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I'm working with a LeopardBoard DM368 and I want to enable some video hardware. The relevant modules are vpfe-capture, isif, and tvp7002.

I've written a defconfig file with what I believe to be the correct set of CONFIG_FOO parameters for everything to work. Judging by the dependencies appearing in the various Kconfig files, I believe I've done everything correctly, but I can't seem to prevent kconf from discarding CONFIG_ISIF and CONFIG_VPFE_CAPTURE.

My very ugly alternative is to go in and start manually hacking makefiles. That works to pick up the modules I want, but it's obviously inconsistent with the design and intent of the Kconfig system, and would break any tools like "make gconfig".

make has a "-d" verbosity flag that explains how it is processing dependencies. Is there anything similar for kconf, where I could get it to explain why it's not giving me the two CONFIGs I'm trying to get?

artless noise
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Will Ware
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    In `menuconfig`, you can type a '/' character to search names. When you do this, it shows a **SELECTS** and **DEPENDS** lines and gives currently selected options for each dependency. You need to look at the **DEPENDS** list and keep iterating. – artless noise Aug 23 '14 at 16:08

2 Answers2

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Sorry if this is a bit pluggish. :)

I've written a Python library for working with Kconfig-based configuration systems (Kconfiglib). It allows for easy inspection of symbol dependencies (see Symbol.__str__(), invoked e.g. by printing a Symbol) and lets you set values and evaluate arbitrary expressions in the context of a configuration, which can be handy to figure out what's going on.

Ulf Magnusson
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  • No problem with the plug, a Python library for this makes me happy, and if I'd stuck with the problem longer I'd probably have written one myself. I'm on to a different piece of hardware where I'm not dealing with Kconfig, but I don't think I've seen the last of it and I'm glad to know this exists. Thanks! – Will Ware Jan 02 '13 at 19:42
  • It'd be nice if it were possible to use it with other projects using Kconfig, e.g. [linux-backports](https://backports.wiki.kernel.org) and [u-boot](http://www.denx.de/wiki/U-Boot). – pevik Jun 17 '15 at 14:36
  • It seems [it's possible to use it with u-boot](http://www.spinics.net/lists/linux-kbuild/msg11303.html) :-). – pevik Jun 18 '15 at 05:53
  • It seems that kconfiglib is not maintained, and cannot be used on latest Linux release. – youfu Jul 05 '23 at 07:03
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You could try running make V=2 oldconfig and see if that shows any additional clues.

MikeK
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