[PATCH V2 09/12] clk: mediatek: reset: Add support for input offset and bit from DT

[Rex-BC Chen <rex-bc.chen@mediatek.com>]

To use the clock reset function easier, we implement the of_xlate.
This function is only adopted in version MTK_SET_CLR because of
the method of id calculation.

There is no impact for original use. If the argument number is not
larger than 1, it will return original id.

With this implementation if we want to set offset 0x120 and bit 16,
we can just write something like "resets = <&infra_rst 0x120 16>;".

Signed-off-by: Rex-BC Chen <rex-bc.chen@mediatek.com>
---
 drivers/clk/mediatek/reset.c | 24 ++++++++++++++++++++++++
 drivers/clk/mediatek/reset.h |  1 +
 2 files changed, 25 insertions(+)

diff --git a/drivers/clk/mediatek/reset.c b/drivers/clk/mediatek/reset.c
index 1173111af3ab..dbe812062bf5 100644
--- a/drivers/clk/mediatek/reset.c
+++ b/drivers/clk/mediatek/reset.c
@@ -59,6 +59,20 @@ static const struct reset_control_ops mtk_reset_ops_set_clr = {
 	.reset = mtk_reset_set_clr,
 };
 
+static int reset_xlate(struct reset_controller_dev *rcdev,
+		       const struct of_phandle_args *reset_spec)
+{
+	unsigned int offset, bit;
+
+	if (reset_spec->args_count <= 1)
+		return reset_spec->args[0];
+
+	offset = reset_spec->args[0];
+	bit = reset_spec->args[1];
+
+	return (offset >> 4) * 32 + bit;
+}
+
 static const struct reset_control_ops *rst_op[MTK_RST_MAX] = {
 	[MTK_RST_SIMPLE] = &reset_simple_ops,
 	[MTK_RST_SET_CLR] = &mtk_reset_ops_set_clr,
@@ -98,6 +112,11 @@ int mtk_clk_register_rst_ctrl(struct device_node *np,
 	data->rcdev.ops = rst_op[desc->version];
 	data->rcdev.of_node = np;
 
+	if (desc->version == MTK_RST_SET_CLR) {
+		data->rcdev.of_reset_n_cells = max(desc->reset_n_cells, 1);
+		data->rcdev.of_xlate = reset_xlate;
+	}
+
 	ret = reset_controller_register(&data->rcdev);
 	if (ret) {
 		pr_err("could not register reset controller: %d\n", ret);
@@ -143,6 +162,11 @@ int mtk_clk_register_rst_ctrl_with_dev(struct device *dev,
 	data->rcdev.of_node = np;
 	data->rcdev.dev = dev;
 
+	if (desc->version == MTK_RST_SET_CLR) {
+		data->rcdev.of_reset_n_cells = max(desc->reset_n_cells, 1);
+		data->rcdev.of_xlate = reset_xlate;
+	}
+
 	ret = devm_reset_controller_register(dev, &data->rcdev);
 	if (ret)
 		dev_err(dev, "could not register reset controller: %d\n", ret);
diff --git a/drivers/clk/mediatek/reset.h b/drivers/clk/mediatek/reset.h
index 30559bf45f7e..4cfc281fc50d 100644
--- a/drivers/clk/mediatek/reset.h
+++ b/drivers/clk/mediatek/reset.h
@@ -19,6 +19,7 @@ struct mtk_clk_rst_desc {
 	u8 version;
 	u32 reg_num;
 	u16 reg_ofs;
+	int reset_n_cells;
 };
 
 struct mtk_clk_rst_data {
-- 
2.18.0