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=-8.8 required=3.0 tests=BAYES_00, 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 B1DE7C64E7B for ; Sun, 29 Nov 2020 22:12:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E0D32222A for ; Sun, 29 Nov 2020 22:12:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728287AbgK2WMr (ORCPT ); Sun, 29 Nov 2020 17:12:47 -0500 Received: from asavdk3.altibox.net ([109.247.116.14]:41382 "EHLO asavdk3.altibox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725950AbgK2WMq (ORCPT ); Sun, 29 Nov 2020 17:12:46 -0500 Received: from ravnborg.org (unknown [188.228.123.71]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by asavdk3.altibox.net (Postfix) with ESMTPS id A968320031; Sun, 29 Nov 2020 23:11:59 +0100 (CET) Date: Sun, 29 Nov 2020 23:11:58 +0100 From: Sam Ravnborg To: Douglas Anderson Cc: Thierry Reding , robdclark@chromium.org, David Airlie , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Rob Herring Subject: Re: [PATCH v4 3/5] drm: panel: simple: Allow specifying the delay from prepare to enable Message-ID: <20201129221158.GJ1162850@ravnborg.org> References: <20201109170018.v4.1.Icaa86f0a4ca45a9a7184da4bc63386b29792d613@changeid> <20201109170018.v4.3.Ib9ce3c6482f464bf594161581521ced46bbd54ed@changeid> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201109170018.v4.3.Ib9ce3c6482f464bf594161581521ced46bbd54ed@changeid> X-CMAE-Score: 0 X-CMAE-Analysis: v=2.3 cv=Ibmpp1ia c=1 sm=1 tr=0 a=S6zTFyMACwkrwXSdXUNehg==:117 a=S6zTFyMACwkrwXSdXUNehg==:17 a=kj9zAlcOel0A:10 a=cm27Pg_UAAAA:8 a=4Av5kLI2NlvhjzHu5tUA:9 a=CjuIK1q_8ugA:10 a=xmb-EsYY8bH0VWELuYED:22 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Douglas, On Mon, Nov 09, 2020 at 05:00:57PM -0800, Douglas Anderson wrote: > On the panel I'm looking at, there's an 80 ms minimum time between HPD > being asserted by the panel and setting the backlight enable GPIO. > While we could just add an 80 ms "enable" delay, this is not ideal. > Link training is allowed to happen in parallel with this delay so the > fixed 80 ms delay over-delays. > > We'll support this by logging the time at the end of prepare and then > delaying in enable if enough time hasn't passed. > > Signed-off-by: Douglas Anderson Applied too. Sam