From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> Jarod Wilson reports that the expresscard hotplug setup doesn't work on HP ZBook G2. The problem turns out to be the ACPI-based "slot detection" code called from pciehp_probe() which tries to use some questionable heuristics based on what ACPI objects are present for the PCIe port device at hand to figure out whether or not to register a hotplug slot for that port. That code is used if there is at least one PCIe port having an ACPI device configuration object related to hotplug (such as _EJ0 or _RMV) and the Thunderbolt port on the affected machine has _RMV. Of course, Thunderbolt and PCIe native hotplug need not be mutually exclusive (as they aren't on the machine in question), so that rule is simply incorrect. Moreover, the ACPI-based "slot detection" check does not add any value if pciehp_probe() is called at all and the service type of the device object it has been called for is PCIE_PORT_SERVICE_HP, because PCIe hotplug services are only registered if the _OSC handshake in acpi_pci_root_add() allows the kernel to control the PCIe native hotplug feature. No more checks need to be carried out to decide whether or not to register a native PCIe hotlug slot in that case. For the above reasons, make pciehp_probe() check if it has been called for the right service type and drop the pointless ACPI-based "slot detection" check from it. Also remove the entire code whose only user is that check (the entire pciehp_acpi.c file goes away as a result) and drop function headers related to it from the internal PCIeHP header file. Link: http://marc.info/?t=143163219300002&r=1&w=2 Link: https://bugzilla.kernel.org/show_bug.cgi?id=98581 Reported-by: Jarod Wilson <jarod@xxxxxxxxxx> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> --- Bjorn, that's -stable material I think. It should be applicable at least since commit 5ba113f7c4fb (PCI: acpiphp: Handle PCIe ports without native hotplug capability) that was shipped in 3.10. Thanks! --- drivers/pci/hotplug/pciehp.h | 17 ---- drivers/pci/hotplug/pciehp_acpi.c | 137 -------------------------------------- drivers/pci/hotplug/pciehp_core.c | 10 -- 3 files changed, 3 insertions(+), 161 deletions(-) Index: linux-pm/drivers/pci/hotplug/pciehp_core.c =================================================================== --- linux-pm.orig/drivers/pci/hotplug/pciehp_core.c +++ linux-pm/drivers/pci/hotplug/pciehp_core.c @@ -248,12 +248,9 @@ static int pciehp_probe(struct pcie_devi struct slot *slot; u8 occupied, poweron; - if (pciehp_force) - dev_info(&dev->device, - "Bypassing BIOS check for pciehp use on %s\n", - pci_name(dev->port)); - else if (pciehp_acpi_slot_detection_check(dev->port)) - goto err_out_none; + /* If this is not a "hotplug" service, we have no business here. */ + if (dev->service != PCIE_PORT_SERVICE_HP) + return -ENODEV; if (!dev->port->subordinate) { /* Can happen if we run out of bus numbers during probe */ @@ -366,7 +363,6 @@ static int __init pcied_init(void) { int retval = 0; - pciehp_firmware_init(); retval = pcie_port_service_register(&hpdriver_portdrv); dbg("pcie_port_service_register = %d\n", retval); info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); Index: linux-pm/drivers/pci/hotplug/pciehp_acpi.c =================================================================== --- linux-pm.orig/drivers/pci/hotplug/pciehp_acpi.c +++ /dev/null @@ -1,137 +0,0 @@ -/* - * ACPI related functions for PCI Express Hot Plug driver. - * - * Copyright (C) 2008 Kenji Kaneshige - * Copyright (C) 2008 Fujitsu Limited. - * - * All rights reserved. - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or (at - * your option) any later version. - * - * This program is distributed in the hope that it will be useful, but - * WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or - * NON INFRINGEMENT. See the GNU General Public License for more - * details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - * - */ - -#include <linux/acpi.h> -#include <linux/pci.h> -#include <linux/pci_hotplug.h> -#include <linux/slab.h> -#include <linux/module.h> -#include "pciehp.h" - -#define PCIEHP_DETECT_PCIE (0) -#define PCIEHP_DETECT_ACPI (1) -#define PCIEHP_DETECT_AUTO (2) -#define PCIEHP_DETECT_DEFAULT PCIEHP_DETECT_AUTO - -struct dummy_slot { - u32 number; - struct list_head list; -}; - -static int slot_detection_mode; -static char *pciehp_detect_mode; -module_param(pciehp_detect_mode, charp, 0444); -MODULE_PARM_DESC(pciehp_detect_mode, - "Slot detection mode: pcie, acpi, auto\n" - " pcie - Use PCIe based slot detection\n" - " acpi - Use ACPI for slot detection\n" - " auto(default) - Auto select mode. Use acpi option if duplicate\n" - " slot ids are found. Otherwise, use pcie option\n"); - -int pciehp_acpi_slot_detection_check(struct pci_dev *dev) -{ - if (slot_detection_mode != PCIEHP_DETECT_ACPI) - return 0; - if (acpi_pci_detect_ejectable(ACPI_HANDLE(&dev->dev))) - return 0; - return -ENODEV; -} - -static int __init parse_detect_mode(void) -{ - if (!pciehp_detect_mode) - return PCIEHP_DETECT_DEFAULT; - if (!strcmp(pciehp_detect_mode, "pcie")) - return PCIEHP_DETECT_PCIE; - if (!strcmp(pciehp_detect_mode, "acpi")) - return PCIEHP_DETECT_ACPI; - if (!strcmp(pciehp_detect_mode, "auto")) - return PCIEHP_DETECT_AUTO; - warn("bad specifier '%s' for pciehp_detect_mode. Use default\n", - pciehp_detect_mode); - return PCIEHP_DETECT_DEFAULT; -} - -static int __initdata dup_slot_id; -static int __initdata acpi_slot_detected; -static struct list_head __initdata dummy_slots = LIST_HEAD_INIT(dummy_slots); - -/* Dummy driver for duplicate name detection */ -static int __init dummy_probe(struct pcie_device *dev) -{ - u32 slot_cap; - acpi_handle handle; - struct dummy_slot *slot, *tmp; - struct pci_dev *pdev = dev->port; - - pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap); - slot = kzalloc(sizeof(*slot), GFP_KERNEL); - if (!slot) - return -ENOMEM; - slot->number = (slot_cap & PCI_EXP_SLTCAP_PSN) >> 19; - list_for_each_entry(tmp, &dummy_slots, list) { - if (tmp->number == slot->number) - dup_slot_id++; - } - list_add_tail(&slot->list, &dummy_slots); - handle = ACPI_HANDLE(&pdev->dev); - if (!acpi_slot_detected && acpi_pci_detect_ejectable(handle)) - acpi_slot_detected = 1; - return -ENODEV; /* dummy driver always returns error */ -} - -static struct pcie_port_service_driver __initdata dummy_driver = { - .name = "pciehp_dummy", - .port_type = PCIE_ANY_PORT, - .service = PCIE_PORT_SERVICE_HP, - .probe = dummy_probe, -}; - -static int __init select_detection_mode(void) -{ - struct dummy_slot *slot, *tmp; - - if (pcie_port_service_register(&dummy_driver)) - return PCIEHP_DETECT_ACPI; - pcie_port_service_unregister(&dummy_driver); - list_for_each_entry_safe(slot, tmp, &dummy_slots, list) { - list_del(&slot->list); - kfree(slot); - } - if (acpi_slot_detected && dup_slot_id) - return PCIEHP_DETECT_ACPI; - return PCIEHP_DETECT_PCIE; -} - -void __init pciehp_acpi_slot_detection_init(void) -{ - slot_detection_mode = parse_detect_mode(); - if (slot_detection_mode != PCIEHP_DETECT_AUTO) - goto out; - slot_detection_mode = select_detection_mode(); -out: - if (slot_detection_mode == PCIEHP_DETECT_ACPI) - info("Using ACPI for slot detection.\n"); -} Index: linux-pm/drivers/pci/hotplug/pciehp.h =================================================================== --- linux-pm.orig/drivers/pci/hotplug/pciehp.h +++ linux-pm/drivers/pci/hotplug/pciehp.h @@ -167,21 +167,4 @@ static inline const char *slot_name(stru return hotplug_slot_name(slot->hotplug_slot); } -#ifdef CONFIG_ACPI -#include <linux/pci-acpi.h> - -void __init pciehp_acpi_slot_detection_init(void); -int pciehp_acpi_slot_detection_check(struct pci_dev *dev); - -static inline void pciehp_firmware_init(void) -{ - pciehp_acpi_slot_detection_init(); -} -#else -#define pciehp_firmware_init() do {} while (0) -static inline int pciehp_acpi_slot_detection_check(struct pci_dev *dev) -{ - return 0; -} -#endif /* CONFIG_ACPI */ #endif /* _PCIEHP_H */ -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
