1/*
2 * ACPI configfs support
3 *
4 * Copyright (c) 2016 Intel Corporation
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published by
8 * the Free Software Foundation.
9 */
10
11#define pr_fmt(fmt) "ACPI configfs: " fmt
12
13#include <linux/init.h>
14#include <linux/module.h>
15#include <linux/configfs.h>
16#include <linux/acpi.h>
17
18#include "acpica/accommon.h"
19#include "acpica/actables.h"
20
21static struct config_group *acpi_table_group;
22
23struct acpi_table {
24 struct config_item cfg;
25 struct acpi_table_header *header;
26 u32 index;
27};
28
29static ssize_t acpi_table_aml_write(struct config_item *cfg,
30 const void *data, size_t size)
31{
32 const struct acpi_table_header *header = data;
33 struct acpi_table *table;
34 int ret;
35
36 table = container_of(cfg, struct acpi_table, cfg);
37
38 if (table->header) {
39 pr_err("table already loaded\n");
40 return -EBUSY;
41 }
42
43 if (header->length != size) {
44 pr_err("invalid table length\n");
45 return -EINVAL;
46 }
47
48 if (memcmp(header->signature, ACPI_SIG_SSDT, 4)) {
49 pr_err("invalid table signature\n");
50 return -EINVAL;
51 }
52
53 table = container_of(cfg, struct acpi_table, cfg);
54
55 table->header = kmemdup(header, header->length, GFP_KERNEL);
56 if (!table->header)
57 return -ENOMEM;
58
59 ACPI_INFO(("Host-directed Dynamic ACPI Table Load:"));
60 ret = acpi_tb_install_and_load_table(
61 ACPI_PTR_TO_PHYSADDR(table->header),
62 ACPI_TABLE_ORIGIN_EXTERNAL_VIRTUAL, FALSE,
63 &table->index);
64 if (ret) {
65 kfree(table->header);
66 table->header = NULL;
67 }
68
69 return ret;
70}
71
72static inline struct acpi_table_header *get_header(struct config_item *cfg)
73{
74 struct acpi_table *table = container_of(cfg, struct acpi_table, cfg);
75
76 if (!table->header)
77 pr_err("table not loaded\n");
78
79 return table->header;
80}
81
82static ssize_t acpi_table_aml_read(struct config_item *cfg,
83 void *data, size_t size)
84{
85 struct acpi_table_header *h = get_header(cfg);
86
87 if (!h)
88 return -EINVAL;
89
90 if (data)
91 memcpy(data, h, h->length);
92
93 return h->length;
94}
95
96#define MAX_ACPI_TABLE_SIZE (128 * 1024)
97
98CONFIGFS_BIN_ATTR(acpi_table_, aml, NULL, MAX_ACPI_TABLE_SIZE);
99
100static struct configfs_bin_attribute *acpi_table_bin_attrs[] = {
101 &acpi_table_attr_aml,
102 NULL,
103};
104
105static ssize_t acpi_table_signature_show(struct config_item *cfg, char *str)
106{
107 struct acpi_table_header *h = get_header(cfg);
108
109 if (!h)
110 return -EINVAL;
111
112 return sprintf(str, "%.*s\n", ACPI_NAME_SIZE, h->signature);
113}
114
115static ssize_t acpi_table_length_show(struct config_item *cfg, char *str)
116{
117 struct acpi_table_header *h = get_header(cfg);
118
119 if (!h)
120 return -EINVAL;
121
122 return sprintf(str, "%d\n", h->length);
123}
124
125static ssize_t acpi_table_revision_show(struct config_item *cfg, char *str)
126{
127 struct acpi_table_header *h = get_header(cfg);
128
129 if (!h)
130 return -EINVAL;
131
132 return sprintf(str, "%d\n", h->revision);
133}
134
135static ssize_t acpi_table_oem_id_show(struct config_item *cfg, char *str)
136{
137 struct acpi_table_header *h = get_header(cfg);
138
139 if (!h)
140 return -EINVAL;
141
142 return sprintf(str, "%.*s\n", ACPI_OEM_ID_SIZE, h->oem_id);
143}
144
145static ssize_t acpi_table_oem_table_id_show(struct config_item *cfg, char *str)
146{
147 struct acpi_table_header *h = get_header(cfg);
148
149 if (!h)
150 return -EINVAL;
151
152 return sprintf(str, "%.*s\n", ACPI_OEM_TABLE_ID_SIZE, h->oem_table_id);
153}
154
155static ssize_t acpi_table_oem_revision_show(struct config_item *cfg, char *str)
156{
