1 /* 2 * Copyright(c) 2015, 2016 Intel Corporation. 3 * 4 * This file is provided under a dual BSD/GPLv2 license. When using or 5 * redistributing this file, you may do so under either license. 6 * 7 * GPL LICENSE SUMMARY 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of version 2 of the GNU General Public License as 11 * published by the Free Software Foundation. 12 * 13 * This program is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * 18 * BSD LICENSE 19 * 20 * Redistribution and use in source and binary forms, with or without 21 * modification, are permitted provided that the following conditions 22 * are met: 23 * 24 * - Redistributions of source code must retain the above copyright 25 * notice, this list of conditions and the following disclaimer. 26 * - Redistributions in binary form must reproduce the above copyright 27 * notice, this list of conditions and the following disclaimer in 28 * the documentation and/or other materials provided with the 29 * distribution. 30 * - Neither the name of Intel Corporation nor the names of its 31 * contributors may be used to endorse or promote products derived 32 * from this software without specific prior written permission. 33 * 34 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 35 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 36 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 37 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 38 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 39 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 40 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 41 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 42 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 43 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 44 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 45 * 46 */ 47 48 #include <linux/cdev.h> 49 #include <linux/module.h> 50 #include <linux/device.h> 51 #include <linux/fs.h> 52 53 #include "hfi.h" 54 #include "device.h" 55 56 static struct class *class; 57 static struct class *user_class; 58 static dev_t hfi1_dev; 59 60 int hfi1_cdev_init(int minor, const char *name, 61 const struct file_operations *fops, 62 struct cdev *cdev, struct device **devp, 63 bool user_accessible, 64 struct kobject *parent) 65 { 66 const dev_t dev = MKDEV(MAJOR(hfi1_dev), minor); 67 struct device *device = NULL; 68 int ret; 69 70 cdev_init(cdev, fops); 71 cdev->owner = THIS_MODULE; 72 cdev->kobj.parent = parent; 73 kobject_set_name(&cdev->kobj, name); 74 75 ret = cdev_add(cdev, dev, 1); 76 if (ret < 0) { 77 pr_err("Could not add cdev for minor %d, %s (err %d)\n", 78 minor, name, -ret); 79 goto done; 80 } 81 82 if (user_accessible) 83 device = device_create(user_class, NULL, dev, NULL, "%s", name); 84 else 85 device = device_create(class, NULL, dev, NULL, "%s", name); 86 87 if (IS_ERR(device)) { 88 ret = PTR_ERR(device); 89 device = NULL; 90 pr_err("Could not create device for minor %d, %s (err %d)\n", 91 minor, name, -ret); 92 cdev_del(cdev); 93 } 94 done: 95 *devp = device; 96 return ret; 97 } 98 99 void hfi1_cdev_cleanup(struct cdev *cdev, struct device **devp) 100 { 101 struct device *device = *devp; 102 103 if (device) { 104 device_unregister(device); 105 *devp = NULL; 106 107 cdev_del(cdev); 108 } 109 } 110 111 static const char *hfi1_class_name = "hfi1"; 112 113 const char *class_name(void) 114 { 115 return hfi1_class_name; 116 } 117 118 static char *hfi1_devnode(struct device *dev, umode_t *mode) 119 { 120 if (mode) 121 *mode = 0600; 122 return kasprintf(GFP_KERNEL, "%s", dev_name(dev)); 123 } 124 125 static const char *hfi1_class_name_user = "hfi1_user"; 126 static const char *class_name_user(void) 127 { 128 return hfi1_class_name_user; 129 } 130 131 static char *hfi1_user_devnode(struct device *dev, umode_t *mode) 132 { 133 if (mode) 134 *mode = 0666; 135 return kasprintf(GFP_KERNEL, "%s", dev_name(dev)); 136 } 137 138 int __init dev_init(void) 139 { 140 int ret; 141 142 ret = alloc_chrdev_region(&hfi1_dev, 0, HFI1_NMINORS, DRIVER_NAME); 143 if (ret < 0) { 144 pr_err("Could not allocate chrdev region (err %d)\n", -ret); 145 goto done; 146 } 147 148 class = class_create(THIS_MODULE, class_name()); 149 if (IS_ERR(class)) { 150 ret = PTR_ERR(class); 151 pr_err("Could not create device class (err %d)\n", -ret); 152 unregister_chrdev_region(hfi1_dev, HFI1_NMINORS); 153 goto done; 154 } 155 class->devnode = hfi1_devnode; 156 157 user_class = class_create(THIS_MODULE, class_name_user()); 158 if (IS_ERR(user_class)) { 159 ret = PTR_ERR(user_class); 160 pr_err("Could not create device class for user accessible files (err %d)\n", 161 -ret); 162 class_destroy(class); 163 class = NULL; 164 user_class = NULL; 165 unregister_chrdev_region(hfi1_dev, HFI1_NMINORS); 166 goto done; 167 } 168 user_class->devnode = hfi1_user_devnode; 169 170 done: 171 return ret; 172 } 173 174 void dev_cleanup(void) 175 { 176 class_destroy(class); 177 class = NULL; 178 179 class_destroy(user_class); 180 user_class = NULL; 181 182 unregister_chrdev_region(hfi1_dev, HFI1_NMINORS); 183 } 184