clk: gate: Add support for specifying parents via DT/pointers

After commit fc0c209c ("clk: Allow parents to be specified without
string names") we can use DT or direct clk_hw pointers to specify
parents. Create a generic function that shouldn't be used very often to
encode the multitude of ways of registering a gate clk with different
parent information. Then add a bunch of wrapper macros that only pass
down what needs to be passed down to the generic function to support
this with less arguments.

Cc: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lkml.kernel.org/r/20190830150923.259497-12-sboyd@kernel.org

drivers/clk/clk-gate.c

@@ -123,26 +123,18 @@ const struct clk_ops clk_gate_ops = {
 };
 EXPORT_SYMBOL_GPL(clk_gate_ops);
 
-/**
- * clk_hw_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_hw *clk_hw_register_gate(struct device *dev, const char *name,
-		const char *parent_name, unsigned long flags,
+struct clk_hw *__clk_hw_register_gate(struct device *dev,
+		struct device_node *np, const char *name,
+		const char *parent_name, const struct clk_hw *parent_hw,
+		const struct clk_parent_data *parent_data,
+		unsigned long flags,
 		void __iomem *reg, u8 bit_idx,
 		u8 clk_gate_flags, spinlock_t *lock)
 {
 	struct clk_gate *gate;
 	struct clk_hw *hw;
 	struct clk_init_data init = {};
-	int ret;
+	int ret = -EINVAL;
 
 	if (clk_gate_flags & CLK_GATE_HIWORD_MASK) {
 		if (bit_idx > 15) {
@@ -160,7 +152,12 @@ struct clk_hw *clk_hw_register_gate(struct device *dev, const char *name,
 	init.ops = &clk_gate_ops;
 	init.flags = flags;
 	init.parent_names = parent_name ? &parent_name : NULL;
-	init.num_parents = parent_name ? 1 : 0;
+	init.parent_hws = parent_hw ? &parent_hw : NULL;
+	init.parent_data = parent_data;
+	if (parent_name || parent_hw || parent_data)
+		init.num_parents = 1;
+	else
+		init.num_parents = 0;
 
 	/* struct clk_gate assignments */
 	gate->reg = reg;
@@ -170,15 +167,19 @@ struct clk_hw *clk_hw_register_gate(struct device *dev, const char *name,
 	gate->hw.init = &init;
 
 	hw = &gate->hw;
-	ret = clk_hw_register(dev, hw);
+	if (dev || !np)
+		ret = clk_hw_register(dev, hw);
+	else if (np)
+		ret = of_clk_hw_register(np, hw);
 	if (ret) {
 		kfree(gate);
 		hw = ERR_PTR(ret);
 	}
 
 	return hw;
+
 }
-EXPORT_SYMBOL_GPL(clk_hw_register_gate);
+EXPORT_SYMBOL_GPL(__clk_hw_register_gate);
 
 struct clk *clk_register_gate(struct device *dev, const char *name,
 		const char *parent_name, unsigned long flags,

include/linux/clk-provider.h

@@ -476,14 +476,67 @@ struct clk_gate {
 #define CLK_GATE_BIG_ENDIAN		BIT(2)
 
 extern const struct clk_ops clk_gate_ops;
-struct clk *clk_register_gate(struct device *dev, const char *name,
-		const char *parent_name, unsigned long flags,
+struct clk_hw *__clk_hw_register_gate(struct device *dev,
+		struct device_node *np, const char *name,
+		const char *parent_name, const struct clk_hw *parent_hw,
+		const struct clk_parent_data *parent_data,
+		unsigned long flags,
 		void __iomem *reg, u8 bit_idx,
 		u8 clk_gate_flags, spinlock_t *lock);
-struct clk_hw *clk_hw_register_gate(struct device *dev, const char *name,
+struct clk *clk_register_gate(struct device *dev, const char *name,
 		const char *parent_name, unsigned long flags,
 		void __iomem *reg, u8 bit_idx,
 		u8 clk_gate_flags, spinlock_t *lock);
+/**
+ * clk_hw_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
+ */
+#define clk_hw_register_gate(dev, name, parent_name, flags, reg, bit_idx,     \
+			     clk_gate_flags, lock)			      \
+	__clk_hw_register_gate((dev), NULL, (name), (parent_name), NULL,      \
+			       NULL, (flags), (reg), (bit_idx),		      \
+			       (clk_gate_flags), (lock))
+/**
+ * clk_hw_register_gate_parent_hw - register a gate clock with the clock
+ * framework
+ * @dev: device that is registering this clock
+ * @name: name of this clock
+ * @parent_hw: pointer to parent clk
+ * @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
+ */
+#define clk_hw_register_gate_parent_hw(dev, name, parent_name, flags, reg,    \
+				       bit_idx, clk_gate_flags, lock)	      \
+	__clk_hw_register_gate((dev), NULL, (name), (parent_name), NULL,      \
+			       NULL, (flags), (reg), (bit_idx),		      \
+			       (clk_gate_flags), (lock))
+/**
+ * clk_hw_register_gate_parent_data - register a gate clock with the clock
+ * framework
+ * @dev: device that is registering this clock
+ * @name: name of this clock
+ * @parent_data: parent clk data
+ * @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
+ */
+#define clk_hw_register_gate_parent_data(dev, name, parent_name, flags, reg,  \
+				       bit_idx, clk_gate_flags, lock)	      \
+	__clk_hw_register_gate((dev), NULL, (name), (parent_name), NULL,      \
+			       NULL, (flags), (reg), (bit_idx),		      \
+			       (clk_gate_flags), (lock))
 void clk_unregister_gate(struct clk *clk);
 void clk_hw_unregister_gate(struct clk_hw *hw);
 int clk_gate_is_enabled(struct clk_hw *hw);