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1/*
2 * file.c - part of debugfs, a tiny little debug file system
3 *
4 * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
5 * Copyright (C) 2004 IBM Inc.
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version
9 * 2 as published by the Free Software Foundation.
10 *
11 * debugfs is for people to use instead of /proc or /sys.
12 * See Documentation/DocBook/filesystems for more details.
13 *
14 */
15
16#include <linux/module.h>
17#include <linux/fs.h>
18#include <linux/pagemap.h>
19#include <linux/namei.h>
20#include <linux/debugfs.h>
21
22static ssize_t default_read_file(struct file *file, char __user *buf,
23 size_t count, loff_t *ppos)
24{
25 return 0;
26}
27
28static ssize_t default_write_file(struct file *file, const char __user *buf,
29 size_t count, loff_t *ppos)
30{
31 return count;
32}
33
34static int default_open(struct inode *inode, struct file *file)
35{
36 if (inode->i_private)
37 file->private_data = inode->i_private;
38
39 return 0;
40}
41
42const struct file_operations debugfs_file_operations = {
43 .read = default_read_file,
44 .write = default_write_file,
45 .open = default_open,
46 .llseek = noop_llseek,
47};
48
49static void *debugfs_follow_link(struct dentry *dentry, struct nameidata *nd)
50{
51 nd_set_link(nd, dentry->d_inode->i_private);
52 return NULL;
53}
54
55const struct inode_operations debugfs_link_operations = {
56 .readlink = generic_readlink,
57 .follow_link = debugfs_follow_link,
58};
59
60static int debugfs_u8_set(void *data, u64 val)
61{
62 *(u8 *)data = val;
63 return 0;
64}
65static int debugfs_u8_get(void *data, u64 *val)
66{
67 *val = *(u8 *)data;
68 return 0;
69}
70DEFINE_SIMPLE_ATTRIBUTE(fops_u8, debugfs_u8_get, debugfs_u8_set, "%llu\n");
71DEFINE_SIMPLE_ATTRIBUTE(fops_u8_ro, debugfs_u8_get, NULL, "%llu\n");
72DEFINE_SIMPLE_ATTRIBUTE(fops_u8_wo, NULL, debugfs_u8_set, "%llu\n");
73
74/**
75 * debugfs_create_u8 - create a debugfs file that is used to read and write an unsigned 8-bit value
76 * @name: a pointer to a string containing the name of the file to create.
77 * @mode: the permission that the file should have
78 * @parent: a pointer to the parent dentry for this file. This should be a
79 * directory dentry if set. If this parameter is %NULL, then the
80 * file will be created in the root of the debugfs filesystem.
81 * @value: a pointer to the variable that the file should read to and write
82 * from.
83 *
84 * This function creates a file in debugfs with the given name that
85 * contains the value of the variable @value. If the @mode variable is so
86 * set, it can be read from, and written to.
87 *
88 * This function will return a pointer to a dentry if it succeeds. This
89 * pointer must be passed to the debugfs_remove() function when the file is
90 * to be removed (no automatic cleanup happens if your module is unloaded,
91 * you are responsible here.) If an error occurs, %NULL will be returned.
92 *
93 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
94 * returned. It is not wise to check for this value, but rather, check for
95 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
96 * code.
97 */
98struct dentry *debugfs_create_u8(const char *name, mode_t mode,
99 struct dentry *parent, u8 *value)
100{
101 /* if there are no write bits set, make read only */
102 if (!(mode & S_IWUGO))
103 return debugfs_create_file(name, mode, parent, value, &fops_u8_ro);
104 /* if there are no read bits set, make write only */
105 if (!(mode & S_IRUGO))
106 return debugfs_create_file(name, mode, parent, value, &fops_u8_wo);
107
108 return debugfs_create_file(name, mode, parent, value, &fops_u8);
109}
110EXPORT_SYMBOL_GPL(debugfs_create_u8);
111
112static int debugfs_u16_set(void *data, u64 val)
113{
114 *(u16 *)data = val;
115 return 0;
116}
117static int debugfs_u16_get(void *data, u64 *val)
118{
119 *val = *(u16 *)data;
120 return 0;
121}
122DEFINE_SIMPLE_ATTRIBUTE(fops_u16, debugfs_u16_get, debugfs_u16_set, "%llu\n");
123DEFINE_SIMPLE_ATTRIBUTE(fops_u16_ro, debugfs_u16_get, NULL, "%llu\n");
124DEFINE_SIMPLE_ATTRIBUTE(fops_u16_wo, NULL, debugfs_u16_set, "%llu\n");
125
126/**
127 * debugfs_create_u16 - create a debugfs file that is used to read and write an unsigned 16-bit value
128 * @name: a pointer to a string containing the name of the file to create.
129 * @mode: the permission that the file should have
130 * @parent: a pointer to the parent dentry for this file. This should be a
131 * directory dentry if set. If this parameter is %NULL, then the
132 * file will be created in the root of the debugfs filesystem.
133 * @value: a pointer to the variable that the file should read to and write
134 * from.
135 *
136 * This function creates a file in debugfs with the given name that
137 * contains the value of the variable @value. If the @mode variable is so
138 * set, it can be read from, and written to.
139 *
140 * This function will return a pointer to a dentry if it succeeds. This
141 * pointer must be passed to the debugfs_remove() function when the file is
142 * to be removed (no automatic cleanup happens if your module is unloaded,
143 * you are responsible here.) If an error occurs, %NULL will be returned.
144 *
145 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
146 * returned. It is not wise to check for this value, but rather, check for
147 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
148 * code.
149 */
150struct dentry *debugfs_create_u16(const char *name, mode_t mode,
151 struct dentry *parent, u16 *value)
152{
153 /* if there are no write bits set, make read only */
154 if (!(mode & S_IWUGO))
155 return debugfs_create_file(name, mode, parent, value, &fops_u16_ro);
156 /* if there are no read bits set, make write only */
157 if (!(mode & S_IRUGO))
158 return debugfs_create_file(name, mode, parent, value, &fops_u16_wo);
159
160 return debugfs_create_file(name, mode, parent, value, &fops_u16);
161}
162EXPORT_SYMBOL_GPL(debugfs_create_u16);
163
164static int debugfs_u32_set(void *data, u64 val)
165{
166 *(u32 *)data = val;
167 return 0;
168}
169static int debugfs_u32_get(void *data, u64 *val)
170{
171 *val = *(u32 *)data;
172 return 0;
173}
174DEFINE_SIMPLE_ATTRIBUTE(fops_u32, debugfs_u32_get, debugfs_u32_set, "%llu\n");
175DEFINE_SIMPLE_ATTRIBUTE(fops_u32_ro, debugfs_u32_get, NULL, "%llu\n");
176DEFINE_SIMPLE_ATTRIBUTE(fops_u32_wo, NULL, debugfs_u32_set, "%llu\n");
177
178/**
179 * debugfs_create_u32 - create a debugfs file that is used to read and write an unsigned 32-bit value
180 * @name: a pointer to a string containing the name of the file to create.
