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From: Hubert CHAUMETTE <hubert.chaumette-A7wQCf4NAVlWk0Htik3J/w@public.gmane.org>
Subject: Re: Beginner query regarding usbhid
Date: Wed, 25 Mar 2020 16:41:38 +0100
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To: Rohit Sarkar <rohitsarkar5398-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: Oliver Neukum <oneukum-IBi9RG/b67k@public.gmane.org>, linux-usb-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-newbie-u79uwXL29TY76Z2rM5mHXA@public.gmane.org

Le 25/03/2020 15:47, Rohit Sarkar a écrit :
> I was trying to mess around with the driver that drives my mouse. I
> found out that it is usbhid. I then added a printk statement to the 
> init
> and exit function of usbhid.
> I then compiled and installed the usbhid drivers. Post that I ran
> `sudo modprobe -r usbhid` and `sudo modprobe usbhid` but couldnt 
> observe
> any logs in dmesg.
> 
> I am certain I am missing something fundamental. Could someone help me
> with this.

Hi,

Did you check whether your module was effectively loaded with lsmod?
What log level did you use in your printk statement? Depending on your
system default loglevel your logs might not be printed. A quick fix
would be to use one of the lowest levels (pr_emerg, but pr_err might
suffice).
Regards,

Hubert Chaumette