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

["Wu, Hao A" <hao.a.wu@intel.com>]

> -----Original Message-----
> From: Patrick Rudolph <patrick.rudolph@9elements.com>
> Sent: Wednesday, January 20, 2021 11:59 PM
> To: devel@edk2.groups.io
> Cc: Wang, Jian J <jian.j.wang@intel.com>; Wu, Hao A <hao.a.wu@intel.com>;
> Ni, Ray <ray.ni@intel.com>
> Subject: [PATCH 2/2] MdeModulePkg/Usb/Keyboard.c: don't request
> protocol before setting
> 
> From: Matt DeVillier <matt.devillier@gmail.com>
> 
> 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
change.

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 <matt.devillier@gmail.com>
> Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
> ---
>  MdeModulePkg/Bus/Usb/UsbKbDxe/KeyBoard.c | 28 ++++++++++++-------
> -
>  1 file changed, 17 insertions(+), 11 deletions(-)
> 
> diff --git a/MdeModulePkg/Bus/Usb/UsbKbDxe/KeyBoard.c
> b/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;
> EFI_STATUS          Status;    REPORT_STATUS_CODE_WITH_DEVICE_PATH (@@
> -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,-
> UsbKeyboardDevice->InterfaceDescriptor.InterfaceNumber,-
> 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
> initialized+    //+    REPORT_STATUS_CODE_WITH_DEVICE_PATH (+
> EFI_ERROR_CODE | EFI_ERROR_MINOR,+      (EFI_PERIPHERAL_KEYBOARD |
> EFI_P_EC_INTERFACE_ERROR),+      UsbKeyboardDevice->DevicePath       );++
> return EFI_DEVICE_ERROR;   }    UsbKeyboardDevice->CtrlOn     = FALSE;--
> 2.26.2