From patchwork Mon Aug 2 09:14:13 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Aaron Ma X-Patchwork-Id: 1512332 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (no SPF record) smtp.mailfrom=lists.ubuntu.com (client-ip=91.189.94.19; helo=huckleberry.canonical.com; envelope-from=kernel-team-bounces@lists.ubuntu.com; receiver=) Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=canonical.com header.i=@canonical.com header.a=rsa-sha256 header.s=20210705 header.b=fvG5ljhk; dkim-atps=neutral Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4GdXPZ2yWyz9sWX; Mon, 2 Aug 2021 19:14:09 +1000 (AEST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.86_2) (envelope-from ) id 1mAU1K-0008LV-KI; Mon, 02 Aug 2021 09:14:02 +0000 Received: from smtp-relay-canonical-1.internal ([10.131.114.174] helo=smtp-relay-canonical-1.canonical.com) by huckleberry.canonical.com with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1mAU1G-0008Ks-U1 for kernel-team@lists.ubuntu.com; Mon, 02 Aug 2021 09:13:58 +0000 Received: from localhost.localdomain (unknown [222.129.38.241]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by smtp-relay-canonical-1.canonical.com (Postfix) with ESMTPSA id EBE783F07F for ; Mon, 2 Aug 2021 09:13:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=canonical.com; s=20210705; t=1627895638; bh=p5xBgS45V7B3t8ftTCM2TNvAsWSGs/eYj99xIDcwKOU=; h=From:To:Subject:Date:Message-Id:MIME-Version; b=fvG5ljhkChS6QuKgWZzSpJMqlVNOss1YgpnZAntVSpAWmlWbrUBYk9l9tEXZN1w0o Ul69EYwlqUTBQ5qHWD7NUGKC9zdvqc/NI+NQJCoicSq6LNSiA6df7NOcTFVkDe4BBM DsRPSZuHYddhW408lG5CDrvVtE6T6vsjL8mU0eCbT2i4NsWAGfYRtSzdbiH88s6YzE +7rZUfSKnjjJA83gF37YekLQys3da5Mi/XCz9+IbotXsUgrflptCIMfAXi9txJiqcT /T4Ejbwf/2iXxLSwSIf+BvfkQcvicRCqXLrGb6Fek9mUVkGG4kPEMYw1RYhOBazhBf Y+hgV/7GxTlrA== From: Aaron Ma To: kernel-team@lists.ubuntu.com Subject: [PATCH v2 0/1] [SRU][H] UBUNTU: SAUCE: Fix backlight control on Samsung 16727 panel Date: Mon, 2 Aug 2021 17:14:13 +0800 Message-Id: <20210802091414.9716-1-aaron.ma@canonical.com> X-Mailer: git-send-email 2.32.0 MIME-Version: 1.0 X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.20 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: "kernel-team" BugLink: https://bugs.launchpad.net/bugs/1930527 [Impact] Backlight can't be controlled on 5.11- version of kernel. [Fix] The panel needs DPCD to get control of backlight on 5.11- kernel. After 5.12 kernel introduced new Intel HDR backlight control, and it works well on this panel. Add quirk ID to enable DPCD on 5.11- kernel. Because upstream kernel already got a fix, this patch is not going to linus's tree. it's only for 5.11- stable kernel. This patch had been submitted to stable kernel twice, and got Acked by maintainer too. But still not applied. Regression: It adds ID to use DPCD AUX control, it should be safe as UBUNTU SAUCE patch for other panels. [Test] Vendor Verified on hardware, with this quirk backlight can be changed on 5.11 kernel. [Where problems could occur] The panel backlight may not be changed. Aaron Ma (1): UBUNTU: SAUCE: drm/i915: Force DPCD backlight mode for Samsung 16727 panel drivers/gpu/drm/drm_dp_helper.c | 1 + 1 file changed, 1 insertion(+) Acked-by: Tim Gardner