[PATCH v2 2/7] staging: most: Using macro DIV_ROUND_UP

From: simran singhal
Date: Wed Feb 22 2017 - 04:10:32 EST


The macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /(d)).
It clarifies the divisor calculations. This occurence was detected using
the coccinelle script:

@@
expression e1;
expression e2;
@@
(
- ((e1) + e2 - 1) / (e2)
+ DIV_ROUND_UP(e1,e2)
|
- ((e1) + (e2 - 1)) / (e2)
+ DIV_ROUND_UP(e1,e2)
)

Signed-off-by: simran singhal <singhalsimran0@xxxxxxxxx>
---

v2:
-Included kernel.h as DIV_ROUND_UP is defined in it,
before it was giving compilation error.

drivers/staging/most/hdm-dim2/dim2_hal.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/most/hdm-dim2/dim2_hal.c b/drivers/staging/most/hdm-dim2/dim2_hal.c
index 0b9816c..d604ec09 100644
--- a/drivers/staging/most/hdm-dim2/dim2_hal.c
+++ b/drivers/staging/most/hdm-dim2/dim2_hal.c
@@ -18,6 +18,7 @@
#include "dim2_errors.h"
#include "dim2_reg.h"
#include <linux/stddef.h>
+#include <linux/kernel.h>

/*
* Size factor for isochronous DBR buffer.
@@ -49,7 +50,7 @@
#define DBR_SIZE (16 * 1024) /* specified by IP */
#define DBR_BLOCK_SIZE (DBR_SIZE / 32 / DBR_MAP_SIZE)

-#define ROUND_UP_TO(x, d) (((x) + (d) - 1) / (d) * (d))
+#define ROUND_UP_TO(x, d) (DIV_ROUND_UP(x, (d)) * (d))

/* -------------------------------------------------------------------------- */
/* generic helper functions and macros */
@@ -117,7 +118,7 @@ static int alloc_dbr(u16 size)
return DBR_SIZE; /* out of memory */

for (i = 0; i < DBR_MAP_SIZE; i++) {
- u32 const blocks = (size + DBR_BLOCK_SIZE - 1) / DBR_BLOCK_SIZE;
+ u32 const blocks = DIV_ROUND_UP(size, DBR_BLOCK_SIZE);
u32 mask = ~((~(u32)0) << blocks);

do {
@@ -137,7 +138,7 @@ static int alloc_dbr(u16 size)
static void free_dbr(int offs, int size)
{
int block_idx = offs / DBR_BLOCK_SIZE;
- u32 const blocks = (size + DBR_BLOCK_SIZE - 1) / DBR_BLOCK_SIZE;
+ u32 const blocks = DIV_ROUND_UP(size, DBR_BLOCK_SIZE);
u32 mask = ~((~(u32)0) << blocks);

mask <<= block_idx % 32;
--
2.7.4