From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender4-op-o12.zoho.com (sender4-op-o12.zoho.com [136.143.188.12]) (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 A8FEF288C2D; Sat, 25 Jul 2026 17:36:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.12 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785000997; cv=pass; b=VxySH7POgZaIiOIUXGb2qivfw9TdfEMLenZPFN3OX0r+wJ6QIXDS78eNPGbJlvbBC/nBiopTl+vdR+gtc6B39VtpjyGZUIHmKkKPoT2kVpYP0j7KYtpXCVy5q/6Sf947GTKiwEIVzi7UgXUsReKJoDrrkbByA+q+HupGIdR3HTg= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785000997; c=relaxed/simple; bh=aaT4bSz5HqqnTrLzg36MqwkeRkeee05kQBWMOuFMa9A=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=P2ZQm99Si8SiDgaa8x2OzjX8uFU0TbWbXn52Vc5L4QdSL+vattXdlB88PxZfOIbE6cu+xauvnicUH65Qlwj7F8dTKPXbPJIvnZLahzObAkU16df7c9OQfxSeRfdg4RDIdS9HJLHIygtivZYZ6DVmwVPpozI3cxRAN2WmI0uOoyM= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ziyao.cc; spf=pass smtp.mailfrom=ziyao.cc; dkim=pass (1024-bit key) header.d=ziyao.cc header.i=me@ziyao.cc header.b=czLI0mj3; arc=pass smtp.client-ip=136.143.188.12 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=ziyao.cc Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ziyao.cc Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ziyao.cc header.i=me@ziyao.cc header.b="czLI0mj3" ARC-Seal: i=1; a=rsa-sha256; t=1785000972; cv=none; d=zohomail.com; s=zohoarc; b=RYuLiCNK/wLM+A1AL+pi7reeRfYUqTvJfzNwaUYFST6oGvWU0r/XmZYJ/AtLCufWD6zOqco+OFwVexiNNKiyMNzMFgDeBMEwOCBMXk+KBjfM98jtxol281qb2kUzhPB/xFTwIi+h+B8NMMyUPokv4m68Gj14JnfE032O2Xpnky0= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1785000972; h=Content-Type:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=WKq3a9nQc3N0aKZSTpXVKdyLOSqPpQF428qAw79wyQs=; b=OiaSQ4bVUWFXJWQ32dSTu6iCPU20ymm1qO3bfgbiP9u6Bi8KI0imxjdqCz+Hk8fiByK2lNEpucjp1o3obfikW4XaMcqcF6Ln5hFd9kUdJR51XAQ2IXAtOafnhc9geB5wNwFkd1YCV4jIfDWQmZrL1ZwW6f2fCx0UF4cqsDMmjVE= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=ziyao.cc; spf=pass smtp.mailfrom=me@ziyao.cc; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1785000972; s=zmail; d=ziyao.cc; i=me@ziyao.cc; h=Date:Date:From:From:To:To:Cc:Cc:Subject:Subject:Message-ID:MIME-Version:Content-Type:In-Reply-To:Message-Id:Reply-To; bh=WKq3a9nQc3N0aKZSTpXVKdyLOSqPpQF428qAw79wyQs=; b=czLI0mj30hc4LWFO1Tueq8WRo+KJA6tmUGbitGWug78ATEAVdjpHjgTshFYnnnL9 GffR3iyKrM9FoDvcOWcWJG0r2mI3vU3ty77K1tdQXpFVb0AcB7HIMqFqfQwjkjk//mX sv18y8/olrNMmEFss6B0Go/gNmPlPX0cdjmvv8ao= Received: by mx.zohomail.com with SMTPS id 1785000966591653.2956125819782; Sat, 25 Jul 2026 10:36:06 -0700 (PDT) Date: Sat, 25 Jul 2026 17:35:57 +0000 From: Yao Zi To: Zixing Liu , linux-kernel@vger.kernel.org, Yao Zi , Jianmin Lv , WANG Xuerui , Huacai Chen Cc: Kexy Biscuit , Mingcong Bai , loongarch@lists.linux.dev, stable@vger.kernel.org, Yao Zi Subject: Re: [PATCH v2] platform/loongarch: laptop: explicitly reset the bl_powered state when resuming Message-ID: References: <20260723121840.1120953-2-liushuyu@aosc.io> 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=us-ascii Content-Disposition: inline In-Reply-To: <20260723121840.1120953-2-liushuyu@aosc.io> X-Zoho-Virus-Status: 1 X-Zoho-AV-Stamp: zmail-av-0.2.10.1.5.2/284.966.17 X-ZohoMailClient: External On Thu, Jul 23, 2026 at 08:18:39PM +0800, Zixing Liu wrote: > On EAECIS NL60R with EC firmware version 1.11, resuming from S3 has a very > high chance (>= 90%) of causing the EC to lose the previous backlight > power state. When this happens, the laptop resumes normally from S3, but > the backlight remains off (when shining on the screen with a flash light, > we can see the screen contents are updating normally). > > Since there is no generic way to query the EC's backlight state on > Loongson laptop platforms, assume the worst-case scenario and restart the > backlight power inside the kernel each time the system resumes. > > Cc: stable@vger.kernel.org > Fixes: 53c762b47f72 ("platform/loongarch: laptop: Add backlight power control support") > Signed-off-by: Zixing Liu > --- > Changes in v2: > - Move bl_powered reset logic to loongson_hotkey_suspend. > - Link to v1: https://lore.kernel.org/loongarch/20260722044457.1333404-1-liushuyu@aosc.io/ Again on my TongFang L860-T2 3A5000 laptop, no regression is observed. Tested-by: Yao Zi Best regards. Yao Zi