From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [build bug] drivers/built-in.o: In function
 `rt2x00leds_resume': : undefined reference to `led_classdev_resume'
Date: Fri, 25 Apr 2008 01:05:34 -0700 (PDT)
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From: Ingo Molnar <mingo@elte.hu>
Date: Fri, 25 Apr 2008 10:00:33 +0200

> personally i always considered this a Kconfig bug - although it's 
> probably not an easy issue to solve. (what if there are conflicts? What 
> if a driver's select choice disables another driver, without the user 
> being openly aware of this side-effect?)

It definitely is seen as a bug in the context of the alternative,
using 'depend' and then forcing people to spend a lot of time trying
to figure out what magic option they have to enable just to turn
on the driver for their wireless card.

> the patch below fixes it here but it's still kind of a band-aid - what 
> if the Kconfig structure of LEDS get modified - does that have to be 
> propagated to all LEDS using drivers? I dont think this necessity of 
> open-coded dependency resolution is maintainable in the long run.

Yes, that would be the way to work around this.

iwlwifi used LEDS and would need a similar workaround.

Maybe part of the problem is the "if NEW_LEDS" construct used
by drivers/leds/Kconfig?  Perhaps we could make this work if
NEW_LEDS appeared as an explicit dependency of the various
LEDS_* options.

Or, maybe it works to make LEDS_CLASS select NEW_LEDS.

I don't know, this is just a gigantic maze, and I'm just throwing out
random ideas.