On Mon, Oct 16, 2023 at 03:05:09PM +0000, Wu, Wentong wrote: > > From: Shevchenko, Andriy > > On Mon, Oct 16, 2023 at 08:52:28AM +0300, Wu, Wentong wrote: > > > > On 10/13/23 22:05, Shevchenko, Andriy wrote: > > > > > On Thu, Oct 12, 2023 at 01:14:23PM +0200, Hans de Goede wrote: > > > > <snip> > > > > > > >> Ah ok, I see. So the code: > > > > >> > > > > >> 1. First tries to find the matching child acpi_device for the > > > > >> auxdev by ADR > > > > >> > > > > >> 2. If 1. fails then falls back to HID + UID matching > > > > >> > > > > >> And there are DSDTs which use either: > > > > >> > > > > >> 1. Only use _ADR to identify which child device is which, like the example > > > > >> DSDT snippet from the commit msg. > > > > >> > > > > >> 2. Only use _HID + _UID like the 2 example DSDT snippets from me > > > > >> email > > > > >> > > > > >> But there never is a case where both _ADR and _HID are used at > > > > >> the same time (which would be an ACPI spec violation as Andy said). > > > > >> > > > > >> So AFAICT there is no issue here since _ADR and _HID are never > > > > >> user at the same time and the commit message correctly describes > > > > >> scenario 1. from above, so the commit message is fine too. > > > > >> > > > > >> So I believe that we can continue with this patch series in its > > > > >> current v20 form, which has already been staged for going into > > > > >> -next by Greg. > > > > >> > > > > >> Andy can you confirm that moving ahead with the current version > > > > >> is ok ? > > > > > > > > > > Yes as we have a few weeks to fix corner cases. > > > > > > > > > > What I'm worrying is that opening door for _ADR that seems never > > > > > used is kinda an overkill here (resolving non-existing problem). > > > > > > > > I assume that there actually some DSDTs using the _ADR approach and > > > > that this support is not there just for fun. > > > > > > right, it's not for fun, we use _ADR here is to reduce the maintain > > > effort because currently it defines _HID for every new platform and > > > the drivers have to be updated accordingly, while _ADR doesn't have that > > problem. > > > > But this does not confirm if you have such devices. Moreover, My question > > about _CID per function stays the same. Why firmware is not using it? > > Yes, both _ADR and _CID can stop growing list in the driver. And for _ADR, it also > only require one ID per function. I don't know why BIOS team doesn't select _CID, > but I have suggested use _ADR internally, and , to make things moving forward, > the driver adds support for _ADR here first. > > But you're right, _CID is another solution as well, we will discuss it with firmware > team more. Should I revert this series now until this gets sorted out? thanks, greg k-h
