[PATCH 5.15 270/846] iwlwifi: mvm: fix 32-bit build in FTM

[Greg Kroah-Hartman]

From: Johannes Berg <johannes.berg@xxxxxxxxx>

[ Upstream commit 8b0f92549f2c2458200935c12a2e2a6e80234cf5 ]

On a 32-bit build, the division here needs to be done
using do_div(), otherwise the compiler will try to call
a function that doesn't exist, thus failing to build.

Fixes: b68bd2e3143a ("iwlwifi: mvm: Add FTM initiator RTT smoothing logic")
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
Link: https://lore.kernel.org/r/iwlwifi.20211219111352.e56cbf614a4d.Ib98004ccd2c7a55fd883a8ea7eebd810f406dec6@changeid
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c b/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c
index 03e5bf5cb9094..c7fee6a2f7fd4 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c
@@ -1054,7 +1054,8 @@ static void iwl_mvm_ftm_rtt_smoothing(struct iwl_mvm *mvm,
 	overshoot = IWL_MVM_FTM_INITIATOR_SMOOTH_OVERSHOOT;
 	alpha = IWL_MVM_FTM_INITIATOR_SMOOTH_ALPHA;
 
-	rtt_avg = (alpha * rtt + (100 - alpha) * resp->rtt_avg) / 100;
+	rtt_avg = alpha * rtt + (100 - alpha) * resp->rtt_avg;
+	do_div(rtt_avg, 100);
 
 	IWL_DEBUG_INFO(mvm,
 		       "%pM: prev rtt_avg=%lld, new rtt_avg=%lld, rtt=%lld\n",
-- 
2.34.1