Merge tag 'fbdev-updates-for-3.5' of git://github.com/schandinat/linux-2.6

[~andy/linux] / drivers / clk / clk-gate.c

diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c
index b5902e2ef2fd72f73ce44166222d6d3ebb76a5c6..578465e04be6b900c37009a7bfe3feb3c7506728 100644 (file)
--- a/drivers/clk/clk-gate.c
+++ b/drivers/clk/clk-gate.c
@@ -28,32 +28,38 @@
 
 #define to_clk_gate(_hw) container_of(_hw, struct clk_gate, hw)
 
-static void clk_gate_set_bit(struct clk_gate *gate)
+/*
+ * It works on following logic:
+ *
+ * For enabling clock, enable = 1
+ *     set2dis = 1     -> clear bit    -> set = 0
+ *     set2dis = 0     -> set bit      -> set = 1
+ *
+ * For disabling clock, enable = 0
+ *     set2dis = 1     -> set bit      -> set = 1
+ *     set2dis = 0     -> clear bit    -> set = 0
+ *
+ * So, result is always: enable xor set2dis.
+ */
+static void clk_gate_endisable(struct clk_hw *hw, int enable)
 {
-       u32 reg;
+       struct clk_gate *gate = to_clk_gate(hw);
+       int set = gate->flags & CLK_GATE_SET_TO_DISABLE ? 1 : 0;
        unsigned long flags = 0;
+       u32 reg;
+
+       set ^= enable;
 
        if (gate->lock)
                spin_lock_irqsave(gate->lock, flags);
 
        reg = readl(gate->reg);
-       reg |= BIT(gate->bit_idx);
-       writel(reg, gate->reg);
-
-       if (gate->lock)
-               spin_unlock_irqrestore(gate->lock, flags);
-}
-
-static void clk_gate_clear_bit(struct clk_gate *gate)
-{
-       u32 reg;
-       unsigned long flags = 0;
 
-       if (gate->lock)
-               spin_lock_irqsave(gate->lock, flags);
+       if (set)
+               reg |= BIT(gate->bit_idx);
+       else
+               reg &= ~BIT(gate->bit_idx);
 
-       reg = readl(gate->reg);
-       reg &= ~BIT(gate->bit_idx);
        writel(reg, gate->reg);
 
        if (gate->lock)
@@ -62,27 +68,15 @@ static void clk_gate_clear_bit(struct clk_gate *gate)
 
 static int clk_gate_enable(struct clk_hw *hw)
 {
-       struct clk_gate *gate = to_clk_gate(hw);
-
-       if (gate->flags & CLK_GATE_SET_TO_DISABLE)
-               clk_gate_clear_bit(gate);
-       else
-               clk_gate_set_bit(gate);
+       clk_gate_endisable(hw, 1);
 
        return 0;
 }
-EXPORT_SYMBOL_GPL(clk_gate_enable);
 
 static void clk_gate_disable(struct clk_hw *hw)
 {
-       struct clk_gate *gate = to_clk_gate(hw);
-
-       if (gate->flags & CLK_GATE_SET_TO_DISABLE)
-               clk_gate_set_bit(gate);
-       else
-               clk_gate_clear_bit(gate);
+       clk_gate_endisable(hw, 0);
 }
-EXPORT_SYMBOL_GPL(clk_gate_disable);
 
 static int clk_gate_is_enabled(struct clk_hw *hw)
 {
@@ -99,15 +93,25 @@ static int clk_gate_is_enabled(struct clk_hw *hw)
 
        return reg ? 1 : 0;
 }
-EXPORT_SYMBOL_GPL(clk_gate_is_enabled);
 
-struct clk_ops clk_gate_ops = {
+const struct clk_ops clk_gate_ops = {
        .enable = clk_gate_enable,
        .disable = clk_gate_disable,
        .is_enabled = clk_gate_is_enabled,
 };
 EXPORT_SYMBOL_GPL(clk_gate_ops);
 
+/**
+ * clk_register_gate - register a gate clock with the clock framework
+ * @dev: device that is registering this clock
+ * @name: name of this clock
+ * @parent_name: name of this clock's parent
+ * @flags: framework-specific flags for this clock
+ * @reg: register address to control gating of this clock
+ * @bit_idx: which bit in the register controls gating of this clock
+ * @clk_gate_flags: gate-specific flags for this clock
+ * @lock: shared register lock for this clock
+ */
 struct clk *clk_register_gate(struct device *dev, const char *name,
                const char *parent_name, unsigned long flags,
                void __iomem *reg, u8 bit_idx,
@@ -115,36 +119,32 @@ struct clk *clk_register_gate(struct device *dev, const char *name,
 {
        struct clk_gate *gate;
        struct clk *clk;
+       struct clk_init_data init;
 
+       /* allocate the gate */
        gate = kzalloc(sizeof(struct clk_gate), GFP_KERNEL);
-
        if (!gate) {
                pr_err("%s: could not allocate gated clk\n", __func__);
-               return NULL;
+               return ERR_PTR(-ENOMEM);
        }
 
+       init.name = name;
+       init.ops = &clk_gate_ops;
+       init.flags = flags;
+       init.parent_names = (parent_name ? &parent_name: NULL);
+       init.num_parents = (parent_name ? 1 : 0);
+
        /* struct clk_gate assignments */
        gate->reg = reg;
        gate->bit_idx = bit_idx;
        gate->flags = clk_gate_flags;
        gate->lock = lock;
+       gate->hw.init = &init;
 
-       if (parent_name) {
-               gate->parent[0] = kstrdup(parent_name, GFP_KERNEL);
-               if (!gate->parent[0])
-                       goto out;
-       }
+       clk = clk_register(dev, &gate->hw);
+
+       if (IS_ERR(clk))
+               kfree(gate);
 
-       clk = clk_register(dev, name,
-                       &clk_gate_ops, &gate->hw,
-                       gate->parent,
-                       (parent_name ? 1 : 0),
-                       flags);
-       if (clk)
-               return clk;
-out:
-       kfree(gate->parent[0]);
-       kfree(gate);
-
-       return NULL;
+       return clk;
 }