mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-15 23:14:31 +08:00
e5c73bdb13
The bcm6345_reset_ops structure is never modified. Make it const. Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
136 lines
3.5 KiB
C
136 lines
3.5 KiB
C
// SPDX-License-Identifier: GPL-2.0-or-later
|
|
/*
|
|
* BCM6345 Reset Controller Driver
|
|
*
|
|
* Copyright (C) 2020 Álvaro Fernández Rojas <noltari@gmail.com>
|
|
*/
|
|
|
|
#include <linux/delay.h>
|
|
#include <linux/init.h>
|
|
#include <linux/io.h>
|
|
#include <linux/mod_devicetable.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/reset-controller.h>
|
|
|
|
#define BCM6345_RESET_NUM 32
|
|
#define BCM6345_RESET_SLEEP_MIN_US 10000
|
|
#define BCM6345_RESET_SLEEP_MAX_US 20000
|
|
|
|
struct bcm6345_reset {
|
|
struct reset_controller_dev rcdev;
|
|
void __iomem *base;
|
|
spinlock_t lock;
|
|
};
|
|
|
|
static inline struct bcm6345_reset *
|
|
to_bcm6345_reset(struct reset_controller_dev *rcdev)
|
|
{
|
|
return container_of(rcdev, struct bcm6345_reset, rcdev);
|
|
}
|
|
|
|
static int bcm6345_reset_update(struct reset_controller_dev *rcdev,
|
|
unsigned long id, bool assert)
|
|
{
|
|
struct bcm6345_reset *bcm6345_reset = to_bcm6345_reset(rcdev);
|
|
unsigned long flags;
|
|
uint32_t val;
|
|
|
|
spin_lock_irqsave(&bcm6345_reset->lock, flags);
|
|
val = __raw_readl(bcm6345_reset->base);
|
|
if (assert)
|
|
val &= ~BIT(id);
|
|
else
|
|
val |= BIT(id);
|
|
__raw_writel(val, bcm6345_reset->base);
|
|
spin_unlock_irqrestore(&bcm6345_reset->lock, flags);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int bcm6345_reset_assert(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
return bcm6345_reset_update(rcdev, id, true);
|
|
}
|
|
|
|
static int bcm6345_reset_deassert(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
return bcm6345_reset_update(rcdev, id, false);
|
|
}
|
|
|
|
static int bcm6345_reset_reset(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
bcm6345_reset_update(rcdev, id, true);
|
|
usleep_range(BCM6345_RESET_SLEEP_MIN_US,
|
|
BCM6345_RESET_SLEEP_MAX_US);
|
|
|
|
bcm6345_reset_update(rcdev, id, false);
|
|
/*
|
|
* Ensure component is taken out reset state by sleeping also after
|
|
* deasserting the reset. Otherwise, the component may not be ready
|
|
* for operation.
|
|
*/
|
|
usleep_range(BCM6345_RESET_SLEEP_MIN_US,
|
|
BCM6345_RESET_SLEEP_MAX_US);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int bcm6345_reset_status(struct reset_controller_dev *rcdev,
|
|
unsigned long id)
|
|
{
|
|
struct bcm6345_reset *bcm6345_reset = to_bcm6345_reset(rcdev);
|
|
|
|
return !(__raw_readl(bcm6345_reset->base) & BIT(id));
|
|
}
|
|
|
|
static const struct reset_control_ops bcm6345_reset_ops = {
|
|
.assert = bcm6345_reset_assert,
|
|
.deassert = bcm6345_reset_deassert,
|
|
.reset = bcm6345_reset_reset,
|
|
.status = bcm6345_reset_status,
|
|
};
|
|
|
|
static int bcm6345_reset_probe(struct platform_device *pdev)
|
|
{
|
|
struct bcm6345_reset *bcm6345_reset;
|
|
|
|
bcm6345_reset = devm_kzalloc(&pdev->dev,
|
|
sizeof(*bcm6345_reset), GFP_KERNEL);
|
|
if (!bcm6345_reset)
|
|
return -ENOMEM;
|
|
|
|
platform_set_drvdata(pdev, bcm6345_reset);
|
|
|
|
bcm6345_reset->base = devm_platform_ioremap_resource(pdev, 0);
|
|
if (IS_ERR(bcm6345_reset->base))
|
|
return PTR_ERR(bcm6345_reset->base);
|
|
|
|
spin_lock_init(&bcm6345_reset->lock);
|
|
bcm6345_reset->rcdev.ops = &bcm6345_reset_ops;
|
|
bcm6345_reset->rcdev.owner = THIS_MODULE;
|
|
bcm6345_reset->rcdev.of_node = pdev->dev.of_node;
|
|
bcm6345_reset->rcdev.of_reset_n_cells = 1;
|
|
bcm6345_reset->rcdev.nr_resets = BCM6345_RESET_NUM;
|
|
|
|
return devm_reset_controller_register(&pdev->dev,
|
|
&bcm6345_reset->rcdev);
|
|
}
|
|
|
|
static const struct of_device_id bcm6345_reset_of_match[] = {
|
|
{ .compatible = "brcm,bcm6345-reset" },
|
|
{ /* sentinel */ },
|
|
};
|
|
|
|
static struct platform_driver bcm6345_reset_driver = {
|
|
.probe = bcm6345_reset_probe,
|
|
.driver = {
|
|
.name = "bcm6345-reset",
|
|
.of_match_table = bcm6345_reset_of_match,
|
|
.suppress_bind_attrs = true,
|
|
},
|
|
};
|
|
builtin_platform_driver(bcm6345_reset_driver);
|