Re: [PATCH 2/2] MdeModulePkg/Usb/Keyboard.c: don't request protocol before setting

Patrick Rudolph

Until now no regressions have been observed.
I'll provide a full test description using a wide variety of platforms soon.

Kind Regards,
Patrick Rudolph

On Thu, Jan 28, 2021 at 3:14 AM Wu, Hao A <> wrote:

-----Original Message-----
From: Patrick Rudolph <>
Sent: Wednesday, January 20, 2021 11:59 PM
Cc: Wang, Jian J <>; Wu, Hao A <>;
Ni, Ray <>
Subject: [PATCH 2/2] MdeModulePkg/Usb/Keyboard.c: don't request
protocol before setting

From: Matt DeVillier <>

No need to check the interface protocol then conditionally setting, just set it
to BOOT_PROTOCOL and check for error.

This is what Linux does for HID devices as some don't follow the USB spec.
One example is the Aspeed BMC HID keyboard device, which adds a massive
boot delay without this patch as it doesn't respond to 'GetProtocolRequest'.

I am okay with the code change.

But since the current logic is here for a long time, I am not sure whether
other USB keyboard device will have functional/performance impact for this

Besides the above mentioned Aspeed BMC HID keyboard device (which has a
performance issue for the Get_Protocol request that the patch is going to
drop), could you at least try one USB keyboard device that works fine with
the origin code logic to see if there is any side effect for this patch?

Thanks in advance.

Best Regards,
Hao Wu

Signed-off-by: Matt DeVillier <>
Signed-off-by: Patrick Rudolph <>
MdeModulePkg/Bus/Usb/UsbKbDxe/KeyBoard.c | 28 ++++++++++++-------
1 file changed, 17 insertions(+), 11 deletions(-)

diff --git a/MdeModulePkg/Bus/Usb/UsbKbDxe/KeyBoard.c
index 77e20b203f..5914174b4d 100644
--- a/MdeModulePkg/Bus/Usb/UsbKbDxe/KeyBoard.c
+++ b/MdeModulePkg/Bus/Usb/UsbKbDxe/KeyBoard.c
@@ -801,7 +801,6 @@ InitUSBKeyboard (
IN OUT USB_KB_DEV *UsbKeyboardDevice ) {- UINT8 Protocol;
-814,21 +813,28 @@ InitUSBKeyboard (
InitQueue (&UsbKeyboardDevice->EfiKeyQueue, sizeof (EFI_KEY_DATA));
InitQueue (&UsbKeyboardDevice->EfiKeyQueueForNotify, sizeof
(EFI_KEY_DATA)); - UsbGetProtocolRequest (- UsbKeyboardDevice-
UsbIo,- UsbKeyboardDevice->InterfaceDescriptor.InterfaceNumber,-
&Protocol- ); // // Set boot protocol for the USB Keyboard. // This driver
only supports boot protocol. //- if (Protocol != BOOT_PROTOCOL) {-
UsbSetProtocolRequest (- UsbKeyboardDevice->UsbIo,-
BOOT_PROTOCOL+ Status = UsbSetProtocolRequest (+
UsbKeyboardDevice->UsbIo,+ UsbKeyboardDevice-
InterfaceDescriptor.InterfaceNumber,+ BOOT_PROTOCOL+ );+
if (EFI_ERROR (Status)) {+ //+ // If protocol could not be set here, it
means+ // the keyboard interface has some errors and could+ // not be
EFI_P_EC_INTERFACE_ERROR),+ UsbKeyboardDevice->DevicePath );++
return EFI_DEVICE_ERROR; } UsbKeyboardDevice->CtrlOn = FALSE;--

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