Commit d249e662 authored by Jiri Slaby's avatar Jiri Slaby Committed by Greg Kroah-Hartman
Browse files

mxser: store FCR state in mxser_port::FCR 



We force the FCR contents on many places in the code instead of writing
what was actually set in mxser_change_speed() (by ->activate() or
->set_serial_info()).

So introduce mxser_port::FCR to hold the proper contents and bitwise-OR
the value to what needs to be set on all those locations. That is,
clearing RX and/or TX FIFOs. Those flags are self-clearing, so no need
to set them to mxser_port::FCR.

Signed-off-by: default avatarJiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210922075938.31390-7-jslaby@suse.cz


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 215fa41c

drivers/tty/mxser.c

+13 −14
Original line number Diff line number Diff line
@@ -249,6 +249,7 @@ struct mxser_port { 
	unsigned char x_char;	/* xon/xoff character */

	u8 IER;			/* Interrupt Enable Register */

	u8 MCR;			/* Modem control register */

	u8 FCR;			/* FIFO control register */



	bool ldisc_stop_rx;
@@ -562,7 +563,7 @@ static void mxser_handle_cts(struct tty_struct *tty, struct mxser_port *info, 
static void mxser_change_speed(struct tty_struct *tty, struct ktermios *old_termios)

{

	struct mxser_port *info = tty->driver_data;

	unsigned cflag, cval, fcr;

	unsigned cflag, cval;



	cflag = tty->termios.c_cflag;
@@ -600,25 +601,25 @@ static void mxser_change_speed(struct tty_struct *tty, struct ktermios *old_term 
	if (cflag & CMSPAR)

		cval |= UART_LCR_SPAR;



	fcr = 0;

	info->FCR = 0;

	if (info->board->must_hwid) {

		fcr |= UART_FCR_ENABLE_FIFO |

		info->FCR |= UART_FCR_ENABLE_FIFO |

			MOXA_MUST_FCR_GDA_MODE_ENABLE;

		mxser_set_must_fifo_value(info);

	} else if (info->type != PORT_8250 && info->type != PORT_16450) {

		fcr |= UART_FCR_ENABLE_FIFO;

		info->FCR |= UART_FCR_ENABLE_FIFO;

		switch (info->rx_high_water) {

		case 1:

			fcr |= UART_FCR_TRIGGER_1;

			info->FCR |= UART_FCR_TRIGGER_1;

			break;

		case 4:

			fcr |= UART_FCR_TRIGGER_4;

			info->FCR |= UART_FCR_TRIGGER_4;

			break;

		case 8:

			fcr |= UART_FCR_TRIGGER_8;

			info->FCR |= UART_FCR_TRIGGER_8;

			break;

		default:

			fcr |= UART_FCR_TRIGGER_14;

			info->FCR |= UART_FCR_TRIGGER_14;

			break;

		}

	}
@@ -679,7 +680,7 @@ static void mxser_change_speed(struct tty_struct *tty, struct ktermios *old_term 
	}





	outb(fcr, info->ioaddr + UART_FCR);	/* set fcr */

	outb(info->FCR, info->ioaddr + UART_FCR);

	outb(cval, info->ioaddr + UART_LCR);

}
@@ -865,7 +866,7 @@ static void mxser_flush_buffer(struct tty_struct *tty) 
	spin_lock_irqsave(&info->slock, flags);

	info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;



	outb(UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,

	outb(info->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,

		info->ioaddr + UART_FCR);



	spin_unlock_irqrestore(&info->slock, flags);
@@ -1572,8 +1573,7 @@ static u8 mxser_receive_chars_old(struct tty_struct *tty, 


		ch = inb(port->ioaddr + UART_RX);

		if (hwid && (status & UART_LSR_OE))

			outb(UART_FCR_ENABLE_FIFO | UART_FCR_CLEAR_RCVR |

					MOXA_MUST_FCR_GDA_MODE_ENABLE,

			outb(port->FCR | UART_FCR_CLEAR_RCVR,

					port->ioaddr + UART_FCR);

		status &= port->read_status_mask;

		if (status & port->ignore_status_mask) {
@@ -1685,8 +1685,7 @@ static bool mxser_port_isr(struct mxser_port *port) 
	tty = tty_port_tty_get(&port->port);

	if (!tty || port->closing || !tty_port_initialized(&port->port)) {

		status = inb(port->ioaddr + UART_LSR);

		outb(MOXA_MUST_FCR_GDA_MODE_ENABLE | UART_FCR_ENABLE_FIFO |

				UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,

		outb(port->FCR | UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT,

				port->ioaddr + UART_FCR);

		inb(port->ioaddr + UART_MSR);