From mboxrd@z Thu Jan 1 00:00:00 1970 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 473B033D6D7 for ; Mon, 8 Jun 2026 11:19:41 +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=1780917582; cv=pass; b=hvkxTQESEQbV4f8kaP4s02dlIiH7+J/p1f8mC5ev1MMTe6JQPBVbZKatc1wCMIeat1PRiRwrI9RSNU39pfmvAF7raT2Elv6l18o3WP3zzTnSPV2CVJ7Qy6KIh+5rcEv5MZHK+w+9PDy+vrumNnDUZgPk2DEEeaL0Oduedgm9TfU= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780917582; c=relaxed/simple; bh=/U61PxC13uPodbsy3tKf/P60yr7fljtD0+C7EbtoAjY=; h=From:Subject:Date:Message-Id:MIME-Version:Content-Type:To:Cc; b=UjkClKOoDt7HRR6E5hWNVmzsKA3lNHLFHp1yOKb8XxnA23454Cp0OsKBN5Saryh/N3p1Kgosf8g6IiQB5Om8da7IQ0jEMS+w3dHPfqMCb8HRfHEamrxSFcW5TYcG549krxQUmDUgzDjRvH88JgZ0XylMElStTuaI+kvF5y6IzMI= 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=dG/Nf8DA; 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="dG/Nf8DA" ARC-Seal: i=1; a=rsa-sha256; t=1780917564; cv=none; d=zohomail.com; s=zohoarc; b=SxhJTpgpZcTVr+jbFDgHa1rcndzwec1/U+Q8LVcq9hn3c7GQJR6d0NXhhF5yXX3Meo+S3lUEtBvyxtXb2nIbnr7bK3pYSOfwRLSgcF5phirwNJFTpSIQkN8F4HAPTQGdSAukt3pvr414MZavRTbShu+NPHNAxFyL6KFJvwBuShA= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1780917564; h=Content-Type:Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=w95v8rmypZzUecGHeRmBiKIIuhZ1fsqWje5Fpue/L1M=; b=QofVtK8uINWdohXqpSVnAu6oN0FXSYmQQZ54yws4OKB7RRPfgQxxyV9kS/mkvSz1Hv/ulf2x8f9AbWvUCjWA2NIp6m05AjY2WmZ0u0N9npFF6hoV0omL/waj29cpIQDhFvLQeoxtwIjIdZCXuv9jnEJpnOCSHmMAHm5+d1/6bwI= 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=1780917564; s=zohomail; d=collabora.com; i=nicolas.frattaroli@collabora.com; h=From:From:Subject:Subject:Date:Date:Message-Id:Message-Id:MIME-Version:Content-Type:Content-Transfer-Encoding:To:To:Cc:Cc:Reply-To; bh=w95v8rmypZzUecGHeRmBiKIIuhZ1fsqWje5Fpue/L1M=; b=dG/Nf8DAIw4v4qK1H4AX6CUqLurxf5MLESWaQ8CyFb2et6bceSOfRqrIVBsnMj5O iQ433VlDXXE/AJK1/nd/17Cc30SNqcU6U9CwNLtLxmiEnbkZ+YvKss+N1DnRB2c42RM abG/q559wUnGXpVfG/yCJBupAUkb4bBwZbzvTjUM= Received: by mx.zohomail.com with SMTPS id 1780917562612833.0652412976524; Mon, 8 Jun 2026 04:19:22 -0700 (PDT) From: Nicolas Frattaroli Subject: [PATCH 0/2] Make HDMI state helpers handle odd max bpc requests Date: Mon, 08 Jun 2026 13:19:06 +0200 Message-Id: <20260608-hdmi-max-bpc-fix-v1-0-6e8dcebc7274@collabora.com> 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: 7bit X-B4-Tracking: v=1; b=H4sIAAAAAAAC/y2NTQ6CMBCFr9LM2omFGkCuYljQdpQxKZS2GBLC3 a3C6uV7eT8bRApMEVqxQaAPR57GDMVFgBn68UXINjOUsqxkJRscrGN0/YraG3zyirVUsrjXlWr UDXLNB8r2f/LRHRwX/SaTfjtnItC85K90xED3kdBMznFqhQ0OE/vrqdDt+xe5A4orpwAAAA== X-Change-ID: 20260608-hdmi-max-bpc-fix-703019763834 To: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter , Dmitry Baryshkov Cc: dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, kernel@collabora.com, Nicolas Frattaroli X-Mailer: b4 0.15.2 With the "max bpc" KMS connector property, userspace can arbitrarily restrict the upper end of the bits-per-component range. This is fine and good, except the HDMI state helpers never considered that max_bpc could be influenced by a userspace setting, so assumed it'll always be an even value from the HDMI standards. This, unfortunately, is not the world we live in anymore. Patch 1 corrects sink_supports_format_bpc to return false on BPCs outside of what HDMI allows. Patch 2 then corrects handling of odd-numbered max bpcs by rounding the loop start value down to an even number instead. It also adds a KUnit test to make sure nobody breaks this again in the future. Signed-off-by: Nicolas Frattaroli --- Nicolas Frattaroli (2): drm/display: hdmi: Only allow BPC values of 8, 10, 12 and 16 drm/display: hdmi: Round odd max_bpc down to even numbers drivers/gpu/drm/display/drm_hdmi_state_helper.c | 12 +++- drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 71 ++++++++++++++++++++++ 2 files changed, 82 insertions(+), 1 deletion(-) --- base-commit: be3e81d74654555fff2779d78848267bd50dcf51 change-id: 20260608-hdmi-max-bpc-fix-703019763834 Best regards, -- Nicolas Frattaroli