From:   Jiri Slaby <jslaby@suse.cz>
To:     gregkh@linuxfoundation.org
Cc:     linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jiri Slaby <jslaby@suse.cz>
Subject: [PATCH 05/19] mxser: clean up tx handling in mxser_transmit_chars()
Date:   Thu, 18 Nov 2021 08:31:11 +0100
Message-Id: <20211118073125.12283-6-jslaby@suse.cz>
In-Reply-To: <20211118073125.12283-1-jslaby@suse.cz>
References: <20211118073125.12283-1-jslaby@suse.cz>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

The port->icount.tx is handled in a too complicated manner. Instead of
remembering the original count and subtracting the new one from it,
simply increase tx for each character in the loop. No need for cnt
variable then.

Change also the "X = X & Y" assignment to simpler "X &= Y".

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 drivers/tty/mxser.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 3d5c20e31836..eb5fb4fb2aef 100644
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -1622,7 +1622,7 @@ static u8 mxser_receive_chars(struct tty_struct *tty,
 
 static void mxser_transmit_chars(struct tty_struct *tty, struct mxser_port *port)
 {
-	int count, cnt;
+	int count;
 
 	if (port->x_char) {
 		outb(port->x_char, port->ioaddr + UART_TX);
@@ -1640,18 +1640,16 @@ static void mxser_transmit_chars(struct tty_struct *tty, struct mxser_port *port
 		return;
 	}
 
-	cnt = port->xmit_cnt;
 	count = port->xmit_fifo_size;
 	do {
 		outb(port->port.xmit_buf[port->xmit_tail++],
 			port->ioaddr + UART_TX);
-		port->xmit_tail = port->xmit_tail & (SERIAL_XMIT_SIZE - 1);
+		port->xmit_tail &= SERIAL_XMIT_SIZE - 1;
+		port->icount.tx++;
 		if (!--port->xmit_cnt)
 			break;
 	} while (--count > 0);
 
-	port->icount.tx += (cnt - port->xmit_cnt);
-
 	if (port->xmit_cnt < WAKEUP_CHARS)
 		tty_wakeup(tty);
 
-- 
2.33.1