JustOS/linux-6.13/drivers/reset/amlogic/reset-meson-common.c
justuser 02e73b8cd9 up
2025-01-24 17:00:19 +03:00

143 lines
3.7 KiB
C

// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
/*
* Amlogic Meson Reset core functions
*
* Copyright (c) 2016-2024 BayLibre, SAS.
* Authors: Neil Armstrong <narmstrong@baylibre.com>
* Jerome Brunet <jbrunet@baylibre.com>
*/
#include <linux/device.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/reset-controller.h>
#include "reset-meson.h"
struct meson_reset {
const struct meson_reset_param *param;
struct reset_controller_dev rcdev;
struct regmap *map;
};
static void meson_reset_offset_and_bit(struct meson_reset *data,
unsigned long id,
unsigned int *offset,
unsigned int *bit)
{
unsigned int stride = regmap_get_reg_stride(data->map);
*offset = (id / (stride * BITS_PER_BYTE)) * stride;
*bit = id % (stride * BITS_PER_BYTE);
}
static int meson_reset_reset(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct meson_reset *data =
container_of(rcdev, struct meson_reset, rcdev);
unsigned int offset, bit;
meson_reset_offset_and_bit(data, id, &offset, &bit);
offset += data->param->reset_offset;
return regmap_write(data->map, offset, BIT(bit));
}
static int meson_reset_level(struct reset_controller_dev *rcdev,
unsigned long id, bool assert)
{
struct meson_reset *data =
container_of(rcdev, struct meson_reset, rcdev);
unsigned int offset, bit;
meson_reset_offset_and_bit(data, id, &offset, &bit);
offset += data->param->level_offset;
assert ^= data->param->level_low_reset;
return regmap_update_bits(data->map, offset,
BIT(bit), assert ? BIT(bit) : 0);
}
static int meson_reset_status(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct meson_reset *data =
container_of(rcdev, struct meson_reset, rcdev);
unsigned int val, offset, bit;
meson_reset_offset_and_bit(data, id, &offset, &bit);
offset += data->param->level_offset;
regmap_read(data->map, offset, &val);
val = !!(BIT(bit) & val);
return val ^ data->param->level_low_reset;
}
static int meson_reset_assert(struct reset_controller_dev *rcdev,
unsigned long id)
{
return meson_reset_level(rcdev, id, true);
}
static int meson_reset_deassert(struct reset_controller_dev *rcdev,
unsigned long id)
{
return meson_reset_level(rcdev, id, false);
}
static int meson_reset_level_toggle(struct reset_controller_dev *rcdev,
unsigned long id)
{
int ret;
ret = meson_reset_assert(rcdev, id);
if (ret)
return ret;
return meson_reset_deassert(rcdev, id);
}
const struct reset_control_ops meson_reset_ops = {
.reset = meson_reset_reset,
.assert = meson_reset_assert,
.deassert = meson_reset_deassert,
.status = meson_reset_status,
};
EXPORT_SYMBOL_NS_GPL(meson_reset_ops, "MESON_RESET");
const struct reset_control_ops meson_reset_toggle_ops = {
.reset = meson_reset_level_toggle,
.assert = meson_reset_assert,
.deassert = meson_reset_deassert,
.status = meson_reset_status,
};
EXPORT_SYMBOL_NS_GPL(meson_reset_toggle_ops, "MESON_RESET");
int meson_reset_controller_register(struct device *dev, struct regmap *map,
const struct meson_reset_param *param)
{
struct meson_reset *data;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->param = param;
data->map = map;
data->rcdev.owner = dev->driver->owner;
data->rcdev.nr_resets = param->reset_num;
data->rcdev.ops = data->param->reset_ops;
data->rcdev.of_node = dev->of_node;
return devm_reset_controller_register(dev, &data->rcdev);
}
EXPORT_SYMBOL_NS_GPL(meson_reset_controller_register, "MESON_RESET");
MODULE_DESCRIPTION("Amlogic Meson Reset Core function");
MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
MODULE_LICENSE("Dual BSD/GPL");
MODULE_IMPORT_NS("MESON_RESET");