PCI PM: Introduce device flag wakeup_prepared
Introduce a new PCI device flag, wakeup_prepared, to prevent PCI
wake-up preparation code from being executed twice in a row for the
same device and for the same purpose.
Reviewed-by: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 84a6d6d..dcdfb22 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -1225,6 +1225,10 @@
if (enable && !device_may_wakeup(&dev->dev))
return -EINVAL;
+ /* Don't do the same thing twice in a row for one device. */
+ if (!!enable == !!dev->wakeup_prepared)
+ return 0;
+
/*
* According to "PCI System Architecture" 4th ed. by Tom Shanley & Don
* Anderson we should be doing PME# wake enable followed by ACPI wake
@@ -1241,9 +1245,12 @@
error = platform_pci_sleep_wake(dev, true);
if (ret)
ret = error;
+ if (!ret)
+ dev->wakeup_prepared = true;
} else {
platform_pci_sleep_wake(dev, false);
pci_pme_active(dev, false);
+ dev->wakeup_prepared = false;
}
return ret;
@@ -1365,6 +1372,7 @@
int pm;
u16 pmc;
+ dev->wakeup_prepared = false;
dev->pm_cap = 0;
/* find PCI PM capability in list */
diff --git a/include/linux/pci.h b/include/linux/pci.h
index d80ed87..f5c7cd3 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -241,6 +241,7 @@
unsigned int d1_support:1; /* Low power state D1 is supported */
unsigned int d2_support:1; /* Low power state D2 is supported */
unsigned int no_d1d2:1; /* Only allow D0 and D3 */
+ unsigned int wakeup_prepared:1;
#ifdef CONFIG_PCIEASPM
struct pcie_link_state *link_state; /* ASPM link state. */