[PATCH v2 4/4] clk: gate: Add DT binding

[David Yang <mmyangfl@gmail.com>]

Add DT binding for gate clock as "gate-clock".

Signed-off-by: David Yang <mmyangfl@gmail.com>
---
 drivers/clk/clk-gate.c | 81 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 81 insertions(+)

diff --git a/drivers/clk/clk-gate.c b/drivers/clk/clk-gate.c
index 64283807600b..a70df4a2a9a7 100644
--- a/drivers/clk/clk-gate.c
+++ b/drivers/clk/clk-gate.c
@@ -12,8 +12,11 @@
 #include <linux/slab.h>
 #include <linux/io.h>
 #include <linux/err.h>
+#include <linux/platform_device.h>
 #include <linux/string.h>
 
+#include "clk-of.h"
+
 /**
  * DOC: basic gatable clock which can gate and ungate it's ouput
  *
@@ -257,3 +260,81 @@ struct clk_hw *__devm_clk_hw_register_gate(struct device *dev,
 	return hw;
 }
 EXPORT_SYMBOL_GPL(__devm_clk_hw_register_gate);
+
+#if IS_ENABLED(CONFIG_OF)
+static const struct of_clk_flag of_clk_gate_flags[] = {
+	{ "set-to-disable", CLK_GATE_SET_TO_DISABLE },
+	{ "hiword-mask", CLK_GATE_HIWORD_MASK },
+	{ "big-endian", CLK_GATE_BIG_ENDIAN },
+	{ }
+};
+
+static int of_clk_gate_setup(struct device_node *np)
+{
+	struct of_clk_ctrl *ctrl = np->parent->data;
+	const char *name;
+	void __iomem *reg;
+	u32 bit_idx;
+
+	const char *property;
+	struct clk_hw *hw;
+	int ret;
+
+	reg = of_clk_get_reg(np);
+	if (!reg)
+		return -ENOMEM;
+	name = of_clk_get_name(np);
+	if (!name)
+		return -EINVAL;
+
+	property = "bits";
+	if (of_property_read_u32(np, property, &bit_idx))
+		goto err_property;
+
+	hw = __clk_hw_register_gate(NULL, np, name,
+				    of_clk_get_parent_name(np, 0),
+				    NULL, NULL, of_clk_get_flags(np, NULL),
+				    reg, bit_idx,
+				    of_clk_get_flags(np, of_clk_gate_flags),
+				    &ctrl->lock);
+	if (IS_ERR(hw))
+		return PTR_ERR(hw);
+
+	ret = of_clk_add_hw_provider(np, of_clk_hw_simple_get, hw);
+	if (ret)
+		goto err_register;
+
+	np->data = hw;
+	return 0;
+
+err_register:
+	clk_hw_unregister(hw);
+	return ret;
+
+err_property:
+	pr_err("%s: clock %s missing required property \"%s\"\n",
+	       __func__, name, property);
+	return -EINVAL;
+}
+
+static void __init of_clk_gate_init(struct device_node *np)
+{
+	of_clk_gate_setup(np);
+}
+CLK_OF_DECLARE(of_clk_gate, "gate-clock", of_clk_gate_init);
+
+static const struct of_device_id of_clk_gate_ids[] = {
+	{ .compatible = "gate-clock", .data = of_clk_gate_setup },
+	{ }
+};
+
+static struct platform_driver of_clk_gate_driver = {
+	.driver = {
+		.name = "clk_gate",
+		.of_match_table = of_clk_gate_ids,
+	},
+	.probe = of_clk_probe,
+	.remove = of_clk_remove,
+};
+builtin_platform_driver(of_clk_gate_driver);
+#endif
-- 
2.39.2