Commit b6c2cb12 authored Mar 28, 2018 by Animesh Kishore Committed by raghavendra ambadas Aug 16, 2018

mdss: mdp: Fix fudge factor overflow check



Fudge adjustment is always 64 bit operation
irrespective of underlying architecture is
32/64 bit. Fix max value to compare overflow
against. Add warning if adjustments can't go
through without overflow.

Change-Id: I9c15ea8c1754c9ddb997546dc476bb6d45198524
Signed-off-by: Animesh Kishore <animeshk@codeaurora.org>

parent 994ee63f

drivers/video/msm/mdss/mdss_mdp_ctl.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -76,13 +76,15 @@ static inline u64 fudge_factor(u64 val, u32 numer, u32 denom)
		u64 result = val;

		if (val) {
		u64 temp = -1UL;
		u64 temp = U64_MAX;

		do_div(temp, val);
		if (temp > numer) {
		/* no overflow, so we can do the operation*/
		result = (val * (u64)numer);
		do_div(result, denom);
		} else {
		pr_warn("Overflow, skip fudge factor\n");
		}
		}
		return result;