tree 47e4a6de7df1c5d41bff61f8bfc81eb464b8d2c6
parent 873392ca514f87eae39f53b6944caf85b1a047cb
author Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com> 1229483258 +0900
committer Jesse Barnes <jbarnes@virtuousgeek.org> 1231355590 -0800

PCI: pciehp: add ACPI based slot detection

There is a problem that some non hot-pluggable PCIe slots are detected
as hot-pluggable by pciehp on some platforms. The immediate cause of
this problem is that hot-plug capable bit in the Slot Capabilities
register is set even for non hot-pluggable slots on those platforms.
It seems a BIOS/hardware problem, but we need workaround about that.

Some of those platforms define hot-pluggable PCIe slots on ACPI
namespace properly, while hot-plug capable bit in the Slot
Capabilities register is set improperly. So using ACPI namespace
information in pciehp to detect PCIe hot-pluggable slots would be a
workaround.

This patch adds 'pciehp_detect_mode' module option. When 'acpi' is
specified, pciehp uses ACPI namespace information to detect PCIe
hot-pluggable slots.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>