linux-kernel - Re: [PATCH] drm/bridge: ite-it6263: Support HDMI vendor specific infoframe

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]

Message-ID: <6i7eyxajmelu3x4ckvwifmizln6jzybt6ykpwlefna3k3noop4@e5zdvzor24fn>
Date: Fri, 5 Sep 2025 01:40:53 +0300
From: Dmitry Baryshkov <dmitry.baryshkov@....qualcomm.com>
To: Liu Ying <victor.liu@....com>
Cc: 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>,
        Maxime Ripard <mripard@...nel.org>,
        Thomas Zimmermann <tzimmermann@...e.de>,
        David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>,
        Dmitry Baryshkov <lumag@...nel.org>, dri-devel@...ts.freedesktop.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] drm/bridge: ite-it6263: Support HDMI vendor specific
 infoframe

On Thu, Sep 04, 2025 at 05:10:02PM +0800, Liu Ying wrote:
> IT6263 supports HDMI vendor specific infoframe.  The infoframe header
> and payload are configurable via NULL packet registers.  The infoframe
> is enabled and disabled via PKT_NULL_CTRL register.  Add the HDMI vendor
> specific infoframe support.
> 
> Signed-off-by: Liu Ying <victor.liu@....com>
> ---
>  drivers/gpu/drm/bridge/ite-it6263.c | 72 ++++++++++++++++++++++++++-----------
>  1 file changed, 52 insertions(+), 20 deletions(-)
> 
> +	case HDMI_INFOFRAME_TYPE_VENDOR:
> +		const char zero_bulk[HDMI_PKT_HB_PB_CHUNK_SIZE] = { };
> +
> +		/* clear NULL packet registers due to undefined default value */
> +		regmap_bulk_write(regmap, HDMI_REG_PKT_HB(0),
> +				  zero_bulk, sizeof(zero_bulk));

What if you move this to the probe function? Then there will be no need
to write those registers each time the infoframe is being written.

LGTM otherwise.

> +
> +		/* write header and payload */
> +		regmap_bulk_write(regmap, HDMI_REG_PKT_HB(0), buffer, len);
> +
> +		regmap_write(regmap, HDMI_REG_PKT_NULL_CTRL,
> +			     ENABLE_PKT | REPEAT_PKT);
> +		break;

-- 
With best wishes
Dmitry