Re: [PATCH] usb: typec: tbt: Correct swapped TBT adapter type values

[Tzung-Bi Shih]

On Tue, Aug 18, 2026 at 06:20:03PM +0200, Sven Peter wrote:
> Table F-10 of the USB Type-C Cable and Connector Specification R2.5 on
> page 412 defines bit 16 of the TBT3 Device Discover Mode VDO as 0 = TBT3
> Adapter and 1 = TBT2 Legacy Adapter. Linux has those two swapped since
> their original introduction in commit ca469c292edc ("usb: typec: Add
> definitions for Thunderbolt 3 Alternate Mode").
> 
> ChromiumOS EC's include/usb_pd_tbt.h has them the correct way around
> and references the USB Type-C ECN "Thunderbolt 3 Compatibility Updates"
> as fixing an error where they were originally swapped which is presumably
> where the wrong order originally came from.
> 
> I've also confirmed the correct mapping with an Apple Thunderbolt 3
> to Thunderbolt 2 adapter which does set bit 16 in that VDO.
> 
> Swap the two values and update all users. Also rename the old defines
> so that no user accidentally ends up with an inverted value.
> No functional change.
> 
> Link: https://usb.org/document-library/usb-type-cr-cable-and-connector-specification-release-25
> Link: https://chromium.googlesource.com/chromiumos/platform/ec/+/db93814b6e73c8545d23714fe0674c10814d901a/include/usb_pd_tbt.h#90
> Signed-off-by: Sven Peter <sven@xxxxxxxxxx>
...
>  drivers/platform/chrome/cros_ec_typec.c | 2 +-

For cros_ec_typec.c,
Acked-by: Tzung-Bi Shih <tzungbi@xxxxxxxxxx>