[PATCH v2] iwlwifi: mvm: Use div_s64 instead of do_div in iwl_mvm_debug_range_resp

Nathan Chancellor
2019-02-21T08:08:34Z

Clang warns:

drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c:465:2: warning:
comparison of distinct pointer types ('typeof ((rtt_avg)) *' (aka 'long
long *') and 'uint64_t *' (aka 'unsigned long long *'))
[-Wcompare-distinct-pointer-types]
do_div(rtt_avg, 6666);
^~~~~~~~~~~~~~~~~~~~~
include/asm-generic/div64.h:222:28: note: expanded from macro 'do_div'
(void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
~~~~~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~~
1 warning generated.

do_div expects an unsigned dividend. Use div_s64, which expects a signed
dividend.

Fixes: 937b10c0de68 ("iwlwifi: mvm: add debug prints for FTM")
Link: https://github.com/ClangBuiltLinux/linux/issues/372
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
---

v1 -> v2:

* Fix logic (as the return value of div{,64}_s64 must be used), thanks
to Arnd for the review.

drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c b/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c
index e9822a3ec373..94132cfd1f56 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/ftm-initiator.c
@@ -460,9 +460,7 @@ static int iwl_mvm_ftm_range_resp_valid(struct iwl_mvm *mvm, u8 request_id,
static void iwl_mvm_debug_range_resp(struct iwl_mvm *mvm, u8 index,
struct cfg80211_pmsr_result *res)
{
- s64 rtt_avg = res->ftm.rtt_avg * 100;
-
- do_div(rtt_avg, 6666);
+ s64 rtt_avg = div_s64(res->ftm.rtt_avg * 100, 6666);

IWL_DEBUG_INFO(mvm, "entry %d\n", index);
IWL_DEBUG_INFO(mvm, "\tstatus: %d\n", res->status);
--
2.21.0.rc1