diff options
Diffstat (limited to 'arch/arm/mach-pxa/clock.c')
-rw-r--r-- | arch/arm/mach-pxa/clock.c | 124 |
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 | |||
17 | struct 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 | |||
27 | static LIST_HEAD(clocks); | ||
28 | static DECLARE_MUTEX(clocks_sem); | ||
29 | static DEFINE_SPINLOCK(clocks_lock); | ||
30 | |||
31 | struct 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 | } | ||
46 | EXPORT_SYMBOL(clk_get); | ||
47 | |||
48 | void clk_put(struct clk *clk) | ||
49 | { | ||
50 | module_put(clk->owner); | ||
51 | } | ||
52 | EXPORT_SYMBOL(clk_put); | ||
53 | |||
54 | int 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 | } | ||
64 | EXPORT_SYMBOL(clk_enable); | ||
65 | |||
66 | void 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 | } | ||
77 | EXPORT_SYMBOL(clk_disable); | ||
78 | |||
79 | unsigned long clk_get_rate(struct clk *clk) | ||
80 | { | ||
81 | return clk->rate; | ||
82 | } | ||
83 | EXPORT_SYMBOL(clk_get_rate); | ||
84 | |||
85 | |||
86 | static void clk_gpio27_enable(void) | ||
87 | { | ||
88 | pxa_gpio_mode(GPIO11_3_6MHz_MD); | ||
89 | } | ||
90 | |||
91 | static void clk_gpio27_disable(void) | ||
92 | { | ||
93 | } | ||
94 | |||
95 | static struct clk clk_gpio27 = { | ||
96 | .name = "GPIO27_CLK", | ||
97 | .rate = 3686400, | ||
98 | .enable = clk_gpio27_enable, | ||
99 | .disable = clk_gpio27_disable, | ||
100 | }; | ||
101 | |||
102 | int clk_register(struct clk *clk) | ||
103 | { | ||
104 | down(&clocks_sem); | ||
105 | list_add(&clk->node, &clocks); | ||
106 | up(&clocks_sem); | ||
107 | return 0; | ||
108 | } | ||
109 | EXPORT_SYMBOL(clk_register); | ||
110 | |||
111 | void clk_unregister(struct clk *clk) | ||
112 | { | ||
113 | down(&clocks_sem); | ||
114 | list_del(&clk->node); | ||
115 | up(&clocks_sem); | ||
116 | } | ||
117 | EXPORT_SYMBOL(clk_unregister); | ||
118 | |||
119 | static int __init clk_init(void) | ||
120 | { | ||
121 | clk_register(&clk_gpio27); | ||
122 | return 0; | ||
123 | } | ||
124 | arch_initcall(clk_init); | ||