Re: No PNP0CA0 device on a Dell Precision 5520 laptop

[Heikki Krogerus <heikki.krogerus@linux.intel.com>]

On Tue, Feb 11, 2020 at 03:14:10PM +0100, Oliver Neukum wrote:
> Am Dienstag, den 11.02.2020, 15:59 +0200 schrieb Heikki Krogerus:
> > cat /sys/bus/acpi/devices/USBC000\:00/status
> 
> Technically -ENODEV. It does not exist, even in a listing.
> But this thing definitely has a type C port. It is connected
> to a docking station which supplies the whole system with power.
> Ethernet also works.

There is still no requirement for the BIOS or the EC firmware to
expose UCSI to the operating system. If the ACPI node is not there,
then there is no UCSI on that system. The USB Type-C connectors
function autonomously in any case on a system that exposes them to the
operating system with UCSI. UCSI is more like an optional status
interface that allows limited control over some specific things like
role swapping.

UCSI is usually supported when the USB Power Delivery (USB PD)
controllers are connected to the Embedded Controller on the system,
but on some of our platforms they are directly connected to the SOC
instead. So on those platforms we can directly communicate with the
USB PD controller from the operating system, which is actually much
better situation compared to UCSI IMO.

Do you have this ACPI node: INT3515 ?

It's for the TI TPS6598x USB PD controllers.

thanks,

-- 
heikki