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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 8C441C2D0C9 for ; Thu, 12 Dec 2019 17:15:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 710C4205C9 for ; Thu, 12 Dec 2019 17:15:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730140AbfLLRPx (ORCPT ); Thu, 12 Dec 2019 12:15:53 -0500 Received: from muru.com ([72.249.23.125]:46440 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730022AbfLLRPw (ORCPT ); Thu, 12 Dec 2019 12:15:52 -0500 Received: from atomide.com (localhost [127.0.0.1]) by muru.com (Postfix) with ESMTPS id 59D6D80C0; Thu, 12 Dec 2019 17:16:31 +0000 (UTC) Date: Thu, 12 Dec 2019 09:15:49 -0800 From: Tony Lindgren To: Bin Liu , Greg Kroah-Hartman , linux-usb@vger.kernel.org, linux-omap@vger.kernel.org, Merlijn Wajer , Pavel Machek , Sebastian Reichel Subject: Re: [PATCH] usb: musb: fix idling for suspend after disconnect interrupt Message-ID: <20191212171549.GX35479@atomide.com> References: <20191126034151.38154-1-tony@atomide.com> <20191212160059.GI16429@iaqt7> <20191212160946.GR35479@atomide.com> <20191212170829.GA14499@iaqt7> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191212170829.GA14499@iaqt7> User-Agent: Mutt/1.12.2 (2019-09-21) Sender: linux-usb-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org * Bin Liu [191212 17:09]: > On Thu, Dec 12, 2019 at 08:09:46AM -0800, Tony Lindgren wrote: > > That will wake up musb waiting for further interrupts thinking it's > > connected. But after that there are no more interrupts as the cable > > is disconnected so we need to poll the status again. > > > > If we see SUSPEND before DISCONNECT, then things idle fine. > > Does SUSPEND always comes after DISCONNECT on omap2430, or just > sometimes? I guess the USB connector has some issue - when DP/DM pins > are disconnected, SUSPEND interrupt is generated; when VBUS/GND pins are > disconnected, DISCONNECT interrupt is generated. Because DP/DM pins are > shorter than VBUS/GND, SUSPEND should come before DISCONNECT. No this does not always happen, but happens annoyingly often for me to notice. Your explanation sounds good though, and also sounds that can be affected by the wear on a micro-USB connector. Regards, Tony