serial: uartps: Move the spinlock after the read of the tx empty
commit 107475685abfdee504bb0ef4824f15797f6d2d4d upstream.
Currently we are doing a read of the status register.
Move the spinlock after that as the reads need not be spinlock
protected. This patch prevents relaxing the cpu with spinlock held.
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Cc: Pavel Machek <pavel@denx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c
index 7cbee19..31950a3 100644
--- a/drivers/tty/serial/xilinx_uartps.c
+++ b/drivers/tty/serial/xilinx_uartps.c
@@ -686,8 +686,6 @@
unsigned int ctrl_reg, mode_reg, val;
int err;
- spin_lock_irqsave(&port->lock, flags);
-
/* Wait for the transmit FIFO to empty before making changes */
if (!(readl(port->membase + CDNS_UART_CR) &
CDNS_UART_CR_TX_DIS)) {
@@ -699,6 +697,7 @@
return;
}
}
+ spin_lock_irqsave(&port->lock, flags);
/* Disable the TX and RX to set baud rate */
ctrl_reg = readl(port->membase + CDNS_UART_CR);
