Hello John, On Tue, Jul 13, 2021 at 05:07:00PM -0700, John Stultz wrote: > On Tue, Oct 20, 2020 at 5:10 AM Serge Semin > <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx> wrote: > > > > In accordance with the DWC USB3 bindings the corresponding node > > name is suppose to comply with the Generic USB HCD DT schema, which > > requires the USB nodes to have the name acceptable by the regexp: > > "^usb(@.*)?" . Make sure the "snps,dwc3"-compatible nodes are correctly > > named. > > > > Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx> > > I know folks like to ignore this, but this patch breaks AOSP on db845c. :( Sorry to hear that. Alas there is no much can be done about it. DT-nodes name is a subject of DT-schema convention and as we've finally unified USB-controller nodes it shouldn't be reverted back. You can find the final USB-controller bindings in: Documentation/devicetree/bindings/usb/usb.yaml It strictly defines to have USB-nodes with names like "usb(@.*)". Reverting this patch will cause the DT-bindings check procedure failure. You can also find the naming convention defined in the latest DT spec: https://github.com/devicetree-org/devicetree-specification/releases/tag/v0.3 See also device-tree bindings requirements listed in the file: Documentation/devicetree/bindings/writing-bindings.rst It says: "DO use node names matching the class of the device. Many standard names are defined in the DT Spec. If there isn't one, consider adding it." > > In the exact same way an earlier patch broke HiKey960: > https://lore.kernel.org/lkml/CALAqxLWGujgR7p8Vb5S_RimRVYxwm5XF-c4NkKgMH-43wEBaWg@xxxxxxxxxxxxxx/ > > (which I still have to carry a revert for). > > I get that this change is useful so more dynamic userland can find > devices using consistent naming with future kernels (but doesn't the > dynamic userland have to handle the case for older kernels as well?) > But for userland that uses static configs, its painful as updating > userland to use the new node ids then causes older kernels to fail. > > I'm looking into how we might be able to probe and set the property > dynamically, but AOSP's init system is far more aligned to static > configs. > As Krzysztof said in https://lore.kernel.org/lkml/20201221210423.GA2504@kozik-lap/ and Bjorn noted in his response to your email, the only way to solve the problem is to fix the user-land app so one would be able to deal with both old and new DT-nodes name. Alternatively you can just replace the dts with older one, where the name still have the "dwc3"-prefix. -Sergey > This will probably be ignored again, but it would be nice if we could > have a release where DTS changes don't break userland for one of my > boards. As it feels like its been awhile. > > thanks > -john
