Question

在我的代码中disable_irq似乎无法真正禁用irq，我有以下代码

rc  = devm_request_threaded_irq(&client->dev, irq, NULL, 
        name_for_ask_question_irq_handler,
        IRQF_ONESHOT | IRQF_TRIGGER_FALLING, client->name, data);
if (rc < 0) {
    dev_err(&client->dev, "request irq failed \n");
    return rc;
}

/* IRQ handler threadeded, this can (and will) sleep */
static irqreturn_t name_for_ask_question_irq_handler(int irq, void *dev)
{
    struct touch_point_data *pdata = dev;

    dev_err(&pdata->client->dev, "%s:%d irq handler \n", __func__, __LINE__);

    return IRQ_HANDLED;
}

static ssize_t wakeup_i2c_store(struct device *dev,
                struct device_attribute *attr,
                const char *buf, size_t size)
{
    struct touch_point_data *pdata = dev_get_drvdata(dev);

    if (buf[0] == '1') {
        disable_irq(pdata->client->irq);
        gpiod_direction_output(pdata->gpiod_irq, 0);
        udelay(100);
        gpiod_direction_output(pdata->gpiod_irq, 1);
        udelay(100);
        gpiod_direction_output(pdata->gpiod_irq, 0);
        udelay(100);
        gpiod_direction_output(pdata->gpiod_irq, 1);
        udelay(100);
        gpiod_direction_input(pdata->gpiod_irq);
        dev_err(&pdata->client->dev, "%s:%d disable irq \n", __func__, __LINE__);
    } else if (buf[0] == '2') {
        enable_irq(pdata->client->irq);
        dev_err(&pdata->client->dev, "%s:%d enable irq \n", __func__, __LINE__);
    }

    return size;
}

and then i get following result:

enter image description here

我很困惑，为什么disable_irq不能真正掩盖中断，看来这种功能只会延迟IRQ，并且在enable_irq之后仍会调用irq_handler。有谁知道发生了什么事？

Answer 1

延迟中断的处理直到重新启用才是“屏蔽”中断的含义。这正是disable_irq() / enable_irq()的工作方式。

如果您想忽略某些中断，只需将该逻辑放在中断处理程序中即可。

似乎disable_irq不能真正掩盖中断

1 个答案: