From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 536503F660B; Wed, 20 May 2026 18:05:43 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779300344; cv=none; b=G6OGwtQZbeAe/VwfIttiejFqh7PL5yf5l8CAuwM/WeSoN6FLKD20lik9btJx4lgIn0uIgOenAWOMsZ/OBwBkdHelMy40wSln1ylLnNH6BstIVmRwiPBcGuRDFukbg1HHOfxs3iA2GzscyXC6yYlsyOPSK63opcmkFMitw3bjc1Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779300344; c=relaxed/simple; bh=9UqwEvIDG8If6DgS7pHeZHVky7s+5rWT9J3nejlYnHw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=lnglPu/mnRCpXzPAdiWc3hegZ2+444eWltQXk+7GetVm1LU47iQ8q+5lEymVfV1QZbIlt3QBr+g35EkVN23K+FGVfmHzEqE3iHTmAgGwhxN3UvYkp3XD7mdHZ5ExNvH/WHHo5YoVjhuzZAXC/7xDfMjoOfNXjGFUzmeoaIy7ggs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1R9OUTK/; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="1R9OUTK/" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B96261F000E9; Wed, 20 May 2026 18:05:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1779300343; bh=NNGaGhl2EpnSpVzkV3AKlG77xt3FfNhYMdZCEqXPRgw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=1R9OUTK/6qtkdBMUDuyyFNKP1LQepaMD/Nq3toDthKKt9sef/A1dTHTxpKXyQrH1W 0BeK9LyQ7FtbD8u+7e/wzU1uUB72KExyvQ6ShFKO/IUpEiv6RznMi97F4X4I6uiztc 28WNNbyXWTc6x15pbXrX+k42Y0hy5IloeLcVYkKQ= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jayesh Choudhary , Harikrishna Shenoy , Luca Ceresoli , Tomi Valkeinen , Sasha Levin Subject: [PATCH 6.12 139/666] drm/bridge: cadence: cdns-mhdp8546-core: Set the mhdp connector earlier in atomic_enable() Date: Wed, 20 May 2026 18:15:50 +0200 Message-ID: <20260520162114.223955951@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260520162111.222830634@linuxfoundation.org> References: <20260520162111.222830634@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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jayesh Choudhary [ Upstream commit 43d6508ddbf9fb974fbc359a033154f78c9d4c8b ] In case if we get errors in cdns_mhdp_link_up() or cdns_mhdp_reg_read() in atomic_enable, we will go to cdns_mhdp_modeset_retry_fn() and will hit NULL pointer while trying to access the mutex. We need the connector to be set before that. Unlike in legacy cases with flag !DRM_BRIDGE_ATTACH_NO_CONNECTOR, we do not have connector initialised in bridge_attach(), so add the mhdp->connector_ptr in device structure to handle both cases with DRM_BRIDGE_ATTACH_NO_CONNECTOR and !DRM_BRIDGE_ATTACH_NO_CONNECTOR, set it in atomic_enable() earlier to avoid possible NULL pointer dereference in recovery paths like modeset_retry_fn() with the DRM_BRIDGE_ATTACH_NO_CONNECTOR flag set. Fixes: c932ced6b585 ("drm/tidss: Update encoder/bridge chain connect model") Signed-off-by: Jayesh Choudhary Signed-off-by: Harikrishna Shenoy Reviewed-by: Luca Ceresoli Reviewed-by: Tomi Valkeinen Link: https://patch.msgid.link/20251209120332.3559893-2-h-shenoy@ti.com Signed-off-by: Luca Ceresoli Signed-off-by: Sasha Levin --- .../drm/bridge/cadence/cdns-mhdp8546-core.c | 29 ++++++++++--------- .../drm/bridge/cadence/cdns-mhdp8546-core.h | 1 + .../drm/bridge/cadence/cdns-mhdp8546-hdcp.c | 18 +++++++++--- 3 files changed, 30 insertions(+), 18 deletions(-) diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c index b18bdb2daddf8..d718a908208f5 100644 --- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.c @@ -810,7 +810,7 @@ static void cdns_mhdp_fw_cb(const struct firmware *fw, void *context) bridge_attached = mhdp->bridge_attached; spin_unlock(&mhdp->start_lock); if (bridge_attached) { - if (mhdp->connector.dev) + if (mhdp->connector_ptr) drm_kms_helper_hotplug_event(mhdp->bridge.dev); else drm_bridge_hpd_notify(&mhdp->bridge, cdns_mhdp_detect(mhdp)); @@ -1706,6 +1706,7 @@ static int cdns_mhdp_connector_init(struct cdns_mhdp_device *mhdp) return ret; } + mhdp->connector_ptr = conn; drm_connector_helper_add(conn, &cdns_mhdp_conn_helper_funcs); ret = drm_display_info_set_bus_formats(&conn->display_info, @@ -1985,17 +1986,25 @@ static void cdns_mhdp_atomic_enable(struct drm_bridge *bridge, struct drm_atomic_state *state = bridge_state->base.state; struct cdns_mhdp_bridge_state *mhdp_state; struct drm_crtc_state *crtc_state; - struct drm_connector *connector; struct drm_connector_state *conn_state; struct drm_bridge_state *new_state; const struct drm_display_mode *mode; u32 resp; - int ret; + int ret = 0; dev_dbg(mhdp->dev, "bridge enable\n"); mutex_lock(&mhdp->link_mutex); + mhdp->connector_ptr = drm_atomic_get_new_connector_for_encoder(state, + bridge->encoder); + if (WARN_ON(!mhdp->connector_ptr)) + goto out; + + conn_state = drm_atomic_get_new_connector_state(state, mhdp->connector_ptr); + if (WARN_ON(!conn_state)) + goto out; + if (mhdp->plugged && !mhdp->link_up) { ret = cdns_mhdp_link_up(mhdp); if (ret < 0) @@ -2015,15 +2024,6 @@ static void cdns_mhdp_atomic_enable(struct drm_bridge *bridge, cdns_mhdp_reg_write(mhdp, CDNS_DPTX_CAR, resp | CDNS_VIF_CLK_EN | CDNS_VIF_CLK_RSTN); - connector = drm_atomic_get_new_connector_for_encoder(state, - bridge->encoder); - if (WARN_ON(!connector)) - goto out; - - conn_state = drm_atomic_get_new_connector_state(state, connector); - if (WARN_ON(!conn_state)) - goto out; - if (mhdp->hdcp_supported && mhdp->hw_state == MHDP_HW_READY && conn_state->content_protection == @@ -2100,6 +2100,7 @@ static void cdns_mhdp_atomic_disable(struct drm_bridge *bridge, if (mhdp->info && mhdp->info->ops && mhdp->info->ops->disable) mhdp->info->ops->disable(mhdp); + mhdp->connector_ptr = NULL; mutex_unlock(&mhdp->link_mutex); } @@ -2365,7 +2366,7 @@ static void cdns_mhdp_modeset_retry_fn(struct work_struct *work) mhdp = container_of(work, typeof(*mhdp), modeset_retry_work); - conn = &mhdp->connector; + conn = mhdp->connector_ptr; /* Grab the locks before changing connector property */ mutex_lock(&conn->dev->mode_config.mutex); @@ -2442,7 +2443,7 @@ static void cdns_mhdp_hpd_work(struct work_struct *work) int ret; ret = cdns_mhdp_update_link_status(mhdp); - if (mhdp->connector.dev) { + if (mhdp->connector_ptr) { if (ret < 0) schedule_work(&mhdp->modeset_retry_work); else diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h index bad2fc0c73066..a76775c768956 100644 --- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-core.h @@ -376,6 +376,7 @@ struct cdns_mhdp_device { struct mutex link_mutex; struct drm_connector connector; + struct drm_connector *connector_ptr; struct drm_bridge bridge; struct cdns_mhdp_link link; diff --git a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.c b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.c index 31832ba4017f1..3c8532d7f7841 100644 --- a/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.c +++ b/drivers/gpu/drm/bridge/cadence/cdns-mhdp8546-hdcp.c @@ -394,7 +394,7 @@ static int _cdns_mhdp_hdcp_disable(struct cdns_mhdp_device *mhdp) int ret; dev_dbg(mhdp->dev, "[%s:%d] HDCP is being disabled...\n", - mhdp->connector.name, mhdp->connector.base.id); + mhdp->connector_ptr->name, mhdp->connector_ptr->base.id); ret = cdns_mhdp_hdcp_set_config(mhdp, 0, false); @@ -436,6 +436,10 @@ static int cdns_mhdp_hdcp_check_link(struct cdns_mhdp_device *mhdp) int ret = 0; mutex_lock(&mhdp->hdcp.mutex); + + if (!mhdp->connector_ptr) + goto out; + if (mhdp->hdcp.value == DRM_MODE_CONTENT_PROTECTION_UNDESIRED) goto out; @@ -445,7 +449,7 @@ static int cdns_mhdp_hdcp_check_link(struct cdns_mhdp_device *mhdp) dev_err(mhdp->dev, "[%s:%d] HDCP link failed, retrying authentication\n", - mhdp->connector.name, mhdp->connector.base.id); + mhdp->connector_ptr->name, mhdp->connector_ptr->base.id); ret = _cdns_mhdp_hdcp_disable(mhdp); if (ret) { @@ -487,13 +491,19 @@ static void cdns_mhdp_hdcp_prop_work(struct work_struct *work) struct cdns_mhdp_device *mhdp = container_of(hdcp, struct cdns_mhdp_device, hdcp); - struct drm_device *dev = mhdp->connector.dev; + struct drm_device *dev = NULL; struct drm_connector_state *state; + if (mhdp->connector_ptr) + dev = mhdp->connector_ptr->dev; + + if (!dev) + return; + drm_modeset_lock(&dev->mode_config.connection_mutex, NULL); mutex_lock(&mhdp->hdcp.mutex); if (mhdp->hdcp.value != DRM_MODE_CONTENT_PROTECTION_UNDESIRED) { - state = mhdp->connector.state; + state = mhdp->connector_ptr->state; state->content_protection = mhdp->hdcp.value; } mutex_unlock(&mhdp->hdcp.mutex); -- 2.53.0