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Subject[PATCH v3 3/8] i2c: max2175: use 64-bit arithmetic instead of 32-bit
Add suffix LL to constant 2 in order to give the compiler complete
information about the proper arithmetic to use. Notice that this
constant is used in a context that expects an expression of type
s64 (64 bits, signed).

The expression 2 * (clock_rate - abs_nco_freq) is currently being
evaluated using 32-bit arithmetic.

Addresses-Coverity-ID: 1446589 ("Unintentional integer overflow")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
Changes in v2:
- Update subject and changelog to better reflect the proposed code changes.
- Add suffix LL to constant instead of casting a variable.

Changes in v3:
- Mention the specific Coverity report in the commit message.

drivers/media/i2c/max2175.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/i2c/max2175.c b/drivers/media/i2c/max2175.c
index 2f1966b..87cba15 100644
--- a/drivers/media/i2c/max2175.c
+++ b/drivers/media/i2c/max2175.c
@@ -643,7 +643,7 @@ static int max2175_set_nco_freq(struct max2175 *ctx, s32 nco_freq)
if (abs_nco_freq < clock_rate / 2) {
nco_val_desired = 2 * nco_freq;
} else {
- nco_val_desired = 2 * (clock_rate - abs_nco_freq);
+ nco_val_desired = 2LL * (clock_rate - abs_nco_freq);
if (nco_freq < 0)
nco_val_desired = -nco_val_desired;
}
--
2.7.4
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