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 X-Spam-Level: X-Spam-Status: No, score=-18.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A3027C433E0 for ; Tue, 26 Jan 2021 14:17:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F0C222B51 for ; Tue, 26 Jan 2021 14:17:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392134AbhAZOQu (ORCPT ); Tue, 26 Jan 2021 09:16:50 -0500 Received: from mail.kernel.org ([198.145.29.99]:53266 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392667AbhAZOQi (ORCPT ); Tue, 26 Jan 2021 09:16:38 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 12783206CA; Tue, 26 Jan 2021 14:15:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1611670557; bh=ta2LJeQ35NJjiWDOdPasolz3iOXygMQW0EWIxBnJ4uA=; h=Subject:To:From:Date:From; b=idfBLJStUAu54DM2r9OegEQ6du47aXSrLje5Dn4ENMxL2cXfoHJRqXdTHNBBhbfJk WD2T3BgdeDpPe6I08VBldDI7mX0mtxqO0NfM+CEr0ms0Yunyug4Kq78JUgmPgPCLlN fCIPJvt0qjzRMFsm/2UVE6L2HJxAewJvMkpBTDV8= Subject: patch "USB: usblp: don't call usb_set_interface if there's a single alt" added to usb-linus To: kernel@jeremyfiggins.com, gregkh@linuxfoundation.org, stable@vger.kernel.org, zaitcev@redhat.com From: Date: Tue, 26 Jan 2021 15:15:55 +0100 Message-ID: <1611670555227110@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org This is a note to let you know that I've just added the patch titled USB: usblp: don't call usb_set_interface if there's a single alt to my usb git tree which can be found at git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git in the usb-linus branch. The patch will show up in the next release of the linux-next tree (usually sometime within the next 24 hours during the week.) The patch will hopefully also be merged in Linus's tree for the next -rc kernel release. If you have any questions about this process, please let me know. >From d8c6edfa3f4ee0d45d7ce5ef18d1245b78774b9d Mon Sep 17 00:00:00 2001 From: Jeremy Figgins Date: Sat, 23 Jan 2021 18:21:36 -0600 Subject: USB: usblp: don't call usb_set_interface if there's a single alt Some devices, such as the Winbond Electronics Corp. Virtual Com Port (Vendor=0416, ProdId=5011), lockup when usb_set_interface() or usb_clear_halt() are called. This device has only a single altsetting, so it should not be necessary to call usb_set_interface(). Acked-by: Pete Zaitcev Signed-off-by: Jeremy Figgins Link: https://lore.kernel.org/r/YAy9kJhM/rG8EQXC@watson Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/usblp.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-) diff --git a/drivers/usb/class/usblp.c b/drivers/usb/class/usblp.c index 134dc2005ce9..c9f6e9758288 100644 --- a/drivers/usb/class/usblp.c +++ b/drivers/usb/class/usblp.c @@ -1329,14 +1329,17 @@ static int usblp_set_protocol(struct usblp *usblp, int protocol) if (protocol < USBLP_FIRST_PROTOCOL || protocol > USBLP_LAST_PROTOCOL) return -EINVAL; - alts = usblp->protocol[protocol].alt_setting; - if (alts < 0) - return -EINVAL; - r = usb_set_interface(usblp->dev, usblp->ifnum, alts); - if (r < 0) { - printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n", - alts, usblp->ifnum); - return r; + /* Don't unnecessarily set the interface if there's a single alt. */ + if (usblp->intf->num_altsetting > 1) { + alts = usblp->protocol[protocol].alt_setting; + if (alts < 0) + return -EINVAL; + r = usb_set_interface(usblp->dev, usblp->ifnum, alts); + if (r < 0) { + printk(KERN_ERR "usblp: can't set desired altsetting %d on interface %d\n", + alts, usblp->ifnum); + return r; + } } usblp->bidir = (usblp->protocol[protocol].epread != NULL); -- 2.30.0