From: Colin Ian King colin.king@canonical.com
commit 3ddb4ce1e6e3bd112778ab93bbd9092f23a878ec upstream.
Currently the expression lsr | UART_LSR_TEMT is always true and this seems suspect. I believe the intent was to mask lsr with UART_LSR_TEMT to check that bit, so the expression should be using the & operator instead. Fix this.
Fixes: b9c2470fb150 ("serial: tegra: flush the RX fifo on frame error") Signed-off-by: Colin Ian King colin.king@canonical.com Cc: stable stable@vger.kernel.org Link: https://lore.kernel.org/r/20210426105514.23268-1-colin.king@canonical.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/tty/serial/serial-tegra.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/tty/serial/serial-tegra.c +++ b/drivers/tty/serial/serial-tegra.c @@ -338,7 +338,7 @@ static void tegra_uart_fifo_reset(struct
do { lsr = tegra_uart_read(tup, UART_LSR); - if ((lsr | UART_LSR_TEMT) && !(lsr & UART_LSR_DR)) + if ((lsr & UART_LSR_TEMT) && !(lsr & UART_LSR_DR)) break; udelay(1); } while (--tmout);