ethtool: add speed/duplex validation functions

BugLink: http://bugs.launchpad.net/bugs/1581132

Add functions which check if the speed/duplex are defined.
Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
(cherry picked from commit 103a8ad1)
Signed-off-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Acked-by: Tim Gardner <tim.gardner@canonical.com>
Acked-by: Brad Figg <brad.figg@canonical.com>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>

include/uapi/linux/ethtool.h

@@ -1316,11 +1316,45 @@ enum ethtool_sfeatures_retval_bits {
 
 #define SPEED_UNKNOWN		-1
 
+static inline int ethtool_validate_speed(__u32 speed)
+{
+	switch (speed) {
+	case SPEED_10:
+	case SPEED_100:
+	case SPEED_1000:
+	case SPEED_2500:
+	case SPEED_5000:
+	case SPEED_10000:
+	case SPEED_20000:
+	case SPEED_25000:
+	case SPEED_40000:
+	case SPEED_50000:
+	case SPEED_56000:
+	case SPEED_100000:
+	case SPEED_UNKNOWN:
+		return 1;
+	}
+
+	return 0;
+}
+
 /* Duplex, half or full. */
 #define DUPLEX_HALF		0x00
 #define DUPLEX_FULL		0x01
 #define DUPLEX_UNKNOWN		0xff
 
+static inline int ethtool_validate_duplex(__u8 duplex)
+{
+	switch (duplex) {
+	case DUPLEX_HALF:
+	case DUPLEX_FULL:
+	case DUPLEX_UNKNOWN:
+		return 1;
+	}
+
+	return 0;
+}
+
 /* Which connector port. */
 #define PORT_TP			0x00
 #define PORT_AUI		0x01