181 * @mode: the permission that the file should have
182 * @parent: a pointer to the parent dentry for this file. This should be a
183 * directory dentry if set. If this parameter is %NULL, then the
184 * file will be created in the root of the debugfs filesystem.
185 * @value: a pointer to the variable that the file should read to and write
186 * from.
187 *
188 * This function creates a file in debugfs with the given name that
189 * contains the value of the variable @value. If the @mode variable is so
190 * set, it can be read from, and written to.
191 *
192 * This function will return a pointer to a dentry if it succeeds. This
193 * pointer must be passed to the debugfs_remove() function when the file is
194 * to be removed (no automatic cleanup happens if your module is unloaded,
195 * you are responsible here.) If an error occurs, %NULL will be returned.
196 *
197 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
198 * returned. It is not wise to check for this value, but rather, check for
199 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
200 * code.
201 */
202struct dentry *debugfs_create_u32(const char *name, mode_t mode,
203 struct dentry *parent, u32 *value)
204{
205 /* if there are no write bits set, make read only */
206 if (!(mode & S_IWUGO))
207 return debugfs_create_file(name, mode, parent, value, &fops_u32_ro);
208 /* if there are no read bits set, make write only */
209 if (!(mode & S_IRUGO))
210 return debugfs_create_file(name, mode, parent, value, &fops_u32_wo);
211
212 return debugfs_create_file(name, mode, parent, value, &fops_u32);
213}
214EXPORT_SYMBOL_GPL(debugfs_create_u32);
215
216static int debugfs_u64_set(void *data, u64 val)
217{
218 *(u64 *)data = val;
219 return 0;
220}
221
222static int debugfs_u64_get(void *data, u64 *val)
223{
224 *val = *(u64 *)data;
225 return 0;
226}
227DEFINE_SIMPLE_ATTRIBUTE(fops_u64, debugfs_u64_get, debugfs_u64_set, "%llu\n");
228DEFINE_SIMPLE_ATTRIBUTE(fops_u64_ro, debugfs_u64_get, NULL, "%llu\n");
229DEFINE_SIMPLE_ATTRIBUTE(fops_u64_wo, NULL, debugfs_u64_set, "%llu\n");
230
231/**
232 * debugfs_create_u64 - create a debugfs file that is used to read and write an unsigned 64-bit value
233 * @name: a pointer to a string containing the name of the file to create.
234 * @mode: the permission that the file should have
235 * @parent: a pointer to the parent dentry for this file. This should be a
236 * directory dentry if set. If this parameter is %NULL, then the
237 * file will be created in the root of the debugfs filesystem.
238 * @value: a pointer to the variable that the file should read to and write
239 * from.
240 *
241 * This function creates a file in debugfs with the given name that
242 * contains the value of the variable @value. If the @mode variable is so
243 * set, it can be read from, and written to.
244 *
245 * This function will return a pointer to a dentry if it succeeds. This
246 * pointer must be passed to the debugfs_remove() function when the file is
247 * to be removed (no automatic cleanup happens if your module is unloaded,
248 * you are responsible here.) If an error occurs, %NULL will be returned.
249 *
250 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
251 * returned. It is not wise to check for this value, but rather, check for
252 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
253 * code.
254 */
255struct dentry *debugfs_create_u64(const char *name, mode_t mode,
256 struct dentry *parent, u64 *value)
257{
258 /* if there are no write bits set, make read only */
259 if (!(mode & S_IWUGO))
260 return debugfs_create_file(name, mode, parent, value, &fops_u64_ro);
261 /* if there are no read bits set, make write only */
262 if (!(mode & S_IRUGO))
263 return debugfs_create_file(name, mode, parent, value, &fops_u64_wo);
264
265 return debugfs_create_file(name, mode, parent, value, &fops_u64);
266}
267EXPORT_SYMBOL_GPL(debugfs_create_u64);
268
269DEFINE_SIMPLE_ATTRIBUTE(fops_x8, debugfs_u8_get, debugfs_u8_set, "0x%02llx\n");
270DEFINE_SIMPLE_ATTRIBUTE(fops_x8_ro, debugfs_u8_get, NULL, "0x%02llx\n");
271DEFINE_SIMPLE_ATTRIBUTE(fops_x8_wo, NULL, debugfs_u8_set, "0x%02llx\n");
272
273DEFINE_SIMPLE_ATTRIBUTE(fops_x16, debugfs_u16_get, debugfs_u16_set, "0x%04llx\n");
274DEFINE_SIMPLE_ATTRIBUTE(fops_x16_ro, debugfs_u16_get, NULL, "0x%04llx\n");
275DEFINE_SIMPLE_ATTRIBUTE(fops_x16_wo, NULL, debugfs_u16_set, "0x%04llx\n");
276
277DEFINE_SIMPLE_ATTRIBUTE(fops_x32, debugfs_u32_get, debugfs_u32_set, "0x%08llx\n");
278DEFINE_SIMPLE_ATTRIBUTE(fops_x32_ro, debugfs_u32_get, NULL, "0x%08llx\n");
279DEFINE_SIMPLE_ATTRIBUTE(fops_x32_wo, NULL, debugfs_u32_set, "0x%08llx\n");
280
281DEFINE_SIMPLE_ATTRIBUTE(fops_x64, debugfs_u64_get, debugfs_u64_set, "0x%016llx\n");
282
283/*
284 * debugfs_create_x{8,16,32,64} - create a debugfs file that is used to read and write an unsigned {8,16,32,64}-bit value
285 *
286 * These functions are exactly the same as the above functions (but use a hex
287 * output for the decimal challenged). For details look at the above unsigned
288 * decimal functions.
289 */
290
291/**
292 * debugfs_create_x8 - create a debugfs file that is used to read and write an unsigned 8-bit value
293 * @name: a pointer to a string containing the name of the file to create.
