diff options
Diffstat (limited to 'drivers/clk/clk-gate.c')
| -rw-r--r-- | drivers/clk/clk-gate.c | 104 |
1 files changed, 52 insertions, 52 deletions
diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c index b5902e2ef2fd..578465e04be6 100644 --- 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; } |