mxser: clean up tx handling in mxser_transmit_chars()

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>
Link: https://lore.kernel.org/r/20211118073125.12283-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/tty/mxser.c b/drivers/tty/mxser.c
index 3d5c20e3183637612db9277dcfa098962d02dac2..eb5fb4fb2aefa649fdf192db440e2ec8f7aafa92 100644 (file)
--- 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);