From patchwork Fri Nov 5 16:00:36 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mathias Nyman X-Patchwork-Id: 12605091 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 mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9607EC433F5 for ; Fri, 5 Nov 2021 15:59:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7D28D61101 for ; Fri, 5 Nov 2021 15:59:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233706AbhKEQCi (ORCPT ); Fri, 5 Nov 2021 12:02:38 -0400 Received: from mga05.intel.com ([192.55.52.43]:15049 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233646AbhKEQCh (ORCPT ); Fri, 5 Nov 2021 12:02:37 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10159"; a="318126913" X-IronPort-AV: E=Sophos;i="5.87,212,1631602800"; d="scan'208";a="318126913" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 Nov 2021 08:59:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.87,212,1631602800"; d="scan'208";a="490372721" Received: from mattu-haswell.fi.intel.com ([10.237.72.199]) by orsmga007.jf.intel.com with ESMTP; 05 Nov 2021 08:59:34 -0700 From: Mathias Nyman To: , Cc: mr.yming81@gmail.com, chunfeng.yun@mediatek.com, matthias.bgg@gmail.com, nishadkamdar@gmail.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, eddie.hung@mediatek.com, Mathias Nyman Subject: [PATCH] xhci: Fix USB 3.1 enumeration issues by increasing roothub power-on-good delay Date: Fri, 5 Nov 2021 18:00:36 +0200 Message-Id: <20211105160036.549516-1-mathias.nyman@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20211105133050.GA1590803@rowland.harvard.edu> References: <20211105133050.GA1590803@rowland.harvard.edu> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Some USB 3.1 enumeration issues were reported after the hub driver removed the minimum 100ms limit for the power-on-good delay. Since commit 90d28fb53d4a ("usb: core: reduce power-on-good delay time of root hub") the hub driver sets the power-on-delay based on the bPwrOn2PwrGood value in the hub descriptor. xhci driver has a 20ms bPwrOn2PwrGood value for both roothubs based on xhci spec section 5.4.8, but it's clearly not enough for the USB 3.1 devices, causing enumeration issues. Tests indicate full 100ms delay is needed. Reported-by: Walt Jr. Brake Signed-off-by: Mathias Nyman --- drivers/usb/host/xhci-hub.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/usb/host/xhci-hub.c b/drivers/usb/host/xhci-hub.c index a3f875eea751..af946c42b6f0 100644 --- a/drivers/usb/host/xhci-hub.c +++ b/drivers/usb/host/xhci-hub.c @@ -257,7 +257,6 @@ static void xhci_common_hub_descriptor(struct xhci_hcd *xhci, { u16 temp; - desc->bPwrOn2PwrGood = 10; /* xhci section 5.4.9 says 20ms max */ desc->bHubContrCurrent = 0; desc->bNbrPorts = ports; @@ -292,6 +291,7 @@ static void xhci_usb2_hub_descriptor(struct usb_hcd *hcd, struct xhci_hcd *xhci, desc->bDescriptorType = USB_DT_HUB; temp = 1 + (ports / 8); desc->bDescLength = USB_DT_HUB_NONVAR_SIZE + 2 * temp; + desc->bPwrOn2PwrGood = 10; /* xhci section 5.4.8 says 20ms */ /* The Device Removable bits are reported on a byte granularity. * If the port doesn't exist within that byte, the bit is set to 0. @@ -344,6 +344,7 @@ static void xhci_usb3_hub_descriptor(struct usb_hcd *hcd, struct xhci_hcd *xhci, xhci_common_hub_descriptor(xhci, desc, ports); desc->bDescriptorType = USB_DT_SS_HUB; desc->bDescLength = USB_DT_SS_HUB_SIZE; + desc->bPwrOn2PwrGood = 50; /* usb 3.1 may fail if less than 100ms */ /* header decode latency should be zero for roothubs, * see section 4.23.5.2.