#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; cd = device_create(dca_class, dca->cd, MKDEV(0, slot + 1), "requester%d", slot); 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), "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); }