On Thu, Feb 3, 2022 at 5:27 AM Alex Elder <elder@xxxxxxxxxx> wrote: > > On 2/2/22 11:06 PM, Jakub Kicinski wrote: > > On Tue, 1 Feb 2022 08:07:23 -0600 Alex Elder wrote: > >> At least three platforms require the "qcom,qmp" property to be > >> specified, so the IPA driver can request register retention across > >> power collapse. Update DTS files accordingly. > >> > >> Signed-off-by: Alex Elder <elder@xxxxxxxxxx> > >> --- > >> > >> Dave, Jakub, please let Bjorn take this through the Qualcomm tree. > > > > I don't know much about DT but the patch defining the property is > > targeting net - will it not cause validation errors? Or Bjorn knows > > to wait for the fixes to propagate? Or it doesn't matter? :) > > It might matter sometimes, but in this case it does not. > > If the DT property is present but never referenced by the > code, it doesn't matter. > > The code in this patch looks up the DT property, and its > behavior is affected by whether the property is there > or not. If it's not there, it's treated as an error > that can be safely ignored. > > In the case this fix is actually needed, we'll need > both the code present and DT property defined. If > the code is there but not the property, it's OK, but > the bug won't be fixed quite yet. If there's only one possible node that qcom,qmp points to, you can just get the node by its compatible (of_find_compatible_node()). Then you don't need a DT update to make things work. Of course, this doesn't work too well if there are 10 possible compatibles without a common fallback compatible. Rob
