From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-182.mta0.migadu.com (out-182.mta0.migadu.com [91.218.175.182]) (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 5DCC11DE2B4 for ; Tue, 1 Apr 2025 18:18:57 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743531539; cv=none; b=e2nL5Dd1ddNOEoiWewj5MQ1ALBxerA8XcDCr8uZCoNyU86DQSIC3zkP63rqtLMozN7oghJ3+oqh3aF7VW4EsbBPfUHt+YutXnV+8vzP6hkl3/zB76qSmsJXmqIFL2dUHn5abL4Cj8MQjd6SPzK73cDWvXet3d6k1aEo7IPOWfJY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1743531539; c=relaxed/simple; bh=k4nbEj2HOrkVKd3meibvEKz8GTVSNgISM5g0cAlbbB0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=R/nrNFVH3ijSs6mXfN47+s+QmEoSXvOhvM3PY73bYZIwnr4mUh6GZrDS27N1Vh1hcCS4kZDZmQt1UFoKK3qVDDjmri8pF7D+2bUpucpyYWO7MXk5gsM5sEgota/W5UGWn3d33vDBCbEJK687pxeGOW6sSWaubFDMHIP0+iS8hMc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=craftyguy.net; spf=pass smtp.mailfrom=craftyguy.net; dkim=pass (2048-bit key) header.d=craftyguy.net header.i=@craftyguy.net header.b=GZg9ADIz; arc=none smtp.client-ip=91.218.175.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=craftyguy.net Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=craftyguy.net Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=craftyguy.net header.i=@craftyguy.net header.b="GZg9ADIz" Message-ID: <7e287401-98c4-413f-8108-134d5e43d279@craftyguy.net> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=craftyguy.net; s=key1; t=1743531535; 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=mPDdthZvOKQegQtqGLkhrEwgHRPScxP/qocRmzW8nbA=; b=GZg9ADIzt1neDQckUX7aNRGvlukEVYj56hWCAdR/hMVBomhLpwnaXTdbC2h1PND/4irDiT HjDw76E7lycsAF1KvO15jn3uO8RxYSOvmudpU1CJ76omexpvW87QzIEZKZtGegljFnNoks KbBogy6tvjI2T236d/wQb/SpZM1atC+rwW3D6F5ZkQQ9YGvplzC9uYSVWV48Gt5kb7cu9r /pzOcRrTRi63W0VdsEuzQqIRFu9F2n/YTJGZS/3SjRwDN8/4RTKyUL/neRC1NYGNz3ddb3 LzeDonS9LtBQ9zGLG0rY6CCOLIjH23PG2tugNLWr4HsxPfagfBsi4KBqf6UgbQ== Date: Tue, 1 Apr 2025 11:18:49 -0700 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH] soc: qcom: pmic_glink_altmode: fix spurious DP hotplug events To: Johan Hovold Cc: Johan Hovold , Bjorn Andersson , Konrad Dybcio , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org References: <20250324132448.6134-1-johan+linaro@kernel.org> Content-Language: en-US X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Clayton Craft In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Migadu-Flow: FLOW_OUT On 3/26/25 07:43, Johan Hovold wrote: > On Tue, Mar 25, 2025 at 09:32:10AM +0100, Johan Hovold wrote: >> On Mon, Mar 24, 2025 at 10:05:44AM -0700, Clayton Craft wrote: >>> On 3/24/25 06:24, Johan Hovold wrote: >>>> The PMIC GLINK driver is currently generating DisplayPort hotplug >>>> notifications whenever something is connected to (or disconnected from) >>>> a port regardless of the type of notification sent by the firmware. >>>> >>>> These notifications are forwarded to user space by the DRM subsystem as >>>> connector "change" uevents: >> >>>> --- >>>> >>>> Clayton reported seeing display flickering with recent RC kernels, which >>>> may possibly be related to these spurious events being generated with >>>> even greater frequency. >>>> >>>> That still remains to be fully understood, but the spurious events, that >>>> on the X13s are generated every 90 seconds, should be fixed either way. >>> >>> When a display/dock (which has ethernet) is connected, I see this >>> hotplug change event 2 times (every 30 seconds) which I think you said >>> this is expected now? >> >> I didn't realise you were also using a display/dock. Bjorn mentioned >> that he has noticed issues with one of his monitors (e.g. built-in hub >> reenumerating repeatedly iirc) which may be related. Sorry for the confusion, let me clarify: The original issue I reported to you on IRC was *without* a dock/external display attached, only a PD adapter was attached. With your patch, I no longer see these drm hotplug events in this scenario. After confirming that your patch resolved the spurious hotplug events when using a PD charger, I connected a dock+external display to see if the patch caused any regressions there for me. It was here that I noticed a periodic hotplug event firing 2 times every 30 seconds was still showing up. I don't know if this is expected or not, I've never noticed it before because I wasn't monitoring udev events. >> Just so I understand you correctly here, you're no longer seeing the >> repeated uevents with this patch? Both when using a dock and when using >> a charger directly? With PD charger only: no more spurious hotplug events firing With dock+external displauy: 2x hotplug events every 30s. >> >> Did it help with the display flickering too? Was that only on the >> external display? The flickering was only on the internal display, and your patch here seems to have resolved that. -Clayton