[PATCH 5.15.y] usb: octeon-hcd: fix the FIFO-flush timeout computation

[Sasha Levin <sashal@kernel.org>]

From: Orgad Shaneh <orgads@gmail.com>

[ Upstream commit 4c7a1b9f1f1979f2b3b69428ada12680695159c2 ]

cvmx_wait_tx_rx() computes its 100us deadline from
(u64)octeon_get_clock_rate - the address of the function, not its
return value; the parentheses have been missing since the
CVMX_WAIT_FOR_FIELD32 macro became a function. The cast makes it
compile silently, and the resulting deadline is effectively infinite.

On a healthy controller the flush bit clears on the first read and
nothing is noticed. On a controller whose PHY did not come up (for
example when the reference-clock configuration is wrong for the board),
txfflsh/rxfflsh never clear and probe spins forever in __delay() -
observed as a hard hang with a soft-lockup splat on a CN5020 board,
where the board watchdog then resets the system with no console output.

Call the function, restoring the 100us timeout the code always
intended.

Fixes: 3e195a80e096 ("Staging: octeon-usb: Replaces CVMX_WAIT_FOR_FIELD32 macro with a function")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-5
Signed-off-by: Orgad Shaneh <orgads@gmail.com>
Link: https://patch.msgid.link/20260901193100.1352110-1-orgads@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/staging/octeon-usb/octeon-hcd.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/staging/octeon-usb/octeon-hcd.c b/drivers/staging/octeon-usb/octeon-hcd.c
index a1cd81d4a1144..16fb72eb3d185 100644
--- a/drivers/staging/octeon-usb/octeon-hcd.c
+++ b/drivers/staging/octeon-usb/octeon-hcd.c
@@ -578,7 +578,7 @@ static int cvmx_wait_tx_rx(struct octeon_hcd *usb, int fflsh_type)
 	int result;
 	u64 address = CVMX_USBCX_GRSTCTL(usb->index);
 	u64 done = cvmx_get_cycle() + 100 *
-		   (u64)octeon_get_clock_rate / 1000000;
+		   (u64)octeon_get_clock_rate() / 1000000;
 	union cvmx_usbcx_grstctl c;
 
 	while (1) {
-- 
2.53.0