tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * linux/arch/arm/mach-versatile/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#include <linux/string.h>
17#include <linux/clk.h>
18#include <linux/mutex.h>
19
20#include <asm/semaphore.h>
21#include <asm/hardware/icst307.h>
22
23#include "clock.h"
24
25static LIST_HEAD(clocks);
26static DEFINE_MUTEX(clocks_mutex);
27
28struct clk *clk_get(struct device *dev, const char *id)
29{
30 struct clk *p, *clk = ERR_PTR(-ENOENT);
31
32 mutex_lock(&clocks_mutex);
33 list_for_each_entry(p, &clocks, node) {
34 if (strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
35 clk = p;
36 break;
37 }
38 }
39 mutex_unlock(&clocks_mutex);
40
41 return clk;
42}
43EXPORT_SYMBOL(clk_get);
44
45void clk_put(struct clk *clk)
46{
47 module_put(clk->owner);
48}
49EXPORT_SYMBOL(clk_put);
50
51int clk_enable(struct clk *clk)
52{
53 return 0;
54}
55EXPORT_SYMBOL(clk_enable);
56
57void clk_disable(struct clk *clk)
58{
59}
60EXPORT_SYMBOL(clk_disable);
61
62unsigned long clk_get_rate(struct clk *clk)
63{
64 return clk->rate;
65}
66EXPORT_SYMBOL(clk_get_rate);
67
68long clk_round_rate(struct clk *clk, unsigned long rate)
69{
70 return rate;
71}
72EXPORT_SYMBOL(clk_round_rate);
73
74int clk_set_rate(struct clk *clk, unsigned long rate)
75{
76 int ret = -EIO;
77
78 if (clk->setvco) {
79 struct icst307_vco vco;
80
81 vco = icst307_khz_to_vco(clk->params, rate / 1000);
82 clk->rate = icst307_khz(clk->params, vco) * 1000;
83
84 printk("Clock %s: setting VCO reg params: S=%d R=%d V=%d\n",
85 clk->name, vco.s, vco.r, vco.v);
86
87 clk->setvco(clk, vco);
88 ret = 0;
89 }
90 return ret;
91}
92EXPORT_SYMBOL(clk_set_rate);
93
94/*
95 * These are fixed clocks.
96 */
97static struct clk kmi_clk = {
98 .name = "KMIREFCLK",
99 .rate = 24000000,
100};
101
102static struct clk uart_clk = {
103 .name = "UARTCLK",
104 .rate = 24000000,
105};
106
107static struct clk mmci_clk = {
108 .name = "MCLK",
109 .rate = 33000000,
110};
111
112int clk_register(struct clk *clk)
113{
114 mutex_lock(&clocks_mutex);
115 list_add(&clk->node, &clocks);
116 mutex_unlock(&clocks_mutex);
117 return 0;
118}
119EXPORT_SYMBOL(clk_register);
120
121void clk_unregister(struct clk *clk)
122{
123 mutex_lock(&clocks_mutex);
124 list_del(&clk->node);
125 mutex_unlock(&clocks_mutex);
126}
127EXPORT_SYMBOL(clk_unregister);
128
129static int __init clk_init(void)
130{
131 clk_register(&kmi_clk);
132 clk_register(&uart_clk);
133 clk_register(&mmci_clk);
134 return 0;
135}
136arch_initcall(clk_init);