Commit 92cc9d1d authored by Jiri Slaby's avatar Jiri Slaby Committed by Greg Kroah-Hartman
Browse files

mxser: use tty_port xmit_buf helpers 



For the mxser driver to use kfifo, use tty_port_alloc_xmit_buf() and
tty_port_free_xmit_buf() helpers in activate/shutdown, respectively.

As these calls have to be done in a non-atomic context, we have to move
them outside spinlock and make sure irq is really stopped after we write
to the ISR register.

Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220124071430.14907-7-jslaby@suse.cz


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent cd3a4907

drivers/tty/mxser.c

+9 −15
Original line number Diff line number Diff line
@@ -742,13 +742,12 @@ static void mxser_disable_and_clear_FIFO(struct mxser_port *info) 
static int mxser_activate(struct tty_port *port, struct tty_struct *tty)

{

	struct mxser_port *info = container_of(port, struct mxser_port, port);

	unsigned long page;

	unsigned long flags;

	int ret;



	page = __get_free_page(GFP_KERNEL);

	if (!page)

		return -ENOMEM;

	ret = tty_port_alloc_xmit_buf(port);

	if (ret < 0)

		return ret;



	spin_lock_irqsave(&info->slock, flags);
@@ -758,7 +757,6 @@ static int mxser_activate(struct tty_port *port, struct tty_struct *tty) 
		ret = 0;

		goto err_free_xmit;

	}

	info->port.xmit_buf = (unsigned char *) page;



	/*

	 * Clear the FIFO buffers and disable them
@@ -825,8 +823,7 @@ static int mxser_activate(struct tty_port *port, struct tty_struct *tty) 


	return 0;

err_free_xmit:

	free_page(page);

	info->port.xmit_buf = NULL;

	tty_port_free_xmit_buf(port);

	return ret;

}
@@ -862,14 +859,6 @@ static void mxser_shutdown_port(struct tty_port *port) 
	 */

	wake_up_interruptible(&info->port.delta_msr_wait);



	/*

	 * Free the xmit buffer, if necessary

	 */

	if (info->port.xmit_buf) {

		free_page((unsigned long) info->port.xmit_buf);

		info->port.xmit_buf = NULL;

	}



	info->IER = 0;

	outb(0x00, info->ioaddr + UART_IER);
@@ -884,6 +873,11 @@ static void mxser_shutdown_port(struct tty_port *port) 
		mxser_must_no_sw_flow_control(info->ioaddr);



	spin_unlock_irqrestore(&info->slock, flags);



	/* make sure ISR is not running while we free the buffer */

	synchronize_irq(info->board->irq);



	tty_port_free_xmit_buf(port);

}



/*