Quoting Dmitry Torokhov (2022-05-12 16:31:08) > On Thu, May 12, 2022 at 01:11:39PM -0700, Stephen Boyd wrote: > > Quoting Stephen Boyd (2022-05-12 11:58:02) > > > Quoting Dmitry Torokhov (2022-05-12 03:22:30) > > > > > > > > Have we solved module loading in the presence of multiple compatibles? > > > > IIRC we only ever try to load module on the first compatible, so you'd > > > > be breaking autoloading cros-ec-keyb on these older kernels. I think the > > > > cure that is being proposed is worse than the disease. > > > > > > > > > > The first compatible is still cros-ec-keyb in the driver though? Or you > > > mean the first compatible in the node? I'm not aware of this problem at > > > all but I can certainly test out a fake node and module and see if it > > > gets autoloaded. > > > > I can't get this test module to fail to load no matter what I do. I > > commented out the second match table entry, and kept it there and > > removed 'vendor,switch-compat' from the DTS. Module still autoloads. > > > > Ah, indeed, if the module contains both compatibles we will load it. It > is broken when we have 2 or more modules and DT lists several > compatibles for a device. > > OK, it looks like you feel very strongly regarding having a dedicated > compatible. In this case please make sure that the compatible's behavior > is properly documented (i.e. google,cros-ec-keyb compatible does not > imply that there are *NO* switches, and users having buttons and > switches in addition to matrix keys can also use google,cros-ec-keyb as > a compatible for their device). We also need to mention that with the > 2nd compatible the device still can report key/button events, it is > simply that there is no matrix component. Should we call the other > compatible google,cros-ec-bs? ;) I think I covered that in v3 of this series[1]. > > We should also abort binding the device if it specifies the new > compatible, but EC does not report any buttons or switches. Sure. I don't have that done in v3 so I can respin the patch series to fail probe if there aren't any switches and the cros-ec-keyb-switches compatible is present. Can you take a quick glance at v3 and let me know if anything else is needed? [1] https://lore.kernel.org/all/20220503042242.3597561-1-swboyd@xxxxxxxxxxxx/
