From nobody Sat Apr 27 01:55:57 2024 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 142C3C433F5 for ; Fri, 13 May 2022 20:15:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1384000AbiEMUPg (ORCPT ); Fri, 13 May 2022 16:15:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58786 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1357601AbiEMUPe (ORCPT ); Fri, 13 May 2022 16:15:34 -0400 Received: from mail-qv1-xf34.google.com (mail-qv1-xf34.google.com [IPv6:2607:f8b0:4864:20::f34]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 55EF93B576 for ; Fri, 13 May 2022 13:15:33 -0700 (PDT) Received: by mail-qv1-xf34.google.com with SMTP id c8so7554181qvh.10 for ; Fri, 13 May 2022 13:15:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=z8tyfGIyj4QCjWxzXzO8gJFUZd4JNIC7ZKxyO4yxAcs=; b=F1DwqMbX3C4qM5XgU+UfmsdneLS0XU7rLeNYlh9QwnShg4eBHYTmLougzM4093Zgq3 LeVMSUKpnmOp1po+rlLKyEBMh1uhHNo0MYtEYk6jOB8JwVpzjwio/D3C4D745ZFM8i+a hFZ8UKOQKjO+iEj6taXWN4v3Cv+4Jb2LTbD+0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=z8tyfGIyj4QCjWxzXzO8gJFUZd4JNIC7ZKxyO4yxAcs=; b=st5Tkkncl3Ud8WADI4Eq+sp5gDIh31l3FZjo+thdyOv6IRuz5ujICNgw5yQ05v17zE 6DtCu6KzzDyR4EGs5hewdWOPPLqKgCbUajRYCFOR9d49DCDAW/TkQUP5TQ19/0WAYprD AqlTzkm3uwKGovBbaNPF1ED95nM++HAwVkjvq/NB/o8X3rS8gbLE3yrOK10YoR7okMnt PhS8z+RhkigSqYV/UtFlHprzlzbrIbKeBW3psqMs/iLyRgjberQTzIEzfawWUgZXj+Cp arnGdt5n+s/NtDHJV4r40e+BObJg0o7srb3Mg2srguq3cvUfjHfUk6YH6XiaJDdojZCV aduQ== X-Gm-Message-State: AOAM531rkjscFd4mnR/OC6QkgzOJmZ+SUW4Vo3V7SVFKyQh4yy8hnNgf xcG2uktENC0/NMb9aa3DziRxaIijSt/E1MX7pKrK6w== X-Google-Smtp-Source: ABdhPJzcImkmUNnAnRYKJR4fAAj/PKirufEjVgtKSVv9x3OVOt1fZUvIBWdxj8liHAinYjSiebfazA== X-Received: by 2002:a17:902:a981:b0:156:229d:6834 with SMTP id bh1-20020a170902a98100b00156229d6834mr5874937plb.128.1652472921993; Fri, 13 May 2022 13:15:21 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:201:f334:6f80:82ed:5653]) by smtp.gmail.com with ESMTPSA id im2-20020a170902bb0200b0015e8d4eb1bdsm2332362plb.7.2022.05.13.13.15.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 13 May 2022 13:15:21 -0700 (PDT) From: Douglas Anderson To: Rob Clark , Abhinav Kumar , Dmitry Baryshkov Cc: Dave Stevenson , Douglas Anderson , Bjorn Andersson , Daniel Vetter , David Airlie , Sean Paul , Stephen Boyd , Vinod Koul , dri-devel@lists.freedesktop.org, freedreno@lists.freedesktop.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v5] drm/msm/dsi: don't powerup at modeset time for parade-ps8640 Date: Fri, 13 May 2022 13:15:13 -0700 Message-Id: <20220513131504.v5.1.Ia196e35ad985059e77b038a41662faae9e26f411@changeid> X-Mailer: git-send-email 2.36.0.550.gb090851708-goog MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Commit 7d8e9a90509f ("drm/msm/dsi: move DSI host powerup to modeset time") caused sc7180 Chromebooks that use the parade-ps8640 bridge chip to fail to turn the display back on after it turns off. Unfortunately, it doesn't look easy to fix the parade-ps8640 driver to handle the new power sequence. The Linux driver has almost nothing in it and most of the logic for this bridge chip is in black-box firmware that the bridge chip uses. Also unfortunately, reverting the patch will break "tc358762". The long term solution here is probably Dave Stevenson's series [1] that would give more flexibility. However, that is likely not a quick fix. For the short term, we'll look at the compatible of