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Subject[PATCH 6/6] drivers/hid: Use DIV_ROUND_UP
From: Julia Lawall <julia@diku.dk>

The kernel.h macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /
(d)) but is perhaps more readable.

An extract of 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 n,d;
@@

(
- (n + d - 1) / d
+ DIV_ROUND_UP(n,d)
|
- (n + (d - 1)) / d
+ DIV_ROUND_UP(n,d)
)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP((n),d)
+ DIV_ROUND_UP(n,d)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP(n,(d))
+ DIV_ROUND_UP(n,d)
// </smpl>

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

---

diff -u -p a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
--- a/drivers/hid/usbhid/hid-core.c 2007-11-08 18:33:32.000000000 +0100
+++ b/drivers/hid/usbhid/hid-core.c 2008-02-13 20:51:00.000000000 +0100
@@ -278,7 +278,7 @@ static int hid_submit_ctrl(struct hid_de
usbhid->urbctrl->pipe = usb_rcvctrlpipe(hid_to_usb_dev(hid), 0);
maxpacket = usb_maxpacket(hid_to_usb_dev(hid), usbhid->urbctrl->pipe, 0);
if (maxpacket > 0) {
- padlen = (len + maxpacket - 1) / maxpacket;
+ padlen = DIV_ROUND_UP(len, maxpacket);
padlen *= maxpacket;
if (padlen > usbhid->bufsize)
padlen = usbhid->bufsize;

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