ath5k: Fix functions for getting/setting slot time

Functions ath5k_hw_get_slot_time and ath5k_hw_set_slot_time were
converting microseconds to clocks only for AR5210, although it's needed
for all supported devices. The conversion was moved outside the
hardware-specific branches.

The original code also limited minimum slot time to 9, while turbo modes
use 6, this was fixed too.
Signed-off-by: NLukas Turek <8an@praha12.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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

@@ -520,12 +520,16 @@ int ath5k_hw_reset_tx_queue(struct ath5k_hw *ah, unsigned int queue)
  */
 unsigned int ath5k_hw_get_slot_time(struct ath5k_hw *ah)
 {
+	unsigned int slot_time_clock;
+
 	ATH5K_TRACE(ah->ah_sc);
+
 	if (ah->ah_version == AR5K_AR5210)
-		return ath5k_hw_clocktoh(ath5k_hw_reg_read(ah,
-				AR5K_SLOT_TIME) & 0xffff, ah->ah_turbo);
+		slot_time_clock = ath5k_hw_reg_read(ah, AR5K_SLOT_TIME);
 	else
-		return ath5k_hw_reg_read(ah, AR5K_DCU_GBL_IFS_SLOT) & 0xffff;
+		slot_time_clock = ath5k_hw_reg_read(ah, AR5K_DCU_GBL_IFS_SLOT);
+
+	return ath5k_hw_clocktoh(slot_time_clock & 0xffff, ah->ah_turbo);
 }
 
 /*
@@ -533,15 +537,17 @@ unsigned int ath5k_hw_get_slot_time(struct ath5k_hw *ah)
  */
 int ath5k_hw_set_slot_time(struct ath5k_hw *ah, unsigned int slot_time)
 {
+	u32 slot_time_clock = ath5k_hw_htoclock(slot_time, ah->ah_turbo);
+
 	ATH5K_TRACE(ah->ah_sc);
-	if (slot_time < AR5K_SLOT_TIME_9 || slot_time > AR5K_SLOT_TIME_MAX)
+
+	if (slot_time < 6 || slot_time_clock > AR5K_SLOT_TIME_MAX)
 		return -EINVAL;
 
 	if (ah->ah_version == AR5K_AR5210)
-		ath5k_hw_reg_write(ah, ath5k_hw_htoclock(slot_time,
-				ah->ah_turbo), AR5K_SLOT_TIME);
+		ath5k_hw_reg_write(ah, slot_time_clock, AR5K_SLOT_TIME);
 	else
-		ath5k_hw_reg_write(ah, slot_time, AR5K_DCU_GBL_IFS_SLOT);
+		ath5k_hw_reg_write(ah, slot_time_clock, AR5K_DCU_GBL_IFS_SLOT);
 
 	return 0;
 }