mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-27 03:10:12 +00:00
![Yang Yingliang](/assets/img/avatar_default.png)
Use devm_reset_controller_register() for the reset controller registration. Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Link: https://lore.kernel.org/r/20210517032648.2969609-1-yangyingliang@huawei.com Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
210 lines
5.2 KiB
C
210 lines
5.2 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
*
|
|
* Copyright (C) 2010 John Crispin <blogic@phrozen.org>
|
|
* Copyright (C) 2013-2015 Lantiq Beteiligungs-GmbH & Co.KG
|
|
* Copyright (C) 2016 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
|
|
* Copyright (C) 2017 Hauke Mehrtens <hauke@hauke-m.de>
|
|
*/
|
|
|
|
#include <linux/mfd/syscon.h>
|
|
#include <linux/module.h>
|
|
#include <linux/regmap.h>
|
|
#include <linux/reset-controller.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/of_platform.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/property.h>
|
|
|
|
#define LANTIQ_RCU_RESET_TIMEOUT 10000
|
|
|
|
struct lantiq_rcu_reset_priv {
|
|
struct reset_controller_dev rcdev;
|
|
struct device *dev;
|
|
struct regmap *regmap;
|
|
u32 reset_offset;
|
|
u32 status_offset;
|
|
};
|
|
|
|
static struct lantiq_rcu_reset_priv *to_lantiq_rcu_reset_priv(
|
|
struct reset_controller_dev *rcdev)
|
|
{
|
|
return container_of(rcdev, struct lantiq_rcu_reset_priv, rcdev);
|
|
}
|
|
|
|
static int lantiq_rcu_reset_status(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
struct lantiq_rcu_reset_priv *priv = to_lantiq_rcu_reset_priv(rcdev);
|
|
unsigned int status = (id >> 8) & 0x1f;
|
|
u32 val;
|
|
int ret;
|
|
|
|
ret = regmap_read(priv->regmap, priv->status_offset, &val);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return !!(val & BIT(status));
|
|
}
|
|
|
|
static int lantiq_rcu_reset_status_timeout(struct reset_controller_dev *rcdev,
|
|
unsigned long id, bool assert)
|
|
{
|
|
int ret;
|
|
int retry = LANTIQ_RCU_RESET_TIMEOUT;
|
|
|
|
do {
|
|
ret = lantiq_rcu_reset_status(rcdev, id);
|
|
if (ret < 0)
|
|
return ret;
|
|
if (ret == assert)
|
|
return 0;
|
|
usleep_range(20, 40);
|
|
} while (--retry);
|
|
|
|
return -ETIMEDOUT;
|
|
}
|
|
|
|
static int lantiq_rcu_reset_update(struct reset_controller_dev *rcdev,
|
|
unsigned long id, bool assert)
|
|
{
|
|
struct lantiq_rcu_reset_priv *priv = to_lantiq_rcu_reset_priv(rcdev);
|
|
unsigned int set = id & 0x1f;
|
|
u32 val = assert ? BIT(set) : 0;
|
|
int ret;
|
|
|
|
ret = regmap_update_bits(priv->regmap, priv->reset_offset, BIT(set),
|
|
val);
|
|
if (ret) {
|
|
dev_err(priv->dev, "Failed to set reset bit %u\n", set);
|
|
return ret;
|
|
}
|
|
|
|
|
|
ret = lantiq_rcu_reset_status_timeout(rcdev, id, assert);
|
|
if (ret)
|
|
dev_err(priv->dev, "Failed to %s bit %u\n",
|
|
assert ? "assert" : "deassert", set);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int lantiq_rcu_reset_assert(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
return lantiq_rcu_reset_update(rcdev, id, true);
|
|
}
|
|
|
|
static int lantiq_rcu_reset_deassert(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
