Re: [RFC: 2.6 patch] fix ISDN_CAPI<->ISDN_DIVAS

[Adrian Bunk <bunk@stusta.de>]

On Sat, Mar 24, 2007 at 02:49:42PM +0100, Armin Schindler wrote:
> On Sat, 24 Mar 2007, Adrian Bunk wrote:
> > Randy Dunlap reported in kernel Bugzilla #8241 the following compile 
> > error with CONFIG_ISDN_CAPI=m, CONFIG_ISDN_DIVAS=y:
> > 
> > <--  snip  -->
> > 
> > ...
> > WARNING: "DIVA_DIDD_Read" [drivers/isdn/hardware/eicon/divacapi.ko] undefined!
> > WARNING: "DIVA_DIDD_Read" [drivers/isdn/hardware/eicon/diva_mnt.ko] undefined!
> > WARNING: "DIVA_DIDD_Read" [drivers/isdn/hardware/eicon/diva_idi.ko] undefined!
> > WARNING: "proc_net_eicon" [drivers/isdn/hardware/eicon/diva_idi.ko] undefined!
> > make[1]: *** [__modpost] Error 1
> > 
> > <--  snip  -->
> > 
> > 
> > Kconfig contains the following strange thing:
> > 
> > menu "Active Eicon DIVA Server cards"
> >         depends on NET && ISDN && ISDN_CAPI!=n
> > 
> > 
> > It seems that except for ISDN_DIVAS_DIVACAPI (that already has a proper 
> > dependency), nothing here actually requires ISDN_CAPI?
> 
> Not quite true. Yes, the base modules for the divas driver do not require 
> ISDN_CAPI, but without ISDN_CAPI it doesn't make any sense.

Let me try to understand this:

Does it make sense to have CONFIG_ISDN_DIVAS=y, CONFIG_ISDN_CAPI=m?
And do CONFIG_ISDN_DIVAS=y/m, CONFIG_ISDN_DIVAS_DIVACAPI=n 
configurations make sense?

If not, what about:
- let ISDN_DIVAS depend on ISDN_CAPI and
- enable ISDN_DIVAS_DIVACAPI unconditionally (and perhaps even build 
                                              it into the divas module)?

> The patch below (go into /hardware even for non ISDN_CAPI) is wrong. The
> subdir /hardware was created for new drivers using CAPI. So it is correct to
> go there when ISDN_CAPI != n only.
> 
> I don't understand the warnings above. The symbols are exported by divas 
> modules, so why is it causing warnings? There have been no change in the 
> divas modules for this. Any change in the kernel module creation structure
> which may causing this?

These aren't warnings, these are errors.

Due to
  obj-$(CONFIG_ISDN_CAPI)                    += hardware/

hardware/ isn't visited with CONFIG_ISDN_CAPI=m when building vmlinux.

This means the modules were built, but the static code they were using 
wasn't linkd into the kernel.

This might not have occured before since CONFIG_ISDN_CAPI=m, 
CONFIG_ISDN_DIVAS=y is an unusual configuration.

> Armin
>...

cu
Adrian

-- 

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