294 * @mode: the permission that the file should have
295 * @parent: a pointer to the parent dentry for this file. This should be a
296 * directory dentry if set. If this parameter is %NULL, then the
297 * file will be created in the root of the debugfs filesystem.
298 * @value: a pointer to the variable that the file should read to and write
299 * from.
300 */
301struct dentry *debugfs_create_x8(const char *name, mode_t mode,
302 struct dentry *parent, u8 *value)
303{
304 /* if there are no write bits set, make read only */
305 if (!(mode & S_IWUGO))
306 return debugfs_create_file(name, mode, parent, value, &fops_x8_ro);
307 /* if there are no read bits set, make write only */
308 if (!(mode & S_IRUGO))
309 return debugfs_create_file(name, mode, parent, value, &fops_x8_wo);
310
311 return debugfs_create_file(name, mode, parent, value, &fops_x8);
312}
313EXPORT_SYMBOL_GPL(debugfs_create_x8);
314
315/**
316 * debugfs_create_x16 - create a debugfs file that is used to read and write an unsigned 16-bit value
317 * @name: a pointer to a string containing the name of the file to create.
318 * @mode: the permission that the file should have
319 * @parent: a pointer to the parent dentry for this file. This should be a
320 * directory dentry if set. If this parameter is %NULL, then the
321 * file will be created in the root of the debugfs filesystem.
322 * @value: a pointer to the variable that the file should read to and write
323 * from.
324 */
325struct dentry *debugfs_create_x16(const char *name, mode_t mode,
326 struct dentry *parent, u16 *value)
327{
328 /* if there are no write bits set, make read only */
329 if (!(mode & S_IWUGO))
330 return debugfs_create_file(name, mode, parent, value, &fops_x16_ro);
331 /* if there are no read bits set, make write only */
332 if (!(mode & S_IRUGO))
333 return debugfs_create_file(name, mode, parent, value, &fops_x16_wo);
334
335 return debugfs_create_file(name, mode, parent, value, &fops_x16);
336}
337EXPORT_SYMBOL_GPL(debugfs_create_x16);
338
339/**
340 * debugfs_create_x32 - create a debugfs file that is used to read and write an unsigned 32-bit value
341 * @name: a pointer to a string containing the name of the file to create.
342 * @mode: the permission that the file should have
343 * @parent: a pointer to the parent dentry for this file. This should be a
344 * directory dentry if set. If this parameter is %NULL, then the
345 * file will be created in the root of the debugfs filesystem.
346 * @value: a pointer to the variable that the file should read to and write
347 * from.
348 */
349struct dentry *debugfs_create_x32(const char *name, mode_t mode,
350 struct dentry *parent, u32 *value)
351{
352 /* if there are no write bits set, make read only */
353 if (!(mode & S_IWUGO))
354 return debugfs_create_file(name, mode, parent, value, &fops_x32_ro);
355 /* if there are no read bits set, make write only */
356 if (!(mode & S_IRUGO))
357 return debugfs_create_file(name, mode, parent, value, &fops_x32_wo);
358
359 return debugfs_create_file(name, mode, parent, value, &fops_x32);
360}
361EXPORT_SYMBOL_GPL(debugfs_create_x32);
362
363/**
364 * debugfs_create_x64 - create a debugfs file that is used to read and write an unsigned 64-bit value
365 * @name: a pointer to a string containing the name of the file to create.
366 * @mode: the permission that the file should have
367 * @parent: a pointer to the parent dentry for this file. This should be a
368 * directory dentry if set. If this parameter is %NULL, then the
369 * file will be created in the root of the debugfs filesystem.
370 * @value: a pointer to the variable that the file should read to and write
371 * from.
372 */
373struct dentry *debugfs_create_x64(const char *name, mode_t mode,
374 struct dentry *parent, u64 *value)
375{
376 return debugfs_create_file(name, mode, parent, value, &fops_x64);
377}
378EXPORT_SYMBOL_GPL(debugfs_create_x64);
379
380
381static int debugfs_size_t_set(void *data, u64 val)
382{
383 *(size_t *)data = val;
384 return 0;
385}
386static int debugfs_size_t_get(void *data, u64 *val)
387{
388 *val = *(size_t *)data;
389 return 0;
390}
391DEFINE_SIMPLE_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set,
392 "%llu\n"); /* %llu and %zu are more or less the same */
393
394/**
395 * debugfs_create_size_t - create a debugfs file that is used to read and write an size_t value
396 * @name: a pointer to a string containing the name of the file to create.
397 * @mode: the permission that the file should have
398 * @parent: a pointer to the parent dentry for this file. This should be a
399 * directory dentry if set. If this parameter is %NULL, then the
400 * file will be created in the root of the debugfs filesystem.
401 * @value: a pointer to the variable that the file should read to and write
402 * from.
403 */
404struct dentry *debugfs_create_size_t(const char *name, mode_t mode,
405 struct dentry *parent, size_t *value)
406{
407 return debugfs_create_file(name, mode, parent, value, &fops_size_t);
408}
409EXPORT_SYMBOL_GPL(debugfs_create_size_t);
410
411
412static ssize_t read_file_bool(struct file *file, char __user *user_buf,
413 size_t count, loff_t *ppos)
414{
415 char buf[3];
416 u32 *val = file->private_data;
417
418 if (*val)
419 buf[0] = 'Y';
420 else
421 buf[0] = 'N';
422 buf[1] = '\n';
423 buf[2] = 0x00;
424 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
425}
426
427static ssize_t write_file_bool(struct file *file, const char __user *user_buf,
428 size_t count, loff_t *ppos)
429{
430 char buf[32];
431 size_t buf_size;
432 bool bv;
433 u32 *val = file->private_data;
434
435 buf_size = min(count, (sizeof(buf)-1));
436 if (copy_from_user(buf, user_buf, buf_size))
437 return -EFAULT;
438
439 if (strtobool(buf, &bv) == 0)
440 *val = bv;
441
442 return count;
443}
444
445static const struct file_operations fops_bool = {
446 .read = read_file_bool,
447 .write = write_file_bool,
448 .open = default_open,
449 .llseek = default_llseek,
450};
451
452/**
453 * debugfs_create_bool - create a debugfs file that is used to read and write a boolean value
454 * @name: a pointer to a string containing the name of the file to create.
