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clk: sunxi-ng: fix recalc_rate formula of NKMP clocks

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In commit e66f81bbd7 ("clk: sunxi-ng: Implement factors offsets"), the
final formula of NKMP clocks' recalc_rate is refactored; however, the
refactored formula broke the calculation due to some C language operand
priority problem -- the priority of operand >> is lower than * and /,
makes the formula being parsed as "(parent_rate * n * k) >> (p / m)", but
it should be "(parent_rate * n * k >> p) / m".

Add the pair of parentheses to fix up this issue. This pair of
parentheses used to exist in the old formula.

Fixes: e66f81bbd7 ("clk: sunxi-ng: Implement factors offsets")
Signed-off-by: Icenowy Zheng <icenowy@aosc.xyz>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
This commit is contained in:
Icenowy Zheng 2017-03-18 04:19:43 +08:00 committed by Maxime Ripard
parent fe686babf4
commit b467e08a15
1 changed files with 1 additions and 1 deletions
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2
drivers/clk/sunxi-ng/ccu_nkmp.c
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@ -107,7 +107,7 @@ static unsigned long ccu_nkmp_recalc_rate(struct clk_hw *hw,
p = reg >> nkmp->p.shift;
p &= (1 << nkmp->p.width) - 1;
return parent_rate * n * k >> p / m;
return (parent_rate * n * k >> p) / m;
}
static long ccu_nkmp_round_rate(struct clk_hw *hw, unsigned long rate,