diff options
Diffstat (limited to 'drivers/firmware/dmi-sysfs.c')
-rw-r--r-- | drivers/firmware/dmi-sysfs.c | 696 |
1 files changed, 696 insertions, 0 deletions
diff --git a/drivers/firmware/dmi-sysfs.c b/drivers/firmware/dmi-sysfs.c new file mode 100644 index 000000000000..eb26d62e5188 --- /dev/null +++ b/drivers/firmware/dmi-sysfs.c | |||
@@ -0,0 +1,696 @@ | |||
1 | /* | ||
2 | * dmi-sysfs.c | ||
3 | * | ||
4 | * This module exports the DMI tables read-only to userspace through the | ||
5 | * sysfs file system. | ||
6 | * | ||
7 | * Data is currently found below | ||
8 | * /sys/firmware/dmi/... | ||
9 | * | ||
10 | * DMI attributes are presented in attribute files with names | ||
11 | * formatted using %d-%d, so that the first integer indicates the | ||
12 | * structure type (0-255), and the second field is the instance of that | ||
13 | * entry. | ||
14 | * | ||
15 | * Copyright 2011 Google, Inc. | ||
16 | */ | ||
17 | |||
18 | #include <linux/kernel.h> | ||
19 | #include <linux/init.h> | ||
20 | #include <linux/module.h> | ||
21 | #include <linux/types.h> | ||
22 | #include <linux/kobject.h> | ||
23 | #include <linux/dmi.h> | ||
24 | #include <linux/capability.h> | ||
25 | #include <linux/slab.h> | ||
26 | #include <linux/list.h> | ||
27 | #include <linux/io.h> | ||
28 | |||
29 | #define MAX_ENTRY_TYPE 255 /* Most of these aren't used, but we consider | ||
30 | the top entry type is only 8 bits */ | ||
31 | |||
32 | struct dmi_sysfs_entry { | ||
33 | struct dmi_header dh; | ||
34 | struct kobject kobj; | ||
35 | int instance; | ||
36 | int position; | ||
37 | struct list_head list; | ||
38 | struct kobject *child; | ||
39 | }; | ||
40 | |||
41 | /* | ||
42 | * Global list of dmi_sysfs_entry. Even though this should only be | ||
43 | * manipulated at setup and teardown, the lazy nature of the kobject | ||
44 | * system means we get lazy removes. | ||
45 | */ | ||
46 | static LIST_HEAD(entry_list); | ||
47 | static DEFINE_SPINLOCK(entry_list_lock); | ||
48 | |||
49 | /* dmi_sysfs_attribute - Top level attribute. used by all entries. */ | ||
50 | struct dmi_sysfs_attribute { | ||
51 | struct attribute attr; | ||
52 | ssize_t (*show)(struct dmi_sysfs_entry *entry, char *buf); | ||
53 | }; | ||
54 | |||
55 | #define DMI_SYSFS_ATTR(_entry, _name) \ | ||
56 | struct dmi_sysfs_attribute dmi_sysfs_attr_##_entry##_##_name = { \ | ||
57 | .attr = {.name = __stringify(_name), .mode = 0400}, \ | ||
58 | .show = dmi_sysfs_##_entry##_##_name, \ | ||
59 | } | ||
60 | |||
61 | /* | ||
62 | * dmi_sysfs_mapped_attribute - Attribute where we require the entry be | ||
63 | * mapped in. Use in conjunction with dmi_sysfs_specialize_attr_ops. | ||
64 | */ | ||
65 | struct dmi_sysfs_mapped_attribute { | ||
66 | struct attribute attr; | ||
67 | ssize_t (*show)(struct dmi_sysfs_entry *entry, | ||
68 | const struct dmi_header *dh, | ||
69 | char *buf); | ||
70 | }; | ||
71 | |||
72 | #define DMI_SYSFS_MAPPED_ATTR(_entry, _name) \ | ||
73 | struct dmi_sysfs_mapped_attribute dmi_sysfs_attr_##_entry##_##_name = { \ | ||
