serial: 8250: Add helper for clearing IER

A number of places want to clear IER with the same CAP_UUE trick.
Create a helper for that.

Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://lore.kernel.org/r/20220816120759.11552-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
index 39b35a61958c04e43e1862b84f9ff7829324cbf5..25e4761e3c57dcfa255331b28dc718c6a0fe4b73 100644 (file)
--- a/drivers/tty/serial/8250/8250_port.c
+++ b/drivers/tty/serial/8250/8250_port.c
@@ -752,6 +752,14 @@ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
        serial8250_rpm_put(p);
 }
 
+static void serial8250_clear_IER(struct uart_8250_port *up)
+{
+       if (up->capabilities & UART_CAP_UUE)
+               serial_out(up, UART_IER, UART_IER_UUE);
+       else
+               serial_out(up, UART_IER, 0);
+}
+
 #ifdef CONFIG_SERIAL_8250_RSA
 /*
  * Attempts to turn on the RSA FIFO.  Returns zero on failure.
@@ -1329,10 +1337,7 @@ static void autoconfig(struct uart_8250_port *up)
        serial8250_out_MCR(up, save_mcr);
        serial8250_clear_fifos(up);
        serial_in(up, UART_RX);
-       if (up->capabilities & UART_CAP_UUE)
-               serial_out(up, UART_IER, UART_IER_UUE);
-       else
-               serial_out(up, UART_IER, 0);
+       serial8250_clear_IER(up);
 
 out_unlock:
        spin_unlock_irqrestore(&port->lock, flags);
@@ -2142,10 +2147,7 @@ static void serial8250_put_poll_char(struct uart_port *port,
         *      First save the IER then disable the interrupts
         */
        ier = serial_port_in(port, UART_IER);
-       if (up->capabilities & UART_CAP_UUE)
-               serial_port_out(port, UART_IER, UART_IER_UUE);
-       else
-               serial_port_out(port, UART_IER, 0);
+       serial8250_clear_IER(up);
 
        wait_for_xmitr(up, UART_LSR_BOTH_EMPTY);
        /*
@@ -3383,11 +3385,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
         *      First save the IER then disable the interrupts
         */
        ier = serial_port_in(port, UART_IER);
-
-       if (up->capabilities & UART_CAP_UUE)
-               serial_port_out(port, UART_IER, UART_IER_UUE);
-       else
-               serial_port_out(port, UART_IER, 0);
+       serial8250_clear_IER(up);
 
        /* check scratch reg to see if port powered off during system sleep */
        if (up->canary && (up->canary != serial_port_in(port, UART_SCR))) {