[PATCH ath-next v3] wifi: ath12k: Fix incorrect rates sent to firmware

[Roopni Devanathan]

From: Pradeep Kumar Chitrapu <quic_pradeepc at quicinc.com>

Before firmware assert, if there is a station interface in the device
which is not associated with an AP, the basic rates are set to zero.
Following this, during firmware recovery, when basic rates are zero,
ath12k driver is sending invalid rate codes, which are negative values,
to firmware. This results in firmware assert.

Fix this by checking if rate codes are valid, before sending them
to the firmware.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1

Signed-off-by: Pradeep Kumar Chitrapu <quic_pradeepc at quicinc.com>
Signed-off-by: Roopni Devanathan <quic_rdevanat at quicinc.com>
---
v3:
 - Modified the use of API ffs().
v2:
 - Replaced API ffs() to API __ffs().
---
 drivers/net/wireless/ath/ath12k/mac.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
index 9fda97667d4e..b7e4bb00e87c 100644
--- a/drivers/net/wireless/ath/ath12k/mac.c
+++ b/drivers/net/wireless/ath/ath12k/mac.c
@@ -3450,7 +3450,10 @@ static void ath12k_recalculate_mgmt_rate(struct ath12k *ar,
 	}
 
 	sband = hw->wiphy->bands[def->chan->band];
-	basic_rate_idx = ffs(bss_conf->basic_rates) - 1;
+	if (bss_conf->basic_rates)
+		basic_rate_idx = __ffs(bss_conf->basic_rates);
+	else
+		basic_rate_idx = 0;
 	bitrate = sband->bitrates[basic_rate_idx].bitrate;
 
 	hw_rate_code = ath12k_mac_get_rate_hw_value(bitrate);
@@ -3983,10 +3986,14 @@ static void ath12k_mac_bss_info_changed(struct ath12k *ar,
 		band = def.chan->band;
 		mcast_rate = info->mcast_rate[band];
 
-		if (mcast_rate > 0)
+		if (mcast_rate > 0) {
 			rateidx = mcast_rate - 1;
-		else
-			rateidx = ffs(info->basic_rates) - 1;
+		} else {
+			if (info->basic_rates)
+				rateidx = __ffs(info->basic_rates);
+			else
+				rateidx = 0;
+		}
 
 		if (ar->pdev->cap.supported_bands & WMI_HOST_WLAN_5G_CAP)
 			rateidx += ATH12K_MAC_FIRST_OFDM_RATE_IDX;

base-commit: b6f473c96421b8b451a8df8ccb620bcd71d4b3f4
-- 
2.34.1