From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751566AbdAXIce (ORCPT ); Tue, 24 Jan 2017 03:32:34 -0500 Received: from mail-yw0-f193.google.com ([209.85.161.193]:34104 "EHLO mail-yw0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751439AbdAXIca (ORCPT ); Tue, 24 Jan 2017 03:32:30 -0500 MIME-Version: 1.0 In-Reply-To: References: <1484937994-8076-1-git-send-email-lukas@oxygene.sk> <20170121090834.GC27048@kroah.com> <1485243123.7465.26.camel@suse.com> From: =?UTF-8?B?THVrw6HFoSBMYWxpbnNrw70=?= Date: Tue, 24 Jan 2017 09:31:09 +0100 X-Google-Sender-Auth: 9OdyUr2HODded3nDXtuCR8Yb0bk Message-ID: Subject: Re: [PATCH] USB: Add quirk for WORLDE easykey.25 MIDI keyboard To: Oliver Neukum Cc: Greg Kroah-Hartman , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by mail.home.local id v0O8Wk9g009408 On Tue, Jan 24, 2017 at 8:37 AM, Lukáš Lalinský wrote: > On Tue, Jan 24, 2017 at 8:32 AM, Oliver Neukum wrote: >> Am Montag, den 23.01.2017, 19:36 +0100 schrieb Lukáš Lalinský: >>> I have uploaded both captures here - >>> https://gist.github.com/lalinsky/83148a827d5cd43e79e377d8e1b5ed0d >> >> Indeed it is does not set a configuration. Either the capture >> is incomplete or device and host violate the standard. A device >> may be left unconfigured. > > Is this may or may not? I'm not familiar with USB, so I assumed if > there is only one configuration and there is always one active, it > does not need to be set explicitly because the correct one is already > active. > >> We need to read the descriptors even if we >> see only one configuration to get the power budgeting right. > > Aren't those in the CONFIGURATION descriptors? Reading the STRING > descriptor is probably only useful if you need to print the > configuration details somewhere. I re-ran the capture on a Windows 7 host. The previous capture was missing data, probably due to interactions of the Linux host and Windows VM. https://gist.github.com/lalinsky/2ec7d74b049b448b1f7032d8861ca4a2 It does set the configuration, but does not request the string descriptor. Lukas