1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
|
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/device.h>
#include <linux/idr.h>
#include <linux/kdev_t.h>
#include <linux/err.h>
#include <linux/dca.h>
static struct class *dca_class;
static struct idr dca_idr;
static spinlock_t dca_idr_lock;
int dca_sysfs_add_req(struct dca_provider *dca, struct device *dev, int slot)
{
struct class_device *cd;
cd = class_device_create(dca_class, dca->cd, MKDEV(0, slot + 1),
dev, "requester%d", slot);
if (IS_ERR(cd))
return PTR_ERR(cd);
return 0;
}
void dca_sysfs_remove_req(struct dca_provider *dca, int slot)
{
class_device_destroy(dca_class, MKDEV(0, slot + 1));
}
int dca_sysfs_add_provider(struct dca_provider *dca, struct device *dev)
{
struct class_device *cd;
int err = 0;
idr_try_again:
if (!idr_pre_get(&dca_idr, GFP_KERNEL))
return -ENOMEM;
spin_lock(&dca_idr_lock);
err = idr_get_new(&dca_idr, dca, &dca->id);
spin_unlock(&dca_idr_lock);
switch (err) {
case 0:
break;
case -EAGAIN:
goto idr_try_again;
default:
return err;
}
cd = class_device_create(dca_class, NULL, MKDEV(0, 0),
dev, "dca%d", dca->id);
if (IS_ERR(cd)) {
spin_lock(&dca_idr_lock);
idr_remove(&dca_idr, dca->id);
spin_unlock(&dca_idr_lock);
return PTR_ERR(cd);
}
dca->cd = cd;
return 0;
}
void dca_sysfs_remove_provider(struct dca_provider *dca)
{
class_device_unregister(dca->cd);
dca->cd = NULL;
spin_lock(&dca_idr_lock);
idr_remove(&dca_idr, dca->id);
spin_unlock(&dca_idr_lock);
}
int __init dca_sysfs_init(void)
{
idr_init(&dca_idr);
spin_lock_init(&dca_idr_lock);
dca_class = class_create(THIS_MODULE, "dca");
if (IS_ERR(dca_class)) {
idr_destroy(&dca_idr);
return PTR_ERR(dca_class);
}
return 0;
}
void __exit dca_sysfs_exit(void)
{
class_destroy(dca_class);
idr_destroy(&dca_idr);
}
|
