7888af7941a0fefd34460e10c8d544106b6cbb6f
[platform/adaptation/renesas_rcar/renesas_kernel.git] / drivers / base / firmware_class.c
1 /*
2  * firmware_class.c - Multi purpose firmware loading support
3  *
4  * Copyright (c) 2003 Manuel Estrada Sainz
5  *
6  * Please see Documentation/firmware_class/ for more information.
7  *
8  */
9
10 #include <linux/capability.h>
11 #include <linux/device.h>
12 #include <linux/module.h>
13 #include <linux/init.h>
14 #include <linux/timer.h>
15 #include <linux/vmalloc.h>
16 #include <linux/interrupt.h>
17 #include <linux/bitops.h>
18 #include <linux/mutex.h>
19 #include <linux/workqueue.h>
20 #include <linux/highmem.h>
21 #include <linux/firmware.h>
22 #include <linux/slab.h>
23 #include <linux/sched.h>
24 #include <linux/file.h>
25 #include <linux/list.h>
26 #include <linux/async.h>
27 #include <linux/pm.h>
28 #include <linux/suspend.h>
29 #include <linux/syscore_ops.h>
30
31 #include <generated/utsrelease.h>
32
33 #include "base.h"
34
35 MODULE_AUTHOR("Manuel Estrada Sainz");
36 MODULE_DESCRIPTION("Multi purpose firmware loading support");
37 MODULE_LICENSE("GPL");
38
39 /* Builtin firmware support */
40
41 #ifdef CONFIG_FW_LOADER
42
43 extern struct builtin_fw __start_builtin_fw[];
44 extern struct builtin_fw __end_builtin_fw[];
45
46 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
47 {
48         struct builtin_fw *b_fw;
49
50         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
51                 if (strcmp(name, b_fw->name) == 0) {
52                         fw->size = b_fw->size;
53                         fw->data = b_fw->data;
54                         return true;
55                 }
56         }
57
58         return false;
59 }
60
61 static bool fw_is_builtin_firmware(const struct firmware *fw)
62 {
63         struct builtin_fw *b_fw;
64
65         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
66                 if (fw->data == b_fw->data)
67                         return true;
68
69         return false;
70 }
71
72 #else /* Module case - no builtin firmware support */
73
74 static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
75 {
76         return false;
77 }
78
79 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
80 {
81         return false;
82 }
83 #endif
84
85 enum {
86         FW_STATUS_LOADING,
87         FW_STATUS_DONE,
88         FW_STATUS_ABORT,
89 };
90
91 enum fw_buf_fmt {
92         VMALLOC_BUF,    /* used in direct loading */
93         PAGE_BUF,       /* used in loading via userspace */
94 };
95
96 static int loading_timeout = 60;        /* In seconds */
97
98 static inline long firmware_loading_timeout(void)
99 {
100         return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
101 }
102
103 struct firmware_cache {
104         /* firmware_buf instance will be added into the below list */
105         spinlock_t lock;
106         struct list_head head;
107         int state;
108
109 #ifdef CONFIG_PM_SLEEP
110         /*
111          * Names of firmware images which have been cached successfully
112          * will be added into the below list so that device uncache
113          * helper can trace which firmware images have been cached
114          * before.
115          */
116         spinlock_t name_lock;
117         struct list_head fw_names;
118
119         struct delayed_work work;
120
121         struct notifier_block   pm_notify;
122 #endif
123 };
124
125 struct firmware_buf {
126         struct kref ref;
127         struct list_head list;
128         struct completion completion;
129         struct firmware_cache *fwc;
130         unsigned long status;
131         enum fw_buf_fmt fmt;
132         void *data;
133         size_t size;
134         struct page **pages;
135         int nr_pages;
136         int page_array_size;
137         char fw_id[];
138 };
139
140 struct fw_cache_entry {
141         struct list_head list;
142         char name[];
143 };
144
145 struct firmware_priv {
146         struct delayed_work timeout_work;
147         bool nowait;
148         struct device dev;
149         struct firmware_buf *buf;
150         struct firmware *fw;
151 };
152
153 struct fw_name_devm {
154         unsigned long magic;
155         char name[];
156 };
157
158 #define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
159
160 #define FW_LOADER_NO_CACHE      0
161 #define FW_LOADER_START_CACHE   1
162
163 static int fw_cache_piggyback_on_request(const char *name);
164
165 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
166  * guarding for corner cases a global lock should be OK */
167 static DEFINE_MUTEX(fw_lock);
168
169 static struct firmware_cache fw_cache;
170
171 static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
172                                               struct firmware_cache *fwc)
173 {
174         struct firmware_buf *buf;
175
176         buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1 , GFP_ATOMIC);
177
178         if (!buf)
179                 return buf;
180
181         kref_init(&buf->ref);
182         strcpy(buf->fw_id, fw_name);
183         buf->fwc = fwc;
184         init_completion(&buf->completion);
185         buf->fmt = VMALLOC_BUF;
186
187         pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
188
189         return buf;
190 }
191
192 static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
193 {
194         struct firmware_buf *tmp;
195         struct firmware_cache *fwc = &fw_cache;
196
197         list_for_each_entry(tmp, &fwc->head, list)
198                 if (!strcmp(tmp->fw_id, fw_name))
199                         return tmp;
200         return NULL;
201 }
202
