[PATCH v4 4/4] net: ethernet: ti: cpts: fix fifo read in cpts_find_ts

From: Grygorii Strashko
Date: Fri Jul 28 2017 - 18:31:38 EST


Now the call chain
cpts_find_ts()
|- cpts_fifo_read(cpts, CPTS_EV_PUSH)

will stop reading CPTS FIFO if PUSH event is found. But this is not
expected and CPTS FIFI should be completely drained here. This is most
probably copy-paste error and it has no negative impact as CPTS_EV_PUSH
should not be present in FIFO without TS_PUSH request and
cpts_systim_read() and cpts_find_ts() synchronized by spin_lock.

Correct above by calling cpts_fifo_read() with -1 parameter, so it will
read all CPTS event from FIFO.

Signed-off-by: Grygorii Strashko <grygorii.strashko@xxxxxx>
---
drivers/net/ethernet/ti/cpts.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/ti/cpts.c b/drivers/net/ethernet/ti/cpts.c
index 95a0076..c2121d2 100644
--- a/drivers/net/ethernet/ti/cpts.c
+++ b/drivers/net/ethernet/ti/cpts.c
@@ -364,7 +364,7 @@ static u64 cpts_find_ts(struct cpts *cpts, struct sk_buff *skb, int ev_type)
return 0;

spin_lock_irqsave(&cpts->lock, flags);
- cpts_fifo_read(cpts, CPTS_EV_PUSH);
+ cpts_fifo_read(cpts, -1);
list_for_each_safe(this, next, &cpts->events) {
event = list_entry(this, struct cpts_event, list);
if (event_expired(event)) {
--
2.10.1