From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A218CC433EF for ; Fri, 29 Apr 2022 15:46:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378238AbiD2Ptx (ORCPT ); Fri, 29 Apr 2022 11:49:53 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37550 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1378617AbiD2Ptw (ORCPT ); Fri, 29 Apr 2022 11:49:52 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0A39733365 for ; Fri, 29 Apr 2022 08:46:32 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 19B81B833A7 for ; Fri, 29 Apr 2022 15:46:31 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 880F5C385A7; Fri, 29 Apr 2022 15:46:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1651247189; bh=g5k+KEhmTWniGGF1Pr1q2zMLtVoWz7Xz6i5msM4iaCY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=AyHWGFd+3Ba65jJav4PA8n9u0cBgHQE5NaIdL8Sx+HwI/3TkGhQHyzxuvha1x2vMe ZToJ5Nwy5/SVVlB752pX6cMqCgwyrk9k4dotIznS56gT3p5qMby0+bwV/bH+Yml0vz MxrBTSXUtonsDhte0Qd+20HGB597b3cAtDCIr2bs= Date: Fri, 29 Apr 2022 17:46:27 +0200 From: Greg KH To: Jose Ignacio Tornos Martinez Cc: linux-usb@vger.kernel.org, marcel@holtmann.org Subject: Re: [PATCH] Bluetooth: btusb: CSR chip hangs when unbound Message-ID: References: <20220429153138.935435-1-jtornosm@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220429153138.935435-1-jtornosm@redhat.com> Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org On Fri, Apr 29, 2022 at 05:31:38PM +0200, Jose Ignacio Tornos Martinez wrote: > Bluetooth Dongles with CSR chip (i.e. USB Bluetooth V4.0 Dongle by > Trust) hang when they are unbound from 'unbind' sysfs entry and > can not be bound again. > > The reason is CSR chip hangs when usb configuration command with > index 0 (used to unconfigure) is sent during disconnection. > > To avoid this unwanted result, it is necessary not to send this > command for CSR chip when usb device is unbound. > Besides, "skip_unconfigure" sysfs entry has been created for > testing purposes with these or other devices. > > Athough device is not unconfigured, it is better to avoid device > hanging to be able to operate. Even bluetooth can be previously > turned off. > On the other hand, this is not important if usb device is going to > be bound again (normal behavior), i.e. with usbip. > > Signed-off-by: Jose Ignacio Tornos Martinez > --- > drivers/bluetooth/btusb.c | 8 +++++++- > drivers/usb/core/generic.c | 2 +- > drivers/usb/core/sysfs.c | 36 ++++++++++++++++++++++++++++++++++++ > include/linux/usb.h | 2 ++ > 4 files changed, 46 insertions(+), 2 deletions(-) No documentation for this new sysfs attribute you wish to create? That's not going to help us with review :( thanks, greg k-h