203 static int fw_lookup_and_allocate_buf(const char *fw_name,
204                                       struct firmware_cache *fwc,
205                                       struct firmware_buf **buf)
206 {
207         struct firmware_buf *tmp;
208
209         spin_lock(&fwc->lock);
210         tmp = __fw_lookup_buf(fw_name);
211         if (tmp) {
212                 kref_get(&tmp->ref);
213                 spin_unlock(&fwc->lock);
214                 *buf = tmp;
215                 return 1;
216         }
217         tmp = __allocate_fw_buf(fw_name, fwc);
218         if (tmp)
219                 list_add(&tmp->list, &fwc->head);
220         spin_unlock(&fwc->lock);
221
222         *buf = tmp;
223
224         return tmp ? 0 : -ENOMEM;
225 }
226
227 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
228 {
229         struct firmware_buf *tmp;
230         struct firmware_cache *fwc = &fw_cache;
231
232         spin_lock(&fwc->lock);
233         tmp = __fw_lookup_buf(fw_name);
234         spin_unlock(&fwc->lock);
235
236         return tmp;
237 }
238
239 static void __fw_free_buf(struct kref *ref)
240 {
241         struct firmware_buf *buf = to_fwbuf(ref);
242         struct firmware_cache *fwc = buf->fwc;
243         int i;
244
245         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
246                  __func__, buf->fw_id, buf, buf->data,
247                  (unsigned int)buf->size);
248
249         list_del(&buf->list);
250         spin_unlock(&fwc->lock);
251
252
253         if (buf->fmt == PAGE_BUF) {
254                 vunmap(buf->data);
255                 for (i = 0; i < buf->nr_pages; i++)
256                         __free_page(buf->pages[i]);
257                 kfree(buf->pages);
258         } else
259                 vfree(buf->data);
260         kfree(buf);
261 }
262
263 static void fw_free_buf(struct firmware_buf *buf)
264 {
265         struct firmware_cache *fwc = buf->fwc;
266         spin_lock(&fwc->lock);
267         if (!kref_put(&buf->ref, __fw_free_buf))
268                 spin_unlock(&fwc->lock);
269 }
270
271 /* direct firmware loading support */
272 static char fw_path_para[256];
273 static const char * const fw_path[] = {
274         fw_path_para,
275         "/lib/firmware/updates/" UTS_RELEASE,
276         "/lib/firmware/updates",
277         "/lib/firmware/" UTS_RELEASE,
278         "/lib/firmware"
279 };
280
281 /*
282  * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
283  * from kernel command line because firmware_class is generally built in
284  * kernel instead of module.
285  */
286 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
287 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
288
289 /* Don't inline this: 'struct kstat' is biggish */
290 static noinline_for_stack long fw_file_size(struct file *file)
291 {
292         struct kstat st;
293         if (vfs_getattr(file->f_path.mnt, file->f_path.dentry, &st))
294                 return -1;
295         if (!S_ISREG(st.mode))
296                 return -1;
297         if (st.size != (long)st.size)
298                 return -1;
299         return st.size;
300 }
301
302 static bool fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
303 {
304         long size;
305         char *buf;
306
307         size = fw_file_size(file);
308         if (size < 0)
309                 return false;
310         buf = vmalloc(size);
311         if (!buf)
312                 return false;
313         if (kernel_read(file, 0, buf, size) != size) {
314                 vfree(buf);
315                 return false;
316         }
317         fw_buf->data = buf;
318         fw_buf->size = size;
319         return true;
320 }
321
322 static bool fw_get_filesystem_firmware(struct firmware_buf *buf)
323 {
324         int i;
325         bool success = false;
326         char *path = __getname();
327
328         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
329                 struct file *file;
330
331                 /* skip the unset customized path */
332                 if (!fw_path[i][0])
333                         continue;
334
335                 snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
336
337                 file = filp_open(path, O_RDONLY, 0);
338                 if (IS_ERR(file))
339                         continue;
340                 success = fw_read_file_contents(file, buf);
341                 fput(file);
342                 if (success)
343                         break;
344         }
345         __putname(path);
346         return success;
347 }
348
349 static struct firmware_priv *to_firmware_priv(struct device *dev)
350 {
351         return container_of(dev, struct firmware_priv, dev);
352 }
353
354 static void fw_load_abort(struct firmware_priv *fw_priv)
355 {
356         struct firmware_buf *buf = fw_priv->buf;
357
358         set_bit(FW_STATUS_ABORT, &buf->status);
359         complete_all(&buf->completion);
360 }
361
362 static ssize_t firmware_timeout_show(struct class *class,
363                                      struct class_attribute *attr,
364                                      char *buf)
365 {
366         return sprintf(buf, "%d\n", loading_timeout);
367 }
368
369 /**
370  * firmware_timeout_store - set number of seconds to wait for firmware
371  * @class: device class pointer
372  * @attr: device attribute pointer
373  * @buf: buffer to scan for timeout value
374  * @count: number of bytes in @buf
375  *
376  *      Sets the number of seconds to wait for the firmware.  Once
377  *      this expires an error will be returned to the driver and no
378  *      firmware will be provided.
379  *
380  *      Note: zero means 'wait forever'.
