From patchwork Fri Jul 15 13:21:52 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Krishna Kurapati X-Patchwork-Id: 590916 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D7A18CCA47C for ; Fri, 15 Jul 2022 13:22:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234668AbiGONWF (ORCPT ); Fri, 15 Jul 2022 09:22:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57162 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229436AbiGONWE (ORCPT ); Fri, 15 Jul 2022 09:22:04 -0400 Received: from alexa-out-sd-01.qualcomm.com (alexa-out-sd-01.qualcomm.com [199.106.114.38]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AD41377A4B; Fri, 15 Jul 2022 06:22:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; i=@quicinc.com; q=dns/txt; s=qcdkim; t=1657891321; x=1689427321; h=from:to:cc:subject:date:message-id:mime-version; bh=nI2RPm3w4Un0V6ziztJ+VrqsFe9o/d2uY5zky8/U5Lo=; b=DPVSTAJo537+ZlnNrAbcDtsFkGoRkPn4xmQLo8wfy9Mut0FaTzd7bzFT pfB7WAlmb+Dy5KNf8bgK0ZFyfl+BmD4DOQGsPhSv4Fs4+a1x7SYglsuzd /Gg2RvpCSU6MOYk7+EWrK8pCWbLmiQr1lNkNJRtBjahAmuj1Z20E/2Xhc 8=; Received: from unknown (HELO ironmsg03-sd.qualcomm.com) ([10.53.140.143]) by alexa-out-sd-01.qualcomm.com with ESMTP; 15 Jul 2022 06:22:01 -0700 X-QCInternal: smtphost Received: from nasanex01c.na.qualcomm.com ([10.47.97.222]) by ironmsg03-sd.qualcomm.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 15 Jul 2022 06:22:00 -0700 Received: from nalasex01a.na.qualcomm.com (10.47.209.196) by nasanex01c.na.qualcomm.com (10.47.97.222) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.22; Fri, 15 Jul 2022 06:22:00 -0700 Received: from hu-kriskura-hyd.qualcomm.com (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.22; Fri, 15 Jul 2022 06:21:56 -0700 From: Krishna Kurapati To: Andy Gross , Bjorn Andersson , Felipe Balbi , "Greg Kroah-Hartman" , Philipp Zabel CC: , , , Krishna Kurapati Subject: [PATCH v2] usb: dwc3: qcom: Defer dwc3-qcom probe if dwc3 isn't probed properly Date: Fri, 15 Jul 2022 18:51:52 +0530 Message-ID: <1657891312-21748-1-git-send-email-quic_kriskura@quicinc.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01a.na.qualcomm.com (10.47.209.196) Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On SC7180 devices, it is observed that dwc3 probing is deferred because device_links_check_suppliers() finds that '88e3000.phy' isn't ready yet. As a part of its probe call, dwc3-qcom driver checks if dwc3 core is wakeup capable or not. If the dwc3 core is wakeup capable, driver configures dwc-qcom's power domain to be always ON. Also it configures dp/dm interrupts accordingly to support wakeup from system suspend. More info regarding the same can be found at: commit d9be8d5c5b03 ("usb: dwc3: qcom: Keep power domain on to retain controller status") commit 6895ea55c385 ("usb: dwc3: qcom: Configure wakeup interrupts during suspend") In the event, dwc3 probe gets deferred and is processed after dwc3-qcom probe, driver ends up reading the wakeup capability of dwc3 core as false leading to instability in suspend/resume path. To avoid this scenario, ensure dwc3_probe is successful by checking if appropriate driver is assigned to it or not after the of_platform_populate call. If it isn't then defer dwc3-qcom probe as well. Fixes: 649f5c842ba3 ("usb: dwc3: core: Host wake up support from system suspend") Signed-off-by: Krishna Kurapati Reported-by: Matthias Kaehlcke Tested-by: Matthias Kaehlcke Reviewed-by: Matthias Kaehlcke --- v2: Set return value to EPROBE_DEFER to drop reference to dwc3 node drivers/usb/dwc3/dwc3-qcom.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/usb/dwc3/dwc3-qcom.c b/drivers/usb/dwc3/dwc3-qcom.c index 7703655..6676b39 100644 --- a/drivers/usb/dwc3/dwc3-qcom.c +++ b/drivers/usb/dwc3/dwc3-qcom.c @@ -722,6 +722,9 @@ static int dwc3_qcom_of_register_core(struct platform_device *pdev) dev_err(dev, "failed to get dwc3 platform device\n"); } + if (!qcom->dwc3->dev.driver) + ret = -EPROBE_DEFER; + node_put: of_node_put(dwc3_np);