diff options
author | Joe Perches <joe@perches.com> | 2013-01-28 06:21:00 +0400 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-01-30 09:09:58 +0400 |
commit | 9fe8074b82ed14358be50c62ab9d081bcb911607 (patch) | |
tree | 53dd1345c50b76426747536bb681489f59aaa93f /drivers/tty/synclink.c | |
parent | abd7bacae672298ec99ce6cfdc75ae1e1f9159b6 (diff) | |
download | linux-9fe8074b82ed14358be50c62ab9d081bcb911607.tar.xz |
TTY: synclink: Convert + to | for bit operations
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>
Diffstat (limited to 'drivers/tty/synclink.c')
-rw-r--r-- | drivers/tty/synclink.c | 26 |
1 files changed, 13 insertions, 13 deletions
diff --git a/drivers/tty/synclink.c b/drivers/tty/synclink.c index 555fdc0ed0f1..8983276aa35e 100644 --- a/drivers/tty/synclink.c +++ b/drivers/tty/synclink.c @@ -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 */ |