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#include <linux/reboot.h>
31#include <linux/security.h>
32
33#include <generated/utsrelease.h>
34
35#include "base.h"
36
37MODULE_AUTHOR("Manuel Estrada Sainz");
38MODULE_DESCRIPTION("Multi purpose firmware loading support");
39MODULE_LICENSE("GPL");
40
41/* Builtin firmware support */
42
43#ifdef CONFIG_FW_LOADER
44
45extern struct builtin_fw __start_builtin_fw[];
46extern struct builtin_fw __end_builtin_fw[];
47
48static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
49{
50	struct builtin_fw *b_fw;
51
52	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
53		if (strcmp(name, b_fw->name) == 0) {
54			fw->size = b_fw->size;
55			fw->data = b_fw->data;
56			return true;
57		}
58	}
59
60	return false;
61}
62
63static bool fw_is_builtin_firmware(const struct firmware *fw)
64{
65	struct builtin_fw *b_fw;
66
67	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
68		if (fw->data == b_fw->data)
69			return true;
70
71	return false;
72}
73
74#else /* Module case - no builtin firmware support */
75
76static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
77{
78	return false;
79}
80
81static inline bool fw_is_builtin_firmware(const struct firmware *fw)
82{
83	return false;
84}
85#endif
86
87enum {
88	FW_STATUS_LOADING,
89	FW_STATUS_DONE,
90	FW_STATUS_ABORT,
91};
92
93static int loading_timeout = 60;	/* In seconds */
94
95static inline long firmware_loading_timeout(void)
96{
97	return loading_timeout > 0 ? loading_timeout * HZ : MAX_JIFFY_OFFSET;
98}
99
100/* firmware behavior options */
101#define FW_OPT_UEVENT	(1U << 0)
102#define FW_OPT_NOWAIT	(1U << 1)
103#ifdef CONFIG_FW_LOADER_USER_HELPER
104#define FW_OPT_USERHELPER	(1U << 2)
105#else
106#define FW_OPT_USERHELPER	0
107#endif
108#ifdef CONFIG_FW_LOADER_USER_HELPER_FALLBACK
109#define FW_OPT_FALLBACK		FW_OPT_USERHELPER
110#else
111#define FW_OPT_FALLBACK		0
112#endif
113#define FW_OPT_NO_WARN	(1U << 3)
114
115struct firmware_cache {
116	/* firmware_buf instance will be added into the below list */
117	spinlock_t lock;
118	struct list_head head;
119	int state;
120
121#ifdef CONFIG_PM_SLEEP
122	/*
123	 * Names of firmware images which have been cached successfully
124	 * will be added into the below list so that device uncache
125	 * helper can trace which firmware images have been cached
126	 * before.
127	 */
128	spinlock_t name_lock;
129	struct list_head fw_names;
130
131	struct delayed_work work;
132
133	struct notifier_block   pm_notify;
134#endif
135};
136
137struct firmware_buf {
138	struct kref ref;
139	struct list_head list;
140	struct completion completion;
141	struct firmware_cache *fwc;
142	unsigned long status;
143	void *data;
144	size_t size;
145#ifdef CONFIG_FW_LOADER_USER_HELPER
146	bool is_paged_buf;
147	bool need_uevent;
148	struct page **pages;
149	int nr_pages;
150	int page_array_size;
151	struct list_head pending_list;
152#endif
153	char fw_id[];
154};
155
156struct fw_cache_entry {
157	struct list_head list;
158	char name[];
159};
160
161struct fw_name_devm {
162	unsigned long magic;
163	char name[];
164};
165
166#define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
167
168#define	FW_LOADER_NO_CACHE	0
169#define	FW_LOADER_START_CACHE	1
170
171static int fw_cache_piggyback_on_request(const char *name);
172
173/* fw_lock could be moved to 'struct firmware_priv' but since it is just
174 * guarding for corner cases a global lock should be OK */
175static DEFINE_MUTEX(fw_lock);
176
177static struct firmware_cache fw_cache;
178
179static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
180					      struct firmware_cache *fwc)
181{
182	struct firmware_buf *buf;
183
184	buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1, GFP_ATOMIC);
185
186	if (!buf)
187		return buf;
188
189	kref_init(&buf->ref);
190	strcpy(buf->fw_id, fw_name);
191	buf->fwc = fwc;
192	init_completion(&buf->completion);
193#ifdef CONFIG_FW_LOADER_USER_HELPER
194	INIT_LIST_HEAD(&buf->pending_list);
195#endif
196
197	pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
198
199	return buf;
200}
201
202static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
203{
204	struct firmware_buf *tmp;
205	struct firmware_cache *fwc = &fw_cache;
206
207	list_for_each_entry(tmp, &fwc->head, list)
208		if (!strcmp(tmp->fw_id, fw_name))
209			return tmp;
210	return NULL;
211}
212
213static int fw_lookup_and_allocate_buf(const char *fw_name,
214				      struct firmware_cache *fwc,
215				      struct firmware_buf **buf)
216{
217	struct firmware_buf *tmp;
218
219	spin_lock(&fwc->lock);
220	tmp = __fw_lookup_buf(fw_name);
221	if (tmp) {
222		kref_get(&tmp->ref);
223		spin_unlock(&fwc->lock);
224		*buf = tmp;
225		return 1;
226	}
227	tmp = __allocate_fw_buf(fw_name, fwc);
228	if (tmp)
229		list_add(&tmp->list, &fwc->head);
230	spin_unlock(&fwc->lock);
231
232	*buf = tmp;
233
234	return tmp ? 0 : -ENOMEM;
235}
236
237static void __fw_free_buf(struct kref *ref)
238	__releases(&fwc->lock)
239{
240	struct firmware_buf *buf = to_fwbuf(ref);
241	struct firmware_cache *fwc = buf->fwc;
242
243	pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
244		 __func__, buf->fw_id, buf, buf->data,
245		 (unsigned int)buf->size);
246
247	list_del(&buf->list);
248	spin_unlock(&fwc->lock);
249
250#ifdef CONFIG_FW_LOADER_USER_HELPER
251	if (buf->is_paged_buf) {
252		int i;
253		vunmap(buf->data);
254		for (i = 0; i < buf->nr_pages; i++)
255			__free_page(buf->pages[i]);
256		kfree(buf->pages);
257	} else
258#endif
259		vfree(buf->data);
260	kfree(buf);
261}
262
263static 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 */
272static char fw_path_para[256];
273static 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 */
286module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
287MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
288
289static int fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
290{
291	int size;
292	char *buf;
293	int rc;
294
295	if (!S_ISREG(file_inode(file)->i_mode))
296		return -EINVAL;
297	size = i_size_read(file_inode(file));
298	if (size <= 0)
299		return -EINVAL;
300	buf = vmalloc(size);
301	if (!buf)
302		return -ENOMEM;
303	rc = kernel_read(file, 0, buf, size);
304	if (rc != size) {
305		if (rc > 0)
306			rc = -EIO;
307		goto fail;
308	}
309	rc = security_kernel_fw_from_file(file, buf, size);
310	if (rc)
311		goto fail;
312	fw_buf->data = buf;
313	fw_buf->size = size;
314	return 0;
315fail:
316	vfree(buf);
317	return rc;
318}
319
320static int fw_get_filesystem_firmware(struct device *device,
321				       struct firmware_buf *buf)
322{
323	int i;
324	int rc = -ENOENT;
325	char *path = __getname();
326
327	for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
328		struct file *file;
329
330		/* skip the unset customized path */
331		if (!fw_path[i][0])
332			continue;
333
334		snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
335
336		file = filp_open(path, O_RDONLY, 0);
337		if (IS_ERR(file))
338			continue;
339		rc = fw_read_file_contents(file, buf);
340		fput(file);
341		if (rc)
342			dev_warn(device, "firmware, attempted to load %s, but failed with error %d\n",
343				path, rc);
344		else
345			break;
346	}
347	__putname(path);
348
349	if (!rc) {
350		dev_dbg(device, "firmware: direct-loading firmware %s\n",
351			buf->fw_id);
352		mutex_lock(&fw_lock);
353		set_bit(FW_STATUS_DONE, &buf->status);
354		complete_all(&buf->completion);
355		mutex_unlock(&fw_lock);
356	}
357
358	return rc;
359}
360
361/* firmware holds the ownership of pages */
362static void firmware_free_data(const struct firmware *fw)
363{
364	/* Loaded directly? */
365	if (!fw->priv) {
366		vfree(fw->data);
367		return;
368	}
369	fw_free_buf(fw->priv);
370}
371
372/* store the pages buffer info firmware from buf */
373static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
374{
375	fw->priv = buf;
376#ifdef CONFIG_FW_LOADER_USER_HELPER
377	fw->pages = buf->pages;
378#endif
379	fw->size = buf->size;
380	fw->data = buf->data;
381
382	pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
383		 __func__, buf->fw_id, buf, buf->data,
384		 (unsigned int)buf->size);
385}
386
387#ifdef CONFIG_PM_SLEEP
388static void fw_name_devm_release(struct device *dev, void *res)
389{
390	struct fw_name_devm *fwn = res;
391
392	if (fwn->magic == (unsigned long)&fw_cache)
393		pr_debug("%s: fw_name-%s devm-%p released\n",
394				__func__, fwn->name, res);
395}
396
397static int fw_devm_match(struct device *dev, void *res,
398		void *match_data)
399{
400	struct fw_name_devm *fwn = res;
401
402	return (fwn->magic == (unsigned long)&fw_cache) &&
403		!strcmp(fwn->name, match_data);
404}
405
406static struct fw_name_devm *fw_find_devm_name(struct device *dev,
407		const char *name)
408{
409	struct fw_name_devm *fwn;
410
411	fwn = devres_find(dev, fw_name_devm_release,
412			  fw_devm_match, (void *)name);
413	return fwn;
414}
415
416/* add firmware name into devres list */
417static int fw_add_devm_name(struct device *dev, const char *name)
418{
419	struct fw_name_devm *fwn;
420
421	fwn = fw_find_devm_name(dev, name);
422	if (fwn)
423		return 1;
424
425	fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
426			   strlen(name) + 1, GFP_KERNEL);
427	if (!fwn)
428		return -ENOMEM;
429
430	fwn->magic = (unsigned long)&fw_cache;
431	strcpy(fwn->name, name);
432	devres_add(dev, fwn);
433
434	return 0;
435}
436#else
437static int fw_add_devm_name(struct device *dev, const char *name)
438{
439	return 0;
440}
441#endif
442
443
444/*
445 * user-mode helper code
446 */
447#ifdef CONFIG_FW_LOADER_USER_HELPER
448struct firmware_priv {
449	bool nowait;
450	struct device dev;
451	struct firmware_buf *buf;
452	struct firmware *fw;
453};
454
455static struct firmware_priv *to_firmware_priv(struct device *dev)
456{
457	return container_of(dev, struct firmware_priv, dev);
458}
459
460static void __fw_load_abort(struct firmware_buf *buf)
461{
462	/*
463	 * There is a small window in which user can write to 'loading'
464	 * between loading done and disappearance of 'loading'
465	 */
466	if (test_bit(FW_STATUS_DONE, &buf->status))
467		return;
468
469	list_del_init(&buf->pending_list);
470	set_bit(FW_STATUS_ABORT, &buf->status);
471	complete_all(&buf->completion);
472}
473
474static void fw_load_abort(struct firmware_priv *fw_priv)
475{
476	struct firmware_buf *buf = fw_priv->buf;
477
478	__fw_load_abort(buf);
479
480	/* avoid user action after loading abort */
481	fw_priv->buf = NULL;
482}
483
484#define is_fw_load_aborted(buf)	\
485	test_bit(FW_STATUS_ABORT, &(buf)->status)
486
487static LIST_HEAD(pending_fw_head);
488
489/* reboot notifier for avoid deadlock with usermode_lock */
490static int fw_shutdown_notify(struct notifier_block *unused1,
491			      unsigned long unused2, void *unused3)
492{
493	mutex_lock(&fw_lock);
494	while (!list_empty(&pending_fw_head))
495		__fw_load_abort(list_first_entry(&pending_fw_head,
496					       struct firmware_buf,
497					       pending_list));
498	mutex_unlock(&fw_lock);
499	return NOTIFY_DONE;
500}
501
502static struct notifier_block fw_shutdown_nb = {
503	.notifier_call = fw_shutdown_notify,
504};
505
506static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
507			    char *buf)
508{
509	return sprintf(buf, "%d\n", loading_timeout);
510}
511
512/**
513 * firmware_timeout_store - set number of seconds to wait for firmware
514 * @class: device class pointer
515 * @attr: device attribute pointer
516 * @buf: buffer to scan for timeout value
517 * @count: number of bytes in @buf
518 *
519 *	Sets the number of seconds to wait for the firmware.  Once
520 *	this expires an error will be returned to the driver and no
521 *	firmware will be provided.
