2 * firmware_class.c - Multi purpose firmware loading support
4 * Copyright (c) 2003 Manuel Estrada Sainz
6 * Please see Documentation/firmware_class/ for more information.
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>
27 #include <linux/async.h>
29 #include <linux/suspend.h>
30 #include <linux/syscore_ops.h>
31 #include <linux/reboot.h>
32 #include <linux/security.h>
33 #include <linux/swait.h>
35 #include <generated/utsrelease.h>
39 MODULE_AUTHOR("Manuel Estrada Sainz");
40 MODULE_DESCRIPTION("Multi purpose firmware loading support");
41 MODULE_LICENSE("GPL");
43 /* Builtin firmware support */
45 #ifdef CONFIG_FW_LOADER
47 extern struct builtin_fw __start_builtin_fw[];
48 extern struct builtin_fw __end_builtin_fw[];
50 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,
51 void *buf, size_t size)
53 struct builtin_fw *b_fw;
55 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
56 if (strcmp(name, b_fw->name) == 0) {
57 fw->size = b_fw->size;
58 fw->data = b_fw->data;
60 if (buf && fw->size <= size)
61 memcpy(buf, fw->data, fw->size);
69 static bool fw_is_builtin_firmware(const struct firmware *fw)
71 struct builtin_fw *b_fw;
73 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
74 if (fw->data == b_fw->data)
80 #else /* Module case - no builtin firmware support */
82 static inline bool fw_get_builtin_firmware(struct firmware *fw,
83 const char *name, void *buf,
89 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
102 static int loading_timeout = 60; /* In seconds */
104 static inline long firmware_loading_timeout(void)
106 return loading_timeout > 0 ? loading_timeout * HZ : MAX_JIFFY_OFFSET;
110 * Concurrent request_firmware() for the same firmware need to be
111 * serialized. struct fw_state is simple state machine which hold the
112 * state of the firmware loading.
115 struct swait_queue_head wq;
116 enum fw_status status;
119 static void fw_state_init(struct fw_state *fw_st)
121 init_swait_queue_head(&fw_st->wq);
122 fw_st->status = FW_STATUS_UNKNOWN;
125 static inline bool __fw_state_is_done(enum fw_status status)
127 return status == FW_STATUS_DONE || status == FW_STATUS_ABORTED;
130 static int __fw_state_wait_common(struct fw_state *fw_st, long timeout)
134 ret = swait_event_interruptible_timeout(fw_st->wq,
135 __fw_state_is_done(READ_ONCE(fw_st->status)),
137 if (ret != 0 && fw_st->status == FW_STATUS_ABORTED)
142 return ret < 0 ? ret : 0;
145 static void __fw_state_set(struct fw_state *fw_st,
146 enum fw_status status)
148 WRITE_ONCE(fw_st->status, status);
150 if (status == FW_STATUS_DONE || status == FW_STATUS_ABORTED)
151 swake_up(&fw_st->wq);
154 #define fw_state_start(fw_st) \
155 __fw_state_set(fw_st, FW_STATUS_LOADING)
156 #define fw_state_done(fw_st) \
157 __fw_state_set(fw_st, FW_STATUS_DONE)
158 #define fw_state_wait(fw_st) \
159 __fw_state_wait_common(fw_st, MAX_SCHEDULE_TIMEOUT)
161 #ifndef CONFIG_FW_LOADER_USER_HELPER
163 #define fw_state_is_aborted(fw_st) false
165 #else /* CONFIG_FW_LOADER_USER_HELPER */
167 static int __fw_state_check(struct fw_state *fw_st, enum fw_status status)
169 return fw_st->status == status;
172 #define fw_state_aborted(fw_st) \
173 __fw_state_set(fw_st, FW_STATUS_ABORTED)
174 #define fw_state_is_done(fw_st) \
175 __fw_state_check(fw_st, FW_STATUS_DONE)
176 #define fw_state_is_loading(fw_st) \
177 __fw_state_check(fw_st, FW_STATUS_LOADING)
178 #define fw_state_is_aborted(fw_st) \
179 __fw_state_check(fw_st, FW_STATUS_ABORTED)
180 #define fw_state_wait_timeout(fw_st, timeout) \
181 __fw_state_wait_common(fw_st, timeout)
183 #endif /* CONFIG_FW_LOADER_USER_HELPER */
185 /* firmware behavior options */
186 #define FW_OPT_UEVENT (1U << 0)
187 #define FW_OPT_NOWAIT (1U << 1)
188 #ifdef CONFIG_FW_LOADER_USER_HELPER
189 #define FW_OPT_USERHELPER (1U << 2)
191 #define FW_OPT_USERHELPER 0
193 #ifdef CONFIG_FW_LOADER_USER_HELPER_FALLBACK
194 #define FW_OPT_FALLBACK FW_OPT_USERHELPER
196 #define FW_OPT_FALLBACK 0
198 #define FW_OPT_NO_WARN (1U << 3)
199 #define FW_OPT_NOCACHE (1U << 4)
201 struct firmware_cache {
202 /* firmware_buf instance will be added into the below list */
204 struct list_head head;
207 #ifdef CONFIG_PM_SLEEP
209 * Names of firmware images which have been cached successfully
210 * will be added into the below list so that device uncache
211 * helper can trace which firmware images have been cached
214 spinlock_t name_lock;
215 struct list_head fw_names;
217 struct delayed_work work;
219 struct notifier_block pm_notify;
223 struct firmware_buf {
225 struct list_head list;
226 struct firmware_cache *fwc;
227 struct fw_state fw_st;
230 size_t allocated_size;
231 #ifdef CONFIG_FW_LOADER_USER_HELPER
237 struct list_head pending_list;
242 struct fw_cache_entry {
243 struct list_head list;
247 struct fw_name_devm {
252 #define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
254 #define FW_LOADER_NO_CACHE 0
255 #define FW_LOADER_START_CACHE 1
257 static int fw_cache_piggyback_on_request(const char *name);
259 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
260 * guarding for corner cases a global lock should be OK */
261 static DEFINE_MUTEX(fw_lock);
263 static bool __enable_firmware = false;
265 static void enable_firmware(void)
267 mutex_lock(&fw_lock);
268 __enable_firmware = true;
269 mutex_unlock(&fw_lock);
272 static void disable_firmware(void)
274 mutex_lock(&fw_lock);
275 __enable_firmware = false;
276 mutex_unlock(&fw_lock);
280 * When disabled only the built-in firmware and the firmware cache will be
281 * used to look for firmware.
