From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from ixit.cz (ip-89-177-23-149.bb.vodafone.cz [89.177.23.149]) (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 4BECE2F3B; Fri, 28 Mar 2025 22:45:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=89.177.23.149 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743201944; cv=none; b=EOo0wSw2Y+ijmIrvHt5KdKtmBNxYcXgVKrm7qRfyM38kNZMnwvOrtHYvAUbvh+Q/mucNP/htKnXk9ngbNmlYIEZHxkBv6hgx2+bxHFQHZ6IsVKt82zaBHj75uiO+d08LBVKOVqj50eJcDSvA5seG5cU8il0u4hCQynEqrXAG3ZM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743201944; c=relaxed/simple; bh=OcmzUyTaRF6a7oAZk74SPlrpzwzA9+O6RXsauqUGSZ0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=YwO6e3cocJhqsg84aHUllrh6+t0mLDqhXSSqmYI/63hwc3a39klz0g8dW/K2z0iZgEbvxSO/9ob3/1vqF4ZAejVYmWmwQMArIWMCTNvVI1/hUy84EZ7HEh7Jva8f4DyOEY8Uzb+d7WVBz1gPIf7aLSdrGvRiP8MObLYcd2D5FDw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ixit.cz; spf=pass smtp.mailfrom=ixit.cz; dkim=pass (1024-bit key) header.d=ixit.cz header.i=@ixit.cz header.b=Zupk23Ju; arc=none smtp.client-ip=89.177.23.149 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ixit.cz Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ixit.cz Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ixit.cz header.i=@ixit.cz header.b="Zupk23Ju" Received: from [10.0.0.200] (unknown [10.0.0.1]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by ixit.cz (Postfix) with ESMTPSA id 24456161DE4; Fri, 28 Mar 2025 23:45:38 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ixit.cz; s=dkim; t=1743201938; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:autocrypt:autocrypt; bh=ueanIGtjkpCvr6vLEp+EZHKgAfewBOlZIvgYT7X3d1s=; b=Zupk23Juu1CpUdhm9IlBU5A/T7hQR0M9o9JH5u9xVYP+CAl1Ax2HFgpjfZTKbw0v/iEB3i WyJyzXPtur4juwum35OwiOLrvciDn6EuyLhWq2B89MpXNC3ihXCV3x0hPCvwQYO4HMyi5t K9xFYq8LAXie3XcRyzSeIqx620+7Xbk= Message-ID: <2d555c27-1cb1-4ea9-9327-e1a3774e103b@ixit.cz> Date: Fri, 28 Mar 2025 23:45:37 +0100 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 1/7] dt-bindings: input: syna,rmi4: document syna,pdt-fallback-desc To: Caleb Connolly , Krzysztof Kozlowski Cc: Dmitry Torokhov , Rob Herring , Krzysztof Kozlowski , Conor Dooley , "Jason A. Donenfeld" , Matthias Schiffer , Vincent Huang , linux-input@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, phone-devel@vger.kernel.org, ~postmarketos/upstreaming@lists.sr.ht References: <20250308-synaptics-rmi4-v3-0-215d3e7289a2@ixit.cz> <20250308-synaptics-rmi4-v3-1-215d3e7289a2@ixit.cz> <20250310-hissing-vagabond-pegasus-cc8aed@krzk-bin> <3c5e12fc-eb91-46e8-a558-9896f0bdcab4@ixit.cz> <48bb62eb-8aa9-465c-9e77-c0b375df0c9f@linaro.org> <492da0ab-3a5c-4ee9-bc37-d66b007ffd81@kernel.org> <5060c248-3160-4d52-81ec-8e06bbd246bf@linaro.org> Content-Language: en-US From: David Heidelberg Autocrypt: