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=-1.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED 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 AB15FC04AB4 for ; Fri, 17 May 2019 08:15:22 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 77D9920848 for ; Fri, 17 May 2019 08:15:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="CKi5hzO8" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 77D9920848 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-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=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=y1kmJMJT5pe/3V68E7ABcAucPvsEVwzoAut8U5gfAgs=; b=CKi5hzO8j7zLO+ 1RcJwOqo+LHMclFOD6aVWBjn/fD0fUQPyJfbthqxrqgbTGSfULCKGHW0ULzLGVJBAVHDFBH2YHVqH PNSs9UyNUHNTOlHsh6eyJb8jTGkFIWjZRCRXQ75wCfeNTEB5flXj0t8MwUUd8atQZzujD3yLABZmf 3Q5bFeuulnGxFoccxHaplcH9Nuqpu6dkmW8q2UoHex7ENnzXsZKcJcNeGm4uTKlWs6nFxNI7VgFA5 0PQ6z3oazEEzxXQArjY4MPo8UWhNRxULfoZJtKfxYCEQAzEaE6ktchhY2R7CwjuAwecuaBfHES7VR mtrQByGNvxkU/4L3bO/Q==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hRY1L-0005cw-RJ; Fri, 17 May 2019 08:15:15 +0000 Received: from verein.lst.de ([213.95.11.211] helo=newverein.lst.de) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hRY1H-0005cP-Tr for linux-arm-kernel@lists.infradead.org; Fri, 17 May 2019 08:15:13 +0000 Received: by newverein.lst.de (Postfix, from userid 107) id 97CF968B20; Fri, 17 May 2019 10:14:49 +0200 (CEST) Received: from blackhole.lan (p5B33F92B.dip0.t-ipconnect.de [91.51.249.43]) by newverein.lst.de (Postfix) with ESMTPSA id DBFF067329; Fri, 17 May 2019 10:14:19 +0200 (CEST) Date: Fri, 17 May 2019 10:14:18 +0200 From: Torsten Duwe To: Maxime Ripard Subject: Re: [PATCH 4/4] arm64: DTS: allwinner: a64: enable ANX6345 bridge on Teres-I Message-ID: <20190517101353.3e86d696@blackhole.lan> In-Reply-To: <20190517072738.deohh5fly4jxms7k@flea> References: <20190514155911.6C0AC68B05@newverein.lst.de> <20190514160241.9EAC768C7B@newverein.lst.de> <20190515093141.41016b11@blackhole.lan> <20190516154820.GA10431@lst.de> <20190516164859.GB10431@lst.de> <20190517072738.deohh5fly4jxms7k@flea> Organization: LST e.V. X-Mailer: Claws Mail 3.16.0 (GTK+ 2.24.32; x86_64-suse-linux-gnu) MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190517_011512_113543_43EB5F48 X-CRM114-Status: GOOD ( 17.42 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , devicetree , David Airlie , linux-kernel , dri-devel , Andrzej Hajda , Chen-Yu Tsai , Rob Herring , Thierry Reding , Laurent Pinchart , Daniel Vetter , Harald Geyer , Sean Paul , arm-linux , Icenowy Zheng Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Fri, 17 May 2019 09:27:38 +0200 Maxime Ripard wrote: > On Thu, May 16, 2019 at 06:48:59PM +0200, Torsten Duwe wrote: > > On Thu, May 16, 2019 at 09:06:41AM -0700, Vasily Khoruzhick wrote: > > > > > > Driver can talk to the panel over AUX channel only after t1+t3, > > > t1 is up to 10ms, t3 is up to 200ms. > > > > This is after power-on. The boot loader needs to deal with this. > > The bootloader can deal with it, but the kernel will also need to. The > bootloader might not be doing this because it's not been updated, the > regulator might have been disabled between the time the kernel was > started and the time the bridge driver probes, etc. No, you cannot practically switch off this voltage. It supports _all_ the devices I mentioned. In fact, the PMIC needs to enable it initially, and then it takes some time before the SoC can access the MMC and read the SPL from it, just because of exactly these 3.3V. Then the boot loader starts, and later the eDP bridge gets initialised. In *theory*, albeit a very daring one, I could imagine a very deep sleep mode that can only be ended by pressing the power button, which should still work without DCDC1. Only then, a description of the panel would be required. But I probably missed something and even this does not work. So for all current practical purposes, we can assume the Teres-I panel to be powered properly and providing valid EDID; nothing to worry about in software. HTH, Torsten _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel