Re: [patch] TTY: synclink, small cleanup in dtr_rts()

Joe Perches
2013-01-27T20:04:46Z

On Sun, 2013-01-27 at 22:40 +0300, Dan Carpenter wrote:
> 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.

Wouldn't it be clearer still to use | instead of +

> diff --git a/drivers/char/pcmcia/synclink_cs.c b/drivers/char/pcmcia/synclink_cs.c
[]
> @@ -2466,7 +2466,7 @@ static void dtr_rts(struct tty_port *port, int onoff)
> if (onoff)
> info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
> else
> - info->serial_signals &= ~SerialSignal_RTS + SerialSignal_DTR;
> + info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);

drivers/tty/synclink.c | 16 ++++++++--------
drivers/tty/synclink_gt.c | 18 +++++++++---------
drivers/tty/synclinkmp.c | 18 +++++++++---------
3 files changed, 26 insertions(+), 26 deletions(-)

diff --git a/drivers/tty/synclink.c b/drivers/tty/synclink.c
index 555fdc0..636ef3e 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_DTR | SerialSignal_RTS);
usc_set_serial_signals(info);
}

@@ -1918,9 +1918,9 @@ static void mgsl_change_params(struct mgsl_struct *info)
/* if B0 rate (hangup) specified then negate DTR and RTS */
/* otherwise assert DTR and RTS */
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);
}
@@ -6240,7 +6240,7 @@ 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;
+ info->serial_signals &= SerialSignal_DTR | SerialSignal_RTS;

/* Read the Misc Interrupt status Register (MISR) to get */
/* the V24 status signals. */
@@ -7780,7 +7780,7 @@ static int hdlcdev_open(struct net_device *dev)
}

/* assert DTR and RTS, apply hardware settings */
- info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+ info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
mgsl_program_hw(info);

/* enable network layer transmit */
diff --git a/drivers/tty/synclink_gt.c b/drivers/tty/synclink_gt.c
index ac8599a..a66539c 100644
--- a/drivers/tty/synclink_gt.c
+++ b/drivers/tty/synclink_gt.c
@@ -785,7 +785,7 @@ static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
/* Handle transition to B0 status */
if (old_termios->c_cflag & CBAUD &&
!(tty->termios.c_cflag & CBAUD)) {
- info->signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+ info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
spin_lock_irqsave(&info->lock,flags);
set_signals(info);
spin_unlock_irqrestore(&info->lock,flags);
@@ -1561,7 +1561,7 @@ static int hdlcdev_open(struct net_device *dev)
}

/* assert DTR and RTS, apply hardware settings */
- info->signals |= SerialSignal_RTS + SerialSignal_DTR;
+ info->signals |= SerialSignal_RTS | SerialSignal_DTR;
program_hw(info);

/* enable network layer transmit */
@@ -2488,7 +2488,7 @@ static void shutdown(struct slgt_info *info)
slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);

if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
- info->signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+ info->signals &= ~(SerialSignal_DTR | SerialSignal_RTS);
set_signals(info);
}

@@ -2551,9 +2551,9 @@ static void change_params(struct slgt_info *info)
/* if B0 rate (hangup) specified then negate DTR and RTS */
/* otherwise assert DTR and RTS */
if (cflag & CBAUD)
- info->signals |= SerialSignal_RTS + SerialSignal_DTR;
+ info->signals |= SerialSignal_RTS | SerialSignal_DTR;
else
- info->signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+ info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);

/* byte size and parity */

@@ -3256,9 +3256,9 @@ static void dtr_rts(struct tty_port *port, int on)

spin_lock_irqsave(&info->lock,flags);
if (on)
- info->signals |= SerialSignal_RTS + SerialSignal_DTR;
+ info->signals |= SerialSignal_RTS | SerialSignal_DTR;
else
- info->signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
+ info->signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
set_signals(info);
spin_unlock_irqrestore(&info->lock,flags);
}
@@ -4119,7 +4119,7 @@ static void reset_port(struct slgt_info *info)
tx_stop(info);
rx_stop(info);

- info->signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+ info->signals &= ~(SerialSignal_DTR | SerialSignal_RTS);
set_signals(info);

slgt_irq_off(info, IRQ_ALL | IRQ_MASTER);
@@ -4547,7 +4547,7 @@ static void get_signals(struct slgt_info *info)
unsigned short status = rd_reg16(info, SSR);

/* clear all serial signals except DTR and RTS */
- info->signals &= SerialSignal_DTR + SerialSignal_RTS;
+ info->signals &= SerialSignal_DTR | SerialSignal_RTS;

if (status & BIT3)
info->signals |= SerialSignal_DSR;
diff --git a/drivers/tty/synclinkmp.c b/drivers/tty/synclinkmp.c
index 5454025..620b1da 100644
--- a/drivers/tty/synclinkmp.c
+++ b/drivers/tty/synclinkmp.c
@@ -882,7 +882,7 @@ static void set_termios(struct tty_struct *tty, struct ktermios *old_termios)
/* 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->lock,flags);
set_signals(info);
spin_unlock_irqrestore(&info->lock,flags);
@@ -1677,7 +1677,7 @@ static int hdlcdev_open(struct net_device *dev)
}

/* assert DTR and RTS, apply hardware settings */
- info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
+ info->serial_signals |= SerialSignal_RTS | SerialSignal_DTR;
program_hw(info);

/* enable network layer transmit */
@@ -2706,7 +2706,7 @@ static void shutdown(SLMP_INFO * info)
reset_port(info);

if (!info->port.tty || info->port.tty->termios.c_cflag & HUPCL) {
- info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+ info->serial_signals &= ~(SerialSignal_DTR | SerialSignal_RTS);
set_signals(info);
}

@@ -2771,9 +2771,9 @@ static void change_params(SLMP_INFO *info)
/* if B0 rate (hangup) specified then negate DTR and RTS */
/* otherwise assert DTR and RTS */
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 */

@@ -3272,9 +3272,9 @@ static void dtr_rts(struct tty_port *port, int on)

spin_lock_irqsave(&info->lock,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);
set_signals(info);
spin_unlock_irqrestore(&info->lock,flags);
}
@@ -4354,7 +4354,7 @@ static void reset_port(SLMP_INFO *info)
tx_stop(info);
rx_stop(info);

- info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+ info->serial_signals &= ~(SerialSignal_DTR | SerialSignal_RTS);
set_signals(info);

/* disable all port interrupts */
@@ -4751,7 +4751,7 @@ static void get_signals(SLMP_INFO *info)
u16 testbit;

/* clear all serial signals except DTR and RTS */
- info->serial_signals &= SerialSignal_DTR + SerialSignal_RTS;
+ info->serial_signals &= SerialSignal_DTR | SerialSignal_RTS;

/* set serial signal bits to reflect MISR */