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Message-ID: <5a1934848d855881e769fc3263891f60@kernel.org>
Date: Mon, 22 Jun 2026 09:06:24 +0000
From: "Maxime Ripard" <mripard@kernel.org>
To: "Nicolas Frattaroli" <nicolas.frattaroli@collabora.com>
Subject: Re: [PATCH v3 1/2] drm/display: hdmi: Only allow BPC values of 8,
 10, 12 and 16
In-Reply-To: <20260619-hdmi-max-bpc-fix-v3-1-ba83e5361eb0@collabora.com>
References: <20260619-hdmi-max-bpc-fix-v3-1-ba83e5361eb0@collabora.com>
Cc: dri-devel@lists.freedesktop.org, kernel@collabora.com,
 linux-kernel@vger.kernel.org, "David
 Airlie" <airlied@gmail.com>, "Dmitry Baryshkov" <lumag@kernel.org>, "Maarten
 Lankhorst" <maarten.lankhorst@linux.intel.com>,
 "Maxime Ripard" <mripard@kernel.org>, "Simona
 Vetter" <simona@ffwll.ch>, "Thomas Zimmermann" <tzimmermann@suse.de>
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On Fri, 19 Jun 2026 16:37:31 +0200, Nicolas Frattaroli wrote:
> As per the comment in sink_supports_format_bpc(), CTA-861-F defines that
> only bits-per-channel values of 8, 10, 12 and 16 are allowed for HDMI.
> Allowing more than this has surprising consequences for the atomic check
> phase. The HDMI state helpers may accidentally conclude that a sink
> supports 11bpc if a caller asks for it.
> 
> [ ... ]

Reviewed-by: Maxime Ripard <mripard@kernel.org>

Thanks!
Maxime