[yocto] Conditional patches on kernel depending on board, how to maintain?

[Nicolas Dechesne]

On Thu, Jun 12, 2014 at 1:54 PM, Daniel Hilst Selli
<danielhilst at gmail.com> wrote:
> I have a SoM which will be used on several boards, this SoM has a base
> kernel for it, with its board-*.c file. In each board I may have different
> peripherals, so I have to patch the same board-*.c file depending on my
> target board, and that patches may be conflicting one each other. For
> example, I could have a RF on first SPI bus on one board, and on another
> board a SD card on same first SPI bus.
>
> So basically I will have a different kernel(uImage) and rootfs (with kernel
> modules) for each board.
>
> I think to create a layer for each target board, with the linux-SoM.bbappend
> including the patches for that board..., so I enable the layer depending on
> target board I'm creating, but is too much file editions, or have a build
> directory for each target board, enabling the right layer on each
> local.conf, but this means mantaining build directories, or at last
> local.conf, which doesn't seem a good idea for me...
>
> Would be possible to do this relying only new layers and its configurations?
>

you can do:

SRC_URI_append_som1 = " file://som1.patch"

assuming som1 is a valid machine name (e.g. you have conf/machines/som1.conf)

you can do all builds with 1 layer, and 1 recipe for the kernel, with
many such lines.