int32_t hal_uart_disable_rx(int32_t uart_port);

参数:

  • uart_port:UART 端口号

返回:

  • 0

模块使用范例

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>

#include <hal_log.h>
#include <hal_cmd.h>
#include <hal_timer.h>
#include <hal_uart.h>

static void cmd_usage(void)
{
printf("Usage:\n"
"\t hal_uart <port> <baudrate>\n");
}

int cmd_test_uart(int argc, char **argv)
{
uint8_t tbuf[6] = {"hello"};
uint8_t rbuf[10] = {0};
uart_port_t port;
uint32_t baudrate;
_uart_config_t uart_config;
int i;

hal_log_info("Testing UART in loopback mode");

if (argc != 3) {
cmd_usage();
return -1;
}

port = strtol(argv[1], NULL, 0);
baudrate = strtol(argv[2], NULL, 0);

if(CONFIG_CLI_UART_PORT == port){
hal_log_info("uart0 can't test, please use other port!");
return -1;
}
memset(rbuf, 0, 10 * sizeof(uint8_t));

switch (baudrate) {
case 4800:
uart_config.baudrate = UART_BAUDRATE_4800;
break;

case 9600:
uart_config.baudrate = UART_BAUDRATE_9600;
break;

case 115200:
uart_config.baudrate = UART_BAUDRATE_115200;
break;

case 1500000:
uart_config.baudrate = UART_BAUDRATE_1500000;
break;

case 4000000:
uart_config.baudrate = UART_BAUDRATE_4000000;
break;
default:
hal_log_info("Using default baudrate: 115200");
uart_config.baudrate = UART_BAUDRATE_115200;
break;
}

uart_config.word_length = UART_WORD_LENGTH_8;
uart_config.stop_bit = UART_STOP_BIT_1;
uart_config.parity = UART_PARITY_NONE;

hal_uart_init(port);
hal_uart_control(port, 0, &uart_config);
hal_uart_disable_flowcontrol(port);
hal_uart_set_loopback(port, 1);

/* send */
hal_uart_send(port, tbuf, 5);

/* loopback receive */
hal_uart_receive_no_block(port, rbuf, 5, MS_TO_OSTICK(1000));

printf("Sending:");
for (i = 0; i < 5; i++)
printf("%c", tbuf[i]);
printf("\n");

printf("Receiving:");
for (i = 0; i < 5; i++)
printf("%c", rbuf[i]);
printf("\n");

/* verify data */
for (i = 0; i < 5; i++) {
if (tbuf[i] != rbuf[i])
break;
}
if (i == 5) {
hal_log_info("Test hal_uart_init API success!");
hal_log_info("Test hal_uart_control API success!");
hal_log_info("Test hal_uart_disable_flowcontrol API success!");
hal_log_info("Test hal_uart_set_loopback API success!");
hal_log_info("Test hal_uart_send API success!");
hal_log_info("Test hal_uart_receive API success!");
hal_log_info("Test hal_uart_deinit API success!");
hal_log_info("Test uart hal APIs success!");
} else {
hal_log_info("Test uart hal APIs failed!");
}

hal_msleep(1000);
hal_uart_deinit(port);

return 0;
}

FINSH_FUNCTION_EXPORT_CMD(cmd_test_uart, hal_uart, uart hal APIs tests)

#define BUFFSIZE 4096

static void cmd_stress_usage(void)
{
printf("Usage:\n"
"\t hal_uart <port> <baudrate> <flowctrl> <loopback> <len>\n");
}

int cmd_test_uart_stress(int argc, char **argv)
{
uint8_t *tbuf = malloc(BUFFSIZE);
uint8_t *rbuf = malloc(BUFFSIZE);
uart_port_t port;
uint32_t baudrate;
_uart_config_t uart_config;
int i;
int flowctrl, loopback, testlen;

hal_log_info("Testing UART in loopback mode with stress");

if (argc != 6) {
cmd_stress_usage();
free(tbuf);
free(rbuf);
return -1;
}

port = strtol(argv[1], NULL, 0);
baudrate = strtol(argv[2], NULL, 0);
flowctrl = strtol(argv[3], NULL, 0);
loopback = strtol(argv[4], NULL, 0);
testlen = strtol(argv[5], NULL, 0);

for (i = 0; i < BUFFSIZE; i++) {
tbuf[i] = ('a' + i) & 0xff;
}
memset(rbuf, 0, BUFFSIZE * sizeof(uint8_t));

switch (baudrate) {
case 4800:
uart_config.baudrate = UART_BAUDRATE_4800;
break;

case 9600:
uart_config.baudrate = UART_BAUDRATE_9600;
break;

case 115200:
uart_config.baudrate = UART_BAUDRATE_115200;
break;

case 1500000:
uart_config.baudrate = UART_BAUDRATE_1500000;
break;

default:
hal_log_info("Using default baudrate: 115200");
uart_config.baudrate = UART_BAUDRATE_115200;
break;
}

uart_config.word_length = UART_WORD_LENGTH_8;
uart_config.stop_bit = UART_STOP_BIT_1;
uart_config.parity = UART_PARITY_NONE;

hal_uart_init(port);
hal_uart_control(port, 0, &uart_config);
printf("flow:%d, loopback:%d len:%d\n", flowctrl, loopback, testlen);
if (flowctrl)
hal_uart_set_hardware_flowcontrol(port);
else
hal_uart_disable_flowcontrol(port);

if (loopback)
hal_uart_set_loopback(port, 1);
else
hal_uart_set_loopback(port, 0);

/* send */
printf("send\n");
hal_uart_send(port, tbuf, testlen);
printf("send done\n");

printf("recv\n");
/* loopback receive */
hal_uart_receive(port, rbuf, testlen);
printf("recv done\n");

#if 0
printf("Sending:");
for (i = 0; i < testlen; i++) {
if (i % 16 == 0)
printf("\n");
printf("0x%x ", tbuf[i]);
}
printf("\n");

printf("Receiving:");
for (i = 0; i < testlen; i++) {
if (i % 16 == 0)
printf("\n");
printf("0x%x ", rbuf[i]);
}
printf("\n");
#endif

/* verify data */
for (i = 0; i < testlen; i++) {
if (tbuf[i] != rbuf[i]) {
printf("check %d fail, 0x%x != 0x%x\n", i, tbuf[i], rbuf[i]);
break;
}
}
if (i == testlen) {
hal_log_info("Test hal_uart_init API success!");
hal_log_info("Test hal_uart_control API success!");
hal_log_info("Test hal_uart_disable_flowcontrol API success!");
hal_log_info("Test hal_uart_set_loopback API success!");
hal_log_info("Test hal_uart_send API success!");
hal_log_info("Test hal_uart_receive API success!");
hal_log_info("Test hal_uart_deinit API success!");
hal_log_info("Test uart hal APIs success!");
} else {
hal_log_info("Test uart hal APIs failed!");
}

hal_msleep(1000);
hal_uart_deinit(port);
free(tbuf);
free(rbuf);

return 0;
}

FINSH_FUNCTION_EXPORT_CMD(cmd_test_uart_stress, hal_uart_stress, uart hal APIs tests)