diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/usb/core/hub.c | 46 |
1 files changed, 44 insertions, 2 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index 8eb4da332f5..94789be54ca 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -644,6 +644,48 @@ static void hub_stop(struct usb_hub *hub) #ifdef CONFIG_PM +/* Try to identify which devices need USB-PERSIST handling */ +static int persistent_device(struct usb_device *udev) +{ + int i; + int retval; + struct usb_host_config *actconfig; + + /* Explicitly not marked persistent? */ + if (!udev->persist_enabled) + return 0; + + /* No active config? */ + actconfig = udev->actconfig; + if (!actconfig) + return 0; + + /* FIXME! We should check whether it's open here or not! */ + + /* + * Check that all the interface drivers have a + * 'reset_resume' entrypoint + */ + retval = 0; + for (i = 0; i < actconfig->desc.bNumInterfaces; i++) { + struct usb_interface *intf; + struct usb_driver *driver; + + intf = actconfig->interface[i]; + if (!intf->dev.driver) + continue; + driver = to_usb_driver(intf->dev.driver); + if (!driver->reset_resume) + return 0; + /* + * We have at least one driver, and that one + * has a reset_resume method. + */ + retval = 1; + } + return retval; +} + static void hub_restart(struct usb_hub *hub, int type) { struct usb_device *hdev = hub->hdev; @@ -689,8 +731,8 @@ static void hub_restart(struct usb_hub *hub, int type) * turn off the various status changes to prevent * khubd from disconnecting it later. */ - if (udev->persist_enabled && status == 0 && - !(portstatus & USB_PORT_STAT_ENABLE)) { + if (status == 0 && !(portstatus & USB_PORT_STAT_ENABLE) && + persistent_device(udev)) { if (portchange & USB_PORT_STAT_C_ENABLE) clear_port_feature(hub->hdev, port1, USB_PORT_FEAT_C_ENABLE); |