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1/*
2 * Register map access API - debugfs
3 *
4 * Copyright 2011 Wolfson Microelectronics plc
5 *
6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/slab.h>
14#include <linux/mutex.h>
15#include <linux/debugfs.h>
16#include <linux/uaccess.h>
17#include <linux/device.h>
18#include <linux/list.h>
19
20#include "internal.h"
21
22struct regmap_debugfs_node {
23 struct regmap *map;
24 const char *name;
25 struct list_head link;
26};
27
28static struct dentry *regmap_debugfs_root;
29static LIST_HEAD(regmap_debugfs_early_list);
30static DEFINE_MUTEX(regmap_debugfs_early_lock);
31
32/* Calculate the length of a fixed format */
33static size_t regmap_calc_reg_len(int max_val, char *buf, size_t buf_size)
34{
35 snprintf(buf, buf_size, "%x", max_val);
36 return strlen(buf);
37}
38
39static ssize_t regmap_name_read_file(struct file *file,
40 char __user *user_buf, size_t count,
41 loff_t *ppos)
42{
43 struct regmap *map = file->private_data;
44 int ret;
45 char *buf;
46
47 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
48 if (!buf)
49 return -ENOMEM;
50
51 ret = snprintf(buf, PAGE_SIZE, "%s\n", map->dev->driver->name);
52 if (ret < 0) {
53 kfree(buf);
54 return ret;
55 }
56
57 ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
58 kfree(buf);
59 return ret;
60}
61
62static const struct file_operations regmap_name_fops = {
63 .open = simple_open,
64 .read = regmap_name_read_file,
65 .llseek = default_llseek,
66};
67
68static void regmap_debugfs_free_dump_cache(struct regmap *map)
69{
70 struct regmap_debugfs_off_cache *c;
71
72 while (!list_empty(&map->debugfs_off_cache)) {
73 c = list_first_entry(&map->debugfs_off_cache,
74 struct regmap_debugfs_off_cache,
75 list);
76 list_del(&c->list);
77 kfree(c);
78 }
79}
80
81/*
82 * Work out where the start offset maps into register numbers, bearing
83 * in mind that we suppress hidden registers.
84 */
85static unsigned int regmap_debugfs_get_dump_start(struct regmap *map,
86 unsigned int base,
87 loff_t from,
88 loff_t *pos)
89{
90 struct regmap_debugfs_off_cache *c = NULL;
91 loff_t p = 0;
92 unsigned int i, ret;
93 unsigned int fpos_offset;
94 unsigned int reg_offset;
95
96 /* Suppress the cache if we're using a subrange */
97 if (base)
98 return base;
99
100 /*
101 * If we don't have a cache build one so we don't have to do a
102 * linear scan each time.
103 */
104 mutex_lock(&map->cache_lock);
105 i = base;
106 if (list_empty(&map->debugfs_off_cache)) {
107 for (; i <= map->max_register; i += map->reg_stride) {
108 /* Skip unprinted registers, closing off cache entry */
109 if (!regmap_readable(map, i) ||
110 regmap_precious(map, i)) {
111 if (c) {
112 c->max = p - 1;
113 c->max_reg = i - map->reg_stride;
114 list_add_tail(&c->list,
115 &map->debugfs_off_cache);
116 c = NULL;
117 }
118
119 continue;
120 }
121
122 /* No cache entry? Start a new one */
123 if (!c) {
124 c = kzalloc(sizeof(*c), GFP_KERNEL);
125 if (!c) {
126 regmap_debugfs_free_dump_cache(map);
127 mutex_unlock(&map->cache_lock);
128 return base;
129 }
130 c->min = p;
131 c->base_reg = i;
132 }
133
134 p += map->debugfs_tot_len;
135 }
136 }
137
138 /* Close the last entry off if we didn't scan beyond it */
139 if (c) {
140 c->max = p - 1;
141 c->max_reg = i - map->reg_stride;
142 list_add_tail(&c->list,
143 &map->debugfs_off_cache);
144 }
145
146 /*
147 * This should never happen; we return above if we fail to
148 * allocate and we should never be in this code if there are
149 * no registers at all.
