On Mon, Jan 10, 2022 at 4:42 AM Yu Tu <yu.tu@xxxxxxxxxxx> wrote: > > Deprecated, don't use anymore because legacy amlogic,meson-gx-uart > compatible. Don't differentiate between GXBB, GXL and G12A which > have different revisions of the UART IP. So it's split into > GXBB,GXL and G12A. You are breaking compatibility. If your dts is updated to use the new compatible, then a kernel without the change will not work anymore. It worked before without understanding the changes you are making. It should continue to. A compatible value like this would accomplish what you want: "amlogic,meson-gxbb-uart", "amlogic,meson-gx-uart", "amlogic,meson-ao-uart" A new kernel will match on "amlogic,meson-gxbb-uart" or "amlogic,meson-gx-uart" depending if the dtb is updated or not. An old kernel will continue to match on "amlogic,meson-gx-uart". If you are going to go breaking things, the power domain distinction in the compatible is odd... Rob