455 * @mode: the permission that the file should have
456 * @parent: a pointer to the parent dentry for this file. This should be a
457 * directory dentry if set. If this parameter is %NULL, then the
458 * file will be created in the root of the debugfs filesystem.
459 * @value: a pointer to the variable that the file should read to and write
460 * from.
461 *
462 * This function creates a file in debugfs with the given name that
463 * contains the value of the variable @value. If the @mode variable is so
464 * set, it can be read from, and written to.
465 *
466 * This function will return a pointer to a dentry if it succeeds. This
467 * pointer must be passed to the debugfs_remove() function when the file is
468 * to be removed (no automatic cleanup happens if your module is unloaded,
469 * you are responsible here.) If an error occurs, %NULL will be returned.
470 *
471 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
472 * returned. It is not wise to check for this value, but rather, check for
473 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
474 * code.
475 */
476struct dentry *debugfs_create_bool(const char *name, mode_t mode,
477 struct dentry *parent, u32 *value)
478{
479 return debugfs_create_file(name, mode, parent, value, &fops_bool);
480}
481EXPORT_SYMBOL_GPL(debugfs_create_bool);
482
483static ssize_t read_file_blob(struct file *file, char __user *user_buf,
484 size_t count, loff_t *ppos)
485{
486 struct debugfs_blob_wrapper *blob = file->private_data;
487 return simple_read_from_buffer(user_buf, count, ppos, blob->data,
488 blob->size);
489}
490
491static const struct file_operations fops_blob = {
492 .read = read_file_blob,
493 .open = default_open,
494 .llseek = default_llseek,
495};
496
497/**
498 * debugfs_create_blob - create a debugfs file that is used to read a binary blob
499 * @name: a pointer to a string containing the name of the file to create.
500 * @mode: the permission that the file should have
501 * @parent: a pointer to the parent dentry for this file. This should be a
502 * directory dentry if set. If this parameter is %NULL, then the
503 * file will be created in the root of the debugfs filesystem.
504 * @blob: a pointer to a struct debugfs_blob_wrapper which contains a pointer
505 * to the blob data and the size of the data.
506 *
507 * This function creates a file in debugfs with the given name that exports
508 * @blob->data as a binary blob. If the @mode variable is so set it can be
509 * read from. Writing is not supported.
510 *
511 * This function will return a pointer to a dentry if it succeeds. This
512 * pointer must be passed to the debugfs_remove() function when the file is
513 * to be removed (no automatic cleanup happens if your module is unloaded,
514 * you are responsible here.) If an error occurs, %NULL will be returned.
515 *
516 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
517 * returned. It is not wise to check for this value, but rather, check for
518 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
519 * code.
520 */
521struct dentry *debugfs_create_blob(const char *name, mode_t mode,
522 struct dentry *parent,
523 struct debugfs_blob_wrapper *blob)
524{
525 return debugfs_create_file(name, mode, parent, blob, &fops_blob);
526}
527EXPORT_SYMBOL_GPL(debugfs_create_blob);
1/*
2 * file.c - part of debugfs, a tiny little debug file system
3 *
4 * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
5 * Copyright (C) 2004 IBM Inc.
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License version
9 * 2 as published by the Free Software Foundation.
10 *
11 * debugfs is for people to use instead of /proc or /sys.
12 * See Documentation/DocBook/filesystems for more details.
13 *
14 */
15
16#include <linux/module.h>
17#include <linux/fs.h>
18#include <linux/seq_file.h>
19#include <linux/pagemap.h>
20#include <linux/namei.h>
21#include <linux/debugfs.h>
22#include <linux/io.h>
23#include <linux/slab.h>
24
25static ssize_t default_read_file(struct file *file, char __user *buf,
26 size_t count, loff_t *ppos)
27{
28 return 0;
29}
30
31static ssize_t default_write_file(struct file *file, const char __user *buf,
32 size_t count, loff_t *ppos)
33{
34 return count;
35}
36
37const struct file_operations debugfs_file_operations = {
38 .read = default_read_file,
39 .write = default_write_file,
40 .open = simple_open,
41 .llseek = noop_llseek,
42};
43
44static void *debugfs_follow_link(struct dentry *dentry, struct nameidata *nd)
45{
46 nd_set_link(nd, dentry->d_inode->i_private);
47 return NULL;
48}
49
50const struct inode_operations debugfs_link_operations = {
51 .readlink = generic_readlink,
52 .follow_link = debugfs_follow_link,
53};
54
55static int debugfs_u8_set(void *data, u64 val)
56{
57 *(u8 *)data = val;
58 return 0;
59}
60static int debugfs_u8_get(void *data, u64 *val)
61{
62 *val = *(u8 *)data;
63 return 0;
64}
65DEFINE_SIMPLE_ATTRIBUTE(fops_u8, debugfs_u8_get, debugfs_u8_set, "%llu\n");
66DEFINE_SIMPLE_ATTRIBUTE(fops_u8_ro, debugfs_u8_get, NULL, "%llu\n");
67DEFINE_SIMPLE_ATTRIBUTE(fops_u8_wo, NULL, debugfs_u8_set, "%llu\n");
68
69/**
70 * debugfs_create_u8 - create a debugfs file that is used to read and write an unsigned 8-bit value
71 * @name: a pointer to a string containing the name of the file to create.
72 * @mode: the permission that the file should have
73 * @parent: a pointer to the parent dentry for this file. This should be a
74 * directory dentry if set. If this parameter is %NULL, then the
75 * file will be created in the root of the debugfs filesystem.
76 * @value: a pointer to the variable that the file should read to and write
77 * from.
78 *
79 * This function creates a file in debugfs with the given name that
80 * contains the value of the variable @value. If the @mode variable is so
81 * set, it can be read from, and written to.
82 *
83 * This function will return a pointer to a dentry if it succeeds. This
84 * pointer must be passed to the debugfs_remove() function when the file is
85 * to be removed (no automatic cleanup happens if your module is unloaded,
86 * you are responsible here.) If an error occurs, %NULL will be returned.
87 *
88 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
89 * returned. It is not wise to check for this value, but rather, check for
90 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
91 * code.
92 */
93struct dentry *debugfs_create_u8(const char *name, umode_t mode,
94 struct dentry *parent, u8 *value)
95{
96 /* if there are no write bits set, make read only */
97 if (!(mode & S_IWUGO))
98 return debugfs_create_file(name, mode, parent, value, &fops_u8_ro);
99 /* if there are no read bits set, make write only */
100 if (!(mode & S_IRUGO))
101 return debugfs_create_file(name, mode, parent, value, &fops_u8_wo);
102
103 return debugfs_create_file(name, mode, parent, value, &fops_u8);
104}
105EXPORT_SYMBOL_GPL(debugfs_create_u8);
106
107static int debugfs_u16_set(void *data, u64 val)
108{
109 *(u16 *)data = val;
110 return 0;
111}
112static int debugfs_u16_get(void *data, u64 *val)
113{
114 *val = *(u16 *)data;
115 return 0;
116}
117DEFINE_SIMPLE_ATTRIBUTE(fops_u16, debugfs_u16_get, debugfs_u16_set, "%llu\n");
118DEFINE_SIMPLE_ATTRIBUTE(fops_u16_ro, debugfs_u16_get, NULL, "%llu\n");
119DEFINE_SIMPLE_ATTRIBUTE(fops_u16_wo, NULL, debugfs_u16_set, "%llu\n");
120
121/**
122 * debugfs_create_u16 - create a debugfs file that is used to read and write an unsigned 16-bit value
123 * @name: a pointer to a string containing the name of the file to create.
124 * @mode: the permission that the file should have
125 * @parent: a pointer to the parent dentry for this file. This should be a
126 * directory dentry if set. If this parameter is %NULL, then the
127 * file will be created in the root of the debugfs filesystem.
128 * @value: a pointer to the variable that the file should read to and write
129 * from.
130 *
131 * This function creates a file in debugfs with the given name that
132 * contains the value of the variable @value. If the @mode variable is so
133 * set, it can be read from, and written to.
134 *
135 * This function will return a pointer to a dentry if it succeeds. This
136 * pointer must be passed to the debugfs_remove() function when the file is
137 * to be removed (no automatic cleanup happens if your module is unloaded,
138 * you are responsible here.) If an error occurs, %NULL will be returned.
139 *
140 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
141 * returned. It is not wise to check for this value, but rather, check for
142 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
143 * code.
144 */
145struct dentry *debugfs_create_u16(const char *name, umode_t mode,
146 struct dentry *parent, u16 *value)
147{
148 /* if there are no write bits set, make read only */
149 if (!(mode & S_IWUGO))
150 return debugfs_create_file(name, mode, parent, value, &fops_u16_ro);
151 /* if there are no read bits set, make write only */
152 if (!(mode & S_IRUGO))
153 return debugfs_create_file(name, mode, parent, value, &fops_u16_wo);
154
155 return debugfs_create_file(name, mode, parent, value, &fops_u16);
156}
157EXPORT_SYMBOL_GPL(debugfs_create_u16);
158
159static int debugfs_u32_set(void *data, u64 val)
160{
161 *(u32 *)data = val;
162 return 0;
163}
164static int debugfs_u32_get(void *data, u64 *val)
165{
166 *val = *(u32 *)data;
167 return 0;
168}
169DEFINE_SIMPLE_ATTRIBUTE(fops_u32, debugfs_u32_get, debugfs_u32_set, "%llu\n");
170DEFINE_SIMPLE_ATTRIBUTE(fops_u32_ro, debugfs_u32_get, NULL, "%llu\n");
171DEFINE_SIMPLE_ATTRIBUTE(fops_u32_wo, NULL, debugfs_u32_set, "%llu\n");
172
173/**
174 * debugfs_create_u32 - create a debugfs file that is used to read and write an unsigned 32-bit value
175 * @name: a pointer to a string containing the name of the file to create.
176 * @mode: the permission that the file should have
177 * @parent: a pointer to the parent dentry for this file. This should be a
178 * directory dentry if set. If this parameter is %NULL, then the
179 * file will be created in the root of the debugfs filesystem.
180 * @value: a pointer to the variable that the file should read to and write
181 * from.
182 *
183 * This function creates a file in debugfs with the given name that
184 * contains the value of the variable @value. If the @mode variable is so
185 * set, it can be read from, and written to.
186 *
187 * This function will return a pointer to a dentry if it succeeds. This
188 * pointer must be passed to the debugfs_remove() function when the file is
189 * to be removed (no automatic cleanup happens if your module is unloaded,
190 * you are responsible here.) If an error occurs, %NULL will be returned.
191 *
192 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
193 * returned. It is not wise to check for this value, but rather, check for
194 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
195 * code.
196 */
197struct dentry *debugfs_create_u32(const char *name, umode_t mode,
198 struct dentry *parent, u32 *value)
199{
200 /* if there are no write bits set, make read only */
201 if (!(mode & S_IWUGO))
202 return debugfs_create_file(name, mode, parent, value, &fops_u32_ro);
203 /* if there are no read bits set, make write only */
204 if (!(mode & S_IRUGO))
205 return debugfs_create_file(name, mode, parent, value, &fops_u32_wo);
206
207 return debugfs_create_file(name, mode, parent, value, &fops_u32);
208}
209EXPORT_SYMBOL_GPL(debugfs_create_u32);
210
211static int debugfs_u64_set(void *data, u64 val)
212{
213 *(u64 *)data = val;
214 return 0;
215}
216
217static int debugfs_u64_get(void *data, u64 *val)
218{
219 *val = *(u64 *)data;
220 return 0;
221}
222DEFINE_SIMPLE_ATTRIBUTE(fops_u64, debugfs_u64_get, debugfs_u64_set, "%llu\n");
223DEFINE_SIMPLE_ATTRIBUTE(fops_u64_ro, debugfs_u64_get, NULL, "%llu\n");
224DEFINE_SIMPLE_ATTRIBUTE(fops_u64_wo, NULL, debugfs_u64_set, "%llu\n");
225
226/**
227 * debugfs_create_u64 - create a debugfs file that is used to read and write an unsigned 64-bit value
228 * @name: a pointer to a string containing the name of the file to create.
229 * @mode: the permission that the file should have
230 * @parent: a pointer to the parent dentry for this file. This should be a
231 * directory dentry if set. If this parameter is %NULL, then the
232 * file will be created in the root of the debugfs filesystem.
233 * @value: a pointer to the variable that the file should read to and write
234 * from.
235 *
236 * This function creates a file in debugfs with the given name that
237 * contains the value of the variable @value. If the @mode variable is so
238 * set, it can be read from, and written to.