522 *
523 *	Note: zero means 'wait forever'.
524 **/
525static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
526			     const char *buf, size_t count)
527{
528	loading_timeout = simple_strtol(buf, NULL, 10);
529	if (loading_timeout < 0)
530		loading_timeout = 0;
531
532	return count;
533}
534
535static struct class_attribute firmware_class_attrs[] = {
536	__ATTR_RW(timeout),
537	__ATTR_NULL
538};
539
540static void fw_dev_release(struct device *dev)
541{
542	struct firmware_priv *fw_priv = to_firmware_priv(dev);
543
544	kfree(fw_priv);
545}
546
547static int do_firmware_uevent(struct firmware_priv *fw_priv, struct kobj_uevent_env *env)
548{
549	if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
550		return -ENOMEM;
551	if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
552		return -ENOMEM;
553	if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
554		return -ENOMEM;
555
556	return 0;
557}
558
559static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
560{
561	struct firmware_priv *fw_priv = to_firmware_priv(dev);
562	int err = 0;
563
564	mutex_lock(&fw_lock);
565	if (fw_priv->buf)
566		err = do_firmware_uevent(fw_priv, env);
567	mutex_unlock(&fw_lock);
568	return err;
569}
570
571static struct class firmware_class = {
572	.name		= "firmware",
573	.class_attrs	= firmware_class_attrs,
574	.dev_uevent	= firmware_uevent,
575	.dev_release	= fw_dev_release,
576};
577
578static ssize_t firmware_loading_show(struct device *dev,
579				     struct device_attribute *attr, char *buf)
580{
581	struct firmware_priv *fw_priv = to_firmware_priv(dev);
582	int loading = 0;
583
584	mutex_lock(&fw_lock);
585	if (fw_priv->buf)
586		loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
587	mutex_unlock(&fw_lock);
588
589	return sprintf(buf, "%d\n", loading);
590}
591
592/* Some architectures don't have PAGE_KERNEL_RO */
593#ifndef PAGE_KERNEL_RO
594#define PAGE_KERNEL_RO PAGE_KERNEL
595#endif
596
597/* one pages buffer should be mapped/unmapped only once */
598static int fw_map_pages_buf(struct firmware_buf *buf)
599{
600	if (!buf->is_paged_buf)
601		return 0;
602
603	vunmap(buf->data);
604	buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
605	if (!buf->data)
606		return -ENOMEM;
607	return 0;
608}
609
610/**
611 * firmware_loading_store - set value in the 'loading' control file
612 * @dev: device pointer
613 * @attr: device attribute pointer
614 * @buf: buffer to scan for loading control value
615 * @count: number of bytes in @buf
616 *
617 *	The relevant values are:
618 *
619 *	 1: Start a load, discarding any previous partial load.
620 *	 0: Conclude the load and hand the data to the driver code.
621 *	-1: Conclude the load with an error and discard any written data.
622 **/
623static ssize_t firmware_loading_store(struct device *dev,
624				      struct device_attribute *attr,
625				      const char *buf, size_t count)
626{
627	struct firmware_priv *fw_priv = to_firmware_priv(dev);
628	struct firmware_buf *fw_buf;
629	ssize_t written = count;
630	int loading = simple_strtol(buf, NULL, 10);
631	int i;
632
633	mutex_lock(&fw_lock);
634	fw_buf = fw_priv->buf;
635	if (!fw_buf)
636		goto out;
637
638	switch (loading) {
639	case 1:
640		/* discarding any previous partial load */
641		if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
642			for (i = 0; i < fw_buf->nr_pages; i++)
643				__free_page(fw_buf->pages[i]);
644			kfree(fw_buf->pages);
645			fw_buf->pages = NULL;
646			fw_buf->page_array_size = 0;
647			fw_buf->nr_pages = 0;
648			set_bit(FW_STATUS_LOADING, &fw_buf->status);
649		}
650		break;
651	case 0:
652		if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
653			int rc;
654
655			set_bit(FW_STATUS_DONE, &fw_buf->status);
656			clear_bit(FW_STATUS_LOADING, &fw_buf->status);
657
658			/*
659			 * Several loading requests may be pending on
660			 * one same firmware buf, so let all requests
661			 * see the mapped 'buf->data' once the loading
662			 * is completed.
663			 * */
664			rc = fw_map_pages_buf(fw_buf);
665			if (rc)
666				dev_err(dev, "%s: map pages failed\n",
667					__func__);
668			else
669				rc = security_kernel_fw_from_file(NULL,
670						fw_buf->data, fw_buf->size);
671
672			/*
673			 * Same logic as fw_load_abort, only the DONE bit
674			 * is ignored and we set ABORT only on failure.
675			 */
676			list_del_init(&fw_buf->pending_list);
677			if (rc) {
678				set_bit(FW_STATUS_ABORT, &fw_buf->status);
679				written = rc;
680			}
681			complete_all(&fw_buf->completion);
682			break;
683		}
684		/* fallthrough */
685	default:
686		dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
687		/* fallthrough */
688	case -1:
689		fw_load_abort(fw_priv);
690		break;
691	}
692out:
693	mutex_unlock(&fw_lock);
694	return written;
695}
696
697static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
698
699static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
700				  struct bin_attribute *bin_attr,
701				  char *buffer, loff_t offset, size_t count)
702{
703	struct device *dev = kobj_to_dev(kobj);
704	struct firmware_priv *fw_priv = to_firmware_priv(dev);
705	struct firmware_buf *buf;
706	ssize_t ret_count;
707
708	mutex_lock(&fw_lock);
709	buf = fw_priv->buf;
710	if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
711		ret_count = -ENODEV;
712		goto out;
713	}
714	if (offset > buf->size) {
715		ret_count = 0;
716		goto out;
717	}
718	if (count > buf->size - offset)
719		count = buf->size - offset;
720
721	ret_count = count;
722
723	while (count) {
724		void *page_data;
725		int page_nr = offset >> PAGE_SHIFT;
726		int page_ofs = offset & (PAGE_SIZE-1);
727		int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
728
729		page_data = kmap(buf->pages[page_nr]);
730
731		memcpy(buffer, page_data + page_ofs, page_cnt);
732
733		kunmap(buf->pages[page_nr]);
734		buffer += page_cnt;
735		offset += page_cnt;
736		count -= page_cnt;
737	}
738out:
739	mutex_unlock(&fw_lock);
740	return ret_count;
741}
742
743static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
744{
745	struct firmware_buf *buf = fw_priv->buf;
746	int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT;
747
748	/* If the array of pages is too small, grow it... */
749	if (buf->page_array_size < pages_needed) {
750		int new_array_size = max(pages_needed,
751					 buf->page_array_size * 2);
752		struct page **new_pages;
753
754		new_pages = kmalloc(new_array_size * sizeof(void *),
755				    GFP_KERNEL);
756		if (!new_pages) {
757			fw_load_abort(fw_priv);
758			return -ENOMEM;
759		}
760		memcpy(new_pages, buf->pages,
761		       buf->page_array_size * sizeof(void *));
762		memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
763		       (new_array_size - buf->page_array_size));
764		kfree(buf->pages);
765		buf->pages = new_pages;
766		buf->page_array_size = new_array_size;
767	}
768
769	while (buf->nr_pages < pages_needed) {
770		buf->pages[buf->nr_pages] =
771			alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
772
773		if (!buf->pages[buf->nr_pages]) {
774			fw_load_abort(fw_priv);
775			return -ENOMEM;
776		}
777		buf->nr_pages++;
778	}
779	return 0;
780}
781
782/**
783 * firmware_data_write - write method for firmware
784 * @filp: open sysfs file
785 * @kobj: kobject for the device
786 * @bin_attr: bin_attr structure
787 * @buffer: buffer being written
788 * @offset: buffer offset for write in total data store area
789 * @count: buffer size
790 *
791 *	Data written to the 'data' attribute will be later handed to
792 *	the driver as a firmware image.
793 **/
794static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
795				   struct bin_attribute *bin_attr,
796				   char *buffer, loff_t offset, size_t count)
797{
798	struct device *dev = kobj_to_dev(kobj);
799	struct firmware_priv *fw_priv = to_firmware_priv(dev);
800	struct firmware_buf *buf;
801	ssize_t retval;
802
803	if (!capable(CAP_SYS_RAWIO))
804		return -EPERM;
805
806	mutex_lock(&fw_lock);
807	buf = fw_priv->buf;
808	if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
809		retval = -ENODEV;
810		goto out;
811	}
812
813	retval = fw_realloc_buffer(fw_priv, offset + count);
814	if (retval)
815		goto out;
816
817	retval = count;
818
819	while (count) {
820		void *page_data;
821		int page_nr = offset >> PAGE_SHIFT;
822		int page_ofs = offset & (PAGE_SIZE - 1);
823		int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
824
825		page_data = kmap(buf->pages[page_nr]);
826
827		memcpy(page_data + page_ofs, buffer, page_cnt);
828
829		kunmap(buf->pages[page_nr]);
830		buffer += page_cnt;
831		offset += page_cnt;
832		count -= page_cnt;
833	}
834
835	buf->size = max_t(size_t, offset, buf->size);
836out:
837	mutex_unlock(&fw_lock);
838	return retval;
839}
840
841static struct bin_attribute firmware_attr_data = {
842	.attr = { .name = "data", .mode = 0644 },
843	.size = 0,
844	.read = firmware_data_read,
845	.write = firmware_data_write,
846};
847
848static struct attribute *fw_dev_attrs[] = {
849	&dev_attr_loading.attr,
850	NULL
851};
852
853static struct bin_attribute *fw_dev_bin_attrs[] = {
854	&firmware_attr_data,
855	NULL
856};
857
858static const struct attribute_group fw_dev_attr_group = {
859	.attrs = fw_dev_attrs,
860	.bin_attrs = fw_dev_bin_attrs,
861};
862
863static const struct attribute_group *fw_dev_attr_groups[] = {
864	&fw_dev_attr_group,
865	NULL
866};
867
868static struct firmware_priv *
869fw_create_instance(struct firmware *firmware, const char *fw_name,
870		   struct device *device, unsigned int opt_flags)
871{
872	struct firmware_priv *fw_priv;
873	struct device *f_dev;
874
875	fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
876	if (!fw_priv) {
877		fw_priv = ERR_PTR(-ENOMEM);
878		goto exit;
879	}
880
881	fw_priv->nowait = !!(opt_flags & FW_OPT_NOWAIT);
882	fw_priv->fw = firmware;
883	f_dev = &fw_priv->dev;
