pch_uart: Fix rx error interrupt setting issue

commit 9539dfb7 upstream.

Rx Error interrupt(E.G. parity error) is not enabled.
So, when parity error occurs, error interrupt is not occurred.
As a result, the received data is not dropped.

This patch adds enable/disable rx error interrupt code.
Signed-off-by: Tomoya MORINAGA <tomoya.rohm@gmail.com>
Acked-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[Backported by Tomoya MORINGA: adjusted context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

drivers/tty/serial/pch_uart.c

@@ -660,7 +660,8 @@ static void pch_dma_rx_complete(void *arg)
 		tty_flip_buffer_push(tty);
 	tty_kref_put(tty);
 	async_tx_ack(priv->desc_rx);
-	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_RX_INT);
+	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_RX_INT |
+					    PCH_UART_HAL_RX_ERR_INT);
 }
 
 static void pch_dma_tx_complete(void *arg)
@@ -715,7 +716,8 @@ static int handle_rx_to(struct eg20t_port *priv)
 	int rx_size;
 	int ret;
 	if (!priv->start_rx) {
-		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_RX_INT);
+		pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_RX_INT |
+						     PCH_UART_HAL_RX_ERR_INT);
 		return 0;
 	}
 	buf = &priv->rxbuf;
@@ -977,11 +979,13 @@ static irqreturn_t pch_uart_interrupt(int irq, void *dev_id)
 		case PCH_UART_IID_RDR:	/* Received Data Ready */
 			if (priv->use_dma) {
 				pch_uart_hal_disable_interrupt(priv,
-							PCH_UART_HAL_RX_INT);
+						PCH_UART_HAL_RX_INT |
+						PCH_UART_HAL_RX_ERR_INT);
 				ret = dma_handle_rx(priv);
 				if (!ret)
 					pch_uart_hal_enable_interrupt(priv,
-							PCH_UART_HAL_RX_INT);
+						PCH_UART_HAL_RX_INT |
+						PCH_UART_HAL_RX_ERR_INT);
 			} else {
 				ret = handle_rx(priv);
 			}
@@ -1107,7 +1111,8 @@ static void pch_uart_stop_rx(struct uart_port *port)
 	struct eg20t_port *priv;
 	priv = container_of(port, struct eg20t_port, port);
 	priv->start_rx = 0;
-	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_RX_INT);
+	pch_uart_hal_disable_interrupt(priv, PCH_UART_HAL_RX_INT |
+					     PCH_UART_HAL_RX_ERR_INT);
 	priv->int_dis_flag = 1;
 }
 
@@ -1201,7 +1206,8 @@ static int pch_uart_startup(struct uart_port *port)
 		pch_request_dma(port);
 
 	priv->start_rx = 1;
-	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_RX_INT);
+	pch_uart_hal_enable_interrupt(priv, PCH_UART_HAL_RX_INT |
+					    PCH_UART_HAL_RX_ERR_INT);
 	uart_update_timeout(port, CS8, default_baud);
 
 	return 0;