Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935568AbdCMBbJ (ORCPT ); Sun, 12 Mar 2017 21:31:09 -0400 Received: from netrider.rowland.org ([192.131.102.5]:44643 "HELO netrider.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S933632AbdCMBbF (ORCPT ); Sun, 12 Mar 2017 21:31:05 -0400 Date: Sun, 12 Mar 2017 21:31:03 -0400 (EDT) From: Alan Stern X-X-Sender: stern@netrider.rowland.org To: Dave Mielke cc: Samuel Thibault , , , , , , Subject: Re: [PATCH] usb-core: Add MS_INTR_BINTERVAL USB quirk In-Reply-To: <20170312214247.GB20039@beta.private.mielke.cc> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 781 Lines: 21 On Sun, 12 Mar 2017, Dave Mielke wrote: > [quoted lines by Alan Stern on 2017/03/12 at 17:18 -0400] > > >Interesting. This is a high-speed device that mistakenly uses the > >low/full-speed encoding for an interrupt bInterval value? > > Yes. > > >That's pretty unusual. Most HID devices (which includes the Braille > >devices I have heard of) run at low speed, and a few of them run at > >full speed. I can't remember any running at high speed. > > According to my collection of data, 5 say 1.00, 15 say 1.1, and 21 say 2.0. A device's speed is only partially related to its USB version. A USB-1.1 device can run at low speed or full speed. A USB-2 device can run at low, full, or high speed. And a USB-3 device can run at low, full, high, or Super speed. Alan Stern