mxser: extract and dedup CTS handling

CTS is handled on two locations in mxser. Extract the code into
separation function mxser_handle_cts. And call it from the two
locations.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-59-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 52dbdd4282b2523a79bff894fa762118bc7c8bb5..00363d98277ecc45196adb65c2497448182d5f1f 100644 (file)
--- a/drivers/tty/mxser.c
+++ b/drivers/tty/mxser.c
@@ -506,6 +506,35 @@ static int mxser_set_baud(struct tty_struct *tty, speed_t newspd)
        return 0;
 }
 
+static void mxser_handle_cts(struct tty_struct *tty, struct mxser_port *info,
+               u8 msr)
+{
+       bool cts = msr & UART_MSR_CTS;
+
+       if (tty->hw_stopped) {
+               if (cts) {
+                       tty->hw_stopped = 0;
+
+                       if (info->type != PORT_16550A &&
+                                       !info->board->must_hwid) {
+                               outb(info->IER & ~UART_IER_THRI,
+                                       info->ioaddr + UART_IER);
+                               info->IER |= UART_IER_THRI;
+                               outb(info->IER, info->ioaddr + UART_IER);
+                       }
+                       tty_wakeup(tty);
+               }
+               return;
+       } else if (cts)
+               return;
+
+       tty->hw_stopped = 1;
+       if (info->type != PORT_16550A && !info->board->must_hwid) {
+               info->IER &= ~UART_IER_THRI;
+               outb(info->IER, info->ioaddr + UART_IER);
+       }
+}
+
 /*
  * This routine is called to set the UART divisor registers to match
  * the specified baud rate for a serial port.
@@ -514,7 +543,6 @@ static void mxser_change_speed(struct tty_struct *tty)
 {
        struct mxser_port *info = tty->driver_data;
        unsigned cflag, cval, fcr;
-       unsigned char status;
 
        cflag = tty->termios.c_cflag;
 
@@ -585,32 +613,8 @@ static void mxser_change_speed(struct tty_struct *tty)
                if ((info->type == PORT_16550A) || (info->board->must_hwid)) {
                        info->MCR |= UART_MCR_AFE;
                } else {
-                       status = inb(info->ioaddr + UART_MSR);
-                       if (tty->hw_stopped) {
-                               if (status & UART_MSR_CTS) {
-                                       tty->hw_stopped = 0;
-                                       if (info->type != PORT_16550A &&
-                                                       !info->board->must_hwid) {
-                                               outb(info->IER & ~UART_IER_THRI,
-                                                       info->ioaddr +
-                                                       UART_IER);
-                                               info->IER |= UART_IER_THRI;
-                                               outb(info->IER, info->ioaddr +
-                                                               UART_IER);
-                                       }
-                                       tty_wakeup(tty);
-                               }
-                       } else {
-                               if (!(status & UART_MSR_CTS)) {
-                                       tty->hw_stopped = 1;
-                                       if ((info->type != PORT_16550A) &&
-                                                       (!info->board->must_hwid)) {
-                                               info->IER &= ~UART_IER_THRI;
-                                               outb(info->IER, info->ioaddr +
-                                                               UART_IER);
-                                       }
-                               }
-                       }
+                       mxser_handle_cts(tty, info,
+                                       inb(info->ioaddr + UART_MSR));
                }
        }
        outb(info->MCR, info->ioaddr + UART_MCR);
@@ -679,33 +683,8 @@ static void mxser_check_modem_status(struct tty_struct *tty,
                        wake_up_interruptible(&port->port.open_wait);
        }
 
-       if (tty_port_cts_enabled(&port->port)) {
-               if (tty->hw_stopped) {
-                       if (status & UART_MSR_CTS) {
-                               tty->hw_stopped = 0;
-
-                               if ((port->type != PORT_16550A) &&
-                                               (!port->board->must_hwid)) {
-                                       outb(port->IER & ~UART_IER_THRI,
-                                               port->ioaddr + UART_IER);
-                                       port->IER |= UART_IER_THRI;
-                                       outb(port->IER, port->ioaddr +
-                                                       UART_IER);
-                               }
-                               tty_wakeup(tty);
-                       }
-               } else {
-                       if (!(status & UART_MSR_CTS)) {
-                               tty->hw_stopped = 1;
-                               if (port->type != PORT_16550A &&
-                                               !port->board->must_hwid) {
-                                       port->IER &= ~UART_IER_THRI;
-                                       outb(port->IER, port->ioaddr +
-                                                       UART_IER);
-                               }
-                       }
-               }
-       }
+       if (tty_port_cts_enabled(&port->port))
+               mxser_handle_cts(tty, port, status);
 }
 
 static int mxser_activate(struct tty_port *port, struct tty_struct *tty)