150 */
151 WARN_ON(list_empty(&map->debugfs_off_cache));
152 ret = base;
153
154 /* Find the relevant block:offset */
155 list_for_each_entry(c, &map->debugfs_off_cache, list) {
156 if (from >= c->min && from <= c->max) {
157 fpos_offset = from - c->min;
158 reg_offset = fpos_offset / map->debugfs_tot_len;
159 *pos = c->min + (reg_offset * map->debugfs_tot_len);
160 mutex_unlock(&map->cache_lock);
161 return c->base_reg + (reg_offset * map->reg_stride);
162 }
163
164 *pos = c->max;
165 ret = c->max_reg;
166 }
167 mutex_unlock(&map->cache_lock);
168
169 return ret;
170}
171
172static inline void regmap_calc_tot_len(struct regmap *map,
173 void *buf, size_t count)
174{
175 /* Calculate the length of a fixed format */
176 if (!map->debugfs_tot_len) {
177 map->debugfs_reg_len = regmap_calc_reg_len(map->max_register,
178 buf, count);
179 map->debugfs_val_len = 2 * map->format.val_bytes;
180 map->debugfs_tot_len = map->debugfs_reg_len +
181 map->debugfs_val_len + 3; /* : \n */
182 }
183}
184
185static ssize_t regmap_read_debugfs(struct regmap *map, unsigned int from,
186 unsigned int to, char __user *user_buf,
187 size_t count, loff_t *ppos)
188{
189 size_t buf_pos = 0;
190 loff_t p = *ppos;
191 ssize_t ret;
192 int i;
193 char *buf;
194 unsigned int val, start_reg;
195
196 if (*ppos < 0 || !count)
197 return -EINVAL;
198
199 buf = kmalloc(count, GFP_KERNEL);
200 if (!buf)
201 return -ENOMEM;
202
203 regmap_calc_tot_len(map, buf, count);
204
205 /* Work out which register we're starting at */
206 start_reg = regmap_debugfs_get_dump_start(map, from, *ppos, &p);
207
208 for (i = start_reg; i <= to; i += map->reg_stride) {
209 if (!regmap_readable(map, i))
210 continue;
211
212 if (regmap_precious(map, i))
213 continue;
214
215 /* If we're in the region the user is trying to read */
216 if (p >= *ppos) {
217 /* ...but not beyond it */
218 if (buf_pos + map->debugfs_tot_len > count)
219 break;
220
221 /* Format the register */
222 snprintf(buf + buf_pos, count - buf_pos, "%.*x: ",
223 map->debugfs_reg_len, i - from);
224 buf_pos += map->debugfs_reg_len + 2;
225
226 /* Format the value, write all X if we can't read */
227 ret = regmap_read(map, i, &val);
228 if (ret == 0)
229 snprintf(buf + buf_pos, count - buf_pos,
230 "%.*x", map->debugfs_val_len, val);
231 else
232 memset(buf + buf_pos, 'X',
233 map->debugfs_val_len);
234 buf_pos += 2 * map->format.val_bytes;
235
236 buf[buf_pos++] = '\n';
237 }
238 p += map->debugfs_tot_len;
239 }
240
241 ret = buf_pos;
242
243 if (copy_to_user(user_buf, buf, buf_pos)) {
244 ret = -EFAULT;
245 goto out;
246 }
247
248 *ppos += buf_pos;
249
250out:
251 kfree(buf);
252 return ret;
253}
254
255static ssize_t regmap_map_read_file(struct file *file, char __user *user_buf,
256 size_t count, loff_t *ppos)
257{
258 struct regmap *map = file->private_data;
259
260 return regmap_read_debugfs(map, 0, map->max_register, user_buf,
261 count, ppos);
262}
263
264#undef REGMAP_ALLOW_WRITE_DEBUGFS
265#ifdef REGMAP_ALLOW_WRITE_DEBUGFS
266/*
267 * This can be dangerous especially when we have clients such as
268 * PMICs, therefore don't provide any real compile time configuration option
269 * for this feature, people who want to use this will need to modify
270 * the source code directly.
271 */
272static ssize_t regmap_map_write_file(struct file *file,
273 const char __user *user_buf,
274 size_t count, loff_t *ppos)
275{
276 char buf[32];
277 size_t buf_size;
278 char *start = buf;
279 unsigned long reg, value;
280 struct regmap *map = file->private_data;
281 int ret;
282
283 buf_size = min(count, (sizeof(buf)-1));
284 if (copy_from_user(buf, user_buf, buf_size))
285 return -EFAULT;
286 buf[buf_size] = 0;
287
288 while (*start == ' ')
289 start++;
290 reg = simple_strtoul(start, &start, 16);
291 while (*start == ' ')
292 start++;
293 if (kstrtoul(start, 16, &value))
294 return -EINVAL;
295
296 /* Userspace has been fiddling around behind the kernel's back */
297 add_taint(TAINT_USER, LOCKDEP_STILL_OK);
298
299 ret = regmap_write(map, reg, value);
300 if (ret < 0)
301 return ret;
302 return buf_size;
303}
304#else
305#define regmap_map_write_file NULL
306#endif
307
308static const struct file_operations regmap_map_fops = {
309 .open = simple_open,
310 .read = regmap_map_read_file,
311 .write = regmap_map_write_file,
312 .llseek = default_llseek,
313};
314
315static ssize_t regmap_range_read_file(struct file *file, char __user *user_buf,
316 size_t count, loff_t *ppos)
317{
318 struct regmap_range_node *range = file->private_data;
319 struct regmap *map = range->map;
320
321 return regmap_read_debugfs(map, range->range_min, range->range_max,
322 user_buf, count, ppos);
323}
324
325static const struct file_operations regmap_range_fops = {
326 .open = simple_open,
327 .read = regmap_range_read_file,
328 .llseek = default_llseek,
329};
330
331static ssize_t regmap_reg_ranges_read_file(struct file *file,
332 char __user *user_buf, size_t count,
333 loff_t *ppos)
334{
335 struct regmap *map = file->private_data;
336 struct regmap_debugfs_off_cache *c;
337 loff_t p = 0;
338 size_t buf_pos = 0;
339 char *buf;
340 char *entry;
341 int ret;
342
343 if (*ppos < 0 || !count)
344 return -EINVAL;
345
346 buf = kmalloc(count, GFP_KERNEL);
347 if (!buf)
348 return -ENOMEM;
349
350 entry = kmalloc(PAGE_SIZE, GFP_KERNEL);
351 if (!entry) {
352 kfree(buf);
353 return -ENOMEM;
354 }
355
356 /* While we are at it, build the register dump cache
357 * now so the read() operation on the `registers' file
358 * can benefit from using the cache. We do not care
359 * about the file position information that is contained
360 * in the cache, just about the actual register blocks */
361 regmap_calc_tot_len(map, buf, count);
362 regmap_debugfs_get_dump_start(map, 0, *ppos, &p);
363
364 /* Reset file pointer as the fixed-format of the `registers'
365 * file is not compatible with the `range' file */
366 p = 0;
367 mutex_lock(&map->cache_lock);
368 list_for_each_entry(c, &map->debugfs_off_cache, list) {
369 snprintf(entry, PAGE_SIZE, "%x-%x",
370 c->base_reg, c->max_reg);
371 if (p >= *ppos) {
372 if (buf_pos + 1 + strlen(entry) > count)
373 break;
374 snprintf(buf + buf_pos, count - buf_pos,
375 "%s", entry);
376 buf_pos += strlen(entry);
377 buf[buf_pos] = '\n';
378 buf_pos++;
379 }
380 p += strlen(entry) + 1;
381 }
382 mutex_unlock(&map->cache_lock);
383
384 kfree(entry);
385 ret = buf_pos;
386
387 if (copy_to_user(user_buf, buf, buf_pos)) {
388 ret = -EFAULT;
389 goto out_buf;
390 }
391
392 *ppos += buf_pos;
393out_buf:
394 kfree(buf);
395 return ret;
396}
397
398static const struct file_operations regmap_reg_ranges_fops = {
399 .open = simple_open,
400 .read = regmap_reg_ranges_read_file,
401 .llseek = default_llseek,
402};
403
404static ssize_t regmap_access_read_file(struct file *file,
405 char __user *user_buf, size_t count,
406 loff_t *ppos)
407{
408 int reg_len, tot_len;
409 size_t buf_pos = 0;
410 loff_t p = 0;
411 ssize_t ret;
412 int i;
413 struct regmap *map = file->private_data;
414 char *buf;
415
416 if (*ppos < 0 || !count)
417 return -EINVAL;
418
419 buf = kmalloc(count, GFP_KERNEL);
420 if (!buf)
421 return -ENOMEM;
422
423 /* Calculate the length of a fixed format */
424 reg_len = regmap_calc_reg_len(map->max_register, buf, count);
425 tot_len = reg_len + 10; /* ': R W V P\n' */
426
427 for (i = 0; i <= map->max_register; i += map->reg_stride) {
428 /* Ignore registers which are neither readable nor writable */
429 if (!regmap_readable(map, i) && !regmap_writeable(map, i))
430 continue;
431
432 /* If we're in the region the user is trying to read */
433 if (p >= *ppos) {
434 /* ...but not beyond it */
435 if (buf_pos >= count - 1 - tot_len)
436 break;
437
438 /* Format the register */
439 snprintf(buf + buf_pos, count - buf_pos,
440 "%.*x: %c %c %c %c\n",
441 reg_len, i,
442 regmap_readable(map, i) ? 'y' : 'n',
443 regmap_writeable(map, i) ? 'y' : 'n',
444 regmap_volatile(map, i) ? 'y' : 'n',
445 regmap_precious(map, i) ? 'y' : 'n');
446
447 buf_pos += tot_len;
448 }
449 p += tot_len;
450 }
451
452 ret = buf_pos;
453
454 if (copy_to_user(user_buf, buf, buf_pos)) {
455 ret = -EFAULT;
456 goto out;
457 }
458
459 *ppos += buf_pos;
460
461out:
462 kfree(buf);
463 return ret;
464}
465
466static const struct file_operations regmap_access_fops = {
467 .open = simple_open,
468 .read = regmap_access_read_file,
469 .llseek = default_llseek,
470};
471
472void regmap_debugfs_init(struct regmap *map, const char *name)
473{
474 struct rb_node *next;
475 struct regmap_range_node *range_node;
476
477 /* If we don't have the debugfs root yet, postpone init */
478 if (!regmap_debugfs_root) {
479 struct regmap_debugfs_node *node;
480 node = kzalloc(sizeof(*node), GFP_KERNEL);
481 if (!node)
482 return;
483 node->map = map;
484 node->name = name;
485 mutex_lock(®map_debugfs_early_lock);
486 list_add(&node->link, ®map_debugfs_early_list);
