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>
diff --git a/drivers/tty/synclinkmp.c b/drivers/tty/synclinkmp.c
index 5454025..6d5780c 100644
--- a/drivers/tty/synclinkmp.c
+++ b/drivers/tty/synclinkmp.c
@@ -882,7 +882,7 @@
/* 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);
@@ -1676,8 +1676,8 @@
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;
program_hw(info);
/* enable network layer transmit */
@@ -2706,7 +2706,7 @@
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_RTS | SerialSignal_DTR);
set_signals(info);
}
@@ -2768,12 +2768,12 @@
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 */
@@ -3212,12 +3212,12 @@
get_signals(info);
spin_unlock_irqrestore(&info->lock,flags);
- result = ((info->serial_signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
- ((info->serial_signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
- ((info->serial_signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
- ((info->serial_signals & SerialSignal_RI) ? TIOCM_RNG:0) +
- ((info->serial_signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
- ((info->serial_signals & SerialSignal_CTS) ? TIOCM_CTS:0);
+ result = ((info->serial_signals & SerialSignal_RTS) ? TIOCM_RTS : 0) |
+ ((info->serial_signals & SerialSignal_DTR) ? TIOCM_DTR : 0) |
+ ((info->serial_signals & SerialSignal_DCD) ? TIOCM_CAR : 0) |
+ ((info->serial_signals & SerialSignal_RI) ? TIOCM_RNG : 0) |
+ ((info->serial_signals & SerialSignal_DSR) ? TIOCM_DSR : 0) |
+ ((info->serial_signals & SerialSignal_CTS) ? TIOCM_CTS : 0);
if (debug_level >= DEBUG_LEVEL_INFO)
printk("%s(%d):%s tiocmget() value=%08X\n",
@@ -3272,9 +3272,9 @@
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 @@
tx_stop(info);
rx_stop(info);
- info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
+ info->serial_signals &= ~(SerialSignal_RTS | SerialSignal_DTR);
set_signals(info);
/* disable all port interrupts */
@@ -4750,8 +4750,8 @@
u16 gpstatus = read_status_reg(info);
u16 testbit;
- /* 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;
/* set serial signal bits to reflect MISR */
@@ -4770,7 +4770,7 @@
info->serial_signals |= SerialSignal_DSR;
}
-/* 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 context.
*/
static void set_signals(SLMP_INFO *info)
