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Diffstat (limited to 'drivers/clk/clk-divider.c')
-rw-r--r--drivers/clk/clk-divider.c47
1 files changed, 41 insertions, 6 deletions
diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
index 5543b7df8e1..3fbee454022 100644
--- a/drivers/clk/clk-divider.c
+++ b/drivers/clk/clk-divider.c
@@ -24,7 +24,7 @@
* Traits of this clock:
* prepare - clk_prepare only ensures that parents are prepared
* enable - clk_enable only ensures that parents are enabled
- * rate - rate is adjustable. clk->rate = parent->rate / divisor
+ * rate - rate is adjustable. clk->rate = DIV_ROUND_UP(parent->rate / divisor)
* parent - fixed parent. No clk_set_parent support
*/
@@ -115,7 +115,7 @@ static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
return parent_rate;
}
- return parent_rate / div;
+ return DIV_ROUND_UP(parent_rate, div);
}
/*
@@ -144,6 +144,37 @@ static bool _is_valid_div(struct clk_divider *divider, unsigned int div)
return true;
}
+static int _round_up_table(const struct clk_div_table *table, int div)
+{
+ const struct clk_div_table *clkt;
+ int up = INT_MAX;
+
+ for (clkt = table; clkt->div; clkt++) {
+ if (clkt->div == div)
+ return clkt->div;
+ else if (clkt->div < div)
+ continue;
+
+ if ((clkt->div - div) < (up - div))
+ up = clkt->div;
+ }
+
+ return up;
+}
+
+static int _div_round_up(struct clk_divider *divider,
+ unsigned long parent_rate, unsigned long rate)
+{
+ int div = DIV_ROUND_UP(parent_rate, rate);
+
+ if (divider->flags & CLK_DIVIDER_POWER_OF_TWO)
+ div = __roundup_pow_of_two(div);
+ if (divider->table)
+ div = _round_up_table(divider->table, div);
+
+ return div;
+}
+
static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate,
unsigned long *best_parent_rate)
{
@@ -159,7 +190,7 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate,
if (!(__clk_get_flags(hw->clk) & CLK_SET_RATE_PARENT)) {
parent_rate = *best_parent_rate;
- bestdiv = DIV_ROUND_UP(parent_rate, rate);
+ bestdiv = _div_round_up(divider, parent_rate, rate);
bestdiv = bestdiv == 0 ? 1 : bestdiv;
bestdiv = bestdiv > maxdiv ? maxdiv : bestdiv;
return bestdiv;
@@ -185,7 +216,7 @@ static int clk_divider_bestdiv(struct clk_hw *hw, unsigned long rate,
}
parent_rate = __clk_round_rate(__clk_get_parent(hw->clk),
MULT_ROUND_UP(rate, i));
- now = parent_rate / i;
+ now = DIV_ROUND_UP(parent_rate, i);
if (now <= rate && now > best) {
bestdiv = i;
best = now;
@@ -207,7 +238,7 @@ static long clk_divider_round_rate(struct clk_hw *hw, unsigned long rate,
int div;
div = clk_divider_bestdiv(hw, rate, prate);
- return *prate / div;
+ return DIV_ROUND_UP(*prate, div);
}
static int clk_divider_set_rate(struct clk_hw *hw, unsigned long rate,
@@ -218,7 +249,11 @@ static int clk_divider_set_rate(struct clk_hw *hw, unsigned long rate,
unsigned long flags = 0;
u32 val;
- div = parent_rate / rate;
+ div = DIV_ROUND_UP(parent_rate, rate);
+
+ if (!_is_valid_div(divider, div))
+ return -EINVAL;
+
value = _get_val(divider, div);
if (value > div_mask(divider))