caif_usb: Make the driver name check more efficient

Use the device model to get just the name, rather than using the
ethtool API to get all driver information.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/caif/caif_usb.c b/net/caif/caif_usb.c
index 582f80c..3ebc8cb 100644 (file)
--- a/net/caif/caif_usb.c
+++ b/net/caif/caif_usb.c
@@ -128,17 +128,10 @@ static int cfusbl_device_notify(struct notifier_block *me, unsigned long what,
        struct cflayer *layer, *link_support;
        struct usbnet *usbnet;
        struct usb_device *usbdev;
-       struct ethtool_drvinfo drvinfo;
 
-       /*
-        * Quirks: High-jack ethtool to find if we have a NCM device,
-        * and find it's VID/PID.
-        */
-       if (dev->ethtool_ops == NULL || dev->ethtool_ops->get_drvinfo == NULL)
-               return 0;
-
-       dev->ethtool_ops->get_drvinfo(dev, &drvinfo);
-       if (strncmp(drvinfo.driver, "cdc_ncm", 7) != 0)
+       /* Check whether we have a NCM device, and find its VID/PID. */
+       if (!(dev->dev.parent && dev->dev.parent->driver &&
+             strcmp(dev->dev.parent->driver->name, "cdc_ncm") == 0))
                return 0;
 
        usbnet = netdev_priv(dev);