From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (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 B04E625A645; Wed, 8 Apr 2026 21:32:01 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775683923; cv=none; b=Ij1AjEwUv4JDt6b0fWvy3YgEZ9xXz/BTHMLmo3TXBL4A1Jfo/QytOKVjngfqwhr/n3qga8K6mBbBhQmDXixxX+ib15k8upK/hPkaxFEySQDdaWm14RRLHSPjfFTYTlluOX16KPN0WwhzR2NKSCdq7uw2HXaRzPe2ug5BHsjEfEI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775683923; c=relaxed/simple; bh=oAC1/K/V1XBRxFt3ULj40F2D7Cto95HCk2G145TRZY0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=PFeAeUSkJVry92VSA0LcfPoDHeiQ3SsntqK/Ry17S+/OMINnxENETeNzclatRQbf/RLh28qkZ6P0pVXgcAyEMmWZHLnYxC9idyiGyxFNNX5L+agKZ7zuIWU2wFCAWdd+2R3IiLf7dJazj/1aLvCcUjNayCvvSjY/vX3FUvYfQ0g= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=gMSp+Qwn; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="gMSp+Qwn" 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 UTF8SMTPSA id D3172241; Wed, 8 Apr 2026 23:30:29 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1775683830; bh=oAC1/K/V1XBRxFt3ULj40F2D7Cto95HCk2G145TRZY0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gMSp+QwnN623dVRBFHiTqntRHjnCxX1D7YwQcxPqxZo/B5D3P7rtrGdZDclkKs3K6 XAMs6yUVUXOwkY7ATV1KKf5OIeFChkeqG2ySh98XyuaD/Oz5Fm6yxAMo9pFqVqOvo2 OxXwL4uwsRgyvNTgQQWDHC2MBzix6SyMICGLx3W0= Date: Thu, 9 Apr 2026 00:31:56 +0300 From: Laurent Pinchart To: Louis Chauvet Cc: Luca Ceresoli , Biju Das , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Anitha Chrisanthus , Linus Walleij , Tomi Valkeinen , Kieran Bingham , Geert Uytterhoeven , Magnus Damm , Tomi Valkeinen , Hui Pu , Ian Ray , Thomas Petazzoni , dri-devel@lists.freedesktop.org, linux-renesas-soc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 3/4] drm: rcar-du: encoder: convert to of_drm_find_and_get_bridge() Message-ID: <20260408213156.GL1965119@killaraus.ideasonboard.com> References: <20260402-drm-bridge-alloc-getput-drm_of_find_bridge-4-v4-0-421781c8c061@bootlin.com> <20260402-drm-bridge-alloc-getput-drm_of_find_bridge-4-v4-3-421781c8c061@bootlin.com> <4cd29943-a8d0-4706-b0c5-01d6b33863e4@bootlin.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <4cd29943-a8d0-4706-b0c5-01d6b33863e4@bootlin.com> On Wed, Apr 08, 2026 at 06:03:01PM +0200, Louis Chauvet wrote: > On 4/2/26 18:27, Luca Ceresoli wrote: > > of_drm_find_bridge() is deprecated. Move to its replacement > > of_drm_find_and_get_bridge() which gets a bridge reference, and ensure it > > is put when done. > > > > We need to handle the two cases: when a panel_bridge is added and when it > > isn't. So: > > > > * in the 'else' case a panel_bridge is not added and bridge is found: use > > of_drm_find_and_get_bridge() to get a reference to the found bridge > > * in the 'then' case a panel_bridge is found using a devm function which > > already takes a refcount and will put it on removal, but we need to take > > another so the following code in this function always get exactly one > > reference that it needs to put > > > > In order to put the reference, add the needed drm_bridge_put() calls in the > > existing cleanup function. > > > > Signed-off-by: Luca Ceresoli > > > > --- > > > > Changes in v4: > > - fixed conflict after commit 3bce3fdd1ff2 ("drm: rcar-du: Don't leak > > device_link to CMM") > > - Use ARRAY_SIZE() instead of define > > - Unsigned variable for never-negative variable > > - Added comment to clarify the additional drm_bridge_get() in the > > panel_bridge case > > - Coding style (C comments, line wrap at 80) > > --- > > drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c | 35 +++++++++++++++++++---- > > drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.h | 1 + > > drivers/gpu/drm/renesas/rcar-du/rcar_du_kms.c | 2 ++ > > 3 files changed, 32 insertions(+), 6 deletions(-) > > > > diff --git a/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c b/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c > > index 7ecec7b04a8d..0ae06edf3066 100644 > > --- a/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c > > +++ b/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.c > > @@ -51,7 +51,7 @@ int rcar_du_encoder_init(struct rcar_du_device *rcdu, > > { > > struct rcar_du_encoder *renc; > > struct drm_connector *connector; > > - struct drm_bridge *bridge; > > + struct drm_bridge *bridge __free(drm_bridge_put) = NULL; > > int ret; > > > > /* > > @@ -69,20 +69,33 @@ int rcar_du_encoder_init(struct rcar_du_device *rcdu, > > > > bridge = devm_drm_panel_bridge_add_typed(rcdu->dev, panel, > > DRM_MODE_CONNECTOR_DPI); > > - if (IS_ERR(bridge)) > > - return PTR_ERR(bridge); > > + if (IS_ERR(bridge)) { > > + /* Inhibit the cleanup action on an ERR_PTR */ > > + ret = PTR_ERR(bridge); > > + bridge = NULL; > > + return ret; > > Same as before, can you use no_free_ptr? That would be nice. You could then drop the comment, as no_free_ptr makes it explicit. Reviewed-by: Laurent Pinchart > With or without this modification: > > Reviewed-by: Louis Chauvet > > > + } > > + > > + /* > > + * The reference taken by devm_drm_panel_bridge_add_typed() is > > + * released automatically. Take a second one for the __free() > > + * when this function will return. > > + */ > > + drm_bridge_get(bridge); > > } else { > > - bridge = of_drm_find_bridge(enc_node); > > + bridge = of_drm_find_and_get_bridge(enc_node); > > if (!bridge) > > return -EPROBE_DEFER; > > > > if (output == RCAR_DU_OUTPUT_LVDS0 || > > output == RCAR_DU_OUTPUT_LVDS1) > > - rcdu->lvds[output - RCAR_DU_OUTPUT_LVDS0] = bridge; > > + rcdu->lvds[output - RCAR_DU_OUTPUT_LVDS0] = > > + drm_bridge_get(bridge); > > > > if (output == RCAR_DU_OUTPUT_DSI0 || > > output == RCAR_DU_OUTPUT_DSI1) > > - rcdu->dsi[output - RCAR_DU_OUTPUT_DSI0] = bridge; > > + rcdu->dsi[output - RCAR_DU_OUTPUT_DSI0] = > > + drm_bridge_get(bridge); > > } > > > > /* > > @@ -135,3 +148,13 @@ int rcar_du_encoder_init(struct rcar_du_device *rcdu, > > > > return drm_connector_attach_encoder(connector, &renc->base); > > } > > + > > +void rcar_du_encoder_cleanup(struct rcar_du_device *rcdu) > > +{ > > + unsigned int i; > > + > > + for (i = 0; i < ARRAY_SIZE(rcdu->lvds); i++) > > + drm_bridge_put(rcdu->lvds[i]); > > + for (i = 0; i < ARRAY_SIZE(rcdu->dsi); i++) > > + drm_bridge_put(rcdu->dsi[i]); > > +} > > diff --git a/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.h b/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.h > > index e5ec8fbb3979..b2b5e93f30f8 100644 > > --- a/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.h > > +++ b/drivers/gpu/drm/renesas/rcar-du/rcar_du_encoder.h > > @@ -25,5 +25,6 @@ struct rcar_du_encoder { > > int rcar_du_encoder_init(struct rcar_du_device *rcdu, > > enum rcar_du_output output, > > struct device_node *enc_node); > > +void rcar_du_encoder_cleanup(struct rcar_du_device *rcdu); > > > > #endif /* __RCAR_DU_ENCODER_H__ */ > > diff --git a/drivers/gpu/drm/renesas/rcar-du/rcar_du_kms.c b/drivers/gpu/drm/renesas/rcar-du/rcar_du_kms.c > > index b2d0e4651e35..1119c84e5fe9 100644 > > --- a/drivers/gpu/drm/renesas/rcar-du/rcar_du_kms.c > > +++ b/drivers/gpu/drm/renesas/rcar-du/rcar_du_kms.c > > @@ -832,6 +832,8 @@ static void rcar_du_modeset_cleanup(struct drm_device *dev, void *res) > > > > put_device(cmm->dev); > > } > > + > > + rcar_du_encoder_cleanup(rcdu); > > } > > > > int rcar_du_modeset_init(struct rcar_du_device *rcdu) > > -- Regards, Laurent Pinchart