74 | .attr = {.name = __stringify(_name), .mode = 0400}, \ | ||
75 | .show = dmi_sysfs_##_entry##_##_name, \ | ||
76 | } | ||
77 | |||
78 | /************************************************* | ||
79 | * Generic DMI entry support. | ||
80 | *************************************************/ | ||
81 | static void dmi_entry_free(struct kobject *kobj) | ||
82 | { | ||
83 | kfree(kobj); | ||
84 | } | ||
85 | |||
86 | static struct dmi_sysfs_entry *to_entry(struct kobject *kobj) | ||
87 | { | ||
88 | return container_of(kobj, struct dmi_sysfs_entry, kobj); | ||
89 | } | ||
90 | |||
91 | static struct dmi_sysfs_attribute *to_attr(struct attribute *attr) | ||
92 | { | ||
93 | return container_of(attr, struct dmi_sysfs_attribute, attr); | ||
94 | } | ||
95 | |||
96 | static ssize_t dmi_sysfs_attr_show(struct kobject *kobj, | ||
97 | struct attribute *_attr, char *buf) | ||
98 | { | ||
99 | struct dmi_sysfs_entry *entry = to_entry(kobj); | ||
100 | struct dmi_sysfs_attribute *attr = to_attr(_attr); | ||
101 | |||
102 | /* DMI stuff is only ever admin visible */ | ||
103 | if (!capable(CAP_SYS_ADMIN)) | ||
104 | return -EACCES; | ||
105 | |||
106 | return attr->show(entry, buf); | ||
107 | } | ||
108 | |||
109 | static const struct sysfs_ops dmi_sysfs_attr_ops = { | ||
110 | .show = dmi_sysfs_attr_show, | ||
111 | }; | ||
112 | |||
113 | typedef ssize_t (*dmi_callback)(struct dmi_sysfs_entry *, | ||
114 | const struct dmi_header *dh, void *); | ||
115 | |||
116 | struct find_dmi_data { | ||
117 | struct dmi_sysfs_entry *entry; | ||
118 | dmi_callback callback; | ||
119 | void *private; | ||
120 | int instance_countdown; | ||
121 | ssize_t ret; | ||
122 | }; | ||
123 | |||
124 | static void find_dmi_entry_helper(const struct dmi_header *dh, | ||
125 | void *_data) | ||
126 | { | ||
127 | struct find_dmi_data *data = _data; | ||
128 | struct dmi_sysfs_entry *entry = data->entry; | ||
129 | |||
130 | /* Is this the entry we want? */ | ||
131 | if (dh->type != entry->dh.type) | ||
132 | return; | ||
133 | |||
134 | if (data->instance_countdown != 0) { | ||
135 | /* try the next instance? */ | ||
136 | data->instance_countdown--; | ||
137 | return; | ||
138 | } | ||
139 | |||
140 | /* | ||
141 | * Don't ever revisit the instance. Short circuit later | ||
142 | * instances by letting the instance_countdown run negative | ||
143 | */ | ||
144 | data->instance_countdown--; | ||
145 | |||
146 | /* Found the entry */ | ||
147 | data->ret = data->callback(entry, dh, data->private); | ||
148 | } | ||
149 | |||
150 | /* State for passing the read parameters through dmi_find_entry() */ | ||
151 | struct dmi_read_state { | ||
152 | char *buf; | ||
153 | loff_t pos; | ||
154 | size_t count; | ||
155 | }; | ||
156 | |||
157 | static ssize_t find_dmi_entry(struct dmi_sysfs_entry *entry, | ||
158 | dmi_callback callback, void *private) | ||
159 | { | ||
160 | struct find_dmi_data data = { | ||
161 | .entry = entry, | ||
162 | .callback = callback, | ||
163 | .private = private, | ||
