Major device number?

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originally posted by 0quanquan0@Oct 18 2006, 08:57 AM

how can i know which major device number are occupied by the kernel, and which can be used by the programmer?

thanks.

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linux-2.6.x/Documentation/devices.txt

Thanks you, hippo. I have found this file, but I am a little confused, I don&#39;t know how to find useful information in it, how can I find the major number I can used?

And I have another question about register device driver:

I am studying two examples of led driver, they use different register methods,

one just uses the register_chrdev() function, but another uses devfs_register_chrdev(), devfs_mk_dir(), devfs_register() to finish register.

Can you tell me the difference betweem them?

thank you very much.

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originally posted by 0quanquan0@Oct 18 2006, 11:39 AM

thanks you, hippo. i have found this file, but i am a little confused, i don&#39;t know how to find useful information in it, how can i find the major number i can used?

and i have another question about register device driver:

i am studying two examples of led driver, they use different register methods,

one just uses the register_chrdev() function, but another uses devfs_register_chrdev(), devfs_mk_dir(), devfs_register() to finish register.

can you tell me the difference betweem them?

thank you very much.

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Look in ch3 of the (must have) book "Linux Device Driver 3rd ed."