From: Tom Rix <trix@redhat.com>
Date: Sun, 13 Mar 2022 08:02:10 -0700
Subject: igb: zero hwtstamp by default
Patch-mainline: v5.18-rc1
Git-commit: 5d705de0cd3400b2721185430e0dddeff79d7871
References: jsc#PED-370

Clang static analysis reports this representative issue
igb_ptp.c:997:3: warning: The left operand of '+' is a
  garbage value
  ktime_add_ns(shhwtstamps.hwtstamp, adjust);
  ^            ~~~~~~~~~~~~~~~~~~~~

shhwtstamps.hwtstamp is set by a call to
igb_ptp_systim_to_hwtstamp().  In the switch-statement
for the hw type, the hwtstamp is zeroed for matches
but not the default case.  Move the memset out of
switch-statement.  This degarbages the default case
and reduces the size.

Some whitespace cleanup of empty lines

Signed-off-by: Tom Rix <trix@redhat.com>
Tested-by: Gurucharan G <gurucharanx.g@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/intel/igb/igb_ptp.c |    6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/intel/igb/igb_ptp.c
+++ b/drivers/net/ethernet/intel/igb/igb_ptp.c
@@ -165,23 +165,21 @@ static void igb_ptp_systim_to_hwtstamp(s
 	unsigned long flags;
 	u64 ns;
 
+	memset(hwtstamps, 0, sizeof(*hwtstamps));
+
 	switch (adapter->hw.mac.type) {
 	case e1000_82576:
 	case e1000_82580:
 	case e1000_i354:
 	case e1000_i350:
 		spin_lock_irqsave(&adapter->tmreg_lock, flags);
-
 		ns = timecounter_cyc2time(&adapter->tc, systim);
-
 		spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
 
-		memset(hwtstamps, 0, sizeof(*hwtstamps));
 		hwtstamps->hwtstamp = ns_to_ktime(ns);
 		break;
 	case e1000_i210:
 	case e1000_i211:
-		memset(hwtstamps, 0, sizeof(*hwtstamps));
 		/* Upper 32 bits contain s, lower 32 bits contain ns. */
 		hwtstamps->hwtstamp = ktime_set(systim >> 32,
 						systim & 0xFFFFFFFF);