|Linux| How to create a device node?

How to create a device in /dev automatically

Ans: device_create

- Include the header file linux/device.h and linux/kdev_t.h

    static struct class c_dev;
    static struct dev_t dev;

- Add the below API 's inside __init fuction of the driver

    cl = class_create(THIS_MODULE ,"x");

    where x - Name to be displayed inside /sys/class/ when driver is loaded.

 - Use device_create () kernel api with device_create(cl, NULL, dev, NULL, "d");

    where d - device file to be created under /dev.

 - Use cdev_init to initialize

 - Use cdev_add to add the device to the /dev list

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