tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * ACPI configfs support
4 *
5 * Copyright (c) 2016 Intel Corporation
6 */
7
8#define pr_fmt(fmt) "ACPI configfs: " fmt
9
10#include <linux/init.h>
11#include <linux/module.h>
12#include <linux/configfs.h>
13#include <linux/acpi.h>
14
15#include "acpica/accommon.h"
16#include "acpica/actables.h"
17
18static struct config_group *acpi_table_group;
19
20struct acpi_table {
21 struct config_item cfg;
22 struct acpi_table_header *header;
23 u32 index;
24};
25
26static ssize_t acpi_table_aml_write(struct config_item *cfg,
27 const void *data, size_t size)
28{
29 const struct acpi_table_header *header = data;
30 struct acpi_table *table;
31 int ret;
32
33 table = container_of(cfg, struct acpi_table, cfg);
34
35 if (table->header) {
36 pr_err("table already loaded\n");
37 return -EBUSY;
38 }
39
40 if (header->length != size) {
41 pr_err("invalid table length\n");
42 return -EINVAL;
43 }
44
45 if (memcmp(header->signature, ACPI_SIG_SSDT, 4)) {
46 pr_err("invalid table signature\n");
47 return -EINVAL;
48 }
49
50 table = container_of(cfg, struct acpi_table, cfg);
51
52 table->header = kmemdup(header, header->length, GFP_KERNEL);
53 if (!table->header)
54 return -ENOMEM;
55
56 ACPI_INFO(("Host-directed Dynamic ACPI Table Load:"));
57 ret = acpi_tb_install_and_load_table(
58 ACPI_PTR_TO_PHYSADDR(table->header),
59 ACPI_TABLE_ORIGIN_EXTERNAL_VIRTUAL, FALSE,
60 &table->index);
61 if (ret) {
62 kfree(table->header);
63 table->header = NULL;
64 }
65
66 return ret;
67}
68
69static inline struct acpi_table_header *get_header(struct config_item *cfg)
70{
71 struct acpi_table *table = container_of(cfg, struct acpi_table, cfg);
72
73 if (!table->header)
74 pr_err("table not loaded\n");
75
76 return table->header;
77}
78
79static ssize_t acpi_table_aml_read(struct config_item *cfg,
80 void *data, size_t size)
81{
82 struct acpi_table_header *h = get_header(cfg);
83
84 if (!h)
85 return -EINVAL;
86
87 if (data)
88 memcpy(data, h, h->length);
89
90 return h->length;
91}
92
93#define MAX_ACPI_TABLE_SIZE (128 * 1024)
94
95CONFIGFS_BIN_ATTR(acpi_table_, aml, NULL, MAX_ACPI_TABLE_SIZE);
96
97static struct configfs_bin_attribute *acpi_table_bin_attrs[] = {
98 &acpi_table_attr_aml,
99 NULL,
100};
101
102static ssize_t acpi_table_signature_show(struct config_item *cfg, char *str)
103{
104 struct acpi_table_header *h = get_header(cfg);
105
106 if (!h)
107 return -EINVAL;
108
109 return sprintf(str, "%.*s\n", ACPI_NAMESEG_SIZE, h->signature);
110}
111
112static ssize_t acpi_table_length_show(struct config_item *cfg, char *str)
113{
114 struct acpi_table_header *h = get_header(cfg);
115
116 if (!h)
117 return -EINVAL;
118
119 return sprintf(str, "%d\n", h->length);
120}
121
122static ssize_t acpi_table_revision_show(struct config_item *cfg, char *str)
123{
124 struct acpi_table_header *h = get_header(cfg);
125
126 if (!h)
127 return -EINVAL;
128
129 return sprintf(str, "%d\n", h->revision);
130}
131
132static ssize_t acpi_table_oem_id_show(struct config_item *cfg, char *str)
133{
134 struct acpi_table_header *h = get_header(cfg);
135
136 if (!h)
137 return -EINVAL;
138
139 return sprintf(str, "%.*s\n", ACPI_OEM_ID_SIZE, h->oem_id);
140}
141
142static ssize_t acpi_table_oem_table_id_show(struct config_item *cfg, char *str)
143{
144 struct acpi_table_header *h = get_header(cfg);
145
146 if (!h)
147 return -EINVAL;
148
149 return sprintf(str, "%.*s\n", ACPI_OEM_TABLE_ID_SIZE, h->oem_table_id);
150}
151
152static ssize_t acpi_table_oem_revision_show(struct config_item *cfg, char *str)
153{
154 struct acpi_table_header *h = get_header(cfg);
155
156 if (!h)
157 return -EINVAL;
158
159 return sprintf(str, "%d\n", h->oem_revision);
160}
161
162static ssize_t acpi_table_asl_compiler_id_show(struct config_item *cfg,
163 char *str)
164{
165 struct acpi_table_header *h = get_header(cfg);
166
167 if (!h)
168 return -EINVAL;
169
170 return sprintf(str, "%.*s\n", ACPI_NAMESEG_SIZE, h->asl_compiler_id);
171}
172
173static ssize_t acpi_table_asl_compiler_revision_show(struct config_item *cfg,
174 char *str)
175{
176 struct acpi_table_header *h = get_header(cfg);
177
178 if (!h)
179 return -EINVAL;
180
181 return sprintf(str, "%d\n", h->asl_compiler_revision);
182}
183
184CONFIGFS_ATTR_RO(acpi_table_, signature);
185CONFIGFS_ATTR_RO(acpi_table_, length);
186CONFIGFS_ATTR_RO(acpi_table_, revision);
187CONFIGFS_ATTR_RO(acpi_table_, oem_id);
188CONFIGFS_ATTR_RO(acpi_table_, oem_table_id);
189CONFIGFS_ATTR_RO(acpi_table_, oem_revision);
190CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_id);
191CONFIGFS_ATTR_RO(acpi_table_, asl_compiler_revision);
192
193static struct configfs_attribute *acpi_table_attrs[] = {
194 &acpi_table_attr_signature,
195 &acpi_table_attr_length,
196 &acpi_table_attr_revision,
197 &acpi_table_attr_oem_id,
198 &acpi_table_attr_oem_table_id,
199 &acpi_table_attr_oem_revision,
200 &acpi_table_attr_asl_compiler_id,
201 &acpi_table_attr_asl_compiler_revision,
202 NULL,
203};
204
205static const struct config_item_type acpi_table_type = {
206 .ct_owner = THIS_MODULE,
207 .ct_bin_attrs = acpi_table_bin_attrs,
208 .ct_attrs = acpi_table_attrs,
209};
210
211static struct config_item *acpi_table_make_item(struct config_group *group,
212 const char *name)
213{
214 struct acpi_table *table;
215
216 table = kzalloc(sizeof(*table), GFP_KERNEL);
217 if (!table)
218 return ERR_PTR(-ENOMEM);
219
220 config_item_init_type_name(&table->cfg, name, &acpi_table_type);
221 return &table->cfg;
222}
223
224static void acpi_table_drop_item(struct config_group *group,
225 struct config_item *cfg)
226{
227 struct acpi_table *table = container_of(cfg, struct acpi_table, cfg);
228
229 ACPI_INFO(("Host-directed Dynamic ACPI Table Unload"));
230 acpi_tb_unload_table(table->index);
231}
232
233static struct configfs_group_operations acpi_table_group_ops = {
234 .make_item = acpi_table_make_item,
235 .drop_item = acpi_table_drop_item,
236};
237
238static const struct config_item_type acpi_tables_type = {
239 .ct_owner = THIS_MODULE,
240 .ct_group_ops = &acpi_table_group_ops,
241};
242
243static const struct config_item_type acpi_root_group_type = {
244 .ct_owner = THIS_MODULE,
245};
246
247static struct configfs_subsystem acpi_configfs = {
248 .su_group = {
249 .cg_item = {
250 .ci_namebuf = "acpi",
251 .ci_type = &acpi_root_group_type,
252 },
253 },
254 .su_mutex = __MUTEX_INITIALIZER(acpi_configfs.su_mutex),
255};
256
257static int __init acpi_configfs_init(void)
258{
259 int ret;
260 struct config_group *root = &acpi_configfs.su_group;
261
262 config_group_init(root);
263
264 ret = configfs_register_subsystem(&acpi_configfs);
265 if (ret)
266 return ret;
267
268 acpi_table_group = configfs_register_default_group(root, "table",
269 &acpi_tables_type);
270 return PTR_ERR_OR_ZERO(acpi_table_group);
271}
272module_init(acpi_configfs_init);
273
274static void __exit acpi_configfs_exit(void)
275{
276 configfs_unregister_default_group(acpi_table_group);
277 configfs_unregister_subsystem(&acpi_configfs);
278}
279module_exit(acpi_configfs_exit);
280
281MODULE_AUTHOR("Octavian Purdila <octavian.purdila@intel.com>");
282MODULE_DESCRIPTION("ACPI configfs support");
283MODULE_LICENSE("GPL v2");