From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-wm2-f13.google.com (mail-wm2-f13.google.com [74.125.225.141]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 46BA43EC827 for ; Fri, 2 Oct 2026 07:29:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=74.125.225.141 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790926145; cv=none; b=nMrMhVAKo/zm1H8TXPVaOmYOX+37Ng2EWHLvcZp5Jc1KjGzyFJL01pMThn/+lNVm4PmMS7X2DT5fCMbn/kTFP4kFK7U+SIZJDqVtgyLa/ifYxFRZDUdyBiuGyMI+s6Ldcyz0b4Bby2Sa6QNKZr8ntSYugJfrROPT2W7UKDStxsk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790926145; c=relaxed/simple; bh=BTuGr8m9qHOpmcjHfKxzvSU/3vPYu8rA2unWoXylLKk=; h=Message-ID:Date:MIME-Version:From:Subject:To:Cc:References: In-Reply-To:Content-Type; b=Dd/dwIy+TbQg5Cd08S5+lahwyxPyXumoIlIgNO44xp9u2eAfAnmsRYQkkPJ+39oa4b5cHichZapHM51BGhHChwDlo5pc40UEHYh2+6zyiHrXyEHRPWT5fgHpJVSFOh3DFkNe2MaZynaqUE75f/ntr41zzMAg8V6otgPxfunvHnc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org; spf=pass smtp.mailfrom=linaro.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b=bhKSNBHo; arc=none smtp.client-ip=74.125.225.141 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="bhKSNBHo" Received: by mail-wm2-f13.google.com with SMTP id 5b1f17b1804b1-4a11603310fso1835455e9.1 for ; Fri, 02 Oct 2026 00:29:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1790926141; x=1791530941; darn=vger.kernel.org; h=content-transfer-encoding:content-type:in-reply-to:organization :autocrypt:content-language:references:cc:to:subject:reply-to:from :user-agent:mime-version:date:message-id:from:to:cc:subject:date :message-id:reply-to:content-type; bh=6zplr7QU6lV0JIsmwOjHD1EDA7HxZc99c9t5ZOt0FqI=; b=bhKSNBHoAMMnzGX7ZcGPXEO4IE47Ndm51W5xr/hzwzpiypx7FC5CfkYK+Kt87JVpQJ /QJosLMTALfrEVEhFCXcdAS1G9h9spnUj4KuxCEDblLtrfUVg4tvXdmotnJI/oP7GuRe ennf0DeKkC4v6rQ/HW4bb458+0+QeuwGAluRstIcsqABFH/AbFXpV0FZ7GqxxcBgRzBj b2BlhCGJVgL9n8Cp4hU0EHXk4uRwBb2PJrCBXlmw338T0qsJz5bUqCM+Cj2BiFMW67cI 7KmvaFREUd9aDsWFdrS7IaBOXKHyQv9LJrT1DOBQddrm/6Wb4ZxRyhqeLNpCxbbnnBqS EiuQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20260707; t=1790926141; x=1791530941; h=content-transfer-encoding:content-type:in-reply-to:organization :autocrypt:content-language:references:cc:to:subject:reply-to:from :user-agent:mime-version:date:message-id:x-gm-gg:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to:content-type; bh=6zplr7QU6lV0JIsmwOjHD1EDA7HxZc99c9t5ZOt0FqI=; b=QaBxItEIuTKJoJKFnNGj7+Anq/SpZxjHb3sEu6aSPc4KD6C8njjUfN/BV4IB9Wi0CT jSYA9fmvYiCB/OODvztvdWQge4S0ycaOFCJv6afHXsdyCytjj6qpAcYfiM7xFk5eAi28 1WeM5NDyshHI+PW2CDL0QurbfDkrYdwQlfwWSAK9JstOVk6GTtmR6eKKvRK9ccmMpBAi aBeurgOjtbUPGMNnHkiqKDfS0L9gm86HpwxA7KzNqR4bj0akXCgB6mma/qWEtl7iQf/S byvhkJ5csC1AfA/RAflzhc1MCrkJx5FdMqzBNaxwKgTWpV616nC9SMDzPU7x19KyoYX1 cYjA== X-Forwarded-Encrypted: i=1; AKwUvBzOlpQlKgarxuxUJCJeh4OLFD2tPLQtSbSRjmhh1VRUxJbFGbqcBvrenSQ19IOjwmo+H3DfhwMKJSKnU/4=@vger.kernel.org X-Gm-Message-State: AFuF++lgn9iIzZT5us0JkU/EQeW9kukrGEDI+7A7YGR6QGZvkU5W70cC gzCcczq7jYtErQWLcbc0OX+jo0XYZIodc0sQ6DEl8ArXyU5mH1KN+St3HahJcQF7PUQ= X-Gm-Gg: AYBFou2szTnr1B2dfgYLSY0iFzsn7ih3ddVJEqAi/6JmNxOIBbJVygdDBj8LKz4lT3h zwK2rixxhw4HHo1NIMmzGy/NWQ/tYjNplOKE2AXmjTjs1uyfpwwF9QvPHhUEP8TfEy/mCNZUICj b23mQJlR30crCbDWJ5flcidMoAcGYF306+1ioluc+u+RmxpMbEd4YJ9lZVr0R2ZxQ3ZpaEvXrY4 YdF8w2HASdKCJWrvJt43iVcx7R09Gp4lG51nA1GmWFvhrfjRoWcCQvLy41jtRtvcjz7wydBeATm xvSPh7Ha+Lbt+OBWlnhBoGTdG+g/2p8IfW1nOK9uf+aV7xoUgfE+Q9DrCCDg5tTyVHETReOCi7o ZbPwecVPA+NCfubdTn2DZRJb3NcY+f4H+3uAA2NV1dxoWkFmNRCXSfiMGumU1PFxHkfYbk927Ip kot1rbbCHoTQnXh5lM3nZchSN1Q/bubLsaHfkgcGSwRW+J5ls5B8p3lNxz/zX5T414ETWGH6cbY hopBZtD+85Z5MeLyU14knxDkaecLirogwswtARStlkfUMuYwUhQAHRz9UB1Ww== X-Received: by 2002:a05:600c:1911:b0:499:b65e:49c9 with SMTP id 5b1f17b1804b1-4a02756643dmr30178595e9.10.1790926141218; Fri, 02 Oct 2026 00:29:01 -0700 (PDT) Received: from ?IPV6:2a01:e0a:106d:1080:2f62:6d3:721b:8c9e? ([2a01:e0a:106d:1080:2f62:6d3:721b:8c9e]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4a039505568sm42454685e9.3.2026.10.02.00.28.59 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 02 Oct 2026 00:29:00 -0700 (PDT) Message-ID: Date: Fri, 2 Oct 2026 09:28:59 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird From: Neil Armstrong Reply-To: Neil Armstrong Subject: Re: [PATCH 1/6] dt-bindings: display: Add panel-mipi-dsi-bpf generic panel binding To: Maxime Ripard Cc: Rob Herring , Jessica Zhang , David Airlie , Simona Vetter , Maarten Lankhorst , Thomas Zimmermann , Krzysztof Kozlowski , Conor Dooley , Nathan Chancellor , Nick Desaulniers , Bill Wendling , Justin Stitt , Florian Fainelli , Broadcom internal kernel review list , Andrzej Hajda , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Luca Ceresoli , Albert Esteve , Dave Stevenson , Javier Martinez Canillas , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, llvm@lists.linux.dev, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Benjamin Tissoires References: <20260928-drm-mipi-dsi-panel-ebpf-v1-0-5244926aace4@kernel.org> <20260928-drm-mipi-dsi-panel-ebpf-v1-1-5244926aace4@kernel.org> <20260928204059.GA515872-robh@kernel.org> <742d5bab-51cc-49f0-825a-f299a055bb1e@linaro.org> Content-Language: en-US, fr Autocrypt: addr=neil.armstrong@linaro.org; keydata= xsBNBE1ZBs8BCAD78xVLsXPwV/2qQx2FaO/7mhWL0Qodw8UcQJnkrWmgTFRobtTWxuRx8WWP GTjuhvbleoQ5Cxjr+v+1ARGCH46MxFP5DwauzPekwJUD5QKZlaw/bURTLmS2id5wWi3lqVH4 BVF2WzvGyyeV1o4RTCYDnZ9VLLylJ9bneEaIs/7cjCEbipGGFlfIML3sfqnIvMAxIMZrvcl9 qPV2k+KQ7q+aXavU5W+yLNn7QtXUB530Zlk/d2ETgzQ5FLYYnUDAaRl+8JUTjc0CNOTpCeik 80TZcE6f8M76Xa6yU8VcNko94Ck7iB4vj70q76P/J7kt98hklrr85/3NU3oti3nrIHmHABEB AAHNKk5laWwgQXJtc3Ryb25nIDxuZWlsLmFybXN0cm9uZ0BsaW5hcm8ub3JnPsLAkQQTAQoA OwIbIwULCQgHAwUVCgkICwUWAgMBAAIeAQIXgBYhBInsPQWERiF0UPIoSBaat7Gkz/iuBQJk Q5wSAhkBAAoJEBaat7Gkz/iuyhMIANiD94qDtUTJRfEW6GwXmtKWwl/mvqQtaTtZID2dos04 YqBbshiJbejgVJjy+HODcNUIKBB3PSLaln4ltdsV73SBcwUNdzebfKspAQunCM22Mn6FBIxQ GizsMLcP/0FX4en9NaKGfK6ZdKK6kN1GR9YffMJd2P08EO8mHowmSRe/ExAODhAs9W7XXExw UNCY4pVJyRPpEhv373vvff60bHxc1k/FF9WaPscMt7hlkbFLUs85kHtQAmr8pV5Hy9ezsSRa GzJmiVclkPc2BY592IGBXRDQ38urXeM4nfhhvqA50b/nAEXc6FzqgXqDkEIwR66/Gbp0t3+r yQzpKRyQif3OwE0ETVkGzwEIALyKDN/OGURaHBVzwjgYq+ZtifvekdrSNl8TIDH8g1xicBYp QTbPn6bbSZbdvfeQPNCcD4/EhXZuhQXMcoJsQQQnO4vwVULmPGgtGf8PVc7dxKOeta+qUh6+ SRh3vIcAUFHDT3f/Zdspz+e2E0hPV2hiSvICLk11qO6cyJE13zeNFoeY3ggrKY+IzbFomIZY 4yG6xI99NIPEVE9lNBXBKIlewIyVlkOaYvJWSV+p5gdJXOvScNN1epm5YHmf9aE2ZjnqZGoM Mtsyw18YoX9BqMFInxqYQQ3j/HpVgTSvmo5ea5qQDDUaCsaTf8UeDcwYOtgI8iL4oHcsGtUX oUk33HEAEQEAAcLAXwQYAQIACQUCTVkGzwIbDAAKCRAWmrexpM/4rrXiB/sGbkQ6itMrAIfn M7IbRuiSZS1unlySUVYu3SD6YBYnNi3G5EpbwfBNuT3H8//rVvtOFK4OD8cRYkxXRQmTvqa3 3eDIHu/zr1HMKErm+2SD6PO9umRef8V82o2oaCLvf4WeIssFjwB0b6a12opuRP7yo3E3gTCS KmbUuLv1CtxKQF+fUV1cVaTPMyT25Od+RC1K+iOR0F54oUJvJeq7fUzbn/KdlhA8XPGzwGRy 4zcsPWvwnXgfe5tk680fEKZVwOZKIEuJC3v+/yZpQzDvGYJvbyix0lHnrCzq43WefRHI5XTT QbM0WUIBIcGmq38+OgUsMYu4NzLu7uZFAcmp6h8g Organization: Linaro In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 10/1/26 09:09, Maxime Ripard wrote: > On Wed, Sep 30, 2026 at 03:32:19PM +0200, Neil Armstrong wrote: >> On 9/29/26 10:39, Maxime Ripard wrote: >>> Hi, >>> >>> >> >> >>> >>> panel-mipi-dsi-spi is a generic panel that will load a firmware, and >>> quite similar to this one. google,android-pipe and qcom,fastrpc don't >>> attach to anything and will just open a tunnel to userspace, which is >>> somewhat equivalent but more dramatic than what this driver is doing. >>> simple-card or its variations will just instantiate a kernel driver from >>> the DT and is used pretty much everywhere. >>> >>> I reused the binding from panel-mipi-dsi-spi for this. It was reviewed >>> by rob, and acked by a panel maintainer, and 4 years ago, so we're way >>> past the "oh but we didn't know what we were doing back then" argument. >>> >>> So, let's phrase this differently: what's different about the >>> description than panel-mipi-dsi-spi, or any other binding already in >>> tree? >> >> The panel-mipi-dsi-spi still describes a class of H/W control interface, >> not a pure software driver implementation type. >> >> "panel-mipi-dsi-bpf" or "panel-mipi-dsi-rust" or "panel-mipi-dsi-cplusplus" >> would be the same problem. > > Rob explicitly said the bpf part wasn't the problem. Also, I don't care > for the compatible itself, so what would be an acceptable compatible for > you? > >>> If it's the BPF part, BPF is not Linux-only, and there's hardware with >>> direct BPF support these days, so it can be considered OS-agnostic and >>> not an implementation detail. >> >> If somehow panels used a standardized MIPI firmware we could define this >> in DT, but here we're basically inventing our own type of firmware from >> thin air. > > That's not what panel-mipi-dsi-spi is. What you describe is how it's implemented in software Neil > > Maxime