igc: Fix launchtime before start of cycle

It is possible (verified on a running system) that frames are processed
by igc_tx_launchtime with a txtime before the start of the cycle
(baset_est).

However, the result of txtime - baset_est is written into a u32,
leading to a wrap around to a positive number. The following
launchtime > 0 check will only branch to executing launchtime = 0
if launchtime is already 0.

Fix it by using a s32 before checking launchtime > 0.

Fixes: db0b124f02ba ("igc: Enhance Qbv scheduling by using first flag bit")
Signed-off-by: Florian Kauer <[email protected]>
Reviewed-by: Kurt Kanzenbach <[email protected]>
Tested-by: Naama Meir <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>

0 files changed, 0 insertions, 0 deletions