From patchwork Fri May 28 14:04:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Petazzoni X-Patchwork-Id: 449831 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 DE058C2B9F7 for ; Fri, 28 May 2021 14:04:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B37A1613F4 for ; Fri, 28 May 2021 14:04:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236290AbhE1OGb (ORCPT ); Fri, 28 May 2021 10:06:31 -0400 Received: from relay1-d.mail.gandi.net ([217.70.183.193]:27687 "EHLO relay1-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229740AbhE1OGb (ORCPT ); Fri, 28 May 2021 10:06:31 -0400 Received: (Authenticated sender: thomas.petazzoni@bootlin.com) by relay1-d.mail.gandi.net (Postfix) with ESMTPSA id 3735C240016; Fri, 28 May 2021 14:04:54 +0000 (UTC) From: Thomas Petazzoni To: Bin Liu , Greg Kroah-Hartman , Tony Lindgren Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, alexandre.belloni@bootlin.com, Thomas Petazzoni , stable@vger.kernel.org Subject: [PATCH] usb: musb: fix MUSB_QUIRK_B_DISCONNECT_99 handling Date: Fri, 28 May 2021 16:04:46 +0200 Message-Id: <20210528140446.278076-1-thomas.petazzoni@bootlin.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org In commit 92af4fc6ec33 ("usb: musb: Fix suspend with devices connected for a64"), the logic to support the MUSB_QUIRK_B_DISCONNECT_99 quirk was modified to only conditionally schedule the musb->irq_work delayed work. This commit badly breaks ECM Gadget on AM335X. Indeed, with this commit, one can observe massive packet loss: $ ping 192.168.0.100 ... 15 packets transmitted, 3 received, 80% packet loss, time 14316ms Reverting this commit brings back a properly functioning ECM Gadget. An analysis of the commit seems to indicate that a mistake was made: the previous code was not falling through into the MUSB_QUIRK_B_INVALID_VBUS_91, but now it is, unless the condition is taken. Changing the logic to be as it was before the problematic commit *and* only conditionally scheduling musb->irq_work resolves the regression: $ ping 192.168.0.100 ... 64 packets transmitted, 64 received, 0% packet loss, time 64475ms Fixes: 92af4fc6ec33 ("usb: musb: Fix suspend with devices connected for a64") Signed-off-by: Thomas Petazzoni Cc: stable@vger.kernel.org Tested-by: Alexandre Belloni Acked-by: Tony Lindgren Tested-by: Drew Fustini --- drivers/usb/musb/musb_core.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c index 8f09a387b773..4c8f0112481f 100644 --- a/drivers/usb/musb/musb_core.c +++ b/drivers/usb/musb/musb_core.c @@ -2009,9 +2009,8 @@ static void musb_pm_runtime_check_session(struct musb *musb) schedule_delayed_work(&musb->irq_work, msecs_to_jiffies(1000)); musb->quirk_retries--; - break; } - fallthrough; + break; case MUSB_QUIRK_B_INVALID_VBUS_91: if (musb->quirk_retries && !musb->flush_irq_work) { musb_dbg(musb,