From patchwork Sat Jul 31 00:29:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wesley Cheng X-Patchwork-Id: 490047 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,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_GIT 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 26EF5C4338F for ; Sat, 31 Jul 2021 00:29:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 05E3A60FED for ; Sat, 31 Jul 2021 00:29:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234518AbhGaA3s (ORCPT ); Fri, 30 Jul 2021 20:29:48 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:48723 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234211AbhGaA3r (ORCPT ); Fri, 30 Jul 2021 20:29:47 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1627691382; h=Message-Id: Date: Subject: Cc: To: From: Sender; bh=fK+tZMR6pKL2c8jQjVZ5FRLeEtgsQl5vSZl1JOIRzjs=; b=Ri4l0OodhaLVPD4+rfoUgQtsSmdVk4x0Fq7QDQ06JoaJCfKb9v7jTDGSe2R3dmVuYznwzun0 QX0kIKrkWf2guPkBtqJvVcpdDPYQU64sulFEgn2GnyIwVsmcZbDgHkY7kHZn1UK8m1SqXLNZ bNYHMx2wPjxDUWTYJZtz8BWGbco= 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-n02.prod.us-west-2.postgun.com with SMTP id 6104997296a66e66b20cd003 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Sat, 31 Jul 2021 00:29:38 GMT Sender: wcheng=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id CC230C43460; Sat, 31 Jul 2021 00:29:38 +0000 (UTC) Received: from wcheng-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: wcheng) by smtp.codeaurora.org (Postfix) with ESMTPSA id B513FC433D3; Sat, 31 Jul 2021 00:29:37 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org B513FC433D3 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=wcheng@codeaurora.org From: Wesley Cheng To: balbi@kernel.org, gregkh@linuxfoundation.org Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Wesley Cheng Subject: [PATCH] usb: dwc3: gadget: Avoid runtime resume if disabling pullup Date: Fri, 30 Jul 2021 17:29:34 -0700 Message-Id: <1627691374-15711-1-git-send-email-wcheng@codeaurora.org> X-Mailer: git-send-email 2.7.4 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org 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.