clk: mmp: add spin lock for clk-frac
The register used by clk-frac may be shared with
other clocks.
So it needs to use spin lock to protect the register
access.
Signed-off-by: Chao Xie <chao.xie@marvell.com>
Acked-by: Haojian Zhuang <haojian.zhuang@gmail.com>
Signed-off-by: Michael Turquette <mturquette@linaro.org>
diff --git a/drivers/clk/mmp/clk-frac.c b/drivers/clk/mmp/clk-frac.c
index 3fbc9ca..e29d006 100644
--- a/drivers/clk/mmp/clk-frac.c
+++ b/drivers/clk/mmp/clk-frac.c
@@ -29,6 +29,7 @@
struct mmp_clk_factor_masks *masks;
struct mmp_clk_factor_tbl *ftbl;
unsigned int ftbl_cnt;
+ spinlock_t *lock;
};
static long clk_factor_round_rate(struct clk_hw *hw, unsigned long drate,
@@ -86,6 +87,7 @@
int i;
unsigned long val;
unsigned long prev_rate, rate = 0;
+ unsigned long flags = 0;
for (i = 0; i < factor->ftbl_cnt; i++) {
prev_rate = rate;
@@ -97,6 +99,9 @@
if (i > 0)
i--;
+ if (factor->lock)
+ spin_lock_irqsave(factor->lock, flags);
+
val = readl_relaxed(factor->base);
val &= ~(masks->num_mask << masks->num_shift);
@@ -107,6 +112,9 @@
writel_relaxed(val, factor->base);
+ if (factor->lock)
+ spin_unlock_irqrestore(factor->lock, flags);
+
return 0;
}
@@ -120,7 +128,7 @@
unsigned long flags, void __iomem *base,
struct mmp_clk_factor_masks *masks,
struct mmp_clk_factor_tbl *ftbl,
- unsigned int ftbl_cnt)
+ unsigned int ftbl_cnt, spinlock_t *lock)
{
struct mmp_clk_factor *factor;
struct clk_init_data init;
@@ -143,6 +151,7 @@
factor->ftbl = ftbl;
factor->ftbl_cnt = ftbl_cnt;
factor->hw.init = &init;
+ factor->lock = lock;
init.name = name;
init.ops = &clk_factor_ops;