283 static bool firmware_enabled(void)
285 bool enabled = false;
287 mutex_lock(&fw_lock);
288 if (__enable_firmware)
290 mutex_unlock(&fw_lock);
295 static struct firmware_cache fw_cache;
297 static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
298 struct firmware_cache *fwc,
299 void *dbuf, size_t size)
301 struct firmware_buf *buf;
303 buf = kzalloc(sizeof(*buf), GFP_ATOMIC);
307 buf->fw_id = kstrdup_const(fw_name, GFP_ATOMIC);
313 kref_init(&buf->ref);
316 buf->allocated_size = size;
317 fw_state_init(&buf->fw_st);
318 #ifdef CONFIG_FW_LOADER_USER_HELPER
319 INIT_LIST_HEAD(&buf->pending_list);
322 pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
327 static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
329 struct firmware_buf *tmp;
330 struct firmware_cache *fwc = &fw_cache;
332 list_for_each_entry(tmp, &fwc->head, list)
333 if (!strcmp(tmp->fw_id, fw_name))
338 static int fw_lookup_and_allocate_buf(const char *fw_name,
339 struct firmware_cache *fwc,
340 struct firmware_buf **buf, void *dbuf,
343 struct firmware_buf *tmp;
345 spin_lock(&fwc->lock);
346 tmp = __fw_lookup_buf(fw_name);
349 spin_unlock(&fwc->lock);
353 tmp = __allocate_fw_buf(fw_name, fwc, dbuf, size);
355 list_add(&tmp->list, &fwc->head);
356 spin_unlock(&fwc->lock);
360 return tmp ? 0 : -ENOMEM;
363 static void __fw_free_buf(struct kref *ref)
364 __releases(&fwc->lock)
366 struct firmware_buf *buf = to_fwbuf(ref);
367 struct firmware_cache *fwc = buf->fwc;
369 pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
370 __func__, buf->fw_id, buf, buf->data,
371 (unsigned int)buf->size);
373 list_del(&buf->list);
374 spin_unlock(&fwc->lock);
376 #ifdef CONFIG_FW_LOADER_USER_HELPER
377 if (buf->is_paged_buf) {
380 for (i = 0; i < buf->nr_pages; i++)
381 __free_page(buf->pages[i]);
385 if (!buf->allocated_size)
387 kfree_const(buf->fw_id);
391 static void fw_free_buf(struct firmware_buf *buf)
393 struct firmware_cache *fwc = buf->fwc;
394 spin_lock(&fwc->lock);
395 if (!kref_put(&buf->ref, __fw_free_buf))
396 spin_unlock(&fwc->lock);
399 /* direct firmware loading support */
400 static char fw_path_para[256];
401 static const char * const fw_path[] = {
403 "/lib/firmware/updates/" UTS_RELEASE,
404 "/lib/firmware/updates",
405 "/lib/firmware/" UTS_RELEASE,
410 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
411 * from kernel command line because firmware_class is generally built in
412 * kernel instead of module.
414 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
415 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
418 fw_get_filesystem_firmware(struct device *device, struct firmware_buf *buf)
424 enum kernel_read_file_id id = READING_FIRMWARE;
425 size_t msize = INT_MAX;
427 /* Already populated data member means we're loading into a buffer */
429 id = READING_FIRMWARE_PREALLOC_BUFFER;
430 msize = buf->allocated_size;
437 for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
438 /* skip the unset customized path */
442 len = snprintf(path, PATH_MAX, "%s/%s",
443 fw_path[i], buf->fw_id);
444 if (len >= PATH_MAX) {
450 rc = kernel_read_file_from_path(path, &buf->data, &size, msize,
454 dev_dbg(device, "loading %s failed with error %d\n",
457 dev_warn(device, "loading %s failed with error %d\n",
461 dev_dbg(device, "direct-loading %s\n", buf->fw_id);
463 fw_state_done(&buf->fw_st);
471 /* firmware holds the ownership of pages */
472 static void firmware_free_data(const struct firmware *fw)
474 /* Loaded directly? */
479 fw_free_buf(fw->priv);
482 /* store the pages buffer info firmware from buf */
483 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
486 #ifdef CONFIG_FW_LOADER_USER_HELPER
487 fw->pages = buf->pages;
489 fw->size = buf->size;
490 fw->data = buf->data;
492 pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
493 __func__, buf->fw_id, buf, buf->data,
494 (unsigned int)buf->size);
497 #ifdef CONFIG_PM_SLEEP
498 static void fw_name_devm_release(struct device *dev, void *res)
500 struct fw_name_devm *fwn = res;
502 if (fwn->magic == (unsigned long)&fw_cache)
503 pr_debug("%s: fw_name-%s devm-%p released\n",
504 __func__, fwn->name, res);
505 kfree_const(fwn->name);
508 static int fw_devm_match(struct device *dev, void *res,
511 struct fw_name_devm *fwn = res;
513 return (fwn->magic == (unsigned long)&fw_cache) &&
514 !strcmp(fwn->name, match_data);
517 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
520 struct fw_name_devm *fwn;
522 fwn = devres_find(dev, fw_name_devm_release,
523 fw_devm_match, (void *)name);
527 /* add firmware name into devres list */
528 static int fw_add_devm_name(struct device *dev, const char *name)
530 struct fw_name_devm *fwn;
532 fwn = fw_find_devm_name(dev, name);
536 fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
540 fwn->name = kstrdup_const(name, GFP_KERNEL);
546 fwn->magic = (unsigned long)&fw_cache;
547 devres_add(dev, fwn);
552 static int fw_add_devm_name(struct device *dev, const char *name)
558 static int assign_firmware_buf(struct firmware *fw, struct device *device,
559 unsigned int opt_flags)
561 struct firmware_buf *buf = fw->priv;
563 mutex_lock(&fw_lock);
564 if (!buf->size || fw_state_is_aborted(&buf->fw_st)) {
565 mutex_unlock(&fw_lock);
570 * add firmware name into devres list so that we can auto cache
571 * and uncache firmware for device.
