ath9k: make PA linearization optional, disabled by default and fix checks

Some checks for PA linearization support checked ATH9K_HW_CAP_PAPRD and some
used the EEPROM ops, leading to issues in tx power handling, since those
two can be out of sync.

Disable the feature by default, since it has been reported that it can
cause damage to the rx path under some circumstances. It can now be enabled
for testing via debugfs.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

5 files changed, 8 insertions, 7 deletions

diff --git a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
index 2588848f4a8..d066f2516e4 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
@@ -2982,6 +2982,10 @@ static u32 ath9k_hw_ar9300_get_eeprom(struct ath_hw *ah,
 	case EEP_RX_MASK:
 		return pBase->txrxMask & 0xf;
 	case EEP_PAPRD:
+		if (AR_SREV_9462(ah))
+			return false;
+		if (!ah->config.enable_paprd);
+			return false;
 		return !!(pBase->featureEnable & BIT(5));
 	case EEP_CHAIN_MASK_REDUCE:
 		return (pBase->miscConfiguration >> 0x3) & 0x1;
diff --git a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c
index 68b643c8943..c8ef30127ad 100644
--- a/drivers/net/wireless/ath/ath9k/debug.c
+++ b/drivers/net/wireless/ath/ath9k/debug.c
@@ -1577,6 +1577,8 @@ int ath9k_init_debug(struct ath_hw *ah)
 			    sc->debug.debugfs_phy, sc, &fops_tx_chainmask);
 	debugfs_create_file("disable_ani", S_IRUSR | S_IWUSR,
 			    sc->debug.debugfs_phy, sc, &fops_disable_ani);
+	debugfs_create_bool("paprd", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
+			    &sc->sc_ah->config.enable_paprd);
 	debugfs_create_file("regidx", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
 			    sc, &fops_regidx);
 	debugfs_create_file("regval", S_IRUSR | S_IWUSR, sc->debug.debugfs_phy,
diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c
index 48af40151d2..4faf0a39587 100644
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -2497,10 +2497,6 @@ int ath9k_hw_fill_cap_info(struct ath_hw *ah)
 		pCap->rx_status_len = sizeof(struct ar9003_rxs);
 		pCap->tx_desc_len = sizeof(struct ar9003_txc);
 		pCap->txs_len = sizeof(struct ar9003_txs);
-		if (!ah->config.paprd_disable &&
-		    ah->eep_ops->get_eeprom(ah, EEP_PAPRD) &&
-		    !AR_SREV_9462(ah))
-			pCap->hw_caps |= ATH9K_HW_CAP_PAPRD;
 	} else {
 		pCap->tx_desc_len = sizeof(struct ath_desc);
 		if (AR_SREV_9280_20(ah))
diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index 6599a75f01f..de6968fc64f 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -236,7 +236,6 @@ enum ath9k_hw_caps {
 	ATH9K_HW_CAP_LDPC			= BIT(6),
 	ATH9K_HW_CAP_FASTCLOCK			= BIT(7),
 	ATH9K_HW_CAP_SGI_20			= BIT(8),
-	ATH9K_HW_CAP_PAPRD			= BIT(9),
 	ATH9K_HW_CAP_ANT_DIV_COMB		= BIT(10),
 	ATH9K_HW_CAP_2GHZ			= BIT(11),
 	ATH9K_HW_CAP_5GHZ			= BIT(12),
@@ -287,12 +286,12 @@ struct ath9k_ops_config {
 	u8 pcie_clock_req;
 	u32 pcie_waen;
 	u8 analog_shiftreg;
-	u8 paprd_disable;
 	u32 ofdm_trig_low;
 	u32 ofdm_trig_high;
 	u32 cck_trig_high;
 	u32 cck_trig_low;
 	u32 enable_ani;
+	u32 enable_paprd;
 	int serialize_regmode;
 	bool rx_intr_mitigation;
 	bool tx_intr_mitigation;
diff --git a/drivers/net/wireless/ath/ath9k/link.c b/drivers/net/wireless/ath/ath9k/link.c
index 825a29cc931..7b88b9c39cc 100644
--- a/drivers/net/wireless/ath/ath9k/link.c
+++ b/drivers/net/wireless/ath/ath9k/link.c
@@ -423,7 +423,7 @@ set_timer:
 		cal_interval = min(cal_interval, (u32)short_cal_interval);
 
 	mod_timer(&common->ani.timer, jiffies + msecs_to_jiffies(cal_interval));
-	if ((sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_PAPRD) && ah->caldata) {
+	if (ah->eep_ops->get_eeprom(ah, EEP_PAPRD) && ah->caldata) {
 		if (!ah->caldata->paprd_done)
 			ieee80211_queue_work(sc->hw, &sc->paprd_work);
 		else if (!ah->paprd_table_write_done)