diff options
| -rw-r--r-- | drivers/usb/core/hub.c | 23 |
1 files changed, 16 insertions, 7 deletions
diff --git a/drivers/usb/core/hub.c b/drivers/usb/core/hub.c index f17d9ebc44af..81eb3e6b6592 100644 --- a/drivers/usb/core/hub.c +++ b/drivers/usb/core/hub.c @@ -3393,10 +3393,10 @@ static int usb_reset_and_verify_device(struct usb_device *udev) udev->descriptor = descriptor; /* for disconnect() calls */ goto re_enumerate; } - + + /* Restore the device's previous configuration */ if (!udev->actconfig) goto done; - ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0), USB_REQ_SET_CONFIGURATION, 0, udev->actconfig->desc.bConfigurationValue, 0, @@ -3409,16 +3409,25 @@ static int usb_reset_and_verify_device(struct usb_device *udev) } usb_set_device_state(udev, USB_STATE_CONFIGURED); + /* Put interfaces back into the same altsettings as before. + * Don't bother to send the Set-Interface request for interfaces + * that were already in altsetting 0; besides being unnecessary, + * many devices can't handle it. Instead just reset the host-side + * endpoint state. + */ for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) { struct usb_interface *intf = udev->actconfig->interface[i]; struct usb_interface_descriptor *desc; - /* set_interface resets host side toggle even - * for altsetting zero. the interface may have no driver. - */ desc = &intf->cur_altsetting->desc; - ret = usb_set_interface(udev, desc->bInterfaceNumber, - desc->bAlternateSetting); + if (desc->bAlternateSetting == 0) { + usb_disable_interface(udev, intf, true); + usb_enable_interface(udev, intf, true); + ret = 0; + } else { + ret = usb_set_interface(udev, desc->bInterfaceNumber, + desc->bAlternateSetting); + } if (ret < 0) { dev_err(&udev->dev, "failed to restore interface %d " "altsetting %d (error=%d)\n", |