573 * device may has been deleted already, but the problem
574 * should be fixed in devres or driver core.
576 /* don't cache firmware handled without uevent */
577 if (device && (opt_flags & FW_OPT_UEVENT) &&
578 !(opt_flags & FW_OPT_NOCACHE))
579 fw_add_devm_name(device, buf->fw_id);
582 * After caching firmware image is started, let it piggyback
583 * on request firmware.
585 if (!(opt_flags & FW_OPT_NOCACHE) &&
586 buf->fwc->state == FW_LOADER_START_CACHE) {
587 if (fw_cache_piggyback_on_request(buf->fw_id))
591 /* pass the pages buffer to driver at the last minute */
592 fw_set_page_data(buf, fw);
593 mutex_unlock(&fw_lock);
598 * user-mode helper code
600 #ifdef CONFIG_FW_LOADER_USER_HELPER
601 struct firmware_priv {
604 struct firmware_buf *buf;
608 static struct firmware_priv *to_firmware_priv(struct device *dev)
610 return container_of(dev, struct firmware_priv, dev);
613 static void __fw_load_abort(struct firmware_buf *buf)
616 * There is a small window in which user can write to 'loading'
617 * between loading done and disappearance of 'loading'
619 if (fw_state_is_done(&buf->fw_st))
622 list_del_init(&buf->pending_list);
623 fw_state_aborted(&buf->fw_st);
626 static void fw_load_abort(struct firmware_priv *fw_priv)
628 struct firmware_buf *buf = fw_priv->buf;
630 __fw_load_abort(buf);
633 static LIST_HEAD(pending_fw_head);
635 static void kill_pending_fw_fallback_reqs(bool only_kill_custom)
637 struct firmware_buf *buf;
638 struct firmware_buf *next;
640 mutex_lock(&fw_lock);
641 list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
642 if (!buf->need_uevent || !only_kill_custom)
643 __fw_load_abort(buf);
645 mutex_unlock(&fw_lock);
648 static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
651 return sprintf(buf, "%d\n", loading_timeout);
655 * firmware_timeout_store - set number of seconds to wait for firmware
656 * @class: device class pointer
657 * @attr: device attribute pointer
658 * @buf: buffer to scan for timeout value
659 * @count: number of bytes in @buf
661 * Sets the number of seconds to wait for the firmware. Once
662 * this expires an error will be returned to the driver and no
663 * firmware will be provided.
665 * Note: zero means 'wait forever'.
667 static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
668 const char *buf, size_t count)
670 loading_timeout = simple_strtol(buf, NULL, 10);
671 if (loading_timeout < 0)
676 static CLASS_ATTR_RW(timeout);
678 static struct attribute *firmware_class_attrs[] = {
679 &class_attr_timeout.attr,
682 ATTRIBUTE_GROUPS(firmware_class);
684 static void fw_dev_release(struct device *dev)
686 struct firmware_priv *fw_priv = to_firmware_priv(dev);
691 static int do_firmware_uevent(struct firmware_priv *fw_priv, struct kobj_uevent_env *env)
693 if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
695 if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
697 if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
703 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
705 struct firmware_priv *fw_priv = to_firmware_priv(dev);
708 mutex_lock(&fw_lock);
710 err = do_firmware_uevent(fw_priv, env);
711 mutex_unlock(&fw_lock);
715 static struct class firmware_class = {
717 .class_groups = firmware_class_groups,
718 .dev_uevent = firmware_uevent,
719 .dev_release = fw_dev_release,
722 static ssize_t firmware_loading_show(struct device *dev,
723 struct device_attribute *attr, char *buf)
725 struct firmware_priv *fw_priv = to_firmware_priv(dev);
728 mutex_lock(&fw_lock);
730 loading = fw_state_is_loading(&fw_priv->buf->fw_st);
731 mutex_unlock(&fw_lock);
733 return sprintf(buf, "%d\n", loading);
736 /* Some architectures don't have PAGE_KERNEL_RO */
737 #ifndef PAGE_KERNEL_RO
738 #define PAGE_KERNEL_RO PAGE_KERNEL
741 /* one pages buffer should be mapped/unmapped only once */
742 static int fw_map_pages_buf(struct firmware_buf *buf)
744 if (!buf->is_paged_buf)
748 buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
755 * firmware_loading_store - set value in the 'loading' control file
756 * @dev: device pointer
757 * @attr: device attribute pointer
758 * @buf: buffer to scan for loading control value
759 * @count: number of bytes in @buf
761 * The relevant values are:
763 * 1: Start a load, discarding any previous partial load.
764 * 0: Conclude the load and hand the data to the driver code.
765 * -1: Conclude the load with an error and discard any written data.
