[PATCH v2 3/4] clk: ralink: make system controller node a reset provider

From: Sergio Paracuellos
Date: Wed Oct 06 2021 - 07:25:17 EST


MT7621 system controller node is already providing the clocks for the whole
system but must also serve as a reset provider. Hence, add reset controller
related code to the clock driver itself.

Signed-off-by: Sergio Paracuellos <sergio.paracuellos@xxxxxxxxx>
---
drivers/clk/ralink/clk-mt7621.c | 79 +++++++++++++++++++++++++++++++++
1 file changed, 79 insertions(+)

diff --git a/drivers/clk/ralink/clk-mt7621.c b/drivers/clk/ralink/clk-mt7621.c
index a2c045390f00..7a474bb4c877 100644
--- a/drivers/clk/ralink/clk-mt7621.c
+++ b/drivers/clk/ralink/clk-mt7621.c
@@ -11,14 +11,17 @@
#include <linux/mfd/syscon.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
+#include <linux/reset-controller.h>
#include <linux/slab.h>
#include <dt-bindings/clock/mt7621-clk.h>
+#include <dt-bindings/reset/mt7621-reset.h>

/* Configuration registers */
#define SYSC_REG_SYSTEM_CONFIG0 0x10
#define SYSC_REG_SYSTEM_CONFIG1 0x14
#define SYSC_REG_CLKCFG0 0x2c
#define SYSC_REG_CLKCFG1 0x30
+#define SYSC_REG_RESET_CTRL 0x34
#define SYSC_REG_CUR_CLK_STS 0x44
#define MEMC_REG_CPU_PLL 0x648

@@ -398,6 +401,76 @@ static void __init mt7621_clk_init(struct device_node *node)
}
CLK_OF_DECLARE_DRIVER(mt7621_clk, "mediatek,mt7621-sysc", mt7621_clk_init);

+struct mt7621_rst {
+ struct reset_controller_dev rcdev;
+ struct regmap *sysc;
+};
+
+static struct mt7621_rst *to_mt7621_rst(struct reset_controller_dev *dev)
+{
+ return container_of(dev, struct mt7621_rst, rcdev);
+}
+
+static int mt7621_assert_device(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct mt7621_rst *data = to_mt7621_rst(rcdev);
+ struct regmap *sysc = data->sysc;
+
+ if (id == MT7621_RST_SYS)
+ return -EINVAL;
+
+ return regmap_update_bits(sysc, SYSC_REG_RESET_CTRL, BIT(id), BIT(id));
+}
+
+static int mt7621_deassert_device(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ struct mt7621_rst *data = to_mt7621_rst(rcdev);
+ struct regmap *sysc = data->sysc;
+
+ if (id == MT7621_RST_SYS)
+ return -EINVAL;
+
+ return regmap_update_bits(sysc, SYSC_REG_RESET_CTRL, BIT(id), 0);
+}
+
+static int mt7621_reset_device(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ int ret;
+
+ ret = mt7621_assert_device(rcdev, id);
+ if (ret < 0)
+ return ret;
+
+ return mt7621_deassert_device(rcdev, id);
+}
+
+static const struct reset_control_ops reset_ops = {
+ .reset = mt7621_reset_device,
+ .assert = mt7621_assert_device,
+ .deassert = mt7621_deassert_device
+};
+
+static int mt7621_reset_init(struct device *dev, struct regmap *sysc)
+{
+ struct mt7621_rst *rst_data;
+
+ rst_data = devm_kzalloc(dev, sizeof(*rst_data), GFP_KERNEL);
+ if (!rst_data)
+ return -ENOMEM;
+
+ rst_data->sysc = sysc;
+ rst_data->rcdev.ops = &reset_ops;
+ rst_data->rcdev.owner = THIS_MODULE;
+ rst_data->rcdev.nr_resets = 32;
+ rst_data->rcdev.of_reset_n_cells = 1;
+ rst_data->rcdev.of_node = dev_of_node(dev);
+
+ return devm_reset_controller_register(dev, &rst_data->rcdev);
+}
+
static int mt7621_clk_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
@@ -424,6 +497,12 @@ static int mt7621_clk_probe(struct platform_device *pdev)
return ret;
}

+ ret = mt7621_reset_init(dev, priv->sysc);
+ if (ret) {
+ pr_err("Could not init reset controller\n");
+ return ret;
+ }
+
count = ARRAY_SIZE(mt7621_clks_base) +
ARRAY_SIZE(mt7621_fixed_clks) + ARRAY_SIZE(mt7621_gates);
clk_data = devm_kzalloc(dev, struct_size(clk_data, hws, count),
--
2.33.0