ath9k: add a missing null pointer check and some further cleanup

SVN-Revision: 22036

package/mac80211/patches/530-ath9k_nf_sanitize.patch

@@ -25,7 +25,27 @@
  }
 --- a/drivers/net/wireless/ath/ath9k/ar9002_phy.c
 +++ b/drivers/net/wireless/ath/ath9k/ar9002_phy.c
-@@ -520,6 +520,30 @@ static void ar9002_hw_do_getnf(struct at
+@@ -481,9 +481,6 @@ static void ar9002_hw_do_getnf(struct at
+ 	ath_print(common, ATH_DBG_CALIBRATE,
+ 		  "NF calibrated [ctl] [chain 0] is %d\n", nf);
+ 
+-	if (AR_SREV_9271(ah) && (nf >= -114))
+-		nf = -116;
+-
+ 	nfarray[0] = nf;
+ 
+ 	if (!AR_SREV_9285(ah) && !AR_SREV_9271(ah)) {
+@@ -503,9 +500,6 @@ static void ar9002_hw_do_getnf(struct at
+ 	ath_print(common, ATH_DBG_CALIBRATE,
+ 		  "NF calibrated [ext] [chain 0] is %d\n", nf);
+ 
+-	if (AR_SREV_9271(ah) && (nf >= -114))
+-		nf = -116;
+-
+ 	nfarray[3] = nf;
+ 
+ 	if (!AR_SREV_9285(ah) && !AR_SREV_9271(ah)) {
+@@ -520,6 +514,30 @@ static void ar9002_hw_do_getnf(struct at
  	}
  }
  
@@ -56,7 +76,7 @@
  void ar9002_hw_attach_phy_ops(struct ath_hw *ah)
  {
  	struct ath_hw_private_ops *priv_ops = ath9k_hw_private_ops(ah);
-@@ -532,4 +556,6 @@ void ar9002_hw_attach_phy_ops(struct ath
+@@ -532,4 +550,6 @@ void ar9002_hw_attach_phy_ops(struct ath
  	priv_ops->olc_init = ar9002_olc_init;
  	priv_ops->compute_pll_control = ar9002_hw_compute_pll_control;
  	priv_ops->do_getnf = ar9002_hw_do_getnf;
@@ -302,7 +322,7 @@
 -		noise_floor = AR_PHY_CCA_MAX_AR9285_GOOD_VALUE;
 -	else if (AR_SREV_9287(ah))
 -		noise_floor = AR_PHY_CCA_MAX_AR9287_GOOD_VALUE;
-+	if (IS_CHAN_2GHZ(ah->curchan))
++	if (!ah->curchan || IS_CHAN_2GHZ(ah->curchan))
 +		limit = &ah->nf_2g;
  	else
 -		noise_floor = AR_PHY_CCA_MAX_AR5416_GOOD_VALUE;