767 static ssize_t firmware_loading_store(struct device *dev,
768 struct device_attribute *attr,
769 const char *buf, size_t count)
771 struct firmware_priv *fw_priv = to_firmware_priv(dev);
772 struct firmware_buf *fw_buf;
773 ssize_t written = count;
774 int loading = simple_strtol(buf, NULL, 10);
777 mutex_lock(&fw_lock);
778 fw_buf = fw_priv->buf;
779 if (fw_state_is_aborted(&fw_buf->fw_st))
784 /* discarding any previous partial load */
785 if (!fw_state_is_done(&fw_buf->fw_st)) {
786 for (i = 0; i < fw_buf->nr_pages; i++)
787 __free_page(fw_buf->pages[i]);
788 vfree(fw_buf->pages);
789 fw_buf->pages = NULL;
790 fw_buf->page_array_size = 0;
791 fw_buf->nr_pages = 0;
792 fw_state_start(&fw_buf->fw_st);
796 if (fw_state_is_loading(&fw_buf->fw_st)) {
800 * Several loading requests may be pending on
801 * one same firmware buf, so let all requests
802 * see the mapped 'buf->data' once the loading
805 rc = fw_map_pages_buf(fw_buf);
807 dev_err(dev, "%s: map pages failed\n",
810 rc = security_kernel_post_read_file(NULL,
811 fw_buf->data, fw_buf->size,
815 * Same logic as fw_load_abort, only the DONE bit
816 * is ignored and we set ABORT only on failure.
818 list_del_init(&fw_buf->pending_list);
820 fw_state_aborted(&fw_buf->fw_st);
823 fw_state_done(&fw_buf->fw_st);
829 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
832 fw_load_abort(fw_priv);
836 mutex_unlock(&fw_lock);
840 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
842 static void firmware_rw_buf(struct firmware_buf *buf, char *buffer,
843 loff_t offset, size_t count, bool read)
846 memcpy(buffer, buf->data + offset, count);
848 memcpy(buf->data + offset, buffer, count);
851 static void firmware_rw(struct firmware_buf *buf, char *buffer,
852 loff_t offset, size_t count, bool read)
856 int page_nr = offset >> PAGE_SHIFT;
857 int page_ofs = offset & (PAGE_SIZE-1);
858 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
860 page_data = kmap(buf->pages[page_nr]);
863 memcpy(buffer, page_data + page_ofs, page_cnt);
865 memcpy(page_data + page_ofs, buffer, page_cnt);
867 kunmap(buf->pages[page_nr]);
874 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
875 struct bin_attribute *bin_attr,
876 char *buffer, loff_t offset, size_t count)
878 struct device *dev = kobj_to_dev(kobj);
879 struct firmware_priv *fw_priv = to_firmware_priv(dev);
880 struct firmware_buf *buf;
883 mutex_lock(&fw_lock);
885 if (!buf || fw_state_is_done(&buf->fw_st)) {
889 if (offset > buf->size) {
893 if (count > buf->size - offset)
894 count = buf->size - offset;
899 firmware_rw_buf(buf, buffer, offset, count, true);
901 firmware_rw(buf, buffer, offset, count, true);
904 mutex_unlock(&fw_lock);
908 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
910 struct firmware_buf *buf = fw_priv->buf;
911 int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT;
913 /* If the array of pages is too small, grow it... */
914 if (buf->page_array_size < pages_needed) {
915 int new_array_size = max(pages_needed,
916 buf->page_array_size * 2);
917 struct page **new_pages;
919 new_pages = vmalloc(new_array_size * sizeof(void *));
921 fw_load_abort(fw_priv);
924 memcpy(new_pages, buf->pages,
925 buf->page_array_size * sizeof(void *));
926 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
927 (new_array_size - buf->page_array_size));
929 buf->pages = new_pages;
930 buf->page_array_size = new_array_size;
933 while (buf->nr_pages < pages_needed) {
934 buf->pages[buf->nr_pages] =
935 alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
937 if (!buf->pages[buf->nr_pages]) {
938 fw_load_abort(fw_priv);
947 * firmware_data_write - write method for firmware
948 * @filp: open sysfs file
949 * @kobj: kobject for the device
950 * @bin_attr: bin_attr structure
951 * @buffer: buffer being written
952 * @offset: buffer offset for write in total data store area
953 * @count: buffer size
955 * Data written to the 'data' attribute will be later handed to
956 * the driver as a firmware image.
