From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 C8528331EDD; Thu, 30 Jul 2026 06:18:06 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785392298; cv=none; b=dlmMBXONq6FL4vFXFGIBi64tXHI0svf5qGQG2wtv8PRUHgPoq+BTWeEtiGlSS6CTrkuR6CEhN53oNzGnkFftWLy3gLno8fUzD+IipJ2Ulb5bEUh9eIwpTkeO7cn0SZHyQtgxIHQ8vNTQiBhcDF4LHZdzI8EsktoCcZNFefCTIJ8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785392298; c=relaxed/simple; bh=l62V11cowrqeI8BnXl99ue73qOhyR2JHYebtAXEeqAg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=e+vjqxBj6jpkvYtlhhTn5AF4Jcb+kS+mEBojrHBmhzuSpZQnfH2beXx1gcpqlSyYckkE19UTX8tRkFl28KmqtLIDBvQeYB4qL/u2ZvMr3xfF9/zozGVNzlkkWFjzKKgyeYah8MW/qyTnhRhRcSBy5TrGQUJZLl4KM11Cqroypto= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=Fzzop7oK; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="Fzzop7oK" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DBA261F000E9; Thu, 30 Jul 2026 06:18:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1785392285; bh=Jp+eBZgiwD0pRTnxUq82s1K5W+2JyXhDd+iXNbrfcvk=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=Fzzop7oKjJ0Rqj2Dgo594sxMQB/hn3b1TZ+1TdWBybJ72SFytz1AdKjyJhnTNA2EM M1Rt4ksHmDUFR/hWfUAfYpyWmmgbPTPCpw5oWRGMQXFyLQzCt5AVkCPDNPIhsGNz3o f0wCn2gR3mCJqUtWAjLLqcAd7S2y1iPGfP3CdpMe0Mn23Qc3Ca4xMINGywzX5nuYS5 mLSwxLiJ/3vTMygoFRCcIcEBaIWLQ3ksMlreqnOrkHy688wkW9Yv/e+CmDmOfjGHvd x95Qq15fHfq7clRzqrgHmXvqsN9e7O8UtI4NeqhRTYibcTUF+4UwWyRAoPDzy+59Bq Qu1jvQeLrwr7g== Message-ID: <6cc03c4c-2d88-46f2-aee4-adb769d10cbd@kernel.org> Date: Thu, 30 Jul 2026 08:17:57 +0200 Precedence: bulk X-Mailing-List: linux-hwmon@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [hwmon-next PATCH v3 1/4] dt-bindings: hwmon: adi,adt7470 To: Luiz Angelo Daros de Luca Cc: Guenter Roeck , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Chris Packham , Andrew Morton , "Darrick J. Wong" , =?UTF-8?Q?Uwe_Kleine-K=C3=B6nig?= , linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pwm@vger.kernel.org References: <20260728-adt7470_thermalzone-v3-0-d4586478cdba@gmail.com> <20260728-adt7470_thermalzone-v3-1-d4586478cdba@gmail.com> <20260728-meteoric-quixotic-sunfish-0de2cb@quoll> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; keydata= xsFNBFVDQq4BEAC6KeLOfFsAvFMBsrCrJ2bCalhPv5+KQF2PS2+iwZI8BpRZoV+Bd5kWvN79 cFgcqTTuNHjAvxtUG8pQgGTHAObYs6xeYJtjUH0ZX6ndJ33FJYf5V3yXqqjcZ30FgHzJCFUu JMp7PSyMPzpUXfU12yfcRYVEMQrmplNZssmYhiTeVicuOOypWugZKVLGNm0IweVCaZ/DJDIH gNbpvVwjcKYrx85m9cBVEBUGaQP6AT7qlVCkrf50v8bofSIyVa2xmubbAwwFA1oxoOusjPIE J3iadrwpFvsZjF5uHAKS+7wHLoW9hVzOnLbX6ajk5Hf8Pb1m+VH/E8bPBNNYKkfTtypTDUCj NYcd27tjnXfG+SDs/EXNUAIRefCyvaRG7oRYF3Ec+2RgQDRnmmjCjoQNbFrJvJkFHlPeHaeS BosGY+XWKydnmsfY7SSnjAzLUGAFhLd/XDVpb1Een2XucPpKvt9ORF+48gy12FA5GduRLhQU vK4tU7ojoem/G23PcowM1CwPurC8sAVsQb9KmwTGh7rVz3ks3w/zfGBy3+WmLg++C2Wct6nM Pd8/6CBVjEWqD06/RjI2AnjIq5fSEH/BIfXXfC68nMp9BZoy3So4ZsbOlBmtAPvMYX6U8VwD TNeBxJu5Ex0Izf1NV9CzC3nNaFUYOY8KfN01X5SExAoVTr09ewARAQABzSVLcnp5c3p0b2Yg S296bG93c2tpIDxrcnprQGtlcm5lbC5vcmc+wsGPBBMBCgA5AhsDBgsJCAcDAgYVCAIJCgsE FgIDAQIeAQIXgBYhBJvQfg4MUfjVlne3VBuTQ307QWKbBQJp2mE8AAoJEBuTQ307QWKbeaIP /ihHTkTW4KsN/DQ945JJbyu5tI0J80Wue7QyyLPglyKfhgb5cLLNPpOC8cCIJsc7+W3i2P38 s2c1cOH6CYGE7E9ur3Vfme8NW2S2I/Z8VC7bZnzyS23wT17LrsdS/qCpx4o8U+pt/xdXDKph EGRYrIEmMpUWvyYzyYKGIe25FtaayIIKpq8eZYyFcp2f/sG5IkOW5uZzHPMPdcm87jU7fyuQ rAU2vx9r+ulUfQ/q9Z2roC/ode3l7t2pN7BCBCsUDp6JCrUyZrtT1e7EbA0ZRP3aOBNk2P2E DQOgJGjGdO5Yx2Y9LFtltu6JbsBJHi1syGRX3AtQYOMc4Y1WGoeZJmMlvKj2ZqqXNkcWi2DS IQEWB0uW6CqFsBBIMGDa+6OzdaVO/uAVXWDWml02Men3CILdI1MbVjoh8ECqYUY7OQ+JJvNN vnliuq5WM3Ghd3jg/LZZrxXjdIginRHFQCjIJYLKpLZWm1/iDFedcfzqRNYmTtqscdCNHW41 oT3Z7BmO9xwdjuwBS6nmS6JJwkbf5Ot2QR4pB/DRU7ZwjT1qHe+9r9gF32wXVQatHNGK/VVu sfwOnkdxCWkp/qb2gdQRmZh+SedStWshigH6sNfuHBloF/q+hjMRc8b2m326OZdrbSHwY1Sz vti8Hn7n8NjdHO9LKB7BIdjkA9DA5WsqOuVCzsFNBFVDXDQBEADNkrQYSREUL4D3Gws46JEo Z9HEQOKtkrwjrzlw/tCmqVzERRPvz2Xg8n7+HRCrgqnodIYoUh5WsU84N03KlLueMNsWLJBv BaubYN4JuJIdRr4dS4oyF1/fQAQPHh8Thpiz0SAZFx6iWKB7Qrz3OrGCjTPcW6eiOMheesVS 5hxietSmlin+SilmIAPZHx7n242u6kdHOh+/SyLImKn/dh9RzatVpUKbv34eP1wAGldWsRxb f3WP9pFNObSzI/Bo3kA89Xx2rO2roC+Gq4LeHvo7ptzcLcrqaHUAcZ3CgFG88CnA6z6lBZn0 WyewEcPOPdcUB2Q7D/NiUY+HDiV99rAYPJztjeTrBSTnHeSBPb+qn5ZZGQwIdUW9YegxWKvX XHTwB5eMzo/RB6vffwqcnHDoe0q7VgzRRZJwpi6aMIXLfeWZ5Wrwaw2zldFuO4Dt91pFzBSO IpeMtfgb/Pfe/a1WJ/GgaIRIBE+NUqckM+3zJHGmVPqJP/h2Iwv6nw8U+7Yyl6gUBLHFTg2h YnLFJI4Xjg+AX1hHFVKmvl3VBHIsBv0oDcsQWXqY+NaFahT0lRPjYtrTa1v3tem/JoFzZ4B0 p27K+qQCF2R96hVvuEyjzBmdq2esyE6zIqftdo4MOJho8uctOiWbwNNq2U9pPWmu4vXVFBYI GmpyNPYzRm0QPwARAQABwsF2BBgBCgAgAhsMFiEEm9B+DgxR+NWWd7dUG5NDfTtBYpsFAmna YUkACgkQG5NDfTtBYptX+BAApg32CkxwNucNEi8WfWA8oKkW0y8YDuY6ORMo9FWNGiT/OTy0 vyJrLocrpn86zwfjVp+eCrssPYh8eqJfnWqmYv6ACQtHPYzPZQ3mSo8H97Z01oUxITzCxpXm ZkLgPIqtDPcC2E3dPM/fVxcyowM8XsaMA9wcsaUYrta8toOq2b9tKcjleKMfMrm0gQ9u7wUc QbLkwj6TCLOwucb07GXzLTNF9PZmaDUpKAZjMjmrW+le+SFvQbhamx0rxLWPR0NWntXpbCn+ +ACch03p/JyTBVktxFsFyCt7pTPE1kEaeuXBTe/a2D9iQvRxRW19LvuO2e59/u1wYUiH/orz wbIC2S4dBsPAPihL3ztOU1yE86GPyQtSE0kU+/7snnLt4QGi6PChf3t5gnNjAzjUUovO8rgI c+5yN5heq5loYHgK6OQ9OlHzsPHO9e9MOQcKlFycs1pyijFGzDwdNUm/SchK8iWT2QApTx4A K9bCVaboTA2T77QYkRcRJYSsO1alGX0ome/hMLD1daXlkrNUp1HWa3K4iytLRXjCSIorWiGs n+q3krnpXu3TFkA8qtOFZMdnIiFuiq1yLT8hptsV5xh1TA2nsVvSYiaCr3q4s4BKjS/KrLDb qoxzw8ISjdUp4pA85vb6YLCmb39NgidD+7PmAr65lBNveIFynTgsja1rRQ4= In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 29/07/2026 06:45, Luiz Angelo Daros de Luca wrote: > Hi Krzysztof, > > Thanks for the review. > >> On Tue, Jul 28, 2026 at 12:07:09AM -0300, Luiz Angelo Daros de Luca wrote: >>> The Analog Devices ADT7470 is a multichannel temperature sensor and >>> PWM fan controller. It supports monitoring up to 10 external >>> temperature sensors and controlling up to 4 fans. >>> >>> Add the device tree binding documentation for it. This includes >>> support for the thermal framework by defining the "#thermal-sensor-cells" >>> property, and models the fan control lines as PWM channels by >>> defining the "#pwm-cells" property. >>> >>> Signed-off-by: Luiz Angelo Daros de Luca >>> --- >>> .../devicetree/bindings/hwmon/adi,adt7470.yaml | 55 ++++++++++++++++++++++ >>> 1 file changed, 55 