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=-4.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no 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 58E77C4338F for ; Wed, 11 Aug 2021 15:39:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2E83860F46 for ; Wed, 11 Aug 2021 15:39:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232847AbhHKPjX (ORCPT ); Wed, 11 Aug 2021 11:39:23 -0400 Received: from mail.kernel.org ([198.145.29.99]:41742 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232120AbhHKPjW (ORCPT ); Wed, 11 Aug 2021 11:39:22 -0400 Received: by mail.kernel.org (Postfix) with ESMTPS id CB4FD60F46 for ; Wed, 11 Aug 2021 15:38:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1628696338; bh=Csgp003FOCCmeRzJjvATp4JTaXO2kH0zZuL4lQYi4rQ=; h=From:To:Subject:Date:In-Reply-To:References:From; b=PpyC4Dm57tmI3Cd07leGdAOqy0Blv1Z7cm3ayOfDDicPWfMUsp6RMezQp/gGGQsNp l7JgYGxidd2wlPxIZZO5Whl1CnQU9LNBObR3cF3tZPw4b4yzVMDOH6BBOxnDe9i78+ CBaih/QXjapt30Rs96lwoUEPUTHqWVmoog5Rz0kEH6Nsb9zDGeQzVFpwoh/ySxPZ0+ i7fxbwxlCP93tnIIXf2yhEY7JXooJvYKAyjRG56T0uUpPGj0g8siQcKoHZEE/08PVr 7CMHIZAOAuuVOzxOpuZhaye7B54eIYAmfNSl75+mYWMVCcF+ICrHTYp4vvcGkx2G9K P6kwCrtM9oSzA== From: bugzilla-daemon@bugzilla.kernel.org To: linux-usb@vger.kernel.org Subject: [Bug 214021] The USB devices fail to be detected during boot Date: Wed, 11 Aug 2021 15:38:58 +0000 X-Bugzilla-Reason: None X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: AssignedTo drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Product: Drivers X-Bugzilla-Component: USB X-Bugzilla-Version: 2.5 X-Bugzilla-Keywords: X-Bugzilla-Severity: high X-Bugzilla-Who: stern@rowland.harvard.edu X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P1 X-Bugzilla-Assigned-To: drivers_usb@kernel-bugs.kernel.org X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: https://bugzilla.kernel.org/ Auto-Submitted: auto-generated MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org https://bugzilla.kernel.org/show_bug.cgi?id=3D214021 --- Comment #3 from Alan Stern (stern@rowland.harvard.edu) --- You can try changing the bPwrOn2PwrGood value in the kernel source to see if that will make any difference. The line to change is in drivers/usb/host/xhci-hub.c in the function xhci_common_hub_descriptor(). = It's at the start of the function: desc->bPwrOn2PwrGood =3D 10; /* xhci section 5.4.9 says 20ms m= ax */ The value gets multiplied by two, so if you change it to 50 then the delay = will become 100 ms. However I suspect that the length of this delay is not the cause of the pro= blem you see. The actual error occurs in the usb_alloc_dev() function in drivers/usb/core/usb.c. You can try adding some printk statements in there= to see which of the "return NULL" statements is the one you're getting. --=20 You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.=