Re: [linuxtv-commits] [hg:v4l-dvb] Fix FW_LOADER depencency atv4l/dvb

From: Mauro Carvalho Chehab
Date: Tue May 06 2008 - 11:43:18 EST


On Tue, 6 May 2008 10:54:02 -0400
"Michael Krufky" <mkrufky@xxxxxxxxxxx> wrote:

> Mauro,
>
> I disagree with this change.

So, propose another way to fix. Without this patch, if HOTPLUG = 'n', several
drivers will break.

Sorry, but I can't see any other solution (in fact, I tested "select HOTPLUG",
but this caused circular dependencies loops).

The way "select" works is simple: You need to manually add all "depends on"
from the original symbol into the one that adds "select". I don't like this way
(and I'm currently questioning this at LKML), but while people don't decide to
implement "select" on another way (or to write a different tag for this, as
proposed by Sam), the proper fix is the one I've proposed.

If you have a better proposal, please, feel free to send it. If you have a
better fix, I'll revert this one.

> It looks like you are attempting to workaround a Kbuild bug

It is not a Kbuild bug, but the way Kbuild were implemented. This is what is
written at kbuild/kconfig-language.txt:

" select should be used with care. select will force
a symbol to a value without visiting the dependencies.
By abusing select you are able to select a symbol FOO even
if FOO depends on BAR that is not set.
In general use select only for non-visible symbols
(no prompts anywhere) and for symbols with no dependencies.
That will limit the usefulness but on the other hand avoid
the illegal configurations all over.
kconfig should one day warn about such things."

Cheers,
Mauro
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/