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-rw-r--r--arch/arm/mach-pxa/clock.c124
1 files changed, 124 insertions, 0 deletions
diff --git a/arch/arm/mach-pxa/clock.c b/arch/arm/mach-pxa/clock.c
new file mode 100644
index 000000000000..8f7c90a0593b
--- /dev/null
+++ b/arch/arm/mach-pxa/clock.c
@@ -0,0 +1,124 @@
1/*
2 * linux/arch/arm/mach-sa1100/clock.c
3 */
4#include <linux/module.h>
5#include <linux/kernel.h>
6#include <linux/list.h>
7#include <linux/errno.h>
8#include <linux/err.h>
9#include <linux/string.h>
10#include <linux/clk.h>
11#include <linux/spinlock.h>
12
13#include <asm/arch/pxa-regs.h>
14#include <asm/hardware.h>
15#include <asm/semaphore.h>
16
17struct clk {
18 struct list_head node;
19 unsigned long rate;
20 struct module *owner;
21 const char *name;
22 unsigned int enabled;
23 void (*enable)(void);
24 void (*disable)(void);
25};
26
27static LIST_HEAD(clocks);
28static DECLARE_MUTEX(clocks_sem);
29static DEFINE_SPINLOCK(clocks_lock);
30
31struct clk *clk_get(struct device *dev, const char *id)
32{
33 struct clk *p, *clk = ERR_PTR(-ENOENT);
34
35 down(&clocks_sem);
36 list_for_each_entry(p, &clocks, node) {
37 if (strcmp(id, p->name) == 0 && try_module_get(p->owner)) {
38 clk = p;
39 break;
40 }
41 }
42 up(&clocks_sem);
43
44 return clk;
45}
46EXPORT_SYMBOL(clk_get);
47
48void clk_put(struct clk *clk)
49{
50 module_put(clk->owner);
51}
52EXPORT_SYMBOL(clk_put);
53
54int clk_enable(struct clk *clk)
55{
56 unsigned long flags;
57
58 spin_lock_irqsave(&clocks_lock, flags);
59 if (clk->enabled++ == 0)
60 clk->enable();
61 spin_unlock_irqrestore(&clocks_lock, flags);
62 return 0;
63}
64EXPORT_SYMBOL(clk_enable);
65
66void clk_disable(struct clk *clk)
67{
68 unsigned long flags;
69
70 WARN_ON(clk->enabled == 0);
71
72 spin_lock_irqsave(&clocks_lock, flags);
73 if (--clk->enabled == 0)
74 clk->disable();
75 spin_unlock_irqrestore(&clocks_lock, flags);
76}
77EXPORT_SYMBOL(clk_disable);
78
79unsigned long clk_get_rate(struct clk *clk)
80{
81 return clk->rate;
82}
83EXPORT_SYMBOL(clk_get_rate);
84
85
86static void clk_gpio27_enable(void)
87{
88 pxa_gpio_mode(GPIO11_3_6MHz_MD);
89}
90
91static void clk_gpio27_disable(void)
92{
93}
94
95static struct clk clk_gpio27 = {
96 .name = "GPIO27_CLK",
97 .rate = 3686400,
98 .enable = clk_gpio27_enable,
99 .disable = clk_gpio27_disable,
100};
101
102int clk_register(struct clk *clk)
103{
104 down(&clocks_sem);
105 list_add(&clk->node, &clocks);
106 up(&clocks_sem);
107 return 0;
108}
109EXPORT_SYMBOL(clk_register);
110
111void clk_unregister(struct clk *clk)
112{
113 down(&clocks_sem);
114 list_del(&clk->node);
115 up(&clocks_sem);
116}
117EXPORT_SYMBOL(clk_unregister);
118
119static int __init clk_init(void)
120{
121 clk_register(&clk_gpio27);
122 return 0;
123}
124arch_initcall(clk_init);