From mboxrd@z Thu Jan 1 00:00:00 1970 From: Guillaume Gardet Date: Tue, 18 Aug 2015 13:55:42 +0200 Subject: [U-Boot] USB keyboard does not work on DWC2 controller (on Raspberry Pi B) Message-ID: <55D31D3E.1040405@free.fr> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Stephen, I want to add USB keyboard support to raspberry pi but I get the following error when I do 'usb start' with a keyboard plugged-in: unable to get device descriptor (error=-22) Ethernet chip and mass storage devices are found. I found this thread from February: http://lists.denx.de/pipermail/u-boot/2015-February/206593.html which says: ********** This error is because the keyboard driver uses interrupt transfers, and these aren't implemented in DWC2 ********** But in April, you added a patch series including "usb: dwc2: implement interrupt transfers". But there is also a note: ********** With all these commits applied, both my USB keyboards (one LS Lenovo and one FS Dell) work correctly when there is no USB hub between the SoC and the keyboard; We still need split transactions to be implemented for hubs to work. ********** So, I guess this is expected that USB keyboard does not work on DWC2 / RPi B since it uses a USB hub (SMSC LAN9512)? Guillaume