164 | .instance_countdown = entry->instance, | ||
165 | .ret = -EIO, /* To signal the entry disappeared */ | ||
166 | }; | ||
167 | int ret; | ||
168 | |||
169 | ret = dmi_walk(find_dmi_entry_helper, &data); | ||
170 | /* This shouldn't happen, but just in case. */ | ||
171 | if (ret) | ||
172 | return -EINVAL; | ||
173 | return data.ret; | ||
174 | } | ||
175 | |||
176 | /* | ||
177 | * Calculate and return the byte length of the dmi entry identified by | ||
178 | * dh. This includes both the formatted portion as well as the | ||
179 | * unformatted string space, including the two trailing nul characters. | ||
180 | */ | ||
181 | static size_t dmi_entry_length(const struct dmi_header *dh) | ||
182 | { | ||
183 | const char *p = (const char *)dh; | ||
184 | |||
185 | p += dh->length; | ||
186 | |||
187 | while (p[0] || p[1]) | ||
188 | p++; | ||
189 | |||
190 | return 2 + p - (const char *)dh; | ||
191 | } | ||
192 | |||
193 | /************************************************* | ||
194 | * Support bits for specialized DMI entry support | ||
195 | *************************************************/ | ||
196 | struct dmi_entry_attr_show_data { | ||
197 | struct attribute *attr; | ||
198 | char *buf; | ||
199 | }; | ||
200 | |||
201 | static ssize_t dmi_entry_attr_show_helper(struct dmi_sysfs_entry *entry, | ||
202 | const struct dmi_header *dh, | ||
203 | void *_data) | ||
204 | { | ||
205 | struct dmi_entry_attr_show_data *data = _data; | ||
206 | struct dmi_sysfs_mapped_attribute *attr; | ||
207 | |||
208 | attr = container_of(data->attr, | ||
209 | struct dmi_sysfs_mapped_attribute, attr); | ||
210 | return attr->show(entry, dh, data->buf); | ||
211 | } | ||
212 | |||
213 | static ssize_t dmi_entry_attr_show(struct kobject *kobj, | ||
214 | struct attribute *attr, | ||
215 | char *buf) | ||
216 | { | ||
217 | struct dmi_entry_attr_show_data data = { | ||
218 | .attr = attr, | ||
219 | .buf = buf, | ||
220 | }; | ||
221 | /* Find the entry according to our parent and call the | ||
222 | * normalized show method hanging off of the attribute */ | ||
223 | return find_dmi_entry(to_entry(kobj->parent), | ||
224 | dmi_entry_attr_show_helper, &data); | ||
225 | } | ||
226 | |||
227 | static const struct sysfs_ops dmi_sysfs_specialize_attr_ops = { | ||
228 | .show = dmi_entry_attr_show, | ||
229 | }; | ||
230 | |||
231 | /************************************************* | ||
232 | * Specialized DMI entry support. | ||
233 | *************************************************/ | ||
234 | |||
235 | /*** Type 15 - System Event Table ***/ | ||
236 | |||
237 | #define DMI_SEL_ACCESS_METHOD_IO8 0x00 | ||
238 | #define DMI_SEL_ACCESS_METHOD_IO2x8 0x01 | ||
239 | #define DMI_SEL_ACCESS_METHOD_IO16 0x02 | ||
240 | #define DMI_SEL_ACCESS_METHOD_PHYS32 0x03 | ||
241 | #define DMI_SEL_ACCESS_METHOD_GPNV 0x04 | ||
242 | |||
243 | struct dmi_system_event_log { | ||
244 | struct dmi_header header; | ||
245 | u16 area_length; | ||
246 | u16 header_start_offset; | ||
247 | u16 data_start_offset; | ||
248 | u8 access_method; | ||
