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-rw-r--r--drivers/clk/mediatek/reset.c233
1 files changed, 233 insertions, 0 deletions
diff --git a/drivers/clk/mediatek/reset.c b/drivers/clk/mediatek/reset.c
new file mode 100644
index 000000000..290ceda84
--- /dev/null
+++ b/drivers/clk/mediatek/reset.c
@@ -0,0 +1,233 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2014 MediaTek Inc.
+ */
+
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#include "reset.h"
+
+static inline struct mtk_clk_rst_data *to_mtk_clk_rst_data(struct reset_controller_dev *rcdev)
+{
+ return container_of(rcdev, struct mtk_clk_rst_data, rcdev);
+}
+
+static int mtk_reset_update(struct reset_controller_dev *rcdev,
+ unsigned long id, bool deassert)
+{
+ struct mtk_clk_rst_data *data = to_mtk_clk_rst_data(rcdev);
+ unsigned int val = deassert ? 0 : ~0;
+
+ return regmap_update_bits(data->regmap,
+ data->desc->rst_bank_ofs[id / RST_NR_PER_BANK],
+ BIT(id % RST_NR_PER_BANK), val);
+}
+
+static int mtk_reset_assert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return mtk_reset_update(rcdev, id, false);
+}
+
+static int mtk_reset_deassert(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return mtk_reset_update(rcdev, id, true);
+}
+
+static int mtk_reset(struct reset_controller_dev *rcdev, unsigned long id)
+{
+ int ret;
+
+ ret = mtk_reset_assert(rcdev, id);
+ if (ret)
+ return ret;
+
+ return mtk_reset_deassert(rcdev, id);
+}
+
+static int mtk_reset_update_set_clr(struct reset_controller_dev *rcdev,
+ unsigned long id, bool deassert)
+{
+ struct mtk_clk_rst_data *data = to_mtk_clk_rst_data(rcdev);
+ unsigned int deassert_ofs = deassert ? 0x4 : 0;
+
+ return regmap_write(data->regmap,
+ data->desc->rst_bank_ofs[id / RST_NR_PER_BANK] +
+ deassert_ofs,
+ BIT(id % RST_NR_PER_BANK));
+}
+
+static int mtk_reset_assert_set_clr(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return mtk_reset_update_set_clr(rcdev, id, false);
+}
+
+static int mtk_reset_deassert_set_clr(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ return mtk_reset_update_set_clr(rcdev, id, true);
+}
+
+static int mtk_reset_set_clr(struct reset_controller_dev *rcdev,
+ unsigned long id)
+{
+ int ret;
+
+ ret = mtk_reset_assert_set_clr(rcdev, id);
+ if (ret)
+ return ret;
+ return mtk_reset_deassert_set_clr(rcdev, id);
+}
+
+static const struct reset_control_ops mtk_reset_ops = {
+ .assert = mtk_reset_assert,
+ .deassert = mtk_reset_deassert,
+ .reset = mtk_reset,
+};
+
+static const struct reset_control_ops mtk_reset_ops_set_clr = {
+ .assert = mtk_reset_assert_set_clr,
+ .deassert = mtk_reset_deassert_set_clr,
+ .reset = mtk_reset_set_clr,
+};
+
+static int reset_xlate(struct reset_controller_dev *rcdev,
+ const struct of_phandle_args *reset_spec)
+{
+ struct mtk_clk_rst_data *data = to_mtk_clk_rst_data(rcdev);
+
+ if (reset_spec->args[0] >= rcdev->nr_resets ||
+ reset_spec->args[0] >= data->desc->rst_idx_map_nr)
+ return -EINVAL;
+
+ return data->desc->rst_idx_map[reset_spec->args[0]];
+}
+
+int mtk_register_reset_controller(struct device_node *np,
+ const struct mtk_clk_rst_desc *desc)
+{
+ struct regmap *regmap;
+ const struct reset_control_ops *rcops = NULL;
+ struct mtk_clk_rst_data *data;
+ int ret;
+
+ if (!desc) {
+ pr_err("mtk clock reset desc is NULL\n");
+ return -EINVAL;
+ }
+
+ switch (desc->version) {
+ case MTK_RST_SIMPLE:
+ rcops = &mtk_reset_ops;
+ break;
+ case MTK_RST_SET_CLR:
+ rcops = &mtk_reset_ops_set_clr;
+ break;
+ default:
+ pr_err("Unknown reset version %d\n", desc->version);
+ return -EINVAL;
+ }
+
+ regmap = device_node_to_regmap(np);
+ if (IS_ERR(regmap)) {
+ pr_err("Cannot find regmap for %pOF: %pe\n", np, regmap);
+ return -EINVAL;
+ }
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->desc = desc;
+ data->regmap = regmap;
+ data->rcdev.owner = THIS_MODULE;
+ data->rcdev.ops = rcops;
+ data->rcdev.of_node = np;
+
+ if (data->desc->rst_idx_map_nr > 0) {
+ data->rcdev.of_reset_n_cells = 1;
+ data->rcdev.nr_resets = desc->rst_idx_map_nr;
+ data->rcdev.of_xlate = reset_xlate;
+ } else {
+ data->rcdev.nr_resets = desc->rst_bank_nr * RST_NR_PER_BANK;
+ }
+
+ ret = reset_controller_register(&data->rcdev);
+ if (ret) {
+ pr_err("could not register reset controller: %d\n", ret);
+ kfree(data);
+ return ret;
+ }
+
+ return 0;
+}
+
+int mtk_register_reset_controller_with_dev(struct device *dev,
+ const struct mtk_clk_rst_desc *desc)
+{
+ struct device_node *np = dev->of_node;
+ struct regmap *regmap;
+ const struct reset_control_ops *rcops = NULL;
+ struct mtk_clk_rst_data *data;
+ int ret;
+
+ if (!desc) {
+ dev_err(dev, "mtk clock reset desc is NULL\n");
+ return -EINVAL;
+ }
+
+ switch (desc->version) {
+ case MTK_RST_SIMPLE:
+ rcops = &mtk_reset_ops;
+ break;
+ case MTK_RST_SET_CLR:
+ rcops = &mtk_reset_ops_set_clr;
+ break;
+ default:
+ dev_err(dev, "Unknown reset version %d\n", desc->version);
+ return -EINVAL;
+ }
+
+ regmap = device_node_to_regmap(np);
+ if (IS_ERR(regmap)) {
+ dev_err(dev, "Cannot find regmap %pe\n", regmap);
+ return -EINVAL;
+ }
+
+ data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->desc = desc;
+ data->regmap = regmap;
+ data->rcdev.owner = THIS_MODULE;
+ data->rcdev.ops = rcops;
+ data->rcdev.of_node = np;
+ data->rcdev.dev = dev;
+
+ if (data->desc->rst_idx_map_nr > 0) {
+ data->rcdev.of_reset_n_cells = 1;
+ data->rcdev.nr_resets = desc->rst_idx_map_nr;
+ data->rcdev.of_xlate = reset_xlate;
+ } else {
+ data->rcdev.nr_resets = desc->rst_bank_nr * RST_NR_PER_BANK;
+ }
+
+ ret = devm_reset_controller_register(dev, &data->rcdev);
+ if (ret) {
+ dev_err(dev, "could not register reset controller: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(mtk_register_reset_controller_with_dev);
+
+MODULE_LICENSE("GPL");