linux/drivers/reset/hisilicon/reset-hi3660.c

123 lines
3.0 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (c) 2016-2017 Linaro Ltd.
* Copyright (c) 2016-2017 HiSilicon Technologies Co., Ltd.
*/
#include <linux/kernel.h>
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/reset-controller.h>
struct hi3660_reset_controller {
struct reset_controller_dev rst;
struct regmap *map;
};
#define to_hi3660_reset_controller(_rst) \
container_of(_rst, struct hi3660_reset_controller, rst)
static int hi3660_reset_program_hw(struct reset_controller_dev *rcdev,
unsigned long idx, bool assert)
{
struct hi3660_reset_controller *rc = to_hi3660_reset_controller(rcdev);
unsigned int offset = idx >> 8;
unsigned int mask = BIT(idx & 0x1f);
if (assert)
return regmap_write(rc->map, offset, mask);
else
return regmap_write(rc->map, offset + 4, mask);
}
static int hi3660_reset_assert(struct reset_controller_dev *rcdev,
unsigned long idx)
{
return hi3660_reset_program_hw(rcdev, idx, true);
}
static int hi3660_reset_deassert(struct reset_controller_dev *rcdev,
unsigned long idx)
{
return hi3660_reset_program_hw(rcdev, idx, false);
}
static int hi3660_reset_dev(struct reset_controller_dev *rcdev,
unsigned long idx)
{
int err;
err = hi3660_reset_assert(rcdev, idx);
if (err)
return err;
return hi3660_reset_deassert(rcdev, idx);
}
static struct reset_control_ops hi3660_reset_ops = {
.reset = hi3660_reset_dev,
.assert = hi3660_reset_assert,
.deassert = hi3660_reset_deassert,
};
static int hi3660_reset_xlate(struct reset_controller_dev *rcdev,
const struct of_phandle_args *reset_spec)
{
unsigned int offset, bit;
offset = reset_spec->args[0];
bit = reset_spec->args[1];
return (offset << 8) | bit;
}
static int hi3660_reset_probe(struct platform_device *pdev)
{
struct hi3660_reset_controller *rc;
struct device_node *np = pdev->dev.of_node;
struct device *dev = &pdev->dev;
rc = devm_kzalloc(dev, sizeof(*rc), GFP_KERNEL);
if (!rc)
return -ENOMEM;
rc->map = syscon_regmap_lookup_by_phandle(np, "hisi,rst-syscon");
if (IS_ERR(rc->map)) {
dev_err(dev, "failed to get hi3660,rst-syscon\n");
return PTR_ERR(rc->map);
}
rc->rst.ops = &hi3660_reset_ops,
rc->rst.of_node = np;
rc->rst.of_reset_n_cells = 2;
rc->rst.of_xlate = hi3660_reset_xlate;
return reset_controller_register(&rc->rst);
}
static const struct of_device_id hi3660_reset_match[] = {
{ .compatible = "hisilicon,hi3660-reset", },
{},
};
MODULE_DEVICE_TABLE(of, hi3660_reset_match);
static struct platform_driver hi3660_reset_driver = {
.probe = hi3660_reset_probe,
.driver = {
.name = "hi3660-reset",
.of_match_table = hi3660_reset_match,
},
};
static int __init hi3660_reset_init(void)
{
return platform_driver_register(&hi3660_reset_driver);
}
arch_initcall(hi3660_reset_init);
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:hi3660-reset");
MODULE_DESCRIPTION("HiSilicon Hi3660 Reset Driver");