From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2792BC04FFE for ; Mon, 20 May 2024 11:49:02 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 36F6A10E067; Mon, 20 May 2024 11:49:01 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (1024-bit key; unprotected) header.d=linux.dev header.i=@linux.dev header.b="X2Di+fr3"; dkim-atps=neutral Received: from out-184.mta1.migadu.com (out-184.mta1.migadu.com [95.215.58.184]) by gabe.freedesktop.org (Postfix) with ESMTPS id B1CF310E067 for ; Mon, 20 May 2024 11:48:58 +0000 (UTC) X-Envelope-To: dmitry.baryshkov@linaro.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1716205735; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=z/2jIMHpQ5bz88ELVTIuNNb4NQxUzvaS8gU5mTaBGSc=; b=X2Di+fr32ouYtT2RQoCqmcywfTyjnqOfZwcx88Ts3so/uxK3xC6/dfwwU8kqtpQ9GDfEe1 bOFxOZB8nCsCcidXjxYqZRPcD/Mim24m42bsN5Bn4DsQH1OODajRu1CgSIdNCNmWFtTfgD VG0DdNhqelDu7nJcuYP0CBGQy1b0zik= X-Envelope-To: victor.liu@nxp.com X-Envelope-To: dri-devel@lists.freedesktop.org X-Envelope-To: linux-kernel@vger.kernel.org X-Envelope-To: andrzej.hajda@intel.com X-Envelope-To: neil.armstrong@linaro.org X-Envelope-To: rfoss@kernel.org X-Envelope-To: laurent.pinchart@ideasonboard.com X-Envelope-To: jonas@kwiboo.se X-Envelope-To: jernej.skrabec@gmail.com X-Envelope-To: maarten.lankhorst@linux.intel.com X-Envelope-To: mripard@kernel.org X-Envelope-To: tzimmermann@suse.de X-Envelope-To: airlied@gmail.com X-Envelope-To: daniel@ffwll.ch X-Envelope-To: biju.das.jz@bp.renesas.com X-Envelope-To: u.kleine-koenig@pengutronix.de X-Envelope-To: aford173@gmail.com X-Envelope-To: jani.nikula@intel.com X-Envelope-To: bli@bang-olufsen.dk Message-ID: Date: Mon, 20 May 2024 19:48:46 +0800 MIME-Version: 1.0 Subject: Re: [PATCH] drm/bridge: adv7511: Exit interrupt handling when necessary To: Dmitry Baryshkov Cc: Liu Ying , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, andrzej.hajda@intel.com, neil.armstrong@linaro.org, rfoss@kernel.org, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, daniel@ffwll.ch, biju.das.jz@bp.renesas.com, u.kleine-koenig@pengutronix.de, aford173@gmail.com, jani.nikula@intel.com, bli@bang-olufsen.dk References: <20240516101006.2388767-1-victor.liu@nxp.com> Content-Language: en-US, en-AU X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Sui Jingfeng In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Hi, On 5/20/24 19:13, Dmitry Baryshkov wrote: > On Mon, 20 May 2024 at 14:11, Sui Jingfeng wrote: >> >> Hi, >> >> On 5/20/24 06:11, Dmitry Baryshkov wrote: >>> On Thu, May 16, 2024 at 06:10:06PM +0800, Liu Ying wrote: >>>> Commit f3d9683346d6 ("drm/bridge: adv7511: Allow IRQ to share GPIO pins") >>>> fails to consider the case where adv7511->i2c_main->irq is zero, i.e., >>>> no interrupt requested at all. >>>> >>>> Without interrupt, adv7511_wait_for_edid() could return -EIO sometimes, >>>> because it polls adv7511->edid_read flag by calling adv7511_irq_process() >>>> a few times, but adv7511_irq_process() happens to refuse to handle >>>> interrupt by returning -ENODATA. Hence, EDID retrieval fails randomly. >>>> >>>> Fix the issue by checking adv7511->i2c_main->irq before exiting interrupt >>>> handling from adv7511_irq_process(). >>>> >>>> Fixes: f3d9683346d6 ("drm/bridge: adv7511: Allow IRQ to share GPIO pins") >>>> Signed-off-by: Liu Ying >>>> --- >>>> drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 3 ++- >>>> 1 file changed, 2 insertions(+), 1 deletion(-) >>>> >>>> diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c >>>> index 6089b0bb9321..2074fa3c1b7b 100644 >>>> --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c >>>> +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c >>>> @@ -479,7 +479,8 @@ static int adv7511_irq_process(struct adv7511 *adv7511, bool process_hpd) >>>> return ret; >>>> >>>> /* If there is no IRQ to handle, exit indicating no IRQ data */ >>>> - if (!(irq0 & (ADV7511_INT0_HPD | ADV7511_INT0_EDID_READY)) && >>>> + if (adv7511->i2c_main->irq && >>>> + !(irq0 & (ADV7511_INT0_HPD | ADV7511_INT0_EDID_READY)) && >>>> !(irq1 & ADV7511_INT1_DDC_ERROR)) >>>> return -ENODATA; >>> >>> I think it might be better to handle -ENODATA in adv7511_wait_for_edid() >>> instead. WDYT? >>> >> >> I think this is may deserve another patch. > > My point is that the IRQ handler is fine to remove -ENODATA here, [...] > there is no pending IRQ that can be handled. But there may has other things need to do in the adv7511_irq_process() function. So instead of continuing > the execution when we know that IRQ bits are not set, Even when IRQ bits are not set, it just means that there is no HPD and no EDID ready-to-read signal. HDMI CEC interrupts still need to process. it's better to > ignore -ENODATA in the calling code and go on with msleep(). > So, It's confusing to ignore the -ENODATA here. -- Best regards Sui