the next bridge in the chain and go back to the old way for the Parade PS8640 bridge chip. If it's found that other bridge chips also need this workaround then we can add them to the list or consider inverting the condition. However, the hope is that the framework will not take too much longer to land and we won't have to add anything other than ps8640 here. [1] https://lore.kernel.org/r/cover.1646406653.git.dave.stevenson@raspberry= pi.com Fixes: 7d8e9a90509f ("drm/msm/dsi: move DSI host powerup to modeset time") Suggested-by: Rob Clark Signed-off-by: Douglas Anderson Reviewed-by: Dmitry Baryshkov Reviewed-by: Abhinav Kumar --- Note that, unlike `struct device`, `struct drm_bridge` still has a `#ifdef` around the `of_node`. The extra stub function in this patch is to make sure that we can pass COMPILE_TEST, not because I expect that we'll actually run into real users who are running this driver without device tree. Changes in v5: - Add a comment saying that this is temporary. Changes in v4: - Use the compatible string of the next bridge as per Rob. Changes in v3: - No longer a revert; now a module parameter. Changes in v2: - Remove the mud from my face. drivers/gpu/drm/msm/dsi/dsi_manager.c | 32 ++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c b/drivers/gpu/drm/msm/ds= i/dsi_manager.c index 50b987658b1f..7fe5eb1dd066 100644 --- a/drivers/gpu/drm/msm/dsi/dsi_manager.c +++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c @@ -34,6 +34,32 @@ static struct msm_dsi_manager msm_dsim_glb; #define IS_SYNC_NEEDED() (msm_dsim_glb.is_sync_needed) #define IS_MASTER_DSI_LINK(id) (msm_dsim_glb.master_dsi_link_id =3D=3D id) =20 +#ifdef CONFIG_OF +static bool dsi_mgr_power_on_early(struct drm_bridge *bridge) +{ + struct drm_bridge *next_bridge =3D drm_bridge_get_next_bridge(bridge); + + /* + * If the next bridge in the chain is the Parade ps8640 bridge chip + * then don't power on early since it seems to violate the expectations + * of the firmware that the bridge chip is running. + * + * NOTE: this is expected to be a temporary special case. It's expected + * that we'll eventually have a framework that allows the next level + * bridge to indicate whether it needs us to power on before it or + * after it. When that framework is in place then we'll use it and + * remove this special case. + */ + return !(next_bridge && next_bridge->of_node && + of_device_is_compatible(next_bridge->of_node, "parade,ps8640")); +} +#else +static inline bool dsi_mgr_power_on_early(struct drm_bridge *bridge) +{ + return true; +} +#endif + static inline struct msm_dsi *dsi_mgr_get_dsi(int id) { return msm_dsim_glb.dsi[id]; @@ -389,6 +415,9 @@ static void dsi_mgr_bridge_pre_enable(struct drm_bridge= *bridge) if (is_bonded_dsi && !IS_MASTER_DSI_LINK(id)) return; =20 + if (!dsi_mgr_power_on_early(bridge)) + dsi_mgr_bridge_power_on(bridge); + /* Always call panel functions once, because even for dual panels, * there is only one drm_panel instance. */ @@ -570,7 +599,8 @@ static void dsi_mgr_bridge_mode_set(struct drm_bridge *= bridge, if (is_bonded_dsi && other_dsi) msm_dsi_host_set_display_mode(other_dsi->host, adjusted_mode); =20 - dsi_mgr_bridge_power_on(bridge); + if (dsi_mgr_power_on_early(bridge)) + dsi_mgr_bridge_power_on(bridge); } =20 static enum drm_mode_status dsi_mgr_bridge_mode_valid(struct drm_bridge *b= ridge, --=20 2.36.0.550.gb090851708-goog