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Diffstat (limited to '')
| -rw-r--r-- | drivers/clk/actions/owl-reset.c | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/drivers/clk/actions/owl-reset.c b/drivers/clk/actions/owl-reset.c new file mode 100644 index 000000000..203f8f34a --- /dev/null +++ b/drivers/clk/actions/owl-reset.c @@ -0,0 +1,66 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +// +// Actions Semi Owl SoCs Reset Management Unit driver +// +// Copyright (c) 2018 Linaro Ltd. +// Author: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org> + +#include <linux/delay.h> +#include <linux/regmap.h> +#include <linux/reset-controller.h> + +#include "owl-reset.h" + +static int owl_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct owl_reset *reset = to_owl_reset(rcdev); + const struct owl_reset_map *map = &reset->reset_map[id]; + + return regmap_update_bits(reset->regmap, map->reg, map->bit, 0); +} + +static int owl_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct owl_reset *reset = to_owl_reset(rcdev); + const struct owl_reset_map *map = &reset->reset_map[id]; + + return regmap_update_bits(reset->regmap, map->reg, map->bit, map->bit); +} + +static int owl_reset_reset(struct reset_controller_dev *rcdev, + unsigned long id) +{ + owl_reset_assert(rcdev, id); + udelay(1); + owl_reset_deassert(rcdev, id); + + return 0; +} + +static int owl_reset_status(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct owl_reset *reset = to_owl_reset(rcdev); + const struct owl_reset_map *map = &reset->reset_map[id]; + u32 reg; + int ret; + + ret = regmap_read(reset->regmap, map->reg, ®); + if (ret) + return ret; + + /* + * The reset control API expects 0 if reset is not asserted, + * which is the opposite of what our hardware uses. + */ + return !(map->bit & reg); +} + +const struct reset_control_ops owl_reset_ops = { + .assert = owl_reset_assert, + .deassert = owl_reset_deassert, + .reset = owl_reset_reset, + .status = owl_reset_status, +}; |