In the readme:
"You compile this source on your system and link with a precompiled binary
file (wlc_hybrid.o_shipped) which contains the rest of the driver."
This appears to be even less free than your typical "open source" driver with
non-free firmware. Broadcom is a company to avoid. There is some limited
support for some broadcom chipsets in Trisquel though. Yours appears not to
be one of them.
However I wouldn't recommend broadcom at the moment anyway. This is because
the development team working on the free software broadcom driver advises
against it at this time.
Broadcom did announce support for "Linux" some time ago although thus far I
can't say we have seen a whole lot from it. Like others (such as AMD's ATI
chipsets) it seems to have probably been largely a publicity stunt. However
there is an alternative explanation. They just aren't putting sufficient
resources into it. There is a free software driver for some chipset(s). I'm
not sure if this has anything to do with Broadcom's support or not. If it
does we may use/recommend Broadcom in the future.
It should be noted that companies do reverse course some times. Some go from
doing a great job of supporting GNU/Linux and free software to doing a
horrible job of it (think Creative).
Then there are others who have gone from not supporting "Linux" at all to
providing excellent support.
