From patchwork Tue May 10 09:16:29 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kishon Vijay Abraham I X-Patchwork-Id: 571492 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 195EAC433FE for ; Tue, 10 May 2022 09:16:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238516AbiEJJUr (ORCPT ); Tue, 10 May 2022 05:20:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58662 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232785AbiEJJUq (ORCPT ); Tue, 10 May 2022 05:20:46 -0400 Received: from fllv0016.ext.ti.com (fllv0016.ext.ti.com [198.47.19.142]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 41233209B49; Tue, 10 May 2022 02:16:49 -0700 (PDT) Received: from fllv0035.itg.ti.com ([10.64.41.0]) by fllv0016.ext.ti.com (8.15.2/8.15.2) with ESMTP id 24A9Gd90090433; Tue, 10 May 2022 04:16:39 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1652174199; bh=W3xsAi9812FfVecW+UpGf7VrYIgXss1DjC9tejfjZq8=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=Uymbl8cwUL5ylLy22quAImAkuv30BWq9Vsim7uOFMOP4LqLhYIiFyR4RTlF/BIrUA JsWo1WobzToc3F1zhrb7hPG4dO+/LqKd5ismqw41PkNcnV4kreb4xoNVtAZHDzS2pg OqUtse2ApTNWLIhFd++R1fdALfCGkddiTqisXe5U= Received: from DFLE105.ent.ti.com (dfle105.ent.ti.com [10.64.6.26]) by fllv0035.itg.ti.com (8.15.2/8.15.2) with ESMTPS id 24A9GdQb130963 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 10 May 2022 04:16:39 -0500 Received: from DFLE114.ent.ti.com (10.64.6.35) by DFLE105.ent.ti.com (10.64.6.26) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.14; Tue, 10 May 2022 04:16:39 -0500 Received: from fllv0040.itg.ti.com (10.64.41.20) by DFLE114.ent.ti.com (10.64.6.35) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2308.14 via Frontend Transport; Tue, 10 May 2022 04:16:39 -0500 Received: from a0393678ub.dal.design.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by fllv0040.itg.ti.com (8.15.2/8.15.2) with ESMTP id 24A9GYeJ127131; Tue, 10 May 2022 04:16:37 -0500 From: Kishon Vijay Abraham I To: Greg Kroah-Hartman , Mathias Nyman , Alan Stern CC: Kishon Vijay Abraham I , , , Subject: [RESEND PATCH v2 1/2] usb: core: hcd: Add support for deferring roothub registration Date: Tue, 10 May 2022 14:46:29 +0530 Message-ID: <20220510091630.16564-2-kishon@ti.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220510091630.16564-1-kishon@ti.com> References: <20220510091630.16564-1-kishon@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org It has been observed with certain PCIe USB cards (like Inateck connected to AM64 EVM or J7200 EVM) that as soon as the primary roothub is registered, port status change is handled even before xHC is running leading to cold plug USB devices not detected. For such cases, registering both the root hubs along with the second HCD is required. Add support for deferring roothub registration in usb_add_hcd(), so that both primary and secondary roothubs are registered along with the second HCD. This patch has been added and reverted earier as it triggered a race in usb device enumeration. That race is now fixed in 5.16-rc3, and in stable back to 5.4 commit 6cca13de26ee ("usb: hub: Fix locking issues with address0_mutex") commit 6ae6dc22d2d1 ("usb: hub: Fix usb enumeration issue due to address0 race") CC: stable@vger.kernel.org # 5.4+ Suggested-by: Mathias Nyman