[Buildroot] [PATCH v4] linux-headers: allow use of headers from kernel "package" selected

[Thomas Petazzoni <thomas.petazzoni@free-electrons.com>]

Peter,

On Tue, 19 Jan 2016 09:21:49 +0100, Peter Korsgaard wrote:

>  > But it does seem weird to many users that the "linux" package provides
>  > some many possibilities for fetching/patching the kernel, and still the
>  > linux-headers package downloads a completely different kernel version,
>  > with less possibilities of using a custom version.
> 
> So perhaps we need an option to use the linux source for our kernel
> headers? It does mean that people need to jump back and forth between
> the toolchain and linux menus.

Adding the option is not the problem. The problem is that from
package/linux-headers/linux-headers.mk, you can't use variables defined
from linux/linux.mk. So all you can do in
package/linux-headers/linux-headers.mk is duplicate the logic from
linux/linux.mk that will calculate LINUX_HEADERS_{VERSION,SITE,SOURCE}
and apply the custom patches from the BR2_LINUX_KERNEL_* Config.in
values.

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com