tty: serial: fsl_lpuart: only enable Idle Line Interrupt for non-dma case

For the lpuart driver, the Idle Line Interrupt Enable now is only needed
for the CPU mode, so enable the UARTCTRL_ILIE at the correct place, and
clear it when shutdown.

Also need to configure the suitable UARTCTRL_IDLECFG, now the value is
0x7, represent 128 idle characters will trigger the Idle Line Interrupt.
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Link: https://lore.kernel.org/r/20221125101953.18753-2-sherry.sun@nxp.comSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/fsl_lpuart.c

@@ -5,6 +5,8 @@
  *  Copyright 2012-2014 Freescale Semiconductor, Inc.
  */
 
+#include <linux/bitfield.h>
+#include <linux/bits.h>
 #include <linux/clk.h>
 #include <linux/console.h>
 #include <linux/delay.h>
@@ -181,7 +183,7 @@
 #define UARTCTRL_SBK		0x00010000
 #define UARTCTRL_MA1IE		0x00008000
 #define UARTCTRL_MA2IE		0x00004000
-#define UARTCTRL_IDLECFG	0x00000100
+#define UARTCTRL_IDLECFG	GENMASK(10, 8)
 #define UARTCTRL_LOOPS		0x00000080
 #define UARTCTRL_DOZEEN		0x00000040
 #define UARTCTRL_RSRC		0x00000020
@@ -1523,7 +1525,7 @@ static void lpuart32_setup_watermark(struct lpuart_port *sport)
 	ctrl = lpuart32_read(&sport->port, UARTCTRL);
 	ctrl_saved = ctrl;
 	ctrl &= ~(UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_TE |
-			UARTCTRL_RIE | UARTCTRL_RE);
+			UARTCTRL_RIE | UARTCTRL_RE | UARTCTRL_ILIE);
 	lpuart32_write(&sport->port, ctrl, UARTCTRL);
 
 	/* enable FIFO mode */
@@ -1547,7 +1549,8 @@ static void lpuart32_setup_watermark_enable(struct lpuart_port *sport)
 	lpuart32_setup_watermark(sport);
 
 	temp = lpuart32_read(&sport->port, UARTCTRL);
-	temp |= UARTCTRL_RE | UARTCTRL_TE | UARTCTRL_ILIE;
+	temp |= UARTCTRL_RE | UARTCTRL_TE;
+	temp |= FIELD_PREP(UARTCTRL_IDLECFG, 0x7);
 	lpuart32_write(&sport->port, temp, UARTCTRL);
 }
 
@@ -1691,7 +1694,7 @@ static void lpuart32_configure(struct lpuart_port *sport)
 	}
 	temp = lpuart32_read(&sport->port, UARTCTRL);
 	if (!sport->lpuart_dma_rx_use)
-		temp |= UARTCTRL_RIE;
+		temp |= UARTCTRL_RIE | UARTCTRL_ILIE;
 	if (!sport->lpuart_dma_tx_use)
 		temp |= UARTCTRL_TIE;
 	lpuart32_write(&sport->port, temp, UARTCTRL);
@@ -1798,7 +1801,7 @@ static void lpuart32_shutdown(struct uart_port *port)
 
 	/* disable Rx/Tx and interrupts */
 	temp = lpuart32_read(port, UARTCTRL);
-	temp &= ~(UARTCTRL_TE | UARTCTRL_RE |
+	temp &= ~(UARTCTRL_TE | UARTCTRL_RE | UARTCTRL_ILIE |
 			UARTCTRL_TIE | UARTCTRL_TCIE | UARTCTRL_RIE);
 	lpuart32_write(port, temp, UARTCTRL);