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=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 autolearn=unavailable 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 4590EC433ED for ; Fri, 16 Apr 2021 02:04:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 09115611AB for ; Fri, 16 Apr 2021 02:04:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237975AbhDPCEJ (ORCPT ); Thu, 15 Apr 2021 22:04:09 -0400 Received: from szxga06-in.huawei.com ([45.249.212.32]:17362 "EHLO szxga06-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235043AbhDPCEE (ORCPT ); Thu, 15 Apr 2021 22:04:04 -0400 Received: from DGGEMS403-HUB.china.huawei.com (unknown [172.30.72.59]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4FLzwT1z70zkkWr; Fri, 16 Apr 2021 10:01:45 +0800 (CST) Received: from [10.67.102.118] (10.67.102.118) by DGGEMS403-HUB.china.huawei.com (10.3.19.203) with Microsoft SMTP Server id 14.3.498.0; Fri, 16 Apr 2021 10:03:23 +0800 Subject: Re: [RFC PATCH] USB:XHCI:skip hub registration To: Alan Stern CC: , , , , , , References: <1618489358-42283-1-git-send-email-liulongfang@huawei.com> <20210415144323.GC1530055@rowland.harvard.edu> From: liulongfang Message-ID: <3dad6f4f-6386-427c-c36c-7d26b9a76fa4@huawei.com> Date: Fri, 16 Apr 2021 10:03:21 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20210415144323.GC1530055@rowland.harvard.edu> Content-Type: text/plain; charset="gbk" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.102.118] X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021/4/15 22:43, Alan Stern wrote: > On Thu, Apr 15, 2021 at 08:22:38PM +0800, Longfang Liu wrote: >> When the number of ports on the USB hub is 0, skip the registration >> operation of the USB hub. >> >> The current Kunpeng930's XHCI hardware controller is defective. The number >> of ports on its USB3.0 bus controller is 0, and the number of ports on >> the USB2.0 bus controller is 1. >> >> In order to solve this problem that the USB3.0 controller does not have >> a port which causes the registration of the hub to fail, this patch passes >> the defect information by adding flags in the quirks of xhci and usb_hcd, >> and finally skips the registration process of the hub directly according >> to the results of these flags when the hub is initialized. >> >> Signed-off-by: Longfang Liu > > The objections that Greg raised are all good ones. > > But even aside from them, this patch doesn't actually do what the > description says. The patch doesn't remove the call to usb_add_hcd > for the USB-3 bus. If you simply skipped that call (and the > corresponding call to usb_remove_hcd) when there are no > ports on the root hub, none of the stuff in this patch would be needed. > > Alan Stern > "[RFC PATCH] USB:XHCI:Adjust the log level of hub" The current method is an improved method of the above patch. This patch just make it skip registering USB-3 root hub if that hub has no ports, after skipping registering, no port will not report error log,the goal of this patch is reached without error log output. Thanks. Longfang. >> --- >> drivers/usb/core/hub.c | 6 ++++++ >> drivers/usb/host/xhci-pci.c | 4 ++++ >> drivers/usb/host/xhci.c | 5 +++++ >> drivers/usb/host/xhci.h | 1 + >> include/linux/usb/hcd.h | 1 + >> 5 files changed, 17 insertions(+) >> >> diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c >> index b1e14be..2d6869d 100644 >> --- a/drivers/usb/core/hub.c >> +++ b/drivers/usb/core/hub.c >> @@ -1769,9 +1769,15 @@ static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id) >> struct usb_host_interface *desc; >> struct usb_device *hdev; >> struct usb_hub *hub; >> + struct usb_hcd *hcd; >> >> desc = intf->cur_altsetting; >> hdev = interface_to_usbdev(intf); >> + hcd = bus_to_hcd(hdev->bus); >> + if (hcd->usb3_no_port) { >> + dev_warn(&intf->dev, "USB hub has no port\n"); >> + return -ENODEV; >> + } >> >> /* >> * Set default autosuspend delay as 0 to speedup bus suspend, >> diff --git a/drivers/usb/host/xhci-pci.c b/drivers/usb/host/xhci-pci.c >> index ef513c2..63b89a4 100644 >> --- a/drivers/usb/host/xhci-pci.c >> +++ b/drivers/usb/host/xhci-pci.c >> @@ -281,6 +281,10 @@ static void xhci_pci_quirks(struct device *dev, struct xhci_hcd *xhci) >> if (xhci->quirks & XHCI_RESET_ON_RESUME) >> xhci_dbg_trace(xhci, trace_xhci_dbg_quirks, >> "QUIRK: Resetting on resume"); >> + >> + if (pdev->vendor == PCI_VENDOR_ID_HUAWEI && >> + pdev->device == 0xa23c) >> + xhci->quirks |= XHCI_USB3_NOPORT; >> } >> >> #ifdef CONFIG_ACPI >> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c >> index bee5dec..e3e3573 100644 >> --- a/drivers/usb/host/xhci.c >> +++ b/drivers/usb/host/xhci.c >> @@ -5184,6 +5184,11 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks) >> /* xHCI private pointer was set in xhci_pci_probe for the second >> * registered roothub. >> */ >> + if (xhci->quirks & XHCI_USB3_NOPORT) { >> + xhci_info(xhci, "xHCI host has no port\n"); >> + hcd->usb3_no_port = 1; >> + } >> + >> return 0; >> } >> >> diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h >> index 2c6c4f8..d3c658f 100644 >> --- a/drivers/usb/host/xhci.h >> +++ b/drivers/usb/host/xhci.h >> @@ -1874,6 +1874,7 @@ struct xhci_hcd { >> #define XHCI_RESET_PLL_ON_DISCONNECT BIT_ULL(34) >> #define XHCI_SNPS_BROKEN_SUSPEND BIT_ULL(35) >> #define XHCI_RENESAS_FW_QUIRK BIT_ULL(36) >> +#define XHCI_USB3_NOPORT BIT_ULL(37) >> >> unsigned int num_active_eps; >> unsigned int limit_active_eps; >> diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h >> index 3dbb42c..7df23a0f 100644 >> --- a/include/linux/usb/hcd.h >> +++ b/include/linux/usb/hcd.h >> @@ -172,6 +172,7 @@ struct usb_hcd { >> unsigned tpl_support:1; /* OTG & EH TPL support */ >> unsigned cant_recv_wakeups:1; >> /* wakeup requests from downstream aren't received */ >> + unsigned usb3_no_port:1; /* xHCI main_hcd has no port */ >> >> unsigned int irq; /* irq allocated */ >> void __iomem *regs; /* device memory/io */ >> -- >> 2.8.1 >> > . >