On Mon, Dec 19, 2022 at 10:45:43PM +0100, Ladislav Michl wrote: > On Mon, Dec 19, 2022 at 07:31:02PM +0100, Ladislav Michl wrote: > > On Mon, Dec 19, 2022 at 02:25:46PM +0200, Mathias Nyman wrote: > > > Looks like controller didn't complete the stop endpoint command. > > > > > > Event for last completed command (before cycle bit change "c" -> "C") was: > > > 0x00000000028f55a0: TRB 00000000035e81a0 status 'Success' len 0 slot 1 ep 0 type 'Command Completion Event' flags e:c, > > > > > > This was for command at 35e81a0, which in the command ring was: > > > 0x00000000035e81a0: Reset Endpoint Command: ctx 0000000000000000 slot 1 ep 3 flags T:c > > > > > > The stop endpoint command was the next command queued, at 35e81b0: > > > 0x00000000035e81b0: Stop Ring Command: slot 1 sp 0 ep 3 flags c > > > > > > There were a lot of URBs queued for this device, and they are cancelled one by one after disconnect. > > > > > > Was this the only device connected? If so does connecting another usb device to another root port help? > > > Just to test if the host for some reason partially stops a while after last device disconnect? > > > > Device is connected directly into SoC. Once connected into HUB, host doesn't die > > (as noted in other email, sorry for not replying to my own message, so it got lost) > > It seems as intentional (power management?) optimization. If another device is > > plugged in before 5 sec timeout expires, host completes stop endpoint command. > > > > Unfortunately I cannot find anything describing this behavior in > > documentation, so I'll ask manufacturer support. > > As support is usually slow I asked search engine first and this sounds > familiar: > "Synopsis Designware USB3 IP earlier than v3.00a which is configured in silicon > with DWC_USB3_SUSPEND_ON_DISCONNECT_EN=1, would need a specific quirk to prevent > xhci host controller from dying when device is disconnected." > > usb: dwc3: Add quirk for Synopsis device disconnection errata > https://patchwork.kernel.org/project/linux-omap/patch/1424151697-2084-5-git-send-email-Sneeker.Yeh@xxxxxxxxxxxxxx/ > > Any clue what happened with that? I haven't found any meaningfull traces... Just for completeness, this turned into: 41135de1e7fd ("usb: xhci: add quirk flag for broken PED bits") and it is enabled: cc params 0x0220f065 hci version 0x100 quirks 0x0000000002010010 However I do not see original logic there, clearing PORT_CSC before stopping endpoint. > > Both solutions, do nothing or reset controller once last device is unpluged > > works, but I doubt they are suitable for mainline kernel without further > > investigation. > > > > > Another thing is that the stop endpoint command fails after three soft reset tries, > > > does disabling soft reset help? > > > > No, this does not cause any change. > > > > ladis
