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6#include <linux/kernel.h>
7#include <linux/spinlock.h>
8#include <linux/device.h>
9#include <linux/idr.h>
10#include <linux/kdev_t.h>
11#include <linux/err.h>
12#include <linux/dca.h>
13#include <linux/gfp.h>
14#include <linux/export.h>
15
16static struct class *dca_class;
17static struct idr dca_idr;
18static spinlock_t dca_idr_lock;
19
20int dca_sysfs_add_req(struct dca_provider *dca, struct device *dev, int slot)
21{
22 struct device *cd;
23 static int req_count;
24
25 cd = device_create(dca_class, dca->cd, MKDEV(0, slot + 1), NULL,
26 "requester%d", req_count++);
27 return PTR_ERR_OR_ZERO(cd);
28}
29
30void dca_sysfs_remove_req(struct dca_provider *dca, int slot)
31{
32 device_destroy(dca_class, MKDEV(0, slot + 1));
33}
34
35int dca_sysfs_add_provider(struct dca_provider *dca, struct device *dev)
36{
37 struct device *cd;
38 int ret;
39
40 idr_preload(GFP_KERNEL);
41 spin_lock(&dca_idr_lock);
42
43 ret = idr_alloc(&dca_idr, dca, 0, 0, GFP_NOWAIT);
44 if (ret >= 0)
45 dca->id = ret;
46
47 spin_unlock(&dca_idr_lock);
48 idr_preload_end();
49 if (ret < 0)
50 return ret;
51
52 cd = device_create(dca_class, dev, MKDEV(0, 0), NULL, "dca%d", dca->id);
53 if (IS_ERR(cd)) {
54 spin_lock(&dca_idr_lock);
55 idr_remove(&dca_idr, dca->id);
56 spin_unlock(&dca_idr_lock);
57 return PTR_ERR(cd);
58 }
59 dca->cd = cd;
60 return 0;
61}
62
63void dca_sysfs_remove_provider(struct dca_provider *dca)
64{
65 device_unregister(dca->cd);
66 dca->cd = NULL;
67 spin_lock(&dca_idr_lock);
68 idr_remove(&dca_idr, dca->id);
69 spin_unlock(&dca_idr_lock);
70}
71
72int __init dca_sysfs_init(void)
73{
74 idr_init(&dca_idr);
75 spin_lock_init(&dca_idr_lock);
76
77 dca_class = class_create(THIS_MODULE, "dca");
78 if (IS_ERR(dca_class)) {
79 idr_destroy(&dca_idr);
80 return PTR_ERR(dca_class);
81 }
82 return 0;
83}
84
85void __exit dca_sysfs_exit(void)
86{
87 class_destroy(dca_class);
88 idr_destroy(&dca_idr);
89}
90
91
