From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mx1.white.stw.pengutronix.de (mx1.white.stw.pengutronix.de [185.203.200.13]) (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 8BCD53B9617; Thu, 27 Aug 2026 08:04:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.203.200.13 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787817867; cv=none; b=t1lh55Hq/R2xGyf8t75GEVsR7pMz/9XlCtTn5sCdoBrzBVb75bGiTLGq7K7CYoXtVMpnv1223ZG7qmEWP4HeZw+5vJetrTann4Wu1ixd8bjz6U5T/at7ulr1ntSF7oh3ZmPX6pP12xEF/1FuJIbLw9r6ttylGH2AGPk85BBzxAI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1787817867; c=relaxed/simple; bh=SNyRT5rxQCCe6lGK+DFiDOerNMLATPQpc/CAw0TIWBU=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=vDpq37WTosnJxhR355OGyDpob1E+d+0+kOJWoBH6coydrT3TxRoU5ezxys2OW2ctlZMjnSdDN08aHo4sRWnhz8wV4Q8aEaBzcc11mJz7Wt1k+ybscBX6bdaqEfwO8vFeOlYJSzYSKaUljjXbvq7wl+KO7/utxwpG7Zv7kww8kb0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de; spf=pass smtp.mailfrom=pengutronix.de; arc=none smtp.client-ip=185.203.200.13 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=pengutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pengutronix.de Received: from drehscheibe.grey.stw.pengutronix.de (drehscheibe.grey.stw.pengutronix.de [IPv6:2a0a:edc0:0:c01:1d::a2]) (Authenticated sender: relay-from-drehscheibe.grey.stw.pengutronix.de) by mx1.white.stw.pengutronix.de (Postfix) with ESMTPSA id 13989202200; Thu, 27 Aug 2026 10:04:12 +0200 (CEST) Received: from ptz.office.stw.pengutronix.de ([2a0a:edc0:0:900:1d::77] helo=ratatoskr.pengutronix.de) by drehscheibe.grey.stw.pengutronix.de with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1wzV5n-003ZJW-32; Thu, 27 Aug 2026 10:04:12 +0200 From: Steffen Trumtrar To: Conor Dooley Cc: Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Andrew Davis , Andrew Lunn , Heiner Kallweit , Russell King , netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/3] dt-bindings: dp83867: add binding for output-impedance In-Reply-To: <20260826-salutary-skype-524c69932dc2@spud> (Conor Dooley's message of "Wed, 26 Aug 2026 17:01:26 +0100") References: <20260826-v7-2-topic-dp83867-v2-0-a97b4cec6e93@pengutronix.de> <20260826-v7-2-topic-dp83867-v2-2-a97b4cec6e93@pengutronix.de> <20260826-salutary-skype-524c69932dc2@spud> User-Agent: mu4e 1.14.3; emacs 30.2 Date: Thu, 27 Aug 2026 10:04:07 +0200 Message-ID: <87ik4wgfbc.fsf@pengutronix.de> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha512; protocol="application/pgp-signature" --=-=-= Content-Type: text/plain; format=flowed On 2026-08-26 at 17:01 +01, Conor Dooley wrote: > On Wed, Aug 26, 2026 at 02:48:40PM +0200, Steffen Trumtrar wrote: > > Currently, the output-impedance can only be set to default, minimum or > > maximum or via a nvmem cell. > > In cases where there is no backend for a nvmem cell, a value can not be > > set. > > > > Add a DT binding, 'ti,output-impedance-ohms', for specifying the > > output-impedance via a fixed value. The existing boolean values for > > minimum and maximum still take precedence over the new value. > > > > Signed-off-by: Steffen Trumtrar > > --- > > Documentation/devicetree/bindings/net/ti,dp83867.yaml | 16 ++++++++++++++++ > > 1 file changed, 16 insertions(+) > > > > diff --git a/Documentation/devicetree/bindings/net/ti,dp83867.yaml b/Documentation/devicetree/bindings/net/ti,dp83867.yaml > > index 7a6fe516bab27..49fafe3ce6f47 100644 > > --- a/Documentation/devicetree/bindings/net/ti,dp83867.yaml > > +++ b/Documentation/devicetree/bindings/net/ti,dp83867.yaml > > @@ -38,6 +38,16 @@ properties: > > items: > > - const: io_impedance_ctrl > > > > + ti,output-impedance-ohms: > > + description: | > > + MAC Interface Impedance control to set the programmable output impedance. > > + Valid range is 0x00 to 0x1f (32 steps). > > + - 0x1f = 35 ohms (minimum impedance) > > + - 0x00 = 70 ohms (maximum impedance) > > + - Step size varies with process. > > + minimum: 0 > > + maximum: 31 > > Your property is named in ohms, but not implemented in ohms. So without the -ohms? > pw-bot: changes-requested > > Can't you just achieve the same result using the existing max property? The max property is a boolean which just says "use 70ohms". > I don't get the use case where you specify a max, but then don't want to > use that max. Just set the max to what you actually want? That's why I added the exclusion in the binding, because having nvmem-cells and/or any of the other output-impedance bindings doesn't make any sense. Best regards, Steffen -- Pengutronix e.K. | Dipl.-Inform. Steffen Trumtrar | Steuerwalder Str. 21 | https://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686| Fax: +49-5121-206917-5555 | --=-=-= Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iJAEARYKADgWIQQkoXgOFUjwSVmWFAoavSByCl5WIgUCao/vdxoccy50cnVtdHJh ckBwZW5ndXRyb25peC5kZQAKCRAavSByCl5WItC/AQD1VMwEkHhE52B58HmnCX+b wCkD46VgGZCu2CgbHn2j2wEA8NSy176kK7DWYdHnOtnWGgxAiFb0WzEbthvpscfI /Ak= =VG6h -----END PGP SIGNATURE----- --=-=-=--