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 30CB8236424 for ; Thu, 27 Feb 2025 13:46:21 +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=1740663985; cv=none; b=nVz99KPyI0fbiiuVD7WyDChOaQMxOkQ+L2kU6VP8Jjfx/611eTMyz5/iy6mLvi87+dtir01kOqslL4wNAtORj68/I80iYZWxE30vt6IeELzDI0xzgUXps4n/vvIou/KJQPF8hRCa3+vcOx77aipfXlvyT1ysX2OTpnHKGfGZgu4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740663985; c=relaxed/simple; bh=wxhkOkgTSf9OunK+3Dj7PGjTKndXKiFfjNSpuF/go/c=; h=Message-ID:Date:MIME-Version:Subject:To:CC:References:From: In-Reply-To:Content-Type; b=DwJohx0JXUHzh+0Fd/Dv1tDd1QSl0/obxJE2aIHPsqP7dgDwN3zJwTfiA0bMNf6wLOXUetzSyZ24gTn0QyiNBdV4F6cNgI7KN5noQ89Y+jTrI3PFokFUZbrIWkONsUV4HbMabWtgQjEK2cuJ5XjLkos0Ts1/2YBS5OWKLhzaBtg= 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 [172.19.163.17]) by szxga06-in.huawei.com (SkyGuard) with ESMTP id 4Z3Xgn5FfjzpkHP; Thu, 27 Feb 2025 21:46:45 +0800 (CST) Received: from kwepemd500013.china.huawei.com (unknown [7.221.188.12]) by mail.maildlp.com (Postfix) with ESMTPS id 41CD91A0188; Thu, 27 Feb 2025 21:46:13 +0800 (CST) Received: from [10.159.166.136] (10.159.166.136) by kwepemd500013.china.huawei.com (7.221.188.12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.34; Thu, 27 Feb 2025 21:46:11 +0800 Message-ID: Date: Thu, 27 Feb 2025 21:46:10 +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 v3 drm-dp 7/8] drm/hisilicon/hibmc: Enable this hot plug detect of irq feature To: Dmitry Baryshkov CC: , , , , , , , , , , , , , , , , References: <20250222025102.1519798-1-shiyongbang@huawei.com> <20250222025102.1519798-8-shiyongbang@huawei.com> <6jx5ldpidy2ycrqognfiv5ttqr5ia4dtbryta3kc2mkndrvvgo@qzuakucz765k> <6634386b-afc1-4e31-a2f4-9c1afed2d1d8@huawei.com> <5af62fa9-e71b-412f-8640-502f03fcaa52@huawei.com> From: Yongbang Shi In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: dggems703-chm.china.huawei.com (10.3.19.180) To kwepemd500013.china.huawei.com (7.221.188.12) > On Tue, Feb 25, 2025 at 09:57:17PM +0800, Yongbang Shi wrote: >>> On Mon, 24 Feb 2025 at 16:03, Yongbang Shi wrote: >>>>> On Sat, Feb 22, 2025 at 06:35:48PM +0800, Yongbang Shi wrote: >>>>>>>> +static int hibmc_dp_hpd_event(struct drm_client_dev *client) >>>>>>>> +{ >>>>>>>> + struct hibmc_dp *dp = container_of(client, struct hibmc_dp, client); >>>>>>>> + struct hibmc_drm_private *priv = to_hibmc_drm_private(dp->drm_dev); >>>>>>>> + struct drm_display_mode *mode = &priv->crtc.state->adjusted_mode; >>>>>>>> + int ret; >>>>>>>> + >>>>>>>> + if (dp->hpd_status) { >>>>>>>> + hibmc_dp_hpd_cfg(&priv->dp); >>>>>>>> + ret = hibmc_dp_prepare(dp, mode); >>>>>>>> + if (ret) >>>>>>>> + return ret; >>>>>>>> + >>>>>>>> + hibmc_dp_display_en(dp, true); >>>>>>>> + } else { >>>>>>>> + hibmc_dp_display_en(dp, false); >>>>>>>> + hibmc_dp_reset_link(&priv->dp); >>>>>>>> + } >>>>>>> If I understand this correctly, you are using a separate drm_client to >>>>>>> enable and disable the link & display. Why is it necessary? Existing >>>>>>> drm_clients and userspace compositors use drm framework, they should be >>>>>>> able to turn the display on and off as required. >>>>>>> >>>>>> Thanks for your asking, there are cfg/reset process when the connector 's pluging in/out. >>>>>> We want to cfg DP registers again when the connector changes. Not only dp link training, but also cfg >>>>>> the different video modes into DP registers. >>>>> Why? The link training and mode programming should happen during >>>>> pre_enable / enable stage (legacy or atomic). >>>> Hi Dmitry, >>>> >>>> Right, that's what I'm curious about. It won't call encoder enble/disable functions when I triggered HPD. >>>> And I'm sure the drm_connector_helper_hpd_irq_event() is called. So I add a drm_client for it.I >>> It should be userspace, who triggers the enable/disable (or it should >>> be the in-kernel fbdev / fbcon, which interface through the generic >>> drm_fbdev client). >> Right, I knew it. When I insmode my driver firstly (or restart display service), it will call disable, modeset and enable, >> by user, but it won't call when HPD triggered . > - Is HPD even properly delivered to userspace? What kind of compsitor > are you using? Is .detect working properly and reporting a correct > plug-in state? Thanks for your answering. I'm not very good understanding about userspace in framework. In my opinion, when I call this drm_connector_helper_hpd_irq_event(), the HPD will deliver to userspace. I use Xorg, and the display service is GDM. The .detect is called and the getting modes info is correct. I find that it would only trigger(disable, modeset and enable), when I changed resolutions, restart display service and insmod driver.