From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9FDA0C433ED for ; Fri, 16 Apr 2021 11:41:22 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 22B88610F7 for ; Fri, 16 Apr 2021 11:41:22 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 22B88610F7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=baylibre.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:Date:Message-ID:From: References:Cc:To:Subject:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=o22nYZ/3a/joNzGA7ChpRA6o5wB06akwnqZxUw+aSb4=; b=Bd+xQ+/TjdaOMGt6XDrAGu2z2 efNfmtH7gzEh+0sE+5K/YiWkCaArEXVFFqTMnFdBAAcWfvz1fFjlF6C75Km1SP98pxHBzmuqepI9E zpLA82PRkY48GCpeN2G4wucUYwX8NJy+w5O5YlXZsMQXINZLez5s7bGWWw0+zeDBwcmtGYnHhR2ah 6uttNJdAoGwjrWOKf2YlsRA+4vqbCGA52AtVyyZ02C1P2TV2YHNh6wV1XJhAkusj3x0IBYcxiNrHg eplVx6yxZ3mAd63NdvZKWRpmcdXlUf1ThO5FPFFR+dYyBpWwmmlErDS93OkA2+GMTTDDzuqr/JVjI MbrIjS36g==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1lXMou-001xAD-DW; Fri, 16 Apr 2021 11:39:35 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lXMoT-001x2V-2u for linux-arm-kernel@desiato.infradead.org; Fri, 16 Apr 2021 11:39:05 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:MIME-Version:Date:Message-ID:From:References:Cc:To: Subject:Sender:Reply-To:Content-ID:Content-Description; bh=Ch3B1QB839TpxbyTCaHh7+PjqFlJHeFp/HZU3MiGscw=; b=IAwjSCBzJycYOWf+zN8uAKs/Rt X/ryPthjcB+HdhVtYzJGOW4hBHJQM34UkDuIb6HKwe1PnYP7HFAmFFLtLCcKBjgFkcJrfzLdoxSjQ vyCvPCbyZn0+z68Thko8VnchyUAVkf1vfpGqJT086KZUeWwy29mDqQKPYNVwXVQJcHlEx6ilpyEFU xvdWwoSwrJlekiz/vweldj/uB913bctOknDhj+kCN4GWD4w28QS2n3huTcL520jrDAR3fFn0BbROG 1nlK59zFFGPiUHE83QCUBnbPUFAlZIo7ibHQc6EbD2iHb1qZUyxwpjEcJO3WjllVaBrceszGik4Jy 6oXjWHdg==; Received: from mail-wr1-x42b.google.com ([2a00:1450:4864:20::42b]) by bombadil.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1lXMoP-009K8c-TC for linux-arm-kernel@lists.infradead.org; Fri, 16 Apr 2021 11:39:03 +0000 Received: by mail-wr1-x42b.google.com with SMTP id m9so13624141wrx.3 for ; Fri, 16 Apr 2021 04:39:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=baylibre-com.20150623.gappssmtp.com; s=20150623; h=subject:to:cc:references:from:organization:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=Ch3B1QB839TpxbyTCaHh7+PjqFlJHeFp/HZU3MiGscw=; b=EkzQjer0WgUEgQkZ/WCQ1qZSR+xOL8CYkmgyGZqX8M/cpDnJ3Jdq7NAUhqBGqi3yjA RvxLBAhdzA+iPTcZCJ9eRsGEGviRSKwt63OrvHOCS0KWJWgntOZuiNpq0t2/LzV1v7RI XdY+G5TuRKGbvh/bK/vA+nuoL3oWvnx81/1QcUl0hPVXiX6lne0wZcU39Dnw01eexj4/ aAmRmD45JLqraflxN0P9n9NRW+tOLy31DVmNZNxB1sJtCQ6rBU4/vaMe3bZ/bjGdQU/c vNXcsAyBt2CKFWL7r7Dzm/htr5Q83g2zk0NzsSft44P0UdjSeRe0LKdJOehBAf0HNf2D 7mvQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:organization :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=Ch3B1QB839TpxbyTCaHh7+PjqFlJHeFp/HZU3MiGscw=; b=jeI2LqN9Eu5VyGLebTEA/bF9oMnUfe/TkvZZAfat4mDg0sKqa6WzpabdlAqmItl+a4 62NURN2Sz55z4wh/4JmuEWxW5D7TteG2ONRB9z7zvxxqsX0fc6MIH0sGPvOV49FpqtgG v5sw6pycg7sfHnHgNqJrdHBaIWg7Trg2yqkvqxJQw4iklkdB+WG/o6xREnZhdH/8HAZj oRtp8I4ByhSPVvzV7CT0jRvjb9DKJDKMwa178OH6nlGfpsizIEuNhGy9v7Ptlyc1EW6+ /5gPMVyB8aHpLsvz/xCkRdrAHvsnIyY4ui3Q0B2LzYYab7xvW2UFCCYdHsjydUfKEC7E 