239 *
240 * This function will return a pointer to a dentry if it succeeds. This
241 * pointer must be passed to the debugfs_remove() function when the file is
242 * to be removed (no automatic cleanup happens if your module is unloaded,
243 * you are responsible here.) If an error occurs, %NULL will be returned.
244 *
245 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
246 * returned. It is not wise to check for this value, but rather, check for
247 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
248 * code.
249 */
250struct dentry *debugfs_create_u64(const char *name, umode_t mode,
251 struct dentry *parent, u64 *value)
252{
253 /* if there are no write bits set, make read only */
254 if (!(mode & S_IWUGO))
255 return debugfs_create_file(name, mode, parent, value, &fops_u64_ro);
256 /* if there are no read bits set, make write only */
257 if (!(mode & S_IRUGO))
258 return debugfs_create_file(name, mode, parent, value, &fops_u64_wo);
259
260 return debugfs_create_file(name, mode, parent, value, &fops_u64);
261}
262EXPORT_SYMBOL_GPL(debugfs_create_u64);
263
264DEFINE_SIMPLE_ATTRIBUTE(fops_x8, debugfs_u8_get, debugfs_u8_set, "0x%02llx\n");
265DEFINE_SIMPLE_ATTRIBUTE(fops_x8_ro, debugfs_u8_get, NULL, "0x%02llx\n");
266DEFINE_SIMPLE_ATTRIBUTE(fops_x8_wo, NULL, debugfs_u8_set, "0x%02llx\n");
267
268DEFINE_SIMPLE_ATTRIBUTE(fops_x16, debugfs_u16_get, debugfs_u16_set, "0x%04llx\n");
269DEFINE_SIMPLE_ATTRIBUTE(fops_x16_ro, debugfs_u16_get, NULL, "0x%04llx\n");
270DEFINE_SIMPLE_ATTRIBUTE(fops_x16_wo, NULL, debugfs_u16_set, "0x%04llx\n");
271
272DEFINE_SIMPLE_ATTRIBUTE(fops_x32, debugfs_u32_get, debugfs_u32_set, "0x%08llx\n");
273DEFINE_SIMPLE_ATTRIBUTE(fops_x32_ro, debugfs_u32_get, NULL, "0x%08llx\n");
274DEFINE_SIMPLE_ATTRIBUTE(fops_x32_wo, NULL, debugfs_u32_set, "0x%08llx\n");
275
276DEFINE_SIMPLE_ATTRIBUTE(fops_x64, debugfs_u64_get, debugfs_u64_set, "0x%016llx\n");
277
278/*
279 * debugfs_create_x{8,16,32,64} - create a debugfs file that is used to read and write an unsigned {8,16,32,64}-bit value
280 *
281 * These functions are exactly the same as the above functions (but use a hex
282 * output for the decimal challenged). For details look at the above unsigned
283 * decimal functions.
284 */
285
286/**
287 * debugfs_create_x8 - create a debugfs file that is used to read and write an unsigned 8-bit value
288 * @name: a pointer to a string containing the name of the file to create.
289 * @mode: the permission that the file should have
290 * @parent: a pointer to the parent dentry for this file. This should be a
291 * directory dentry if set. If this parameter is %NULL, then the
292 * file will be created in the root of the debugfs filesystem.
293 * @value: a pointer to the variable that the file should read to and write
294 * from.
295 */
296struct dentry *debugfs_create_x8(const char *name, umode_t mode,
297 struct dentry *parent, u8 *value)
298{
299 /* if there are no write bits set, make read only */
300 if (!(mode & S_IWUGO))
301 return debugfs_create_file(name, mode, parent, value, &fops_x8_ro);
302 /* if there are no read bits set, make write only */
303 if (!(mode & S_IRUGO))
304 return debugfs_create_file(name, mode, parent, value, &fops_x8_wo);
305
306 return debugfs_create_file(name, mode, parent, value, &fops_x8);
307}
308EXPORT_SYMBOL_GPL(debugfs_create_x8);
309
310/**
311 * debugfs_create_x16 - create a debugfs file that is used to read and write an unsigned 16-bit value
312 * @name: a pointer to a string containing the name of the file to create.
313 * @mode: the permission that the file should have
314 * @parent: a pointer to the parent dentry for this file. This should be a
315 * directory dentry if set. If this parameter is %NULL, then the
316 * file will be created in the root of the debugfs filesystem.
317 * @value: a pointer to the variable that the file should read to and write
318 * from.
319 */
320struct dentry *debugfs_create_x16(const char *name, umode_t mode,
321 struct dentry *parent, u16 *value)
322{
323 /* if there are no write bits set, make read only */
324 if (!(mode & S_IWUGO))
325 return debugfs_create_file(name, mode, parent, value, &fops_x16_ro);
326 /* if there are no read bits set, make write only */
327 if (!(mode & S_IRUGO))
328 return debugfs_create_file(name, mode, parent, value, &fops_x16_wo);
329
330 return debugfs_create_file(name, mode, parent, value, &fops_x16);
331}
332EXPORT_SYMBOL_GPL(debugfs_create_x16);
333
334/**
335 * debugfs_create_x32 - create a debugfs file that is used to read and write an unsigned 32-bit value
336 * @name: a pointer to a string containing the name of the file to create.
337 * @mode: the permission that the file should have
338 * @parent: a pointer to the parent dentry for this file. This should be a
339 * directory dentry if set. If this parameter is %NULL, then the
340 * file will be created in the root of the debugfs filesystem.
341 * @value: a pointer to the variable that the file should read to and write
342 * from.
343 */
344struct dentry *debugfs_create_x32(const char *name, umode_t mode,
345 struct dentry *parent, u32 *value)
346{
347 /* if there are no write bits set, make read only */
348 if (!(mode & S_IWUGO))
349 return debugfs_create_file(name, mode, parent, value, &fops_x32_ro);
350 /* if there are no read bits set, make write only */
351 if (!(mode & S_IRUGO))
352 return debugfs_create_file(name, mode, parent, value, &fops_x32_wo);
353
354 return debugfs_create_file(name, mode, parent, value, &fops_x32);
355}
356EXPORT_SYMBOL_GPL(debugfs_create_x32);
357
358/**
359 * debugfs_create_x64 - create a debugfs file that is used to read and write an unsigned 64-bit value
360 * @name: a pointer to a string containing the name of the file to create.
