From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 059B125228D; Thu, 15 Jan 2026 16:52:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768495941; cv=none; b=QcN8AqAj99PCVvl317Zs5nuDq37lO16ZT/+odHuUHjzwj9e6fgS/NX+EZ/c+UkDzH7wvk2/fy/kdW/dkli1zP0XoEQIte8yrMt3b1Yjz6mizsLmjaKKC8hvyg5aMrIgoYb7eeAGvqDZcnAKBBiF3qbhZhaM84NSZJ/RytX2Dxv8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1768495941; c=relaxed/simple; bh=qdVWp603Ql5LubXRSiscej5NbPj4mq/QGNV2+VRBmJQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=l3jwwR7q9J4aQWRaP3L8xrNcFhFt7onskkeE2I8fsGge+gk+3r+LPK4rNyTf85ghlZ5B8Z+URXdXb21kDDRG1TpWtGhGDK63S00bFcbPO1UPPIVN8oqRv0Bao0OujUXhFu+SoDzZCb6deepLhFjUUw5ceqQTTlwTtGBdM24wqBk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jrHoI9Gd; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="jrHoI9Gd" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D06FC116D0; Thu, 15 Jan 2026 16:52:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1768495940; bh=qdVWp603Ql5LubXRSiscej5NbPj4mq/QGNV2+VRBmJQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=jrHoI9GdKSw3G0pHOPjuGuIXxOTbqGjDoMpaWCMQJZComwWDFdV4vY1jjD/0Zfaag 1fojQm/P7NkUIL3fRj5paiU8SA/RUeXtqKv+skGlu/WB3gMy7VeZjWp8RqQ7FrtYj9 Vy/UD/CsMTE1r3WOQoOm+rmMtktvUixqUUNsTnoE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Tomi Valkeinen , Aradhya Bhatia , Maxime Ripard , Linus Walleij Subject: [PATCH 6.18 021/181] Revert "drm/atomic-helper: Re-order bridge chain pre-enable and post-disable" Date: Thu, 15 Jan 2026 17:45:58 +0100 Message-ID: <20260115164203.090438338@linuxfoundation.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20260115164202.305475649@linuxfoundation.org> References: <20260115164202.305475649@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Tomi Valkeinen commit c1ef9a6cabb34dbc09e31417b0c0a672fe0de13a upstream. This reverts commit c9b1150a68d9362a0827609fc0dc1664c0d8bfe1. Changing the enable/disable sequence has caused regressions on multiple platforms: R-Car, MCDE, Rockchip. A series (see link below) was sent to fix these, but it was decided that it's better to revert the original patch and change the enable/disable sequence only in the tidss driver. Reverting this commit breaks tidss's DSI and OLDI outputs, which will be fixed in the following commits. Signed-off-by: Tomi Valkeinen Link: https://lore.kernel.org/all/20251202-mcde-drm-regression-thirdfix-v6-0-f1bffd4ec0fa%40kernel.org/ Fixes: c9b1150a68d9 ("drm/atomic-helper: Re-order bridge chain pre-enable and post-disable") Cc: stable@vger.kernel.org # v6.17+ Reviewed-by: Aradhya Bhatia Reviewed-by: Maxime Ripard Reviewed-by: Linus Walleij Tested-by: Linus Walleij Signed-off-by: Linus Walleij Link: https://patch.msgid.link/20251205-drm-seq-fix-v1-1-fda68fa1b3de@ideasonboard.com Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/drm_atomic_helper.c | 8 +- include/drm/drm_bridge.h | 249 ++++++++-------------------- 2 files changed, 70 insertions(+), 187 deletions(-) diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c index 10adac9397cf..ef97f37560b2 100644 --- a/drivers/gpu/drm/drm_atomic_helper.c +++ b/drivers/gpu/drm/drm_atomic_helper.c @@ -1341,9 +1341,9 @@ disable_outputs(struct drm_device *dev, struct drm_atomic_state *state) { encoder_bridge_disable(dev, state); - crtc_disable(dev, state); - encoder_bridge_post_disable(dev, state); + + crtc_disable(dev, state); } /** @@ -1682,10 +1682,10 @@ encoder_bridge_enable(struct drm_device *dev, struct drm_atomic_state *state) void drm_atomic_helper_commit_modeset_enables(struct drm_device *dev, struct drm_atomic_state *state) { - encoder_bridge_pre_enable(dev, state); - crtc_enable(dev, state); + encoder_bridge_pre_enable(dev, state); + encoder_bridge_enable(dev, state); drm_atomic_helper_commit_writebacks(dev, state); diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h index 0ff7ab4aa868..dbafe136833f 100644 --- a/include/drm/drm_bridge.h +++ b/include/drm/drm_bridge.h @@ -176,33 +176,17 @@ struct drm_bridge_funcs { /** * @disable: * - * The @disable callback should disable the bridge. + * This callback should disable the bridge. It is called right before + * the preceding element in the display pipe is disabled. If the + * preceding element is a bridge this means it's called before that + * bridge's @disable vfunc. If the preceding element is a &drm_encoder + * it's called right before the &drm_encoder_helper_funcs.disable, + * &drm_encoder_helper_funcs.prepare or &drm_encoder_helper_funcs.dpms + * hook. * * The bridge can assume that the display pipe (i.e. clocks and timing * signals) feeding it is still running when this callback is called. * - * - * If the preceding element is a &drm_bridge, then this is called before - * that bridge is disabled via one of: - * - * - &drm_bridge_funcs.disable - * - &drm_bridge_funcs.atomic_disable - * - * If the preceding element of the bridge is a display controller, then - * this callback is called before the encoder is disabled via one of: - * - * - &drm_encoder_helper_funcs.atomic_disable - * - &drm_encoder_helper_funcs.prepare - * - &drm_encoder_helper_funcs.disable - * - &drm_encoder_helper_funcs.dpms - * - * and the CRTC is disabled via one of: - * - * - &drm_crtc_helper_funcs.prepare - * - &drm_crtc_helper_funcs.atomic_disable - * - &drm_crtc_helper_funcs.disable - * - &drm_crtc_helper_funcs.dpms. - * * The @disable callback is optional. * * NOTE: @@ -215,34 +199,17 @@ struct drm_bridge_funcs { /** * @post_disable: * + * This callback should disable the bridge. It is called right after the + * preceding element in the display pipe is disabled. If the preceding + * element is a bridge this means it's called after that bridge's + * @post_disable function. If the preceding element is a &drm_encoder + * it's called right after the encoder's + * &drm_encoder_helper_funcs.disable, &drm_encoder_helper_funcs.prepare + * or &drm_encoder_helper_funcs.dpms hook. + * * The bridge must assume that the display pipe (i.e. clocks and timing - * signals) feeding this bridge is no longer running when the - * @post_disable is called. - * - * This callback should perform all the actions required by the hardware - * after it has stopped receiving signals from the preceding element. - * - * If the preceding element is a &drm_bridge, then this is called after - * that bridge is post-disabled (unless marked otherwise by the - * @pre_enable_prev_first flag) via one of: - * - * - &drm_bridge_funcs.post_disable - * - &drm_bridge_funcs.atomic_post_disable - * - * If the preceding element of the bridge is a display controller, then - * this callback is called after the encoder is disabled via one of: - * - * - &drm_encoder_helper_funcs.atomic_disable - * - &drm_encoder_helper_funcs.prepare - * - &drm_encoder_helper_funcs.disable - * - &drm_encoder_helper_funcs.dpms - * - * and the CRTC is disabled via one of: - * - * - &drm_crtc_helper_funcs.prepare - * - &drm_crtc_helper_funcs.atomic_disable - * - &drm_crtc_helper_funcs.disable - * - &drm_crtc_helper_funcs.dpms + * signals) feeding it is no longer running when this callback is + * called. * * The @post_disable callback is optional. * @@ -285,30 +252,18 @@ struct drm_bridge_funcs { /** * @pre_enable: * + * This callback should enable the bridge. It is called right before + * the preceding element in the display pipe is enabled. If the + * preceding element is a bridge this means it's called before that + * bridge's @pre_enable function. If the preceding element is a + * &drm_encoder it's called right before the encoder's + * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or + * &drm_encoder_helper_funcs.dpms hook. + * * The display pipe (i.e. clocks and timing signals) feeding this bridge - * will not yet be running when the @pre_enable is called. - * - * This callback should perform all the necessary actions to prepare the - * bridge to accept signals from the preceding element. - * - * If the preceding element is a &drm_bridge, then this is called before - * that bridge is pre-enabled (unless marked otherwise by - * @pre_enable_prev_first flag) via one of: - * - * - &drm_bridge_funcs.pre_enable - * - &drm_bridge_funcs.atomic_pre_enable - * - * If the preceding element of the bridge is a display controller, then - * this callback is