249 | u8 status; | ||
250 | u32 change_token; | ||
251 | union { | ||
252 | struct { | ||
253 | u16 index_addr; | ||
254 | u16 data_addr; | ||
255 | } io; | ||
256 | u32 phys_addr32; | ||
257 | u16 gpnv_handle; | ||
258 | u32 access_method_address; | ||
259 | }; | ||
260 | u8 header_format; | ||
261 | u8 type_descriptors_supported_count; | ||
262 | u8 per_log_type_descriptor_length; | ||
263 | u8 supported_log_type_descriptos[0]; | ||
264 | } __packed; | ||
265 | |||
266 | #define DMI_SYSFS_SEL_FIELD(_field) \ | ||
267 | static ssize_t dmi_sysfs_sel_##_field(struct dmi_sysfs_entry *entry, \ | ||
268 | const struct dmi_header *dh, \ | ||
269 | char *buf) \ | ||
270 | { \ | ||
271 | struct dmi_system_event_log sel; \ | ||
272 | if (sizeof(sel) > dmi_entry_length(dh)) \ | ||
273 | return -EIO; \ | ||
274 | memcpy(&sel, dh, sizeof(sel)); \ | ||
275 | return sprintf(buf, "%u\n", sel._field); \ | ||
276 | } \ | ||
277 | static DMI_SYSFS_MAPPED_ATTR(sel, _field) | ||
278 | |||
279 | DMI_SYSFS_SEL_FIELD(area_length); | ||
280 | DMI_SYSFS_SEL_FIELD(header_start_offset); | ||
281 | DMI_SYSFS_SEL_FIELD(data_start_offset); | ||
282 | DMI_SYSFS_SEL_FIELD(access_method); | ||
283 | DMI_SYSFS_SEL_FIELD(status); | ||
284 | DMI_SYSFS_SEL_FIELD(change_token); | ||
285 | DMI_SYSFS_SEL_FIELD(access_method_address); | ||
286 | DMI_SYSFS_SEL_FIELD(header_format); | ||
287 | DMI_SYSFS_SEL_FIELD(type_descriptors_supported_count); | ||
288 | DMI_SYSFS_SEL_FIELD(per_log_type_descriptor_length); | ||
289 | |||
290 | static struct attribute *dmi_sysfs_sel_attrs[] = { | ||
291 | &dmi_sysfs_attr_sel_area_length.attr, | ||
292 | &dmi_sysfs_attr_sel_header_start_offset.attr, | ||
293 | &dmi_sysfs_attr_sel_data_start_offset.attr, | ||
294 | &dmi_sysfs_attr_sel_access_method.attr, | ||
295 | &dmi_sysfs_attr_sel_status.attr, | ||
296 | &dmi_sysfs_attr_sel_change_token.attr, | ||
297 | &dmi_sysfs_attr_sel_access_method_address.attr, | ||
298 | &dmi_sysfs_attr_sel_header_format.attr, | ||
299 | &dmi_sysfs_attr_sel_type_descriptors_supported_count.attr, | ||
300 | &dmi_sysfs_attr_sel_per_log_type_descriptor_length.attr, | ||
301 | NULL, | ||
302 | }; | ||
303 | |||
304 | |||
305 | static struct kobj_type dmi_system_event_log_ktype = { | ||
306 | .release = dmi_entry_free, | ||
307 | .sysfs_ops = &dmi_sysfs_specialize_attr_ops, | ||
308 | .default_attrs = dmi_sysfs_sel_attrs, | ||
309 | }; | ||
310 | |||
311 | typedef u8 (*sel_io_reader)(const struct dmi_system_event_log *sel, | ||
312 | loff_t offset); | ||
313 | |||
314 | static DEFINE_MUTEX(io_port_lock); | ||
315 | |||
316 | static u8 read_sel_8bit_indexed_io(const struct dmi_system_event_log *sel, | ||
317 | loff_t offset) | ||
318 | { | ||
319 | u8 ret; | ||
320 | |||
321 | mutex_lock(&io_port_lock); | ||
322 | outb((u8)offset, sel->io.index_addr); | ||
323 | ret = inb(sel->io.data_addr); | ||
324 | mutex_unlock(&io_port_lock); | ||
325 | return ret; | ||
326 | } | ||
327 | |||
328 | static u8 read_sel_2x8bit_indexed_io(const struct dmi_system_event_log *sel, | ||
