ath5k: fix SIFS time handling

ath5k uses 8 usec as a sifs time, extracted from the initvals, whereas the standard requires a sifs time of 10. The difference originates from the fact that the SIFS register has an offset of 2 usec. Fix the SIFS time definition to use the standard value of 10 usec and subtract 2 usecs when writing the SIFS register. Signed-off-by: Felix Fietkau <nbd@openwrt.org> Signed-off-by: John W. Linville <linville@tuxdriver.com>
git-mirror · Apr 12, 2011 · 488a501 · 488a501
1 parent a27049e
commit 488a501
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Showing 2 changed files with 2 additions and 3 deletions.
diff --git a/drivers/net/wireless/ath/ath5k/ath5k.h b/drivers/net/wireless/ath/ath5k/ath5k.h
@@ -224,8 +224,7 @@
 
 /* SIFS */
 #define	AR5K_INIT_SIFS_TURBO			6
-/* XXX: 8 from initvals 10 from standard */
-#define	AR5K_INIT_SIFS_DEFAULT_BG		8
+#define	AR5K_INIT_SIFS_DEFAULT_BG		10
 #define	AR5K_INIT_SIFS_DEFAULT_A		16
 #define	AR5K_INIT_SIFS_HALF_RATE		32
 #define AR5K_INIT_SIFS_QUARTER_RATE		64

diff --git a/drivers/net/wireless/ath/ath5k/qcu.c b/drivers/net/wireless/ath/ath5k/qcu.c
@@ -519,7 +519,7 @@ int ath5k_hw_set_ifs_intervals(struct ath5k_hw *ah, unsigned int slot_time)
 		return -EINVAL;
 
 	sifs = ath5k_hw_get_default_sifs(ah);
-	sifs_clock = ath5k_hw_htoclock(ah, sifs);
+	sifs_clock = ath5k_hw_htoclock(ah, sifs - 2);
 
 	/* EIFS
 	 * Txtime of ack at lowest rate + SIFS + DIFS