7Diw== X-Gm-Message-State: AOAM533zPT0ujJQNqX1+i8jG+XT7+xZGAo6MvoViFn5il3yKexvj3n02 NblJ9aaYzguz0XVNgKUhehvfDQ== X-Google-Smtp-Source: ABdhPJxV3W8/JmRRJjOYH3rbQ9IP5SnGF8wi+6Gmv+4bzOiXNfk7ypsXlDfWMH46OpTJMpcWlMSOlg== X-Received: by 2002:a5d:4d46:: with SMTP id a6mr8565355wru.3.1618573140641; Fri, 16 Apr 2021 04:39:00 -0700 (PDT) Received: from ?IPv6:2a01:e0a:90c:e290:6e70:fd4e:dfdb:68d7? ([2a01:e0a:90c:e290:6e70:fd4e:dfdb:68d7]) by smtp.gmail.com with ESMTPSA id n2sm9756992wmb.32.2021.04.16.04.38.59 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 16 Apr 2021 04:39:00 -0700 (PDT) Subject: Re: [PATCH 0/2] drm/bridge: dw-hdmi: disable loading of DW-HDMI CEC sub-driver To: Laurent Pinchart Cc: jonas@kwiboo.se, jernej.skrabec@siol.net, robert.foss@linaro.org, dri-devel@lists.freedesktop.org, linux-amlogic@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org References: <20210416092737.1971876-1-narmstrong@baylibre.com> From: Neil Armstrong Organization: Baylibre Message-ID: <96b9e144-0791-4c19-3e3c-b0e9efb86138@baylibre.com> Date: Fri, 16 Apr 2021 13:38:59 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: Content-Language: en-US X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210416_043902_040922_8219BF7F X-CRM114-Status: GOOD ( 23.88 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 16/04/2021 11:58, Laurent Pinchart wrote: > Hi Neil, > > On Fri, Apr 16, 2021 at 11:27:35AM +0200, Neil Armstrong wrote: >> This adds DW-HDMI driver a glue option to disable loading of the CEC sub-driver. >> >> On some SoCs, the CEC functionality is enabled in the IP config bits, but the >> CEC bus is non-functional like on Amlogic SoCs, where the CEC config bit is set >> but the DW-HDMI CEC signal is not connected to a physical pin, leading to some >> confusion when the DW-HDMI CEC controller can't communicate on the bus. > > If we can't trust the CEC config bit, would it be better to not use it > at all, and instead let each platform glue logic tell whether to enable > CEC or not ? Actually, the CEC config bit is right, the HW exists and should be functional, but this bit doesn't tell if the CEC signal is connected to something. This lies in the IP integration, like other bits under the "amlogic,meson-*-dw-hdmi" umbrella. The first attempt was by Hans using DT, but adding a property in DT for a vendor specific compatible doesn't make sense. Another idea would be to describe the CEC signal endpoint like we do for video signal, but I think this is out of scope and this solution is much simpler and straightforward, and it's more an exception than a general use case to solve. Neil > >> Jernej Skrabec (1): >> drm/bridge/synopsys: dw-hdmi: Add an option to suppress loading CEC >> driver >> >> Neil Armstrong (1): >> drm/meson: dw-hdmi: disable DW-HDMI CEC sub-driver >> >> drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 2 +- >> drivers/gpu/drm/meson/meson_dw_hdmi.c | 1 + >> include/drm/bridge/dw_hdmi.h | 2 ++ >> 3 files changed, 4 insertions(+), 1 deletion(-) >> > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel