2 * file.c - part of debugfs, a tiny little debug file system
4 * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
5 * Copyright (C) 2004 IBM Inc.
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.
11 * debugfs is for people to use instead of /proc or /sys.
12 * See Documentation/DocBook/filesystems for more details.
16 #include <linux/module.h>
18 #include <linux/seq_file.h>
19 #include <linux/pagemap.h>
20 #include <linux/debugfs.h>
22 #include <linux/slab.h>
23 #include <linux/atomic.h>
24 #include <linux/device.h>
26 static ssize_t default_read_file(struct file *file, char __user *buf,
27 size_t count, loff_t *ppos)
32 static ssize_t default_write_file(struct file *file, const char __user *buf,
33 size_t count, loff_t *ppos)
38 const struct file_operations debugfs_file_operations = {
39 .read = default_read_file,
40 .write = default_write_file,
42 .llseek = noop_llseek,
45 static struct dentry *debugfs_create_mode(const char *name, umode_t mode,
46 struct dentry *parent, void *value,
47 const struct file_operations *fops,
48 const struct file_operations *fops_ro,
49 const struct file_operations *fops_wo)
51 /* if there are no write bits set, make read only */
52 if (!(mode & S_IWUGO))
53 return debugfs_create_file(name, mode, parent, value, fops_ro);
54 /* if there are no read bits set, make write only */
55 if (!(mode & S_IRUGO))
56 return debugfs_create_file(name, mode, parent, value, fops_wo);
58 return debugfs_create_file(name, mode, parent, value, fops);
61 static int debugfs_u8_set(void *data, u64 val)
66 static int debugfs_u8_get(void *data, u64 *val)
71 DEFINE_SIMPLE_ATTRIBUTE(fops_u8, debugfs_u8_get, debugfs_u8_set, "%llu\n");
72 DEFINE_SIMPLE_ATTRIBUTE(fops_u8_ro, debugfs_u8_get, NULL, "%llu\n");
73 DEFINE_SIMPLE_ATTRIBUTE(fops_u8_wo, NULL, debugfs_u8_set, "%llu\n");
76 * debugfs_create_u8 - create a debugfs file that is used to read and write an unsigned 8-bit value
77 * @name: a pointer to a string containing the name of the file to create.
78 * @mode: the permission that the file should have
79 * @parent: a pointer to the parent dentry for this file. This should be a
80 * directory dentry if set. If this parameter is %NULL, then the
81 * file will be created in the root of the debugfs filesystem.
82 * @value: a pointer to the variable that the file should read to and write
85 * This function creates a file in debugfs with the given name that
86 * contains the value of the variable @value. If the @mode variable is so
87 * set, it can be read from, and written to.
89 * This function will return a pointer to a dentry if it succeeds. This
90 * pointer must be passed to the debugfs_remove() function when the file is
91 * to be removed (no automatic cleanup happens if your module is unloaded,
92 * you are responsible here.) If an error occurs, %NULL will be returned.
94 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
95 * returned. It is not wise to check for this value, but rather, check for
96 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
99 struct dentry *debugfs_create_u8(const char *name, umode_t mode,
100 struct dentry *parent, u8 *value)
102 return debugfs_create_mode(name, mode, parent, value, &fops_u8,
103 &fops_u8_ro, &fops_u8_wo);
105 EXPORT_SYMBOL_GPL(debugfs_create_u8);
107 static int debugfs_u16_set(void *data, u64 val)
112 static int debugfs_u16_get(void *data, u64 *val)
117 DEFINE_SIMPLE_ATTRIBUTE(fops_u16, debugfs_u16_get, debugfs_u16_set, "%llu\n");
118 DEFINE_SIMPLE_ATTRIBUTE(fops_u16_ro, debugfs_u16_get, NULL, "%llu\n");
119 DEFINE_SIMPLE_ATTRIBUTE(fops_u16_wo, NULL, debugfs_u16_set, "%llu\n");
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
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.
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.
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
145 struct dentry *debugfs_create_u16(const char *name, umode_t mode,
146 struct dentry *parent, u16 *value)
148 return debugfs_create_mode(name, mode, parent, value, &fops_u16,
149 &fops_u16_ro, &fops_u16_wo);
151 EXPORT_SYMBOL_GPL(debugfs_create_u16);
153 static int debugfs_u32_set(void *data, u64 val)
158 static int debugfs_u32_get(void *data, u64 *val)
163 DEFINE_SIMPLE_ATTRIBUTE(fops_u32, debugfs_u32_get, debugfs_u32_set, "%llu\n");
164 DEFINE_SIMPLE_ATTRIBUTE(fops_u32_ro, debugfs_u32_get, NULL, "%llu\n");
165 DEFINE_SIMPLE_ATTRIBUTE(fops_u32_wo, NULL, debugfs_u32_set, "%llu\n");
168 * debugfs_create_u32 - create a debugfs file that is used to read and write an unsigned 32-bit value
169 * @name: a pointer to a string containing the name of the file to create.
170 * @mode: the permission that the file should have
171 * @parent: a pointer to the parent dentry for this file. This should be a
172 * directory dentry if set. If this parameter is %NULL, then the
173 * file will be created in the root of the debugfs filesystem.
174 * @value: a pointer to the variable that the file should read to and write
177 * This function creates a file in debugfs with the given name that
178 * contains the value of the variable @value. If the @mode variable is so
179 * set, it can be read from, and written to.
181 * This function will return a pointer to a dentry if it succeeds. This
182 * pointer must be passed to the debugfs_remove() function when the file is
183 * to be removed (no automatic cleanup happens if your module is unloaded,
184 * you are responsible here.) If an error occurs, %NULL will be returned.
186 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
187 * returned. It is not wise to check for this value, but rather, check for
188 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
191 struct dentry *debugfs_create_u32(const char *name, umode_t mode,
192 struct dentry *parent, u32 *value)
194 return debugfs_create_mode(name, mode, parent, value, &fops_u32,
195 &fops_u32_ro, &fops_u32_wo);
197 EXPORT_SYMBOL_GPL(debugfs_create_u32);
199 static int debugfs_u64_set(void *data, u64 val)
205 static int debugfs_u64_get(void *data, u64 *val)
210 DEFINE_SIMPLE_ATTRIBUTE(fops_u64, debugfs_u64_get, debugfs_u64_set, "%llu\n");
211 DEFINE_SIMPLE_ATTRIBUTE(fops_u64_ro, debugfs_u64_get, NULL, "%llu\n");
212 DEFINE_SIMPLE_ATTRIBUTE(fops_u64_wo, NULL, debugfs_u64_set, "%llu\n");
215 * debugfs_create_u64 - create a debugfs file that is used to read and write an unsigned 64-bit value
216 * @name: a pointer to a string containing the name of the file to create.
217 * @mode: the permission that the file should have
218 * @parent: a pointer to the parent dentry for this file. This should be a
219 * directory dentry if set. If this parameter is %NULL, then the
220 * file will be created in the root of the debugfs filesystem.
221 * @value: a pointer to the variable that the file should read to and write
224 * This function creates a file in debugfs with the given name that
225 * contains the value of the variable @value. If the @mode variable is so
226 * set, it can be read from, and written to.
228 * This function will return a pointer to a dentry if it succeeds. This
229 * pointer must be passed to the debugfs_remove() function when the file is
230 * to be removed (no automatic cleanup happens if your module is unloaded,
231 * you are responsible here.) If an error occurs, %NULL will be returned.
