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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A45E9C4332F for ; Mon, 24 Jan 2022 22:06:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1579271AbiAXWFP (ORCPT ); Mon, 24 Jan 2022 17:05:15 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58590 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1457283AbiAXVzE (ORCPT ); Mon, 24 Jan 2022 16:55:04 -0500 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AAAC7C07E298; Mon, 24 Jan 2022 12:36:11 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 8C32661545; Mon, 24 Jan 2022 20:36:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5F4EEC340E5; Mon, 24 Jan 2022 20:36:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643056571; bh=b1kuycPtIuGNh9eiV5SiIWKNRLWLaFZgezxgdv7TYmM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=1ziLZFxRTzYJQS3pB/lezxpMtBuk/MygBG5z+vHXQ0+2LOzML+Vy5lKQKwAzZF2MD TK8m6Mur305T2RSgkUDxONenD8xPhTv2/iHY9SBWb2m6ITpbmdk2hXCBdHBR7JKNDh T2iXS5S0N2sJ3WcNglrQkmXwAzS/KlM8YyHCTOaI= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mika Westerberg , "Rafael J. Wysocki" , Sasha Levin Subject: [PATCH 5.15 528/846] thunderbolt: Runtime PM activate both ends of the device link Date: Mon, 24 Jan 2022 19:40:45 +0100 Message-Id: <20220124184119.221967598@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124184100.867127425@linuxfoundation.org> References: <20220124184100.867127425@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Mika Westerberg [ Upstream commit f3380cac0c0b3a6f49ab161e2a057c363962f48d ] If protocol tunnels are already up when the driver is loaded, for instance if the boot firmware implements connection manager of its own, runtime PM reference count of the consumer devices behind the tunnel might have been increased already before the device link is created but the supplier device runtime PM reference count is not. This leads to a situation where the supplier (the Thunderbolt driver) can runtime suspend even if it should not because the corresponding protocol tunnel needs to be up causing the devices to be removed from the corresponding native bus. Prevent this from happening by making both sides of the link runtime PM active briefly. The pm_runtime_put() for the consumer (PCIe root/downstream port, xHCI) then allows it to runtime suspend again but keeps the supplier runtime resumed the whole time it is runtime active. Signed-off-by: Mika Westerberg Reviewed-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/thunderbolt/acpi.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/drivers/thunderbolt/acpi.c b/drivers/thunderbolt/acpi.c index b67e72d5644b3..7c9597a339295 100644 --- a/drivers/thunderbolt/acpi.c +++ b/drivers/thunderbolt/acpi.c @@ -7,6 +7,7 @@ */ #include +#include #include "tb.h" @@ -74,8 +75,18 @@ static acpi_status tb_acpi_add_link(acpi_handle handle, u32 level, void *data, pci_pcie_type(pdev) == PCI_EXP_TYPE_DOWNSTREAM))) { const struct device_link *link; + /* + * Make them both active first to make sure the NHI does + * not runtime suspend before the consumer. The + * pm_runtime_put() below then allows the consumer to + * runtime suspend again (which then allows NHI runtime + * suspend too now that the device link is established). + */ + pm_runtime_get_sync(&pdev->dev); + link = device_link_add(&pdev->dev, &nhi->pdev->dev, DL_FLAG_AUTOREMOVE_SUPPLIER | + DL_FLAG_RPM_ACTIVE | DL_FLAG_PM_RUNTIME); if (link) { dev_dbg(&nhi->pdev->dev, "created link from %s\n", @@ -84,6 +95,8 @@ static acpi_status tb_acpi_add_link(acpi_handle handle, u32 level, void *data, dev_warn(&nhi->pdev->dev, "device link creation from %s failed\n", dev_name(&pdev->dev)); } + + pm_runtime_put(&pdev->dev); } out_put: -- 2.34.1