re-enable your Broadcom wireless adapter in Ubuntu 12.04

I guess this process should be totally easy, it wouldn't be necessary to use even a command, I guess, but sometimes I don't have the enough time to test things like this. Anyway, I have an HP Ultrabook with a Broadcom BCM4312 Wireless Adapter, Yesterday I turned it off using the physical switch button, some time later I tried to re-enable it using the same button - It has to work, trust me, maybe it is a bug with the driver or anything else- but I failed, so, to re-enable I did this:

1. From a terminal I type:
  sudo rfkill list all

in the list I could see my device is blocked by hardware and software

2. then type:
  rfkill unblock all

 then, push the switch button.

3. again, type:
  sudo rfkill list all

Now, at least for me, I can see the device is just blocked by software, the last step is go to the wireless icon in the right upper corner, right click on it and choose "enable wireless", now you may see your wireless button turns blue and it acquires IP from your access point.

That's it, as I told you before, for sure this is a problem with my card or I had just been missed something, I always read that this card is kind of tricky in GNU/Linux, futhermore it is really old -this laptop has more than 5 years- , but if you have a system like this, it might be helpful

Time to go, see you!