884
885	device_initialize(f_dev);
886	dev_set_name(f_dev, "%s", fw_name);
887	f_dev->parent = device;
888	f_dev->class = &firmware_class;
889	f_dev->groups = fw_dev_attr_groups;
890exit:
891	return fw_priv;
892}
893
894/* load a firmware via user helper */
895static int _request_firmware_load(struct firmware_priv *fw_priv,
896				  unsigned int opt_flags, long timeout)
897{
898	int retval = 0;
899	struct device *f_dev = &fw_priv->dev;
900	struct firmware_buf *buf = fw_priv->buf;
901
902	/* fall back on userspace loading */
903	buf->is_paged_buf = true;
904
905	dev_set_uevent_suppress(f_dev, true);
906
907	retval = device_add(f_dev);
908	if (retval) {
909		dev_err(f_dev, "%s: device_register failed\n", __func__);
910		goto err_put_dev;
911	}
912
913	mutex_lock(&fw_lock);
914	list_add(&buf->pending_list, &pending_fw_head);
915	mutex_unlock(&fw_lock);
916
917	if (opt_flags & FW_OPT_UEVENT) {
918		buf->need_uevent = true;
919		dev_set_uevent_suppress(f_dev, false);
920		dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
921		kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
922	} else {
923		timeout = MAX_JIFFY_OFFSET;
924	}
925
926	retval = wait_for_completion_interruptible_timeout(&buf->completion,
927			timeout);
928	if (retval == -ERESTARTSYS || !retval) {
929		mutex_lock(&fw_lock);
930		fw_load_abort(fw_priv);
931		mutex_unlock(&fw_lock);
932	} else if (retval > 0) {
933		retval = 0;
934	}
935
936	if (is_fw_load_aborted(buf))
937		retval = -EAGAIN;
938	else if (!buf->data)
939		retval = -ENOMEM;
940
941	device_del(f_dev);
942err_put_dev:
943	put_device(f_dev);
944	return retval;
945}
946
947static int fw_load_from_user_helper(struct firmware *firmware,
948				    const char *name, struct device *device,
949				    unsigned int opt_flags, long timeout)
950{
951	struct firmware_priv *fw_priv;
952
953	fw_priv = fw_create_instance(firmware, name, device, opt_flags);
954	if (IS_ERR(fw_priv))
955		return PTR_ERR(fw_priv);
956
957	fw_priv->buf = firmware->priv;
958	return _request_firmware_load(fw_priv, opt_flags, timeout);
959}
960
961#ifdef CONFIG_PM_SLEEP
962/* kill pending requests without uevent to avoid blocking suspend */
963static void kill_requests_without_uevent(void)
964{
965	struct firmware_buf *buf;
966	struct firmware_buf *next;
967
968	mutex_lock(&fw_lock);
969	list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
970		if (!buf->need_uevent)
971			 __fw_load_abort(buf);
972	}
973	mutex_unlock(&fw_lock);
974}
975#endif
976
977#else /* CONFIG_FW_LOADER_USER_HELPER */
978static inline int
979fw_load_from_user_helper(struct firmware *firmware, const char *name,
980			 struct device *device, unsigned int opt_flags,
981			 long timeout)
982{
983	return -ENOENT;
984}
985
986/* No abort during direct loading */
987#define is_fw_load_aborted(buf) false
988
989#ifdef CONFIG_PM_SLEEP
990static inline void kill_requests_without_uevent(void) { }
991#endif
992
993#endif /* CONFIG_FW_LOADER_USER_HELPER */
994
995
996/* wait until the shared firmware_buf becomes ready (or error) */
997static int sync_cached_firmware_buf(struct firmware_buf *buf)
998{
999	int ret = 0;
1000
1001	mutex_lock(&fw_lock);
1002	while (!test_bit(FW_STATUS_DONE, &buf->status)) {
1003		if (is_fw_load_aborted(buf)) {
1004			ret = -ENOENT;
1005			break;
1006		}
1007		mutex_unlock(&fw_lock);
1008		ret = wait_for_completion_interruptible(&buf->completion);
1009		mutex_lock(&fw_lock);
1010	}
1011	mutex_unlock(&fw_lock);
1012	return ret;
1013}
1014
1015/* prepare firmware and firmware_buf structs;
1016 * return 0 if a firmware is already assigned, 1 if need to load one,
1017 * or a negative error code
1018 */
1019static int
1020_request_firmware_prepare(struct firmware **firmware_p, const char *name,
1021			  struct device *device)
1022{
1023	struct firmware *firmware;
1024	struct firmware_buf *buf;
1025	int ret;
1026
1027	*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
1028	if (!firmware) {
1029		dev_err(device, "%s: kmalloc(struct firmware) failed\n",
1030			__func__);
1031		return -ENOMEM;
1032	}
1033
1034	if (fw_get_builtin_firmware(firmware, name)) {
1035		dev_dbg(device, "firmware: using built-in firmware %s\n", name);
1036		return 0; /* assigned */
1037	}
1038
1039	ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
1040
1041	/*
1042	 * bind with 'buf' now to avoid warning in failure path
1043	 * of requesting firmware.
1044	 */
1045	firmware->priv = buf;
1046
1047	if (ret > 0) {
1048		ret = sync_cached_firmware_buf(buf);
1049		if (!ret) {
1050			fw_set_page_data(buf, firmware);
1051			return 0; /* assigned */
1052		}
1053	}
1054
1055	if (ret < 0)
1056		return ret;
1057	return 1; /* need to load */
1058}
1059
1060static int assign_firmware_buf(struct firmware *fw, struct device *device,
1061			       unsigned int opt_flags)
1062{
1063	struct firmware_buf *buf = fw->priv;
1064
1065	mutex_lock(&fw_lock);
1066	if (!buf->size || is_fw_load_aborted(buf)) {
1067		mutex_unlock(&fw_lock);
1068		return -ENOENT;
1069	}
1070
1071	/*
1072	 * add firmware name into devres list so that we can auto cache
1073	 * and uncache firmware for device.
1074	 *
1075	 * device may has been deleted already, but the problem
1076	 * should be fixed in devres or driver core.
1077	 */
1078	/* don't cache firmware handled without uevent */
1079	if (device && (opt_flags & FW_OPT_UEVENT))
1080		fw_add_devm_name(device, buf->fw_id);
1081
1082	/*
1083	 * After caching firmware image is started, let it piggyback
1084	 * on request firmware.
1085	 */
1086	if (buf->fwc->state == FW_LOADER_START_CACHE) {
1087		if (fw_cache_piggyback_on_request(buf->fw_id))
1088			kref_get(&buf->ref);
1089	}
1090
1091	/* pass the pages buffer to driver at the last minute */
1092	fw_set_page_data(buf, fw);
1093	mutex_unlock(&fw_lock);
1094	return 0;
1095}
1096
1097/* called from request_firmware() and request_firmware_work_func() */
1098static int
1099_request_firmware(const struct firmware **firmware_p, const char *name,
1100		  struct device *device, unsigned int opt_flags)
1101{
1102	struct firmware *fw;
1103	long timeout;
1104	int ret;
1105
1106	if (!firmware_p)
1107		return -EINVAL;
1108
1109	if (!name || name[0] == '\0')
1110		return -EINVAL;
1111
1112	ret = _request_firmware_prepare(&fw, name, device);
1113	if (ret <= 0) /* error or already assigned */
1114		goto out;
1115
1116	ret = 0;
1117	timeout = firmware_loading_timeout();
1118	if (opt_flags & FW_OPT_NOWAIT) {
1119		timeout = usermodehelper_read_lock_wait(timeout);
1120		if (!timeout) {
1121			dev_dbg(device, "firmware: %s loading timed out\n",
1122				name);
1123			ret = -EBUSY;
1124			goto out;
1125		}
1126	} else {
1127		ret = usermodehelper_read_trylock();
1128		if (WARN_ON(ret)) {
1129			dev_err(device, "firmware: %s will not be loaded\n",
1130				name);
1131			goto out;
1132		}
1133	}
1134
1135	ret = fw_get_filesystem_firmware(device, fw->priv);
1136	if (ret) {
1137		if (!(opt_flags & FW_OPT_NO_WARN))
1138			dev_warn(device,
1139				 "Direct firmware load for %s failed with error %d\n",
1140				 name, ret);
1141		if (opt_flags & FW_OPT_USERHELPER) {
1142			dev_warn(device, "Falling back to user helper\n");
1143			ret = fw_load_from_user_helper(fw, name, device,
1144						       opt_flags, timeout);
1145		}
1146	}
1147
1148	if (!ret)
1149		ret = assign_firmware_buf(fw, device, opt_flags);
1150
1151	usermodehelper_read_unlock();
1152
1153 out:
1154	if (ret < 0) {
1155		release_firmware(fw);
1156		fw = NULL;
1157	}
1158
1159	*firmware_p = fw;
1160	return ret;
1161}
1162
1163/**
1164 * request_firmware: - send firmware request and wait for it
1165 * @firmware_p: pointer to firmware image
1166 * @name: name of firmware file
1167 * @device: device for which firmware is being loaded
1168 *
1169 *      @firmware_p will be used to return a firmware image by the name
1170 *      of @name for device @device.
1171 *
1172 *      Should be called from user context where sleeping is allowed.
1173 *
1174 *      @name will be used as $FIRMWARE in the uevent environment and
1175 *      should be distinctive enough not to be confused with any other
1176 *      firmware image for this or any other device.
1177 *
1178 *	Caller must hold the reference count of @device.
1179 *
1180 *	The function can be called safely inside device's suspend and
1181 *	resume callback.
1182 **/
1183int
1184request_firmware(const struct firmware **firmware_p, const char *name,
1185		 struct device *device)
1186{
1187	int ret;
1188
1189	/* Need to pin this module until return */
1190	__module_get(THIS_MODULE);
1191	ret = _request_firmware(firmware_p, name, device,
1192				FW_OPT_UEVENT | FW_OPT_FALLBACK);
1193	module_put(THIS_MODULE);
1194	return ret;
1195}
1196EXPORT_SYMBOL(request_firmware);
1197
1198/**
1199 * request_firmware_direct: - load firmware directly without usermode helper
1200 * @firmware_p: pointer to firmware image
1201 * @name: name of firmware file
1202 * @device: device for which firmware is being loaded
1203 *
1204 * This function works pretty much like request_firmware(), but this doesn't
1205 * fall back to usermode helper even if the firmware couldn't be loaded
1206 * directly from fs.  Hence it's useful for loading optional firmwares, which
1207 * aren't always present, without extra long timeouts of udev.
1208 **/
1209int request_firmware_direct(const struct firmware **firmware_p,
1210			    const char *name, struct device *device)
1211{
1212	int ret;
1213
1214	__module_get(THIS_MODULE);
1215	ret = _request_firmware(firmware_p, name, device,
1216				FW_OPT_UEVENT | FW_OPT_NO_WARN);
1217	module_put(THIS_MODULE);
1218	return ret;
1219}
1220EXPORT_SYMBOL_GPL(request_firmware_direct);
1221
1222/**
1223 * release_firmware: - release the resource associated with a firmware image
1224 * @fw: firmware resource to release
1225 **/
1226void release_firmware(const struct firmware *fw)
1227{
1228	if (fw) {
1229		if (!fw_is_builtin_firmware(fw))
1230			firmware_free_data(fw);
1231		kfree(fw);
1232	}
1233}
1234EXPORT_SYMBOL(release_firmware);
1235
1236/* Async support */
1237struct firmware_work {
1238	struct work_struct work;
1239	struct module *module;
1240	const char *name;
1241	struct device *device;
1242	void *context;
1243	void (*cont)(const struct firmware *fw, void *context);
1244	unsigned int opt_flags;
1245};
1246
1247static void request_firmware_work_func(struct work_struct *work)
1248{
1249	struct firmware_work *fw_work;
1250	const struct firmware *fw;
1251
1252	fw_work = container_of(work, struct firmware_work, work);
1253
1254	_request_firmware(&fw, fw_work->name, fw_work->device,
1255			  fw_work->opt_flags);
1256	fw_work->cont(fw, fw_work->context);
1257	put_device(fw_work->device); /* taken in request_firmware_nowait() */
1258
1259	module_put(fw_work->module);
1260	kfree(fw_work);
1261}
1262
1263/**
1264 * request_firmware_nowait - asynchronous version of request_firmware
1265 * @module: module requesting the firmware
1266 * @uevent: sends uevent to copy the firmware image if this flag
1267 *	is non-zero else the firmware copy must be done manually.
1268 * @name: name of firmware file
1269 * @device: device for which firmware is being loaded
1270 * @gfp: allocation flags
1271 * @context: will be passed over to @cont, and
1272 *	@fw may be %NULL if firmware request fails.
1273 * @cont: function will be called asynchronously when the firmware
1274 *	request is over.
1275 *
1276 *	Caller must hold the reference count of @device.
1277 *
1278 *	Asynchronous variant of request_firmware() for user contexts:
1279 *		- sleep for as small periods as possible since it may
1280 *		increase kernel boot time of built-in device drivers
1281 *		requesting firmware in their ->probe() methods, if
1282 *		@gfp is GFP_KERNEL.
1283 *
1284 *		- can't sleep at all if @gfp is GFP_ATOMIC.
