1 files changed, 41 insertions, 2 deletions

diff --git a/drivers/net/usb/cdc_mbim.c b/drivers/net/usb/cdc_mbim.c
index 80d27719ba38..bc23273d0455 100644
--- a/drivers/net/usb/cdc_mbim.c
+++ b/drivers/net/usb/cdc_mbim.c
@@ -107,15 +107,54 @@ static const struct net_device_ops cdc_mbim_netdev_ops = {
         .ndo_vlan_rx_kill_vid = cdc_mbim_rx_kill_vid,
 };
 
+/* Change the control interface altsetting and update the .driver_info
+ * pointer if the matching entry after changing class codes points to
+ * a different struct
+ */
+static int cdc_mbim_set_ctrlalt(struct usbnet *dev, struct usb_interface *intf, u8 alt)
+{
+        struct usb_driver *driver = to_usb_driver(intf->dev.driver);
+        const struct usb_device_id *id;
+        struct driver_info *info;
+        int ret;
+
+        ret = usb_set_interface(dev->udev,
+                                intf->cur_altsetting->desc.bInterfaceNumber,
+                                alt);
+        if (ret)
+                return ret;
+
+        id = usb_match_id(intf, driver->id_table);
+        if (!id)
+                return -ENODEV;
+
+        info = (struct driver_info *)id->driver_info;
+        if (info != dev->driver_info) {
+                dev_dbg(&intf->dev, "driver_info updated to '%s'\n",
+                        info->description);
+                dev->driver_info = info;
+        }
+        return 0;
+}
+
 static int cdc_mbim_bind(struct usbnet *dev, struct usb_interface *intf)
 {
         struct cdc_ncm_ctx *ctx;
         struct usb_driver *subdriver = ERR_PTR(-ENODEV);
         int ret = -ENODEV;
-        u8 data_altsetting = cdc_ncm_select_altsetting(dev, intf);
+        u8 data_altsetting = 1;
         struct cdc_mbim_state *info = (void *)&dev->data;
 
-        /* Probably NCM, defer for cdc_ncm_bind */
+        /* should we change control altsetting on a NCM/MBIM function? */
+        if (cdc_ncm_select_altsetting(intf) == CDC_NCM_COMM_ALTSETTING_MBIM) {
+                data_altsetting = CDC_NCM_DATA_ALTSETTING_MBIM;
+                ret = cdc_mbim_set_ctrlalt(dev, intf, CDC_NCM_COMM_ALTSETTING_MBIM);
+                if (ret)
+                        goto err;
+                ret = -ENODEV;
+        }
+
+        /* we will hit this for NCM/MBIM functions if prefer_mbim is false */
         if (!cdc_ncm_comm_intf_is_mbim(intf->cur_altsetting))
                 goto err;