233 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
234 * returned. It is not wise to check for this value, but rather, check for
235 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
238 struct dentry *debugfs_create_u64(const char *name, umode_t mode,
239 struct dentry *parent, u64 *value)
241 return debugfs_create_mode(name, mode, parent, value, &fops_u64,
242 &fops_u64_ro, &fops_u64_wo);
244 EXPORT_SYMBOL_GPL(debugfs_create_u64);
246 DEFINE_SIMPLE_ATTRIBUTE(fops_x8, debugfs_u8_get, debugfs_u8_set, "0x%02llx\n");
247 DEFINE_SIMPLE_ATTRIBUTE(fops_x8_ro, debugfs_u8_get, NULL, "0x%02llx\n");
248 DEFINE_SIMPLE_ATTRIBUTE(fops_x8_wo, NULL, debugfs_u8_set, "0x%02llx\n");
250 DEFINE_SIMPLE_ATTRIBUTE(fops_x16, debugfs_u16_get, debugfs_u16_set, "0x%04llx\n");
251 DEFINE_SIMPLE_ATTRIBUTE(fops_x16_ro, debugfs_u16_get, NULL, "0x%04llx\n");
252 DEFINE_SIMPLE_ATTRIBUTE(fops_x16_wo, NULL, debugfs_u16_set, "0x%04llx\n");
254 DEFINE_SIMPLE_ATTRIBUTE(fops_x32, debugfs_u32_get, debugfs_u32_set, "0x%08llx\n");
255 DEFINE_SIMPLE_ATTRIBUTE(fops_x32_ro, debugfs_u32_get, NULL, "0x%08llx\n");
256 DEFINE_SIMPLE_ATTRIBUTE(fops_x32_wo, NULL, debugfs_u32_set, "0x%08llx\n");
258 DEFINE_SIMPLE_ATTRIBUTE(fops_x64, debugfs_u64_get, debugfs_u64_set, "0x%016llx\n");
259 DEFINE_SIMPLE_ATTRIBUTE(fops_x64_ro, debugfs_u64_get, NULL, "0x%016llx\n");
260 DEFINE_SIMPLE_ATTRIBUTE(fops_x64_wo, NULL, debugfs_u64_set, "0x%016llx\n");
263 * 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
265 * These functions are exactly the same as the above functions (but use a hex
266 * output for the decimal challenged). For details look at the above unsigned
271 * debugfs_create_x8 - create a debugfs file that is used to read and write an unsigned 8-bit value
272 * @name: a pointer to a string containing the name of the file to create.
273 * @mode: the permission that the file should have
274 * @parent: a pointer to the parent dentry for this file. This should be a
275 * directory dentry if set. If this parameter is %NULL, then the
276 * file will be created in the root of the debugfs filesystem.
277 * @value: a pointer to the variable that the file should read to and write
280 struct dentry *debugfs_create_x8(const char *name, umode_t mode,
281 struct dentry *parent, u8 *value)
283 return debugfs_create_mode(name, mode, parent, value, &fops_x8,
284 &fops_x8_ro, &fops_x8_wo);
286 EXPORT_SYMBOL_GPL(debugfs_create_x8);
289 * debugfs_create_x16 - create a debugfs file that is used to read and write an unsigned 16-bit value
290 * @name: a pointer to a string containing the name of the file to create.
291 * @mode: the permission that the file should have
292 * @parent: a pointer to the parent dentry for this file. This should be a
293 * directory dentry if set. If this parameter is %NULL, then the
294 * file will be created in the root of the debugfs filesystem.
295 * @value: a pointer to the variable that the file should read to and write
298 struct dentry *debugfs_create_x16(const char *name, umode_t mode,
299 struct dentry *parent, u16 *value)
301 return debugfs_create_mode(name, mode, parent, value, &fops_x16,
302 &fops_x16_ro, &fops_x16_wo);
304 EXPORT_SYMBOL_GPL(debugfs_create_x16);
307 * debugfs_create_x32 - create a debugfs file that is used to read and write an unsigned 32-bit value
308 * @name: a pointer to a string containing the name of the file to create.
309 * @mode: the permission that the file should have
310 * @parent: a pointer to the parent dentry for this file. This should be a
311 * directory dentry if set. If this parameter is %NULL, then the
312 * file will be created in the root of the debugfs filesystem.
313 * @value: a pointer to the variable that the file should read to and write
316 struct dentry *debugfs_create_x32(const char *name, umode_t mode,
317 struct dentry *parent, u32 *value)
319 return debugfs_create_mode(name, mode, parent, value, &fops_x32,
320 &fops_x32_ro, &fops_x32_wo);
322 EXPORT_SYMBOL_GPL(debugfs_create_x32);
325 * debugfs_create_x64 - create a debugfs file that is used to read and write an unsigned 64-bit value
326 * @name: a pointer to a string containing the name of the file to create.
327 * @mode: the permission that the file should have
328 * @parent: a pointer to the parent dentry for this file. This should be a
329 * directory dentry if set. If this parameter is %NULL, then the
330 * file will be created in the root of the debugfs filesystem.
331 * @value: a pointer to the variable that the file should read to and write
334 struct dentry *debugfs_create_x64(const char *name, umode_t mode,
335 struct dentry *parent, u64 *value)
337 return debugfs_create_mode(name, mode, parent, value, &fops_x64,
338 &fops_x64_ro, &fops_x64_wo);
340 EXPORT_SYMBOL_GPL(debugfs_create_x64);
343 static int debugfs_size_t_set(void *data, u64 val)
345 *(size_t *)data = val;
348 static int debugfs_size_t_get(void *data, u64 *val)
350 *val = *(size_t *)data;
353 DEFINE_SIMPLE_ATTRIBUTE(fops_size_t, debugfs_size_t_get, debugfs_size_t_set,
354 "%llu\n"); /* %llu and %zu are more or less the same */
357 * debugfs_create_size_t - create a debugfs file that is used to read and write an size_t value
358 * @name: a pointer to a string containing the name of the file to create.