361 * @mode: the permission that the file should have
362 * @parent: a pointer to the parent dentry for this file. This should be a
363 * directory dentry if set. If this parameter is %NULL, then the
364 * file will be created in the root of the debugfs filesystem.
365 * @value: a pointer to the variable that the file should read to and write
366 * from.
367 */
368struct dentry *debugfs_create_x64(const char *name, umode_t mode,
369 struct dentry *parent, u64 *value)
370{
371 return debugfs_create_file(name, mode, parent, value, &fops_x64);
372}
373EXPORT_SYMBOL_GPL(debugfs_create_x64);
374
375
376static int debugfs_size_t_set(void *data, u64 val)
377{
378 *(size_t *)data = val;
379 return 0;
380}
381static int debugfs_size_t_get(void *data, u64 *val)
382{
383 *val = *(size_t *)data;
384 return 0;
385}
386DEFINE_SIMPLE_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set,
387 "%llu\n"); /* %llu and %zu are more or less the same */
388
389/**
390 * debugfs_create_size_t - create a debugfs file that is used to read and write an size_t value
391 * @name: a pointer to a string containing the name of the file to create.
392 * @mode: the permission that the file should have
393 * @parent: a pointer to the parent dentry for this file. This should be a
394 * directory dentry if set. If this parameter is %NULL, then the
395 * file will be created in the root of the debugfs filesystem.
396 * @value: a pointer to the variable that the file should read to and write
397 * from.
398 */
399struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
400 struct dentry *parent, size_t *value)
401{
402 return debugfs_create_file(name, mode, parent, value, &fops_size_t);
403}
404EXPORT_SYMBOL_GPL(debugfs_create_size_t);
405
406
407static ssize_t read_file_bool(struct file *file, char __user *user_buf,
408 size_t count, loff_t *ppos)
409{
410 char buf[3];
411 u32 *val = file->private_data;
412
413 if (*val)
414 buf[0] = 'Y';
415 else
416 buf[0] = 'N';
417 buf[1] = '\n';
418 buf[2] = 0x00;
419 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
420}
421
422static ssize_t write_file_bool(struct file *file, const char __user *user_buf,
423 size_t count, loff_t *ppos)
424{
425 char buf[32];
426 size_t buf_size;
427 bool bv;
428 u32 *val = file->private_data;
429
430 buf_size = min(count, (sizeof(buf)-1));
431 if (copy_from_user(buf, user_buf, buf_size))
432 return -EFAULT;
433
434 if (strtobool(buf, &bv) == 0)
435 *val = bv;
436
437 return count;
438}
439
440static const struct file_operations fops_bool = {
441 .read = read_file_bool,
442 .write = write_file_bool,
443 .open = simple_open,
444 .llseek = default_llseek,
445};
446
447/**
448 * debugfs_create_bool - create a debugfs file that is used to read and write a boolean value
449 * @name: a pointer to a string containing the name of the file to create.
450 * @mode: the permission that the file should have
451 * @parent: a pointer to the parent dentry for this file. This should be a
452 * directory dentry if set. If this parameter is %NULL, then the
453 * file will be created in the root of the debugfs filesystem.
454 * @value: a pointer to the variable that the file should read to and write
455 * from.
456 *
457 * This function creates a file in debugfs with the given name that
458 * contains the value of the variable @value. If the @mode variable is so
459 * set, it can be read from, and written to.
460 *
461 * This function will return a pointer to a dentry if it succeeds. This
462 * pointer must be passed to the debugfs_remove() function when the file is
463 * to be removed (no automatic cleanup happens if your module is unloaded,
464 * you are responsible here.) If an error occurs, %NULL will be returned.
465 *
466 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
467 * returned. It is not wise to check for this value, but rather, check for
468 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
469 * code.
470 */
471struct dentry *debugfs_create_bool(const char *name, umode_t mode,
472 struct dentry *parent, u32 *value)
473{
474 return debugfs_create_file(name, mode, parent, value, &fops_bool);
475}
476EXPORT_SYMBOL_GPL(debugfs_create_bool);
477
478static ssize_t read_file_blob(struct file *file, char __user *user_buf,
479 size_t count, loff_t *ppos)
480{
481 struct debugfs_blob_wrapper *blob = file->private_data;
482 return simple_read_from_buffer(user_buf, count, ppos, blob->data,
483 blob->size);
484}
485
486static const struct file_operations fops_blob = {
487 .read = read_file_blob,
488 .open = simple_open,
489 .llseek = default_llseek,
490};
491
492/**
493 * debugfs_create_blob - create a debugfs file that is used to read a binary blob
494 * @name: a pointer to a string containing the name of the file to create.
495 * @mode: the permission that the file should have
496 * @parent: a pointer to the parent dentry for this file. This should be a
497 * directory dentry if set. If this parameter is %NULL, then the
498 * file will be created in the root of the debugfs filesystem.
499 * @blob: a pointer to a struct debugfs_blob_wrapper which contains a pointer
500 * to the blob data and the size of the data.
501 *
502 * This function creates a file in debugfs with the given name that exports
503 * @blob->data as a binary blob. If the @mode variable is so set it can be
504 * read from. Writing is not supported.
505 *
506 * This function will return a pointer to a dentry if it succeeds. This
507 * pointer must be passed to the debugfs_remove() function when the file is
508 * to be removed (no automatic cleanup happens if your module is unloaded,
509 * you are responsible here.) If an error occurs, %NULL will be returned.
510 *
511 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
512 * returned. It is not wise to check for this value, but rather, check for
513 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
514 * code.
