From patchwork Tue Sep 19 22:43:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wesley Cheng X-Patchwork-Id: 724646 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5194F8462 for ; Tue, 19 Sep 2023 22:43:55 +0000 (UTC) Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2BCC3D8; Tue, 19 Sep 2023 15:43:53 -0700 (PDT) Received: from pps.filterd (m0279863.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 38JMRx5V023125; Tue, 19 Sep 2023 22:43:39 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=from : to : cc : subject : date : message-id : mime-version : content-type; s=qcppdkim1; bh=jHtpJKk7POFiR5q9hlwxDWH7EiQrYYWveCGVt1y0JwI=; b=h4enjKPUawxsIxx5vSe/vWb3aVR95/sWzKmpox1FsS+cdI9J7rHXxCIgq9vYXb8+czGA G756IJlZXb7syrthvY3f00IcD+CqbQre01DJ4hFJu0x1vzT/b3ZjYdCgc4SpTFnDWckd xpqI2TbRYaGzV/fr7ijtUYz89zq+7dA/lyTO/BgnrB+NAUhCGsDPa0Wap/SmitQ1f8O1 LOVeGA6u2h2Ed5nvRoXR9eArWqbDWEcEPGGpzvFFsE1K7MiP24vokPEE0xUXpQawq45X 596YCVwKkQCSbj3RgZoY7Uy07LHBB6iLm93drVTlMhKzWrOCzNvN7rShYna1kPeBZ9E/ SA== Received: from nalasppmta04.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3t7amn9f7q-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 19 Sep 2023 22:43:39 +0000 Received: from nalasex01b.na.qualcomm.com (nalasex01b.na.qualcomm.com [10.47.209.197]) by NALASPPMTA04.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 38JMhcQ4015895 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Tue, 19 Sep 2023 22:43:38 GMT Received: from hu-wcheng-lv.qualcomm.com (10.49.16.6) by nalasex01b.na.qualcomm.com (10.47.209.197) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.36; Tue, 19 Sep 2023 15:43:38 -0700 From: Wesley Cheng To: , CC: , , Wesley Cheng Subject: [PATCH v3] usb: host: xhci: Avoid XHCI resume delay if SSUSB device is not present Date: Tue, 19 Sep 2023 15:43:27 -0700 Message-ID: <20230919224327.29974-1-quic_wcheng@quicinc.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Originating-IP: [10.49.16.6] X-ClientProxiedBy: nalasex01b.na.qualcomm.com (10.47.209.197) To nalasex01b.na.qualcomm.com (10.47.209.197) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-GUID: ERNiHjyMTSzUoduuGDJlF0lL3pl0UxgH X-Proofpoint-ORIG-GUID: ERNiHjyMTSzUoduuGDJlF0lL3pl0UxgH X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.267,Aquarius:18.0.980,Hydra:6.0.601,FMLib:17.11.176.26 definitions=2023-09-19_12,2023-09-19_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 impostorscore=0 phishscore=0 clxscore=1015 bulkscore=0 priorityscore=1501 suspectscore=0 spamscore=0 lowpriorityscore=0 malwarescore=0 mlxlogscore=709 mlxscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2308100000 definitions=main-2309190194 X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW,SPF_HELO_NONE, SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net There is a 120ms delay implemented for allowing the XHCI host controller to detect a U3 wakeup pulse. The intention is to wait for the device to retry the wakeup event if the USB3 PORTSC doesn't reflect the RESUME link status by the time it is checked. As per the USB3 specification: tU3WakeupRetryDelay ("Table 7-12. LTSSM State Transition Timeouts") This would allow the XHCI resume sequence to determine if the root hub needs to be also resumed. However, in case there is no device connected, or if there is only a HSUSB device connected, this delay would still affect the overall resume timing. Since this delay is solely for detecting U3 wake events (USB3 specific) then ignore this delay for the disconnected case and the HSUSB connected only case. Signed-off-by: Wesley Cheng --- Depends-on: https://lore.kernel.org/linux-usb/20230915143108.1532163-3-mathias.nyman@linux.intel.com/ drivers/usb/host/xhci.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c index e1b1b64a0723..1855cab1be56 100644 --- a/drivers/usb/host/xhci.c +++ b/drivers/usb/host/xhci.c @@ -805,6 +805,18 @@ static void xhci_disable_hub_port_wake(struct xhci_hcd *xhci, spin_unlock_irqrestore(&xhci->lock, flags); } +/* + * Utilize suspended_ports and bus_suspended to determine if USB3 device is + * connected. The bus state bits are set by XHCI hub when root hub udev is + * suspended. Used to determine if USB3 remote wakeup considerations need to + * be accounted for during XHCI resume. + */ +static bool xhci_usb3_dev_connected(struct xhci_hcd *xhci) +{ + return !!xhci->usb3_rhub.bus_state.suspended_ports || + !!xhci->usb3_rhub.bus_state.bus_suspended; +} + static bool xhci_pending_portevent(struct xhci_hcd *xhci) { struct xhci_port **ports; @@ -968,6 +980,7 @@ int xhci_resume(struct xhci_hcd *xhci, pm_message_t msg) int retval = 0; bool comp_timer_running = false; bool pending_portevent = false; + bool usb3_connected = false; bool reinit_xhc = false; if (!hcd->state) @@ -1116,9 +1129,14 @@ int xhci_resume(struct xhci_hcd *xhci, pm_message_t msg) * Resume roothubs only if there are pending events. * USB 3 devices resend U3 LFPS wake after a 100ms delay if * the first wake signalling failed, give it that chance. + * Avoid this check if there are no devices connected to + * the SS root hub. (i.e. HS device connected or no device + * connected) */ pending_portevent = xhci_pending_portevent(xhci); - if (!pending_portevent && msg.event == PM_EVENT_AUTO_RESUME) { + usb3_connected = xhci_usb3_dev_connected(xhci); + if (!pending_portevent && usb3_connected && + msg.event == PM_EVENT_AUTO_RESUME) { msleep(120); pending_portevent = xhci_pending_portevent(xhci); }