AMAZING! It works perfectly now, thanks :)! It was the setting of the BIOS. The procedure was:

1. In the BIOS, deactivate the "secure mode"
2. install the RPMfusion repositories (free and non-free)
3. install akmod-wl
4. install kernel-devel (I took the x86_64)
5. as root create a file: asus-wifi.conf in /etc/modprobe.d/ with the following string: options asus_nb_wmi wapf=1
6. #sudo akmods (to update to the actual kernel)
7. reboot
8. enjoy your wifi :)
9. Don't forget to bless admin aeperezt before you go to sleep!

Now I do: I've done this

# dnf install kernel-devel

I rebooted and still nothing

I removed the packages above and installed again only akmod-wl, and the situation is now the following:

# dnf install akmod-wl
 
rpm -qa | grep -- -wl
 
broadcom-wl-6.30.223.248-2.fc22.noarch
akmod-wl-6.30.223.248-8.fc22.1.x86_64

rebooting and doing modprobe, something changed:

# modprobe wl
modprobe: FATAL: Module wl not found.

Still no signs of life from the wireless though. Perhaps the problem is somewhere else...beside the user :)

Tnx. I guess that they should be already installed. I mean: they appear in the list above.

The wireless card is not recognized. The laptop in an asus F550LD. I've already tried several (if not all) the combinations of packages and commands that I've found on the forums but none seems to work. I guess I'm doing something wrong or I'm missing something.

This is what I know:

It's Fedora22, installed in dual-boot with win8.1, this is the kernel:

# uname -r
4.0.7-300.fc22.x86_64

And this is my wireless card:

#lspci | grep -i broadcom
03:00.0 Network controller: Broadcom Corporation BCM43142 802.11b/g/n (rev 01)

I've installed from RPMfusion the packages that are suggested:

#rpm -qa | grep -- -wl
kmod-wl-4.0.4-301.fc22.x86_64-6.30.223.248-8.fc22.1.x86_64
broadcom-wl-6.30.223.248-2.fc22.noarch
kmod-wl-6.30.223.248-8.fc22.1.x86_64
akmod-wl-6.30.223.248-8.fc22.1.x86_64
kmod-wl-4.0.7-300.fc22.x86_64-6.30.223.248-8.fc22.1.x86_64

When I run this, nothing good happens:

# modprobe wl
modprobe: ERROR: could not insert 'wl': Required key not available

# modinfo wl
filename:       /lib/modules/4.0.7-300.fc22.x86_64/extra/wl/wl.ko
license:        MIXED/Proprietary
alias:          pci:vdsvsdbc02sc80i*
depends:        cfg80211
vermagic:       4.0.7-300.fc22.x86_64 SMP mod_unload 
parm:           passivemode:int
parm:           wl_txq_thresh:int
parm:           oneonly:int
parm:           piomode:int
parm:           instance_base:int
parm:           nompc:int
parm:           intf_name:string

# rfkill list all
0: asus-wlan: Wireless LAN
    Soft blocked: no
    Hard blocked: no
1: asus-bluetooth: Bluetooth
    Soft blocked: no
    Hard blocked: no
2: hci0: Bluetooth
    Soft blocked: no
    Hard blocked: no

Somewhere I red that this might be a solution and, of course, I tried:

modprobe iwlwifi 11ndisable=1
echo options iwlwifi 11ndisable=1 > /etc/modprobe.d/iwlwifi.conf

eventually it didn't work and I removed the file iwlwifi.conf.

Additionally, since the card has no physical switch, I've red somewhere to add a file nemed: asus-wifi.conf in /etc/modprobe.d/ with the following string:

options asus_nb_wmi wapf=1

As a consequence, the LED-light of the wifi card went on...and that's the greatest success of the last 2 days :)

Is anybody having a clue of what is wrong here?

Tnx Alessio