[已解决]完成量等待代码执行太慢,而中断发送太快导致完成量提前完成怎么办?

发布于 2024-06-19 23:33:24 浏览：448 订阅该版

- 在调试STM32 硬件I2C驱动,使用中断方式收发I2C数据
- 代码在`bsp\stm32\libraries\HAL_Drivers\drivers\drv_hard_i2c.c`中,以下是简洁代码

```c
//发送I2C数据,使用中断方式
static rt_ssize_t stm32_i2c_master_xfer(struct rt_i2c_bus_device *bus,
                                        struct rt_i2c_msg msgs[],
                                        rt_uint32_t num)
{
	 HAL_I2C_Master_Seq_Transmit_IT(handle, (msg->addr<<1), msg->buf, msg->len, mode);
	 if (rt_completion_wait(completion, timeout) != RT_EOK)
	 {
		 LOG_D("transmit time out");
		 goto out;
	}
}

//中断回调中
void HAL_I2C_MasterTxCpltCallback(I2C_HandleTypeDef *hi2c)
{
    struct stm32_i2c *i2c_drv = rt_container_of(hi2c, struct stm32_i2c, handle);
    rt_completion_done(&i2c_drv->completion);
}
```

- 发现永远打印I2C传输超时,调整timeout时间怎么调大都没用;
- 打断点调试发现,`rt_completion_wait`执行到一半时,中断就已经触发了`rt_completion_done`;导致永远是超时的;

```c
rt_err_t rt_completion_wait(struct rt_completion *completion,
                            rt_int32_t            timeout)
{
    rt_err_t result;
    rt_base_t level;
    rt_thread_t thread;
    RT_ASSERT(completion != RT_NULL);

//! 这里就触发中断了
    RT_DEBUG_SCHEDULER_AVAILABLE(timeout != 0);
}
```

- 问题来了,这应该该驱动代码还是完成量代码?

- 是完成量wait代码添加中断屏蔽呢?还是驱动中发送前后添加中断屏蔽?