From nobody Tue Apr 7 08:09:52 2026 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 CEEBDC4332F for ; Wed, 12 Oct 2022 16:29:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230111AbiJLQ3e (ORCPT ); Wed, 12 Oct 2022 12:29:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41096 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230077AbiJLQ3S (ORCPT ); Wed, 12 Oct 2022 12:29:18 -0400 Received: from mail-pg1-x534.google.com (mail-pg1-x534.google.com [IPv6:2607:f8b0:4864:20::534]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C2D49FBCDF for ; Wed, 12 Oct 2022 09:29:11 -0700 (PDT) Received: by mail-pg1-x534.google.com with SMTP id s206so15974995pgs.3 for ; Wed, 12 Oct 2022 09:29:11 -0700 (PDT) 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=cn1tYSp6Fs26zz8mdx6XxYmQlY8g3zLtpMK7g8RZT1U=; b=Fs4gWIc/2+USWqzntDJRD8yynnsb+1iJJm80wz2TexKT+yj1/30tVTpzfqpdS8pCvH HS4tBX00esP9gFzO0IfU6EgXKKLTonR/DMOrz79rWkAnGGazztmHzy3D0Pp9NhYjlbjx 8bPjoHnzoGMcOrDGW71iHil+DqNvPV6tnom7I= 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=cn1tYSp6Fs26zz8mdx6XxYmQlY8g3zLtpMK7g8RZT1U=; b=pl67gVhL4yhBI2LXUJvC20SYIYjNJQwsXzn0Gul7srA/XIEopaqGHZLAFbQW64JfuI QNVclPPTcihtvSNz7pYLmZqHLCuojorTGGDqiHkKRkPIPAHGTQRE+oco5coh74E7ks3l e/nuPnfeIyg0W0ySl1Pl7OT5PGCX2iMv8CTMQR/Hiw6TLcXRFMeC2JmGHLfjgFs48UJR Q/CLnLA7vghXCr/yo2rZAbrbI0r6Uba51C5A+FFMKzl5g57Apo0XOu4LuEBda+SSF1Fh xiNkGPUb4xj9EObGHnmHQQ6R+eiQ5wB7qaClQZOa/YJ9ewEj0U09BomaMnzH4oSKnkt7 34GQ== X-Gm-Message-State: ACrzQf3cstGm5B+MPc6V6kLhbb0+FMOQ0MiFcY9chwQvKUlZUf3EINms Gy+M+4D+7fXNf7lEH/Is36izrg== X-Google-Smtp-Source: AMsMyM6HxJ+lgT8f8WrnaKCblNjlb/TUbZ2wY3dcWmlOhT8Hmm5Z6eImkf02dCMv+Hli0GCNG87qgA== X-Received: by 2002:a05:6a00:8cc:b0:52c:7ab5:2ce7 with SMTP id s12-20020a056a0008cc00b0052c7ab52ce7mr31258809pfu.28.1665592150442; Wed, 12 Oct 2022 09:29:10 -0700 (PDT) Received: from treapking.tpe.corp.google.com ([2401:fa00:1:10:2921:f6a9:5848:18e1]) by smtp.gmail.com with ESMTPSA id l4-20020a635704000000b0045dc85c4a5fsm9722163pgb.44.2022.10.12.09.29.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 12 Oct 2022 09:29:09 -0700 (PDT) From: Pin-yen Lin To: Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , David Airlie , Daniel Vetter Cc: Pin-yen Lin , Allen Chen , AngeloGioacchino Del Regno , Hermes Wu , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/3] drm/bridge: it6505: Initialize AUX channel in it6505_i2c_probe Date: Thu, 13 Oct 2022 00:28:57 +0800 Message-Id: <20221012162900.2876686-2-treapking@chromium.org> X-Mailer: git-send-email 2.38.0.rc1.362.ged0d419d3c-goog In-Reply-To: <20221012162900.2876686-1-treapking@chromium.org> References: <20221012162900.2876686-1-treapking@chromium.org> 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" During device boot, the HPD interrupt could be triggered before the DRM subsystem registers it6505 as a DRM bridge. In such cases, the driver tries to access AUX channel and causes NULL pointer dereference. Initializing the AUX channel earlier to prevent such error. Fixes: b5c84a9edcd4 ("drm/bridge: add it6505 driver") Signed-off-by: Pin-yen Lin --- drivers/gpu/drm/bridge/ite-it6505.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/i= te-it6505.c index a4302492cf8d..f7f6c3e20fae 100644 --- a/drivers/gpu/drm/bridge/ite-it6505.c +++ b/drivers/gpu/drm/bridge/ite-it6505.c @@ -2871,10 +2871,7 @@ static int it6505_bridge_attach(struct drm_bridge *b= ridge, } =20 /* Register aux channel */ - it6505->aux.name =3D "DP-AUX"; - it6505->aux.dev =3D dev; it6505->aux.drm_dev =3D bridge->dev; - it6505->aux.transfer =3D it6505_aux_transfer; =20 ret =3D drm_dp_aux_register(&it6505->aux); =20 @@ -3354,6 +3351,11 @@ static int it6505_i2c_probe(struct i2c_client *clien= t, debugfs_init(it6505); pm_runtime_enable(dev); =20 + it6505->aux.name =3D "DP-AUX"; + it6505->aux.dev =3D dev; + it6505->aux.transfer =3D it6505_aux_transfer; + drm_dp_aux_init(&it6505->aux); + it6505->bridge.funcs =3D &it6505_bridge_funcs; it6505->bridge.type =3D DRM_MODE_CONNECTOR_DisplayPort; it6505->bridge.ops =3D DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID | --=20 2.38.0.rc1.362.ged0d419d3c-goog