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I've recently installed the "wl" (wifi) kernel module on my system. It's a driver that makes my Broadcom wifi card work. Unfortunately the module gets enabled at boot time (wifi light comes on), which is not what I want. I want to enable the module when I'm ready to, after the boot. To do this, I would run

$ sudo modprobe wl

Could you suggest which boot-time files on the system might be enabling the module please? Then I can edit the file and remove the command.

Alternatively, I wonder if "wl" is being loaded at the kernel level? If so, how do I disable "wl" in that case? (*As if I've got the faintest idea what I'm talking about).

I've looked at the following boot-time files, but NONE of them load the "wl" module:

/etc/modules  
/etc/rc.local  
/etc/init.d/knoppix-autoconfig
/boot/grub/menu.lst  
/etc/inittab

I installed "wl" on the system by installing the package "broadcom-sta-dkms", using Synaptic package manager. So I believe that a program called "dkms" may be RESPONSIBLE FOR adding the boot-time command somewhere, that loads the "wl" module.

From watching the screen when I boot the system, I see that the wifi light on the laptop comes on quite early in the boot sequence. This is WHEN the "wl" module is loaded.

The wifi light comes on round about when the boot screen shows the line "Run level n", where I think "n" is either 1, 2, or 5. It goes passed too fast for me to be sure of the number.

As far as I know, the installation of broadcom-sta-dkms above hasn't compiled a new kernel.

Re above reference to /etc/init.d/knoppix-autoconfig. This is a shell script that does "Auto-configuration and setup for Knoppix". It's there because my system is actually the "Knoppix live DVD" installed on hard disc. I believe that such boot-time scripts as /etc/rc5.d/ for example, are not used on this system, and that /etc/init.d/knoppix-autoconfig sees to everything.

Other than that, the system is basically Debian.

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    depends of your kernel version but check /etc/modules.conf or the directory /etc/modprobe.d/ also is possible that the udev daemon is loading the driver, so also check the /etc/udev/rules.d/ – Dany Flores Aug 10 '15 at 18:43
  • also be sure that the driver is a module and is not inside the kernel, because in this case you will have to recompile the kernel and compile the driver as module. – Dany Flores Aug 10 '15 at 18:46
  • I've checked, and there's no /etc/modules.conf file. And none of the files in /etc/modprobe.d/ load wl to my knowledge. For my own information, I would like to know exactly what IS loading the wl module at boot time. Is it a command in a file, or is it the system doing it. If it's a file, I'd like to know which file it is. If it's the system (as you say, possibly udev), I'd like to know how to find out what process IS actually doing it, and how and when it does it. – user128205 Aug 11 '15 at 18:39
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udev will automatically detect devices and load the appropriate module.

You can stop Debian from loading the wl module automatically by adding your own blacklist item in the modprobe.d directory.

As root create a file in /etc/modprobe.d that ends with the file extension .conf and inside put:

blacklist wl

You will then be able to load the module manually via the insmod wl command.

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