linux-kernel - [PATCH 40/70] mxser: dedup mxser_must_set_enhance

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Date:   Fri, 18 Jun 2021 08:14:46 +0200
From:   Jiri Slaby <jslaby@...e.cz>
To:     gregkh@...uxfoundation.org
Cc:     linux-serial@...r.kernel.org, linux-kernel@...r.kernel.org,
        Jiri Slaby <jslaby@...e.cz>
Subject: [PATCH 40/70] mxser: dedup mxser_must_set_enhance_mode

There are multiple copies of setting the EFR register. Separate it to a
new universal function called __mxser_must_set_EFR. And use it in the
code by introducing mxser_must_set_enhance_mode instead of
mxser_disable_must_enchance_mode and mxser_enable_must_enchance_mode.

Signed-off-by: Jiri Slaby <jslaby@...e.cz>
---
 drivers/tty/mxser.c | 42 ++++++++++++++++++++++--------------------
 1 file changed, 22 insertions(+), 20 deletions(-)

diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index e082ae055c39..7caf369571f1 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -314,34 +314,24 @@ struct mxser_board {
 static struct mxser_board mxser_boards[MXSER_BOARDS];
 static struct tty_driver *mxvar_sdriver;
 
-static void mxser_enable_must_enchance_mode(unsigned long baseio)
+static u8 __mxser_must_set_EFR(unsigned long baseio, u8 clear, u8 set,
+		bool restore_LCR)
 {
-	u8 oldlcr;
-	u8 efr;
+	u8 oldlcr, efr;
 
 	oldlcr = inb(baseio + UART_LCR);
 	outb(MOXA_MUST_ENTER_ENCHANCE, baseio + UART_LCR);
 
 	efr = inb(baseio + MOXA_MUST_EFR_REGISTER);
-	efr |= MOXA_MUST_EFR_EFRB_ENABLE;
+	efr &= ~clear;
+	efr |= set;
 
 	outb(efr, baseio + MOXA_MUST_EFR_REGISTER);
-	outb(oldlcr, baseio + UART_LCR);
-}
-
-static void mxser_disable_must_enchance_mode(unsigned long baseio)
-{
-	u8 oldlcr;
-	u8 efr;
-
-	oldlcr = inb(baseio + UART_LCR);
-	outb(MOXA_MUST_ENTER_ENCHANCE, baseio + UART_LCR);
 
-	efr = inb(baseio + MOXA_MUST_EFR_REGISTER);
-	efr &= ~MOXA_MUST_EFR_EFRB_ENABLE;
+	if (restore_LCR)
+		outb(oldlcr, baseio + UART_LCR);
 
-	outb(efr, baseio + MOXA_MUST_EFR_REGISTER);
-	outb(oldlcr, baseio + UART_LCR);
+	return oldlcr;
 }
 
 static void mxser_set_must_xon1_value(unsigned long baseio, u8 value)
@@ -431,6 +421,18 @@ static void mxser_get_must_hardware_id(unsigned long baseio, u8 *pId)
 	outb(oldlcr, baseio + UART_LCR);
 }
 
+static void mxser_must_set_EFR(unsigned long baseio, u8 clear, u8 set)
+{
+	__mxser_must_set_EFR(baseio, clear, set, true);
+}
+
+static void mxser_must_set_enhance_mode(unsigned long baseio, bool enable)
+{
+	mxser_must_set_EFR(baseio,
+			enable ? 0 : MOXA_MUST_EFR_EFRB_ENABLE,
+			enable ? MOXA_MUST_EFR_EFRB_ENABLE : 0);
+}
+
 static void SET_MOXA_MUST_NO_SOFTWARE_FLOW_CONTROL(unsigned long baseio)
 {
 	u8 oldlcr;
@@ -514,7 +516,7 @@ static enum mxser_must_hwid mxser_must_get_hwid(unsigned long io)
 	int i;
 
 	outb(0, io + UART_LCR);
-	mxser_disable_must_enchance_mode(io);
+	mxser_must_set_enhance_mode(io, false);
 	oldmcr = inb(io + UART_MCR);
 	outb(0, io + UART_MCR);
 	mxser_set_must_xon1_value(io, 0x11);
@@ -2011,7 +2013,7 @@ static int mxser_initbrd(struct mxser_board *brd)
 
 		/* Enhance mode enabled here */
 		if (brd->must_hwid != MOXA_OTHER_UART)
-			mxser_enable_must_enchance_mode(info->ioaddr);
+			mxser_must_set_enhance_mode(info->ioaddr, true);
 
 		info->type = PORT_16550A;
 
-- 
2.32.0