addr=david@ixit.cz; keydata= xsFNBF5v1x4BEADS3EddwsNsvVAI1XF8uQKbdYPY/GhjaSLziwVnbwv5BGwqB1tfXoHnccoA 9kTgKAbiXG/CiZFhD6l4WCIskQDKzyQN3JhCUIxh16Xyw0lECI7iqoW9LmMoN1dNKcUmCO9g lZxQaOl+1bY/7ttd7DapLh9rmBXJ2lKiMEaIpUwb/Nw0d7Enp4Jy2TpkhPywIpUn8CoJCv3/ 61qbvI9y5utB/UhfMAUXsaAgwEJyGPAqHlC0YZjaTwOu+YQUE3AFzhCbksq95CwDz4U4gdls dmv9tkATfu2OmzERZQ6vJTehK0Pu4l5KmCAzYg42I9Dy4E6b17x6NncKbcByQFOXMtG0qVUk F1yeeOQUHwu+8t3ZDMBUhCkRL/juuoqLmyDWKMc0hKNNeZ9BNXgB8fXkRLWEUfgDXsFyEkKp NxUy5bDRlivf6XfExnikk5kj9l2gGlNQwqROti/46bfbmlmc/a2GM4k8ZyalHNEAdwtXYSpP 8JJmlbQ7hNTLkc3HQLRsIocN5th/ur7pPMz1Beyp0gbE9GcOceqmdZQB80vJ01XDyCAihf6l AMnzwpXZsjqIqH9r7T7tM6tVEVbPSwPt4eZYXSoJijEBC/43TBbmxDX+5+3txRaSCRQrG9dY k3mMGM3xJLCps2KnaqMcgUnvb1KdTgEFUZQaItw7HyRd6RppewARAQABzSBEYXZpZCBIZWlk ZWxiZXJnIDxkYXZpZEBpeGl0LmN6PsLBlAQTAQgAPgIbAwULCQgHAgYVCgkICwIEFgIDAQIe AQIXgBYhBNd6Cc/u3Cu9U6cEdGACP8TTSSByBQJl+KksBQkPDaAOAAoJEGACP8TTSSBy6IAQ AMqFqVi9LLxCEcUWBn82ssQGiVSDniKpFE/tp7lMXflwhjD5xoftoWOmMYkiWE86t5x5Fsp7 afALx7SEDz599F1K1bLnaga+budu55JEAYGudD2WwpLJ0kPzRhqBwGFIx8k6F+goZJzxPDsf loAtXQE62UvEKa4KRRcZmF0GGoRsgA7vE7OnV8LMeocdD3eb2CuXLzauHAfdvqF50IfPH/sE jbzROiAZU+WgrwU946aOzrN8jVU+Cy8XAccGAZxsmPBfhTY5f2VN1IqvfaRdkKKlmWVJWGw+ ycFpAEJKFRdfcc5PSjUJcALn5C+hxzL2hBpIZJdfdfStn+DWHXNgBeRDiZj1x6vvyaC43RAb VXvRzOQfG4EaMVMIOvBjBA/FtIpb1gtXA42ewhvPnd5RVCqD9YYUxsVpJ9d+XsAy7uib3BsV W2idAEsPtoqhVhq8bCUs/G4sC2DdyGZK8MRFDJqciJSUbqA+5z1ZCuE8UOPDpZKiW6H/OuOM zDcjh0lOzr4p+/1TSg1PbUh7fQ+nbMuiT044sC1lLtJK0+Zyn0GwhR82oNM4fldNsaHRW42w QGD35+eNo5Pvb3We5XRMlBdhFnj7Siggp4J8/PJ6MJvRyC+RIJPGtbdMB2/RxWunFLn87e5w UgwR9jPMHAstuTR1yR23c4SIYoQ2fzkrRzuazsFNBF5v1x4BEADnlrbta2WL87BlEOotZUh0 zXANMrNV15WxexsirLetfqbs0AGCaTRNj+uWlTUDJRXOVIwzmF76Us3I2796+Od2ocNpLheZ 7EIkq8budtLVd1c06qJ+GMraz51zfgSIazVInNMPk9T6fz0lembji5yEcNPNNBA4sHiFmXfo IhepHFOBApjS0CiOPqowYxSTPe/DLcJ/LDwWpTi37doKPhBwlHev1BwVCbrLEIFjY0MLM0aT jiBBlyLJaTqvE48gblonu2SGaNmGtkC3VoQUQFcVYDXtlL9CVbNo7BAt5gwPcNqEqkUL60Jh FtvVSKyQh6gn7HHsyMtgltjZ3NKjv8S3yQd7zxvCn79tCKwoeNevsvoMq/bzlKxc9QiKaRPO aDj3FtW7R/3XoKJBY8Hckyug6uc2qYWRpnuXc0as6S0wfek6gauExUttBKrtSbPPHiuTeNHt NsT4+dyvaJtQKPBTbPHkXpTO8e1+YAg7kPj3aKFToE/dakIh8iqUHLNxywDAamRVn8Ha67WO AEAA3iklJ49QQk2ZyS1RJ2Ul28ePFDZ3QSr9LoJiOBZv9XkbhXS164iRB7rBZk6ZRVgCz3V6 hhhjkipYvpJ/fpjXNsVL8jvel1mYNf0a46T4QQDQx4KQj0zXJbC2fFikAtu1AULktF4iEXEI rSjFoqhd4euZ+QARAQABwsF8BBgBCAAmAhsMFiEE13oJz+7cK71TpwR0YAI/xNNJIHIFAmX4 qVAFCQ8NoDIACgkQYAI/xNNJIHKN4A/+Ine2Ii7JiuGITjJkcV6pgKlfwYdEs4eFD1pTRb/K 5dprUz3QSLP41u9OJQ23HnESMvn31UENk9ffebNoW7WxZ/8cTQY0JY/cgTTrlNXtyAlGbR3/ 3Q/VBJptf04Er7I6TaKAmqWzdVeKTw33LljpkHp02vrbOdylb4JQG/SginLV9purGAFptYRO 8JNa2J4FAQtQTrfOUjulOWMxy7XRkqK3QqLcPW79/CFn7q1yxamPkpoXUJq9/fVjlhk7P+da NYQpe4WQQnktBY29SkFnvfIAwqIVU8ix5Oz8rghuCcAdR7lEJ7hCX9bR0EE05FOXdZy5FWL9 GHvFa/Opkq3DPmFl/0nt4HJqq1Nwrr+WR6d0414oo1n2hPEllge/6iD3ZYwptTvOFKEw/v0A yqOoYSiKX9F7Ko7QO+VnYeVDsDDevKic2T/4GDpcSVd9ipiKxCQvUAzKUH7RUpqDTa+rYurm zRKcgRumz2Tc1ouHj6qINlzEe3a5ldctIn/dvR1l2Ko7GBTG+VGp9U5NOAEkGpxHG9yg6eeY fFYnMme51H/HKiyUlFiE3yd5LSmv8Dhbf+vsI4x6BOOOq4Iyop/Exavj1owGxW0hpdUGcCl1 ovlwVPO/6l/XLAmSGwdnGqok5eGZQzSst0tj9RC9O0dXO1TZocOsf0tJ8dR2egX4kxM= In-Reply-To: <5060c248-3160-4d52-81ec-8e06bbd246bf@linaro.