1285 **/
1286int
1287request_firmware_nowait(
1288	struct module *module, bool uevent,
1289	const char *name, struct device *device, gfp_t gfp, void *context,
1290	void (*cont)(const struct firmware *fw, void *context))
1291{
1292	struct firmware_work *fw_work;
1293
1294	fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1295	if (!fw_work)
1296		return -ENOMEM;
1297
1298	fw_work->module = module;
1299	fw_work->name = name;
1300	fw_work->device = device;
1301	fw_work->context = context;
1302	fw_work->cont = cont;
1303	fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
1304		(uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1305
1306	if (!try_module_get(module)) {
1307		kfree(fw_work);
1308		return -EFAULT;
1309	}
1310
1311	get_device(fw_work->device);
1312	INIT_WORK(&fw_work->work, request_firmware_work_func);
1313	schedule_work(&fw_work->work);
1314	return 0;
1315}
1316EXPORT_SYMBOL(request_firmware_nowait);
1317
1318#ifdef CONFIG_PM_SLEEP
1319static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1320
1321/**
1322 * cache_firmware - cache one firmware image in kernel memory space
1323 * @fw_name: the firmware image name
1324 *
1325 * Cache firmware in kernel memory so that drivers can use it when
1326 * system isn't ready for them to request firmware image from userspace.
1327 * Once it returns successfully, driver can use request_firmware or its
1328 * nowait version to get the cached firmware without any interacting
1329 * with userspace
1330 *
1331 * Return 0 if the firmware image has been cached successfully
1332 * Return !0 otherwise
1333 *
1334 */
1335static int cache_firmware(const char *fw_name)
1336{
1337	int ret;
1338	const struct firmware *fw;
1339
1340	pr_debug("%s: %s\n", __func__, fw_name);
1341
1342	ret = request_firmware(&fw, fw_name, NULL);
1343	if (!ret)
1344		kfree(fw);
1345
1346	pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1347
1348	return ret;
1349}
1350
1351static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1352{
1353	struct firmware_buf *tmp;
1354	struct firmware_cache *fwc = &fw_cache;
1355
1356	spin_lock(&fwc->lock);
1357	tmp = __fw_lookup_buf(fw_name);
1358	spin_unlock(&fwc->lock);
1359
1360	return tmp;
1361}
1362
1363/**
1364 * uncache_firmware - remove one cached firmware image
1365 * @fw_name: the firmware image name
1366 *
1367 * Uncache one firmware image which has been cached successfully
1368 * before.
1369 *
1370 * Return 0 if the firmware cache has been removed successfully
1371 * Return !0 otherwise
1372 *
1373 */
1374static int uncache_firmware(const char *fw_name)
1375{
1376	struct firmware_buf *buf;
1377	struct firmware fw;
1378
1379	pr_debug("%s: %s\n", __func__, fw_name);
1380
1381	if (fw_get_builtin_firmware(&fw, fw_name))
1382		return 0;
1383
1384	buf = fw_lookup_buf(fw_name);
1385	if (buf) {
1386		fw_free_buf(buf);
1387		return 0;
1388	}
1389
1390	return -EINVAL;
1391}
1392
1393static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1394{
1395	struct fw_cache_entry *fce;
1396
1397	fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1398	if (!fce)
1399		goto exit;
1400
1401	strcpy(fce->name, name);
1402exit:
1403	return fce;
1404}
1405
1406static int __fw_entry_found(const char *name)
1407{
1408	struct firmware_cache *fwc = &fw_cache;
1409	struct fw_cache_entry *fce;
1410
1411	list_for_each_entry(fce, &fwc->fw_names, list) {
1412		if (!strcmp(fce->name, name))
1413			return 1;
1414	}
1415	return 0;
1416}
1417
1418static int fw_cache_piggyback_on_request(const char *name)
1419{
1420	struct firmware_cache *fwc = &fw_cache;
1421	struct fw_cache_entry *fce;
1422	int ret = 0;
1423
1424	spin_lock(&fwc->name_lock);
1425	if (__fw_entry_found(name))
1426		goto found;
1427
1428	fce = alloc_fw_cache_entry(name);
1429	if (fce) {
1430		ret = 1;
1431		list_add(&fce->list, &fwc->fw_names);
1432		pr_debug("%s: fw: %s\n", __func__, name);
1433	}
1434found:
1435	spin_unlock(&fwc->name_lock);
1436	return ret;
1437}
1438
1439static void free_fw_cache_entry(struct fw_cache_entry *fce)
1440{
1441	kfree(fce);
1442}
1443
1444static void __async_dev_cache_fw_image(void *fw_entry,
1445				       async_cookie_t cookie)
1446{
1447	struct fw_cache_entry *fce = fw_entry;
1448	struct firmware_cache *fwc = &fw_cache;
1449	int ret;
1450
1451	ret = cache_firmware(fce->name);
1452	if (ret) {
1453		spin_lock(&fwc->name_lock);
1454		list_del(&fce->list);
1455		spin_unlock(&fwc->name_lock);
1456
1457		free_fw_cache_entry(fce);
1458	}
1459}
1460
1461/* called with dev->devres_lock held */
1462static void dev_create_fw_entry(struct device *dev, void *res,
1463				void *data)
1464{
1465	struct fw_name_devm *fwn = res;
1466	const char *fw_name = fwn->name;
1467	struct list_head *head = data;
1468	struct fw_cache_entry *fce;
1469
1470	fce = alloc_fw_cache_entry(fw_name);
1471	if (fce)
1472		list_add(&fce->list, head);
1473}
1474
1475static int devm_name_match(struct device *dev, void *res,
1476			   void *match_data)
1477{
1478	struct fw_name_devm *fwn = res;
1479	return (fwn->magic == (unsigned long)match_data);
1480}
1481
1482static void dev_cache_fw_image(struct device *dev, void *data)
1483{
1484	LIST_HEAD(todo);
1485	struct fw_cache_entry *fce;
1486	struct fw_cache_entry *fce_next;
1487	struct firmware_cache *fwc = &fw_cache;
1488
1489	devres_for_each_res(dev, fw_name_devm_release,
1490			    devm_name_match, &fw_cache,
1491			    dev_create_fw_entry, &todo);
1492
1493	list_for_each_entry_safe(fce, fce_next, &todo, list) {
1494		list_del(&fce->list);
1495
1496		spin_lock(&fwc->name_lock);
1497		/* only one cache entry for one firmware */
1498		if (!__fw_entry_found(fce->name)) {
1499			list_add(&fce->list, &fwc->fw_names);
1500		} else {
1501			free_fw_cache_entry(fce);
1502			fce = NULL;
1503		}
1504		spin_unlock(&fwc->name_lock);
1505
1506		if (fce)
1507			async_schedule_domain(__async_dev_cache_fw_image,
1508					      (void *)fce,
1509					      &fw_cache_domain);
1510	}
1511}
1512
1513static void __device_uncache_fw_images(void)
1514{
1515	struct firmware_cache *fwc = &fw_cache;
1516	struct fw_cache_entry *fce;
1517
1518	spin_lock(&fwc->name_lock);
1519	while (!list_empty(&fwc->fw_names)) {
1520		fce = list_entry(fwc->fw_names.next,
1521				struct fw_cache_entry, list);
1522		list_del(&fce->list);
1523		spin_unlock(&fwc->name_lock);
1524
1525		uncache_firmware(fce->name);
1526		free_fw_cache_entry(fce);
1527
1528		spin_lock(&fwc->name_lock);
1529	}
1530	spin_unlock(&fwc->name_lock);
1531}
1532
1533/**
1534 * device_cache_fw_images - cache devices' firmware
1535 *
1536 * If one device called request_firmware or its nowait version
1537 * successfully before, the firmware names are recored into the
1538 * device's devres link list, so device_cache_fw_images can call
1539 * cache_firmware() to cache these firmwares for the device,
1540 * then the device driver can load its firmwares easily at
1541 * time when system is not ready to complete loading firmware.
