From mboxrd@z Thu Jan 1 00:00:00 1970 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id A9EE0CD3430 for ; Mon, 4 May 2026 15:22:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=eAK0NVDTXgfOyaDOAEDsii3ti5HHZ+55PJPDlnkFlQk=; b=mOYe/l6cc8v/RfL14mx3PsHc3F hU5/JAgRAbEWMpJT3crIV9f22tNmHrr+L0s3a41dI7fsJtqPvb0mnSOxdbovvltMy+OuVlazqAYJY C+tstO3eq1GhwvsEsy8+ND1UoiWwkNGRvjHXcjwG9pNf4rwAGAc3ZumzKrhIusQEqnsPaF7KMEDSj /Vq48G6Cpa2EpcrWxWAdVOU+OVV/jnExU9PC+tLDltoGlID3ZxtEtLs+LrxQkn4/Y8n34A8DMRvk2 oGt/t1FH2L9wB8041ZnyHmx/BLK4cLB/LvekIC6BjbiVwyVK0HP7XP0imIrXu2ZlQMiUxovj5Lrsa kiF9nTUg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1wJv7w-0000000DahR-2sdK; Mon, 04 May 2026 15:22:32 +0000 Received: from perceval.ideasonboard.com ([213.167.242.64]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1wJv7u-0000000Dah6-0HRd for linux-arm-kernel@lists.infradead.org; Mon, 04 May 2026 15:22:31 +0000 Received: from killaraus.ideasonboard.com (2001-14ba-703d-e500--2a1.rev.dnainternet.fi [IPv6:2001:14ba:703d:e500::2a1]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 183FC175; Mon, 4 May 2026 17:22:26 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1777908146; bh=zqH6L+EG9wUTO7Qoyz4neBCPa6T/Ac/tjYvnTvOAB7Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GHXtwh5T5BDC8Q9lFPK/5JEuWFjkhO2o8t8eJUO5EnQigc23poa+JjvgYhTAKT0fZ 2WAfqiKfoaQQcpeFgC0FcTCWmZWo3te0QcHcWFshgYdHWgitgFsqCdYFkqpJQIapQY LQ0xWLVZ2ygWK/cNBfWeyY0dm7tXSECuDWeQGXVI= Date: Mon, 4 May 2026 18:22:26 +0300 From: Laurent Pinchart To: Luca Ceresoli Cc: Andrzej Hajda , Neil Armstrong , Robert Foss , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Rob Clark , Dmitry Baryshkov , Abhinav Kumar , Jessica Zhang , Sean Paul , Marijn Suijten , Sumit Semwal , John Stultz , Tomi Valkeinen , Michal Simek , Hui Pu , Ian Ray , Thomas Petazzoni , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, freedreno@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, Biju Das , Dmitry Baryshkov Subject: Re: [PATCH v4 08/11] drm/bridge: adv7511: switch to of_drm_get_bridge_by_endpoint() Message-ID: <20260504152226.GB1455860@killaraus.ideasonboard.com> References: <20260504-drm-bridge-alloc-getput-panel_or_bridge-v4-0-b578c3daaf10@bootlin.com> <20260504-drm-bridge-alloc-getput-panel_or_bridge-v4-8-b578c3daaf10@bootlin.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20260504-drm-bridge-alloc-getput-panel_or_bridge-v4-8-b578c3daaf10@bootlin.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260504_082230_248493_02D9B357 X-CRM114-Status: GOOD ( 22.03 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Luca, Thank you for the patch. On Mon, May 04, 2026 at 12:45:11PM +0200, Luca Ceresoli wrote: > This driver calls drm_of_find_panel_or_bridge() with a NULL pointer in the > @panel parameter, thus using a reduced feature set of that function. > Replace this call with the simpler of_drm_get_bridge_by_endpoint(). > > Since of_drm_get_bridge_by_endpoint() increases the refcount of the > returned bridge, ensure it is put on removal. To achieve this, instead of > adding an explicit drm_bridge_put(), migrate to the bridge::next_bridge > pointer which is automatically put when the bridge is eventually freed. > > Tested-by: Biju Das > Reviewed-by: Dmitry Baryshkov > Signed-off-by: Luca Ceresoli Reviewed-by: Laurent Pinchart > --- > Changes in v3: > - fix ERR_PTR deref when -ENODEV is returned > --- > drivers/gpu/drm/bridge/adv7511/adv7511.h | 1 - > drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 15 +++++++++------ > 2 files changed, 9 insertions(+), 7 deletions(-) > > diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511.h b/drivers/gpu/drm/bridge/adv7511/adv7511.h > index 8be7266fd4f4..12c95198d9a4 100644 > --- a/drivers/gpu/drm/bridge/adv7511/adv7511.h > +++ b/drivers/gpu/drm/bridge/adv7511/adv7511.h > @@ -354,7 +354,6 @@ struct adv7511 { > enum drm_connector_status status; > bool powered; > > - struct drm_bridge *next_bridge; > struct drm_display_mode curr_mode; > > unsigned int f_tmds; > diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > index f318080f1139..8304978535e4 100644 > --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c > @@ -849,8 +849,8 @@ static int adv7511_bridge_attach(struct drm_bridge *bridge, > struct adv7511 *adv = bridge_to_adv7511(bridge); > int ret = 0; > > - if (adv->next_bridge) { > - ret = drm_bridge_attach(encoder, adv->next_bridge, bridge, > + if (adv->bridge.next_bridge) { > + ret = drm_bridge_attach(encoder, adv->bridge.next_bridge, bridge, > flags | DRM_BRIDGE_ATTACH_NO_CONNECTOR); > if (ret) > return ret; > @@ -1249,10 +1249,13 @@ static int adv7511_probe(struct i2c_client *i2c) > > memset(&link_config, 0, sizeof(link_config)); > > - ret = drm_of_find_panel_or_bridge(dev->of_node, 1, -1, NULL, > - &adv7511->next_bridge); > - if (ret && ret != -ENODEV) > - return ret; > + adv7511->bridge.next_bridge = of_drm_get_bridge_by_endpoint(dev->of_node, 1, -1); > + if (IS_ERR(adv7511->bridge.next_bridge)) { > + if (PTR_ERR(adv7511->bridge.next_bridge) == -ENODEV) > + adv7511->bridge.next_bridge = NULL; > + else > + return PTR_ERR(adv7511->bridge.next_bridge); > + } > > if (adv7511->info->link_config) > ret = adv7511_parse_dt(dev->of_node, &link_config); -- Regards, Laurent Pinchart