From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9A2CACA5FD7 for ; Wed, 21 Jan 2026 14:46:28 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 2D89210E7FC; Wed, 21 Jan 2026 14:46:28 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=collabora.com header.i=nicolas.frattaroli@collabora.com header.b="BBA3G30g"; dkim-atps=neutral Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3AEC310E801; Wed, 21 Jan 2026 14:46:27 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; t=1769006780; cv=none; d=zohomail.com; s=zohoarc; b=e0A4bW9Bg//mH1TE8GfuAwqfayUGCpTByz8IEEaPpwXzBquMDVy0nh5DH51xbXKy5rmPwQH662AUdtZWghBgIouKZ/a4t5OcyMy6SRhKH7RF5w3XFXv3u1InZKhbzjnQuvfGp2x8L+/2NpFL+8gNDT5cyce1xYSb7IQm4Ny9WbY= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1769006780; 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=w+BU3yZcnZLVUl/l+ViGJZdk5XsNHMsU7ReIC8wTppQ=; b=UCX3Sl2AfKRLsoHrzKby2mB6kAlz8z7DLkyY2+qpryszgxTq5gKYjjN3N8LBgdeXs63ZR2XJQBp3n2w467z1PwweHayc0MWK7bkFJ9fn9HSueTfjNeCiVs/l9hf5cP827z+M+CJHOUZJTNxfEV1ZSeCjTJnKQeqlBIrdinhwmuc= 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=1769006780; 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=w+BU3yZcnZLVUl/l+ViGJZdk5XsNHMsU7ReIC8wTppQ=; b=BBA3G30gz/faVkMIqxUCEfIPk4lJkyDvkZggDeRxsF+FnBk5WUiwMEHQo9huuyiy h6tP6sZzmVJFb1mG3J6aljLWPNV+RxGUhRefiXBWZD8OZq9a6NJCzfHDr0Z9td7/Ahu PhVSsOrPoBTnnbM0fkZMh4rytu6Lyv0rcJGVWJY0= Received: by mx.zohomail.com with SMTPS id 1769006778497255.4881577685843; Wed, 21 Jan 2026 06:46:18 -0800 (PST) From: Nicolas Frattaroli Date: Wed, 21 Jan 2026 15:45:13 +0100 Subject: [PATCH v7 06/22] drm/display: hdmi-state-helper: Try subsampling in mode_valid MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260121-color-format-v7-6-ef790dae780c@collabora.com> References: <20260121-color-format-v7-0-ef790dae780c@collabora.com> In-Reply-To: <20260121-color-format-v7-0-ef790dae780c@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 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 X-Mailer: b4 0.14.3 X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" 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 HDMI_COLORSPACE_YUV420 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") 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 1ea3b9c93aa5..ceabfdb30f7a 100644 --- a/drivers/gpu/drm/display/drm_hdmi_state_helper.c +++ b/drivers/gpu/drm/display/drm_hdmi_state_helper.c @@ -898,8 +898,21 @@ drm_hdmi_connector_mode_valid(struct drm_connector *connector, const struct drm_display_mode *mode) { unsigned long long clock; + enum hdmi_colorspace fmt; + + if (drm_mode_is_420_only(&connector->display_info, mode)) { + if (connector->ycbcr_420_allowed) + fmt = HDMI_COLORSPACE_YUV420; + else + return MODE_NO_420; + } else if (drm_mode_is_420_also(&connector->display_info, mode) && + connector->ycbcr_420_allowed) { + fmt = HDMI_COLORSPACE_YUV420; + } else { + fmt = HDMI_COLORSPACE_RGB; + } - clock = drm_hdmi_compute_mode_clock(mode, 8, HDMI_COLORSPACE_RGB); + clock = drm_hdmi_compute_mode_clock(mode, 8, fmt); if (!clock) return MODE_ERROR; -- 2.52.0