called before the CRTC is enabled via one of: - * - * - &drm_crtc_helper_funcs.atomic_enable - * - &drm_crtc_helper_funcs.commit - * - * and the encoder is enabled via one of: - * - * - &drm_encoder_helper_funcs.atomic_enable - * - &drm_encoder_helper_funcs.enable - * - &drm_encoder_helper_funcs.commit + * will not yet be running when this callback is called. The bridge must + * not enable the display link feeding the next bridge in the chain (if + * there is one) when this callback is called. * * The @pre_enable callback is optional. * @@ -322,31 +277,19 @@ struct drm_bridge_funcs { /** * @enable: * - * The @enable callback should enable the bridge. + * This callback should enable the bridge. It is called right after + * the preceding element in the display pipe is enabled. If the + * preceding element is a bridge this means it's called after that + * bridge's @enable function. If the preceding element is a + * &drm_encoder it's called right after the encoder's + * &drm_encoder_helper_funcs.enable, &drm_encoder_helper_funcs.commit or + * &drm_encoder_helper_funcs.dpms hook. * * The bridge can assume that the display pipe (i.e. clocks and timing * signals) feeding it is running when this callback is called. This * callback must enable the display link feeding the next bridge in the * chain if there is one. * - * If the preceding element is a &drm_bridge, then this is called after - * that bridge is enabled via one of: - * - * - &drm_bridge_funcs.enable - * - &drm_bridge_funcs.atomic_enable - * - * If the preceding element of the bridge is a display controller, then - * this callback is called after the CRTC is enabled via one of: - * - * - &drm_crtc_helper_funcs.atomic_enable - * - &drm_crtc_helper_funcs.commit - * - * and the encoder is enabled via one of: - * - * - &drm_encoder_helper_funcs.atomic_enable - * - &drm_encoder_helper_funcs.enable - * - drm_encoder_helper_funcs.commit - * * The @enable callback is optional. * * NOTE: @@ -359,30 +302,17 @@ struct drm_bridge_funcs { /** * @atomic_pre_enable: * + * This callback should enable the bridge. It is called right before + * the preceding element in the display pipe is enabled. If the + * preceding element is a bridge this means it's called before that + * bridge's @atomic_pre_enable or @pre_enable function. If the preceding + * element is a &drm_encoder it's called right before the encoder's + * &drm_encoder_helper_funcs.atomic_enable hook. + * * The display pipe (i.e. clocks and timing signals) feeding this bridge - * will not yet be running when the @atomic_pre_enable is called. - * - * This callback should perform all the necessary actions to prepare the - * bridge to accept signals from the preceding element. - * - * If the preceding element is a &drm_bridge, then this is called before - * that bridge is pre-enabled (unless marked otherwise by - * @pre_enable_prev_first flag) via one of: - * - * - &drm_bridge_funcs.pre_enable - * - &drm_bridge_funcs.atomic_pre_enable - * - * If the preceding element of the bridge is a display controller, then - * this callback is called before the CRTC is enabled via one of: - * - * - &drm_crtc_helper_funcs.atomic_enable - * - &drm_crtc_helper_funcs.commit - * - * and the encoder is enabled via one of: - * - * - &drm_encoder_helper_funcs.atomic_enable - * - &drm_encoder_helper_funcs.enable - * - &drm_encoder_helper_funcs.commit + * will not yet be running when this callback is called. The bridge must + * not enable the display link feeding the next bridge in the chain (if + * there is one) when this callback is called. * * The @atomic_pre_enable callback is optional. */ @@ -392,31 +322,18 @@ struct drm_bridge_funcs { /** * @atomic_enable: * - * The @atomic_enable callback should enable the bridge. + * This callback should enable the bridge. It is called right after + * the preceding element in the display pipe is enabled. If the + * preceding element is a bridge this means it's called after that + * bridge's @atomic_enable or @enable function. If the preceding element + * is a &drm_encoder it's called right after the encoder's + * &drm_encoder_helper_funcs.atomic_enable