> So if this just affects two macs, why can't the fix be realized as a > quirk that is only enabled on those two systems? Or are they impossible > to detect clearly via DMI data or something like that? I think we should be able to quirk based off the acpi _CID "apple-uart-blth" or _HID "BCM2E7C". Marcel suggested quirking based of the acpi table here https://lore.kernel.org/linux-bluetooth/1D2217A9-EA73-4D93-8D0B-5BC2718D4788@xxxxxxxxxxxx/ This would catch some unaffected Macs, but they don't support the LE Read Transmit Power command anyway (the affected macs were released after it was added to the Bluetooth spec, while the unaffected Macs were released before it was added to the spec, and thus don't support it). I'm not sure how to go about applying a quirk based off this, there are quirks in drivers/bluetooth/hci_bcm.c (no_early_set_baudrate and drive_rts_on_open), but they don't seem to be based off acpi ids. It might be simpler to make it ignore the Unknown Command error, like in this patch https://lore.kernel.org/linux-bluetooth/CABBYNZLjSfcG_KqTEbL6NOSvHhA5-b1t_S=3FQP4=GwW21kuzg@xxxxxxxxxxxxxx/ however that only applies on bluetooth-next and needed the status it checks for to be -56, not 0x01. -- Thanks, Orlando
