ath5k: clarify srev comparison for CCMP check

As Pavel Roskin noted, the check for mac version as copied from
legacy_hal made no sense.  This replaces it with the equivalent
and makes up a suitable #define for the mac version legacy_hal
checked.
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath5k/ath5k.h

@@ -306,6 +306,7 @@ struct ath5k_srev_name {
 #define AR5K_SREV_AR5311B	0x30 /* Spirit */
 #define AR5K_SREV_AR5211	0x40 /* Oahu */
 #define AR5K_SREV_AR5212	0x50 /* Venice */
+#define AR5K_SREV_AR5212_V4	0x54 /* ??? */
 #define AR5K_SREV_AR5213	0x55 /* ??? */
 #define AR5K_SREV_AR5213A	0x59 /* Hainan */
 #define AR5K_SREV_AR2413	0x78 /* Griffin lite */

drivers/net/wireless/ath/ath5k/attach.c

@@ -318,12 +318,9 @@ struct ath5k_hw *ath5k_hw_attach(struct ath5k_softc *sc, u8 mac_version)
 
 	/* Crypto settings */
 	ee = &ah->ah_capabilities.cap_eeprom;
-	ah->ah_aes_support =
+	ah->ah_aes_support = srev >= AR5K_SREV_AR5212_V4 &&
 		(ee->ee_version >= AR5K_EEPROM_VERSION_5_0 &&
-		 !AR5K_EEPROM_AES_DIS(ee->ee_misc5) &&
-		 (ah->ah_mac_version > (AR5K_SREV_AR5212 >> 4) ||
-		  (ah->ah_mac_version == (AR5K_SREV_AR5212 >> 4) &&
-		   ah->ah_mac_revision >= (AR5K_SREV_AR5211 >> 4))));
+		 !AR5K_EEPROM_AES_DIS(ee->ee_misc5));
 
 	if (srev >= AR5K_SREV_AR2414) {
 		ah->ah_combined_mic = true;