From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
If a PCI bridge (or PCIe port) that is runtime-suspended gets an
ACPI hotplug notification, such as a bus check, it has to be resumed
before re-scanning the devices below it, or those devices will not
be accessible and will be treated as hot-removed.
Make that happen and let the bridge suspend again after the bus
below it has been re-scanned.
This is a replacement for commit 16468c783cb4 (ACPI / hotplug / PCI:
Runtime resume bridge before rescan) that has been reverted,
because it introduced a system resume regression (due to missing
bridge->pci_dev checks that are necessary in case the notification
is targeted at the host bridge) and it is necessary for the code
added by commit 006d44e49a25 (PCI: Add runtime PM support for PCIe
ports) to work as expected.
Tested-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/pci/hotplug/acpiphp_glue.c | 6 ++++++
1 file changed, 6 insertions(+)
Index: linux-pm/drivers/pci/hotplug/acpiphp_glue.c
===================================================================
--- linux-pm.orig/drivers/pci/hotplug/acpiphp_glue.c
+++ linux-pm/drivers/pci/hotplug/acpiphp_glue.c
@@ -675,6 +675,9 @@ static void acpiphp_check_bridge(struct
if (bridge->is_going_away)
return;
+ if (bridge->pci_dev)
+ pm_runtime_get_sync(&bridge->pci_dev->dev);
+
list_for_each_entry(slot, &bridge->slots, node) {
struct pci_bus *bus = slot->bus;
struct pci_dev *dev, *tmp;
@@ -694,6 +697,9 @@ static void acpiphp_check_bridge(struct
disable_slot(slot);
}
}
+
+ if (bridge->pci_dev)
+ pm_runtime_put(&bridge->pci_dev->dev);
}
/*
--
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