487 mutex_unlock(®map_debugfs_early_lock);
488 return;
489 }
490
491 INIT_LIST_HEAD(&map->debugfs_off_cache);
492 mutex_init(&map->cache_lock);
493
494 if (name) {
495 map->debugfs_name = kasprintf(GFP_KERNEL, "%s-%s",
496 dev_name(map->dev), name);
497 name = map->debugfs_name;
498 } else {
499 name = dev_name(map->dev);
500 }
501
502 map->debugfs = debugfs_create_dir(name, regmap_debugfs_root);
503 if (!map->debugfs) {
504 dev_warn(map->dev, "Failed to create debugfs directory\n");
505 return;
506 }
507
508 debugfs_create_file("name", 0400, map->debugfs,
509 map, ®map_name_fops);
510
511 debugfs_create_file("range", 0400, map->debugfs,
512 map, ®map_reg_ranges_fops);
513
514 if (map->max_register || regmap_readable(map, 0)) {
515 debugfs_create_file("registers", 0400, map->debugfs,
516 map, ®map_map_fops);
517 debugfs_create_file("access", 0400, map->debugfs,
518 map, ®map_access_fops);
519 }
520
521 if (map->cache_type) {
522 debugfs_create_bool("cache_only", 0400, map->debugfs,
523 &map->cache_only);
524 debugfs_create_bool("cache_dirty", 0400, map->debugfs,
525 &map->cache_dirty);
526 debugfs_create_bool("cache_bypass", 0400, map->debugfs,
527 &map->cache_bypass);
528 }
529
530 next = rb_first(&map->range_tree);
531 while (next) {
532 range_node = rb_entry(next, struct regmap_range_node, node);
533
534 if (range_node->name)
535 debugfs_create_file(range_node->name, 0400,
536 map->debugfs, range_node,
537 ®map_range_fops);
538
539 next = rb_next(&range_node->node);
540 }
541}
542
543void regmap_debugfs_exit(struct regmap *map)
544{
545 if (map->debugfs) {
546 debugfs_remove_recursive(map->debugfs);
547 mutex_lock(&map->cache_lock);
548 regmap_debugfs_free_dump_cache(map);
549 mutex_unlock(&map->cache_lock);
550 kfree(map->debugfs_name);
551 } else {
552 struct regmap_debugfs_node *node, *tmp;
553
554 mutex_lock(®map_debugfs_early_lock);
555 list_for_each_entry_safe(node, tmp, ®map_debugfs_early_list,
556 link) {
557 if (node->map == map) {
558 list_del(&node->link);
559 kfree(node);
560 }
561 }
562 mutex_unlock(®map_debugfs_early_lock);
563 }
564}
565
566void regmap_debugfs_initcall(void)
567{
568 struct regmap_debugfs_node *node, *tmp;
569
570 regmap_debugfs_root = debugfs_create_dir("regmap", NULL);
571 if (!regmap_debugfs_root) {
572 pr_warn("regmap: Failed to create debugfs root\n");
573 return;
574 }
575
576 mutex_lock(®map_debugfs_early_lock);
577 list_for_each_entry_safe(node, tmp, ®map_debugfs_early_list, link) {
578 regmap_debugfs_init(node->map, node->name);
579 list_del(&node->link);
580 kfree(node);
581 }
582 mutex_unlock(®map_debugfs_early_lock);
583}
1/*
2 * Register map access API - debugfs
3 *
4 * Copyright 2011 Wolfson Microelectronics plc
5 *
6 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13#include <linux/slab.h>
14#include <linux/mutex.h>
15#include <linux/debugfs.h>
16#include <linux/uaccess.h>
17#include <linux/device.h>
18#include <linux/list.h>
19
20#include "internal.h"
21
22struct regmap_debugfs_node {
23 struct regmap *map;
24 const char *name;
25 struct list_head link;
26};
27
28static struct dentry *regmap_debugfs_root;
29static LIST_HEAD(regmap_debugfs_early_list);
30static DEFINE_MUTEX(regmap_debugfs_early_lock);
31
32/* Calculate the length of a fixed format */
33static size_t regmap_calc_reg_len(int max_val)
34{
35 return snprintf(NULL, 0, "%x", max_val);
36}
37
38static ssize_t regmap_name_read_file(struct file *file,
39 char __user *user_buf, size_t count,
40 loff_t *ppos)
41{
42 struct regmap *map = file->private_data;
43 int ret;
44 char *buf;
45
46 buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
47 if (!buf)
48 return -ENOMEM;
49
50 ret = snprintf(buf, PAGE_SIZE, "%s\n", map->dev->driver->name);
51 if (ret < 0) {
52 kfree(buf);
53 return ret;
54 }
55
56 ret = simple_read_from_buffer(user_buf, count, ppos, buf, ret);
57 kfree(buf);
58 return ret;
59}
60
61static const struct file_operations regmap_name_fops = {
62 .open = simple_open,
63 .read = regmap_name_read_file,
64 .llseek = default_llseek,
65};
66
67static void regmap_debugfs_free_dump_cache(struct regmap *map)
68{
69 struct regmap_debugfs_off_cache *c;
70
71 while (!list_empty(&map->debugfs_off_cache)) {
72 c = list_first_entry(&map->debugfs_off_cache,
73 struct regmap_debugfs_off_cache,
74 list);
75 list_del(&c->list);
76 kfree(c);
77 }
78}
79
80/*
81 * Work out where the start offset maps into register numbers, bearing
82 * in mind that we suppress hidden registers.