381  **/
382 static ssize_t firmware_timeout_store(struct class *class,
383                                       struct class_attribute *attr,
384                                       const char *buf, size_t count)
385 {
386         loading_timeout = simple_strtol(buf, NULL, 10);
387         if (loading_timeout < 0)
388                 loading_timeout = 0;
389
390         return count;
391 }
392
393 static struct class_attribute firmware_class_attrs[] = {
394         __ATTR(timeout, S_IWUSR | S_IRUGO,
395                 firmware_timeout_show, firmware_timeout_store),
396         __ATTR_NULL
397 };
398
399 static void fw_dev_release(struct device *dev)
400 {
401         struct firmware_priv *fw_priv = to_firmware_priv(dev);
402
403         kfree(fw_priv);
404
405         module_put(THIS_MODULE);
406 }
407
408 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
409 {
410         struct firmware_priv *fw_priv = to_firmware_priv(dev);
411
412         if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
413                 return -ENOMEM;
414         if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
415                 return -ENOMEM;
416         if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
417                 return -ENOMEM;
418
419         return 0;
420 }
421
422 static struct class firmware_class = {
423         .name           = "firmware",
424         .class_attrs    = firmware_class_attrs,
425         .dev_uevent     = firmware_uevent,
426         .dev_release    = fw_dev_release,
427 };
428
429 static ssize_t firmware_loading_show(struct device *dev,
430                                      struct device_attribute *attr, char *buf)
431 {
432         struct firmware_priv *fw_priv = to_firmware_priv(dev);
433         int loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
434
435         return sprintf(buf, "%d\n", loading);
436 }
437
438 /* firmware holds the ownership of pages */
439 static void firmware_free_data(const struct firmware *fw)
440 {
441         /* Loaded directly? */
442         if (!fw->priv) {
443                 vfree(fw->data);
444                 return;
445         }
446         fw_free_buf(fw->priv);
447 }
448
449 /* Some architectures don't have PAGE_KERNEL_RO */
450 #ifndef PAGE_KERNEL_RO
451 #define PAGE_KERNEL_RO PAGE_KERNEL
452 #endif
453
454 /* one pages buffer should be mapped/unmapped only once */
455 static int fw_map_pages_buf(struct firmware_buf *buf)
456 {
457         if (buf->fmt != PAGE_BUF)
458                 return 0;
459
460         if (buf->data)
461                 vunmap(buf->data);
462         buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
463         if (!buf->data)
464                 return -ENOMEM;
465         return 0;
466 }
467
468 /**
469  * firmware_loading_store - set value in the 'loading' control file
470  * @dev: device pointer
471  * @attr: device attribute pointer
472  * @buf: buffer to scan for loading control value
473  * @count: number of bytes in @buf
474  *
475  *      The relevant values are:
476  *
477  *       1: Start a load, discarding any previous partial load.
478  *       0: Conclude the load and hand the data to the driver code.
479  *      -1: Conclude the load with an error and discard any written data.
480  **/
481 static ssize_t firmware_loading_store(struct device *dev,
482                                       struct device_attribute *attr,
483                                       const char *buf, size_t count)
484 {
485         struct firmware_priv *fw_priv = to_firmware_priv(dev);
486         struct firmware_buf *fw_buf = fw_priv->buf;
487         int loading = simple_strtol(buf, NULL, 10);
488         int i;
489
490         mutex_lock(&fw_lock);
491
492         if (!fw_buf)
493                 goto out;
494
495         switch (loading) {
496         case 1:
497                 /* discarding any previous partial load */
498                 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
499                         for (i = 0; i < fw_buf->nr_pages; i++)
500                                 __free_page(fw_buf->pages[i]);
501                         kfree(fw_buf->pages);
502                         fw_buf->pages = NULL;
503                         fw_buf->page_array_size = 0;
504                         fw_buf->nr_pages = 0;
505                         set_bit(FW_STATUS_LOADING, &fw_buf->status);
506                 }
507                 break;
508         case 0:
509                 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
510                         set_bit(FW_STATUS_DONE, &fw_buf->status);
511                         clear_bit(FW_STATUS_LOADING, &fw_buf->status);
512
513                         /*
514                          * Several loading requests may be pending on
515                          * one same firmware buf, so let all requests
516                          * see the mapped 'buf->data' once the loading
517                          * is completed.
518                          * */
519                         fw_map_pages_buf(fw_buf);
520                         complete_all(&fw_buf->completion);
521                         break;
522                 }
523                 /* fallthrough */
524         default:
525                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
526                 /* fallthrough */
527         case -1:
528                 fw_load_abort(fw_priv);
529                 break;
530         }
531 out:
532         mutex_unlock(&fw_lock);
533         return count;
534 }
535
536 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
537
538 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
539                                   struct bin_attribute *bin_attr,
540                                   char *buffer, loff_t offset, size_t count)
541 {
542         struct device *dev = kobj_to_dev(kobj);
543         struct firmware_priv *fw_priv = to_firmware_priv(dev);
544         struct firmware_buf *buf;
545         ssize_t ret_count;
546
547         mutex_lock(&fw_lock);
548         buf = fw_priv->buf;
549         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
550                 ret_count = -ENODEV;
551                 goto out;
552         }
553         if (offset > buf->size) {
554                 ret_count = 0;
555                 goto out;
556         }
557         if (count > buf->size - offset)
558                 count = buf->size - offset;
559
560         ret_count = count;
561
562         while (count) {
563                 void *page_data;
564                 int page_nr = offset >> PAGE_SHIFT;
565                 int page_ofs = offset & (PAGE_SIZE-1);
566                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
567
568                 page_data = kmap(buf->pages[page_nr]);
569
570                 memcpy(buffer, page_data + page_ofs, page_cnt);
571
572                 kunmap(buf->pages[page_nr]);
573                 buffer += page_cnt;
574                 offset += page_cnt;
575                 count -= page_cnt;
576         }
577 out:
578         mutex_unlock(&fw_lock);
579         return ret_count;
580 }
581
582 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
583 {
584         struct firmware_buf *buf = fw_priv->buf;
585         int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
586
587         /* If the array of pages is too small, grow it... */
588         if (buf->page_array_size < pages_needed) {
589                 int new_array_size = max(pages_needed,
590                                          buf->page_array_size * 2);
591                 struct page **new_pages;
592
593                 new_pages = kmalloc(new_array_size * sizeof(void *),
594                                     GFP_KERNEL);
595                 if (!new_pages) {
596                         fw_load_abort(fw_priv);
597                         return -ENOMEM;
598                 }
599                 memcpy(new_pages, buf->pages,
600                        buf->page_array_size * sizeof(void *));
601                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
602                        (new_array_size - buf->page_array_size));
603                 kfree(buf->pages);
604                 buf->pages = new_pages;
605                 buf->page_array_size = new_array_size;
606         }
607
608         while (buf->nr_pages < pages_needed) {
609                 buf->pages[buf->nr_pages] =
610                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
611
612                 if (!buf->pages[buf->nr_pages]) {
613                         fw_load_abort(fw_priv);
614                         return -ENOMEM;
615                 }
616                 buf->nr_pages++;
617         }
618         return 0;
619 }
620
621 /**
622  * firmware_data_write - write method for firmware
623  * @filp: open sysfs file
624  * @kobj: kobject for the device
625  * @bin_attr: bin_attr structure
626  * @buffer: buffer being written
627  * @offset: buffer offset for write in total data store area
628  * @count: buffer size
629  *
630  *      Data written to the 'data' attribute will be later handed to
631  *      the driver as a firmware image.
632  **/
633 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
634                                    struct bin_attribute *bin_attr,
635                                    char *buffer, loff_t offset, size_t count)
636 {
637         struct device *dev = kobj_to_dev(kobj);
638         struct firmware_priv *fw_priv = to_firmware_priv(dev);
639         struct firmware_buf *buf;
640         ssize_t retval;
641
642         if (!capable(CAP_SYS_RAWIO))
643                 return -EPERM;
644
645         mutex_lock(&fw_lock);
646         buf = fw_priv->buf;
647         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
648                 retval = -ENODEV;
649                 goto out;
650         }
651
652         retval = fw_realloc_buffer(fw_priv, offset + count);
653         if (retval)
654                 goto out;
655
656         retval = count;
657
658         while (count) {
659                 void *page_data;
660                 int page_nr = offset >> PAGE_SHIFT;
661                 int page_ofs = offset & (PAGE_SIZE - 1);
662                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
663
664                 page_data = kmap(buf->pages[page_nr]);
665
666                 memcpy(page_data + page_ofs, buffer, page_cnt);
667
668                 kunmap(buf->pages[page_nr]);
669                 buffer += page_cnt;
670                 offset += page_cnt;
671                 count -= page_cnt;
672         }
673
674         buf->size = max_t(size_t, offset, buf->size);
675 out:
676         mutex_unlock(&fw_lock);
677         return retval;
678 }
679
680 static struct bin_attribute firmware_attr_data = {
681         .attr = { .name = "data", .mode = 0644 },
682         .size = 0,
683         .read = firmware_data_read,
684         .write = firmware_data_write,
685 };
686
687 static void firmware_class_timeout_work(struct work_struct *work)
688 {
689         struct firmware_priv *fw_priv = container_of(work,
690                         struct firmware_priv, timeout_work.work);
691
692         mutex_lock(&fw_lock);
693         if (test_bit(FW_STATUS_DONE, &(fw_priv->buf->status))) {
694                 mutex_unlock(&fw_lock);
695                 return;
696         }
697         fw_load_abort(fw_priv);
698         mutex_unlock(&fw_lock);
699 }
700
701 static struct firmware_priv *
702 fw_create_instance(struct firmware *firmware, const char *fw_name,
703                    struct device *device, bool uevent, bool nowait)
704 {
705         struct firmware_priv *fw_priv;
706         struct device *f_dev;
707
708         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
709         if (!fw_priv) {
710                 dev_err(device, "%s: kmalloc failed\n", __func__);
711                 fw_priv = ERR_PTR(-ENOMEM);
712                 goto exit;
713         }
714
715         fw_priv->nowait = nowait;
716         fw_priv->fw = firmware;
717         INIT_DELAYED_WORK(&fw_priv->timeout_work,
718                 firmware_class_timeout_work);
719
720         f_dev = &fw_priv->dev;
721
722         device_initialize(f_dev);
723         dev_set_name(f_dev, "%s", fw_name);
724         f_dev->parent = device;
725         f_dev->class = &firmware_class;
726 exit:
727         return fw_priv;
728 }
729
730 /* store the pages buffer info firmware from buf */
731 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
732 {
733         fw->priv = buf;
734         fw->pages = buf->pages;
735         fw->size = buf->size;
736         fw->data = buf->data;
737
738         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
739                  __func__, buf->fw_id, buf, buf->data,
740                  (unsigned int)buf->size);
741 }
742
743 #ifdef CONFIG_PM_SLEEP
744 static void fw_name_devm_release(struct device *dev, void *res)
745 {
746         struct fw_name_devm *fwn = res;
747
748         if (fwn->magic == (unsigned long)&fw_cache)
749                 pr_debug("%s: fw_name-%s devm-%p released\n",
750                                 __func__, fwn->name, res);
751 }
752
753 static int fw_devm_match(struct device *dev, void *res,
754                 void *match_data)
755 {
756         struct fw_name_devm *fwn = res;
757
758         return (fwn->magic == (unsigned long)&fw_cache) &&
759                 !strcmp(fwn->name, match_data);
760 }
761
762 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
763                 const char *name)
764 {
765         struct fw_name_devm *fwn;
766
767         fwn = devres_find(dev, fw_name_devm_release,
768                           fw_devm_match, (void *)name);
769         return fwn;
770 }
771
772 /* add firmware name into devres list */
773 static int fw_add_devm_name(struct device *dev, const char *name)
774 {
775         struct fw_name_devm *fwn;
776
777         fwn = fw_find_devm_name(dev, name);
778         if (fwn)
779                 return 1;
780
781         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
782                            strlen(name) + 1, GFP_KERNEL);
783         if (!fwn)
784                 return -ENOMEM;
785
786         fwn->magic = (unsigned long)&fw_cache;
787         strcpy(fwn->name, name);
788         devres_add(dev, fwn);
789
790         return 0;
791 }
792 #else
793 static int fw_add_devm_name(struct device *dev, const char *name)
794 {
795         return 0;
796 }
797 #endif
798
799 static void _request_firmware_cleanup(const struct firmware **firmware_p)
800 {
801         release_firmware(*firmware_p);
802         *firmware_p = NULL;
803 }
804
805 static struct firmware_priv *
806 _request_firmware_prepare(const struct firmware **firmware_p, const char *name,
807                           struct device *device, bool uevent, bool nowait)
808 {
809         struct firmware *firmware;
810         struct firmware_priv *fw_priv = NULL;
811         struct firmware_buf *buf;
812         int ret;
813
814         if (!firmware_p)
815                 return ERR_PTR(-EINVAL);
816
817         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
818         if (!firmware) {
819                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
820                         __func__);
821                 return ERR_PTR(-ENOMEM);
822         }
823
824         if (fw_get_builtin_firmware(firmware, name)) {
825                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
826                 return NULL;
827         }
828
829         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
830         if (!ret)
831                 fw_priv = fw_create_instance(firmware, name, device,
832                                 uevent, nowait);
833
834         if (IS_ERR(fw_priv) || ret < 0) {
835                 kfree(firmware);
836                 *firmware_p = NULL;
837                 return ERR_PTR(-ENOMEM);
838         } else if (fw_priv) {
839                 fw_priv->buf = buf;
840
841                 /*
842                  * bind with 'buf' now to avoid warning in failure path
843                  * of requesting firmware.
