From patchwork Thu Dec 8 19:20:03 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 13068694 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DE751C10F1E for ; Thu, 8 Dec 2022 19:20:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229737AbiLHTUg (ORCPT ); Thu, 8 Dec 2022 14:20:36 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45294 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229704AbiLHTUf (ORCPT ); Thu, 8 Dec 2022 14:20:35 -0500 Received: from mail-pj1-x1034.google.com (mail-pj1-x1034.google.com [IPv6:2607:f8b0:4864:20::1034]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 11D289951A for ; Thu, 8 Dec 2022 11:20:34 -0800 (PST) Received: by mail-pj1-x1034.google.com with SMTP id q17-20020a17090aa01100b002194cba32e9so5691405pjp.1 for ; Thu, 08 Dec 2022 11:20:34 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=RXZFKzf8SEbO5MJF/tbRe/Hy6ddvI0OXNJGHZyfmauA=; b=RtJ6gvU4u20lqWyhOPFyXMpF2NNgS93C/PcBqKyQgBoFU/M+fleiQZVu+iLC5JcJ7M k1BnmfKE+l26w6sOkxNlZblsmHXxnqW6B51hWf7K1Fx8xpIAta67G1itL2XTPNVkTqMF rTDYvm+ygXrkJIXQrKCfRD4GXpt6a3f9bTeSc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=RXZFKzf8SEbO5MJF/tbRe/Hy6ddvI0OXNJGHZyfmauA=; b=5mJ7bW+Ol5UCx3VT/svQtE5BkxkWgJZeYNn9Qnv7IlQpKxCfAJb/s2a77HK5MAd/Rp m/kYXN3KHEnouDy3etXUIXOHMchX2KRp3lfNFUsjN13UGqAaehNVFkKScr25Wcza4bXz g5WruCqmDXYX5+QCsbZhUTbArhcok3ue+SiSZQBh16uVvhM7KAExSNG11GXeQvc+08df yusqGNO0vwQllWlrvQ7syiQ8Q9ZjL325OZldXT/xS9BA4M+D2T134lHNw2qLZgKrC3B3 83UERpaf2J09P9FQK3sSAtPI0p22Ctr+1NIL26TLzmlGW+Y02j7A6Az+qwO6Ruz66BBl XvPw== X-Gm-Message-State: ANoB5pmgUHnTnoq/gWkhlOWxlhScQ1EvQRDPBsmrt6wYUdLx05CZuaXn KZczes4m80WVzSmEdM9am209Hw== X-Google-Smtp-Source: AA0mqf6oAueA5N3ojF9g2UU8lo98Akl0XQg6efVKCgb/OgaGdyGx3oRASvhK8156nzOWVHnnI212Nw== X-Received: by 2002:a17:902:ab57:b0:189:4de5:6c7f with SMTP id ij23-20020a170902ab5700b001894de56c7fmr2866574plb.3.1670527233568; Thu, 08 Dec 2022 11:20:33 -0800 (PST) Received: from tictac2.mtv.corp.google.com ([2620:15c:9d:2:3aa1:2c62:9ac:4468]) by smtp.gmail.com with ESMTPSA id u5-20020a170902e5c500b00186a2274382sm17112019plf.76.2022.12.08.11.20.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 08 Dec 2022 11:20:33 -0800 (PST) From: Douglas Anderson To: Bjorn Andersson , Dmitry Torokhov Cc: mka@chromium.org, swboyd@chromium.org, linux-arm-msm@vger.kernel.org, linux-input@vger.kernel.org, Yunlong Jia , Konrad Dybcio , Douglas Anderson , Andy Gross , Krzysztof Kozlowski , Rob Herring , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 2/5] arm64: dts: qcom: sc7180: Add trogdor eDP/touchscreen regulator off-on-time Date: Thu, 8 Dec 2022 11:20:03 -0800 Message-Id: <20221208111910.2.I65ac577411b017eff50e7a4fda254e5583ccdc48@changeid> X-Mailer: git-send-email 2.39.0.rc1.256.g54fd8350bd-goog In-Reply-To: <20221208192006.1070898-1-dianders@chromium.org> References: <20221208192006.1070898-1-dianders@chromium.