1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2016 Maxime Ripard
4 * Maxime Ripard <maxime.ripard@free-electrons.com>
5 */
6
7#include <linux/delay.h>
8#include <linux/io.h>
9#include <linux/reset-controller.h>
10
11#include "ccu_reset.h"
12
13static int ccu_reset_assert(struct reset_controller_dev *rcdev,
14			    unsigned long id)
15{
16	struct ccu_reset *ccu = rcdev_to_ccu_reset(rcdev);
17	const struct ccu_reset_map *map = &ccu->reset_map[id];
18	unsigned long flags;
19	u32 reg;
20
21	spin_lock_irqsave(ccu->lock, flags);
22
23	reg = readl(ccu->base + map->reg);
24	writel(reg & ~map->bit, ccu->base + map->reg);
25
26	spin_unlock_irqrestore(ccu->lock, flags);
27
28	return 0;
29}
30
31static int ccu_reset_deassert(struct reset_controller_dev *rcdev,
32			      unsigned long id)
33{
34	struct ccu_reset *ccu = rcdev_to_ccu_reset(rcdev);
35	const struct ccu_reset_map *map = &ccu->reset_map[id];
36	unsigned long flags;
37	u32 reg;
38
39	spin_lock_irqsave(ccu->lock, flags);
40
41	reg = readl(ccu->base + map->reg);
42	writel(reg | map->bit, ccu->base + map->reg);
43
44	spin_unlock_irqrestore(ccu->lock, flags);
45
46	return 0;
47}
48
49static int ccu_reset_reset(struct reset_controller_dev *rcdev,
50			   unsigned long id)
51{
52	ccu_reset_assert(rcdev, id);
53	udelay(10);
54	ccu_reset_deassert(rcdev, id);
55
56	return 0;
57}
58
59static int ccu_reset_status(struct reset_controller_dev *rcdev,
60			    unsigned long id)
61{
62	struct ccu_reset *ccu = rcdev_to_ccu_reset(rcdev);
63	const struct ccu_reset_map *map = &ccu->reset_map[id];
64
65	/*
66	 * The reset control API expects 0 if reset is not asserted,
67	 * which is the opposite of what our hardware uses.
68	 */
69	return !(map->bit & readl(ccu->base + map->reg));
70}
71
72const struct reset_control_ops ccu_reset_ops = {
73	.assert		= ccu_reset_assert,
74	.deassert	= ccu_reset_deassert,
75	.reset		= ccu_reset_reset,
76	.status		= ccu_reset_status,
77};
78EXPORT_SYMBOL_NS_GPL(ccu_reset_ops, SUNXI_CCU);
79