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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved.4 */5 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 const struct class dca_class = {17 .name = "dca",18};19static struct idr dca_idr;20static spinlock_t dca_idr_lock;21 22int dca_sysfs_add_req(struct dca_provider *dca, struct device *dev, int slot)23{24 struct device *cd;25 static int req_count;26 27 cd = device_create(&dca_class, dca->cd, MKDEV(0, slot + 1), NULL,28 "requester%d", req_count++);29 return PTR_ERR_OR_ZERO(cd);30}31 32void dca_sysfs_remove_req(struct dca_provider *dca, int slot)33{34 device_destroy(&dca_class, MKDEV(0, slot + 1));35}36 37int dca_sysfs_add_provider(struct dca_provider *dca, struct device *dev)38{39 struct device *cd;40 int ret;41 42 idr_preload(GFP_KERNEL);43 spin_lock(&dca_idr_lock);44 45 ret = idr_alloc(&dca_idr, dca, 0, 0, GFP_NOWAIT);46 if (ret >= 0)47 dca->id = ret;48 49 spin_unlock(&dca_idr_lock);50 idr_preload_end();51 if (ret < 0)52 return ret;53 54 cd = device_create(&dca_class, dev, MKDEV(0, 0), NULL, "dca%d", dca->id);55 if (IS_ERR(cd)) {56 spin_lock(&dca_idr_lock);57 idr_remove(&dca_idr, dca->id);58 spin_unlock(&dca_idr_lock);59 return PTR_ERR(cd);60 }61 dca->cd = cd;62 return 0;63}64 65void dca_sysfs_remove_provider(struct dca_provider *dca)66{67 device_unregister(dca->cd);68 dca->cd = NULL;69 spin_lock(&dca_idr_lock);70 idr_remove(&dca_idr, dca->id);71 spin_unlock(&dca_idr_lock);72}73 74int __init dca_sysfs_init(void)75{76 int err;77 78 idr_init(&dca_idr);79 spin_lock_init(&dca_idr_lock);80 81 err = class_register(&dca_class);82 if (err) {83 idr_destroy(&dca_idr);84 return err;85 }86 return 0;87}88 89void __exit dca_sysfs_exit(void)90{91 class_unregister(&dca_class);92 idr_destroy(&dca_idr);93}94 95