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org In general, the timing diagrams for components specify a minimum time for power cycling the component. When we remove power from a device we need to let the device fully discharge and get to a quiescent state before applying power again. If we power a device on too soon then it might not have fully powered off and might be in a weird in-between / invalid state. eDP panels typically have a time that's at least 500 ms here. You can see that in Linux's panel-edp driver that nearly every device specifies a "unprepare" time of at least 500 ms. This is a common minimum and the 500 ms is even in the example in the eDP spec. In Linux, the "panel-edp" driver enforces this delay for its own control of the regulator, but the "panel-edp" driver can't do anything about other control of the regulator (for instance, by the touchpanel driver). Let's add 500 ms as a board constraint for the regulator that's used for eDP/touchpanel on trogdor boards. If a given trogdor board stuffs only panels that can use a shorter time or stuff some panels that need a larger time then they can manually adjust this timing. We'll only do this minimum delay for trogdor devices with eDP (ones that use either bridge chip), not for devices with MIPI panels. MIPI panels could have similar constraints but the 500 ms isn't necessarily as standard and there are no known cases where this delay is needed. For most trogdor boards, this doesn't actually seem to affect anything when testing against shipping Linux. However, with pazqel360 it seems that this does make a difference. It seems that the touchscreen on this board _also_ needs some time for the regulator to discharge. That time is much less than 500 ms, so we'll just put the eDP panel 500 ms in there since the board constraint should be the "max" of the components. Signed-off-by: Douglas Anderson Reviewed-by: Matthias Kaehlcke --- .../boot/dts/qcom/sc7180-trogdor-parade-ps8640.dtsi | 12 ++++++++++++ .../boot/dts/qcom/sc7180-trogdor-ti-sn65dsi86.dtsi | 12 ++++++++++++ 2 files changed, 24 insertions(+) diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor-parade-ps8640.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor-parade-ps8640.dtsi index ebd6765e2afa..e27a769f8cd4 100644 --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor-parade-ps8640.dtsi +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor-parade-ps8640.dtsi @@ -26,6 +26,18 @@ pp3300_brij_ps8640: pp3300-brij-ps8640-regulator { }; }; +/* + * ADDITIONS TO FIXED REGULATORS DEFINED IN PARENT DEVICE TREE FILES + * + * Sort order matches the order in the parent files (parents before children). + */ + +&pp3300_dx_edp { + off-on-delay-us = <500000>; +}; + +/* ADDITIONS TO NODES DEFINED IN PARENT DEVICE TREE FILES */ + &dsi0_out { remote-endpoint = <&ps8640_in>; }; diff --git a/arch/arm64/boot/dts/qcom/sc7180-trogdor-ti-sn65dsi86.dtsi b/arch/arm64/boot/dts/qcom/sc7180-trogdor-ti-sn65dsi86.dtsi index 65333709e529..3188788306d0 100644 --- a/arch/arm64/boot/dts/qcom/sc7180-trogdor-ti-sn65dsi86.dtsi +++ b/arch/arm64/boot/dts/qcom/sc7180-trogdor-ti-sn65dsi86.dtsi @@ -7,6 +7,18 @@ #include +/* + * ADDITIONS TO FIXED REGULATORS DEFINED IN PARENT DEVICE TREE FILES + * + * Sort order matches the order in the parent files (parents before children). + */ + +&pp3300_dx_edp { + off-on-delay-us = <500000>; +}; + +/* ADDITIONS TO NODES DEFINED IN PARENT DEVICE TREE FILES */ + &dsi0_out { remote-endpoint = <&sn65dsi86_in>; };