157 struct acpi_table_header *h = get_header(cfg);
158
159 if (!h)
160 return -EINVAL;
161
162 return sprintf(str, "%d\n", h->oem_revision);
163}
164
165static ssize_t acpi_table_asl_compiler_id_show(struct config_item *cfg,
166 char *str)
167{
168 struct acpi_table_header *h = get_header(cfg);
169
170 if (!h)
171 return -EINVAL;
172
173 return sprintf(str, "%.*s\n", ACPI_NAME_SIZE, h->asl_compiler_id);
174}
175
176static ssize_t acpi_table_asl_compiler_revision_show(struct config_item *cfg,
177 char *str)
178{
179 struct acpi_table_header *h = get_header(cfg);
180
181 if (!h)
182 return -EINVAL;
183
184 return sprintf(str, "%d\n", h->asl_compiler_revision);
185}
186
187CONFIGFS_ATTR_RO(acpi_table_, signature);
188CONFIGFS_ATTR_RO(acpi_table_, length);
189CONFIGFS_ATTR_RO(acpi_table_, revision);
190CONFIGFS_ATTR_RO(acpi_table_, oem_id);
191CONFIGFS_ATTR_RO(acpi_table_, oem_table_id);
192CONFIGFS_ATTR_RO(acpi_table_, oem_revision);
193CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_id);
194CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_revision);
195
196static struct configfs_attribute *acpi_table_attrs[] = {
197 &acpi_table_attr_signature,
198 &acpi_table_attr_length,
199 &acpi_table_attr_revision,
200 &acpi_table_attr_oem_id,
201 &acpi_table_attr_oem_table_id,
202 &acpi_table_attr_oem_revision,
203 &acpi_table_attr_asl_compiler_id,
204 &acpi_table_attr_asl_compiler_revision,
205 NULL,
206};
207
208static const struct config_item_type acpi_table_type = {
209 .ct_owner = THIS_MODULE,
210 .ct_bin_attrs = acpi_table_bin_attrs,
211 .ct_attrs = acpi_table_attrs,
212};
213
214static struct config_item *acpi_table_make_item(struct config_group *group,
215 const char *name)
216{
217 struct acpi_table *table;
218
219 table = kzalloc(sizeof(*table), GFP_KERNEL);
220 if (!table)
221 return ERR_PTR(-ENOMEM);
222
223 config_item_init_type_name(&table->cfg, name, &acpi_table_type);
224 return &table->cfg;
225}
226
227static void acpi_table_drop_item(struct config_group *group,
228 struct config_item *cfg)
229{
230 struct acpi_table *table = container_of(cfg, struct acpi_table, cfg);
231
232 ACPI_INFO(("Host-directed Dynamic ACPI Table Unload"));
233 acpi_tb_unload_table(table->index);
234}
235
236static struct configfs_group_operations acpi_table_group_ops = {
237 .make_item = acpi_table_make_item,
238 .drop_item = acpi_table_drop_item,
239};
240
241static const struct config_item_type acpi_tables_type = {
242 .ct_owner = THIS_MODULE,
243 .ct_group_ops = &acpi_table_group_ops,
244};
245
246static const struct config_item_type acpi_root_group_type = {
247 .ct_owner = THIS_MODULE,
248};
249
250static struct configfs_subsystem acpi_configfs = {
251 .su_group = {
252 .cg_item = {
253 .ci_namebuf = "acpi",
254 .ci_type = &acpi_root_group_type,
255 },
256 },
257 .su_mutex = __MUTEX_INITIALIZER(acpi_configfs.su_mutex),
258};
259
260static int __init acpi_configfs_init(void)
261{
262 int ret;
263 struct config_group *root = &acpi_configfs.su_group;
264
265 config_group_init(root);
266
267 ret = configfs_register_subsystem(&acpi_configfs);
268 if (ret)
269 return ret;
270
271 acpi_table_group = configfs_register_default_group(root, "table",
272 &acpi_tables_type);
273 return PTR_ERR_OR_ZERO(acpi_table_group);
274}
275module_init(acpi_configfs_init);
276
277static void __exit acpi_configfs_exit(void)
278{
279 configfs_unregister_default_group(acpi_table_group);
280 configfs_unregister_subsystem(&acpi_configfs);
281}
282module_exit(acpi_configfs_exit);
283
284MODULE_AUTHOR("Octavian Purdila <octavian.purdila@intel.com>");
285MODULE_DESCRIPTION("ACPI configfs support");
286MODULE_LICENSE("GPL v2");
287