diff options
Diffstat (limited to 'drivers/usb/core/hub.c')
| -rw-r--r-- | drivers/usb/core/hub.c | 33 |
1 files changed, 15 insertions, 18 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index aeb50bb6ba9..3e9c4d477d1 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -4655,9 +4655,13 @@ static void hub_port_connect(struct usb_hub *hub, int port1, u16 portstatus, if (!(portstatus & USB_PORT_STAT_CONNECTION) || test_bit(port1, hub->removed_bits)) { - /* maybe switch power back on (e.g. root hub was reset) */ + /* + * maybe switch power back on (e.g. root hub was reset) + * but only if the port isn't owned by someone else. + */ if (hub_is_port_power_switchable(hub) - && !port_is_power_on(hub, portstatus)) + && !port_is_power_on(hub, portstatus) + && !port_dev->port_owner) set_port_feature(hdev, port1, USB_PORT_FEAT_POWER); if (portstatus & USB_PORT_STAT_ENABLE) @@ -5589,26 +5593,19 @@ EXPORT_SYMBOL_GPL(usb_reset_device); * possible; depending on how the driver attached to each interface * handles ->pre_reset(), the second reset might happen or not. * - * - If a driver is unbound and it had a pending reset, the reset will - * be cancelled. - * - * - This function can be called during .probe() or .disconnect() - * times. On return from .disconnect(), any pending resets will be - * cancelled. - * - * There is no no need to lock/unlock the @reset_ws as schedule_work() - * does its own. + * - If the reset is delayed so long that the interface is unbound from + * its driver, the reset will be skipped. * - * NOTE: We don't do any reference count tracking because it is not - * needed. The lifecycle of the work_struct is tied to the - * usb_interface. Before destroying the interface we cancel the - * work_struct, so the fact that work_struct is queued and or - * running means the interface (and thus, the device) exist and - * are referenced. + * - This function can be called during .probe(). It can also be called + * during .disconnect(), but doing so is pointless because the reset + * will not occur. If you really want to reset the device during + * .disconnect(), call usb_reset_device() directly -- but watch out + * for nested unbinding issues! */ void usb_queue_reset_device(struct usb_interface *iface) { - schedule_work(&iface->reset_ws); + if (schedule_work(&iface->reset_ws)) + usb_get_intf(iface); } EXPORT_SYMBOL_GPL(usb_queue_reset_device); |