Commit | Line | Data |
---|---|---|
97d654f8 RK |
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); |