clk: divider: Make generic for usage elsewhere

Some devices don't use mmio to interact with dividers. Split out the
logic from the register read/write parts so that we can reuse the
division logic elsewhere.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Tested-by: Kenneth Westfield <kwestfie@codeaurora.org>
Signed-off-by: Michael Turquette <mturquette@linaro.org>

2 files changed, 139 insertions, 84 deletions

diff --git a/drivers/clk/clk-divider.c b/drivers/clk/clk-divider.c
index c2bb9f679ec6..db7f8bce7467 100644
--- a/drivers/clk/clk-divider.c
+++ b/drivers/clk/clk-divider.c
@@ -30,7 +30,7 @@
 
 #define to_clk_divider(_hw) container_of(_hw, struct clk_divider, hw)
 
-#define div_mask(d)     ((1 << ((d)->width)) - 1)
+#define div_mask(width) ((1 << (width)) - 1)
 
 static unsigned int _get_table_maxdiv(const struct clk_div_table *table)
 {
@@ -54,15 +54,16 @@ static unsigned int _get_table_mindiv(const struct clk_div_table *table)
         return mindiv;
 }
 
-static unsigned int _get_maxdiv(struct clk_divider *divider)
+static unsigned int _get_maxdiv(const struct clk_div_table *table, u8 width,
+                                unsigned long flags)
 {
-        if (divider->flags & CLK_DIVIDER_ONE_BASED)
-                return div_mask(divider);
-        if (divider->flags & CLK_DIVIDER_POWER_OF_TWO)
-                return 1 << div_mask(divider);
-        if (divider->table)
-                return _get_table_maxdiv(divider->table);
-        return div_mask(divider) + 1;
+        if (flags & CLK_DIVIDER_ONE_BASED)
+                return div_mask(width);
+        if (flags & CLK_DIVIDER_POWER_OF_TWO)
+                return 1 << div_mask(width);
+        if (table)
+                return _get_table_maxdiv(table);
+        return div_mask(width) + 1;
 }
 
 static unsigned int _get_table_div(const struct clk_div_table *table,
@@ -76,14 +77,15 @@ static unsigned int _get_table_div(const struct clk_div_table *table,
         return 0;
 }
 
-static unsigned int _get_div(struct clk_divider *divider, unsigned int val)
+static unsigned int _get_div(const struct clk_div_table *table,
+                             unsigned int val, unsigned long flags)
 {
-        if (divider->flags & CLK_DIVIDER_ONE_BASED)
+        if (flags & CLK_DIVIDER_ONE_BASED)
                 return val;
-        if (divider->flags & CLK_DIVIDER_POWER_OF_TWO)
+        if (flags & CLK_DIVIDER_POWER_OF_TWO)
                 return 1 << val;
-        if (divider->table)
-                return _get_table_div(divider->table, val);
+        if (table)
+                return _get_table_div(table, val);
         return val + 1;
 }
 
@@ -98,29 +100,28 @@ static unsigned int _get_table_val(const struct clk_div_table *table,
         return 0;
 }
 
-static unsigned int _get_val(struct clk_divider *divider, unsigned int div)
+static unsigned int _get_val(const struct clk_div_table *table,
+                             unsigned int div, unsigned long flags)
 {
-        if (divider->flags & CLK_DIVIDER_ONE_BASED)
+        if (flags & CLK_DIVIDER_ONE_BASED)
                 return div;
-        if (divider->flags & CLK_DIVIDER_POWER_OF_TWO)
+        if (flags & CLK_DIVIDER_POWER_OF_TWO)
                 return __ffs(div);
-        if (divider->table)
-                return  _get_table_val(divider->table, div);
+        if (table)
+                return  _get_table_val(table, div);
         return div - 1;
 }
 
-static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
-                unsigned long parent_rate)
+unsigned long divider_recalc_rate(struct clk_hw *hw, unsigned long parent_rate,
+                                  unsigned int val,
+                                  const struct clk_div_table *table,
+                                  unsigned long flags)
 {
-        struct clk_divider *divider = to_clk_divider(hw);
-        unsigned int div, val;
+        unsigned int div;
 
-        val = clk_readl(divider->reg) >> divider->shift;
-        val &= div_mask(divider);
-
-        div = _get_div(divider, val);
+        div = _get_div(table, val, flags);
         if (!div) {
-                WARN(!(divider->flags & CLK_DIVIDER_ALLOW_ZERO),
+                WARN(!(flags & CLK_DIVIDER_ALLOW_ZERO),
                         "%s: Zero divisor and CLK_DIVIDER_ALLOW_ZERO not set\n",
                         __clk_get_name(hw->clk));
                 return parent_rate;
@@ -128,6 +129,20 @@ static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
 
         return DIV_ROUND_UP(parent_rate, div);
 }
+EXPORT_SYMBOL_GPL(divider_recalc_rate);
+
+static unsigned long clk_divider_recalc_rate(struct clk_hw *hw,
+                unsigned long parent_rate)
+{
+        struct clk_divider *divider = to_clk_divider(hw);
+        unsigned int val;
+
+        val = clk_readl(divider->reg) >> divider->shift;
+        val &= div_mask(divider->width);
+
+        return divider_recalc_rate(hw, parent_rate, val, divider->table,
+                                   divider->flags);
+}
 
 /*
  * The reverse of DIV_ROUND_UP: The maximum number which
@@ -146,12 +161,13 @@ static bool _is_valid_table_div(const struct clk_div_table *table,
         return false;
 }
 
-static bool _is_valid_div(struct clk_divider *divider, unsigned int div)
+static bool _is_valid_div(const struct clk_div_table *table, unsigned int div,
+                          unsigned long flags)
 {
-        if (divider->flags & CLK_DIVIDER_POWER_OF_TWO)
+        if (flags & CLK_DIVIDER_POWER_OF_TWO)
                 return is_power_of_2(div);
-        if (divider->table)
-                return _is_valid_table_div(divider->table, div);
+        if (table)
+                return _is_valid_table_div(table, div);
         return true;
 }
 
@@ -191,71 +207,76 @@ static int _round_down_table(const struct clk_div_table *table, int div)
         return down;
 }
 
-static int _div_round_up(struct clk_divider *divider,
-                unsigned long parent_rate, unsigned long rate)
+static int _div_round_up(const struct clk_div_table *table,
+                         unsigned long parent_rate, unsigned long rate,
+                         unsigned long flags)
 {
         int div = DIV_ROUND_UP(parent_rate, rate);
 
-        if (divider->flags & CLK_DIVIDER_POWER_OF_TWO)
+        if (flags & CLK_DIVIDER_POWER_OF_TWO)
                 div = __roundup_pow_of_two(div);
-        if (divider->table)
-                div = _round_up_table(divider->table, div);
+        if (table)
+                div = _round_up_table(table, div);
 
         return div;
 }
 
-static int _div_round_closest(struct clk_divider *divider,
-                unsigned long parent_rate, unsigned long rate)
+static int _div_round_closest(const struct clk_div_table *table,
+                              unsigned long parent_rate, unsigned long rate,
+                              unsigned long flags)
 {
         int up, down, div;
 
         up = down = div = DIV_ROUND_CLOSEST(parent_rate, rate);
 
-        if (divider->flags & CLK_DIVIDER_POWER_OF_TWO) {
+        if (flags & CLK_DIVIDER_POWER_OF_TWO) {
                 up = __roundup_pow_of_two(div);