mxser: move MSR read to mxser_check_modem_status()

The MSR read is currently performed on both places where
mxser_check_modem_status() is called. So move it there to avoid code
duplication.

Rename the variable to msr while we move it, to actually see what
"status" we are testing.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20211118073125.12283-5-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 c8a56b0d900d31e6080dea0a6223518abe533495..3d5c20e3183637612db9277dcfa098962d02dac2 100644 (file)
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -683,27 +683,34 @@ static void mxser_change_speed(struct tty_struct *tty, struct ktermios *old_term
        outb(cval, info->ioaddr + UART_LCR);
 }
 
-static void mxser_check_modem_status(struct tty_struct *tty,
-                               struct mxser_port *port, int status)
+static u8 mxser_check_modem_status(struct tty_struct *tty,
+                               struct mxser_port *port)
 {
+       u8 msr = inb(port->ioaddr + UART_MSR);
+
+       if (!(msr & UART_MSR_ANY_DELTA))
+               return msr;
+
        /* update input line counters */
-       if (status & UART_MSR_TERI)
+       if (msr & UART_MSR_TERI)
                port->icount.rng++;
-       if (status & UART_MSR_DDSR)
+       if (msr & UART_MSR_DDSR)
                port->icount.dsr++;
-       if (status & UART_MSR_DDCD)
+       if (msr & UART_MSR_DDCD)
                port->icount.dcd++;
-       if (status & UART_MSR_DCTS)
+       if (msr & UART_MSR_DCTS)
                port->icount.cts++;
        wake_up_interruptible(&port->port.delta_msr_wait);
 
-       if (tty_port_check_carrier(&port->port) && (status & UART_MSR_DDCD)) {
-               if (status & UART_MSR_DCD)
+       if (tty_port_check_carrier(&port->port) && (msr & UART_MSR_DDCD)) {
+               if (msr & UART_MSR_DCD)
                        wake_up_interruptible(&port->port.open_wait);
        }
 
        if (tty_port_cts_enabled(&port->port))
-               mxser_handle_cts(tty, port, status);
+               mxser_handle_cts(tty, port, msr);
+
+       return msr;
 }
 
 static void mxser_disable_and_clear_FIFO(struct mxser_port *info)
@@ -1135,25 +1142,24 @@ static int mxser_get_lsr_info(struct mxser_port *info,
 static int mxser_tiocmget(struct tty_struct *tty)
 {
        struct mxser_port *info = tty->driver_data;
-       unsigned char control, status;
+       unsigned char control;
        unsigned long flags;
+       u8 msr;
 
        if (tty_io_error(tty))
                return -EIO;
 
        spin_lock_irqsave(&info->slock, flags);
        control = info->MCR;
-       status = inb(info->ioaddr + UART_MSR);
-       if (status & UART_MSR_ANY_DELTA)
-               mxser_check_modem_status(tty, info, status);
+       msr = mxser_check_modem_status(tty, info);
        spin_unlock_irqrestore(&info->slock, flags);
 
        return ((control & UART_MCR_RTS) ? TIOCM_RTS : 0) |
                    ((control & UART_MCR_DTR) ? TIOCM_DTR : 0) |
-                   ((status & UART_MSR_DCD) ? TIOCM_CAR : 0) |
-                   ((status & UART_MSR_RI) ? TIOCM_RNG : 0) |
-                   ((status & UART_MSR_DSR) ? TIOCM_DSR : 0) |
-                   ((status & UART_MSR_CTS) ? TIOCM_CTS : 0);
+                   ((msr & UART_MSR_DCD) ? TIOCM_CAR : 0) |
+                   ((msr & UART_MSR_RI) ? TIOCM_RNG : 0) |
+                   ((msr & UART_MSR_DSR) ? TIOCM_DSR : 0) |
+                   ((msr & UART_MSR_CTS) ? TIOCM_CTS : 0);
 }
 
 static int mxser_tiocmset(struct tty_struct *tty,
@@ -1656,7 +1662,7 @@ static void mxser_transmit_chars(struct tty_struct *tty, struct mxser_port *port
 static bool mxser_port_isr(struct mxser_port *port)
 {
        struct tty_struct *tty;
-       u8 iir, msr, status;
+       u8 iir, status;
        bool error = false;
 
        iir = inb(port->ioaddr + UART_IIR);
@@ -1689,9 +1695,7 @@ static bool mxser_port_isr(struct mxser_port *port)
                        status = mxser_receive_chars(tty, port, status);
        }
 
-       msr = inb(port->ioaddr + UART_MSR);
-       if (msr & UART_MSR_ANY_DELTA)
-               mxser_check_modem_status(tty, port, msr);
+       mxser_check_modem_status(tty, port);
 
        if (port->board->must_hwid) {
                if (iir == 0x02 && (status & UART_LSR_THRE))