linux-kernel - Re: [PATCH] drm/bridge: imx: Remove redundant checks on existence of bridge->encoder

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Mon, 13 May 2024 13:56:40 +0800
From: Liu Ying <victor.liu@....com>
To: Sui Jingfeng <sui.jingfeng@...ux.dev>, Shawn Guo <shawnguo@...nel.org>,
 Sascha Hauer <s.hauer@...gutronix.de>, Fabio Estevam <festevam@...il.com>
Cc: Pengutronix Kernel Team <kernel@...gutronix.de>,
 Maxime Ripard <mripard@...nel.org>, Andrzej Hajda <andrzej.hajda@...el.com>,
 Neil Armstrong <neil.armstrong@...aro.org>, Robert Foss <rfoss@...nel.org>,
 Laurent Pinchart <Laurent.pinchart@...asonboard.com>,
 Jonas Karlman <jonas@...boo.se>, Jernej Skrabec <jernej.skrabec@...il.com>,
 Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
 Thomas Zimmermann <tzimmermann@...e.de>, dri-devel@...ts.freedesktop.org,
 linux-kernel@...r.kernel.org
Subject: Re: [PATCH] drm/bridge: imx: Remove redundant checks on existence of
 bridge->encoder

On 5/11/24 23:08, Sui Jingfeng wrote:
> The check on the existence of bridge->encoder on the implementation layer
> of drm bridge driver is not necessary, as it has already been done in the
> drm_bridge_attach() function. It is guaranteed that the .encoder member
> of the drm_bridge instance is not NULL when various imx_xxx_bridge_attach()
> function gets called.

Nit:
ldb_bridge_attach_helper() doesn't follow the fashion of
imx_xxx_bridge_attach(), not even the other bridge attach
functions touched by this patch do.  Maybe, reword as
"when various i.MX specific bridge attach functions are
called."

Regards,
Liu Ying

> 
> Remove the redundant checking codes "if (!bridge->encoder) { ... }".
> 
> Signed-off-by: Sui Jingfeng <sui.jingfeng@...ux.dev>
> ---
>  drivers/gpu/drm/bridge/imx/imx-ldb-helper.c         | 5 -----
>  drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c | 5 -----
>  drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c     | 5 -----
>  drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c        | 5 -----
>  4 files changed, 20 deletions(-)
> 
> diff --git a/drivers/gpu/drm/bridge/imx/imx-ldb-helper.c b/drivers/gpu/drm/bridge/imx/imx-ldb-helper.c
> index 6967325cd8ee..9b5bebbe357d 100644
> --- a/drivers/gpu/drm/bridge/imx/imx-ldb-helper.c
> +++ b/drivers/gpu/drm/bridge/imx/imx-ldb-helper.c
> @@ -116,11 +116,6 @@ int ldb_bridge_attach_helper(struct drm_bridge *bridge,
>  		return -EINVAL;
>  	}
>  
> -	if (!bridge->encoder) {
> -		DRM_DEV_ERROR(ldb->dev, "missing encoder\n");
> -		return -ENODEV;
> -	}
> -
>  	return drm_bridge_attach(bridge->encoder,
>  				ldb_ch->next_bridge, bridge,
>  				DRM_BRIDGE_ATTACH_NO_CONNECTOR);
> diff --git a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
> index d0868a6ac6c9..e6dbbdc87ce2 100644
> --- a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
> +++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-combiner.c
> @@ -119,11 +119,6 @@ static int imx8qxp_pc_bridge_attach(struct drm_bridge *bridge,
>  		return -EINVAL;
>  	}
>  
> -	if (!bridge->encoder) {
> -		DRM_DEV_ERROR(pc->dev, "missing encoder\n");
> -		return -ENODEV;
> -	}
> -
>  	return drm_bridge_attach(bridge->encoder,
>  				 ch->next_bridge, bridge,
>  				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
> diff --git a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c
> index ed8b7a4e0e11..1d11cc1df43c 100644
> --- a/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c
> +++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pixel-link.c
> @@ -138,11 +138,6 @@ static int imx8qxp_pixel_link_bridge_attach(struct drm_bridge *bridge,
>  		return -EINVAL;
>  	}
>  
> -	if (!bridge->encoder) {
> -		DRM_DEV_ERROR(pl->dev, "missing encoder\n");
> -		return -ENODEV;
> -	}
> -
>  	return drm_bridge_attach(bridge->encoder,
>  				 pl->next_bridge, bridge,
>  				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);
> diff --git a/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c b/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c
> index 4a886cb808ca..fb7cf4369bb8 100644
> --- a/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c
> +++ b/drivers/gpu/drm/bridge/imx/imx8qxp-pxl2dpi.c
> @@ -58,11 +58,6 @@ static int imx8qxp_pxl2dpi_bridge_attach(struct drm_bridge *bridge,
>  		return -EINVAL;
>  	}
>  
> -	if (!bridge->encoder) {
> -		DRM_DEV_ERROR(p2d->dev, "missing encoder\n");
> -		return -ENODEV;
> -	}
> -
>  	return drm_bridge_attach(bridge->encoder,
>  				 p2d->next_bridge, bridge,
>  				 DRM_BRIDGE_ATTACH_NO_CONNECTOR);