844                  */
845                 firmware->priv = buf;
846                 return fw_priv;
847         }
848
849         /* share the cached buf, which is inprogessing or completed */
850  check_status:
851         mutex_lock(&fw_lock);
852         if (test_bit(FW_STATUS_ABORT, &buf->status)) {
853                 fw_priv = ERR_PTR(-ENOENT);
854                 firmware->priv = buf;
855                 _request_firmware_cleanup(firmware_p);
856                 goto exit;
857         } else if (test_bit(FW_STATUS_DONE, &buf->status)) {
858                 fw_priv = NULL;
859                 fw_set_page_data(buf, firmware);
860                 goto exit;
861         }
862         mutex_unlock(&fw_lock);
863         wait_for_completion(&buf->completion);
864         goto check_status;
865
866 exit:
867         mutex_unlock(&fw_lock);
868         return fw_priv;
869 }
870
871 static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
872                                   long timeout)
873 {
874         int retval = 0;
875         struct device *f_dev = &fw_priv->dev;
876         struct firmware_buf *buf = fw_priv->buf;
877         struct firmware_cache *fwc = &fw_cache;
878         int direct_load = 0;
879
880         /* try direct loading from fs first */
881         if (fw_get_filesystem_firmware(buf)) {
882                 dev_dbg(f_dev->parent, "firmware: direct-loading"
883                         " firmware %s\n", buf->fw_id);
884
885                 mutex_lock(&fw_lock);
886                 set_bit(FW_STATUS_DONE, &buf->status);
887                 mutex_unlock(&fw_lock);
888                 complete_all(&buf->completion);
889                 direct_load = 1;
890                 goto handle_fw;
891         }
892
893         /* fall back on userspace loading */
894         buf->fmt = PAGE_BUF;
895
896         dev_set_uevent_suppress(f_dev, true);
897
898         /* Need to pin this module until class device is destroyed */
899         __module_get(THIS_MODULE);
900
901         retval = device_add(f_dev);
902         if (retval) {
903                 dev_err(f_dev, "%s: device_register failed\n", __func__);
904                 goto err_put_dev;
905         }
906
907         retval = device_create_bin_file(f_dev, &firmware_attr_data);
908         if (retval) {
909                 dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
910                 goto err_del_dev;
911         }
912
913         retval = device_create_file(f_dev, &dev_attr_loading);
914         if (retval) {
915                 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
916                 goto err_del_bin_attr;
917         }
918
919         if (uevent) {
920                 dev_set_uevent_suppress(f_dev, false);
921                 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
922                 if (timeout != MAX_SCHEDULE_TIMEOUT)
923                         schedule_delayed_work(&fw_priv->timeout_work, timeout);
924
925                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
926         }
927
928         wait_for_completion(&buf->completion);
929
930         cancel_delayed_work_sync(&fw_priv->timeout_work);
931
932 handle_fw:
933         mutex_lock(&fw_lock);
934         if (!buf->size || test_bit(FW_STATUS_ABORT, &buf->status))
935                 retval = -ENOENT;
936
937         /*
938          * add firmware name into devres list so that we can auto cache
939          * and uncache firmware for device.
940          *
941          * f_dev->parent may has been deleted already, but the problem
942          * should be fixed in devres or driver core.
943          */
944         if (!retval && f_dev->parent)
945                 fw_add_devm_name(f_dev->parent, buf->fw_id);
946
947         /*
948          * After caching firmware image is started, let it piggyback
949          * on request firmware.
950          */
951         if (!retval && fwc->state == FW_LOADER_START_CACHE) {
952                 if (fw_cache_piggyback_on_request(buf->fw_id))
953                         kref_get(&buf->ref);
954         }
955
956         /* pass the pages buffer to driver at the last minute */
957         fw_set_page_data(buf, fw_priv->fw);
958
959         fw_priv->buf = NULL;
960         mutex_unlock(&fw_lock);
961
962         if (direct_load)
963                 goto err_put_dev;
964
965         device_remove_file(f_dev, &dev_attr_loading);
966 err_del_bin_attr:
967         device_remove_bin_file(f_dev, &firmware_attr_data);
968 err_del_dev:
969         device_del(f_dev);
970 err_put_dev:
971         put_device(f_dev);
972         return retval;
973 }
974
975 /**
976  * request_firmware: - send firmware request and wait for it
977  * @firmware_p: pointer to firmware image
978  * @name: name of firmware file
979  * @device: device for which firmware is being loaded
980  *
981  *      @firmware_p will be used to return a firmware image by the name
982  *      of @name for device @device.
