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Catalin Marinas8ad68bb2005-10-31 14:25:02 +00001/*
2 * linux/arch/arm/mach-realview/clock.c
3 *
4 * Copyright (C) 2004 ARM Limited.
5 * Written by Deep Blue Solutions Limited.
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11#include <linux/module.h>
12#include <linux/kernel.h>
13#include <linux/list.h>
14#include <linux/errno.h>
15#include <linux/err.h>
Russell Kingf8ce2542006-01-07 16:15:52 +000016#include <linux/clk.h>
Arjan van de Ven00431702006-01-12 18:42:23 +000017#include <linux/mutex.h>
Catalin Marinas8ad68bb2005-10-31 14:25:02 +000018
19#include <asm/semaphore.h>
Catalin Marinas8ad68bb2005-10-31 14:25:02 +000020#include <asm/hardware/icst307.h>
21
22#include "clock.h"
23
24static LIST_HEAD(clocks);
Arjan van de Ven00431702006-01-12 18:42:23 +000025static DEFINE_MUTEX(clocks_mutex);
Catalin Marinas8ad68bb2005-10-31 14:25:02 +000026
27struct clk *clk_get(struct device *dev, const char *id)
28{
29 struct clk *p, *clk = ERR_PTR(-ENOENT);
30
Arjan van de Ven00431702006-01-12 18:42:23 +000031 mutex_lock(&clocks_mutex);
Catalin Marinas8ad68bb2005-10-31 14:25:02 +000032 list_for_each_entry(p, &clocks, node) {
33 if (strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
34 clk = p;
35 break;
36 }
37 }
Arjan van de Ven00431702006-01-12 18:42:23 +000038 mutex_unlock(&clocks_mutex);
Catalin Marinas8ad68bb2005-10-31 14:25:02 +000039
40 return clk;
41}
42EXPORT_SYMBOL(clk_get);
43
44void clk_put(struct clk *clk)
45{
46 module_put(clk->owner);
47}
48EXPORT_SYMBOL(clk_put);
49
50int clk_enable(struct clk *clk)
51{
52 return 0;
53}
54EXPORT_SYMBOL(clk_enable);
55
56void clk_disable(struct clk *clk)
57{
58}
59EXPORT_SYMBOL(clk_disable);
60
Catalin Marinas8ad68bb2005-10-31 14:25:02 +000061unsigned long clk_get_rate(struct clk *clk)
62{
63 return clk->rate;
64}
65EXPORT_SYMBOL(clk_get_rate);
66
67long clk_round_rate(struct clk *clk, unsigned long rate)
68{
69 return rate;
70}
71EXPORT_SYMBOL(clk_round_rate);
72
73int clk_set_rate(struct clk *clk, unsigned long rate)
74{
75 int ret = -EIO;
76
77 if (clk->setvco) {
78 struct icst307_vco vco;
79
80 vco = icst307_khz_to_vco(clk->params, rate / 1000);
81 clk->rate = icst307_khz(clk->params, vco) * 1000;
82
83 printk("Clock %s: setting VCO reg params: S=%d R=%d V=%d\n",
84 clk->name, vco.s, vco.r, vco.v);
85
86 clk->setvco(clk, vco);
87 ret = 0;
88 }
89 return ret;
90}
91EXPORT_SYMBOL(clk_set_rate);
92
93/*
94 * These are fixed clocks.
95 */
96static struct clk kmi_clk = {
97 .name = "KMIREFCLK",
98 .rate = 24000000,
99};
100
101static struct clk uart_clk = {
102 .name = "UARTCLK",
103 .rate = 24000000,
104};
105
106static struct clk mmci_clk = {
107 .name = "MCLK",
108 .rate = 33000000,
109};
110
111int clk_register(struct clk *clk)
112{
Arjan van de Ven00431702006-01-12 18:42:23 +0000113 mutex_lock(&clocks_mutex);
Catalin Marinas8ad68bb2005-10-31 14:25:02 +0000114 list_add(&clk->node, &clocks);
Arjan van de Ven00431702006-01-12 18:42:23 +0000115 mutex_unlock(&clocks_mutex);
Catalin Marinas8ad68bb2005-10-31 14:25:02 +0000116 return 0;
117}
118EXPORT_SYMBOL(clk_register);
119
120void clk_unregister(struct clk *clk)
121{
Arjan van de Ven00431702006-01-12 18:42:23 +0000122 mutex_lock(&clocks_mutex);
Catalin Marinas8ad68bb2005-10-31 14:25:02 +0000123 list_del(&clk->node);
Arjan van de Ven00431702006-01-12 18:42:23 +0000124 mutex_unlock(&clocks_mutex);
Catalin Marinas8ad68bb2005-10-31 14:25:02 +0000125}
126EXPORT_SYMBOL(clk_unregister);
127
128static int __init clk_init(void)
129{
130 clk_register(&kmi_clk);
131 clk_register(&uart_clk);
132 clk_register(&mmci_clk);
133 return 0;
134}
135arch_initcall(clk_init);