ethtool: Call ethtool's get/set_settings callbacks with cleaned data

This makes sure that when a driver calls the ethtool's
get/set_settings() callback of another driver, the data passed to it
is clean. This guarantees that speed_hi will be zeroed correctly if
the called callback doesn't explicitely set it: we are sure we don't
get a corrupted speed from the underlying driver. We also take care of
setting the cmd field appropriately (ETHTOOL_GSET/SSET).

This applies to dev_ethtool_get_settings(), which now makes sure it
sets up that ethtool command parameter correctly before passing it to
drivers. This also means that whoever calls dev_ethtool_get_settings()
does not have to clean the ethtool command parameter. This function
also becomes an exported symbol instead of an inline.

All drivers visible to make allyesconfig under x86_64 have been
updated.

Signed-off-by: David Decotigny <decot@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/usb/dm9601.c b/drivers/net/usb/dm9601.c
index 5002f5b..1d93133 100644
--- a/drivers/net/usb/dm9601.c
+++ b/drivers/net/usb/dm9601.c
@@ -599,13 +599,13 @@
 
 static int dm9601_link_reset(struct usbnet *dev)
 {
-	struct ethtool_cmd ecmd;
+	struct ethtool_cmd ecmd = { .cmd = ETHTOOL_GSET };
 
 	mii_check_media(&dev->mii, 1, 1);
 	mii_ethtool_gset(&dev->mii, &ecmd);
 
-	netdev_dbg(dev->net, "link_reset() speed: %d duplex: %d\n",
-		   ecmd.speed, ecmd.duplex);
+	netdev_dbg(dev->net, "link_reset() speed: %u duplex: %d\n",
+		   ethtool_cmd_speed(&ecmd), ecmd.duplex);
 
 	return 0;
 }