diff options
Diffstat (limited to 'drivers/pci/pci-driver.c')
| -rw-r--r-- | drivers/pci/pci-driver.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c index 6b54b23b990b..099f46cd8e87 100644 --- a/drivers/pci/pci-driver.c +++ b/drivers/pci/pci-driver.c @@ -421,6 +421,12 @@ static void pci_device_shutdown(struct device *dev) pci_msix_shutdown(pci_dev); /* + * Turn off Bus Master bit on the device to tell it to not + * continue to do DMA + */ + pci_disable_device(pci_dev); + + /* * Devices may be enabled to wake up by runtime PM, but they need not * be supposed to wake up the system from its "power off" state (e.g. * ACPI S5). Therefore disable wakeup for all devices that aren't @@ -742,6 +748,18 @@ static int pci_pm_suspend_noirq(struct device *dev) pci_pm_set_unknown_state(pci_dev); + /* + * Some BIOSes from ASUS have a bug: If a USB EHCI host controller's + * PCI COMMAND register isn't 0, the BIOS assumes that the controller + * hasn't been quiesced and tries to turn it off. If the controller + * is already in D3, this can hang or cause memory corruption. + * + * Since the value of the COMMAND register doesn't matter once the + * device has been suspended, we can safely set it to 0 here. + */ + if (pci_dev->class == PCI_CLASS_SERIAL_USB_EHCI) + pci_write_config_word(pci_dev, PCI_COMMAND, 0); + return 0; } |