This driver supports th1520 T-HEAD SoC reset platform device.
Signed-off-by: Kwanghoon Son <k.son@xxxxxxxxxxx>
---
drivers/reset/Kconfig | 10 ++++
drivers/reset/Makefile | 1 +
drivers/reset/reset-th1520.c | 109 +++++++++++++++++++++++++++++++++++
3 files changed, 120 insertions(+)
create mode 100644 drivers/reset/reset-th1520.c
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig
index ccd59ddd7610..ec69e6bbba6e 100644
--- a/drivers/reset/Kconfig
+++ b/drivers/reset/Kconfig
@@ -253,6 +253,16 @@ config RESET_SUNXI
help
This enables the reset driver for Allwinner SoCs.
+config RESET_TH1520
+ bool "TH1520 Reset Driver"
+ depends on (ARCH_THEAD || COMPILE_TEST) && OF
+ select MFD_SYSCON
+ default ARCH_THEAD
+ help
+ Support for the T-HEAD 1520 RISC-V SoC reset controller.
+ Say Y if you want to control reset signals provided by this
+ controller.
+
config RESET_TI_SCI
tristate "TI System Control Interface (TI-SCI) reset driver"
depends on TI_SCI_PROTOCOL || (COMPILE_TEST && TI_SCI_PROTOCOL=n)
diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile
index 8270da8a4baa..5c858e62241a 100644
--- a/drivers/reset/Makefile
+++ b/drivers/reset/Makefile
@@ -33,6 +33,7 @@ obj-$(CONFIG_RESET_SIMPLE) += reset-simple.o
obj-$(CONFIG_RESET_SOCFPGA) += reset-socfpga.o
obj-$(CONFIG_RESET_SUNPLUS) += reset-sunplus.o
obj-$(CONFIG_RESET_SUNXI) += reset-sunxi.o
+obj-$(CONFIG_RESET_TH1520) += reset-th1520.o
obj-$(CONFIG_RESET_TI_SCI) += reset-ti-sci.o
obj-$(CONFIG_RESET_TI_SYSCON) += reset-ti-syscon.o
obj-$(CONFIG_RESET_TI_TPS380X) += reset-tps380x.o
diff --git a/drivers/reset/reset-th1520.c b/drivers/reset/reset-th1520.c
new file mode 100644
index 000000000000..5a89d201fc0c
--- /dev/null
+++ b/drivers/reset/reset-th1520.c
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/mfd/syscon.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+#include <linux/regmap.h>
+#include <dt-bindings/reset/thead,th1520-reset.h>
+
+struct th1520_rst_signal {
+ unsigned int offset, bit;
+};
+
+struct th1520_rst {
+ struct reset_controller_dev rcdev;
+ struct regmap *regmap;
+ const struct th1520_rst_signal *signals;
+};
+
+enum th1520_rst_registers {
+ RST_WDT0 = 0x0034,
+ RST_WDT1 = 0x0038,
+};
+
+static int th1520_reset_update(struct th1520_rst *rst, unsigned long id,
+ unsigned int value)
+{
+ const struct th1520_rst_signal *signal = &rst->signals[id];
+
+ return regmap_update_bits(rst->regmap, signal->offset, signal->bit,
+ value);
+}
+
+static const struct th1520_rst_signal th1520_rst_signals[] = {
+ [TH1520_RESET_WDT0] = { RST_WDT0, BIT(0) },
+ [TH1520_RESET_WDT1] = { RST_WDT1, BIT(0) },
+};
+
+static struct th1520_rst *to_th1520_rst(struct reset_controller_dev *rcdev)
+{
+ return container_of(rcdev, struct th1520_rst, rcdev);
+}
+
+static int th1520_reset_set(struct reset_controller_dev *rcdev,
+ unsigned long id, bool assert)
+{
+ struct th1520_rst *rst = to_th1520_rst(rcdev);
+ const unsigned int bit = rst->signals[id].bit;
+ unsigned int value = assert ? bit : 0;
+
+ return th1520_reset_update(rst, id, value);
+}
+
+static int th1520_reset_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return th1520_reset_set(rcdev, id, false);
+}
+
+static int th1520_reset_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return th1520_reset_set(rcdev, id, true);
+}
+
+static const struct reset_control_ops th1520_rst_ops = {
+ .assert = th1520_reset_assert,
+ .deassert = th1520_reset_deassert,
+};
+
+static int th1520_reset_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct th1520_rst *rst;
+ struct regmap_config config = { .name = "rst" };
+
+ rst = devm_kzalloc(dev, sizeof(*rst), GFP_KERNEL);
+ if (!rst)
+ return -ENOMEM;
+
+ rst->signals = th1520_rst_signals;
+ rst->regmap = syscon_node_to_regmap(dev->of_node);
+ if (IS_ERR(rst->regmap))
+ return PTR_ERR(rst->regmap);
+
+ regmap_attach_dev(dev, rst->regmap, &config);
+
+ rst->rcdev.owner = THIS_MODULE;
+ rst->rcdev.dev = dev;
+ rst->rcdev.of_node = dev->of_node;
+ rst->rcdev.ops = &th1520_rst_ops;
+ rst->rcdev.nr_resets = ARRAY_SIZE(th1520_rst_signals);
+
+ return devm_reset_controller_register(dev, &rst->rcdev);
+}
+
+static const struct of_device_id th1520_reset_dt_ids[] = {
+ { .compatible = "thead,th1520-reset" },
+ { /* sentinel */ },
+};
+
+static struct platform_driver th1520_reset_driver = {
+ .probe = th1520_reset_probe,
+ .driver = {
+ .name = "th1520-reset",
+ .of_match_table = th1520_reset_dt_ids,
+ },
+};
+builtin_platform_driver(th1520_reset_driver);
--
2.34.1
