cdc-ether: clean packet filter upon probe

There are devices that don't do reset all the way. So the packet filter should
be set to a sane initial value. Failure to do so leads to intermittent failures
of DHCP on some systems under some conditions.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 16 insertions, 0 deletions

diff --git a/drivers/net/usb/cdc_ether.c b/drivers/net/usb/cdc_ether.c
index 9ea4bfe5d318..2a32d9167d3b 100644
--- a/drivers/net/usb/cdc_ether.c
+++ b/drivers/net/usb/cdc_ether.c
@@ -341,6 +341,22 @@ next_desc:
                 usb_driver_release_interface(driver, info->data);
                 return -ENODEV;
         }
+
+        /* Some devices don't initialise properly. In particular
+         * the packet filter is not reset. There are devices that
+         * don't do reset all the way. So the packet filter should
+         * be set to a sane initial value.
+         */
+        usb_control_msg(dev->udev,
+                        usb_sndctrlpipe(dev->udev, 0),
+                        USB_CDC_SET_ETHERNET_PACKET_FILTER,
+                        USB_TYPE_CLASS | USB_RECIP_INTERFACE,
+                        USB_CDC_PACKET_TYPE_ALL_MULTICAST | USB_CDC_PACKET_TYPE_DIRECTED | USB_CDC_PACKET_TYPE_BROADCAST,
+                        intf->cur_altsetting->desc.bInterfaceNumber,
+                        NULL,
+                        0,
+                        USB_CTRL_SET_TIMEOUT
+                );
         return 0;
 
 bad_desc: