1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Greybus operations
4 *
5 * Copyright 2015-2016 Google Inc.
6 */
7
8 #include <linux/string.h>
9 #include <linux/sysfs.h>
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/spinlock.h>
13 #include <linux/idr.h>
14
15 #include "audio_manager.h"
16 #include "audio_manager_private.h"
17
18 static struct kset *manager_kset;
19
20 static LIST_HEAD(modules_list);
21 static DECLARE_RWSEM(modules_rwsem);
22 static DEFINE_IDA(module_id);
23
24 /* helpers */
gb_audio_manager_get_locked(int id)25 static struct gb_audio_manager_module *gb_audio_manager_get_locked(int id)
26 {
27 struct gb_audio_manager_module *module;
28
29 if (id < 0)
30 return NULL;
31
32 list_for_each_entry(module, &modules_list, list) {
33 if (module->id == id)
34 return module;
35 }
36
37 return NULL;
38 }
39
40 /* public API */
gb_audio_manager_add(struct gb_audio_manager_module_descriptor * desc)41 int gb_audio_manager_add(struct gb_audio_manager_module_descriptor *desc)
42 {
43 struct gb_audio_manager_module *module;
44 int id;
45 int err;
46
47 id = ida_simple_get(&module_id, 0, 0, GFP_KERNEL);
48 err = gb_audio_manager_module_create(&module, manager_kset,
49 id, desc);
50 if (err) {
51 ida_simple_remove(&module_id, id);
52 return err;
53 }
54
55 /* Add it to the list */
56 down_write(&modules_rwsem);
57 list_add_tail(&module->list, &modules_list);
58 up_write(&modules_rwsem);
59
60 return module->id;
61 }
62 EXPORT_SYMBOL_GPL(gb_audio_manager_add);
63
gb_audio_manager_remove(int id)64 int gb_audio_manager_remove(int id)
65 {
66 struct gb_audio_manager_module *module;
67
68 down_write(&modules_rwsem);
69
70 module = gb_audio_manager_get_locked(id);
71 if (!module) {
72 up_write(&modules_rwsem);
73 return -EINVAL;
74 }
75 list_del(&module->list);
76 kobject_put(&module->kobj);
77 up_write(&modules_rwsem);
78 ida_simple_remove(&module_id, id);
79 return 0;
80 }
81 EXPORT_SYMBOL_GPL(gb_audio_manager_remove);
82
gb_audio_manager_remove_all(void)83 void gb_audio_manager_remove_all(void)
84 {
85 struct gb_audio_manager_module *module, *next;
86 int is_empty = 1;
87
88 down_write(&modules_rwsem);
89
90 list_for_each_entry_safe(module, next, &modules_list, list) {
91 list_del(&module->list);
92 kobject_put(&module->kobj);
93 ida_simple_remove(&module_id, module->id);
94 }
95
96 is_empty = list_empty(&modules_list);
97
98 up_write(&modules_rwsem);
99
100 if (!is_empty)
101 pr_warn("Not all nodes were deleted\n");
102 }
103 EXPORT_SYMBOL_GPL(gb_audio_manager_remove_all);
104
gb_audio_manager_get_module(int id)105 struct gb_audio_manager_module *gb_audio_manager_get_module(int id)
106 {
107 struct gb_audio_manager_module *module;
108
109 down_read(&modules_rwsem);
110 module = gb_audio_manager_get_locked(id);
111 kobject_get(&module->kobj);
112 up_read(&modules_rwsem);
113 return module;
114 }
115 EXPORT_SYMBOL_GPL(gb_audio_manager_get_module);
116
gb_audio_manager_put_module(struct gb_audio_manager_module * module)117 void gb_audio_manager_put_module(struct gb_audio_manager_module *module)
118 {
119 kobject_put(&module->kobj);
120 }
121 EXPORT_SYMBOL_GPL(gb_audio_manager_put_module);
122
gb_audio_manager_dump_module(int id)123 int gb_audio_manager_dump_module(int id)
124 {
125 struct gb_audio_manager_module *module;
126
127 down_read(&modules_rwsem);
128 module = gb_audio_manager_get_locked(id);
129 up_read(&modules_rwsem);
130
131 if (!module)
132 return -EINVAL;
133
134 gb_audio_manager_module_dump(module);
135 return 0;
136 }
137 EXPORT_SYMBOL_GPL(gb_audio_manager_dump_module);
138
gb_audio_manager_dump_all(void)139 void gb_audio_manager_dump_all(void)
140 {
141 struct gb_audio_manager_module *module;
142 int count = 0;
143
144 down_read(&modules_rwsem);
145 list_for_each_entry(module, &modules_list, list) {
146 gb_audio_manager_module_dump(module);
147 count++;
148 }
149 up_read(&modules_rwsem);
150
151 pr_info("Number of connected modules: %d\n", count);
152 }
153 EXPORT_SYMBOL_GPL(gb_audio_manager_dump_all);
154
155 /*
156 * module init/deinit
157 */
manager_init(void)158 static int __init manager_init(void)
159 {
160 manager_kset = kset_create_and_add(GB_AUDIO_MANAGER_NAME, NULL,
161 kernel_kobj);
162 if (!manager_kset)
163 return -ENOMEM;
164
165 #ifdef GB_AUDIO_MANAGER_SYSFS
166 gb_audio_manager_sysfs_init(&manager_kset->kobj);
167 #endif
168
169 return 0;
170 }
171
manager_exit(void)172 static void __exit manager_exit(void)
173 {
174 gb_audio_manager_remove_all();
175 kset_unregister(manager_kset);
176 ida_destroy(&module_id);
177 }
178
179 module_init(manager_init);
180 module_exit(manager_exit);
181
182 MODULE_LICENSE("GPL");
183 MODULE_AUTHOR("Svetlin Ankov <ankov_svetlin@projectara.com>");
184
