From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bm.lauterbach.com (bm.lauterbach.com [62.154.241.218]) (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 16D183451BB for ; Wed, 25 Feb 2026 12:50:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=62.154.241.218 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772023805; cv=none; b=HCY0QxZjvZpqIwAfEReLoaC6bFgQrSZPJ64schGceQZjzr+I9jo9kxUjjlJLJwf6V6ZXSw/DcUy6PhFYcP5PZPnivMCrCRY/jzTwUf8L0jFqhOze/hqBrg5Y77XtYrw7RXLbIPYpAVkt/5lauygmr8dK5B1PftsIzOrywTeZ5Jw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772023805; c=relaxed/simple; bh=kQHJQ31+MdmA1hhfUleG2SzGoQCyhUgQtY3Qh/+g/+g=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=GVJxdns/HQl5awFd9JvbNfWH6/JKE+RYRh/YybeMXAhgQ5wKRO/FmXRu/WhjbdhqhkUhY3zy9KwgRLBR8l15wgFmxGRJoAOEgfWbJPap7WcLKe5rwp/ZSgK6aKSgGchUVos4soKu54JdH87MuJaY+4ZoELNOnyc0Au/Ev0YJU5g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lauterbach.com; spf=pass smtp.mailfrom=lauterbach.com; arc=none smtp.client-ip=62.154.241.218 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lauterbach.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lauterbach.com Received: from ingpc2.intern.lauterbach.com (unknown [10.2.10.44]) (Authenticated sender: ingo.rohloff@lauterbach.com) by bm.lauterbach.com (Postfix) with ESMTPSA id 7DBEE1E0B5CB1; Wed, 25 Feb 2026 13:49:59 +0100 (CET) Date: Wed, 25 Feb 2026 13:49:59 +0100 From: Ingo Rohloff To: Thinh Nguyen Cc: "gregkh@linuxfoundation.org" , "linux-usb@vger.kernel.org" Subject: Re: [PATCH] usb: dwc3: Support for USB3340x ULPI PHY, via "snps,enable_xcvrdly_quirk" Message-ID: <20260225134959.39e775ff@ingpc2.intern.lauterbach.com> In-Reply-To: <20260225000512.tle2eu4gkd4ut6bf@synopsys.com> References: <20260224141438.39524-1-ingo.rohloff@lauterbach.com> <20260225000512.tle2eu4gkd4ut6bf@synopsys.com> Organization: Lauterbach GmbH X-Mailer: Claws Mail 4.3.1 (GTK 3.24.50; x86_64-unknown-linux-gnu) 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=US-ASCII Content-Transfer-Encoding: 7bit X-Bm-Milter-Handled: 166a2dfb-2e12-4590-8fa5-72e30323519f X-Bm-Transport-Timestamp: 1772023799563 On Wed, 25 Feb 2026 00:05:17 +0000 Thinh Nguyen wrote: > > + /* > > + * Fixes High-speed negotiation issue with USB3340, see: > > + * https://.../80000645A.pdf > > + * "Device Enumeration Failure with Link IP Systems" > > This platform specific info and how it was found should go into the > commit message and not here. > Done. > > + * According to documentation on the Internet, > > We should not just reference the "Internet". If you want to reference > some documentation, please provide the DWC_usb3x document section and > version. > I would love to, but Synopsys was completely unwilling to provide a programming manual to me. Synopsys told me I should contact Xilinx (now AMD) for access to the programming manual; and of course Xilinx refused, because Xilinx has signed an NDA. The "Internet" was the only source, where I found this information. The description I provide is from the forum post I now mention in the commit message. I put the description in the code, because I am afraid, that the forum post vanishes and then this information is lost to the public. I guess, if I were to gain access to the official programming manual, citing it might be a violation of the NDA I likely would have signed, but I am not a lawyer. > > > + * DWC3_GUSB2PHYCFG_XCVRDLY: > > + * Adds a delay between the assertion of the > > + * ULPI Transceiver Select signal (for HS) and > > It can be for both ULPI and UTMI. > Ah of course :-) I now mention both: ULPI/UTMI. > > + dwc->enable_xcvrdly_quirk = device_property_read_bool(dev, > > + "snps,enable_xcvrdly_quirk"); > > Use "-" instead of "_" for property name, and change it to > "snps,enable-usb2-transceiver-delay" > > ... > > + unsigned enable_xcvrdly_quirk:1; > > Document the new field. Rename to enable_usb2_transceiver_delay. Done. Note: I used "-" before to avoid having different strings for the member variable and the property name to make it easier to grep for both at the same time. > Also, how are you passing this quirk? Through devicetree or software > node? I don't see the user of this property. > On the hardware I have got (Xilinx Ultrascale+ ZynqMP) I pass it via devicetree. I now added a 2nd commit, which adds documentation for the devicetree bindings. with best regards Ingo Rohloff ------------------------------------------------------------------------- Dipl.-Inform. Ingo ROHLOFF Senior Staff Embedded Systems Engineering phone +49 8102 9876-142 - ingo.rohloff@lauterbach.com Lauterbach Engineering GmbH & Co. KG Altlaufstrasse 40, 85635 Hoehenkirchen-Siegertsbrunn, GERMANY www.lauterbach.com Registered Office: Hoehenkirchen-Siegertsbrunn, Germany, Local Court: Munich, HRA 87406, VAT ID: DE246770537, Managing Directors: Lothar Lauterbach, Stephan Lauterbach, Dr. Thomas Ullmann -------------------------------------------------------------------------