958 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
959 struct bin_attribute *bin_attr,
960 char *buffer, loff_t offset, size_t count)
962 struct device *dev = kobj_to_dev(kobj);
963 struct firmware_priv *fw_priv = to_firmware_priv(dev);
964 struct firmware_buf *buf;
967 if (!capable(CAP_SYS_RAWIO))
970 mutex_lock(&fw_lock);
972 if (!buf || fw_state_is_done(&buf->fw_st)) {
978 if (offset + count > buf->allocated_size) {
982 firmware_rw_buf(buf, buffer, offset, count, false);
985 retval = fw_realloc_buffer(fw_priv, offset + count);
990 firmware_rw(buf, buffer, offset, count, false);
993 buf->size = max_t(size_t, offset + count, buf->size);
995 mutex_unlock(&fw_lock);
999 static struct bin_attribute firmware_attr_data = {
1000 .attr = { .name = "data", .mode = 0644 },
1002 .read = firmware_data_read,
1003 .write = firmware_data_write,
1006 static struct attribute *fw_dev_attrs[] = {
1007 &dev_attr_loading.attr,
1011 static struct bin_attribute *fw_dev_bin_attrs[] = {
1012 &firmware_attr_data,
1016 static const struct attribute_group fw_dev_attr_group = {
1017 .attrs = fw_dev_attrs,
1018 .bin_attrs = fw_dev_bin_attrs,
1021 static const struct attribute_group *fw_dev_attr_groups[] = {
1026 static struct firmware_priv *
1027 fw_create_instance(struct firmware *firmware, const char *fw_name,
1028 struct device *device, unsigned int opt_flags)
1030 struct firmware_priv *fw_priv;
1031 struct device *f_dev;
1033 fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
1035 fw_priv = ERR_PTR(-ENOMEM);
1039 fw_priv->nowait = !!(opt_flags & FW_OPT_NOWAIT);
1040 fw_priv->fw = firmware;
1041 f_dev = &fw_priv->dev;
1043 device_initialize(f_dev);
1044 dev_set_name(f_dev, "%s", fw_name);
1045 f_dev->parent = device;
1046 f_dev->class = &firmware_class;
1047 f_dev->groups = fw_dev_attr_groups;
1052 /* load a firmware via user helper */
1053 static int _request_firmware_load(struct firmware_priv *fw_priv,
1054 unsigned int opt_flags, long timeout)
1057 struct device *f_dev = &fw_priv->dev;
1058 struct firmware_buf *buf = fw_priv->buf;
1060 /* fall back on userspace loading */
1062 buf->is_paged_buf = true;
1064 dev_set_uevent_suppress(f_dev, true);
1066 retval = device_add(f_dev);
1068 dev_err(f_dev, "%s: device_register failed\n", __func__);
1072 mutex_lock(&fw_lock);
1073 list_add(&buf->pending_list, &pending_fw_head);
1074 mutex_unlock(&fw_lock);
1076 if (opt_flags & FW_OPT_UEVENT) {
1077 buf->need_uevent = true;
1078 dev_set_uevent_suppress(f_dev, false);
1079 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
1080 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
1082 timeout = MAX_JIFFY_OFFSET;
1085 retval = fw_state_wait_timeout(&buf->fw_st, timeout);
1087 mutex_lock(&fw_lock);
1088 fw_load_abort(fw_priv);
1089 mutex_unlock(&fw_lock);
1092 if (fw_state_is_aborted(&buf->fw_st))
1094 else if (buf->is_paged_buf && !buf->data)
1103 static int fw_load_from_user_helper(struct firmware *firmware,
1104 const char *name, struct device *device,
1105 unsigned int opt_flags, long timeout)
1107 struct firmware_priv *fw_priv;
1109 fw_priv = fw_create_instance(firmware, name, device, opt_flags);
1110 if (IS_ERR(fw_priv))
1111 return PTR_ERR(fw_priv);
1113 fw_priv->buf = firmware->priv;
1114 return _request_firmware_load(fw_priv, opt_flags, timeout);
1117 #else /* CONFIG_FW_LOADER_USER_HELPER */
1119 fw_load_from_user_helper(struct firmware *firmware, const char *name,
1120 struct device *device, unsigned int opt_flags,
1126 static inline void kill_pending_fw_fallback_reqs(bool only_kill_custom) { }
1128 #endif /* CONFIG_FW_LOADER_USER_HELPER */
1130 /* prepare firmware and firmware_buf structs;
1131 * return 0 if a firmware is already assigned, 1 if need to load one,
1132 * or a negative error code
1135 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
1136 struct device *device, void *dbuf, size_t size)
1138 struct firmware *firmware;
1139 struct firmware_buf *buf;
1142 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
1144 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
1149 if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
1150 dev_dbg(device, "using built-in %s\n", name);
1151 return 0; /* assigned */
1154 ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf, dbuf, size);
1157 * bind with 'buf' now to avoid warning in failure path
1158 * of requesting firmware.
1160 firmware->priv = buf;
1163 ret = fw_state_wait(&buf->fw_st);
1165 fw_set_page_data(buf, firmware);
1166 return 0; /* assigned */
1172 return 1; /* need to load */
1175 /* called from request_firmware() and request_firmware_work_func() */
1177 _request_firmware(const struct firmware **firmware_p, const char *name,
1178 struct device *device, void *buf, size_t size,
1179 unsigned int opt_flags)
1181 struct firmware *fw = NULL;
1188 if (!name || name[0] == '\0') {
1193 ret = _request_firmware_prepare(&fw, name, device, buf, size);
1194 if (ret <= 0) /* error or already assigned */
1197 if (!firmware_enabled()) {
1198 WARN(1, "firmware request while host is not available\n");
1204 timeout = firmware_loading_timeout();
1205 if (opt_flags & FW_OPT_NOWAIT) {
1206 timeout = usermodehelper_read_lock_wait(timeout);
1208 dev_dbg(device, "firmware: %s loading timed out\n",
1214 ret = usermodehelper_read_trylock();
1216 dev_err(device, "firmware: %s will not be loaded\n",
1222 ret = fw_get_filesystem_firmware(device, fw->priv);
1224 if (!(opt_flags & FW_OPT_NO_WARN))
1226 "Direct firmware load for %s failed with error %d\n",
1228 if (opt_flags & FW_OPT_USERHELPER) {
1229 dev_warn(device, "Falling back to user helper\n");
1230 ret = fw_load_from_user_helper(fw, name, device,
1231 opt_flags, timeout);
1236 ret = assign_firmware_buf(fw, device, opt_flags);
1238 usermodehelper_read_unlock();
1242 release_firmware(fw);
1251 * request_firmware: - send firmware request and wait for it
1252 * @firmware_p: pointer to firmware image
1253 * @name: name of firmware file
1254 * @device: device for which firmware is being loaded
1256 * @firmware_p will be used to return a firmware image by the name
1257 * of @name for device @device.
1259 * Should be called from user context where sleeping is allowed.