359 * @mode: the permission that the file should have
360 * @parent: a pointer to the parent dentry for this file. This should be a
361 * directory dentry if set. If this parameter is %NULL, then the
362 * file will be created in the root of the debugfs filesystem.
363 * @value: a pointer to the variable that the file should read to and write
366 struct dentry *debugfs_create_size_t(const char *name, umode_t mode,
367 struct dentry *parent, size_t *value)
369 return debugfs_create_file(name, mode, parent, value, &fops_size_t);
371 EXPORT_SYMBOL_GPL(debugfs_create_size_t);
373 static int debugfs_atomic_t_set(void *data, u64 val)
375 atomic_set((atomic_t *)data, val);
378 static int debugfs_atomic_t_get(void *data, u64 *val)
380 *val = atomic_read((atomic_t *)data);
383 DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t, debugfs_atomic_t_get,
384 debugfs_atomic_t_set, "%lld\n");
385 DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t_ro, debugfs_atomic_t_get, NULL, "%lld\n");
386 DEFINE_SIMPLE_ATTRIBUTE(fops_atomic_t_wo, NULL, debugfs_atomic_t_set, "%lld\n");
389 * debugfs_create_atomic_t - create a debugfs file that is used to read and
390 * write an atomic_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
399 struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode,
400 struct dentry *parent, atomic_t *value)
402 return debugfs_create_mode(name, mode, parent, value, &fops_atomic_t,
403 &fops_atomic_t_ro, &fops_atomic_t_wo);
405 EXPORT_SYMBOL_GPL(debugfs_create_atomic_t);
407 ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
408 size_t count, loff_t *ppos)
411 bool *val = file->private_data;
419 return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
421 EXPORT_SYMBOL_GPL(debugfs_read_file_bool);
423 ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf,
424 size_t count, loff_t *ppos)
429 bool *val = file->private_data;
431 buf_size = min(count, (sizeof(buf)-1));
432 if (copy_from_user(buf, user_buf, buf_size))
435 buf[buf_size] = '\0';
436 if (strtobool(buf, &bv) == 0)
441 EXPORT_SYMBOL_GPL(debugfs_write_file_bool);
443 static const struct file_operations fops_bool = {
444 .read = debugfs_read_file_bool,
445 .write = debugfs_write_file_bool,
447 .llseek = default_llseek,
451 * debugfs_create_bool - create a debugfs file that is used to read and write a boolean value
452 * @name: a pointer to a string containing the name of the file to create.
453 * @mode: the permission that the file should have
454 * @parent: a pointer to the parent dentry for this file. This should be a
455 * directory dentry if set. If this parameter is %NULL, then the
456 * file will be created in the root of the debugfs filesystem.
457 * @value: a pointer to the variable that the file should read to and write
460 * This function creates a file in debugfs with the given name that
461 * contains the value of the variable @value. If the @mode variable is so
462 * set, it can be read from, and written to.
464 * This function will return a pointer to a dentry if it succeeds. This
465 * pointer must be passed to the debugfs_remove() function when the file is
466 * to be removed (no automatic cleanup happens if your module is unloaded,
467 * you are responsible here.) If an error occurs, %NULL will be returned.
469 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
470 * returned. It is not wise to check for this value, but rather, check for
471 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
474 struct dentry *debugfs_create_bool(const char *name, umode_t mode,
475 struct dentry *parent, bool *value)
477 return debugfs_create_file(name, mode, parent, value, &fops_bool);
479 EXPORT_SYMBOL_GPL(debugfs_create_bool);
481 static ssize_t read_file_blob(struct file *file, char __user *user_buf,
482 size_t count, loff_t *ppos)
484 struct debugfs_blob_wrapper *blob = file->private_data;
485 return simple_read_from_buffer(user_buf, count, ppos, blob->data,
489 static const struct file_operations fops_blob = {
490 .read = read_file_blob,
492 .llseek = default_llseek,
496 * debugfs_create_blob - create a debugfs file that is used to read a binary blob
497 * @name: a pointer to a string containing the name of the file to create.
498 * @mode: the permission that the file should have
499 * @parent: a pointer to the parent dentry for this file. This should be a
500 * directory dentry if set. If this parameter is %NULL, then the
501 * file will be created in the root of the debugfs filesystem.
502 * @blob: a pointer to a struct debugfs_blob_wrapper which contains a pointer
503 * to the blob data and the size of the data.
505 * This function creates a file in debugfs with the given name that exports
506 * @blob->data as a binary blob. If the @mode variable is so set it can be
507 * read from. Writing is not supported.
509 * This function will return a pointer to a dentry if it succeeds. This
510 * pointer must be passed to the debugfs_remove() function when the file is
511 * to be removed (no automatic cleanup happens if your module is unloaded,
512 * you are responsible here.) If an error occurs, %NULL will be returned.
514 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
515 * returned. It is not wise to check for this value, but rather, check for
516 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
519 struct dentry *debugfs_create_blob(const char *name, umode_t mode,
520 struct dentry *parent,
521 struct debugfs_blob_wrapper *blob)
523 return debugfs_create_file(name, mode, parent, blob, &fops_blob);
525 EXPORT_SYMBOL_GPL(debugfs_create_blob);
532 static size_t u32_format_array(char *buf, size_t bufsize,
533 u32 *array, int array_size)
537 while (--array_size >= 0) {
539 char term = array_size ? ' ' : '\n';
541 len = snprintf(buf, bufsize, "%u%c", *array++, term);
550 static int u32_array_open(struct inode *inode, struct file *file)
552 struct array_data *data = inode->i_private;
553 int size, elements = data->elements;
558 * - 10 digits + ' '/'\n' = 11 bytes per number
559 * - terminating NUL character
562 buf = kmalloc(size+1, GFP_KERNEL);
567 file->private_data = buf;
568 u32_format_array(buf, size, data->array, data->elements);
570 return nonseekable_open(inode, file);
573 static ssize_t u32_array_read(struct file *file, char __user *buf, size_t len,
576 size_t size = strlen(file->private_data);
578 return simple_read_from_buffer(buf, len, ppos,
579 file->private_data, size);
582 static int u32_array_release(struct inode *inode, struct file *file)
584 kfree(file->private_data);
589 static const struct file_operations u32_array_fops = {
590 .owner = THIS_MODULE,
591 .open = u32_array_open,
592 .release = u32_array_release,
593 .read = u32_array_read,
598 * debugfs_create_u32_array - create a debugfs file that is used to read u32
600 * @name: a pointer to a string containing the name of the file to create.
601 * @mode: the permission that the file should have.
602 * @parent: a pointer to the parent dentry for this file. This should be a
603 * directory dentry if set. If this parameter is %NULL, then the
604 * file will be created in the root of the debugfs filesystem.
605 * @array: u32 array that provides data.
606 * @elements: total number of elements in the array.
608 * This function creates a file in debugfs with the given name that exports
609 * @array as data. If the @mode variable is so set it can be read from.
610 * Writing is not supported. Seek within the file is also not supported.
611 * Once array is created its size can not be changed.
613 * The function returns a pointer to dentry on success. If debugfs is not
614 * enabled in the kernel, the value -%ENODEV will be returned.
616 struct dentry *debugfs_create_u32_array(const char *name, umode_t mode,
617 struct dentry *parent,
618 u32 *array, u32 elements)
620 struct array_data *data = kmalloc(sizeof(*data), GFP_KERNEL);
626 data->elements = elements;
628 return debugfs_create_file(name, mode, parent, data, &u32_array_fops);
630 EXPORT_SYMBOL_GPL(debugfs_create_u32_array);
632 #ifdef CONFIG_HAS_IOMEM
635 * The regset32 stuff is used to print 32-bit registers using the
636 * seq_file utilities. We offer printing a register set in an already-opened
637 * sequential file or create a debugfs file that only prints a regset32.
