aboutsummaryrefslogtreecommitdiff
path: root/arch/avr32/mach-at32ap/clock.c
blob: 49e7b12fe710848dfa1b4fa18f12978768efa481 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
/*
 * Clock management for AT32AP CPUs
 *
 * Copyright (C) 2006 Atmel Corporation
 *
 * Based on arch/arm/mach-at91rm9200/clock.c
 *   Copyright (C) 2005 David Brownell
 *   Copyright (C) 2005 Ivan Kokshaysky
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/device.h>
#include <linux/string.h>

#include "clock.h"

static spinlock_t clk_lock = SPIN_LOCK_UNLOCKED;

struct clk *clk_get(struct device *dev, const char *id)
{
	int i;

	for (i = 0; i < at32_nr_clocks; i++) {
		struct clk *clk = at32_clock_list[i];

		if (clk->dev == dev && strcmp(id, clk->name) == 0)
			return clk;
	}

	return ERR_PTR(-ENOENT);
}
EXPORT_SYMBOL(clk_get);

void clk_put(struct clk *clk)
{
	/* clocks are static for now, we can't free them */
}
EXPORT_SYMBOL(clk_put);

static void __clk_enable(struct clk *clk)
{
	if (clk->parent)
		__clk_enable(clk->parent);
	if (clk->users++ == 0 && clk->mode)
		clk->mode(clk, 1);
}

int clk_enable(struct clk *clk)
{
	unsigned long flags;

	spin_lock_irqsave(&clk_lock, flags);
	__clk_enable(clk);
	spin_unlock_irqrestore(&clk_lock, flags);

	return 0;
}
EXPORT_SYMBOL(clk_enable);

static void __clk_disable(struct clk *clk)
{
	if (clk->users == 0) {
		printk(KERN_ERR "%s: mismatched disable\n", clk->name);
		WARN_ON(1);
		return;
	}

	if (--clk->users == 0 && clk->mode)
		clk->mode(clk, 0);
	if (clk->parent)
		__clk_disable(clk->parent);
}

void clk_disable(struct clk *clk)
{
	unsigned long flags;

	spin_lock_irqsave(&clk_lock, flags);
	__clk_disable(clk);
	spin_unlock_irqrestore(&clk_lock, flags);
}
EXPORT_SYMBOL(clk_disable);

unsigned long clk_get_rate(struct clk *clk)
{
	unsigned long flags;
	unsigned long rate;

	spin_lock_irqsave(&clk_lock, flags);
	rate = clk->get_rate(clk);
	spin_unlock_irqrestore(&clk_lock, flags);

	return rate;
}
EXPORT_SYMBOL(clk_get_rate);

long clk_round_rate(struct clk *clk, unsigned long rate)
{
	unsigned long flags, actual_rate;

	if (!clk->set_rate)
		return -ENOSYS;

	spin_lock_irqsave(&clk_lock, flags);
	actual_rate = clk->set_rate(clk, rate, 0);
	spin_unlock_irqrestore(&clk_lock, flags);

	return actual_rate;
}
EXPORT_SYMBOL(clk_round_rate);

int clk_set_rate(struct clk *clk, unsigned long rate)
{
	unsigned long flags;
	long ret;

	if (!clk->set_rate)
		return -ENOSYS;

	spin_lock_irqsave(&clk_lock, flags);
	ret = clk->set_rate(clk, rate, 1);
	spin_unlock_irqrestore(&clk_lock, flags);

	return (ret < 0) ? ret : 0;
}
EXPORT_SYMBOL(clk_set_rate);

int clk_set_parent(struct clk *clk, struct clk *parent)
{
	unsigned long flags;
	int ret;

	if (!clk->set_parent)
		return -ENOSYS;

	spin_lock_irqsave(&clk_lock, flags);
	ret = clk->set_parent(clk, parent);
	spin_unlock_irqrestore(&clk_lock, flags);

	return ret;
}
EXPORT_SYMBOL(clk_set_parent);

struct clk *clk_get_parent(struct clk *clk)
{
	return clk->parent;
}
EXPORT_SYMBOL(clk_get_parent);