1261 * @name will be used as $FIRMWARE in the uevent environment and
1262 * should be distinctive enough not to be confused with any other
1263 * firmware image for this or any other device.
1265 * Caller must hold the reference count of @device.
1267 * The function can be called safely inside device's suspend and
1271 request_firmware(const struct firmware **firmware_p, const char *name,
1272 struct device *device)
1276 /* Need to pin this module until return */
1277 __module_get(THIS_MODULE);
1278 ret = _request_firmware(firmware_p, name, device, NULL, 0,
1279 FW_OPT_UEVENT | FW_OPT_FALLBACK);
1280 module_put(THIS_MODULE);
1283 EXPORT_SYMBOL(request_firmware);
1286 * request_firmware_direct: - load firmware directly without usermode helper
1287 * @firmware_p: pointer to firmware image
1288 * @name: name of firmware file
1289 * @device: device for which firmware is being loaded
1291 * This function works pretty much like request_firmware(), but this doesn't
1292 * fall back to usermode helper even if the firmware couldn't be loaded
1293 * directly from fs. Hence it's useful for loading optional firmwares, which
1294 * aren't always present, without extra long timeouts of udev.
1296 int request_firmware_direct(const struct firmware **firmware_p,
1297 const char *name, struct device *device)
1301 __module_get(THIS_MODULE);
1302 ret = _request_firmware(firmware_p, name, device, NULL, 0,
1303 FW_OPT_UEVENT | FW_OPT_NO_WARN);
1304 module_put(THIS_MODULE);
1307 EXPORT_SYMBOL_GPL(request_firmware_direct);
1310 * request_firmware_into_buf - load firmware into a previously allocated buffer
1311 * @firmware_p: pointer to firmware image
1312 * @name: name of firmware file
1313 * @device: device for which firmware is being loaded and DMA region allocated
1314 * @buf: address of buffer to load firmware into
1315 * @size: size of buffer
1317 * This function works pretty much like request_firmware(), but it doesn't
1318 * allocate a buffer to hold the firmware data. Instead, the firmware
1319 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
1320 * data member is pointed at @buf.
1322 * This function doesn't cache firmware either.
1325 request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
1326 struct device *device, void *buf, size_t size)
1330 __module_get(THIS_MODULE);
1331 ret = _request_firmware(firmware_p, name, device, buf, size,
1332 FW_OPT_UEVENT | FW_OPT_FALLBACK |
1334 module_put(THIS_MODULE);
1337 EXPORT_SYMBOL(request_firmware_into_buf);
1340 * release_firmware: - release the resource associated with a firmware image
1341 * @fw: firmware resource to release
1343 void release_firmware(const struct firmware *fw)
1346 if (!fw_is_builtin_firmware(fw))
1347 firmware_free_data(fw);
1351 EXPORT_SYMBOL(release_firmware);
1354 struct firmware_work {
1355 struct work_struct work;
1356 struct module *module;
1358 struct device *device;
1360 void (*cont)(const struct firmware *fw, void *context);
1361 unsigned int opt_flags;
1364 static void request_firmware_work_func(struct work_struct *work)
1366 struct firmware_work *fw_work;
1367 const struct firmware *fw;
1369 fw_work = container_of(work, struct firmware_work, work);
1371 _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0,
1372 fw_work->opt_flags);
1373 fw_work->cont(fw, fw_work->context);
1374 put_device(fw_work->device); /* taken in request_firmware_nowait() */
1376 module_put(fw_work->module);
1377 kfree_const(fw_work->name);
1382 * request_firmware_nowait - asynchronous version of request_firmware
1383 * @module: module requesting the firmware
1384 * @uevent: sends uevent to copy the firmware image if this flag
1385 * is non-zero else the firmware copy must be done manually.
1386 * @name: name of firmware file
1387 * @device: device for which firmware is being loaded
1388 * @gfp: allocation flags
1389 * @context: will be passed over to @cont, and
1390 * @fw may be %NULL if firmware request fails.
1391 * @cont: function will be called asynchronously when the firmware
1394 * Caller must hold the reference count of @device.
1396 * Asynchronous variant of request_firmware() for user contexts:
1397 * - sleep for as small periods as possible since it may
1398 * increase kernel boot time of built-in device drivers
1399 * requesting firmware in their ->probe() methods, if
1400 * @gfp is GFP_KERNEL.
1402 * - can't sleep at all if @gfp is GFP_ATOMIC.
1405 request_firmware_nowait(
1406 struct module *module, bool uevent,
1407 const char *name, struct device *device, gfp_t gfp, void *context,
1408 void (*cont)(const struct firmware *fw, void *context))
1410 struct firmware_work *fw_work;
1412 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1416 fw_work->module = module;
1417 fw_work->name = kstrdup_const(name, gfp);
1418 if (!fw_work->name) {
1422 fw_work->device = device;
1423 fw_work->context = context;
1424 fw_work->cont = cont;
1425 fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
1426 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1428 if (!try_module_get(module)) {
1429 kfree_const(fw_work->name);
1434 get_device(fw_work->device);
1435 INIT_WORK(&fw_work->work, request_firmware_work_func);
1436 schedule_work(&fw_work->work);
1439 EXPORT_SYMBOL(request_firmware_nowait);
1441 #ifdef CONFIG_PM_SLEEP
1442 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1445 * cache_firmware - cache one firmware image in kernel memory space
1446 * @fw_name: the firmware image name
1448 * Cache firmware in kernel memory so that drivers can use it when
1449 * system isn't ready for them to request firmware image from userspace.
