ath5k: Fix reset sequence for AR5212 in general and RF5111 in particular

Take care to handle register 0xa228 exactly as in the HAL released by
Atheros. This change is required to make ath5k work again on my system
since commit 2203d6be (ath5k: Misc hw_reset updates), thus fixing a
regression in 2.6.27 and therefore hopefully eligible for inclusion into
a stable release.

v2: Only overwrite initial register values on later revisions of AR5212
    chips.
v3: Use standard macros to manipulate the register.
Signed-off-by: Elias Oltmanns <eo@nebensachen.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath5k/initvals.c

@@ -806,6 +806,8 @@ static const struct ath5k_ini_mode ar5212_rf5111_ini_mode_end[] = {
 		{ 0x00000000, 0x00000000, 0x00000000, 0x00000000, 0x00000000 } },
 	{ AR5K_PHY(642),
 		{ 0xd03e6788, 0xd03e6788, 0xd03e6788, 0xd03e6788, 0xd03e6788 } },
+	{ 0xa228,
+		{ 0x000001b5, 0x000001b5, 0x000001b5, 0x000001b5, 0x000001b5 } },
 	{ 0xa23c,
 		{ 0x13c889af, 0x13c889af, 0x13c889af, 0x13c889af, 0x13c889af } },
 };

drivers/net/wireless/ath5k/reset.c

@@ -537,9 +537,10 @@ int ath5k_hw_reset(struct ath5k_hw *ah, enum nl80211_iftype op_mode,
 		mdelay(1);
 
 		/*
-		 * Write some more initial register settings
+		 * Write some more initial register settings for revised chips
 		 */
-		if (ah->ah_version == AR5K_AR5212) {
+		if (ah->ah_version == AR5K_AR5212 &&
+		    ah->ah_phy_revision > 0x41) {
 			ath5k_hw_reg_write(ah, 0x0002a002, 0x982c);
 
 			if (channel->hw_value == CHANNEL_G)
@@ -558,19 +559,10 @@ int ath5k_hw_reset(struct ath5k_hw *ah, enum nl80211_iftype op_mode,
 			else
 				ath5k_hw_reg_write(ah, 0x00000000, 0x994c);
 
-			/* Some bits are disabled here, we know nothing about
-			 * register 0xa228 yet, most of the times this ends up
-			 * with a value 0x9b5 -haven't seen any dump with
-			 * a different value- */
-			/* Got this from decompiling binary HAL */
-			data = ath5k_hw_reg_read(ah, 0xa228);
-			data &= 0xfffffdff;
-			ath5k_hw_reg_write(ah, data, 0xa228);
-
-			data = ath5k_hw_reg_read(ah, 0xa228);
-			data &= 0xfffe03ff;
-			ath5k_hw_reg_write(ah, data, 0xa228);
-			data = 0;
+			/* Got this from legacy-hal */
+			AR5K_REG_DISABLE_BITS(ah, 0xa228, 0x200);
+
+			AR5K_REG_MASKED_BITS(ah, 0xa228, 0x800, 0xfffe03ff);
 
 			/* Just write 0x9b5 ? */
 			/* ath5k_hw_reg_write(ah, 0x000009b5, 0xa228); */