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>

1 files changed, 3 insertions, 10 deletions

diff --git a/net/caif/caif_usb.c b/net/caif/caif_usb.c
index 582f80c8ef3d..3ebc8cbc91ff 100644
--- 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);