83 */
84static unsigned int regmap_debugfs_get_dump_start(struct regmap *map,
85 unsigned int base,
86 loff_t from,
87 loff_t *pos)
88{
89 struct regmap_debugfs_off_cache *c = NULL;
90 loff_t p = 0;
91 unsigned int i, ret;
92 unsigned int fpos_offset;
93 unsigned int reg_offset;
94
95 /* Suppress the cache if we're using a subrange */
96 if (base)
97 return base;
98
99 /*
100 * If we don't have a cache build one so we don't have to do a
101 * linear scan each time.
102 */
103 mutex_lock(&map->cache_lock);
104 i = base;
105 if (list_empty(&map->debugfs_off_cache)) {
106 for (; i <= map->max_register; i += map->reg_stride) {
107 /* Skip unprinted registers, closing off cache entry */
108 if (!regmap_readable(map, i) ||
109 regmap_precious(map, i)) {
110 if (c) {
111 c->max = p - 1;
112 c->max_reg = i - map->reg_stride;
113 list_add_tail(&c->list,
114 &map->debugfs_off_cache);
115 c = NULL;
116 }
117
118 continue;
119 }
120
121 /* No cache entry? Start a new one */
122 if (!c) {
123 c = kzalloc(sizeof(*c), GFP_KERNEL);
124 if (!c) {
125 regmap_debugfs_free_dump_cache(map);
126 mutex_unlock(&map->cache_lock);
127 return base;
128 }
129 c->min = p;
130 c->base_reg = i;
131 }
132
133 p += map->debugfs_tot_len;
134 }
135 }
136
137 /* Close the last entry off if we didn't scan beyond it */
138 if (c) {
139 c->max = p - 1;
140 c->max_reg = i - map->reg_stride;
141 list_add_tail(&c->list,
142 &map->debugfs_off_cache);
143 }
144
145 /*
146 * This should never happen; we return above if we fail to
147 * allocate and we should never be in this code if there are
148 * no registers at all.
149 */
150 WARN_ON(list_empty(&map->debugfs_off_cache));
151 ret = base;
152
153 /* Find the relevant block:offset */
154 list_for_each_entry(c, &map->debugfs_off_cache, list) {
155 if (from >= c->min && from <= c->max) {
156 fpos_offset = from - c->min;
157 reg_offset = fpos_offset / map->debugfs_tot_len;
158 *pos = c->min + (reg_offset * map->debugfs_tot_len);
159 mutex_unlock(&map->cache_lock);
160 return c->base_reg + (reg_offset * map->reg_stride);
161 }
162
163 *pos = c->max;
164 ret = c->max_reg;
165 }
166 mutex_unlock(&map->cache_lock);
167
168 return ret;
169}
170
171static inline void regmap_calc_tot_len(struct regmap *map,
172 void *buf, size_t count)
173{
174 /* Calculate the length of a fixed format */
175 if (!map->debugfs_tot_len) {
176 map->debugfs_reg_len = regmap_calc_reg_len(map->max_register),
177 map->debugfs_val_len = 2 * map->format.val_bytes;
178 map->debugfs_tot_len = map->debugfs_reg_len +
179 map->debugfs_val_len + 3; /* : \n */
180 }
181}
182
183static ssize_t regmap_read_debugfs(struct regmap *map, unsigned int from,
184 unsigned int to, char __user *user_buf,
185 size_t count, loff_t *ppos)
186{
187 size_t buf_pos = 0;
188 loff_t p = *ppos;
189 ssize_t ret;
190 int i;
191 char *buf;
192 unsigned int val, start_reg;
193
194 if (*ppos < 0 || !count)
195 return -EINVAL;
196
197 buf = kmalloc(count, GFP_KERNEL);
198 if (!buf)
199 return -ENOMEM;
200
201 regmap_calc_tot_len(map, buf, count);
202
203 /* Work out which register we're starting at */
204 start_reg = regmap_debugfs_get_dump_start(map, from, *ppos, &p);
205
206 for (i = start_reg; i <= to; i += map->reg_stride) {
207 if (!regmap_readable(map, i))
208 continue;
209
210 if (regmap_precious(map, i))
211 continue;
212
213 /* If we're in the region the user is trying to read */
214 if (p >= *ppos) {
215 /* ...but not beyond it */
216 if (buf_pos + map->debugfs_tot_len > count)
217 break;
218
219 /* Format the register */
220 snprintf(buf + buf_pos, count - buf_pos, "%.*x: ",
221 map->debugfs_reg_len, i - from);
222 buf_pos += map->debugfs_reg_len + 2;
223
224 /* Format the value, write all X if we can't read */
225 ret = regmap_read(map, i, &val);
226 if (ret == 0)
227 snprintf(buf + buf_pos, count - buf_pos,
228 "%.*x", map->debugfs_val_len, val);
229 else
230 memset(buf + buf_pos, 'X',
231 map->debugfs_val_len);
232 buf_pos += 2 * map->format.val_bytes;
233
234 buf[buf_pos++] = '\n';
235 }
236 p += map->debugfs_tot_len;
237 }
238
239 ret = buf_pos;
240
241 if (copy_to_user(user_buf, buf, buf_pos)) {
242 ret = -EFAULT;
243 goto out;
244 }
245
246 *ppos += buf_pos;
247
248out:
249 kfree(buf);
250 return ret;
251}
252
253static ssize_t regmap_map_read_file(struct file *file, char __user *user_buf,
254 size_t count, loff_t *ppos)
255{
256 struct regmap *map = file->private_data;
257
258 return regmap_read_debugfs(map, 0, map->max_register, user_buf,
259 count, ppos);
260}
261
262#undef REGMAP_ALLOW_WRITE_DEBUGFS
263#ifdef REGMAP_ALLOW_WRITE_DEBUGFS
264/*
265 * This can be dangerous especially when we have clients such as
266 * PMICs, therefore don't provide any real compile time configuration option
267 * for this feature, people who want to use this will need to modify
268 * the source code directly.
269 */
270static ssize_t regmap_map_write_file(struct file *file,
271 const char __user *user_buf,
272 size_t count, loff_t *ppos)
273{
274 char buf[32];
275 size_t buf_size;
276 char *start = buf;
277 unsigned long reg, value;
278 struct regmap *map = file->private_data;
279 int ret;
280
281 buf_size = min(count, (sizeof(buf)-1));
282 if (copy_from_user(buf, user_buf, buf_size))
283 return -EFAULT;
284 buf[buf_size] = 0;
285
286 while (*start == ' ')
287 start++;
288 reg = simple_strtoul(start, &start, 16);
289 while (*start == ' ')
290 start++;
291 if (kstrtoul(start, 16, &value))
292 return -EINVAL;
293
294 /* Userspace has been fiddling around behind the kernel's back */
295 add_taint(TAINT_USER, LOCKDEP_STILL_OK);
296
297 ret = regmap_write(map, reg, value);
298 if (ret < 0)
299 return ret;
300 return buf_size;
301}
302#else
303#define regmap_map_write_file NULL
304#endif
305
306static const struct file_operations regmap_map_fops = {
307 .open = simple_open,
308 .read = regmap_map_read_file,
309 .write = regmap_map_write_file,
310 .llseek = default_llseek,
311};
312
313static ssize_t regmap_range_read_file(struct file *file, char __user *user_buf,
314 size_t count, loff_t *ppos)
315{
316 struct regmap_range_node *range = file->private_data;
317 struct regmap *map = range->map;
318
319 return regmap_read_debugfs(map, range->range_min, range->range_max,
320 user_buf, count, ppos);
321}
322
323static const struct file_operations regmap_range_fops = {
324 .open = simple_open,
325 .read = regmap_range_read_file,
326 .llseek = default_llseek,
327};
328
329static ssize_t regmap_reg_ranges_read_file(struct file *file,
330 char __user *user_buf, size_t count,
331 loff_t *ppos)
332{
333 struct regmap *map = file->private_data;
334 struct regmap_debugfs_off_cache *c;
335 loff_t p = 0;
336 size_t buf_pos = 0;
337 char *buf;
338 char *entry;
339 int ret;
340 unsigned entry_len;
341
342 if (*ppos < 0 || !count)
343 return -EINVAL;
344
345 buf = kmalloc(count, GFP_KERNEL);
346 if (!buf)
347 return -ENOMEM;
348
349 entry = kmalloc(PAGE_SIZE, GFP_KERNEL);
350 if (!entry) {
351 kfree(buf);
352 return -ENOMEM;
353 }
354
355 /* While we are at it, build the register dump cache
356 * now so the read() operation on the `registers' file
357 * can benefit from using the cache. We do not care
358 * about the file position information that is contained
359 * in the cache, just about the actual register blocks */
360 regmap_calc_tot_len(map, buf, count);
361 regmap_debugfs_get_dump_start(map, 0, *ppos, &p);
362
363 /* Reset file pointer as the fixed-format of the `registers'
364 * file is not compatible with the `range' file */
