On Wednesday 07 May 2014 11:35:12 Eric Nelson wrote: > > 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. I haven't done it myself, but I'm told that you can do it from the boot script as normal commands, without having to modify the source. Arnd -- 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