return lantiq_rcu_reset_update(rcdev, id, false);
|
|
}
|
|
|
|
static int lantiq_rcu_reset_reset(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
int ret;
|
|
|
|
ret = lantiq_rcu_reset_assert(rcdev, id);
|
|
if (ret)
|
|
return ret;
|
|
|
|
return lantiq_rcu_reset_deassert(rcdev, id);
|
|
}
|
|
|
|
static const struct reset_control_ops lantiq_rcu_reset_ops = {
|
|
.assert = lantiq_rcu_reset_assert,
|
|
.deassert = lantiq_rcu_reset_deassert,
|
|
.status = lantiq_rcu_reset_status,
|
|
.reset = lantiq_rcu_reset_reset,
|
|
};
|
|
|
|
static int lantiq_rcu_reset_of_parse(struct platform_device *pdev,
|
|
struct lantiq_rcu_reset_priv *priv)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
const __be32 *offset;
|
|
|
|
priv->regmap = syscon_node_to_regmap(dev->of_node->parent);
|
|
if (IS_ERR(priv->regmap)) {
|
|
dev_err(&pdev->dev, "Failed to lookup RCU regmap\n");
|
|
return PTR_ERR(priv->regmap);
|
|
}
|
|
|
|
offset = of_get_address(dev->of_node, 0, NULL, NULL);
|
|
if (!offset) {
|
|
dev_err(&pdev->dev, "Failed to get RCU reset offset\n");
|
|
return -ENOENT;
|
|
}
|
|
priv->reset_offset = __be32_to_cpu(*offset);
|
|
|
|
offset = of_get_address(dev->of_node, 1, NULL, NULL);
|
|
if (!offset) {
|
|
dev_err(&pdev->dev, "Failed to get RCU status offset\n");
|
|
return -ENOENT;
|
|
}
|
|
priv->status_offset = __be32_to_cpu(*offset);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int lantiq_rcu_reset_xlate(struct reset_controller_dev *rcdev,
|
|
const struct of_phandle_args *reset_spec)
|
|
{
|
|
unsigned int status, set;
|
|
|
|
set = reset_spec->args[0];
|
|
status = reset_spec->args[1];
|
|
|
|
if (set >= rcdev->nr_resets || status >= rcdev->nr_resets)
|
|
return -EINVAL;
|
|
|
|
return (status << 8) | set;
|
|
}
|
|
|
|
static int lantiq_rcu_reset_probe(struct platform_device *pdev)
|
|
{
|
|
struct lantiq_rcu_reset_priv *priv;
|
|
int err;
|
|
|
|
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
|
|
if (!priv)
|
|
return -ENOMEM;
|
|
|
|
priv->dev = &pdev->dev;
|
|
platform_set_drvdata(pdev, priv);
|
|
|
|
err = lantiq_rcu_reset_of_parse(pdev, priv);
|
|
if (err)
|
|
return err;
|
|
|
|
priv->rcdev.ops = &lantiq_rcu_reset_ops;
|
|
priv->rcdev.owner = THIS_MODULE;
|
|
priv->rcdev.of_node = pdev->dev.of_node;
|
|
priv->rcdev.nr_resets = 32;
|
|
priv->rcdev.of_xlate = lantiq_rcu_reset_xlate;
|
|
priv->rcdev.of_reset_n_cells = 2;
|
|
|
|
return devm_reset_controller_register(&pdev->dev, &priv->rcdev);
|
|
}
|
|
|
|
static const struct of_device_id lantiq_rcu_reset_dt_ids[] = {
|
|
{ .compatible = "lantiq,danube-reset", },
|
|
{ .compatible = "lantiq,xrx200-reset", },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(of, lantiq_rcu_reset_dt_ids);
|
|
|
|
static struct platform_driver lantiq_rcu_reset_driver = {
|
|
.probe = lantiq_rcu_reset_probe,
|
|
.driver = {
|
|
.name = "lantiq-reset",
|
|
.of_match_table = lantiq_rcu_reset_dt_ids,
|
|
},
|
|
};
|
|
module_platform_driver(lantiq_rcu_reset_driver);
|
|
|
|
MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
|
|
MODULE_DESCRIPTION("Lantiq XWAY RCU Reset Controller Driver");
|
|
MODULE_LICENSE("GPL");
|