From 265e6cab59db6261e1c2e4e144680252e5aceca8 Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Thu, 12 Apr 2012 00:27:03 +0800 Subject: [PATCH 2/3] PCI: correctly detect ACPI PCI host bridge objects The code in pci_root_hp.c depends on function acpi_is_root_bridge() to check whether an ACPI object is a PCI host bridge or not. If an ACPI device hasn't been created for the ACPI object yet, function acpi_is_root_bridge() will return false even if the object is a PCI host bridge object. That behavior will cause two issues: 1) No ACPI notification handler installed for PCI host bridges absent at startup, so hotplug events for those bridges won't be handled. 2) rescan_root_bridge() can't reenumerate offlined PCI host bridges because the ACPI devices have been already destroyed. So use acpi_match_object_info_ids() to correctly detect PCI host bridges. -v2: update to use acpi_match_object_info_ids() from Tang Chen - Yinghai Signed-off-by: Jiang Liu Signed-off-by: Yinghai Lu Cc: Len Brown Cc: linux-acpi@vger.kernel.org --- drivers/acpi/pci_root_hp.c | 25 ++++++++++++++++++++++++- 1 files changed, 24 insertions(+), 1 deletions(-) diff --git a/drivers/acpi/pci_root_hp.c b/drivers/acpi/pci_root_hp.c index 2aebf78..3edec7f 100644 --- a/drivers/acpi/pci_root_hp.c +++ b/drivers/acpi/pci_root_hp.c @@ -19,6 +19,12 @@ struct acpi_root_bridge { u32 flags; }; +static const struct acpi_device_id root_device_ids[] = { + {"PNP0A03", 0}, + {"PNP0A08", 0}, + {"", 0}, +}; + /* bridge flags */ #define ROOT_BRIDGE_HAS_EJ0 (0x00000002) #define ROOT_BRIDGE_HAS_PS3 (0x00000080) @@ -256,6 +262,23 @@ static void handle_hotplug_event_root(acpi_handle handle, u32 type, _handle_hotplug_event_root); } +static bool acpi_is_root_bridge_object(acpi_handle handle) +{ + struct acpi_device_info *info = NULL; + acpi_status status; + bool ret; + + status = acpi_get_object_info(handle, &info); + if (ACPI_FAILURE(status)) + return false; + + ret = !acpi_match_object_info_ids(info, root_device_ids); + + kfree(info); + + return ret; +} + static acpi_status __init find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv) { @@ -264,7 +287,7 @@ find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv) .pointer = objname }; int *count = (int *)context; - if (!acpi_is_root_bridge(handle)) + if (!acpi_is_root_bridge_object(handle)) return AE_OK; (*count)++; -- 1.7.7