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 26/03/2025 11:26, Caleb Connolly wrote: > > > On 3/26/25 07:57, Krzysztof Kozlowski wrote: >> On 25/03/2025 14:23, Caleb Connolly wrote: >>> >>> >>> On 3/25/25 08:36, Krzysztof Kozlowski wrote: >>>> On 24/03/2025 19:00, David Heidelberg wrote: >>>>> On 10/03/2025 10:45, Krzysztof Kozlowski wrote: >>>>>> On Sat, Mar 08, 2025 at 03:08:37PM +0100, David Heidelberg wrote: >>>>>>> From: Caleb Connolly >>>>>>> >>>>>>> This new property allows devices to specify some register values >>>>>>> which >>>>>>> are missing on units with third party replacement displays. These >>>>>>> displays use unofficial touch ICs which only implement a subset >>>>>>> of the >>>>>>> RMI4 specification. >>>>>> >>>>>> These are different ICs, so they have their own compatibles. Why this >>>>>> cannot be deduced from the compatible? >>>>> >>>>> Yes, but these identify as the originals. >>>> >>>> >>>> It does not matter how they identify. You have the compatible for them. >>>> If you cannot add compatible for them, how can you add dedicated >>>> property for them? >>> >>> Hi Krzysztof, >>> >>> There are an unknown number of knock-off RMI4 chips which are sold in >>> cheap replacement display panels from multiple vendors. We suspect >>> there's more than one implementation. >>> >>> A new compatible string wouldn't help us, since we use the same DTB on >>> fully original hardware as on hardware with replacement parts. >>> >>> The proposed new property describes configuration registers which are >>> present on original RMI4 chips but missing on the third party ones, the >>> contents of the registers is static. >> >> >> So you want to add redundant information for existing compatible, while >> claiming you cannot deduce it from that existing compatible... Well, >> no.. you cannot be sure that only chosen boards will have touchscreens >> replaced, thus you will have to add this property to every board using >> this compatible making it equal to the compatible and we are back at my >> original comment. This is deducible from the compatible. If not the new >> one, then from old one. > > hmm I see, so instead we should add a compatible for the specific > variant (S3320 or something) of RMI4 in this device and handle this in > the driver? I think that makes sense. Agree, preparing it for v4. So far proposing `compatible = "syna,rmi4-s3706b-i2c", "syna,rmi4-i2c"` (as S3706B is written in the commit and search confirms it for OP6/6T). David> >> >> Best regards, >> Krzysztof > -- David Heidelberg