Tested-by: Chris Chiu Acked-by: Alan Stern Signed-off-by: Kishon Vijay Abraham I --- drivers/usb/core/hcd.c | 29 +++++++++++++++++++++++------ include/linux/usb/hcd.h | 2 ++ 2 files changed, 25 insertions(+), 6 deletions(-) diff --git a/drivers/usb/core/hcd.c b/drivers/usb/core/hcd.c index d9712c2602af..06eea8848ccc 100644 --- a/drivers/usb/core/hcd.c +++ b/drivers/usb/core/hcd.c @@ -2816,6 +2816,7 @@ int usb_add_hcd(struct usb_hcd *hcd, { int retval; struct usb_device *rhdev; + struct usb_hcd *shared_hcd; if (!hcd->skip_phy_initialization && usb_hcd_is_primary_hcd(hcd)) { hcd->phy_roothub = usb_phy_roothub_alloc(hcd->self.sysdev); @@ -2976,13 +2977,26 @@ int usb_add_hcd(struct usb_hcd *hcd, goto err_hcd_driver_start; } + /* starting here, usbcore will pay attention to the shared HCD roothub */ + shared_hcd = hcd->shared_hcd; + if (!usb_hcd_is_primary_hcd(hcd) && shared_hcd && HCD_DEFER_RH_REGISTER(shared_hcd)) { + retval = register_root_hub(shared_hcd); + if (retval != 0) + goto err_register_root_hub; + + if (shared_hcd->uses_new_polling && HCD_POLL_RH(shared_hcd)) + usb_hcd_poll_rh_status(shared_hcd); + } + /* starting here, usbcore will pay attention to this root hub */ - retval = register_root_hub(hcd); - if (retval != 0) - goto err_register_root_hub; + if (!HCD_DEFER_RH_REGISTER(hcd)) { + retval = register_root_hub(hcd); + if (retval != 0) + goto err_register_root_hub; - if (hcd->uses_new_polling && HCD_POLL_RH(hcd)) - usb_hcd_poll_rh_status(hcd); + if (hcd->uses_new_polling && HCD_POLL_RH(hcd)) + usb_hcd_poll_rh_status(hcd); + } return retval; @@ -3020,6 +3034,7 @@ EXPORT_SYMBOL_GPL(usb_add_hcd); void usb_remove_hcd(struct usb_hcd *hcd) { struct usb_device *rhdev = hcd->self.root_hub; + bool rh_registered; dev_info(hcd->self.controller, "remove, state %x\n", hcd->state); @@ -3030,6 +3045,7 @@ void usb_remove_hcd(struct usb_hcd *hcd) dev_dbg(hcd->self.controller, "roothub graceful disconnect\n"); spin_lock_irq (&hcd_root_hub_lock); + rh_registered = hcd->rh_registered; hcd->rh_registered = 0; spin_unlock_irq (&hcd_root_hub_lock); @@ -3039,7 +3055,8 @@ void usb_remove_hcd(struct usb_hcd *hcd) cancel_work_sync(&hcd->died_work); mutex_lock(&usb_bus_idr_lock); - usb_disconnect(&rhdev); /* Sets rhdev to NULL */ + if (rh_registered) + usb_disconnect(&rhdev); /* Sets rhdev to NULL */ mutex_unlock(&usb_bus_idr_lock); /* diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h index 548a028f2dab..2c1fc9212cf2 100644 --- a/include/linux/usb/hcd.h +++ b/include/linux/usb/hcd.h @@ -124,6 +124,7 @@ struct usb_hcd { #define HCD_FLAG_RH_RUNNING 5 /* root hub is running? */ #define HCD_FLAG_DEAD 6 /* controller has died? */ #define HCD_FLAG_INTF_AUTHORIZED 7 /* authorize interfaces? */ +#define HCD_FLAG_DEFER_RH_REGISTER 8 /* Defer roothub registration */ /* The flags can be tested using these macros; they are likely to * be slightly faster than test_bit(). @@ -134,6 +135,7 @@ struct usb_hcd { #define HCD_WAKEUP_PENDING(hcd) ((hcd)->flags & (1U << HCD_FLAG_WAKEUP_PENDING)) #define HCD_RH_RUNNING(hcd) ((hcd)->flags & (1U << HCD_FLAG_RH_RUNNING)) #define HCD_DEAD(hcd) ((hcd)->flags & (1U << HCD_FLAG_DEAD)) +#define HCD_DEFER_RH_REGISTER(hcd) ((hcd)->flags & (1U << HCD_FLAG_DEFER_RH_REGISTER)) /* * Specifies if interfaces are authorized by default