From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.9]) (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 1DC2A1119C; Wed, 14 Feb 2024 06:59:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=192.198.163.9 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707893956; cv=none; b=iBLBr7YbPeERzOSJ5aTGoofATEh7Mg5sQfIZRNvMSBQddvbqQCchXSK5ddaboHamOLj2yNBcu1r3AsNR4eLPaUuSE8RkHFl7uVonmhMpiQ6nRyOTRhEwKqaK7JhDiKh1J5WobZ5FSMJ4G8UsXSDUjCbnPOzJj+TVpKUDLcyZm7c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707893956; c=relaxed/simple; bh=NFdrGOtMllbEA7m7PeDgmPLNj3yRtazcQgFg1SMEcSE=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=uI8jjXfyJNYzT3dJgyoU5F40ly7Ie5adWW78s1a0Hsf6vsmPjlcZ0658gK8pATzHQGQ41f33MKeuhj4ec1dsuXINfDSKuNzzONY7CSWRj+NW0PZTEjkWHg0NZP5a9ZXTYgCtnGdqD7jWHlwXc7nu0h5wFDaNSaJQQyLkFrQimdA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com; spf=none smtp.mailfrom=linux.intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=gWbPeKK0; arc=none smtp.client-ip=192.198.163.9 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=linux.intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="gWbPeKK0" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1707893955; x=1739429955; h=message-id:date:mime-version:subject:to:cc:references: from:in-reply-to:content-transfer-encoding; bh=NFdrGOtMllbEA7m7PeDgmPLNj3yRtazcQgFg1SMEcSE=; b=gWbPeKK0X9rz/xB/iRb0WZAlyN08dVOMUTEx4W83PuyRyAPemyyuLehV IJRcaSFP8mDp+4G1L0ntg8caj8idyLG9ldtJh3Arnc08oyZUkSdeCVLXw ghLmjrj8RcNJIr66APnYItn/sVDnjQQqJ6YqvoSBiRSgK5Pjh/HyLUKZx Wlljiwjp9zxsrmXym+iZ7QD9oYWbk1QzqoHU5/8wcYzneA75VsSosekRJ 9M5VtFwr1ET8xtg5sDaIgzMBRm1/ThfuhpzzsH5jJJORmuU/csId/gbNd XKQEu1ttL775igfXmAmif38//F/bSoXMk9JljzSZM1RPLmkLaSvz1nJfy w==; X-IronPort-AV: E=McAfee;i="6600,9927,10982"; a="12646627" X-IronPort-AV: E=Sophos;i="6.06,159,1705392000"; d="scan'208";a="12646627" Received: from orviesa007.jf.intel.com ([10.64.159.147]) by fmvoesa103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Feb 2024 22:58:59 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.06,159,1705392000"; d="scan'208";a="3429746" Received: from jhogande-desk.fi.intel.com (HELO [10.237.72.164]) ([10.237.72.164]) by orviesa007.jf.intel.com with ESMTP; 13 Feb 2024 22:58:50 -0800 Message-ID: <93c77778-fbdc-4345-be8b-04959d1ce929@linux.intel.com> Date: Wed, 14 Feb 2024 08:58:48 +0200 Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v1] PCI / PM: Really allow runtime PM without callback functions To: Bjorn Helgaas , Raag Jadav Cc: bhelgaas@google.com, mika.westerberg@linux.intel.com, andriy.shevchenko@linux.intel.com, stanislaw.gruszka@linux.intel.com, lukas@wunner.de, rafael@kernel.org, ilpo.jarvinen@linux.intel.com, linux-pci@vger.kernel.org, linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org, sashal@kernel.org References: <20240213200648.GA1219964@bhelgaas> Content-Language: en-US From: Jarkko Nikula In-Reply-To: <20240213200648.GA1219964@bhelgaas> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi On 2/13/24 22:06, Bjorn Helgaas wrote: >> Debugged-by: Mika Westerberg > > Sounds like this resolves a problem report? Is there a URL we can > cite? If not, at least a mention of what the user-visible problem is? > > From the c5eb1190074c commit log, it sounds like maybe this allows > devices to be autosuspended when they previously could not be? > > Possibly this should have "Fixes: c5eb1190074c ("PCI / PM: Allow > runtime PM without callback functions")" since it sounds like it goes > with it? > I don't think there's known regression but my above commit wasn't complete. Autosuspending works without runtime PM callback as long as the driver has the PM callbacks structure set. For example the drivers/i2c/busses/i2c-i801.c has system suspend/resume callbacks. I tested this patch by hack-removing them and yes, autosuspend doesn't work without this patch. Raag and Mika noticed the issue when cleaning up empty runtime PM callbacks from an another driver which doesn't have any other PM callbacks.