983  *
984  *      Should be called from user context where sleeping is allowed.
985  *
986  *      @name will be used as $FIRMWARE in the uevent environment and
987  *      should be distinctive enough not to be confused with any other
988  *      firmware image for this or any other device.
989  *
990  *      Caller must hold the reference count of @device.
991  **/
992 int
993 request_firmware(const struct firmware **firmware_p, const char *name,
994                  struct device *device)
995 {
996         struct firmware_priv *fw_priv;
997         int ret;
998
999         fw_priv = _request_firmware_prepare(firmware_p, name, device, true,
1000                                             false);
1001         if (IS_ERR_OR_NULL(fw_priv))
1002                 return PTR_RET(fw_priv);
1003
1004         ret = usermodehelper_read_trylock();
1005         if (WARN_ON(ret)) {
1006                 dev_err(device, "firmware: %s will not be loaded\n", name);
1007         } else {
1008                 ret = _request_firmware_load(fw_priv, true,
1009                                         firmware_loading_timeout());
1010                 usermodehelper_read_unlock();
1011         }
1012         if (ret)
1013                 _request_firmware_cleanup(firmware_p);
1014
1015         return ret;
1016 }
1017
1018 /**
1019  * release_firmware: - release the resource associated with a firmware image
1020  * @fw: firmware resource to release
1021  **/
1022 void release_firmware(const struct firmware *fw)
1023 {
1024         if (fw) {
1025                 if (!fw_is_builtin_firmware(fw))
1026                         firmware_free_data(fw);
1027                 kfree(fw);
1028         }
1029 }
1030
1031 /* Async support */
1032 struct firmware_work {
1033         struct work_struct work;
1034         struct module *module;
1035         const char *name;
1036         struct device *device;
1037         void *context;
1038         void (*cont)(const struct firmware *fw, void *context);
1039         bool uevent;
1040 };
1041
1042 static void request_firmware_work_func(struct work_struct *work)
1043 {
1044         struct firmware_work *fw_work;
1045         const struct firmware *fw;
1046         struct firmware_priv *fw_priv;
1047         long timeout;
1048         int ret;
1049
1050         fw_work = container_of(work, struct firmware_work, work);
1051         fw_priv = _request_firmware_prepare(&fw, fw_work->name, fw_work->device,
1052                         fw_work->uevent, true);
1053         if (IS_ERR_OR_NULL(fw_priv)) {
1054                 ret = PTR_RET(fw_priv);
1055                 goto out;
1056         }
1057
1058         timeout = usermodehelper_read_lock_wait(firmware_loading_timeout());
1059         if (timeout) {
1060                 ret = _request_firmware_load(fw_priv, fw_work->uevent, timeout);
1061                 usermodehelper_read_unlock();
1062         } else {
1063                 dev_dbg(fw_work->device, "firmware: %s loading timed out\n",
1064                         fw_work->name);
1065                 ret = -EAGAIN;
1066         }
1067         if (ret)
1068                 _request_firmware_cleanup(&fw);
1069
1070  out:
1071         fw_work->cont(fw, fw_work->context);
1072         put_device(fw_work->device);
1073
1074         module_put(fw_work->module);
1075         kfree(fw_work);
1076 }
1077
1078 /**
1079  * request_firmware_nowait - asynchronous version of request_firmware
1080  * @module: module requesting the firmware
1081  * @uevent: sends uevent to copy the firmware image if this flag
1082  *      is non-zero else the firmware copy must be done manually.
1083  * @name: name of firmware file
1084  * @device: device for which firmware is being loaded
1085  * @gfp: allocation flags
1086  * @context: will be passed over to @cont, and
1087  *      @fw may be %NULL if firmware request fails.
1088  * @cont: function will be called asynchronously when the firmware
1089  *      request is over.
1090  *
1091  *      Caller must hold the reference count of @device.
1092  *
1093  *      Asynchronous variant of request_firmware() for user contexts:
1094  *              - sleep for as small periods as possible since it may
1095  *              increase kernel boot time of built-in device drivers
1096  *              requesting firmware in their ->probe() methods, if
1097  *              @gfp is GFP_KERNEL.
1098  *
1099  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1100  **/
1101 int
1102 request_firmware_nowait(
1103         struct module *module, bool uevent,
1104         const char *name, struct device *device, gfp_t gfp, void *context,
1105         void (*cont)(const struct firmware *fw, void *context))
1106 {
1107         struct firmware_work *fw_work;
1108
1109         fw_work = kzalloc(sizeof (struct firmware_work), gfp);
1110         if (!fw_work)
1111                 return -ENOMEM;
1112
1113         fw_work->module = module;
1114         fw_work->name = name;
1115         fw_work->device = device;
1116         fw_work->context = context;
1117         fw_work->cont = cont;
1118         fw_work->uevent = uevent;
1119
1120         if (!try_module_get(module)) {
1121                 kfree(fw_work);
1122                 return -EFAULT;
1123         }
1124
1125         get_device(fw_work->device);
1126         INIT_WORK(&fw_work->work, request_firmware_work_func);
1127         schedule_work(&fw_work->work);
1128         return 0;
1129 }
1130
1131 /**
1132  * cache_firmware - cache one firmware image in kernel memory space
1133  * @fw_name: the firmware image name
1134  *
1135  * Cache firmware in kernel memory so that drivers can use it when
1136  * system isn't ready for them to request firmware image from userspace.
