From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from szxga06-in.huawei.com (szxga06-in.huawei.com [45.249.212.32]) (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 1E9E32F4A for ; Fri, 12 Sep 2025 01:23:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=45.249.212.32 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757640193; cv=none; b=r0K/nQFmqEal3wG+RhEM/8ZrlAvBVuCWDMyaFB2eccYNfQcKiSa90j/BVTNpTjkrqFRoO1ybELhJrmtbuHsmUN6CBPyzH6Yruu4HzDkYMD/lcDOHAsgeIIpL6kSooqQoKGCGm2hC7rAzJ65YSBIgxThs4lkh8RbfXhRZxKDuhtM= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757640193; c=relaxed/simple; bh=PAWxn2kW/SU9pDXRX6sgoL7sS35UREsBql6go/aERCI=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=KEfu/k+nRO8HZo8WB3DEhxVmuuBrLh+phQ90SUTv1aLGdnxgArZKYUaoIPSjvbfl+tSq/5gkGCeeTRcZ1QMEzJ1ltWPRRXH004slMaJKWIZHaVQUqGaXe1q6GAYJb1zxtspMsYh2LuNcFPCWpbOO//sUKgZnbNylADhMZmPpjRI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com; spf=pass smtp.mailfrom=huawei.com; arc=none smtp.client-ip=45.249.212.32 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=huawei.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=huawei.com Received: from mail.maildlp.com (unknown [172.19.88.214]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4cNGt84VvWz3tZXQ; Fri, 12 Sep 2025 09:24:16 +0800 (CST) Received: from dggemv706-chm.china.huawei.com (unknown [10.3.19.33]) by mail.maildlp.com (Postfix) with ESMTPS id 3DBB81A016C; Fri, 12 Sep 2025 09:23:07 +0800 (CST) Received: from kwepemq100007.china.huawei.com (7.202.195.175) by dggemv706-chm.china.huawei.com (10.3.19.33) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 12 Sep 2025 09:23:06 +0800 Received: from [10.159.166.136] (10.159.166.136) by kwepemq100007.china.huawei.com (7.202.195.175) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Fri, 12 Sep 2025 09:23:06 +0800 Message-ID: <13b3f4d9-c8b4-445f-8f9e-a57a1fa2bbb5@huawei.com> Date: Fri, 12 Sep 2025 09:23:05 +0800 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 drm-dp 02/11] drm/hisilicon/hibmc: fix dp probabilistical detect errors after HPD irq To: Dmitry Baryshkov CC: , , , , , , , , , , , , , , , , References: <20250813094238.3722345-1-shiyongbang@huawei.com> <20250813094238.3722345-3-shiyongbang@huawei.com> <1dd93bb7-4f67-4b9b-8b6a-d7c5c77cf807@huawei.com> <8bbfd02f-138d-420c-b456-10d0c913f46e@huawei.com> From: Yongbang Shi In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: kwepems200002.china.huawei.com (7.221.188.68) To kwepemq100007.china.huawei.com (7.202.195.175) > On Thu, Sep 11, 2025 at 05:32:40PM +0800, Yongbang Shi wrote: >>> On Thu, Aug 14, 2025 at 08:19:41PM +0800, Yongbang Shi wrote: >>>>> On Wed, Aug 13, 2025 at 05:42:29PM +0800, Yongbang Shi wrote: >>>>>> From: Baihan Li >>>>>> >>>>>> The debouncing when HPD pulled out still remains sometimes, 200ms still can >>>>>> not ensure helper_detect() is correct. So add a flag to hold the sink >>>>>> status, and changed detect_ctx() functions by using flag to check status. >>>>> THis doesn't explain what is wrong with >>>>> drm_connector_helper_detect_from_ddc(). In the end, this function >>>>> doesn't use the HPD pin. >>>> I'm sorry about the misunderstanding. >>>> The issue is that after plugging or unplugging the monitor, the driver takes no action sometimes >>>> even though an interrupt is triggered. The root cause is that drm_connector_helper_detect_from_ddc() >>>> still returns connected status when the monitor is unplugged. >>>> And I will fix the way in the end. >>> Can you perform a normal DP detection: read DPCD and check that there is >>> a DPRX attached and that it's either non-branch device or it has one or >>> more sinks? >> I'm very sorry that I didn't get the last sentence's asking before. >> It's a non-branch device. We just connect a DP monitor. > Somebody might connect a different configuration than the one that you > are using. Okay, I can add the check drm_dp_is_branch() in the DP's detect_ctx() to intercept branch devices, is that good? Thanks, Baihan Li