Am 14.10.19 um 10:06 schrieb Mathias Nyman: > On 13.10.2019 3.33, Bernhard Gebetsberger wrote: >> According to the xhci specification(chapter 4.6.8.1) soft retry >> shouldn't be used if the slot id is higher than 0. Currently some usb >> devices break on some systems because soft retry is being used when >> there is a transaction error, without checking the slot id. >> > That is not correct > > Specs say that soft retry should not be used if we are dealing with a > FS/LS device behind a HS hub, this can be checked from the "TT Hub Slot ID" > field in the slot context, which we do. > > In xhci all devices have a slot id, so this change would prevent > soft retry almost completely. > > Specs 4.6.8.1: > "Soft Retry attempts shall not be performed if the device is behind a > TT in a HS Hub (i.e. TT Hub Slot ID > ‘0’)." > > -Mathias Thanks for the explanation, I have misunderstood that part from the xhci spec. Sorry. - Bernhard
