Linux-2.6.12-rc2
[linux-2.6.git] / arch / arm / mach-integrator / clock.c
1 /*
2  *  linux/arch/arm/mach-integrator/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>
16
17 #include <asm/semaphore.h>
18 #include <asm/hardware/clock.h>
19 #include <asm/hardware/icst525.h>
20
21 #include "clock.h"
22
23 static LIST_HEAD(clocks);
24 static DECLARE_MUTEX(clocks_sem);
25
26 struct clk *clk_get(struct device *dev, const char *id)
27 {
28         struct clk *p, *clk = ERR_PTR(-ENOENT);
29
30         down(&clocks_sem);
31         list_for_each_entry(p, &clocks, node) {
32                 if (strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
33                         clk = p;
34                         break;
35                 }
36         }
37         up(&clocks_sem);
38
39         return clk;
40 }
41 EXPORT_SYMBOL(clk_get);
42
43 void clk_put(struct clk *clk)
44 {
45         module_put(clk->owner);
46 }
47 EXPORT_SYMBOL(clk_put);
48
49 int clk_enable(struct clk *clk)
50 {
51         return 0;
52 }
53 EXPORT_SYMBOL(clk_enable);
54
55 void clk_disable(struct clk *clk)
56 {
57 }
58 EXPORT_SYMBOL(clk_disable);
59
60 int clk_use(struct clk *clk)
61 {
62         return 0;
63 }
64 EXPORT_SYMBOL(clk_use);
65
66 void clk_unuse(struct clk *clk)
67 {
68 }
69 EXPORT_SYMBOL(clk_unuse);
70
71 unsigned long clk_get_rate(struct clk *clk)
72 {
73         return clk->rate;
74 }
75 EXPORT_SYMBOL(clk_get_rate);
76
77 long clk_round_rate(struct clk *clk, unsigned long rate)
78 {
79         struct icst525_vco vco;
80
81         vco = icst525_khz_to_vco(clk->params, rate / 1000);
82         return icst525_khz(clk->params, vco) * 1000;
83 }
84 EXPORT_SYMBOL(clk_round_rate);
85
86 int clk_set_rate(struct clk *clk, unsigned long rate)
87 {
88         int ret = -EIO;
89         if (clk->setvco) {
90                 struct icst525_vco vco;
91
92                 vco = icst525_khz_to_vco(clk->params, rate / 1000);
93                 clk->rate = icst525_khz(clk->params, vco) * 1000;
94
95                 printk("Clock %s: setting VCO reg params: S=%d R=%d V=%d\n",
96                         clk->name, vco.s, vco.r, vco.v);
97
98                 clk->setvco(clk, vco);
99                 ret = 0;
100         }
101         return 0;
102 }
103 EXPORT_SYMBOL(clk_set_rate);
104
105 /*
106  * These are fixed clocks.
107  */
108 static struct clk kmi_clk = {
109         .name   = "KMIREFCLK",
110         .rate   = 24000000,
111 };
112
113 static struct clk uart_clk = {
114         .name   = "UARTCLK",
115         .rate   = 14745600,
116 };
117
118 int clk_register(struct clk *clk)
119 {
120         down(&clocks_sem);
121         list_add(&clk->node, &clocks);
122         up(&clocks_sem);
123         return 0;
124 }
125 EXPORT_SYMBOL(clk_register);
126
127 void clk_unregister(struct clk *clk)
128 {
129         down(&clocks_sem);
130         list_del(&clk->node);
131         up(&clocks_sem);
132 }
133 EXPORT_SYMBOL(clk_unregister);
134
135 static int __init clk_init(void)
136 {
137         clk_register(&kmi_clk);
138         clk_register(&uart_clk);
139         return 0;
140 }
141 arch_initcall(clk_init);