On a Lenovo ThinkPad T430 (2342-CTO) with kernel 4.10.1 (and presumably earlier) the "docked" sysfs file always contains 0 for both the ata_bay and battery_bay dock devices (the only dock devices present). This holds true with either a hard drive or DVD drive in the UltraBay both at boot and after hotplug. I reported the issue on the linux-acpi mailing list[1] and am filing it here for tracking. Let me know if an acpidump or any other information would be helpful to debug. Thanks, Kevin 1. https://marc.info/?l=linux-acpi&m=148952016304094&w=2
yes, acpidump would be helpful.
Created attachment 255583 [details] acpidump for Lenovo ThinkPad T430 (2342-CTO) with BIOS G1ETB2WW (2.72)
Does this patch: https://patchwork.kernel.org/patch/9674333/ make any difference?
Yes! With patch https://patchwork.kernel.org/patch/9674333/ applied to b9b3322f13f3 the "docked" sysfs file for the ata_bay dock correctly shows 1 when either a DVD or HD drive is present and 0 when empty, both on boot and after removal/reinsertion. The "docked" sysfs file for the battery_bay dock device still always shows 0 whether or not the main battery is connected. However, upon further reflection, I think this is the expected behavior, assuming the battery_bay dock device refers to the battery connector in the UltraBay slot and that there is no dock device to represent the main battery. (I do not have a battery for the UltraBay slot to test.) So I think that patch fully fixes the issue. Thanks!
Cool, thanks!