329 | loff_t offset) | ||
330 | { | ||
331 | u8 ret; | ||
332 | |||
333 | mutex_lock(&io_port_lock); | ||
334 | outb((u8)offset, sel->io.index_addr); | ||
335 | outb((u8)(offset >> 8), sel->io.index_addr + 1); | ||
336 | ret = inb(sel->io.data_addr); | ||
337 | mutex_unlock(&io_port_lock); | ||
338 | return ret; | ||
339 | } | ||
340 | |||
341 | static u8 read_sel_16bit_indexed_io(const struct dmi_system_event_log *sel, | ||
342 | loff_t offset) | ||
343 | { | ||
344 | u8 ret; | ||
345 | |||
346 | mutex_lock(&io_port_lock); | ||
347 | outw((u16)offset, sel->io.index_addr); | ||
348 | ret = inb(sel->io.data_addr); | ||
349 | mutex_unlock(&io_port_lock); | ||
350 | return ret; | ||
351 | } | ||
352 | |||
353 | static sel_io_reader sel_io_readers[] = { | ||
354 | [DMI_SEL_ACCESS_METHOD_IO8] = read_sel_8bit_indexed_io, | ||
355 | [DMI_SEL_ACCESS_METHOD_IO2x8] = read_sel_2x8bit_indexed_io, | ||
356 | [DMI_SEL_ACCESS_METHOD_IO16] = read_sel_16bit_indexed_io, | ||
357 | }; | ||
358 | |||
359 | static ssize_t dmi_sel_raw_read_io(struct dmi_sysfs_entry *entry, | ||
360 | const struct dmi_system_event_log *sel, | ||
361 | char *buf, loff_t pos, size_t count) | ||
362 | { | ||
363 | ssize_t wrote = 0; | ||
364 | |||
365 | sel_io_reader io_reader = sel_io_readers[sel->access_method]; | ||
366 | |||
367 | while (count && pos < sel->area_length) { | ||
368 | count--; | ||
369 | *(buf++) = io_reader(sel, pos++); | ||
370 | wrote++; | ||
371 | } | ||
372 | |||
373 | return wrote; | ||
374 | } | ||
375 | |||
376 | static ssize_t dmi_sel_raw_read_phys32(struct dmi_sysfs_entry *entry, | ||
377 | const struct dmi_system_event_log *sel, | ||
378 | char *buf, loff_t pos, size_t count) | ||
379 | { | ||
380 | u8 __iomem *mapped; | ||
381 | ssize_t wrote = 0; | ||
382 | |||
383 | mapped = ioremap(sel->access_method_address, sel->area_length); | ||
384 | if (!mapped) | ||
385 | return -EIO; | ||
386 | |||
387 | while (count && pos < sel->area_length) { | ||
388 | count--; | ||
389 | *(buf++) = readb(mapped + pos++); | ||
390 | wrote++; | ||
391 | } | ||
392 | |||
393 | iounmap(mapped); | ||
394 | return wrote; | ||
395 | } | ||
396 | |||
397 | static ssize_t dmi_sel_raw_read_helper(struct dmi_sysfs_entry *entry, | ||
398 | const struct dmi_header *dh, | ||
399 | void *_state) | ||
400 | { | ||
401 | struct dmi_read_state *state = _state; | ||
402 | struct dmi_system_event_log sel; | ||
403 | |||
404 | if (sizeof(sel) > dmi_entry_length(dh)) | ||
405 | return -EIO; | ||
406 | |||
407 | memcpy(&sel, dh, sizeof(sel)); | ||
408 | |||
409 | switch (sel.access_method) { | ||
410 | case DMI_SEL_ACCESS_METHOD_IO8: | ||
411 | case DMI_SEL_ACCESS_METHOD_IO2x8: | ||
412 | case DMI_SEL_ACCESS_METHOD_IO16: | ||
413 | return dmi_sel_raw_read_io(entry, &sel, state->buf, | ||
414 | state->pos, state->count); | ||
415 | case DMI_SEL_ACCESS_METHOD_PHYS32: | ||
416 | return dmi_sel_raw_read_phys32(entry, &sel, state->buf, | ||
417 | state->pos, state->count); | ||
418 | case DMI_SEL_ACCESS_METHOD_GPNV: | ||
