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 81C8E2D73B3; Mon, 27 Oct 2025 18:01:52 +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=1761588113; cv=none; b=D59MQRslpDNpghp4sgUXPuuvK4pJJrthhQSgNV84zyx4l9S/URPcWYySOWGS8RH7KMhDBYjFC6Q61Mkt6hIZ7x+wYsAySpfUNdFXey+YN1MPVHGUtzWMTxmMfI+taTs+6uo55pXaVqwYgPWB+9E03nKTAV77GiGuQOnD4sDy//0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1761588113; c=relaxed/simple; bh=FzhkkPx/bJH57tjT+tQuLUmnAYh7kimWNyLeFkyJm2g=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=i1Y0/8AY9AaKqKu6etrXH+uqLAS5GBqOrPK7vpNQX8oxs1J0+oHjXieJcyaujaVxN+se4tfRvVOJts7ujPUUfclrWk1w5yvC6D4RlG6eLNgeUMTbQfBMQ1FduIH6OF8IvaaPqNuBNloTuCL0mknoJF6WNsMwwTTz80lSctfjX/s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=QQFuoY6s; 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="QQFuoY6s" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4CA6AC4CEF1; Mon, 27 Oct 2025 18:01:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1761588112; bh=FzhkkPx/bJH57tjT+tQuLUmnAYh7kimWNyLeFkyJm2g=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=QQFuoY6sOPhRmbUaIIYGwELjo037kSApUYRJs+P3EQqCdDBecvGL5xDPX+E7Pe3eX NPpObbBuncxo0rBnfO9rpv71PnBBaYt1mYR1/JzZqKplaJorhf1OgHpOZPzL17zsrr PiKLqiT6q5LLGqnbO+NxbEpztdNm0NbzJ5Fr8uZwVJEP9dllYX3sfTltvRfVQiXHUC 6lwMushn+ymlRRFNEn32wtHRiWmfX8XCWrGCz9nC6QHoa02QRmDljNPqOx0AsAnqLV m9DLUUs9NC3B/vnBAt7fHiJz7NvhJUaB0sVITCYNN7/NChH5U8C+VHmi/LZWkW7vx3 3eRSZou3PZjtg== Message-ID: Date: Mon, 27 Oct 2025 19:01:47 +0100 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/2] dt-bindings: hwmon: Add support for ST TSC1641 power monitor To: Guenter Roeck , Igor Reznichenko Cc: conor+dt@kernel.org, corbet@lwn.net, david.hunter.linux@gmail.com, devicetree@vger.kernel.org, krzk+dt@kernel.org, linux-doc@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-kernel@vger.kernel.org, robh@kernel.org, skhan@linuxfoundation.org References: <408c1698-a8ad-4e16-8def-352c2c265f5a@kernel.org> <20251026184641.631641-1-igor@reznichenko.net> <112db7fd-3c0e-4c56-a553-5aca12965bdf@kernel.org> <0dfcfcde-d207-44af-ae7f-d90d623bac02@roeck-us.net> From: Krzysztof Kozlowski Content-Language: en-US Autocrypt: addr=krzk@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit On 27/10/2025 17:53, Guenter Roeck wrote: > On 10/27/25 01:40, Krzysztof Kozlowski wrote: >> On 26/10/2025 20:58, Guenter Roeck wrote: >>>>>>> + reg: >>>>>>> + maxItems: 1 >>>>>>> + >>>>>>> + shunt-resistor-micro-ohms: >>>>>>> + description: Shunt resistor value in micro-ohms. Since device has internal >>>>>>> + 16-bit RSHUNT register with 10 uOhm LSB, the maximum value is capped at >>>>>>> + 655.35 mOhm. >>>>>>> + minimum: 100 >>>>>>> + default: 1000 >>>>>>> + maximum: 655350 >>>>>>> + >>>>>>> + st,alert-polarity-active-high: >>>>>> >>>>>> Isn't this just interrupt? You need proper interrupts property and then >>>>>> its flag define the type of interrupt. >>>>> >>>>> This controls a bit written into device register. >>>>> I omitted interrupt property after looking at existing power monitor bindings, >>>>> especially hwmon/ti,ina2xx.yaml. INA226 has very similar bit controlling alert >>>>> pin polarity and binding doesn't define alert pin as interrupt. Overall, I didn't >>>>> find many power monitor bindings defining alert pins as interrupts. >>>> >>>> >>>> On INA2xx that's SMBUS Alert. Is this the case here as well? >>>> >>> >>> It could be wired to SMBus alert, or it could be wired to a CPU interrupt pin. >> >> So please explain me why CPU interrupt pin, which in every really every >> device called "interrupts", would not be "interrupts" here? How CPU can >> even guess the number of the interrupt in such case, without >> "interrupts" property? >> > > I thought we were discussing the need for the st,alert-polarity-active-high > property, sorry. Yes, we kind of do, I am just trying to understand what is expressed here. If this is a CPU interrupt, its flags should mark the proper signal level, including inverter. If this is something else (or both), then this property might make sense, I just don't know what is this. Best regards, Krzysztof