1450 * Once it returns successfully, driver can use request_firmware or its
1451 * nowait version to get the cached firmware without any interacting
1454 * Return 0 if the firmware image has been cached successfully
1455 * Return !0 otherwise
1458 static int cache_firmware(const char *fw_name)
1461 const struct firmware *fw;
1463 pr_debug("%s: %s\n", __func__, fw_name);
1465 ret = request_firmware(&fw, fw_name, NULL);
1469 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1474 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1476 struct firmware_buf *tmp;
1477 struct firmware_cache *fwc = &fw_cache;
1479 spin_lock(&fwc->lock);
1480 tmp = __fw_lookup_buf(fw_name);
1481 spin_unlock(&fwc->lock);
1487 * uncache_firmware - remove one cached firmware image
1488 * @fw_name: the firmware image name
1490 * Uncache one firmware image which has been cached successfully
1493 * Return 0 if the firmware cache has been removed successfully
1494 * Return !0 otherwise
1497 static int uncache_firmware(const char *fw_name)
1499 struct firmware_buf *buf;
1502 pr_debug("%s: %s\n", __func__, fw_name);
1504 if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
1507 buf = fw_lookup_buf(fw_name);
1516 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1518 struct fw_cache_entry *fce;
1520 fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1524 fce->name = kstrdup_const(name, GFP_ATOMIC);
1534 static int __fw_entry_found(const char *name)
1536 struct firmware_cache *fwc = &fw_cache;
1537 struct fw_cache_entry *fce;
1539 list_for_each_entry(fce, &fwc->fw_names, list) {
1540 if (!strcmp(fce->name, name))
1546 static int fw_cache_piggyback_on_request(const char *name)
1548 struct firmware_cache *fwc = &fw_cache;
1549 struct fw_cache_entry *fce;
1552 spin_lock(&fwc->name_lock);
1553 if (__fw_entry_found(name))
1556 fce = alloc_fw_cache_entry(name);
1559 list_add(&fce->list, &fwc->fw_names);
1560 pr_debug("%s: fw: %s\n", __func__, name);
1563 spin_unlock(&fwc->name_lock);
1567 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1569 kfree_const(fce->name);
1573 static void __async_dev_cache_fw_image(void *fw_entry,
1574 async_cookie_t cookie)
1576 struct fw_cache_entry *fce = fw_entry;
1577 struct firmware_cache *fwc = &fw_cache;
1580 ret = cache_firmware(fce->name);
1582 spin_lock(&fwc->name_lock);
1583 list_del(&fce->list);
1584 spin_unlock(&fwc->name_lock);
1586 free_fw_cache_entry(fce);
1590 /* called with dev->devres_lock held */
1591 static void dev_create_fw_entry(struct device *dev, void *res,
1594 struct fw_name_devm *fwn = res;
1595 const char *fw_name = fwn->name;
1596 struct list_head *head = data;
1597 struct fw_cache_entry *fce;
1599 fce = alloc_fw_cache_entry(fw_name);
1601 list_add(&fce->list, head);
1604 static int devm_name_match(struct device *dev, void *res,
1607 struct fw_name_devm *fwn = res;
1608 return (fwn->magic == (unsigned long)match_data);
1611 static void dev_cache_fw_image(struct device *dev, void *data)
1614 struct fw_cache_entry *fce;
1615 struct fw_cache_entry *fce_next;
1616 struct firmware_cache *fwc = &fw_cache;
1618 devres_for_each_res(dev, fw_name_devm_release,
1619 devm_name_match, &fw_cache,
1620 dev_create_fw_entry, &todo);
1622 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1623 list_del(&fce->list);
1625 spin_lock(&fwc->name_lock);
1626 /* only one cache entry for one firmware */
1627 if (!__fw_entry_found(fce->name)) {
1628 list_add(&fce->list, &fwc->fw_names);
1630 free_fw_cache_entry(fce);
1633 spin_unlock(&fwc->name_lock);
1636 async_schedule_domain(__async_dev_cache_fw_image,
1642 static void __device_uncache_fw_images(void)
1644 struct firmware_cache *fwc = &fw_cache;
1645 struct fw_cache_entry *fce;
1647 spin_lock(&fwc->name_lock);
1648 while (!list_empty(&fwc->fw_names)) {
1649 fce = list_entry(fwc->fw_names.next,
1650 struct fw_cache_entry, list);
1651 list_del(&fce->list);
1652 spin_unlock(&fwc->name_lock);
1654 uncache_firmware(fce->name);
1655 free_fw_cache_entry(fce);
1657 spin_lock(&fwc->name_lock);
1659 spin_unlock(&fwc->name_lock);
1663 * device_cache_fw_images - cache devices' firmware
1665 * If one device called request_firmware or its nowait version
1666 * successfully before, the firmware names are recored into the
1667 * device's devres link list, so device_cache_fw_images can call
1668 * cache_firmware() to cache these firmwares for the device,
1669 * then the device driver can load its firmwares easily at
1670 * time when system is not ready to complete loading firmware.
1672 static void device_cache_fw_images(void)
1674 struct firmware_cache *fwc = &fw_cache;
1678 pr_debug("%s\n", __func__);
1680 /* cancel uncache work */
1681 cancel_delayed_work_sync(&fwc->work);
1684 * use small loading timeout for caching devices' firmware
1685 * because all these firmware images have been loaded
1686 * successfully at lease once, also system is ready for
1687 * completing firmware loading now. The maximum size of
1688 * firmware in current distributions is about 2M bytes,
1689 * so 10 secs should be enough.
