【求助】【请教linux驱动】【pwm子系统】【设备树devm_of_pwm_get】【卡死】

[shiguojie19892]

请教：设备树设置了一个PWM引脚时，工作正常，但是设置两个PWM引脚，linux加载驱动就死机了，不明觉厉。设备树根目录和iomuxc：

        fs_pwm {
                compatible = "fs_pwm";
                pinctrl-names = "default";
                pinctrl-0 = <&pinctrl_fspwm>;
                pwm_power {
                        pwm-names = "pwm_power";
                        pwms =         <&pwm1 0 50000>;
                };
                pwm_motor {
                        pwm-names = "pwm_motor";
                        pwms =         <&pwm2 0 50000>;
                };

        };

        pinctrl_fspwm:fspwmgrp {
                fsl,pins = <
                        MX6UL_PAD_LCD_DATA00__PWM1_OUT          0x1b0b0        /*/pwm1&motor pwm*/        
                        MX6UL_PAD_LCD_DATA01__PWM2_OUT          0x1b0b0        /*/pwm1&motor pwm*/        
                >;

读取节点：

struct pwm_device        *pwm_power_dev = NULL;  //定义pwm设备结构体
struct pwm_device   *pwm_motor_dev = NULL;
/*精简版 prob函数*/
static int pwm_power_probe_new(struct platform_device *pdev)
{
        int ret = 0;
        struct device_node * child;
        struct device_node * child2;
        struct device *dev = &pdev->dev;
        printk("match success \n");

        child = of_get_next_child(dev->of_node, NULL);
    printk("\"%s\"'s child: \"%s\"\n", dev->of_node->full_name, child->full_name);
    printk("%s %s line %d\r\n"__FILE__, __FUNCTION__, __LINE__);
    if(NULL == child)
    {
        printk("of_get_next_child error\r\n");
    }
        if (child)
        {
                pwm_power_dev = devm_of_pwm_get(dev, child, NULL);
                if (IS_ERR(pwm_power_dev)) 
                {
                        printk(KERN_ERR" pwm_power_dev,get pwm  error!!\n");
                        return -1;
                }
        
        //pwm_motor_dev = devm_of_pwm_get(dev, chile, )
        }
        else
        {
                printk(KERN_ERR" pwm_power_dev of_get_next_child  error!!\n");
                return -1;
        }

        child2 = of_get_next_child(dev->of_node, child);
    
    printk("\"%s\"'s child2: \"%s\"\n", dev->of_node->full_name, child2->full_name);
    printk("\"%s\"'s child2: \"%s\"\n", dev->of_node->full_name, child2->full_name);
    printk("\"%s\"'s child2: \"%s\"\n", dev->of_node->full_name, child2->full_name);
    printk("%s %s line %d\r\n"__FILE__, __FUNCTION__, __LINE__);
    if(NULL == child2)
    {
        printk("of_get_next_child2 error\r\n");
    }
        if (child2)
        {
        if (IS_ERR(child2)) 
                {
                        printk(KERN_ERR" of_get_next_child,child2  error!!\n");
                        return -1;
                }

        printk("\"%s\"'s devm_of_pwm_get: \"%s\"\n", dev->of_node->full_name, child2->full_name);
pwm_motor_dev = devm_of_pwm_get(dev, child2, NULL);//****这句代码死机，不再往下运行

                if (IS_ERR(pwm_motor_dev)) 
                {
                        printk(KERN_ERR" pwm_power_dev,get pwm  error!!\n");
                        return -1;
                }
        }
        else
        {
                printk(KERN_ERR" pwm_power_dev of_get_next_child  error!!\n");
                return -1;
        }

    printk("set pwm_power...\r\n");

        /*配置频率100KHz 占空比80%*/
        ret = pwm_config(pwm_power_dev, 1000, 5000);
    printk("ret:%d\r\n", ret);
        /*反相 频率100KHz 占空比20%*/
        ret = pwm_set_polarity(pwm_power_dev, PWM_POLARITY_INVERSED);
    printk("ret:%d\r\n", ret);
        ret = pwm_enable(pwm_power_dev);
    printk("ret:%d\r\n", ret);

    printk("set pwm_motor...\r\n");
        /*配置频率100KHz 占空比80%*/
        ret = pwm_config(pwm_motor_dev, 1000, 5000);
    printk("ret:%d\r\n", ret);
        /*反相 频率100KHz 占空比20%*/
        ret = pwm_set_polarity(pwm_motor_dev, PWM_POLARITY_NORMAL);
    printk("ret:%d\r\n", ret);
        ret = pwm_enable(pwm_motor_dev);
    printk("ret:%d\r\n", ret);

        return ret;
}

[shiguojie19892]

没有报错，只是运行到上面代码54行，打印了54行的消息后，控制台就卡死不动了，不能输出、不能输入，同时pwm只是启动了第一个（频率、占空比也是对的 200Khz，80%占空比），下面的pwm没有启动。

[shiguojie19892]

引用 1 楼 yoveldf 的回复:

打印信息呢？报啥错误

这次运行到使能pwm_motor_dev处就卡死了。

[yoveldf]

pwm_enable跟进去加打印信息看看 看到哪步错了，pwm的这种加法我也不太确定

[yoveldf]

打印信息呢？报啥错误

[shiguojie19892]

好的，谢谢你！

[shiguojie19892]

引用 4 楼 yoveldf 的回复:

pwm_enable跟进去加打印信息看看 看到哪步错了，pwm的这种加法我也不太确定

没有启动pwm2时钟，导致卡死

[yoveldf]

引用 6 楼 shiguojie19892 的回复:

引用 4 楼 yoveldf 的回复:

pwm_enable跟进去加打印信息看看 看到哪步错了，pwm的这种加法我也不太确定

没有启动pwm2时钟，导致卡死

建议你去看下pwm2 以及pinctrl_fspwm这两个具体是怎么定义的，如果解决不了，那就把pwm2参考pwm方式独立出来定义，这样应该就不会存在问题啦