Commit 740165f7 authored by Jiri Slaby's avatar Jiri Slaby Committed by Greg Kroah-Hartman
Browse files

mxser: introduce and use start/stop_tx helpers 



Starting and stopping TX is performed on many places in the driver. It
is repeated outb and info->IER modification.  Create few helpers
(__mxser_start_tx, mxser_start_tx, __mxser_stop_tx) and use them in the
code instead of open coding.

This should be a base for an uart driver for this device in the future.

Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-60-jslaby@suse.cz


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent be486667

drivers/tty/mxser.c

+37 −43
Original line number Diff line number Diff line
@@ -418,6 +418,28 @@ static void mxser_process_txrx_fifo(struct mxser_port *info) 
		}

}



static void __mxser_start_tx(struct mxser_port *info)

{

	outb(info->IER & ~UART_IER_THRI, info->ioaddr + UART_IER);

	info->IER |= UART_IER_THRI;

	outb(info->IER, info->ioaddr + UART_IER);

}



static void mxser_start_tx(struct mxser_port *info)

{

	unsigned long flags;



	spin_lock_irqsave(&info->slock, flags);

	__mxser_start_tx(info);

	spin_unlock_irqrestore(&info->slock, flags);

}



static void __mxser_stop_tx(struct mxser_port *info)

{

	info->IER &= ~UART_IER_THRI;

	outb(info->IER, info->ioaddr + UART_IER);

}



static int mxser_carrier_raised(struct tty_port *port)

{

	struct mxser_port *mp = container_of(port, struct mxser_port, port);
@@ -516,12 +538,8 @@ static void mxser_handle_cts(struct tty_struct *tty, struct mxser_port *info, 
			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);

			}

					!info->board->must_hwid)

				__mxser_start_tx(info);

			tty_wakeup(tty);

		}

		return;
@@ -529,10 +547,8 @@ static void mxser_handle_cts(struct tty_struct *tty, struct mxser_port *info, 
		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);

	}

	if (info->type != PORT_16550A && !info->board->must_hwid)

		__mxser_stop_tx(info);

}



/*
@@ -947,16 +963,9 @@ static int mxser_write(struct tty_struct *tty, const unsigned char *buf, int cou 
	}



	if (info->xmit_cnt && !tty->flow.stopped) {

		if (!tty->hw_stopped ||

				(info->type == PORT_16550A) ||

				(info->board->must_hwid)) {

			spin_lock_irqsave(&info->slock, flags);

			outb(info->IER & ~UART_IER_THRI, info->ioaddr +

					UART_IER);

			info->IER |= UART_IER_THRI;

			outb(info->IER, info->ioaddr + UART_IER);

			spin_unlock_irqrestore(&info->slock, flags);

		}

		if (!tty->hw_stopped || info->type == PORT_16550A ||

				info->board->must_hwid)

			mxser_start_tx(info);

	}

	return total;

}
@@ -985,20 +994,13 @@ static int mxser_put_char(struct tty_struct *tty, unsigned char ch) 
static void mxser_flush_chars(struct tty_struct *tty)

{

	struct mxser_port *info = tty->driver_data;

	unsigned long flags;



	if (info->xmit_cnt <= 0 || tty->flow.stopped || !info->port.xmit_buf ||

			(tty->hw_stopped && info->type != PORT_16550A &&

			 !info->board->must_hwid))

		return;



	spin_lock_irqsave(&info->slock, flags);



	outb(info->IER & ~UART_IER_THRI, info->ioaddr + UART_IER);

	info->IER |= UART_IER_THRI;

	outb(info->IER, info->ioaddr + UART_IER);



	spin_unlock_irqrestore(&info->slock, flags);

	mxser_start_tx(info);

}



static unsigned int mxser_write_room(struct tty_struct *tty)
@@ -1399,10 +1401,8 @@ static void mxser_stop(struct tty_struct *tty) 
	unsigned long flags;



	spin_lock_irqsave(&info->slock, flags);

	if (info->IER & UART_IER_THRI) {

		info->IER &= ~UART_IER_THRI;

		outb(info->IER, info->ioaddr + UART_IER);

	}

	if (info->IER & UART_IER_THRI)

		__mxser_stop_tx(info);

	spin_unlock_irqrestore(&info->slock, flags);

}
@@ -1412,11 +1412,8 @@ static void mxser_start(struct tty_struct *tty) 
	unsigned long flags;



	spin_lock_irqsave(&info->slock, flags);

	if (info->xmit_cnt && info->port.xmit_buf) {

		outb(info->IER & ~UART_IER_THRI, info->ioaddr + UART_IER);

		info->IER |= UART_IER_THRI;

		outb(info->IER, info->ioaddr + UART_IER);

	}

	if (info->xmit_cnt && info->port.xmit_buf)

		__mxser_start_tx(info);

	spin_unlock_irqrestore(&info->slock, flags);

}
@@ -1659,8 +1656,7 @@ static void mxser_transmit_chars(struct tty_struct *tty, struct mxser_port *port 
			(tty->hw_stopped &&

			(port->type != PORT_16550A) &&

			(!port->board->must_hwid))) {

		port->IER &= ~UART_IER_THRI;

		outb(port->IER, port->ioaddr + UART_IER);

		__mxser_stop_tx(port);

		return;

	}
@@ -1679,10 +1675,8 @@ static void mxser_transmit_chars(struct tty_struct *tty, struct mxser_port *port 
	if (port->xmit_cnt < WAKEUP_CHARS)

		tty_wakeup(tty);



	if (port->xmit_cnt <= 0) {

		port->IER &= ~UART_IER_THRI;

		outb(port->IER, port->ioaddr + UART_IER);

	}

	if (port->xmit_cnt <= 0)

		__mxser_stop_tx(port);

}



static bool mxser_port_isr(struct mxser_port *port)