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#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 device *cd;
static int req_count;
cd = device_create(dca_class, dca->cd, MKDEV(0, slot + 1), NULL,
"requester%d", req_count++);
if (IS_ERR(cd))
return PTR_ERR(cd);
return 0;
}
void dca_sysfs_remove_req(struct dca_provider *dca, int slot)
{
device_destroy(dca_class, MKDEV(0, slot + 1));
}
int dca_sysfs_add_provider(struct dca_provider *dca, struct device *dev)
{
struct 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 = device_create(dca_class, dev, MKDEV(0, 0), NULL, "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)
{
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);
}
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