From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay2-d.mail.gandi.net (relay2-d.mail.gandi.net [217.70.183.194]) (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 E96C155E59; Thu, 21 Dec 2023 16:10:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="XVVT+V4W" Received: by mail.gandi.net (Postfix) with ESMTPSA id 565394000E; Thu, 21 Dec 2023 16:10:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1703175002; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gkK4AF7fmwjohH95nu92SeMkvjofU4OWgRfUvJJb7ok=; b=XVVT+V4WzVh0CEE9G8BJkmzJRuMJPSQ0fYIRuhZoeEavFCYf+D5n6Zado9dytxztGLfT/8 huvois90EhKVW2xd3vXCoMdFQ5S+qgQrr/Mii/p065Lwxne1Q86RVhkEsL4swDNJy74sQr yBwIl52k3LlbDMeiitvK8XKNJMj/HU0IHl8rGSVRWI8XnGhnpZYw29azFYWsCAXVFmF2C7 jw0vR8P4X8tzsWNHYs9XRasAPRvSGf9ZBktAryAf3iX6/9FmDNl61Cm9ql7qKn3+dfgaYu 8QbZph68Rk/3hSO4bYbGr2Nrp+FVsie2NdrLIwAKq3evuE7ED1D/d3eGVwqQdg== Date: Thu, 21 Dec 2023 17:10:00 +0100 From: =?UTF-8?B?S8O2cnk=?= Maincent To: Mark Brown Cc: Oleksij Rempel , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Jonathan Corbet , Luis Chamberlain , Russ Weight , Greg Kroah-Hartman , "Rafael J. Wysocki" , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Thomas Petazzoni , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, devicetree@vger.kernel.org, Dent Project , Liam Girdwood Subject: Re: [PATCH net-next v2 8/8] net: pse-pd: Add PD692x0 PSE controller driver Message-ID: <20231221171000.45310167@kmaincent-XPS-13-7390> In-Reply-To: References: <20231201-feature_poe-v2-0-56d8cac607fa@bootlin.com> <20231201-feature_poe-v2-8-56d8cac607fa@bootlin.com> <20231204225956.GG981228@pengutronix.de> <20231205064527.GJ981228@pengutronix.de> <4b96b8c8-7def-46e5-9c85-d9e925fb9251@sirena.org.uk> <20231205140203.GK981228@pengutronix.de> <88ed0c94-d052-4564-be0c-79a0f502eda8@sirena.org.uk> <20231221163610.47038996@kmaincent-XPS-13-7390> Organization: bootlin X-Mailer: Claws Mail 3.17.5 (GTK+ 2.24.32; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-GND-Sasl: kory.maincent@bootlin.com On Thu, 21 Dec 2023 15:43:21 +0000 Mark Brown wrote: > On Thu, Dec 21, 2023 at 04:36:10PM +0100, K=C3=B6ry Maincent wrote: > > Mark Brown wrote: =20 >=20 > > > OK... I mean, if they're not using the regulator framework I'm not s= ure > > > it has much impact - there are plenty of internal regulators in devic= es > > > already so it wouldn't be *too* unusual other than the fact that AFAI= CT > > > this is somewhat split between devices within the subsystem? Neither= of > > > the messages was super clear. =20 >=20 > > PSE Power Interface (which is kind of the RJ45 in PSE world) have simil= ar > > functionalities as regulators. We wondered if registering a regulator f= or > > each PSE PI (RJ45 ports) is a good idea. The point is that the PSE > > controller driver will be its own regulator consumer. > > I can't find any example in Linux with such a case of a driver being a > > provider and a consumer of its own regulator. This idea of a regulator > > biting its own tail seems weird to me. Maybe it is better to implement = the > > PSE functionalities even if they are like the regulator functionalities= . =20 >=20 > Is it at all plausible that a system (perhaps an embedded one) might use > something other than PSE? Do you mean to supply power to a RJ45 port? This can be done with a simple regulator. In that case we use the pse_regul= ator driver which is a regulator consumer. I don't know about other cases. Oleksij do you? Regards, --=20 K=C3=B6ry Maincent, Bootlin Embedded Linux and kernel engineering https://bootlin.com