The attached patch fixes the problem of very weak packets being send out
after periodic calibration

Signed-off-by: Karol Kowalik <karol.kowalik@cnri.dit.ie>
Index: madwifi-dfs-r3252/ath/if_ath.c
===================================================================
--- madwifi-dfs-r3252.orig/ath/if_ath.c	2008-01-26 03:56:26.461576124 +0100
+++ madwifi-dfs-r3252/ath/if_ath.c	2008-01-26 03:58:50.628969172 +0100
@@ -8875,6 +8875,9 @@
 	struct ieee80211com *ic = &sc->sc_ic;
 	/* u_int32_t nchans; */
 	HAL_BOOL isIQdone = AH_FALSE;
+	u_int8_t papd_probe_power;
+	u_int8_t papd_probe_power_max = 63;
+	u_int16_t crnt_power_hdBm = sc->sc_curtxpow;
 
 	sc->sc_stats.ast_per_cal++;
 	DPRINTF(sc, ATH_DEBUG_CALIBRATE, 
@@ -8912,6 +8915,20 @@
 		sc->sc_stats.ast_per_calfail++;
 	}
 
+	/*
+	* After calibration is done we need to update AR5K_PHY_PAPD_PROBE
+	* register with the probe_tx_power equal to current tx_power
+	* otherwise a power drop may be observed
+	*/
+	crnt_power_hdBm = crnt_power_hdBm <= ic->ic_txpowlimit ? crnt_power_hdBm : ic->ic_txpowlimit;
+	papd_probe_power = papd_probe_power_max - (ic->ic_txpowlimit - crnt_power_hdBm);
+#define AR5K_PHY_PAPD_PROBE_TX_NEXT 0x00008000
+#define AR5K_PHY_PAPD_PROBE 0x9930
+	OS_REG_WRITE(ah, AR5K_PHY_PAPD_PROBE,
+	AR5K_PHY_PAPD_PROBE_TX_NEXT | (papd_probe_power << 9));
+#undef AR5K_PHY_PAPD_PROBE_TX_NEXT
+#undef AR5K_PHY_PAPD_PROBE
+
 	ath_hal_process_noisefloor(ah);
 	if (isIQdone == AH_TRUE) {
 		/* Unless user has overridden calibration interval,