515 */
516struct dentry *debugfs_create_blob(const char *name, umode_t mode,
517 struct dentry *parent,
518 struct debugfs_blob_wrapper *blob)
519{
520 return debugfs_create_file(name, mode, parent, blob, &fops_blob);
521}
522EXPORT_SYMBOL_GPL(debugfs_create_blob);
523
524struct array_data {
525 void *array;
526 u32 elements;
527};
528
529static int u32_array_open(struct inode *inode, struct file *file)
530{
531 file->private_data = NULL;
532 return nonseekable_open(inode, file);
533}
534
535static size_t format_array(char *buf, size_t bufsize, const char *fmt,
536 u32 *array, u32 array_size)
537{
538 size_t ret = 0;
539 u32 i;
540
541 for (i = 0; i < array_size; i++) {
542 size_t len;
543
544 len = snprintf(buf, bufsize, fmt, array[i]);
545 len++; /* ' ' or '\n' */
546 ret += len;
547
548 if (buf) {
549 buf += len;
550 bufsize -= len;
551 buf[-1] = (i == array_size-1) ? '\n' : ' ';
552 }
553 }
554
555 ret++; /* \0 */
556 if (buf)
557 *buf = '\0';
558
559 return ret;
560}
561
562static char *format_array_alloc(const char *fmt, u32 *array,
563 u32 array_size)
564{
565 size_t len = format_array(NULL, 0, fmt, array, array_size);
566 char *ret;
567
568 ret = kmalloc(len, GFP_KERNEL);
569 if (ret == NULL)
570 return NULL;
571
572 format_array(ret, len, fmt, array, array_size);
573 return ret;
574}
575
576static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
577 loff_t *ppos)
578{
579 struct inode *inode = file->f_path.dentry->d_inode;
580 struct array_data *data = inode->i_private;
581 size_t size;
582
583 if (*ppos == 0) {
584 if (file->private_data) {
585 kfree(file->private_data);
586 file->private_data = NULL;
587 }
588
589 file->private_data = format_array_alloc("%u", data->array,
590 data->elements);
591 }
592
593 size = 0;
594 if (file->private_data)
595 size = strlen(file->private_data);
596
597 return simple_read_from_buffer(buf, len, ppos,
598 file->private_data, size);
599}
600
601static int u32_array_release(struct inode *inode, struct file *file)
602{
603 kfree(file->private_data);
604
605 return 0;
606}
607
608static const struct file_operations u32_array_fops = {
609 .owner = THIS_MODULE,
610 .open = u32_array_open,
611 .release = u32_array_release,
612 .read = u32_array_read,
613 .llseek = no_llseek,
614};
615
616/**
617 * debugfs_create_u32_array - create a debugfs file that is used to read u32
618 * array.
619 * @name: a pointer to a string containing the name of the file to create.
620 * @mode: the permission that the file should have.
621 * @parent: a pointer to the parent dentry for this file. This should be a
622 * directory dentry if set. If this parameter is %NULL, then the
623 * file will be created in the root of the debugfs filesystem.
624 * @array: u32 array that provides data.
625 * @elements: total number of elements in the array.
626 *
627 * This function creates a file in debugfs with the given name that exports
628 * @array as data. If the @mode variable is so set it can be read from.
629 * Writing is not supported. Seek within the file is also not supported.
630 * Once array is created its size can not be changed.
631 *
632 * The function returns a pointer to dentry on success. If debugfs is not
633 * enabled in the kernel, the value -%ENODEV will be returned.
634 */
635struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
636 struct dentry *parent,
637 u32 *array, u32 elements)
638{
639 struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL);
640
641 if (data == NULL)
642 return NULL;
643
644 data->array = array;
645 data->elements = elements;
646
647 return debugfs_create_file(name, mode, parent, data, &u32_array_fops);
648}
649EXPORT_SYMBOL_GPL(debugfs_create_u32_array);
650
651#ifdef CONFIG_HAS_IOMEM
652
653/*
654 * The regset32 stuff is used to print 32-bit registers using the
655 * seq_file utilities. We offer printing a register set in an already-opened
656 * sequential file or create a debugfs file that only prints a regset32.
657 */
658
659/**
660 * debugfs_print_regs32 - use seq_print to describe a set of registers
661 * @s: the seq_file structure being used to generate output
662 * @regs: an array if struct debugfs_reg32 structures
663 * @nregs: the length of the above array
664 * @base: the base address to be used in reading the registers
665 * @prefix: a string to be prefixed to every output line
666 *
667 * This function outputs a text block describing the current values of
668 * some 32-bit hardware registers. It is meant to be used within debugfs
669 * files based on seq_file that need to show registers, intermixed with other
670 * information. The prefix argument may be used to specify a leading string,
671 * because some peripherals have several blocks of identical registers,
672 * for example configuration of dma channels
673 */
674int debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
675 int nregs, void __iomem *base, char *prefix)
676{
677 int i, ret = 0;
678
679 for (i = 0; i < nregs; i++, regs++) {
680 if (prefix)
681 ret += seq_printf(s, "%s", prefix);
682 ret += seq_printf(s, "%s = 0x%08x\n", regs->name,
683 readl(base + regs->offset));
684 }
685 return ret;
686}
687EXPORT_SYMBOL_GPL(debugfs_print_regs32);
688
689static int debugfs_show_regset32(struct seq_file *s, void *data)
690{
691 struct debugfs_regset32 *regset = s->private;
692
693 debugfs_print_regs32(s, regset->regs, regset->nregs, regset->base, "");
694 return 0;
695}
696
697static int debugfs_open_regset32(struct inode *inode, struct file *file)
698{
699 return single_open(file, debugfs_show_regset32, inode->i_private);
700}
701
702static const struct file_operations fops_regset32 = {
703 .open = debugfs_open_regset32,
704 .read = seq_read,
705 .llseek = seq_lseek,
706 .release = single_release,
707};
708
709/**
710 * debugfs_create_regset32 - create a debugfs file that returns register values
711 * @name: a pointer to a string containing the name of the file to create.
712 * @mode: the permission that the file should have
713 * @parent: a pointer to the parent dentry for this file. This should be a
714 * directory dentry if set. If this parameter is %NULL, then the
715 * file will be created in the root of the debugfs filesystem.
716 * @regset: a pointer to a struct debugfs_regset32, which contains a pointer
717 * to an array of register definitions, the array size and the base
718 * address where the register bank is to be found.
719 *
720 * This function creates a file in debugfs with the given name that reports
721 * the names and values of a set of 32-bit registers. If the @mode variable
722 * is so set it can be read from. Writing is not supported.
723 *
724 * This function will return a pointer to a dentry if it succeeds. This
725 * pointer must be passed to the debugfs_remove() function when the file is
726 * to be removed (no automatic cleanup happens if your module is unloaded,
727 * you are responsible here.) If an error occurs, %NULL will be returned.
728 *
729 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
730 * returned. It is not wise to check for this value, but rather, check for
731 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
732 * code.
733 */
734struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
735 struct dentry *parent,
736 struct debugfs_regset32 *regset)
737{
738 return debugfs_create_file(name, mode, parent, regset, &fops_regset32);
739}
740EXPORT_SYMBOL_GPL(debugfs_create_regset32);
741
742#endif /* CONFIG_HAS_IOMEM */