641 * debugfs_print_regs32 - use seq_print to describe a set of registers
642 * @s: the seq_file structure being used to generate output
643 * @regs: an array if struct debugfs_reg32 structures
644 * @nregs: the length of the above array
645 * @base: the base address to be used in reading the registers
646 * @prefix: a string to be prefixed to every output line
648 * This function outputs a text block describing the current values of
649 * some 32-bit hardware registers. It is meant to be used within debugfs
650 * files based on seq_file that need to show registers, intermixed with other
651 * information. The prefix argument may be used to specify a leading string,
652 * because some peripherals have several blocks of identical registers,
653 * for example configuration of dma channels
655 void debugfs_print_regs32(struct seq_file *s, const struct debugfs_reg32 *regs,
656 int nregs, void __iomem *base, char *prefix)
660 for (i = 0; i < nregs; i++, regs++) {
662 seq_printf(s, "%s", prefix);
663 seq_printf(s, "%s = 0x%08x\n", regs->name,
664 readl(base + regs->offset));
665 if (seq_has_overflowed(s))
669 EXPORT_SYMBOL_GPL(debugfs_print_regs32);
671 static int debugfs_show_regset32(struct seq_file *s, void *data)
673 struct debugfs_regset32 *regset = s->private;
675 debugfs_print_regs32(s, regset->regs, regset->nregs, regset->base, "");
679 static int debugfs_open_regset32(struct inode *inode, struct file *file)
681 return single_open(file, debugfs_show_regset32, inode->i_private);
684 static const struct file_operations fops_regset32 = {
685 .open = debugfs_open_regset32,
688 .release = single_release,
692 * debugfs_create_regset32 - create a debugfs file that returns register values
693 * @name: a pointer to a string containing the name of the file to create.
694 * @mode: the permission that the file should have
695 * @parent: a pointer to the parent dentry for this file. This should be a
696 * directory dentry if set. If this parameter is %NULL, then the
697 * file will be created in the root of the debugfs filesystem.
698 * @regset: a pointer to a struct debugfs_regset32, which contains a pointer
699 * to an array of register definitions, the array size and the base
700 * address where the register bank is to be found.
702 * This function creates a file in debugfs with the given name that reports
703 * the names and values of a set of 32-bit registers. If the @mode variable
704 * is so set it can be read from. Writing is not supported.
706 * This function will return a pointer to a dentry if it succeeds. This
707 * pointer must be passed to the debugfs_remove() function when the file is
708 * to be removed (no automatic cleanup happens if your module is unloaded,
709 * you are responsible here.) If an error occurs, %NULL will be returned.
711 * If debugfs is not enabled in the kernel, the value -%ENODEV will be
712 * returned. It is not wise to check for this value, but rather, check for
713 * %NULL or !%NULL instead as to eliminate the need for #ifdef in the calling
716 struct dentry *debugfs_create_regset32(const char *name, umode_t mode,
717 struct dentry *parent,
718 struct debugfs_regset32 *regset)
720 return debugfs_create_file(name, mode, parent, regset, &fops_regset32);
722 EXPORT_SYMBOL_GPL(debugfs_create_regset32);
724 #endif /* CONFIG_HAS_IOMEM */
726 struct debugfs_devm_entry {
727 int (*read)(struct seq_file *seq, void *data);
731 static int debugfs_devm_entry_open(struct inode *inode, struct file *f)
733 struct debugfs_devm_entry *entry = inode->i_private;
735 return single_open(f, entry->read, entry->dev);
738 static const struct file_operations debugfs_devm_entry_ops = {
739 .owner = THIS_MODULE,
740 .open = debugfs_devm_entry_open,
741 .release = single_release,
747 * debugfs_create_devm_seqfile - create a debugfs file that is bound to device.
749 * @dev: device related to this debugfs file.
750 * @name: name of the debugfs file.
751 * @parent: a pointer to the parent dentry for this file. This should be a
752 * directory dentry if set. If this parameter is %NULL, then the
753 * file will be created in the root of the debugfs filesystem.
754 * @read_fn: function pointer called to print the seq_file content.
756 struct dentry *debugfs_create_devm_seqfile(struct device *dev, const char *name,
757 struct dentry *parent,
758 int (*read_fn)(struct seq_file *s,
761 struct debugfs_devm_entry *entry;
764 return ERR_PTR(-ENOENT);
766 entry = devm_kzalloc(dev, sizeof(*entry), GFP_KERNEL);
768 return ERR_PTR(-ENOMEM);
770 entry->read = read_fn;
773 return debugfs_create_file(name, S_IRUGO, parent, entry,
774 &debugfs_devm_entry_ops);
776 EXPORT_SYMBOL_GPL(debugfs_create_devm_seqfile);