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Wed, 08 Jul 2026 02:18:51 -0700 (PDT) Date: Wed, 8 Jul 2026 10:19:56 +0100 From: Nuno =?utf-8?B?U8Oh?= To: Guenter Roeck Cc: Fred Chen , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Jonathan Corbet , Shuah Khan , Jonathan Cameron , Wensheng Wang , Frank Li , Brian Chiang , Cosmo Chou , Dixit Parmar , Eddie James , Antoni Pokusinski , Thorsten Blum , Ashish Yadav , Alexis Czezar Torreno , Syed Arif , ChiShih Tsai , Abdurrahman Hussain , Kim Seer Paller , Colin Huang , Yuxi Wang , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-doc@vger.kernel.org Subject: Re: [PATCH 2/2] hwmon: (pmbus) Add driver for Analog Devices MAX20912 and MAX20916 Message-ID: References: <20260707122701.751878-1-fredchen.openbmc@gmail.com> <20260707122701.751878-3-fredchen.openbmc@gmail.com> 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-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: On Tue, Jul 07, 2026 at 06:52:48AM -0700, Guenter Roeck wrote: > On 7/7/26 05:26, Fred Chen wrote: > > Add support for the Analog Devices MAX20912 and MAX20916 dual-output > > multiphase voltage regulators with PMBus interfaces. > > > > Signed-off-by: Fred Chen > > Please provide evidence that those chips actually exist. > Internet search comes up blank. I'll need confirmation > from someone at Analog. Hi Guenter, Well, in fact I'm in the middle of preparing a series that adds support for: "max20826" "max20855b" "max20908" "max20912" "max20916" All the above parts have the datasheet under NDA. But before we had a one page "datasheet" in analog.com but I guess that is gone! For context I mainly did the base (core) driver for max20826 and then Alexis added the other ones. Not sure how to proceed... I can wait and then work on top of what Fred has but this patch is very minimal when compared with what we have. Like: * No regulator support; * No direct mode. The chip has two ways to access registers (paging and * direct mode). * No way to count how many phases we have or if RAIL_B (func[1]) is being used at all. Some other things more intriguing is that these chips, as far as I'm aware (at least for max20826), always have bit 2 set in ON_OFF_CONFIG so a gpio vout. Also we needed some special handling to read phase current which I'm not seeing in the driver. So I would like to understand how the chip was tested? Anyways, if Fred is ok with it I can just finish what I'm doing and send the patches. It would make sense to have something more complete on submission but I don't want to just "steal" the work already done. - Nuno Sá > > Thanks, > Guenter >