On Thu, 05 Mar 2020, Rajat Jain <rajatja@xxxxxxxxxx> wrote: > On Thu, Mar 5, 2020 at 1:41 AM Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> wrote: >> >> On Wed, 04 Mar 2020, Rajat Jain <rajatja@xxxxxxxxxx> wrote: >> 1) See if we can postpone creating and attaching properties to connector >> ->late_register hook. (I didn't have the time to look into it yet, at >> all.) > > Apparently not. The drm core doesn't like to add properties in > late_register() callback. I just tried it and get this warning: I kind of had a feeling this would be the case, thanks for checking. >> 2) Provide a way to populate connector->acpi_device_id and >> connector->acpi_handle on a per-connector basis. At least the device id >> remains constant for the lifetime of the drm_device > > Are you confirming that the connector->acpi_device_id remains constant > for the lifetime of the drm_device, as calculated in > intel_acpi_device_id_update()? Even in the face of external displays > (monitors) being connected and disconnected during the lifetime of the > system? If so, then I think we can have a solution. First I thought so. Alas it does not hold for DP MST, where you can have connectors added and removed dynamically. I think we could ensure they stay the same for all other connectors though. I'm pretty sure this is already the case; they get added/removed after all others. Another thought, from the ACPI perspective, I'm not sure the dynamically added/removed DP MST connectors should even have acpi handles. But again, tying all this together with ACPI stuff is not something I am an expert on. >> (why do we keep >> updating it at every resume?!) but can we be sure ->acpi_handle does >> too? (I don't really know my way around ACPI.) > > I don't understand why this was being updated on every resume in that > case (this existed even before my patchset). I believe we do not need > it. Yes, the ->acpi_handle will not change if the ->acpi_device_id > does not change. I believe the way forward should then be to populate > connector->acpi_device_id and connector->acpi_handle ONE TIME at the > time of connector init (and not update it on every resume). Does this > sound ok? If a DP MST connector gets removed, should the other ACPI display indexes after that shift, or remain the same? I really don't know. BR, Jani. -- Jani Nikula, Intel Open Source Graphics Center _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
