serial: Test/disable MSIs if switching from N_PPS
Switching to the N_PPS line discipline may require enabling
modem status interrupts; conversely switching from N_PPS may
require disabling modem status interrupts.
Affected drivers:
8250
amba-pl010
atmel
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Russell King <linux@arm.linux.org.uk>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/amba-pl010.c b/drivers/tty/serial/amba-pl010.c
index 194108b..5d41d5b 100644
--- a/drivers/tty/serial/amba-pl010.c
+++ b/drivers/tty/serial/amba-pl010.c
@@ -106,6 +106,16 @@
writel(cr, uap->port.membase + UART010_CR);
}
+static void pl010_disable_ms(struct uart_port *port)
+{
+ struct uart_amba_port *uap = (struct uart_amba_port *)port;
+ unsigned int cr;
+
+ cr = readb(uap->port.membase + UART010_CR);
+ cr &= ~UART010_CR_MSIE;
+ writel(cr, uap->port.membase + UART010_CR);
+}
+
static void pl010_enable_ms(struct uart_port *port)
{
struct uart_amba_port *uap =
@@ -486,8 +496,14 @@
spin_lock_irq(&port->lock);
pl010_enable_ms(port);
spin_unlock_irq(&port->lock);
- } else
+ } else {
port->flags &= ~UPF_HARDPPS_CD;
+ if (!UART_ENABLE_MS(port, termios->c_cflag)) {
+ spin_lock_irq(&port->lock);
+ pl010_disable_ms(port);
+ spin_unlock_irq(&port->lock);
+ }
+ }
}
static const char *pl010_type(struct uart_port *port)