On Thu, Jan 21, 2021 at 02:22:43PM +0800, Kai-Heng Feng wrote: > On Tue, Jan 19, 2021 at 6:34 PM Greg Kroah-Hartman > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > On Tue, Jan 19, 2021 at 11:41:59AM +0200, Andy Shevchenko wrote: > > > On Tue, Jan 19, 2021 at 04:41:48PM +0800, Kai-Heng Feng wrote: > > > > On Tue, Jan 19, 2021 at 4:27 PM Greg Kroah-Hartman > > > > <gregkh@xxxxxxxxxxxxxxxxxxx> wrote: > > > > > On Tue, Jan 19, 2021 at 04:15:13PM +0800, Kai-Heng Feng wrote: > > > > > > ... > > > > > > > > Who will use OF_MODALIAS and where have you documented it? > > > > > > > > After this lands in mainline, I'll modify the pull request for systemd > > > > to add a new rule for OF_MODALIAS. > > > > I'll modify the comment on the function to document the change. > > > > > > I'm wondering why to have two fixes in two places instead of fixing udev to > > > understand multiple MODALIAS= events? > > > > It's not a matter of multiple events, it's a single event with a > > key/value pair with duplicate keys and different values. > > > > What is this event with different values supposed to be doing in > > userspace? Do you want multiple invocations of `modprobe` or something > > else? > > > > Usually a "device" only has a single "signature" that modprobe uses to > > look up the correct module for. Modules can support any number of > > device signatures, but traditionally it is odd to think that a device > > itself can be supported by multiple modules, which is what you are > > saying is happening here. > > > > So what should userspace do with this, and why does a device need to > > have multiple module alias signatures? > > >From the original use case [1], I think the "compatible" modalias > should be enough. > Andy and Mika, what do you think? Can we remove the ACPI modalias for this case? Yes, I think that should work. After all we want the match to happen through the DT compatible string if the property is present, not through ACPI IDs.
