From patchwork Fri Jul 12 09:32:23 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yijing Wang X-Patchwork-Id: 258724 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id B2A6B2C037A for ; Fri, 12 Jul 2013 19:37:40 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757489Ab3GLJgv (ORCPT ); Fri, 12 Jul 2013 05:36:51 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:51667 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757416Ab3GLJgu (ORCPT ); Fri, 12 Jul 2013 05:36:50 -0400 Received: from 172.24.2.119 (EHLO szxeml208-edg.china.huawei.com) ([172.24.2.119]) by szxrg02-dlp.huawei.com (MOS 4.3.4-GA FastPath queued) with ESMTP id BEM62220; Fri, 12 Jul 2013 17:36:45 +0800 (CST) Received: from SZXEML451-HUB.china.huawei.com (10.82.67.194) by szxeml208-edg.china.huawei.com (172.24.2.57) with Microsoft SMTP Server (TLS) id 14.1.323.7; Fri, 12 Jul 2013 17:36:41 +0800 Received: from localhost (10.135.76.69) by szxeml451-hub.china.huawei.com (10.82.67.194) with Microsoft SMTP Server id 14.1.323.7; Fri, 12 Jul 2013 17:36:40 +0800 From: Yijing Wang To: Bjorn Helgaas CC: , Don Dutile , Paul Bolle , , Rafael , Hanjun Guo , , Yijing Wang , Oliver Neukum , Gu Zheng Subject: [PATCH -v3 3/3] PCI, pciehp: use PCIe DSN to identify device change during suspend Date: Fri, 12 Jul 2013 17:32:23 +0800 Message-ID: <1373621543-54836-4-git-send-email-wangyijing@huawei.com> X-Mailer: git-send-email 1.7.11.msysgit.1 In-Reply-To: <1373621543-54836-1-git-send-email-wangyijing@huawei.com> References: <1373621543-54836-1-git-send-email-wangyijing@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.135.76.69] X-CFilter-Loop: Reflected Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org If device was removed from slot and reinsert a new device during suspend, pciehp can not identify the physical device change now. So the old driver .resume() method will be called for the new device, this is bad. If device support device serial number capability, we can identify this by DSN. So the reasonable way is first remove the old device, then enable the new device. Signed-off-by: Yijing Wang Cc: Paul Bolle Cc: "Rafael J. Wysocki" Cc: Oliver Neukum Cc: Gu Zheng Cc: linux-pci@vger.kernel.org --- drivers/pci/hotplug/pciehp_core.c | 45 +++++++++++++++++++++++++++++++++++++ 1 files changed, 45 insertions(+), 0 deletions(-) diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c index 7fe9dbd..bc47f8e 100644 --- a/drivers/pci/hotplug/pciehp_core.c +++ b/drivers/pci/hotplug/pciehp_core.c @@ -296,11 +296,38 @@ static int pciehp_suspend (struct pcie_device *dev) return 0; } +/* + * check the func 0 device serial number is changed, + * if device does not support device serial number, + * return false. + */ +static bool device_serial_number_changed(struct pci_bus *pbus) +{ + u64 old_dsn, new_dsn; + struct pci_dev *pdev; + + pdev = pci_get_slot(pbus, PCI_DEVFN(0, 0)); + if (!pdev) + return false; + + old_dsn = pdev->sn; + + /* get func 0 device serial number */ + new_dsn = pci_device_serial_number(pdev); + pci_dev_put(pdev); + + if (old_dsn != new_dsn) + return true; + + return false; +} + static int pciehp_resume (struct pcie_device *dev) { struct controller *ctrl; struct slot *slot; struct pci_bus *pbus = dev->port->subordinate; + int retval = 0; u8 status; ctrl = get_service_data(dev); @@ -315,6 +342,24 @@ static int pciehp_resume (struct pcie_device *dev) if (status) { if (list_empty(&pbus->devices)) pciehp_enable_slot(slot); + + if (device_serial_number_changed(pbus)) { + /* + * first power off slot, avoid the old driver + * .remove() method touch the new hardware + */ + if (POWER_CTRL(ctrl)) { + retval = pciehp_power_off_slot(slot); + if (retval) { + ctrl_err(ctrl, + "Issue of Slot Disable command failed\n"); + return 0; + } + msleep(1000); + pciehp_unconfigure_device(slot); + pciehp_enable_slot(slot); + } + } } else if (!list_empty(&pbus->devices)) { pciehp_disable_slot(slot); }