1 /* 2 * Copyright(c) 2007 - 2009 Intel Corporation. All rights reserved. 3 * 4 * This program is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License as published by the Free 6 * Software Foundation; either version 2 of the License, or (at your option) 7 * any later version. 8 * 9 * This program is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 * 14 * You should have received a copy of the GNU General Public License along with 15 * this program; if not, write to the Free Software Foundation, Inc., 59 16 * Temple Place - Suite 330, Boston, MA 02111-1307, USA. 17 * 18 * The full GNU General Public License is included in this distribution in the 19 * file called COPYING. 20 */ 21 22 #include <linux/kernel.h> 23 #include <linux/spinlock.h> 24 #include <linux/device.h> 25 #include <linux/idr.h> 26 #include <linux/kdev_t.h> 27 #include <linux/err.h> 28 #include <linux/dca.h> 29 #include <linux/gfp.h> 30 #include <linux/export.h> 31 32 static struct class *dca_class; 33 static struct idr dca_idr; 34 static spinlock_t dca_idr_lock; 35 36 int dca_sysfs_add_req(struct dca_provider *dca, struct device *dev, int slot) 37 { 38 struct device *cd; 39 static int req_count; 40 41 cd = device_create(dca_class, dca->cd, MKDEV(0, slot + 1), NULL, 42 "requester%d", req_count++); 43 if (IS_ERR(cd)) 44 return PTR_ERR(cd); 45 return 0; 46 } 47 48 void dca_sysfs_remove_req(struct dca_provider *dca, int slot) 49 { 50 device_destroy(dca_class, MKDEV(0, slot + 1)); 51 } 52 53 int dca_sysfs_add_provider(struct dca_provider *dca, struct device *dev) 54 { 55 struct device *cd; 56 int ret; 57 58 idr_preload(GFP_KERNEL); 59 spin_lock(&dca_idr_lock); 60 61 ret = idr_alloc(&dca_idr, dca, 0, 0, GFP_NOWAIT); 62 if (ret >= 0) 63 dca->id = ret; 64 65 spin_unlock(&dca_idr_lock); 66 idr_preload_end(); 67 if (ret < 0) 68 return ret; 69 70 cd = device_create(dca_class, dev, MKDEV(0, 0), NULL, "dca%d", dca->id); 71 if (IS_ERR(cd)) { 72 spin_lock(&dca_idr_lock); 73 idr_remove(&dca_idr, dca->id); 74 spin_unlock(&dca_idr_lock); 75 return PTR_ERR(cd); 76 } 77 dca->cd = cd; 78 return 0; 79 } 80 81 void dca_sysfs_remove_provider(struct dca_provider *dca) 82 { 83 device_unregister(dca->cd); 84 dca->cd = NULL; 85 spin_lock(&dca_idr_lock); 86 idr_remove(&dca_idr, dca->id); 87 spin_unlock(&dca_idr_lock); 88 } 89 90 int __init dca_sysfs_init(void) 91 { 92 idr_init(&dca_idr); 93 spin_lock_init(&dca_idr_lock); 94 95 dca_class = class_create(THIS_MODULE, "dca"); 96 if (IS_ERR(dca_class)) { 97 idr_destroy(&dca_idr); 98 return PTR_ERR(dca_class); 99 } 100 return 0; 101 } 102 103 void __exit dca_sysfs_exit(void) 104 { 105 class_destroy(dca_class); 106 idr_destroy(&dca_idr); 107 } 108 109