diff options
| -rw-r--r-- | drivers/tty/serial/8250/8250_port.c | 41 |
1 files changed, 26 insertions, 15 deletions
diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c index 0f16398cc86f..85b75ff0699e 100644 --- a/drivers/tty/serial/8250/8250_port.c +++ b/drivers/tty/serial/8250/8250_port.c @@ -2792,6 +2792,30 @@ static void serial8250_set_efr(struct uart_port *port, struct ktermios *termios) serial_port_out(port, efr_reg, efr); } +static void serial8250_set_fcr(struct uart_port *port, struct ktermios *termios) +{ + struct uart_8250_port *up = up_to_u8250p(port); + bool is_16750 = port->type == PORT_16750; + + if (is_16750) + serial_port_out(port, UART_FCR, up->fcr); + + /* + * LCR DLAB must be reset to enable 64-byte FIFO mode. If the FCR is written without DLAB + * set, this mode will be disabled. + */ + serial_port_out(port, UART_LCR, up->lcr); + + if (is_16750) + return; + + /* emulated UARTs (Lucent Venus 167x) need two steps */ + if (up->fcr & UART_FCR_ENABLE_FIFO) + serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO); + + serial_port_out(port, UART_FCR, up->fcr); +} + void serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, const struct ktermios *old) @@ -2823,22 +2847,9 @@ serial8250_do_set_termios(struct uart_port *port, struct ktermios *termios, serial8250_set_ier(port, termios); serial8250_set_efr(port, termios); serial8250_set_divisor(port, baud, quot, frac); - - /* - * LCR DLAB must be set to enable 64-byte FIFO mode. If the FCR - * is written without DLAB set, this mode will be disabled. - */ - if (port->type == PORT_16750) - serial_port_out(port, UART_FCR, up->fcr); - - serial_port_out(port, UART_LCR, up->lcr); /* reset DLAB */ - if (port->type != PORT_16750) { - /* emulated UARTs (Lucent Venus 167x) need two steps */ - if (up->fcr & UART_FCR_ENABLE_FIFO) - serial_port_out(port, UART_FCR, UART_FCR_ENABLE_FIFO); - serial_port_out(port, UART_FCR, up->fcr); /* set fcr */ - } + serial8250_set_fcr(port, termios); serial8250_set_mctrl(port, port->mctrl); + uart_port_unlock_irqrestore(port, flags); serial8250_rpm_put(up); |