365 p = 0;
366 mutex_lock(&map->cache_lock);
367 list_for_each_entry(c, &map->debugfs_off_cache, list) {
368 entry_len = snprintf(entry, PAGE_SIZE, "%x-%x\n",
369 c->base_reg, c->max_reg);
370 if (p >= *ppos) {
371 if (buf_pos + entry_len > count)
372 break;
373 memcpy(buf + buf_pos, entry, entry_len);
374 buf_pos += entry_len;
375 }
376 p += entry_len;
377 }
378 mutex_unlock(&map->cache_lock);
379
380 kfree(entry);
381 ret = buf_pos;
382
383 if (copy_to_user(user_buf, buf, buf_pos)) {
384 ret = -EFAULT;
385 goto out_buf;
386 }
387
388 *ppos += buf_pos;
389out_buf:
390 kfree(buf);
391 return ret;
392}
393
394static const struct file_operations regmap_reg_ranges_fops = {
395 .open = simple_open,
396 .read = regmap_reg_ranges_read_file,
397 .llseek = default_llseek,
398};
399
400static int regmap_access_show(struct seq_file *s, void *ignored)
401{
402 struct regmap *map = s->private;
403 int i, reg_len;
404
405 reg_len = regmap_calc_reg_len(map->max_register);
406
407 for (i = 0; i <= map->max_register; i += map->reg_stride) {
408 /* Ignore registers which are neither readable nor writable */
409 if (!regmap_readable(map, i) && !regmap_writeable(map, i))
410 continue;
411
412 /* Format the register */
413 seq_printf(s, "%.*x: %c %c %c %c\n", reg_len, i,
414 regmap_readable(map, i) ? 'y' : 'n',
415 regmap_writeable(map, i) ? 'y' : 'n',
416 regmap_volatile(map, i) ? 'y' : 'n',
417 regmap_precious(map, i) ? 'y' : 'n');
418 }
419
420 return 0;
421}
422
423static int access_open(struct inode *inode, struct file *file)
424{
425 return single_open(file, regmap_access_show, inode->i_private);
426}
427
428static const struct file_operations regmap_access_fops = {
429 .open = access_open,
430 .read = seq_read,
431 .llseek = seq_lseek,
432 .release = single_release,
433};
434
435static ssize_t regmap_cache_only_write_file(struct file *file,
436 const char __user *user_buf,
437 size_t count, loff_t *ppos)
438{
439 struct regmap *map = container_of(file->private_data,
440 struct regmap, cache_only);
441 ssize_t result;
442 bool was_enabled, require_sync = false;
443 int err;
444
445 map->lock(map->lock_arg);
446
447 was_enabled = map->cache_only;
448
449 result = debugfs_write_file_bool(file, user_buf, count, ppos);
450 if (result < 0) {
451 map->unlock(map->lock_arg);
452 return result;
453 }
454
455 if (map->cache_only && !was_enabled) {
456 dev_warn(map->dev, "debugfs cache_only=Y forced\n");
457 add_taint(TAINT_USER, LOCKDEP_STILL_OK);
458 } else if (!map->cache_only && was_enabled) {
459 dev_warn(map->dev, "debugfs cache_only=N forced: syncing cache\n");
460 require_sync = true;
461 }
462
463 map->unlock(map->lock_arg);
464
465 if (require_sync) {
466 err = regcache_sync(map);
467 if (err)
468 dev_err(map->dev, "Failed to sync cache %d\n", err);
469 }
470
471 return result;
472}
473
474static const struct file_operations regmap_cache_only_fops = {
475 .open = simple_open,
476 .read = debugfs_read_file_bool,
477 .write = regmap_cache_only_write_file,
478};
479
480static ssize_t regmap_cache_bypass_write_file(struct file *file,
481 const char __user *user_buf,
482 size_t count, loff_t *ppos)
483{
484 struct regmap *map = container_of(file->private_data,
485 struct regmap, cache_bypass);
486 ssize_t result;
487 bool was_enabled;
488
489 map->lock(map->lock_arg);
490
491 was_enabled = map->cache_bypass;
492
493 result = debugfs_write_file_bool(file, user_buf, count, ppos);
494 if (result < 0)
495 goto out;
496
497 if (map->cache_bypass && !was_enabled) {
498 dev_warn(map->dev, "debugfs cache_bypass=Y forced\n");
499 add_taint(TAINT_USER, LOCKDEP_STILL_OK);
500 } else if (!map->cache_bypass && was_enabled) {
501 dev_warn(map->dev, "debugfs cache_bypass=N forced\n");
502 }