1691 old_timeout = loading_timeout;
1692 loading_timeout = 10;
1694 mutex_lock(&fw_lock);
1695 fwc->state = FW_LOADER_START_CACHE;
1696 dpm_for_each_dev(NULL, dev_cache_fw_image);
1697 mutex_unlock(&fw_lock);
1699 /* wait for completion of caching firmware for all devices */
1700 async_synchronize_full_domain(&fw_cache_domain);
1702 loading_timeout = old_timeout;
1706 * device_uncache_fw_images - uncache devices' firmware
1708 * uncache all firmwares which have been cached successfully
1709 * by device_uncache_fw_images earlier
1711 static void device_uncache_fw_images(void)
1713 pr_debug("%s\n", __func__);
1714 __device_uncache_fw_images();
1717 static void device_uncache_fw_images_work(struct work_struct *work)
1719 device_uncache_fw_images();
1723 * device_uncache_fw_images_delay - uncache devices firmwares
1724 * @delay: number of milliseconds to delay uncache device firmwares
1726 * uncache all devices's firmwares which has been cached successfully
1727 * by device_cache_fw_images after @delay milliseconds.
1729 static void device_uncache_fw_images_delay(unsigned long delay)
1731 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1732 msecs_to_jiffies(delay));
1736 * fw_pm_notify - notifier for suspend/resume
1737 * @notify_block: unused
1738 * @mode: mode we are switching to
1741 * Used to modify the firmware_class state as we move in between states.
1742 * The firmware_class implements a firmware cache to enable device driver
1743 * to fetch firmware upon resume before the root filesystem is ready. We
1744 * disable API calls which do not use the built-in firmware or the firmware
1745 * cache when we know these calls will not work.
1747 * The inner logic behind all this is a bit complex so it is worth summarizing
1748 * the kernel's own suspend/resume process with context and focus on how this
1749 * can impact the firmware API.
1751 * First a review on how we go to suspend::
1753 * pm_suspend() --> enter_state() -->
1755 * suspend_prepare() -->
1756 * __pm_notifier_call_chain(PM_SUSPEND_PREPARE, ...);
1757 * suspend_freeze_processes() -->
1758 * freeze_processes() -->
1759 * __usermodehelper_set_disable_depth(UMH_DISABLED);
1760 * freeze all tasks ...
1761 * freeze_kernel_threads()
1762 * suspend_devices_and_enter() -->
1763 * dpm_suspend_start() -->
1766 * suspend_enter() -->
1767 * platform_suspend_prepare()
1768 * dpm_suspend_late()
1772 * When we resume we bail out of a loop from suspend_devices_and_enter() and
1773 * unwind back out to the caller enter_state() where we were before as follows::
1776 * suspend_devices_and_enter() --> (bail from loop)
1777 * dpm_resume_end() -->
1780 * suspend_finish() -->
1781 * suspend_thaw_processes() -->
1782 * thaw_processes() -->
1783 * __usermodehelper_set_disable_depth(UMH_FREEZING);
1784 * thaw_workqueues();
1785 * thaw all processes ...
1786 * usermodehelper_enable();
1787 * pm_notifier_call_chain(PM_POST_SUSPEND);
1789 * fw_pm_notify() works through pm_notifier_call_chain().
1791 static int fw_pm_notify(struct notifier_block *notify_block,
1792 unsigned long mode, void *unused)
1795 case PM_HIBERNATION_PREPARE:
1796 case PM_SUSPEND_PREPARE:
1797 case PM_RESTORE_PREPARE:
1799 * kill pending fallback requests with a custom fallback
1800 * to avoid stalling suspend.
1802 kill_pending_fw_fallback_reqs(true);
1803 device_cache_fw_images();
1807 case PM_POST_SUSPEND:
1808 case PM_POST_HIBERNATION:
1809 case PM_POST_RESTORE:
1811 * In case that system sleep failed and syscore_suspend is
1814 mutex_lock(&fw_lock);
1815 fw_cache.state = FW_LOADER_NO_CACHE;
1816 mutex_unlock(&fw_lock);
1819 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1826 /* stop caching firmware once syscore_suspend is reached */
1827 static int fw_suspend(void)
1829 fw_cache.state = FW_LOADER_NO_CACHE;
1833 static struct syscore_ops fw_syscore_ops = {
1834 .suspend = fw_suspend,
1837 static int fw_cache_piggyback_on_request(const char *name)
1843 static void __init fw_cache_init(void)
1845 spin_lock_init(&fw_cache.lock);
1846 INIT_LIST_HEAD(&fw_cache.head);
1847 fw_cache.state = FW_LOADER_NO_CACHE;
1849 #ifdef CONFIG_PM_SLEEP
1850 spin_lock_init(&fw_cache.name_lock);
1851 INIT_LIST_HEAD(&fw_cache.fw_names);
1853 INIT_DELAYED_WORK(&fw_cache.work,
1854 device_uncache_fw_images_work);
1856 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1857 register_pm_notifier(&fw_cache.pm_notify);
1859 register_syscore_ops(&fw_syscore_ops);
1863 static int fw_shutdown_notify(struct notifier_block *unused1,
1864 unsigned long unused2, void *unused3)
1868 * Kill all pending fallback requests to avoid both stalling shutdown,
1869 * and avoid a deadlock with the usermode_lock.
1871 kill_pending_fw_fallback_reqs(false);
1876 static struct notifier_block fw_shutdown_nb = {
1877 .notifier_call = fw_shutdown_notify,
1880 static int __init firmware_class_init(void)
1884 register_reboot_notifier(&fw_shutdown_nb);
1885 #ifdef CONFIG_FW_LOADER_USER_HELPER
1886 return class_register(&firmware_class);
1892 static void __exit firmware_class_exit(void)
1895 #ifdef CONFIG_PM_SLEEP
1896 unregister_syscore_ops(&fw_syscore_ops);
1897 unregister_pm_notifier(&fw_cache.pm_notify);
1899 unregister_reboot_notifier(&fw_shutdown_nb);
1900 #ifdef CONFIG_FW_LOADER_USER_HELPER
1901 class_unregister(&firmware_class);
1905 fs_initcall(firmware_class_init);
1906 module_exit(firmware_class_exit);