xref: /openbmc/linux/drivers/clk/sunxi-ng/ccu_reset.c (revision 293d5b43)
1 /*
2  * Copyright (C) 2016 Maxime Ripard
3  * Maxime Ripard <maxime.ripard@free-electrons.com>
4  *
5  * This program is free software; you can redistribute it and/or
6  * modify it under the terms of the GNU General Public License as
7  * published by the Free Software Foundation; either version 2 of
8  * the License, or (at your option) any later version.
9  */
10 
11 #include <linux/io.h>
12 #include <linux/reset-controller.h>
13 
14 #include "ccu_reset.h"
15 
16 static int ccu_reset_assert(struct reset_controller_dev *rcdev,
17 			    unsigned long id)
18 {
19 	struct ccu_reset *ccu = rcdev_to_ccu_reset(rcdev);
20 	const struct ccu_reset_map *map = &ccu->reset_map[id];
21 	unsigned long flags;
22 	u32 reg;
23 
24 	spin_lock_irqsave(ccu->lock, flags);
25 
26 	reg = readl(ccu->base + map->reg);
27 	writel(reg & ~map->bit, ccu->base + map->reg);
28 
29 	spin_unlock_irqrestore(ccu->lock, flags);
30 
31 	return 0;
32 }
33 
34 static int ccu_reset_deassert(struct reset_controller_dev *rcdev,
35 			      unsigned long id)
36 {
37 	struct ccu_reset *ccu = rcdev_to_ccu_reset(rcdev);
38 	const struct ccu_reset_map *map = &ccu->reset_map[id];
39 	unsigned long flags;
40 	u32 reg;
41 
42 	spin_lock_irqsave(ccu->lock, flags);
43 
44 	reg = readl(ccu->base + map->reg);
45 	writel(reg | map->bit, ccu->base + map->reg);
46 
47 	spin_unlock_irqrestore(ccu->lock, flags);
48 
49 	return 0;
50 }
51 
52 const struct reset_control_ops ccu_reset_ops = {
53 	.assert		= ccu_reset_assert,
54 	.deassert	= ccu_reset_deassert,
55 };
56