tty: serial: 8250_core.c Bug fix for Exar chips.

commit b790f210fe8423eff881b2a8a93ba5dbc45534d0 upstream.

The sleep function was updated to put the serial port to sleep only when necessary.
This appears to resolve the errant behavior of the driver as described in
Kernel Bug 61961 – "My Exar Corp. XR17C/D152 Dual PCI UART modem does not
work with 3.8.0".

Signed-off-by: Michael Welling <mwelling@ieee.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/serial/8250/8250_core.c b/drivers/tty/serial/8250/8250_core.c
index d28d7afc128a2811079b33f30e7ebbe97adbbd76..b167665b7de2a816c79f7b7a33360f1cf83fc5a9 100644 (file)
--- a/drivers/tty/serial/8250/8250_core.c
+++ b/drivers/tty/serial/8250/8250_core.c
@@ -555,7 +555,7 @@ static void serial8250_set_sleep(struct uart_8250_port *p, int sleep)
         */
        if ((p->port.type == PORT_XR17V35X) ||
           (p->port.type == PORT_XR17D15X)) {
-               serial_out(p, UART_EXAR_SLEEP, 0xff);
+               serial_out(p, UART_EXAR_SLEEP, sleep ? 0xff : 0);
                return;
        }