SERIAL: omap: fix set_mctrl() breakage
c538d20c7f (and maybe previous commits) broke set_mctrl() by making
it only capable of setting bits in the MCR register. This prevents
software controlled flow control and modem control line manipulation
via TIOCMSET/TIOCMBIC from working correctly.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 6ef4cc4..fb06def 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -504,7 +504,7 @@
static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
{
struct uart_omap_port *up = to_uart_omap_port(port);
- unsigned char mcr = 0;
+ unsigned char mcr = 0, old_mcr;
dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
if (mctrl & TIOCM_RTS)
@@ -519,8 +519,10 @@
mcr |= UART_MCR_LOOP;
pm_runtime_get_sync(up->dev);
- up->mcr = serial_in(up, UART_MCR);
- up->mcr |= mcr;
+ old_mcr = serial_in(up, UART_MCR);
+ old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
+ UART_MCR_DTR | UART_MCR_RTS);
+ up->mcr = old_mcr | mcr;
serial_out(up, UART_MCR, up->mcr);
pm_runtime_mark_last_busy(up->dev);
pm_runtime_put_autosuspend(up->dev);