Hi Hao If I just boot a device to the EFI shell and then connect a USB, edk2 will constantly try to access the device, fail and reset the port. It won't stop doing this, and the USB drive can't be accessed. I tested 13 USB drives; 8 saw this problem, and 5 worked correctly. It doesn't matter which SOC, or if the port is USB 2.0 or 3.0. " Reset the device on error" - this will only attempt enumeration if there isn't an error. "Avoid continuing on error path" - The reset can happen before PortState is zero'd, so running this at the start of the function ensures it will Hopefully, that makes sense! Thanks Sean On Wed, 21 Sept 2022 at 09:24, Wu, Hao A wrote: > Sorry, could you help to explain more on the endless loop? Like what > causes the loop and why the proposed change can resolve the issue. > > I am not experienced enough in the USB domain to quickly figure out the > whole picture with only log being provided. > > > > Best Regards, > > Hao Wu > > > > *From:* Sean Rhodes > *Sent:* Wednesday, September 21, 2022 4:01 PM > *To:* Wu, Hao A > *Cc:* devel@edk2.groups.io; Ni, Ray > *Subject:* Re: [edk2-devel] [PATCH 1/2] MdeModulePkg/UsbBusDxe: Avoid > continuing on error path > > > > Hi Hao > > > > I've attached a debug log for the problem I'm trying to solve (these two > patches solve it). > > > > The reset happens before PortState changes, so it's an endless loop. > > > > Thanks > > > > Sean > > > > On Wed, 21 Sept 2022 at 06:31, Wu, Hao A wrote: > > Sorry, could you help to share more information on what issue is met for > this proposed patch? > > It seems to me that the change made below is to handle the case where: > > Status = HubApi->GetPortStatus (HubIf, Port, &PortState); > > if (EFI_ERROR (Status)) { > DEBUG ((DEBUG_ERROR, "UsbEnumeratePort: failed to get state of port > %d\n", Port)); > return Status; > } > > GetPortStatus() returns EFI_ SUCCESS, but does not update the output > parameter 'PortState'. > Could you help to check what causes 'PortState' not being updated after a > success return from GetPortStatus()? Thanks in advance. > > Also, one inline comment below: > > > > -----Original Message----- > > From: devel@edk2.groups.io On Behalf Of Sean > > Rhodes > > Sent: Tuesday, September 20, 2022 9:14 PM > > To: devel@edk2.groups.io > > Cc: Rhodes, Sean ; Wu, Hao A > > ; Ni, Ray > > Subject: [edk2-devel] [PATCH 1/2] MdeModulePkg/UsbBusDxe: Avoid > > continuing on error path > > > > Zero out the PortState in case GetPortStatus didn't set it, to avoid > > continuing with EFI_DEVICE_ERROR. > > > > Cc: Hao A Wu > > Cc: Ray Ni > > Signed-off-by: Sean Rhodes > > --- > > MdeModulePkg/Bus/Usb/UsbBusDxe/UsbEnumer.c | 5 +++++ > > 1 file changed, 5 insertions(+) > > > > diff --git a/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbEnumer.c > > b/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbEnumer.c > > index aed34596f4..7fc567898a 100644 > > --- a/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbEnumer.c > > +++ b/MdeModulePkg/Bus/Usb/UsbBusDxe/UsbEnumer.c > > @@ -900,6 +900,11 @@ UsbEnumeratePort ( > > Child = NULL; > > > > HubApi = HubIf->HubApi; > > > > > > > > + // Zero out PortState in case GetPortStatus does not set it and we > > > > + // continue on the EFI_DEVICE_ERROR path > > > > + PortState.PortStatus = 0; > > > > + PortState.PortChangeStatus = 0; > > > Could you help to use: > > ZeroMem (&PortState, sizeof (EFI_USB_PORT_STATUS)); > > here to align with other places in this driver? > > > Best Regards, > Hao Wu > > > > > > + > > > > // > > > > // Host learns of the new device by polling the hub for port changes. > > > > // > > > > -- > > 2.34.1 > > > > > > > > -=-=-=-=-=-= > > Groups.io Links: You receive all messages sent to this group. > > View/Reply Online (#93989): https://edk2.groups.io/g/devel/message/93989 > > Mute This Topic: https://groups.io/mt/93802896/1768737 > > Group Owner: devel+owner@edk2.groups.io > > Unsubscribe: https://edk2.groups.io/g/devel/unsub [hao.a.wu@intel.com] > > -=-=-=-=-=-= > > > >