insertions(+) >>> >>> diff --git a/Documentation/devicetree/bindings/hwmon/adi,adt7470.yaml b/Documentation/devicetree/bindings/hwmon/adi,adt7470.yaml >>> new file mode 100644 >>> index 000000000000..bb2375a4a490 >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/hwmon/adi,adt7470.yaml >>> @@ -0,0 +1,55 @@ >>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) >>> +%YAML 1.2 >>> +--- >>> +$id: http://devicetree.org/schemas/hwmon/adi,adt7470.yaml# >>> +$schema: http://devicetree.org/meta-schemas/core.yaml# >>> + >>> +title: Analog Devices ADT7470 hwmon sensor >>> + >>> +maintainers: >>> + - Luiz Angelo Daros de Luca >>> + >>> +description: >>> + Multi-channel temperature monitor and PWM fan controller. >>> + It supports monitoring up to 10 external temperature sensors and >>> + controlling up to four fans. The fan control lines are modeled >>> + as standard PWM channels. >>> + >>> +properties: >>> + compatible: >>> + const: adi,adt7470 >>> + >>> + reg: >>> + maxItems: 1 >>> + >>> + "#pwm-cells": >>> + const: 3 >>> + description: >>> + See Documentation/devicetree/bindings/pwm/pwm.yaml for the >>> + generic PWM binding description. >> >> Drop description. >> >> You OTOH, miss ref to pwm schema. Referencing here in description should >> raise you questions... And then use unevaluatedProperties. > > I will drop the description and change to `unevaluatedProperties: false`. > > Regarding the reference to the PWM schema, adding `$ref: > /schemas/pwm/pwm.yaml#` enforces the `$nodename` to match > `^pwm(@.*|-([0-9a-f]+))?$`. Since the ADT7470 is primarily a hardware > monitor, its node is typically named `sensor@...`, > `fan-controller@...` or `hwmon@...`. Importing `pwm.yaml` causes > `dtbs_check` to fail on existing node names because of this mismatch. If it is a fan-controller then it should use common fan schema, because you might be missing several properties. Device having PWM outputs alone does not make it a fan controller, though. > > Since we cannot override the `$nodename` from an imported schema, what > is the preferred approach here? Should I skip the `$ref` to `pwm.yaml` > in this specific case, or is there an accepted workaround for sensors > acting as PWM providers? You can skip the pwm.yaml in such case. > >> You most likely miss ref to thermal-sensor.yaml as well, but that would >> change the ABI since hwmon would fail on missing cells, right? > > Yes, you are right. It would require #thermal-sensor-cells and the > device might not have a thermal sensor connected if it is used as a > pure fan controller. Likewise, it can also be used as a simple > analog-to-digital temperature adapter, with no fans connected (and > "#pwm-cells" might be missing). > > To address this without breaking the ABI, we could add the ref > conditionally if "#thermal-sensor-cells" is present. > > allOf: > - if: > required: > - "#thermal-sensor-cells" > then: > $ref: /schemas/thermal/thermal-sensor.yaml# > > I just don't know if it is ok to ref thermal-sensor but not pwm. Feels ok. Best regards, Krzysztof