[SERIAL] Move interrupt-time spinlocking inside serial8250_handle_port()

All call sites for serial8250_handle_port() acquired the port spinlock
and released it afterwards.  This is a needless duplication of code.
Move the spinlocking inside serial8250_handle_port().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 8 insertions, 7 deletions

diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index ad20d2dd85d7..56dcfd93bdc4 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -1281,7 +1281,11 @@ static unsigned int check_modem_status(struct uart_8250_port *up)
 static inline void
 serial8250_handle_port(struct uart_8250_port *up, struct pt_regs *regs)
 {
-        unsigned int status = serial_inp(up, UART_LSR);
+        unsigned int status;
+
+        spin_lock(&up->port.lock);
+
+        status = serial_inp(up, UART_LSR);
 
         DEBUG_INTR("status = %x...", status);
 
@@ -1290,6 +1294,8 @@ serial8250_handle_port(struct uart_8250_port *up, struct pt_regs *regs)
         check_modem_status(up);
         if (status & UART_LSR_THRE)
                 transmit_chars(up);
+
+        spin_unlock(&up->port.lock);
 }
 
 /*
@@ -1325,9 +1331,7 @@ static irqreturn_t serial8250_interrupt(int irq, void *dev_id, struct pt_regs *r
 
                 iir = serial_in(up, UART_IIR);
                 if (!(iir & UART_IIR_NO_INT)) {
-                        spin_lock(&up->port.lock);
                         serial8250_handle_port(up, regs);
-                        spin_unlock(&up->port.lock);
 
                         handled = 1;
 
@@ -1426,11 +1430,8 @@ static void serial8250_timeout(unsigned long data)
         unsigned int iir;
 
         iir = serial_in(up, UART_IIR);
-        if (!(iir & UART_IIR_NO_INT)) {
-                spin_lock(&up->port.lock);
+        if (!(iir & UART_IIR_NO_INT))
                 serial8250_handle_port(up, NULL);
-                spin_unlock(&up->port.lock);
-        }
 
         timeout = up->port.timeout;
         timeout = timeout > 6 ? (timeout / 2 - 2) : 1;