[PATCH 004/102] ath9k_hw: revert chainmask to user configuration after calibration

[Luis Henriques]

3.5.7.10 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Felix Fietkau <nbd at openwrt.org>

commit 74632d11a133b5baf6b9d622dd19d2f944d93d94 upstream.

The commit 'ath9k_hw: fix calibration issues on chainmask that don't
include chain 0' changed the hardware chainmask to the chip chainmask
for the duration of the calibration, but the revert to user
configuration in the reset path runs too early.

That causes some issues with limiting the number of antennas (including
spurious failure in hardware-generated packets).

Fix this by reverting the chainmask after the essential parts of the
calibration that need the workaround, and before NF calibration is run.

Signed-off-by: Felix Fietkau <nbd at openwrt.org>
Reported-by: Wojciech Dubowik <Wojciech.Dubowik at neratec.com>
Tested-by: Wojciech Dubowik <Wojciech.Dubowik at neratec.com>
Signed-off-by: John W. Linville <linville at tuxdriver.com>
[ luis: adjust context ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/net/wireless/ath/ath9k/ar9003_calib.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/wireless/ath/ath9k/ar9003_calib.c b/drivers/net/wireless/ath/ath9k/ar9003_calib.c
index 53aeca7..601213d 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_calib.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_calib.c
@@ -910,6 +910,7 @@ static bool ar9003_hw_init_cal(struct ath_hw *ah,
 					  AR_PHY_CL_TAB_1,
 					  AR_PHY_CL_TAB_2 };
 
+	/* Use chip chainmask only for calibration */
 	ar9003_hw_set_chain_masks(ah, ah->caps.rx_chainmask, ah->caps.tx_chainmask);
 
 	if (rtt) {
@@ -1057,6 +1058,9 @@ skip_tx_iqcal:
 		ar9003_hw_rtt_disable(ah);
 	}
 
+	/* Revert chainmask to runtime parameters */
+	ar9003_hw_set_chain_masks(ah, ah->rxchainmask, ah->txchainmask);
+
 	/* Initialize list pointers */
 	ah->cal_list = ah->cal_list_last = ah->cal_list_curr = NULL;
 	ah->supp_cals = IQ_MISMATCH_CAL;
-- 
1.8.1.2