OpenCloudOS-Kernel/drivers/clk/sunxi-ng/ccu_reset.c

79 lines
1.8 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2016 Maxime Ripard
* Maxime Ripard <maxime.ripard@free-electrons.com>
*/
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/reset-controller.h>
#include "ccu_reset.h"
static int ccu_reset_assert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct ccu_reset *ccu = rcdev_to_ccu_reset(rcdev);
const struct ccu_reset_map *map = &ccu->reset_map[id];
unsigned long flags;
u32 reg;
spin_lock_irqsave(ccu->lock, flags);
reg = readl(ccu->base + map->reg);
writel(reg & ~map->bit, ccu->base + map->reg);
spin_unlock_irqrestore(ccu->lock, flags);
return 0;
}
static int ccu_reset_deassert(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct ccu_reset *ccu = rcdev_to_ccu_reset(rcdev);
const struct ccu_reset_map *map = &ccu->reset_map[id];
unsigned long flags;
u32 reg;
spin_lock_irqsave(ccu->lock, flags);
reg = readl(ccu->base + map->reg);
writel(reg | map->bit, ccu->base + map->reg);
spin_unlock_irqrestore(ccu->lock, flags);
return 0;
}
static int ccu_reset_reset(struct reset_controller_dev *rcdev,
unsigned long id)
{
ccu_reset_assert(rcdev, id);
udelay(10);
ccu_reset_deassert(rcdev, id);
return 0;
}
static int ccu_reset_status(struct reset_controller_dev *rcdev,
unsigned long id)
{
struct ccu_reset *ccu = rcdev_to_ccu_reset(rcdev);
const struct ccu_reset_map *map = &ccu->reset_map[id];
/*
* The reset control API expects 0 if reset is not asserted,
* which is the opposite of what our hardware uses.
*/
return !(map->bit & readl(ccu->base + map->reg));
}
const struct reset_control_ops ccu_reset_ops = {
.assert = ccu_reset_assert,
.deassert = ccu_reset_deassert,
.reset = ccu_reset_reset,
.status = ccu_reset_status,
};
EXPORT_SYMBOL_NS_GPL(ccu_reset_ops, SUNXI_CCU);