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Subject[PATCH v3 1/3] clk: fractional-divider: fix sparse warnings
Date
Sparse complains about possible imbalance in locking.

drivers/clk/clk-fractional-divider.c:37:9: warning: context imbalance in 'clk_fd_recalc_rate' - different lock contexts for basic block
drivers/clk/clk-fractional-divider.c:61:12: warning: context imbalance in 'clk_fd_set_rate' - different lock contexts for basic block

Let's rewrite code to fix this and make it more straight.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
drivers/clk/clk-fractional-divider.c | 44 +++++++++++++++++++++---------------
1 file changed, 26 insertions(+), 18 deletions(-)

diff --git a/drivers/clk/clk-fractional-divider.c b/drivers/clk/clk-fractional-divider.c
index 6aa72d9..786aa482 100644
--- a/drivers/clk/clk-fractional-divider.c
+++ b/drivers/clk/clk-fractional-divider.c
@@ -21,17 +21,18 @@ static unsigned long clk_fd_recalc_rate(struct clk_hw *hw,
unsigned long parent_rate)
{
struct clk_fractional_divider *fd = to_clk_fd(hw);
- unsigned long flags = 0;
- u32 val, m, n;
+ unsigned long flags;
+ unsigned long m, n;
+ u32 val;
u64 ret;

- if (fd->lock)
+ if (fd->lock) {
spin_lock_irqsave(fd->lock, flags);
-
- val = clk_readl(fd->reg);
-
- if (fd->lock)
+ val = clk_readl(fd->reg);
spin_unlock_irqrestore(fd->lock, flags);
+ } else {
+ val = clk_readl(fd->reg);
+ }

m = (val & fd->mmask) >> fd->mshift;
n = (val & fd->nmask) >> fd->nshift;
@@ -65,29 +66,36 @@ static long clk_fd_round_rate(struct clk_hw *hw, unsigned long rate,
return rate;
}

+static void clk_fd_update(struct clk_fractional_divider *fd,
+ unsigned long m, unsigned long n)
+{
+ u32 val;
+
+ val = clk_readl(fd->reg);
+ val &= ~(fd->mmask | fd->nmask);
+ val |= (m << fd->mshift) | (n << fd->nshift);
+ clk_writel(val, fd->reg);
+}
+
static int clk_fd_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long parent_rate)
{
struct clk_fractional_divider *fd = to_clk_fd(hw);
- unsigned long flags = 0;
+ unsigned long flags;
unsigned long div;
- unsigned n, m;
- u32 val;
+ unsigned long m, n;

div = gcd(parent_rate, rate);
m = rate / div;
n = parent_rate / div;

- if (fd->lock)
+ if (fd->lock) {
spin_lock_irqsave(fd->lock, flags);
-
- val = clk_readl(fd->reg);
- val &= ~(fd->mmask | fd->nmask);
- val |= (m << fd->mshift) | (n << fd->nshift);
- clk_writel(val, fd->reg);
-
- if (fd->lock)
+ clk_fd_update(fd, m, n);
spin_unlock_irqrestore(fd->lock, flags);
+ } else {
+ clk_fd_update(fd, m, n);
+ }

return 0;
}
--
2.1.4


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