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Diffstat (limited to 'drivers/usb/host/ehci-hub.c')
| -rw-r--r-- | drivers/usb/host/ehci-hub.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/drivers/usb/host/ehci-hub.c b/drivers/usb/host/ehci-hub.c index 9ab4a4d9768..b2f64506840 100644 --- a/drivers/usb/host/ehci-hub.c +++ b/drivers/usb/host/ehci-hub.c @@ -42,6 +42,12 @@ static int ehci_hub_control( u16 wLength ); +static int persist_enabled_on_companion(struct usb_device *udev, void *unused) +{ + return !udev->maxchild && udev->persist_enabled && + udev->bus->root_hub->speed < USB_SPEED_HIGH; +} + /* After a power loss, ports that were owned by the companion must be * reset so that the companion can still own them. */ @@ -56,6 +62,16 @@ static void ehci_handover_companion_ports(struct ehci_hcd *ehci) if (!ehci->owned_ports) return; + /* + * USB 1.1 devices are mostly HIDs, which don't need to persist across + * suspends. If we ensure that none of our companion's devices have + * persist_enabled (by looking through all USB 1.1 buses in the system), + * we can skip this and avoid slowing resume down. Devices without + * persist will just get reenumerated shortly after resume anyway. + */ + if (!usb_for_each_dev(NULL, persist_enabled_on_companion)) + return; + /* Make sure the ports are powered */ port = HCS_N_PORTS(ehci->hcs_params); while (port--) { |