From: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx> commit 04b5bfe3dc94e64d0590c54045815cb5183fb095 upstream. In atmel_shutdown() we call atmel_stop_rx() and atmel_stop_tx() functions. Prevent the rx restart that is implemented in RS485 or ISO7816 modes when calling atmel_stop_tx() by using the atomic information tasklet_shutdown that is already in place for this purpose. Fixes: 98f2082c3ac4 ("tty/serial: atmel: enforce tasklet init and termination sequences") Signed-off-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20200210152053.8289-1-nicolas.ferre@xxxxxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/tty/serial/atmel_serial.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -490,7 +490,8 @@ static void atmel_stop_tx(struct uart_po atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask); if (atmel_uart_is_half_duplex(port)) - atmel_start_rx(port); + if (!atomic_read(&atmel_port->tasklet_shutdown)) + atmel_start_rx(port); }