419 | pr_info("dmi-sysfs: GPNV support missing.\n"); | ||
420 | return -EIO; | ||
421 | default: | ||
422 | pr_info("dmi-sysfs: Unknown access method %02x\n", | ||
423 | sel.access_method); | ||
424 | return -EIO; | ||
425 | } | ||
426 | } | ||
427 | |||
428 | static ssize_t dmi_sel_raw_read(struct file *filp, struct kobject *kobj, | ||
429 | struct bin_attribute *bin_attr, | ||
430 | char *buf, loff_t pos, size_t count) | ||
431 | { | ||
432 | struct dmi_sysfs_entry *entry = to_entry(kobj->parent); | ||
433 | struct dmi_read_state state = { | ||
434 | .buf = buf, | ||
435 | .pos = pos, | ||
436 | .count = count, | ||
437 | }; | ||
438 | |||
439 | return find_dmi_entry(entry, dmi_sel_raw_read_helper, &state); | ||
440 | } | ||
441 | |||
442 | static struct bin_attribute dmi_sel_raw_attr = { | ||
443 | .attr = {.name = "raw_event_log", .mode = 0400}, | ||
444 | .read = dmi_sel_raw_read, | ||
445 | }; | ||
446 | |||
447 | static int dmi_system_event_log(struct dmi_sysfs_entry *entry) | ||
448 | { | ||
449 | int ret; | ||
450 | |||
451 | entry->child = kzalloc(sizeof(*entry->child), GFP_KERNEL); | ||
452 | if (!entry->child) | ||
453 | return -ENOMEM; | ||
454 | ret = kobject_init_and_add(entry->child, | ||
455 | &dmi_system_event_log_ktype, | ||
456 | &entry->kobj, | ||
457 | "system_event_log"); | ||
458 | if (ret) | ||
459 | goto out_free; | ||
460 | |||
461 | ret = sysfs_create_bin_file(entry->child, &dmi_sel_raw_attr); | ||
462 | if (ret) | ||
463 | goto out_del; | ||
464 | |||
465 | return 0; | ||
466 | |||
467 | out_del: | ||
468 | kobject_del(entry->child); | ||
469 | out_free: | ||
470 | kfree(entry->child); | ||
471 | return ret; | ||
472 | } | ||
473 | |||
474 | /************************************************* | ||
475 | * Generic DMI entry support. | ||
476 | *************************************************/ | ||
477 | |||
478 | static ssize_t dmi_sysfs_entry_length(struct dmi_sysfs_entry *entry, char *buf) | ||
479 | { | ||
480 | return sprintf(buf, "%d\n", entry->dh.length); | ||
481 | } | ||
482 | |||
483 | static ssize_t dmi_sysfs_entry_handle(struct dmi_sysfs_entry *entry, char *buf) | ||
484 | { | ||
485 | return sprintf(buf, "%d\n", entry->dh.handle); | ||
486 | } | ||
487 | |||
488 | static ssize_t dmi_sysfs_entry_type(struct dmi_sysfs_entry *entry, char *buf) | ||
489 | { | ||
490 | return sprintf(buf, "%d\n", entry->dh.type); | ||
491 | } | ||
492 | |||
493 | static ssize_t dmi_sysfs_entry_instance(struct dmi_sysfs_entry *entry, | ||
494 | char *buf) | ||
495 | { | ||
496 | return sprintf(buf, "%d\n", entry->instance); | ||
497 | } | ||
498 | |||
499 | static ssize_t dmi_sysfs_entry_position(struct dmi_sysfs_entry *entry, | ||
500 | char *buf) | ||
501 | { | ||
502 | return sprintf(buf, "%d\n", entry->position); | ||
503 | } | ||
504 | |||
505 | static DMI_SYSFS_ATTR(entry, length); | ||
506 | static DMI_SYSFS_ATTR(entry, handle); | ||
507 | static DMI_SYSFS_ATTR(entry, type); | ||
508 | static DMI_SYSFS_ATTR(entry, instance); | ||
509 | static DMI_SYSFS_ATTR(entry, position); | ||
