diff options
Diffstat (limited to '')
-rw-r--r-- | drivers/clk/mediatek/reset.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/drivers/clk/mediatek/reset.c b/drivers/clk/mediatek/reset.c new file mode 100644 index 000000000..89916acf0 --- /dev/null +++ b/drivers/clk/mediatek/reset.c @@ -0,0 +1,139 @@ +// 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/reset-controller.h> +#include <linux/slab.h> + +#include "clk-mtk.h" + +struct mtk_reset { + struct regmap *regmap; + int regofs; + struct reset_controller_dev rcdev; +}; + +static int mtk_reset_assert_set_clr(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct mtk_reset *data = container_of(rcdev, struct mtk_reset, rcdev); + unsigned int reg = data->regofs + ((id / 32) << 4); + + return regmap_write(data->regmap, reg, BIT(id % 32)); +} + +static int mtk_reset_deassert_set_clr(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct mtk_reset *data = container_of(rcdev, struct mtk_reset, rcdev); + unsigned int reg = data->regofs + ((id / 32) << 4) + 0x4; + + return regmap_write(data->regmap, reg, BIT(id % 32)); +} + +static int mtk_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct mtk_reset *data = container_of(rcdev, struct mtk_reset, rcdev); + + return regmap_update_bits(data->regmap, data->regofs + ((id / 32) << 2), + BIT(id % 32), ~0); +} + +static int mtk_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct mtk_reset *data = container_of(rcdev, struct mtk_reset, rcdev); + + return regmap_update_bits(data->regmap, data->regofs + ((id / 32) << 2), + BIT(id % 32), 0); +} + +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_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 void mtk_register_reset_controller_common(struct device_node *np, + unsigned int num_regs, int regofs, + const struct reset_control_ops *reset_ops) +{ + struct mtk_reset *data; + int ret; + struct regmap *regmap; + + regmap = syscon_node_to_regmap(np); + if (IS_ERR(regmap)) { + pr_err("Cannot find regmap for %pOF: %ld\n", np, + PTR_ERR(regmap)); + return; + } + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return; + + data->regmap = regmap; + data->regofs = regofs; + data->rcdev.owner = THIS_MODULE; + data->rcdev.nr_resets = num_regs * 32; + data->rcdev.ops = reset_ops; + data->rcdev.of_node = np; + + ret = reset_controller_register(&data->rcdev); + if (ret) { + pr_err("could not register reset controller: %d\n", ret); + kfree(data); + return; + } +} + +void mtk_register_reset_controller(struct device_node *np, + unsigned int num_regs, int regofs) +{ + mtk_register_reset_controller_common(np, num_regs, regofs, + &mtk_reset_ops); +} + +void mtk_register_reset_controller_set_clr(struct device_node *np, + unsigned int num_regs, int regofs) +{ + mtk_register_reset_controller_common(np, num_regs, regofs, + &mtk_reset_ops_set_clr); +} |