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Subject[PATCH 14/15] drivers/char/specialix.c: Use DIV_ROUND_CLOSEST
From: Julia Lawall <julia@diku.dk>

The kernel.h macro DIV_ROUND_CLOSEST performs the computation (x + d/2)/d
but is perhaps more readable.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@haskernel@
@@

#include <linux/kernel.h>

@depends on haskernel@
expression x,__divisor;
@@

- (((x) + ((__divisor) / 2)) / (__divisor))
+ DIV_ROUND_CLOSEST(x,__divisor)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>

---
drivers/char/specialix.c | 13 ++++++-------
1 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/char/specialix.c b/drivers/char/specialix.c
index 268e17f..1d295fc 100644
--- a/drivers/char/specialix.c
+++ b/drivers/char/specialix.c
@@ -1026,8 +1026,8 @@ static void sx_change_speed(struct specialix_board *bp,
"This is an untested option, please be careful.\n",
port_No(port), tmp);
else
- tmp = (((SX_OSCFREQ + baud/2) / baud + CD186x_TPC/2) /
- CD186x_TPC);
+ tmp = DIV_ROUND_CLOSEST(DIV_ROUND_CLOSEST(SX_OSCFREQ, baud),
+ CD186x_TPC);

if (tmp < 0x10 && time_before(again, jiffies)) {
again = jiffies + HZ * 60;
@@ -1050,17 +1050,16 @@ static void sx_change_speed(struct specialix_board *bp,
sx_out(bp, CD186x_TBPRL, tmp & 0xff);
spin_unlock_irqrestore(&bp->lock, flags);
if (port->custom_divisor)
- baud = (SX_OSCFREQ + port->custom_divisor/2) /
- port->custom_divisor;
+ baud = DIV_ROUND_CLOSEST(SX_OSCFREQ, port->custom_divisor);
baud = (baud + 5) / 10; /* Estimated CPS */

/* Two timer ticks seems enough to wakeup something like SLIP driver */
- tmp = ((baud + HZ/2) / HZ) * 2 - CD186x_NFIFO;
+ tmp = DIV_ROUND_CLOSEST(baud, HZ) * 2 - CD186x_NFIFO;
port->wakeup_chars = (tmp < 0) ? 0 : ((tmp >= SERIAL_XMIT_SIZE) ?
SERIAL_XMIT_SIZE - 1 : tmp);

/* Receiver timeout will be transmission time for 1.5 chars */
- tmp = (SPECIALIX_TPS + SPECIALIX_TPS/2 + baud/2) / baud;
+ tmp = DIV_ROUND_CLOSEST(SPECIALIX_TPS + SPECIALIX_TPS / 2, baud);
tmp = (tmp > 0xff) ? 0xff : tmp;
spin_lock_irqsave(&bp->lock, flags);
sx_out(bp, CD186x_RTPR, tmp);
@@ -1913,7 +1912,7 @@ static int sx_get_serial_info(struct specialix_port *port,
tmp.port = bp->base;
tmp.irq = bp->irq;
tmp.flags = port->port.flags;
- tmp.baud_base = (SX_OSCFREQ + CD186x_TPC/2) / CD186x_TPC;
+ tmp.baud_base = DIV_ROUND_CLOSEST(SX_OSCFREQ, CD186x_TPC);
tmp.close_delay = port->port.close_delay * HZ/100;
tmp.closing_wait = port->port.closing_wait * HZ/100;
tmp.custom_divisor = port->custom_divisor;

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