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=-8.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 80EFBC433DB for ; Tue, 23 Mar 2021 07:25:45 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 3CF5D619AB for ; Tue, 23 Mar 2021 07:25:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 3CF5D619AB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id B08636E84C; Tue, 23 Mar 2021 07:25:44 +0000 (UTC) Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by gabe.freedesktop.org (Postfix) with ESMTPS id 293366E84C for ; Tue, 23 Mar 2021 07:25:43 +0000 (UTC) Received: by mail-pj1-x102a.google.com with SMTP id j6-20020a17090adc86b02900cbfe6f2c96so9748971pjv.1 for ; Tue, 23 Mar 2021 00:25:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=mime-version:content-transfer-encoding:in-reply-to:references :subject:from:cc:to:date:message-id:user-agent; bh=UKDB4tP1o/qAJ5iZQYJec7JsyNelKTQdItmX1ycjyQk=; b=ZETG82JILVxDJCi3qiI1q0/LQNcWe9kN64W1uB852/RlDMI5Yh6PhOnBgKohVs1Xhq b2j43WJ1y0Gj/KQt3KYF3WXHWu9xefZzPtfdm40QocAiaK4lE24hDSjYV219L8YJWjol dupj1bUlLOxCnPRBRReCjJHZS8pgOjJ51nnXI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:content-transfer-encoding :in-reply-to:references:subject:from:cc:to:date:message-id :user-agent; bh=UKDB4tP1o/qAJ5iZQYJec7JsyNelKTQdItmX1ycjyQk=; b=liuzgWDn/4eEo6HGgtJ9jWWL4uz4xEUsifBvlijUx4/4abSKOu/Q4oRPk2DMY2cU3t 1ghon6+CWUF35Cjt0ILFZhuk9/1MI2nxHPb5xINidhwxdiaakt83cZXj6Jw8XUsEYJHi 3orfHLRPogMzROQq9QJHsQfrBHRzs5wxLxff9e6Ka633HGyU59qeM0H/SdoTjFlOsZ7J 9/6Bb6FnTCbEdBOH1zn3PuI+sJdCLJ+Hxk/Dk7UuGgUaZowiABmYM746wfFIuIUo5G69 2SpYkBj+/+fq0PbeJxMbg5lRMQTeAffVZEJOGGIf7tR98ZoIGVbOZEIr1CoHLA4oRNHj D+DA== X-Gm-Message-State: AOAM533w+SFXJJiIAKiG619roilfEos9K9xdsoNVfoSgJ2UxmF7tSBqI gQyVaJOzhzdoTba3PbafHK/k0g== X-Google-Smtp-Source: ABdhPJyPgeACfzPrxFvaTFzN2uVCCvcZfR0JEVYNsM780SwaiY1fnBGhInJl6nD7HjGAyflWidV26A== X-Received: by 2002:a17:90a:c902:: with SMTP id v2mr3287152pjt.144.1616484342636; Tue, 23 Mar 2021 00:25:42 -0700 (PDT) Received: from chromium.org ([2620:15c:202:201:e90d:d453:87ae:2e10]) by smtp.gmail.com with ESMTPSA id z1sm15806362pfn.127.2021.03.23.00.25.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Mar 2021 00:25:41 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <20201030011738.2028313-1-swboyd@chromium.org> <20201101173741.GA1293305@ravnborg.org> <160436612483.884498.883110130131457033@swboyd.mtv.corp.google.com> Subject: Re: [PATCH v2 0/4] drm/bridge: ti-sn65dsi86: Support EDID reading From: Stephen Boyd To: Laurent Pinchart Date: Tue, 23 Mar 2021 00:25:40 -0700 Message-ID: <161648434035.3012082.16414745959476755420@swboyd.mtv.corp.google.com> User-Agent: alot/0.9.1 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jernej Skrabec , Jonas Karlman , Neil Armstrong , linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, Douglas Anderson , Andrzej Hajda , Sean Paul , Sam Ravnborg Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Quoting Laurent Pinchart (2021-03-22 17:00:23) > Hi Stephen, > > On Mon, Nov 02, 2020 at 05:15:24PM -0800, Stephen Boyd wrote: > > Quoting Sam Ravnborg (2020-11-01 09:37:41) > > > Hi Stephen. > > > > > > On Thu, Oct 29, 2020 at 06:17:34PM -0700, Stephen Boyd wrote: > > > > This patch series cleans up the DDC code a little bit so that > > > > it is more efficient time wise and supports grabbing the EDID > > > > of the eDP panel over the aux channel. I timed this on a board > > > > I have on my desk and it takes about 20ms to grab the EDID out > > > > of the panel and make sure it is valid. > > > > > > > > The first two patches seem less controversial so I stuck them at > > > > the beginning. The third patch does the EDID reading and caches > > > > it so we don't have to keep grabbing it over and over again. And > > > > finally the last patch updates the reply field so that short > > > > reads and nacks over the channel are reflected properly instead of > > > > treating them as some sort of error that can't be discerned. > > > > > > > > Stephen Boyd (4): > > > > drm/bridge: ti-sn65dsi86: Combine register accesses in > > > > ti_sn_aux_transfer() > > > > drm/bridge: ti-sn65dsi86: Make polling a busy loop > > > > drm/bridge: ti-sn65dsi86: Read EDID blob over DDC > > > > drm/bridge: ti-sn65dsi86: Update reply on aux failures > > > > > > Series looks good. You can add my a-b on the full series. > > > Acked-by: Sam Ravnborg > > > > > > I can apply after Douglas have had a look at the patches he did not r-b > > > yet. > > > > > > Any chance we can convince you to prepare this bridge driver for use in > > > a chained bridge setup where the connector is created by the display > > > driver and uses drm_bridge_funcs? > > > > > > First step wuld be to introduce the use of a panel_bridge. > > > Then add get_edid to drm_bridge_funcs and maybe more helpers. > > > > > > Then natural final step would be to move connector creation to the > > > display driver - see how other uses drm_bridge_connector_init() to do so > > > - it is relatively simple. > > > > > > Should be doable - and reach out if you need some help. > > > > I started to look at this and got stuck at ti_sn_bridge_get_bpp(). Where > > can I get the details of the bpc for the downstream bridge or panel? Is > > there some function that can tell this bridge what the bpc is for the > > attached connector? > > I've posted a patch series to convert to DRM_BRIDGE_ATTACH_NO_CONNECTOR > yesterday (and have CC'ed you), but I've overlooked this particular > problem :-S ! > > You can't get the connector in the .enable() operation, but you can get > it in .atomic_enable(), with > drm_atomic_get_new_connector_for_encoder(). This being said, it's > probably not the right option. > > What matters here isn't the bpc for the connector, but the format > expected by the next bridge in the chain. drm_bridge_funcs has two > operations, .atomic_get_output_bus_fmts() and > .atomic_get_input_bus_fmts(), to negotiate that format along a chain of > bridges. The panel bridge driver (drivers/gpu/drm/bridge/panel.c) > doesn't implement those operations, and neither does > display-connector.c, so that may be what we should start with. Ok, makes sense. I'd gladly test things out if you come up with some solution here. _______________________________________________ dri-devel mailing list dri-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/dri-devel