ath9k_hw: calibrate PA input for PA predistortion

Re-train if the calibrated PA linearization curve is out of bounds
(affects AR933x and AR9485).

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/drivers/net/wireless/ath/ath9k/link.c b/drivers/net/wireless/ath/ath9k/link.c
index d4549e9..1c24192 100644
--- a/drivers/net/wireless/ath/ath9k/link.c
+++ b/drivers/net/wireless/ath/ath9k/link.c
@@ -254,6 +254,7 @@
 	int chain_ok = 0;
 	int chain;
 	int len = 1800;
+	int ret;
 
 	if (!caldata)
 		return;
@@ -302,7 +303,13 @@
 			break;
 		}
 
-		if (ar9003_paprd_create_curve(ah, caldata, chain)) {
+		ret = ar9003_paprd_create_curve(ah, caldata, chain);
+		if (ret == -EINPROGRESS) {
+			ath_dbg(common, CALIBRATE,
+				"PAPRD curve on chain %d needs to be re-trained\n",
+				chain);
+			break;
+		} else if (ret) {
 			ath_dbg(common, CALIBRATE,
 				"PAPRD create curve failed on chain %d\n",
 				chain);