From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 26E2A24A054; Wed, 20 Aug 2025 20:03:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755720236; cv=none; b=JgDa9WSsQTU0nfuj6tuK/xmUYrnQbdQJEZGnf46biPHI9074YuoK4sgo+5cAvmrYHhD6j1T5Iz4oVydUEwZnjw/ICqJ0gqLWPIQdEpk1qgFoYn1UpgWErl6JQZ4i/MaV1x33oLxGj60IcIcTwSbf00jHF6QNKyAt2U5Y2GRBuyc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755720236; c=relaxed/simple; bh=anNhsvCEDdZAFrVHuAW6Yq14ZRmsgEq59nDp1oTYxZ0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=s7uXyoQZqmrNEIgJt5nolvE62cqG+WmW8+JYgvZLyqqlvJBdj6ZtxyqSYzK//8TW3fbH10MMvMOmXGbzBDaRMEqd3XbP1zR20HTERiounp/IDi6rkuBT9Ry8d8ux8mVMW03Hgb2KJn3IRFa4un3TLHbtYhILBjc7LWLyF2J14s0= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=GeHJaS6B; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="GeHJaS6B" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 07889C4CEE7; Wed, 20 Aug 2025 20:03:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1755720235; bh=anNhsvCEDdZAFrVHuAW6Yq14ZRmsgEq59nDp1oTYxZ0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GeHJaS6B8aM9Udh1FibxBFg3+IsWGhQ5XurO6jabKMivoDhVotrmQPElYvdfiUnRX y50h/H3ETrqUKhsSB7ipAOr8XJDPlcB5VXzl/QAVJESTe4+OUh1yTMQONS0d0lhS4O FfSeEtEh0cI18x9kpZkpuGWBxQwqgvgqj4f16DSkyhzeiUTzzk5Hk8K0j6Rz1f6SMz Bj0gzFyyqGDrFWgKRGtLJ9P1YpqNwB2cyokm+8YF26QOVw0KA9jgP+9jpkgUcRbLHT Nb7lRBcXe+Y42ezBDMzF7S44Le8bE1CoFX5R+jbW+Fi4wRsDWQJ+ey89iYQb0lMT7G seJ+tPSW9SU1Q== Date: Wed, 20 Aug 2025 15:03:54 -0500 From: Rob Herring To: Nuno =?iso-8859-1?Q?S=E1?= Cc: Guenter Roeck , nuno.sa@analog.com, linux-hwmon@vger.kernel.org, linux-gpio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, Lee Jones , Krzysztof Kozlowski , Conor Dooley , Jean Delvare , Jonathan Corbet , Linus Walleij , Bartosz Golaszewski Subject: Re: [PATCH 0/6] mfd: Add support for the LTC4283 Hot Swap Controller Message-ID: <20250820200354.GA602656-robh@kernel.org> References: <20250814-ltc4283-support-v1-0-88b2cef773f2@analog.com> <5713bb5b-3301-46bc-b30a-d2e4c58d1036@roeck-us.net> <2svr42ee7akwxwj5nizwe4a4hqdk4rslv7ivxraqg3jy6m3mxz@lfpn2nx4jdmm> Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <2svr42ee7akwxwj5nizwe4a4hqdk4rslv7ivxraqg3jy6m3mxz@lfpn2nx4jdmm> On Thu, Aug 14, 2025 at 03:15:29PM +0100, Nuno Sá wrote: > On Thu, Aug 14, 2025 at 05:54:26AM -0700, Guenter Roeck wrote: > > On 8/14/25 03:52, Nuno Sá via B4 Relay wrote: > > > The LTC4283 device features programmable current limit with foldback and > > > independently adjustable inrush current to optimize the MOSFET safe > > > operating area (SOA). The SOA timer limits MOSFET temperature rise for > > > reliable protection against overstresses. > > > > > > An I2C interface and onboard ADC allow monitoring of board current, voltage, > > > power, energy, and fault status. > > > > > > It also features 8 pins that can be configured as GPIO devices. But since > > > the main usage for this device is monitoring, the GPIO part is optional > > > while the HWMON is being made as required. > > > > > > Also to note that the device has some similarities with the already > > > supported ltc4282 hwmon driver but it is different enough to be in it's own > > > driver (apart from being added as MFD). The register map is also fairly > > > different. > > > > > > Last time (for the ltc4282) I tried to add the gpio bits directly in the > > > hwmon driver but Guenter did not really liked it and so this time I'm doing > > > it as MFD. > > > > > Nowadays I suggest that people use auxiliary drivers in such situations. > > I see. But do you have any issue with it being MFD? I do... > I'm anyways tempted to the auxiliary device idea. The main usage for > this device is HWMON and I dunno anyone would use it only as a GPIO > controller. With the auxiliary device we would only need one bindings file > and slightly better bindings for the pins functionality. For this reason. The driver structure influencing the binding design is a problem, but I think MFD is more to blame on that. Rob