[3/3] ath9k_hw: fix a noise floor calibration related race condition

Commit Message

Felix Fietkau July 28, 2010, 5:45 p.m. UTC

None

Patch

diff --git a/drivers/net/wireless/ath/ath9k/ar9002_calib.c b/drivers/net/wireless/ath/ath9k/ar9002_calib.c
index 4a7bcfa..916cde7 100644
--- a/drivers/net/wireless/ath/ath9k/ar9002_calib.c
+++ b/drivers/net/wireless/ath/ath9k/ar9002_calib.c
@@ -687,8 +687,13 @@  static bool ar9002_hw_calibrate(struct ath_hw *ah,
 {
 	bool iscaldone = true;
 	struct ath9k_cal_list *currCal = ah->cal_list_curr;
+	bool nfcal, nfcal_pending = false;
 
-	if (currCal &&
+	nfcal = !!(REG_READ(ah, AR_PHY_AGC_CONTROL) & AR_PHY_AGC_CONTROL_NF);
+	if (ah->caldata)
+		nfcal_pending = ah->caldata->nfcal_pending;
+
+	if (currCal && !nfcal &&
 	    (currCal->calState == CAL_RUNNING ||
 	     currCal->calState == CAL_WAITING)) {
 		iscaldone = ar9002_hw_per_calibration(ah, chan,
@@ -704,7 +709,7 @@  static bool ar9002_hw_calibrate(struct ath_hw *ah,
 	}
 
 	/* Do NF cal only at longer intervals */
-	if (longcal) {
+	if (longcal || nfcal_pending) {
 		/* Do periodic PAOffset Cal */
 		ar9002_hw_pa_cal(ah, false);
 		ar9002_hw_olc_temp_compensation(ah);
@@ -713,16 +718,18 @@  static bool ar9002_hw_calibrate(struct ath_hw *ah,
 		 * Get the value from the previous NF cal and update
 		 * history buffer.
 		 */
-		ath9k_hw_getnf(ah, chan);
-
-		/*
-		 * Load the NF from history buffer of the current channel.
-		 * NF is slow time-variant, so it is OK to use a historical
-		 * value.
-		 */
-		ath9k_hw_loadnf(ah, ah->curchan);
+		if (ath9k_hw_getnf(ah, chan)) {
+			/*
+			 * Load the NF from history buffer of the current
+			 * channel.
+			 * NF is slow time-variant, so it is OK to use a
+			 * historical value.
+			 */
+			ath9k_hw_loadnf(ah, ah->curchan);
+		}
 
-		ath9k_hw_start_nfcal(ah);
+		if (longcal)
+			ath9k_hw_start_nfcal(ah);
 	}
 
 	return iscaldone;
@@ -873,6 +880,9 @@  static bool ar9002_hw_init_cal(struct ath_hw *ah, struct ath9k_channel *chan)
 	REG_WRITE(ah, AR_PHY_AGC_CONTROL,
 		  REG_READ(ah, AR_PHY_AGC_CONTROL) | AR_PHY_AGC_CONTROL_NF);
 
+	if (ah->caldata)
+		ah->caldata->nfcal_pending = true;
+
 	ah->cal_list = ah->cal_list_last = ah->cal_list_curr = NULL;
 
 	/* Enable IQ, ADC Gain and ADC DC offset CALs */
diff --git a/drivers/net/wireless/ath/ath9k/calib.c b/drivers/net/wireless/ath/ath9k/calib.c
index 52460bc..787657b 100644
--- a/drivers/net/wireless/ath/ath9k/calib.c
+++ b/drivers/net/wireless/ath/ath9k/calib.c
@@ -156,6 +156,9 @@  EXPORT_SYMBOL(ath9k_hw_reset_calvalid);
 
 void ath9k_hw_start_nfcal(struct ath_hw *ah)
 {
+	if (ah->caldata)
+		ah->caldata->nfcal_pending = true;
+
 	REG_SET_BIT(ah, AR_PHY_AGC_CONTROL,
 		    AR_PHY_AGC_CONTROL_ENABLE_NF);
 	REG_SET_BIT(ah, AR_PHY_AGC_CONTROL,
@@ -282,8 +285,7 @@  static void ath9k_hw_nf_sanitize(struct ath_hw *ah, s16 *nf)
 	}
 }
 
-int16_t ath9k_hw_getnf(struct ath_hw *ah,
-		       struct ath9k_channel *chan)
+bool ath9k_hw_getnf(struct ath_hw *ah, struct ath9k_channel *chan)
 {
 	struct ath_common *common = ath9k_hw_common(ah);
 	int16_t nf, nfThresh;
@@ -293,7 +295,7 @@  int16_t ath9k_hw_getnf(struct ath_hw *ah,
 	struct ath9k_hw_cal_data *caldata = ah->caldata;
 
 	if (!caldata)
-		return ath9k_hw_get_default_nf(ah, chan);
+		return false;
 
 	chan->channelFlags &= (~CHANNEL_CW_INT);
 	if (REG_READ(ah, AR_PHY_AGC_CONTROL) & AR_PHY_AGC_CONTROL_NF) {
@@ -301,7 +303,7 @@  int16_t ath9k_hw_getnf(struct ath_hw *ah,
 			  "NF did not complete in calibration window\n");
 		nf = 0;
 		caldata->rawNoiseFloor = nf;
-		return caldata->rawNoiseFloor;
+		return false;
 	} else {
 		ath9k_hw_do_getnf(ah, nfarray);
 		ath9k_hw_nf_sanitize(ah, nfarray);
@@ -317,11 +319,10 @@  int16_t ath9k_hw_getnf(struct ath_hw *ah,
 	}
 
 	h = caldata->nfCalHist;
-
+	caldata->nfcal_pending = false;
 	ath9k_hw_update_nfcal_hist_buffer(h, nfarray);
 	caldata->rawNoiseFloor = h[0].privNF;
-
-	return ah->caldata->rawNoiseFloor;
+	return true;
 }
 
 void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah,
diff --git a/drivers/net/wireless/ath/ath9k/calib.h b/drivers/net/wireless/ath/ath9k/calib.h
index 09a0ed2..8381e81 100644
--- a/drivers/net/wireless/ath/ath9k/calib.h
+++ b/drivers/net/wireless/ath/ath9k/calib.h
@@ -110,8 +110,7 @@  struct ath9k_pacal_info{
 bool ath9k_hw_reset_calvalid(struct ath_hw *ah);
 void ath9k_hw_start_nfcal(struct ath_hw *ah);
 void ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan);
-int16_t ath9k_hw_getnf(struct ath_hw *ah,
-		       struct ath9k_channel *chan);
+bool ath9k_hw_getnf(struct ath_hw *ah, struct ath9k_channel *chan);
 void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah,
 				  struct ath9k_channel *chan);
 s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan);
diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index c1b7011..399f7c1 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -354,6 +354,7 @@  struct ath9k_hw_cal_data {
 	int8_t qCoff;
 	int16_t rawNoiseFloor;
 	bool paprd_done;
+	bool nfcal_pending;
 	u16 small_signal_gain[AR9300_MAX_CHAINS];
 	u32 pa_table[AR9300_MAX_CHAINS][PAPRD_TABLE_SZ];
 	struct ath9k_nfcal_hist nfCalHist[NUM_NF_READINGS];