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TTY: synclink: Convert + to | for bit operations

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Dan Carpenter noticed a missing set of parentheses
around a multiple field addition.

https://lkml.org/lkml/2013/1/27/166

His original commit message:

There is a kind of precedence problem here, but it doesn't affect how
the code works because ->serial_signals is unsigned char.  We want to
clear two flags here.

#define SerialSignal_RTS            0x20     /* Request to Send */
#define SerialSignal_DTR            0x80     /* Data Terminal Ready */

Without the parenthesis then it does:

	info->serial_signals &= 0x5f;

With the parenthesis it does:

	info->serial_signals &= 0xffffff5f;

info->serial_signals is an unsigned char so the two statements are
equivalent, but it's cleaner to add the parenthesis.  In other dtr_rts()
functions the parenthesis are there so this makes it more consistent.

Other changes:

Convert all + uses to | for these bit operations.

Reorder the multiple fields for consistency.
Update the comments too.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Joe Perches
2013-01-27 18:21:00 -08:00
committed by Greg Kroah-Hartman
parent abd7bacae6
commit 9fe8074b82
4 changed files with 59 additions and 59 deletions
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26
drivers/tty/synclink.c
View File

@@ -1850,7 +1850,7 @@ static void shutdown(struct mgsl_struct * info)
usc_OutReg(info, PCR, (u16)((usc_InReg(info, PCR) | BIT13) | BIT12));
if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
usc_set_serial_signals(info);
}
@@ -1915,12 +1915,12 @@ static void mgsl_change_params(struct mgsl_struct *info)
cflag = info->port.tty->termios.c_cflag;
/* if B0 rate (hangup) specified then negate DTR and RTS */
/* otherwise assert DTR and RTS */
/* if B0 rate (hangup) specified then negate RTS and DTR */
/* otherwise assert RTS and DTR */
if (cflag & CBAUD)
info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
else
info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
/* byte size and parity */
@@ -3044,7 +3044,7 @@ static void mgsl_set_termios(struct tty_struct *tty, struct ktermios *old_termio
/* Handle transition to B0 status */
if (old_termios->c_cflag & CBAUD &&
!(tty->termios.c_cflag & CBAUD)) {
info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
spin_lock_irqsave(&info->irq_spinlock,flags);
usc_set_serial_signals(info);
spin_unlock_irqrestore(&info->irq_spinlock,flags);
@@ -3243,9 +3243,9 @@ static void dtr_rts(struct tty_port *port, int on)
spin_lock_irqsave(&info->irq_spinlock,flags);
if (on)
info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
else
info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
usc_set_serial_signals(info);
spin_unlock_irqrestore(&info->irq_spinlock,flags);
}
@@ -6239,8 +6239,8 @@ static void usc_get_serial_signals( struct mgsl_struct *info )
{
u16 status;
/* clear all serial signals except DTR and RTS */
info->serial_signals &= SerialSignal_DTR + SerialSignal_RTS;
/* clear all serial signals except RTS and DTR */
info->serial_signals &= SerialSignal_RTS | SerialSignal_DTR;
/* Read the Misc Interrupt status Register (MISR) to get */
/* the V24 status signals. */
@@ -6265,7 +6265,7 @@ static void usc_get_serial_signals( struct mgsl_struct *info )
/* usc_set_serial_signals()
*
* Set the state of DTR and RTS based on contents of
* Set the state of RTS and DTR based on contents of
* serial_signals member of device extension.
*
* Arguments: info pointer to device instance data
@@ -7779,8 +7779,8 @@ static int hdlcdev_open(struct net_device *dev)
return rc;
}
/* assert DTR and RTS, apply hardware settings */
info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
/* assert RTS and DTR, apply hardware settings */
info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
mgsl_program_hw(info);
/* enable network layer transmit */