Thanks Arnd. On 05/07/2014 11:10 AM, Arnd Bergmann wrote:
On Wednesday 07 May 2014 10:47:27 Eric Nelson wrote:It seems reasonable to tell the kernel to skip this if the WiFi driver isn't configured into the kernel (i.e. there's no point in enumerating), so I was hoping to surround this USDHC2 block with #ifdefs: https://github.com/boundarydevices/linux-imx6/blob/boundary-imx_3.10.17_1.0.0_ga/arch/arm/boot/dts/imx6qdl-nitrogen6x.dtsi#L640 The alternative aren't very nice: populate extra parts to drive these signals, or copy the DTB and strip out the unused parts The first is wasteful (and environmentally un-friendly), and the second doesn't scale very well and pollutes the Git tree.It's fine to have two .dtb files (as Olof and Jason also suggested) and you can even have both in the kernel and just pick the right one for your machine. Another option that works is to have the boot loader set up the present devices. With u-boot, you can easily manipulate the binary dtb and change a 'status="disabled"' to 'status="ok"' or vice versa for devices that are only sometimes populated, or you can change the amount of installed RAM as detected by the loader.
Easily is such a relative term ;) Thanks for the advice. Eric -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
