From nobody Fri Apr 3 03:14:53 2026 Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) (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 1070129E0E6; Tue, 24 Mar 2026 16:03:16 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.112 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774368198; cv=pass; b=tzphJxjY53eesHzM52yeVo/uU8i86XKBRSybafk7hx2hdunlma2l8i5ghbcMUStz6JQeP1teMnw+eeNLj1TV7glmCnySln2g0y0Iz1urndl9XxzkYWM/l0HLttAukLQnE20Sn+g5SEJ8wB2+V+YlRsehlhaajbVc66dd/OsZd/g= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774368198; c=relaxed/simple; bh=3BwOkFc/5J5YuOw+qhkDoH6STDj0TC3J/X6PQUqNomM=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=b4DxBqKFOiqkDxnEtKK0jDQRJZ9EDQEQNe9c90FelbLtpDQcFLoSF9oSDoCKsIHOSsAKvICKEAL7uzv7k9Xl7gkhmWlz+Oolxi4/lJ6F/8QwjoGN9LZkWd0wztQKOcnwBqoJURRk2lEHsV8JM3vea3J7M0qJuVdqcilRcywTS5Q= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=nicolas.frattaroli@collabora.com header.b=bL8HYVxS; arc=pass smtp.client-ip=136.143.188.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=nicolas.frattaroli@collabora.com header.b="bL8HYVxS" ARC-Seal: i=1; a=rsa-sha256; t=1774368151; cv=none; d=zohomail.com; s=zohoarc; b=UQQkzW8hNoLun6nyBbgWt9ISGKM1w/1+pBxEoda6CTfmLl/TJbsptfHD9E/u18F48q41hzZEBXzj/4G6qn8GsUox0IE6Pcolqq7Na+8UPad2AvHUAFNGCBUQiMFU6lnnMOsuLp3/5ptcU6ZuVPkbohXDYcj/WB9i/ZK/UkohTW4= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1774368151; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=MC7m65enPeoK56w15mZU/jnX37Exa8SW0qeHJO7INHM=; b=hVMKmC3mIeZH5KCnvTcz3a+PG9s/9HhLLXzZplsax8d7RmvqwBJNlFYR1ewt5eTiOTCqbX7vY/63+PoGcCtv/8r/UPFiZGfYhAQkdgG3u1FVa/eyCzttfqlTFiMGjakFB0/caOW0/4kNsjGDxF1cnQyxoBvFO9BtD3cZRKyYZ1U= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=nicolas.frattaroli@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1774368151; s=zohomail; d=collabora.com; i=nicolas.frattaroli@collabora.com; h=From:From:Date:Date:Subject:Subject:MIME-Version:Content-Type:Content-Transfer-Encoding:Message-Id:Message-Id:References:In-Reply-To:To:To:Cc:Cc:Reply-To; bh=MC7m65enPeoK56w15mZU/jnX37Exa8SW0qeHJO7INHM=; b=bL8HYVxSbY+4CG4VhaT7Te2g+WpUHw7repMdPHmkh6qV9HOhfclGl8xWklo7D2HC KHUflc9abp9vWPkSmGk4FEpugS8vQDhEdGxweRoJDjcVqIZ6x6E2P7xBuu2ojIVMbGI PCv9jItORtnVulASKOmsvbeizzTSimsghjzNp7ms= Received: by mx.zohomail.com with SMTPS id 177436815050185.95818000717009; Tue, 24 Mar 2026 09:02:30 -0700 (PDT) From: Nicolas Frattaroli Date: Tue, 24 Mar 2026 17:01:11 +0100 Subject: [PATCH v11 07/22] drm/display: hdmi-state-helper: Try subsampling in mode_valid 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-Transfer-Encoding: quoted-printable Message-Id: <20260324-color-format-v11-7-605559af4fb4@collabora.com> References: <20260324-color-format-v11-0-605559af4fb4@collabora.com> In-Reply-To: <20260324-color-format-v11-0-605559af4fb4@collabora.com> To: Harry Wentland , Leo Li , Rodrigo Siqueira , Alex Deucher , =?utf-8?q?Christian_K=C3=B6nig?= , David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Sandy Huang , =?utf-8?q?Heiko_St=C3=BCbner?= , Andy Yan , Jani Nikula , Rodrigo Vivi , Joonas Lahtinen , Tvrtko Ursulin , Dmitry Baryshkov , Sascha Hauer , Rob Herring , Jonathan Corbet , Shuah Khan Cc: kernel@collabora.com, amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, intel-gfx@lists.freedesktop.org, intel-xe@lists.freedesktop.org, linux-doc@vger.kernel.org, Nicolas Frattaroli , Dmitry Baryshkov X-Mailer: b4 0.15.0 drm_hdmi_connector_mode_valid assumes modes are only valid if they work with RGB. The reality is more complex however: YCbCr 4:2:0 chroma-subsampled modes only require half the pixel clock that the same mode would require in RGB. This leads to drm_hdmi_connector_mode_valid rejecting perfectly valid 420-only or 420-also modes. Fix this by checking whether the mode is 420-capable first. If so, then proceed by checking it with DRM_OUTPUT_COLOR_FORMAT_YCBCR420 so long as the connector has legalized 420, otherwise error out. If the mode is not 420-capable, check with RGB as was previously always the case. Fixes: 47368ab437fd ("drm/display: hdmi: add generic mode_valid helper") Reviewed-by: Maxime Ripard Reviewed-by: Dmitry Baryshkov Signed-off-by: Nicolas Frattaroli --- drivers/gpu/drm/display/drm_hdmi_state_helper.c | 15 ++++++++++++++- 1 file changed, 14 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/display/drm_hdmi_state_helper.c b/drivers/gpu/= drm/display/drm_hdmi_state_helper.c index 954f8b2973fc..5cc30da30989 100644 --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c @@ -942,8 +942,21 @@ drm_hdmi_connector_mode_valid(struct drm_connector *co= nnector, const struct drm_display_mode *mode) { unsigned long long clock; + enum drm_output_color_format fmt; + + if (drm_mode_is_420_only(&connector->display_info, mode)) { + if (connector->ycbcr_420_allowed) + fmt =3D DRM_OUTPUT_COLOR_FORMAT_YCBCR420; + else + return MODE_NO_420; + } else if (drm_mode_is_420_also(&connector->display_info, mode) && + connector->ycbcr_420_allowed) { + fmt =3D DRM_OUTPUT_COLOR_FORMAT_YCBCR420; + } else { + fmt =3D DRM_OUTPUT_COLOR_FORMAT_RGB444; + } =20 - clock =3D drm_hdmi_compute_mode_clock(mode, 8, DRM_OUTPUT_COLOR_FORMAT_RG= B444); + clock =3D drm_hdmi_compute_mode_clock(mode, 8, fmt); if (!clock) return MODE_ERROR; =20 --=20 2.53.0