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=-15.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 8C87FC4338F for ; Mon, 2 Aug 2021 21:33:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6933960F9C for ; Mon, 2 Aug 2021 21:33:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232956AbhHBVeF (ORCPT ); Mon, 2 Aug 2021 17:34:05 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:55873 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233313AbhHBVeE (ORCPT ); Mon, 2 Aug 2021 17:34:04 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1627940035; h=In-Reply-To: Content-Type: MIME-Version: References: Message-ID: Subject: Cc: To: From: Date: Sender; bh=b8IL7+f3j4Is7lBvpG+WcoalH2aNdPrYqZ34d0uvjjU=; b=iz2NrNBkOvb/qoeZyt1AEsPX9V4GL+3oNrFmyVEZKQUXCC2Vd6pVa+AkAqudjg1AwxlEBqkL E6dTEbGgFtAFLbQPTdftv3rCDuPRX4havYGDF9ikFedQpJtUBS11dSfXndeqR7kWfWK2Vxlv Vyyiohdr8lycdnJ6zpT5dHl65Co= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyIxZTE2YSIsICJsaW51eC11c2JAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n07.prod.us-east-1.postgun.com with SMTP id 6108649c17c2b4047d3bf72d (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Mon, 02 Aug 2021 21:33:16 GMT Sender: jackp=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id B2975C433F1; Mon, 2 Aug 2021 21:33:15 +0000 (UTC) Received: from jackp-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: jackp) by smtp.codeaurora.org (Postfix) with ESMTPSA id 1CEC5C433D3; Mon, 2 Aug 2021 21:33:03 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 1CEC5C433D3 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=fail smtp.mailfrom=jackp@codeaurora.org Date: Mon, 2 Aug 2021 14:33:01 -0700 From: Jack Pham To: Wesley Cheng Cc: balbi@kernel.org, gregkh@linuxfoundation.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] usb: dwc3: gadget: Avoid runtime resume if disabling pullup Message-ID: <20210802213301.GG25299@jackp-linux.qualcomm.com> References: <1627691374-15711-1-git-send-email-wcheng@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1627691374-15711-1-git-send-email-wcheng@codeaurora.org> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Hi Wesley, On Fri, Jul 30, 2021 at 05:29:34PM -0700, Wesley Cheng wrote: > If the device is already in the runtime suspended state, any call to > the pullup routine will issue a runtime resume on the DWC3 core > device. If the USB gadget is disabling the pullup, then avoid having > to issue a runtime resume, as DWC3 gadget has already been > halted/stopped. > > This fixes an issue where the following condition occurs: > > usb_gadget_remove_driver() > -->usb_gadget_disconnect() > -->dwc3_gadget_pullup(0) > -->pm_runtime_get_sync() -> ret = 0 > -->pm_runtime_put() [async] > -->usb_gadget_udc_stop() > -->dwc3_gadget_stop() > -->dwc->gadget_driver = NULL > ... > > dwc3_suspend_common() > -->dwc3_gadget_suspend() > -->DWC3 halt/stop routine skipped, driver_data == NULL > > This leads to a situation where the DWC3 gadget is not properly > stopped, as the runtime resume would have re-enabled EP0 and event > interrupts, and since we avoided the DWC3 gadget suspend, these > resources were never disabled. > > Signed-off-by: Wesley Cheng > --- > drivers/usb/dwc3/gadget.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c > index a29a4ca..5d08454 100644 > --- a/drivers/usb/dwc3/gadget.c > +++ b/drivers/usb/dwc3/gadget.c > @@ -2435,6 +2435,17 @@ static int dwc3_gadget_pullup(struct usb_gadget *g, int is_on) > } > > /* > + * Avoid issuing a runtime resume if the device is already in the > + * suspended state during gadget disconnect. DWC3 gadget was already > + * halted/stopped during runtime suspend. > + */ > + if (!is_on) { > + pm_runtime_barrier(dwc->dev); > + if (pm_runtime_suspended(dwc->dev)) > + return 0; > + } > + > + /* > * Check the return value for successful resume, or error. For a > * successful resume, the DWC3 runtime PM resume routine will handle > * the run stop sequence, so avoid duplicate operations here. Should this also go to stable with Fixes: 77adb8bdf422 ("usb: dwc3: gadget: Allow runtime suspend if UDC unbinded") ? Jack