From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.15]) (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 908972110; Tue, 30 Dec 2025 07:30:15 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.15 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767079817; cv=none; b=FgzaI3IgrO8kHIwyuMgnBP/AFGtF4jLJSLGI3EGoLw8k7mpMNUmkbwVRp3qijiOhu5ApLld4BUDlgtS5iGgWxnLVbQ3kTeSvx4rnpHMr5eqBzBylP1A8eJ0QiUZw5upbQ7D6xdvCFF3RKtT45UZd/ZrIgeE74zxWtJJBS1Ah7Zs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767079817; c=relaxed/simple; bh=7ygs96puQUaMEOUky0TFPUSPyjLxDnk8XZcEeoq7OYk=; h=Date:From:To:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=jArr+Zi+KEXPSrDwKQ+Fp9zRDLk1IPwUiT4AuSgc/1WnLfugJotr/U5OGjl5z2OksaitdMVQxwAcakKt6XaUlHch+1/gcUXKQGEFoZQwozooGSUBZ0TH3y7IhoAqYcLVL7Mafq6naJY1euKULj4RFvtiQV92Pgc+v1oIL7JrkY8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=pass smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=RN6C2mnX; arc=none smtp.client-ip=192.198.163.15 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="RN6C2mnX" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1767079816; x=1798615816; h=date:from:to:subject:message-id:references:mime-version: in-reply-to; bh=7ygs96puQUaMEOUky0TFPUSPyjLxDnk8XZcEeoq7OYk=; b=RN6C2mnXp6JYr832h7uFS5ckaB/eOHU9KDycwc7+46QoSO6hpK0XldIV ThRnzbb02RFq+FdRt39blZbK3cA/NgK6N/Q3qQHqAoE5Pc6kcgkXpDo7K spKmSwvq0J91iQRbg+zFfRwAXsjgeL0iS5RkHMFL/3QOwGwYpPEW4Ypgm BPtHPlmm22d4EQhxtTu/xXEqhqkzhp1r7QmC3tgBarpg7qucBim6wmvxY 3WcIzBHzn5lbwVJmxocEEqCHoYCfPNe1EUP4QNVN2pHxN1l9ZgyMOPIvU IGbNhAUObDPezL9ndXRRevb55hBcGkqky7mJvQh+7ROePnE5lqsAD5l+B w==; X-CSE-ConnectionGUID: EoM0vrjoSie9tAas8O6IXg== X-CSE-MsgGUID: 4CzgPicuSs2XdXlNZgWh/Q== X-IronPort-AV: E=McAfee;i="6800,10657,11656"; a="68744095" X-IronPort-AV: E=Sophos;i="6.21,188,1763452800"; d="scan'208";a="68744095" Received: from orviesa004.jf.intel.com ([10.64.159.144]) by fmvoesa109.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Dec 2025 23:30:15 -0800 X-CSE-ConnectionGUID: TYEiyWJoSRuFldqCWnWqUg== X-CSE-MsgGUID: 81khnhIqRwimFqTXN/0YxA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,188,1763452800"; d="scan'208";a="205680926" Received: from black.igk.intel.com ([10.91.253.5]) by orviesa004.jf.intel.com with ESMTP; 29 Dec 2025 23:30:13 -0800 Received: by black.igk.intel.com (Postfix, from userid 1001) id 923CD8E; Tue, 30 Dec 2025 08:30:11 +0100 (CET) Date: Tue, 30 Dec 2025 08:30:11 +0100 From: Mika Westerberg To: "Chia-Lin Kao (AceLan)" , Mario Limonciello , Andreas Noever , Mika Westerberg , Yehezkel Bernat , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Sanath.S@amd.com, "Lin, Wayne" Subject: Re: [PATCH] [RFC] thunderbolt: Add delay for Dell U2725QE link width Message-ID: <20251230073011.GD2275908@black.igk.intel.com> References: <20251212123941.GK2275908@black.igk.intel.com> <484ff606-ec10-477c-acfe-d4d781e2873d@amd.com> <20251217125507.GR2275908@black.igk.intel.com> <5d7f2661-f02b-4985-b438-196b48c10237@amd.com> <20251218072125.GU2275908@black.igk.intel.com> <6inne3luvw4ot3wqnsaw3gzhlxtd4756i465oto6so5ox3syxp@kibuv4vhvexx> <20251218102021.GV2275908@black.igk.intel.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Mon, Dec 22, 2025 at 09:33:48AM +0800, Chia-Lin Kao (AceLan) wrote: > On Thu, Dec 18, 2025 at 11:20:21AM +0100, Mika Westerberg wrote: > > On Thu, Dec 18, 2025 at 03:35:05PM +0800, Chia-Lin Kao (AceLan) wrote: > > > > Now since USB 2.x has its own wires in Type-C cable this tells me that > > > > there is some real problem with the connection. Have you tried different > > > > cables already? > > > Here is the log I got with another tbt4 cable. > > > I'm using the kernel with Mario suggests modification. > > > > > > https://people.canonical.com/~acelan/bugs/tbt_call_trace/intel/merged_6.18.0-d358e5254674+.patched2.2_new_cable.out > > > > Here I see (assuming I read it right) that the USB 2.x enumerates only > > after the first unplug: > > > > [ 28.589861] usb 3-2: New USB device found, idVendor=1d5c, idProduct=5801, bcdDevice= 1.01 > > [ 28.589864] usb 3-2: New USB device strings: Mfr=1, Product=2, SerialNumber=0 > > [ 28.589865] usb 3-2: Product: USB2.0 Hub > > [ 28.589866] usb 3-2: Manufacturer: Fresco Logic, Inc. > >From the logs, sometimes this hub is enumerated before the call trace > and then enumerated again after the call trace. > > And I also found there are some suspicious USB disconnections while > plugging in the tbt monitor. > > I tried to avoid the USB disconnection by the following modification, > but still no luck. Okay but I think this is not a SW issue, rather an issue with that particular monitor/cable/connection/PD. It is not just the USB4 link that goes down it's the whole type-C connection therefore something is wrong on the electrical side of things (well at least it seems so). Dell also typically validate that their stuff works in Linux so I would expect to got some report from them if that's not the case (unless you are doing just that ;-)) Have you tried this same monitor with Windows? Do you see the same issue there? I would expect so.