hook. * * The bridge can assume that the display pipe (i.e. clocks and timing * signals) feeding it is running when this callback is called. This * callback must enable the display link feeding the next bridge in the * chain if there is one. * - * If the preceding element is a &drm_bridge, then this is called after - * that bridge is enabled via one of: - * - * - &drm_bridge_funcs.enable - * - &drm_bridge_funcs.atomic_enable - * - * If the preceding element of the bridge is a display controller, then - * this callback is called after the CRTC is enabled via one of: - * - * - &drm_crtc_helper_funcs.atomic_enable - * - &drm_crtc_helper_funcs.commit - * - * and the encoder is enabled via one of: - * - * - &drm_encoder_helper_funcs.atomic_enable - * - &drm_encoder_helper_funcs.enable - * - drm_encoder_helper_funcs.commit - * * The @atomic_enable callback is optional. */ void (*atomic_enable)(struct drm_bridge *bridge, @@ -424,32 +341,16 @@ struct drm_bridge_funcs { /** * @atomic_disable: * - * The @atomic_disable callback should disable the bridge. + * This callback should disable the bridge. It is called right before + * the preceding element in the display pipe is disabled. If the + * preceding element is a bridge this means it's called before that + * bridge's @atomic_disable or @disable vfunc. If the preceding element + * is a &drm_encoder it's called right before the + * &drm_encoder_helper_funcs.atomic_disable hook. * * The bridge can assume that the display pipe (i.e. clocks and timing * signals) feeding it is still running when this callback is called. * - * If the preceding element is a &drm_bridge, then this is called before - * that bridge is disabled via one of: - * - * - &drm_bridge_funcs.disable - * - &drm_bridge_funcs.atomic_disable - * - * If the preceding element of the bridge is a display controller, then - * this callback is called before the encoder is disabled via one of: - * - * - &drm_encoder_helper_funcs.atomic_disable - * - &drm_encoder_helper_funcs.prepare - * - &drm_encoder_helper_funcs.disable - * - &drm_encoder_helper_funcs.dpms - * - * and the CRTC is disabled via one of: - * - * - &drm_crtc_helper_funcs.prepare - * - &drm_crtc_helper_funcs.atomic_disable - * - &drm_crtc_helper_funcs.disable - * - &drm_crtc_helper_funcs.dpms. - * * The @atomic_disable callback is optional. */ void (*atomic_disable)(struct drm_bridge *bridge, @@ -458,34 +359,16 @@ struct drm_bridge_funcs { /** * @atomic_post_disable: * + * This callback should disable the bridge. It is called right after the + * preceding element in the display pipe is disabled. If the preceding + * element is a bridge this means it's called after that bridge's + * @atomic_post_disable or @post_disable function. If the preceding + * element is a &drm_encoder it's called right after the encoder's + * &drm_encoder_helper_funcs.atomic_disable hook. + * * The bridge must assume that the display pipe (i.e. clocks and timing - * signals) feeding this bridge is no longer running when the - * @atomic_post_disable is called. - * - * This callback should perform all the actions required by the hardware - * after it has stopped receiving signals from the preceding element. - * - * If the preceding element is a &drm_bridge, then this is called after - * that bridge is post-disabled (unless marked otherwise by the - * @pre_enable_prev_first flag) via one of: - * - * - &drm_bridge_funcs.post_disable - * - &drm_bridge_funcs.atomic_post_disable - * - * If the preceding element of the bridge is a display controller, then - * this callback is called after the encoder is disabled via one of: - * - * - &drm_encoder_helper_funcs.atomic_disable - * - &drm_encoder_helper_funcs.prepare - * - &drm_encoder_helper_funcs.disable - * - &drm_encoder_helper_funcs.dpms - * - * and the CRTC is disabled via one of: - * - * - &drm_crtc_helper_funcs.prepare - * - &drm_crtc_helper_funcs.atomic_disable - * - &drm_crtc_helper_funcs.disable - * - &drm_crtc_helper_funcs.dpms + * signals) feeding it is no longer running when this callback is + * called. * * The @atomic_post_disable callback is optional. */ -- 2.52.0