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Note: I'm listing this problem as it is today, I'm not opposed to changing the implementation (moving the creation of the class to a common area for example) if it makes things easier... I'm just not sure how to do it. :End Note I've got two linux kernel modules and I'm trying to update the /sys entries for them. Searching around on google and other sources, I've seen lots of code along the lines of: static dev_t MyDev; static struct class *c1; static int __init start_func(void) { ... MyDev = MKDEV(nMajor, MINOR_VERSION); register_chrdev_region(MyDev, 1, MODULE_NAME); c1 = class_create(THIS_MODULE, "chardrv"); device_create(c1, NULL, MyDev, NULL, MODULE_NAME); .... And I've verified for my first module this code works, and that it correctly creates a: /sys/class/chardrv/<MODULE_NAME> entry. What I'd like to know is how do you create a device in an existing class. In other words, one of my modules created this new chardrv class, now I want my other module to be able to also register its devices under the same class. I can't call class_create() again (in the second module), because that "chardrv" class already exists... So I can run a check to see if /sys/class/chardrv exists, and this can help me decide if I need to call class_create() or not, that's not a problem. Lets put some pseudo code in here to clarify: if ( path "/sys/class/chardrv" does not exist) new_class = class_create("chardrv") else new_class = some how get class "chardrv" handle, or properties, or whatever device_create(new_class, ...) So as per this example, if my class already exists, and I just want to add my new device into it from a second module I assume I need to create a class structure and somehow populate it with the correct "chardrv class" attributes then call device

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