net: qmi_wwan: make dynamic device IDs work

The usbnet API use the device ID table to store a pointer to
a minidriver. Setting a generic pointer for dynamic device
IDs will in most cases make them work as expected.  usbnet
will otherwise treat the dynamic IDs as blacklisted. That is
rarely useful.

There is no standard class describing devices supported by
this driver, and most vendors don't even provide enough
information to allow vendor specific wildcard matching. The
result is that most of the supported devices must be
explicitly listed in the device table.  Allowing dynamic IDs
to work both simplifies testing and verification of new
devices, and provides a way for end users to use a device
before the ID is added to the driver.

Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 18 insertions, 1 deletions

diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c
index 85c983d52527..07743c14a6bc 100644
--- a/drivers/net/usb/qmi_wwan.c
+++ b/drivers/net/usb/qmi_wwan.c
@@ -600,10 +600,27 @@ static const struct usb_device_id products[] = {
 };
 MODULE_DEVICE_TABLE(usb, products);
 
+static int qmi_wwan_probe(struct usb_interface *intf, const struct usb_device_id *prod)
+{
+        struct usb_device_id *id = (struct usb_device_id *)prod;
+
+        /* Workaround to enable dynamic IDs.  This disables usbnet
+         * blacklisting functionality.  Which, if required, can be
+         * reimplemented here by using a magic "blacklist" value
+         * instead of 0 in the static device id table
+         */
+        if (!id->driver_info) {
+                dev_dbg(&intf->dev, "setting defaults for dynamic device id\n");
+                id->driver_info = (unsigned long)&qmi_wwan_shared;
+        }
+
+        return usbnet_probe(intf, id);
+}
+
 static struct usb_driver qmi_wwan_driver = {
         .name                 = "qmi_wwan",
         .id_table             = products,
-        .probe                = usbnet_probe,
+        .probe                = qmi_wwan_probe,
         .disconnect           = usbnet_disconnect,
         .suspend              = qmi_wwan_suspend,
         .resume               = qmi_wwan_resume,