503
504out:
505 map->unlock(map->lock_arg);
506
507 return result;
508}
509
510static const struct file_operations regmap_cache_bypass_fops = {
511 .open = simple_open,
512 .read = debugfs_read_file_bool,
513 .write = regmap_cache_bypass_write_file,
514};
515
516void regmap_debugfs_init(struct regmap *map, const char *name)
517{
518 struct rb_node *next;
519 struct regmap_range_node *range_node;
520 const char *devname = "dummy";
521
522 /* If we don't have the debugfs root yet, postpone init */
523 if (!regmap_debugfs_root) {
524 struct regmap_debugfs_node *node;
525 node = kzalloc(sizeof(*node), GFP_KERNEL);
526 if (!node)
527 return;
528 node->map = map;
529 node->name = name;
530 mutex_lock(®map_debugfs_early_lock);
531 list_add(&node->link, ®map_debugfs_early_list);
532 mutex_unlock(®map_debugfs_early_lock);
533 return;
534 }
535
536 INIT_LIST_HEAD(&map->debugfs_off_cache);
537 mutex_init(&map->cache_lock);
538
539 if (map->dev)
540 devname = dev_name(map->dev);
541
542 if (name) {
543 map->debugfs_name = kasprintf(GFP_KERNEL, "%s-%s",
544 devname, name);
545 name = map->debugfs_name;
546 } else {
547 name = devname;
548 }
549
550 map->debugfs = debugfs_create_dir(name, regmap_debugfs_root);
551 if (!map->debugfs) {
552 dev_warn(map->dev, "Failed to create debugfs directory\n");
553 return;
554 }
555
556 debugfs_create_file("name", 0400, map->debugfs,
557 map, ®map_name_fops);
558
559 debugfs_create_file("range", 0400, map->debugfs,
560 map, ®map_reg_ranges_fops);
561
562 if (map->max_register || regmap_readable(map, 0)) {
563 umode_t registers_mode;
564
565#if defined(REGMAP_ALLOW_WRITE_DEBUGFS)
566 registers_mode = 0600;
567#else
568 registers_mode = 0400;
569#endif
570
571 debugfs_create_file("registers", registers_mode, map->debugfs,
572 map, ®map_map_fops);
573 debugfs_create_file("access", 0400, map->debugfs,
574 map, ®map_access_fops);
575 }
576
577 if (map->cache_type) {
578 debugfs_create_file("cache_only", 0600, map->debugfs,
579 &map->cache_only, ®map_cache_only_fops);
580 debugfs_create_bool("cache_dirty", 0400, map->debugfs,
581 &map->cache_dirty);
582 debugfs_create_file("cache_bypass", 0600, map->debugfs,
583 &map->cache_bypass,
584 ®map_cache_bypass_fops);
585 }
586
587 next = rb_first(&map->range_tree);
588 while (next) {
589 range_node = rb_entry(next, struct regmap_range_node, node);
590
591 if (range_node->name)
592 debugfs_create_file(range_node->name, 0400,
593 map->debugfs, range_node,
594 ®map_range_fops);
595
596 next = rb_next(&range_node->node);
597 }
598
599 if (map->cache_ops && map->cache_ops->debugfs_init)
600 map->cache_ops->debugfs_init(map);
601}
602
603void regmap_debugfs_exit(struct regmap *map)
604{
605 if (map->debugfs) {
606 debugfs_remove_recursive(map->debugfs);
607 mutex_lock(&map->cache_lock);
608 regmap_debugfs_free_dump_cache(map);
609 mutex_unlock(&map->cache_lock);
610 kfree(map->debugfs_name);
611 } else {
612 struct regmap_debugfs_node *node, *tmp;
613
614 mutex_lock(®map_debugfs_early_lock);
615 list_for_each_entry_safe(node, tmp, ®map_debugfs_early_list,
616 link) {
617 if (node->map == map) {
618 list_del(&node->link);
619 kfree(node);
620 }
621 }
622 mutex_unlock(®map_debugfs_early_lock);
623 }
624}
625
626void regmap_debugfs_initcall(void)
627{
628 struct regmap_debugfs_node *node, *tmp;
629
630 regmap_debugfs_root = debugfs_create_dir("regmap", NULL);
631 if (!regmap_debugfs_root) {
632 pr_warn("regmap: Failed to create debugfs root\n");
633 return;
634 }
635
636 mutex_lock(®map_debugfs_early_lock);
637 list_for_each_entry_safe(node, tmp, ®map_debugfs_early_list, link) {
638 regmap_debugfs_init(node->map, node->name);
639 list_del(&node->link);
640 kfree(node);
641 }
642 mutex_unlock(®map_debugfs_early_lock);
643}