510 | |||
511 | static struct attribute *dmi_sysfs_entry_attrs[] = { | ||
512 | &dmi_sysfs_attr_entry_length.attr, | ||
513 | &dmi_sysfs_attr_entry_handle.attr, | ||
514 | &dmi_sysfs_attr_entry_type.attr, | ||
515 | &dmi_sysfs_attr_entry_instance.attr, | ||
516 | &dmi_sysfs_attr_entry_position.attr, | ||
517 | NULL, | ||
518 | }; | ||
519 | |||
520 | static ssize_t dmi_entry_raw_read_helper(struct dmi_sysfs_entry *entry, | ||
521 | const struct dmi_header *dh, | ||
522 | void *_state) | ||
523 | { | ||
524 | struct dmi_read_state *state = _state; | ||
525 | size_t entry_length; | ||
526 | |||
527 | entry_length = dmi_entry_length(dh); | ||
528 | |||
529 | return memory_read_from_buffer(state->buf, state->count, | ||
530 | &state->pos, dh, entry_length); | ||
531 | } | ||
532 | |||
533 | static ssize_t dmi_entry_raw_read(struct file *filp, | ||
534 | struct kobject *kobj, | ||
535 | struct bin_attribute *bin_attr, | ||
536 | char *buf, loff_t pos, size_t count) | ||
537 | { | ||
538 | struct dmi_sysfs_entry *entry = to_entry(kobj); | ||
539 | struct dmi_read_state state = { | ||
540 | .buf = buf, | ||
541 | .pos = pos, | ||
542 | .count = count, | ||
543 | }; | ||
544 | |||
545 | return find_dmi_entry(entry, dmi_entry_raw_read_helper, &state); | ||
546 | } | ||
547 | |||
548 | static const struct bin_attribute dmi_entry_raw_attr = { | ||
549 | .attr = {.name = "raw", .mode = 0400}, | ||
550 | .read = dmi_entry_raw_read, | ||
551 | }; | ||
552 | |||
553 | static void dmi_sysfs_entry_release(struct kobject *kobj) | ||
554 | { | ||
555 | struct dmi_sysfs_entry *entry = to_entry(kobj); | ||
556 | sysfs_remove_bin_file(&entry->kobj, &dmi_entry_raw_attr); | ||
557 | spin_lock(&entry_list_lock); | ||
558 | list_del(&entry->list); | ||
559 | spin_unlock(&entry_list_lock); | ||
560 | kfree(entry); | ||
561 | } | ||
562 | |||
563 | static struct kobj_type dmi_sysfs_entry_ktype = { | ||
564 | .release = dmi_sysfs_entry_release, | ||
565 | .sysfs_ops = &dmi_sysfs_attr_ops, | ||
566 | .default_attrs = dmi_sysfs_entry_attrs, | ||
567 | }; | ||
568 | |||
569 | static struct kobject *dmi_kobj; | ||
570 | static struct kset *dmi_kset; | ||
571 | |||
572 | /* Global count of all instances seen. Only for setup */ | ||
573 | static int __initdata instance_counts[MAX_ENTRY_TYPE + 1]; | ||
574 | |||
575 | /* Global positional count of all entries seen. Only for setup */ | ||
576 | static int __initdata position_count; | ||
577 | |||
578 | static void __init dmi_sysfs_register_handle(const struct dmi_header *dh, | ||
579 | void *_ret) | ||
580 | { | ||
581 | struct dmi_sysfs_entry *entry; | ||
582 | int *ret = _ret; | ||
583 | |||
584 | /* If a previous entry saw an error, short circuit */ | ||
585 | if (*ret) | ||
586 | return; | ||
587 | |||
588 | /* Allocate and register a new entry into the entries set */ | ||
589 | entry = kzalloc(sizeof(*entry), GFP_KERNEL); | ||
590 | if (!entry) { | ||
591 | *ret = -ENOMEM; | ||
592 | return; | ||
593 | } | ||
594 | |||
595 | /* Set the key */ | ||
