Commit a58e00e7 authored by Jesper Juhl's avatar Jesper Juhl Committed by Linus Torvalds
Browse files

[PATCH] Decrease number of pointer derefs in jsm_tty.c 



Decrease the number of pointer derefs in drivers/serial/jsm/jsm_tty.c

Benefits of the patch:
 - Fewer pointer dereferences should make the code slightly faster.
 - Size of generated code is smaller
 - Improved readability

Signed-off-by: default avatarJesper Juhl <jesper.juhl@gmail.com>
Acked-by: default avatar"V. ANANDA KRISHNAN" <mansarov@us.ibm.com>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent a244e169

drivers/serial/jsm/jsm_tty.c

+17 −12
Original line number Diff line number Diff line
@@ -142,12 +142,14 @@ static void jsm_tty_send_xchar(struct uart_port *port, char ch) 
{

	unsigned long lock_flags;

	struct jsm_channel *channel = (struct jsm_channel *)port;

	struct termios *termios;



	spin_lock_irqsave(&port->lock, lock_flags);

	if (ch == port->info->tty->termios->c_cc[VSTART])

	termios = port->info->tty->termios;

	if (ch == termios->c_cc[VSTART])

		channel->ch_bd->bd_ops->send_start_character(channel);



	if (ch == port->info->tty->termios->c_cc[VSTOP])

	if (ch == termios->c_cc[VSTOP])

		channel->ch_bd->bd_ops->send_stop_character(channel);

	spin_unlock_irqrestore(&port->lock, lock_flags);

}
@@ -178,6 +180,7 @@ static int jsm_tty_open(struct uart_port *port) 
	struct jsm_board *brd;

	int rc = 0;

	struct jsm_channel *channel = (struct jsm_channel *)port;

	struct termios *termios;



	/* Get board pointer from our array of majors we have allocated */

	brd = channel->ch_bd;
@@ -239,12 +242,13 @@ static int jsm_tty_open(struct uart_port *port) 
	channel->ch_cached_lsr = 0;

	channel->ch_stops_sent = 0;



	channel->ch_c_cflag	= port->info->tty->termios->c_cflag;

	channel->ch_c_iflag	= port->info->tty->termios->c_iflag;

	channel->ch_c_oflag	= port->info->tty->termios->c_oflag;

	channel->ch_c_lflag	= port->info->tty->termios->c_lflag;

	channel->ch_startc = port->info->tty->termios->c_cc[VSTART];

	channel->ch_stopc = port->info->tty->termios->c_cc[VSTOP];

	termios = port->info->tty->termios;

	channel->ch_c_cflag	= termios->c_cflag;

	channel->ch_c_iflag	= termios->c_iflag;

	channel->ch_c_oflag	= termios->c_oflag;

	channel->ch_c_lflag	= termios->c_lflag;

	channel->ch_startc	= termios->c_cc[VSTART];

	channel->ch_stopc	= termios->c_cc[VSTOP];



	/* Tell UART to init itself */

	brd->bd_ops->uart_init(channel);
@@ -784,6 +788,7 @@ static void jsm_carrier(struct jsm_channel *ch) 


void jsm_check_queue_flow_control(struct jsm_channel *ch)

{

	struct board_ops *bd_ops = ch->ch_bd->bd_ops;

	int qleft = 0;



	/* Store how much space we have left in the queue */
@@ -809,7 +814,7 @@ void jsm_check_queue_flow_control(struct jsm_channel *ch) 
		/* HWFLOW */

		if (ch->ch_c_cflag & CRTSCTS) {

			if(!(ch->ch_flags & CH_RECEIVER_OFF)) {

				ch->ch_bd->bd_ops->disable_receiver(ch);

				bd_ops->disable_receiver(ch);

				ch->ch_flags |= (CH_RECEIVER_OFF);

				jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,

					"Internal queue hit hilevel mark (%d)! Turning off interrupts.\n",
@@ -819,7 +824,7 @@ void jsm_check_queue_flow_control(struct jsm_channel *ch) 
		/* SWFLOW */

		else if (ch->ch_c_iflag & IXOFF) {

			if (ch->ch_stops_sent <= MAX_STOPS_SENT) {

				ch->ch_bd->bd_ops->send_stop_character(ch);

				bd_ops->send_stop_character(ch);

				ch->ch_stops_sent++;

				jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,

					"Sending stop char! Times sent: %x\n", ch->ch_stops_sent);
@@ -846,7 +851,7 @@ void jsm_check_queue_flow_control(struct jsm_channel *ch) 
		/* HWFLOW */

		if (ch->ch_c_cflag & CRTSCTS) {

			if (ch->ch_flags & CH_RECEIVER_OFF) {

				ch->ch_bd->bd_ops->enable_receiver(ch);

				bd_ops->enable_receiver(ch);

				ch->ch_flags &= ~(CH_RECEIVER_OFF);

				jsm_printk(READ, INFO, &ch->ch_bd->pci_dev,

					"Internal queue hit lowlevel mark (%d)! Turning on interrupts.\n",
@@ -856,7 +861,7 @@ void jsm_check_queue_flow_control(struct jsm_channel *ch) 
		/* SWFLOW */

		else if (ch->ch_c_iflag & IXOFF && ch->ch_stops_sent) {

			ch->ch_stops_sent = 0;

			ch->ch_bd->bd_ops->send_start_character(ch);

			bd_ops->send_start_character(ch);

			jsm_printk(READ, INFO, &ch->ch_bd->pci_dev, "Sending start char!\n");

		}

	}

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