1137  * Once it returns successfully, driver can use request_firmware or its
1138  * nowait version to get the cached firmware without any interacting
1139  * with userspace
1140  *
1141  * Return 0 if the firmware image has been cached successfully
1142  * Return !0 otherwise
1143  *
1144  */
1145 int cache_firmware(const char *fw_name)
1146 {
1147         int ret;
1148         const struct firmware *fw;
1149
1150         pr_debug("%s: %s\n", __func__, fw_name);
1151
1152         ret = request_firmware(&fw, fw_name, NULL);
1153         if (!ret)
1154                 kfree(fw);
1155
1156         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1157
1158         return ret;
1159 }
1160
1161 /**
1162  * uncache_firmware - remove one cached firmware image
1163  * @fw_name: the firmware image name
1164  *
1165  * Uncache one firmware image which has been cached successfully
1166  * before.
1167  *
1168  * Return 0 if the firmware cache has been removed successfully
1169  * Return !0 otherwise
1170  *
1171  */
1172 int uncache_firmware(const char *fw_name)
1173 {
1174         struct firmware_buf *buf;
1175         struct firmware fw;
1176
1177         pr_debug("%s: %s\n", __func__, fw_name);
1178
1179         if (fw_get_builtin_firmware(&fw, fw_name))
1180                 return 0;
1181
1182         buf = fw_lookup_buf(fw_name);
1183         if (buf) {
1184                 fw_free_buf(buf);
1185                 return 0;
1186         }
1187
1188         return -EINVAL;
1189 }
1190
1191 #ifdef CONFIG_PM_SLEEP
1192 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1193
1194 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1195 {
1196         struct fw_cache_entry *fce;
1197
1198         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1199         if (!fce)
1200                 goto exit;
1201
1202         strcpy(fce->name, name);
1203 exit:
1204         return fce;
1205 }
1206
1207 static int __fw_entry_found(const char *name)
1208 {
1209         struct firmware_cache *fwc = &fw_cache;
1210         struct fw_cache_entry *fce;
1211
1212         list_for_each_entry(fce, &fwc->fw_names, list) {
1213                 if (!strcmp(fce->name, name))
1214                         return 1;
1215         }
1216         return 0;
1217 }
1218
1219 static int fw_cache_piggyback_on_request(const char *name)
1220 {
1221         struct firmware_cache *fwc = &fw_cache;
1222         struct fw_cache_entry *fce;
1223         int ret = 0;
1224
1225         spin_lock(&fwc->name_lock);
1226         if (__fw_entry_found(name))
1227                 goto found;
1228
1229         fce = alloc_fw_cache_entry(name);
1230         if (fce) {
1231                 ret = 1;
1232                 list_add(&fce->list, &fwc->fw_names);
1233                 pr_debug("%s: fw: %s\n", __func__, name);
1234         }
1235 found:
1236         spin_unlock(&fwc->name_lock);
1237         return ret;
1238 }
1239
1240 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1241 {
1242         kfree(fce);
1243 }
1244
1245 static void __async_dev_cache_fw_image(void *fw_entry,
1246                                        async_cookie_t cookie)
1247 {
1248         struct fw_cache_entry *fce = fw_entry;
1249         struct firmware_cache *fwc = &fw_cache;
1250         int ret;
1251
1252         ret = cache_firmware(fce->name);
1253         if (ret) {
1254                 spin_lock(&fwc->name_lock);
1255                 list_del(&fce->list);
1256                 spin_unlock(&fwc->name_lock);
1257
1258                 free_fw_cache_entry(fce);
1259         }
1260 }
1261
1262 /* called with dev->devres_lock held */
1263 static void dev_create_fw_entry(struct device *dev, void *res,
1264                                 void *data)
1265 {
1266         struct fw_name_devm *fwn = res;
1267         const char *fw_name = fwn->name;
1268         struct list_head *head = data;
1269         struct fw_cache_entry *fce;
1270
1271         fce = alloc_fw_cache_entry(fw_name);
1272         if (fce)
1273                 list_add(&fce->list, head);
1274 }
1275
1276 static int devm_name_match(struct device *dev, void *res,
1277                            void *match_data)
1278 {
1279         struct fw_name_devm *fwn = res;
1280         return (fwn->magic == (unsigned long)match_data);
1281 }
1282
1283 static void dev_cache_fw_image(struct device *dev, void *data)
1284 {
1285         LIST_HEAD(todo);
1286         struct fw_cache_entry *fce;
1287         struct fw_cache_entry *fce_next;
1288         struct firmware_cache *fwc = &fw_cache;
1289
1290         devres_for_each_res(dev, fw_name_devm_release,
1291                             devm_name_match, &fw_cache,
1292                             dev_create_fw_entry, &todo);
1293
1294         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1295                 list_del(&fce->list);
1296
1297                 spin_lock(&fwc->name_lock);
1298                 /* only one cache entry for one firmware */
1299                 if (!__fw_entry_found(fce->name)) {
1300                         list_add(&fce->list, &fwc->fw_names);
1301                 } else {
1302                         free_fw_cache_entry(fce);
1303                         fce = NULL;
1304                 }
1305                 spin_unlock(&fwc->name_lock);
1306
1307                 if (fce)
1308                         async_schedule_domain(__async_dev_cache_fw_image,
1309                                               (void *)fce,
1310                                               &fw_cache_domain);
1311         }
1312 }
1313
1314 static void __device_uncache_fw_images(void)
1315 {
1316         struct firmware_cache *fwc = &fw_cache;
1317         struct fw_cache_entry *fce;
1318
1319         spin_lock(&fwc->name_lock);
1320         while (!list_empty(&fwc->fw_names)) {
1321                 fce = list_entry(fwc->fw_names.next,
1322                                 struct fw_cache_entry, list);
1323                 list_del(&fce->list);
1324                 spin_unlock(&fwc->name_lock);
1325
1326                 uncache_firmware(fce->name);
1327                 free_fw_cache_entry(fce);
1328
1329                 spin_lock(&fwc->name_lock);
1330         }
1331         spin_unlock(&fwc->name_lock);
1332 }
1333
1334 /**
1335  * device_cache_fw_images - cache devices' firmware
1336  *
1337  * If one device called request_firmware or its nowait version
1338  * successfully before, the firmware names are recored into the
1339  * device's devres link list, so device_cache_fw_images can call
1340  * cache_firmware() to cache these firmwares for the device,
1341  * then the device driver can load its firmwares easily at
1342  * time when system is not ready to complete loading firmware.
