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1// SPDX-License-Identifier: GPL-2.0-or-later2//3// Actions Semi Owl SoCs Reset Management Unit driver4//5// Copyright (c) 2018 Linaro Ltd.6// Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>7 8#include <linux/delay.h>9#include <linux/regmap.h>10#include <linux/reset-controller.h>11 12#include "owl-reset.h"13 14static int owl_reset_assert(struct reset_controller_dev *rcdev,15 unsigned long id)16{17 struct owl_reset *reset = to_owl_reset(rcdev);18 const struct owl_reset_map *map = &reset->reset_map[id];19 20 return regmap_update_bits(reset->regmap, map->reg, map->bit, 0);21}22 23static int owl_reset_deassert(struct reset_controller_dev *rcdev,24 unsigned long id)25{26 struct owl_reset *reset = to_owl_reset(rcdev);27 const struct owl_reset_map *map = &reset->reset_map[id];28 29 return regmap_update_bits(reset->regmap, map->reg, map->bit, map->bit);30}31 32static int owl_reset_reset(struct reset_controller_dev *rcdev,33 unsigned long id)34{35 owl_reset_assert(rcdev, id);36 udelay(1);37 owl_reset_deassert(rcdev, id);38 39 return 0;40}41 42static int owl_reset_status(struct reset_controller_dev *rcdev,43 unsigned long id)44{45 struct owl_reset *reset = to_owl_reset(rcdev);46 const struct owl_reset_map *map = &reset->reset_map[id];47 u32 reg;48 int ret;49 50 ret = regmap_read(reset->regmap, map->reg, ®);51 if (ret)52 return ret;53 54 /*55 * The reset control API expects 0 if reset is not asserted,56 * which is the opposite of what our hardware uses.57 */58 return !(map->bit & reg);59}60 61const struct reset_control_ops owl_reset_ops = {62 .assert = owl_reset_assert,63 .deassert = owl_reset_deassert,64 .reset = owl_reset_reset,65 .status = owl_reset_status,66};67