[PATCH v2] mfd: tps65911-comparator: Fix an off by one bug

Dan Carpenter
2018-04-20T09:09:10Z

The COMP1 and COMP2 elements are in 0 and 1 respectively so this code is
accessing the wrong elements and one space beyond the end of the array.
We should be using "id - 1" instead.

The "id" variable is never COMP (0) so that code can be removed.

Fixes: 6851ad3ab346 ("TPS65911: Comparator: Add comparator driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
---
v2: we can fix the bug and save memory.

diff --git a/drivers/mfd/tps65911-comparator.c b/drivers/mfd/tps65911-comparator.c
index c0789f81a1c5..887409c3938d 100644
--- a/drivers/mfd/tps65911-comparator.c
+++ b/drivers/mfd/tps65911-comparator.c
@@ -22,7 +22,6 @@
#include <linux/gpio.h>
#include <linux/mfd/tps65910.h>

-#define COMP 0
#define COMP1 1
#define COMP2 2

@@ -58,14 +57,11 @@ static struct comparator tps_comparators[] = {

static int comp_threshold_set(struct tps65910 *tps65910, int id, int voltage)
{
- struct comparator tps_comp = tps_comparators[id];
+ struct comparator tps_comp = tps_comparators[id - 1];
int curr_voltage = 0;
int ret;
u8 index = 0, val;

- if (id = COMP)
- return 0;
-
while (curr_voltage < tps_comp.uV_max) {
curr_voltage = tps_comp.vsel_table[index];
if (curr_voltage >= voltage)
@@ -85,13 +81,10 @@ static int comp_threshold_set(struct tps65910 *tps65910, int id, int voltage)

static int comp_threshold_get(struct tps65910 *tps65910, int id)
{
- struct comparator tps_comp = tps_comparators[id];
+ struct comparator tps_comp = tps_comparators[id - 1];
int ret;
u8 val;

- if (id = COMP)
- return 0;
-
ret = tps65910->read(tps65910, tps_comp.reg, 1, &val);
if (ret < 0)
return ret;