1343  */
1344 static void device_cache_fw_images(void)
1345 {
1346         struct firmware_cache *fwc = &fw_cache;
1347         int old_timeout;
1348         DEFINE_WAIT(wait);
1349
1350         pr_debug("%s\n", __func__);
1351
1352         /* cancel uncache work */
1353         cancel_delayed_work_sync(&fwc->work);
1354
1355         /*
1356          * use small loading timeout for caching devices' firmware
1357          * because all these firmware images have been loaded
1358          * successfully at lease once, also system is ready for
1359          * completing firmware loading now. The maximum size of
1360          * firmware in current distributions is about 2M bytes,
1361          * so 10 secs should be enough.
1362          */
1363         old_timeout = loading_timeout;
1364         loading_timeout = 10;
1365
1366         mutex_lock(&fw_lock);
1367         fwc->state = FW_LOADER_START_CACHE;
1368         dpm_for_each_dev(NULL, dev_cache_fw_image);
1369         mutex_unlock(&fw_lock);
1370
1371         /* wait for completion of caching firmware for all devices */
1372         async_synchronize_full_domain(&fw_cache_domain);
1373
1374         loading_timeout = old_timeout;
1375 }
1376
1377 /**
1378  * device_uncache_fw_images - uncache devices' firmware
1379  *
1380  * uncache all firmwares which have been cached successfully
1381  * by device_uncache_fw_images earlier
1382  */
1383 static void device_uncache_fw_images(void)
1384 {
1385         pr_debug("%s\n", __func__);
1386         __device_uncache_fw_images();
1387 }
1388
1389 static void device_uncache_fw_images_work(struct work_struct *work)
1390 {
1391         device_uncache_fw_images();
1392 }
1393
1394 /**
1395  * device_uncache_fw_images_delay - uncache devices firmwares
1396  * @delay: number of milliseconds to delay uncache device firmwares
1397  *
1398  * uncache all devices's firmwares which has been cached successfully
1399  * by device_cache_fw_images after @delay milliseconds.
1400  */
1401 static void device_uncache_fw_images_delay(unsigned long delay)
1402 {
1403         schedule_delayed_work(&fw_cache.work,
1404                         msecs_to_jiffies(delay));
1405 }
1406
1407 static int fw_pm_notify(struct notifier_block *notify_block,
1408                         unsigned long mode, void *unused)
1409 {
1410         switch (mode) {
1411         case PM_HIBERNATION_PREPARE:
1412         case PM_SUSPEND_PREPARE:
1413                 device_cache_fw_images();
1414                 break;
1415
1416         case PM_POST_SUSPEND:
1417         case PM_POST_HIBERNATION:
1418         case PM_POST_RESTORE:
1419                 /*
1420                  * In case that system sleep failed and syscore_suspend is
1421                  * not called.
1422                  */
1423                 mutex_lock(&fw_lock);
1424                 fw_cache.state = FW_LOADER_NO_CACHE;
1425                 mutex_unlock(&fw_lock);
1426
1427                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1428                 break;
1429         }
1430
1431         return 0;
1432 }
1433
1434 /* stop caching firmware once syscore_suspend is reached */
1435 static int fw_suspend(void)
1436 {
1437         fw_cache.state = FW_LOADER_NO_CACHE;
1438         return 0;
1439 }
1440
1441 static struct syscore_ops fw_syscore_ops = {
1442         .suspend = fw_suspend,
1443 };
1444 #else
1445 static int fw_cache_piggyback_on_request(const char *name)
1446 {
1447         return 0;
1448 }
1449 #endif
1450
1451 static void __init fw_cache_init(void)
1452 {
1453         spin_lock_init(&fw_cache.lock);
1454         INIT_LIST_HEAD(&fw_cache.head);
1455         fw_cache.state = FW_LOADER_NO_CACHE;
1456
1457 #ifdef CONFIG_PM_SLEEP
1458         spin_lock_init(&fw_cache.name_lock);
1459         INIT_LIST_HEAD(&fw_cache.fw_names);
1460
1461         INIT_DELAYED_WORK(&fw_cache.work,
1462                           device_uncache_fw_images_work);
1463
1464         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1465         register_pm_notifier(&fw_cache.pm_notify);
1466
1467         register_syscore_ops(&fw_syscore_ops);
1468 #endif
1469 }
1470
1471 static int __init firmware_class_init(void)
1472 {
1473         fw_cache_init();
1474         return class_register(&firmware_class);
1475 }
1476
1477 static void __exit firmware_class_exit(void)
1478 {
1479 #ifdef CONFIG_PM_SLEEP
1480         unregister_syscore_ops(&fw_syscore_ops);
1481         unregister_pm_notifier(&fw_cache.pm_notify);
1482 #endif
1483         class_unregister(&firmware_class);
1484 }
1485
1486 fs_initcall(firmware_class_init);
1487 module_exit(firmware_class_exit);
1488
1489 EXPORT_SYMBOL(release_firmware);
1490 EXPORT_SYMBOL(request_firmware);
1491 EXPORT_SYMBOL(request_firmware_nowait);
1492 EXPORT_SYMBOL_GPL(cache_firmware);
1493 EXPORT_SYMBOL_GPL(uncache_firmware);