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 36A59323E for ; Fri, 22 Sep 2023 21:06:33 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C0E40C433C8; Fri, 22 Sep 2023 21:06:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1695416793; bh=oeSNGT5vCeLS0tK5r0KuFqwwS5mmgSj+Xv6+izXXJKY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=eLt6MevgEBW3Z4+5Z8SmfiOWQovihSSaExBMeCLCIYBRWnlFSXQ5ShsVRjWDnK2hg KuXc1TrMJAuofUqH7yW/NtIsN1z7C1m9SThRO3JHYN+9QBoITy5V+wFxvYLRsI2bDy A8E+Lc4xe99m0HAYGVfrIvB71Ug+EiTj5j75YSX4RKFvU5p4iqnADSm6+2Sgek6tf3 e0ibQy0x4lUEuh7S7pIqA9jPgmwXL37y9cMSSpwkJHugxoP+MXQLsiabF87rsn0Lgk z9qhVH/tM7x3hTcocBZso/tSXc53NLZ3/x5nR7iEcsOw4E0NTLpIHLEa1G7bZVgHmy m0HonfAwQBSKQ== Received: (nullmailer pid 3599452 invoked by uid 1000); Fri, 22 Sep 2023 21:06:31 -0000 Date: Fri, 22 Sep 2023 16:06:31 -0500 From: Rob Herring To: Jon Hunter Cc: Jean Delvare , Guenter Roeck , Krzysztof Kozlowski , Conor Dooley , Thierry Reding , linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org, linux-tegra@vger.kernel.org, Ninad Malwade Subject: Re: [PATCH V3 2/4] dt-bindings: hwmon: ina3221: Add ti,summation-disable Message-ID: <20230922210631.GA3569506-robh@kernel.org> References: <20230921130818.21247-1-jonathanh@nvidia.com> <20230921130818.21247-3-jonathanh@nvidia.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=us-ascii Content-Disposition: inline In-Reply-To: <20230921130818.21247-3-jonathanh@nvidia.com> On Thu, Sep 21, 2023 at 02:08:16PM +0100, Jon Hunter wrote: > The INA3221 has a critical alert pin that can be controlled by the > summation control function. This function adds the single > shunt-voltage conversions for the desired channels in order to > compare the combined sum to the programmed limit. The Shunt-Voltage > Sum Limit register contains the programmed value that is compared > to the value in the Shunt-Voltage Sum register in order to > determine if the total summed limit is exceeded. If the > shunt-voltage sum limit value is exceeded, the critical alert pin > pulls low. > > For the summation limit to have a meaningful value, it is necessary > to use the same shunt-resistor value on all included channels. Add a new > vendor specific property, 'ti,summation-disable', to allow specific > channels to be excluded from the summation control function if the shunt > resistor is different to other channels or the channel should not be > considered for triggering the critical alert pin. You are adding this feature to the driver, but requiring a new property to disable it. So what happens with an existing user (old DT) and a kernel with the new feature? Rob