diff options
Diffstat (limited to 'drivers/misc/atmel_tclib.c')
-rw-r--r-- | drivers/misc/atmel_tclib.c | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/drivers/misc/atmel_tclib.c b/drivers/misc/atmel_tclib.c new file mode 100644 index 000000000000..05dc8a31f280 --- /dev/null +++ b/drivers/misc/atmel_tclib.c | |||
@@ -0,0 +1,161 @@ | |||
1 | #include <linux/atmel_tc.h> | ||
2 | #include <linux/clk.h> | ||
3 | #include <linux/err.h> | ||
4 | #include <linux/init.h> | ||
5 | #include <linux/io.h> | ||
6 | #include <linux/ioport.h> | ||
7 | #include <linux/kernel.h> | ||
8 | #include <linux/platform_device.h> | ||
9 | |||
10 | /* Number of bytes to reserve for the iomem resource */ | ||
11 | #define ATMEL_TC_IOMEM_SIZE 256 | ||
12 | |||
13 | |||
14 | /* | ||
15 | * This is a thin library to solve the problem of how to portably allocate | ||
16 | * one of the TC blocks. For simplicity, it doesn't currently expect to | ||
17 | * share individual timers between different drivers. | ||
18 | */ | ||
19 | |||
20 | #if defined(CONFIG_AVR32) | ||
21 | /* AVR32 has these divide PBB */ | ||
22 | const u8 atmel_tc_divisors[5] = { 0, 4, 8, 16, 32, }; | ||
23 | EXPORT_SYMBOL(atmel_tc_divisors); | ||
24 | |||
25 | #elif defined(CONFIG_ARCH_AT91) | ||
26 | /* AT91 has these divide MCK */ | ||
27 | const u8 atmel_tc_divisors[5] = { 2, 8, 32, 128, 0, }; | ||
28 | EXPORT_SYMBOL(atmel_tc_divisors); | ||
29 | |||
30 | #endif | ||
31 | |||
32 | static DEFINE_SPINLOCK(tc_list_lock); | ||
33 | static LIST_HEAD(tc_list); | ||
34 | |||
35 | /** | ||
36 | * atmel_tc_alloc - allocate a specified TC block | ||
37 | * @block: which block to allocate | ||
38 | * @name: name to be associated with the iomem resource | ||
39 | * | ||
40 | * Caller allocates a block. If it is available, a pointer to a | ||
41 | * pre-initialized struct atmel_tc is returned. The caller can access | ||
42 | * the registers directly through the "regs" field. | ||
43 | */ | ||
44 | struct atmel_tc *atmel_tc_alloc(unsigned block, const char *name) | ||
45 | { | ||
46 | struct atmel_tc *tc; | ||
47 | struct platform_device *pdev = NULL; | ||
48 | struct resource *r; | ||
49 | |||
50 | spin_lock(&tc_list_lock); | ||
51 | list_for_each_entry(tc, &tc_list, node) { | ||
52 | if (tc->pdev->id == block) { | ||
53 | pdev = tc->pdev; | ||
54 | break; | ||
55 | } | ||
56 | } | ||
57 | |||
58 | if (!pdev || tc->iomem) | ||
59 | goto fail; | ||
60 | |||
61 | r = platform_get_resource(pdev, IORESOURCE_MEM, 0); | ||
62 | r = request_mem_region(r->start, ATMEL_TC_IOMEM_SIZE, name); | ||
63 | if (!r) | ||
64 | goto fail; | ||
65 | |||
66 | tc->regs = ioremap(r->start, ATMEL_TC_IOMEM_SIZE); | ||
67 | if (!tc->regs) | ||
68 | goto fail_ioremap; | ||
69 | |||
70 | tc->iomem = r; | ||
71 | |||
72 | out: | ||
73 | spin_unlock(&tc_list_lock); | ||
74 | return tc; | ||
75 | |||
76 | fail_ioremap: | ||
77 | release_resource(r); | ||
78 | fail: | ||
79 | tc = NULL; | ||
80 | goto out; | ||
81 | } | ||
82 | EXPORT_SYMBOL_GPL(atmel_tc_alloc); | ||
83 | |||
84 | /** | ||
85 | * atmel_tc_free - release a specified TC block | ||
86 | * @tc: Timer/counter block that was returned by atmel_tc_alloc() | ||
87 | * | ||
88 | * This reverses the effect of atmel_tc_alloc(), unmapping the I/O | ||
89 | * registers, invalidating the resource returned by that routine and | ||
90 | * making the TC available to other drivers. | ||
91 | */ | ||
92 | void atmel_tc_free(struct atmel_tc *tc) | ||
93 | { | ||
94 | spin_lock(&tc_list_lock); | ||
95 | if (tc->regs) { | ||
96 | iounmap(tc->regs); | ||
97 | release_resource(tc->iomem); | ||
98 | tc->regs = NULL; | ||
99 | tc->iomem = NULL; | ||
100 | } | ||
101 | spin_unlock(&tc_list_lock); | ||
102 | } | ||
103 | EXPORT_SYMBOL_GPL(atmel_tc_free); | ||
104 | |||
105 | static int __init tc_probe(struct platform_device *pdev) | ||
106 | { | ||
107 | struct atmel_tc *tc; | ||
108 | struct clk *clk; | ||
109 | int irq; | ||
110 | |||
111 | if (!platform_get_resource(pdev, IORESOURCE_MEM, 0)) | ||
112 | return -EINVAL; | ||
113 | |||
114 | irq = platform_get_irq(pdev, 0); | ||
115 | if (irq < 0) | ||
116 | return -EINVAL; | ||
117 | |||
118 | tc = kzalloc(sizeof(struct atmel_tc), GFP_KERNEL); | ||
119 | if (!tc) | ||
120 | return -ENOMEM; | ||
121 | |||
122 | tc->pdev = pdev; | ||
123 | |||
124 | clk = clk_get(&pdev->dev, "t0_clk"); | ||
125 | if (IS_ERR(clk)) { | ||
126 | kfree(tc); | ||
127 | return -EINVAL; | ||
128 | } | ||
129 | |||
130 | tc->clk[0] = clk; | ||
131 | tc->clk[1] = clk_get(&pdev->dev, "t1_clk"); | ||
132 | if (IS_ERR(tc->clk[1])) | ||
133 | tc->clk[1] = clk; | ||
134 | tc->clk[2] = clk_get(&pdev->dev, "t2_clk"); | ||
135 | if (IS_ERR(tc->clk[2])) | ||
136 | tc->clk[2] = clk; | ||
137 | |||
138 | tc->irq[0] = irq; | ||
139 | tc->irq[1] = platform_get_irq(pdev, 1); | ||
140 | if (tc->irq[1] < 0) | ||
141 | tc->irq[1] = irq; | ||
142 | tc->irq[2] = platform_get_irq(pdev, 2); | ||
143 | if (tc->irq[2] < 0) | ||
144 | tc->irq[2] = irq; | ||
145 | |||
146 | spin_lock(&tc_list_lock); | ||
147 | list_add_tail(&tc->node, &tc_list); | ||
148 | spin_unlock(&tc_list_lock); | ||
149 | |||
150 | return 0; | ||
151 | } | ||
152 | |||
153 | static struct platform_driver tc_driver = { | ||
154 | .driver.name = "atmel_tcb", | ||
155 | }; | ||
156 | |||
157 | static int __init tc_init(void) | ||
158 | { | ||
159 | return platform_driver_probe(&tc_driver, tc_probe); | ||
160 | } | ||
161 | arch_initcall(tc_init); | ||