port->lock is unlocked in each branch in altera_jtaguart_console_putc(), so do it before the "if". "status" needs not be under the lock, as the register was already read. Cc: Tobias Klauser <tklauser@xxxxxxxxxx> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> --- drivers/tty/serial/altera_jtaguart.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/tty/serial/altera_jtaguart.c b/drivers/tty/serial/altera_jtaguart.c index ac8ce418de36..c2d154d78e54 100644 --- a/drivers/tty/serial/altera_jtaguart.c +++ b/drivers/tty/serial/altera_jtaguart.c @@ -310,11 +310,12 @@ static void altera_jtaguart_console_putc(struct uart_port *port, unsigned char c spin_lock_irqsave(&port->lock, flags); while (!altera_jtaguart_tx_space(port, &status)) { + spin_unlock_irqrestore(&port->lock, flags); + if ((status & ALTERA_JTAGUART_CONTROL_AC_MSK) == 0) { - spin_unlock_irqrestore(&port->lock, flags); return; /* no connection activity */ } - spin_unlock_irqrestore(&port->lock, flags); + cpu_relax(); spin_lock_irqsave(&port->lock, flags); } -- 2.37.3