serial: uartps: Fix interrupt mask issue to handle the RX interrupts properly

This patch Correct the RX interrupt mask value to handle the
RX interrupts properly.

Fixes: c8dbdc84 ("serial: xuartps: Rewrite the interrupt handling logic")
Signed-off-by: Nava kishore Manne <nava.manne@xilinx.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/xilinx_uartps.c

@@ -123,7 +123,7 @@ MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255");
 #define CDNS_UART_IXR_RXTRIG	0x00000001 /* RX FIFO trigger interrupt */
 #define CDNS_UART_IXR_RXFULL	0x00000004 /* RX FIFO full interrupt. */
 #define CDNS_UART_IXR_RXEMPTY	0x00000002 /* RX FIFO empty interrupt. */
-#define CDNS_UART_IXR_MASK	0x00001FFF /* Valid bit mask */
+#define CDNS_UART_IXR_RXMASK	0x000021e7 /* Valid RX bit mask */
 
 	/*
 	 * Do not enable parity error interrupt for the following
@@ -364,7 +364,7 @@ static irqreturn_t cdns_uart_isr(int irq, void *dev_id)
 		cdns_uart_handle_tx(dev_id);
 		isrstatus &= ~CDNS_UART_IXR_TXEMPTY;
 	}
-	if (isrstatus & CDNS_UART_IXR_MASK)
+	if (isrstatus & CDNS_UART_IXR_RXMASK)
 		cdns_uart_handle_rx(dev_id, isrstatus);
 
 	spin_unlock(&port->lock);