596 | memcpy(&entry->dh, dh, sizeof(*dh)); | ||
597 | entry->instance = instance_counts[dh->type]++; | ||
598 | entry->position = position_count++; | ||
599 | |||
600 | entry->kobj.kset = dmi_kset; | ||
601 | *ret = kobject_init_and_add(&entry->kobj, &dmi_sysfs_entry_ktype, NULL, | ||
602 | "%d-%d", dh->type, entry->instance); | ||
603 | |||
604 | if (*ret) { | ||
605 | kfree(entry); | ||
606 | return; | ||
607 | } | ||
608 | |||
609 | /* Thread on the global list for cleanup */ | ||
610 | spin_lock(&entry_list_lock); | ||
611 | list_add_tail(&entry->list, &entry_list); | ||
612 | spin_unlock(&entry_list_lock); | ||
613 | |||
614 | /* Handle specializations by type */ | ||
615 | switch (dh->type) { | ||
616 | case DMI_ENTRY_SYSTEM_EVENT_LOG: | ||
617 | *ret = dmi_system_event_log(entry); | ||
618 | break; | ||
619 | default: | ||
620 | /* No specialization */ | ||
621 | break; | ||
622 | } | ||
623 | if (*ret) | ||
624 | goto out_err; | ||
625 | |||
626 | /* Create the raw binary file to access the entry */ | ||
627 | *ret = sysfs_create_bin_file(&entry->kobj, &dmi_entry_raw_attr); | ||
628 | if (*ret) | ||
629 | goto out_err; | ||
630 | |||
631 | return; | ||
632 | out_err: | ||
633 | kobject_put(entry->child); | ||
634 | kobject_put(&entry->kobj); | ||
635 | return; | ||
636 | } | ||
637 | |||
638 | static void cleanup_entry_list(void) | ||
639 | { | ||
640 | struct dmi_sysfs_entry *entry, *next; | ||
641 | |||
642 | /* No locks, we are on our way out */ | ||
643 | list_for_each_entry_safe(entry, next, &entry_list, list) { | ||
644 | kobject_put(entry->child); | ||
645 | kobject_put(&entry->kobj); | ||
646 | } | ||
647 | } | ||
648 | |||
649 | static int __init dmi_sysfs_init(void) | ||
650 | { | ||
651 | int error = -ENOMEM; | ||
652 | int val; | ||
653 | |||
654 | /* Set up our directory */ | ||
655 | dmi_kobj = kobject_create_and_add("dmi", firmware_kobj); | ||
656 | if (!dmi_kobj) | ||
657 | goto err; | ||
658 | |||
659 | dmi_kset = kset_create_and_add("entries", NULL, dmi_kobj); | ||
660 | if (!dmi_kset) | ||
661 | goto err; | ||
662 | |||
663 | val = 0; | ||
664 | error = dmi_walk(dmi_sysfs_register_handle, &val); | ||
665 | if (error) | ||
666 | goto err; | ||
667 | if (val) { | ||
668 | error = val; | ||
669 | goto err; | ||
670 | } | ||
671 | |||
672 | pr_debug("dmi-sysfs: loaded.\n"); | ||
673 | |||
674 | return 0; | ||
675 | err: | ||
676 | cleanup_entry_list(); | ||
677 | kset_unregister(dmi_kset); | ||
678 | kobject_put(dmi_kobj); | ||
679 | return error; | ||
680 | } | ||
681 | |||
682 | /* clean up everything. */ | ||
683 | static void __exit dmi_sysfs_exit(void) | ||
684 | { | ||
685 | pr_debug("dmi-sysfs: unloading.\n"); | ||
686 | cleanup_entry_list(); | ||
687 | kset_unregister(dmi_kset); | ||
688 | kobject_put(dmi_kobj); | ||
689 | } | ||
690 | |||
691 | module_init(dmi_sysfs_init); | ||
692 | module_exit(dmi_sysfs_exit); | ||
693 | |||
694 | MODULE_AUTHOR("Mike Waychison <mikew@google.com>"); | ||
695 | MODULE_DESCRIPTION("DMI sysfs support"); | ||
696 | MODULE_LICENSE("GPL"); | ||