1542 */
1543static void device_cache_fw_images(void)
1544{
1545	struct firmware_cache *fwc = &fw_cache;
1546	int old_timeout;
1547	DEFINE_WAIT(wait);
1548
1549	pr_debug("%s\n", __func__);
1550
1551	/* cancel uncache work */
1552	cancel_delayed_work_sync(&fwc->work);
1553
1554	/*
1555	 * use small loading timeout for caching devices' firmware
1556	 * because all these firmware images have been loaded
1557	 * successfully at lease once, also system is ready for
1558	 * completing firmware loading now. The maximum size of
1559	 * firmware in current distributions is about 2M bytes,
1560	 * so 10 secs should be enough.
1561	 */
1562	old_timeout = loading_timeout;
1563	loading_timeout = 10;
1564
1565	mutex_lock(&fw_lock);
1566	fwc->state = FW_LOADER_START_CACHE;
1567	dpm_for_each_dev(NULL, dev_cache_fw_image);
1568	mutex_unlock(&fw_lock);
1569
1570	/* wait for completion of caching firmware for all devices */
1571	async_synchronize_full_domain(&fw_cache_domain);
1572
1573	loading_timeout = old_timeout;
1574}
1575
1576/**
1577 * device_uncache_fw_images - uncache devices' firmware
1578 *
1579 * uncache all firmwares which have been cached successfully
1580 * by device_uncache_fw_images earlier
1581 */
1582static void device_uncache_fw_images(void)
1583{
1584	pr_debug("%s\n", __func__);
1585	__device_uncache_fw_images();
1586}
1587
1588static void device_uncache_fw_images_work(struct work_struct *work)
1589{
1590	device_uncache_fw_images();
1591}
1592
1593/**
1594 * device_uncache_fw_images_delay - uncache devices firmwares
1595 * @delay: number of milliseconds to delay uncache device firmwares
1596 *
1597 * uncache all devices's firmwares which has been cached successfully
1598 * by device_cache_fw_images after @delay milliseconds.
1599 */
1600static void device_uncache_fw_images_delay(unsigned long delay)
1601{
1602	queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1603			   msecs_to_jiffies(delay));
1604}
1605
1606static int fw_pm_notify(struct notifier_block *notify_block,
1607			unsigned long mode, void *unused)
1608{
1609	switch (mode) {
1610	case PM_HIBERNATION_PREPARE:
1611	case PM_SUSPEND_PREPARE:
1612	case PM_RESTORE_PREPARE:
1613		kill_requests_without_uevent();
1614		device_cache_fw_images();
1615		break;
1616
1617	case PM_POST_SUSPEND:
1618	case PM_POST_HIBERNATION:
1619	case PM_POST_RESTORE:
1620		/*
1621		 * In case that system sleep failed and syscore_suspend is
1622		 * not called.
1623		 */
1624		mutex_lock(&fw_lock);
1625		fw_cache.state = FW_LOADER_NO_CACHE;
1626		mutex_unlock(&fw_lock);
1627
1628		device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1629		break;
1630	}
1631
1632	return 0;
1633}
1634
1635/* stop caching firmware once syscore_suspend is reached */
1636static int fw_suspend(void)
1637{
1638	fw_cache.state = FW_LOADER_NO_CACHE;
1639	return 0;
1640}
1641
1642static struct syscore_ops fw_syscore_ops = {
1643	.suspend = fw_suspend,
1644};
1645#else
1646static int fw_cache_piggyback_on_request(const char *name)
1647{
1648	return 0;
1649}
1650#endif
1651
1652static void __init fw_cache_init(void)
1653{
1654	spin_lock_init(&fw_cache.lock);
1655	INIT_LIST_HEAD(&fw_cache.head);
1656	fw_cache.state = FW_LOADER_NO_CACHE;
1657
1658#ifdef CONFIG_PM_SLEEP
1659	spin_lock_init(&fw_cache.name_lock);
1660	INIT_LIST_HEAD(&fw_cache.fw_names);
1661
1662	INIT_DELAYED_WORK(&fw_cache.work,
1663			  device_uncache_fw_images_work);
1664
1665	fw_cache.pm_notify.notifier_call = fw_pm_notify;
1666	register_pm_notifier(&fw_cache.pm_notify);
1667
1668	register_syscore_ops(&fw_syscore_ops);
1669#endif
1670}
1671
1672static int __init firmware_class_init(void)
1673{
1674	fw_cache_init();
1675#ifdef CONFIG_FW_LOADER_USER_HELPER
1676	register_reboot_notifier(&fw_shutdown_nb);
1677	return class_register(&firmware_class);
1678#else
1679	return 0;
1680#endif
1681}
1682
1683static void __exit firmware_class_exit(void)
1684{
1685#ifdef CONFIG_PM_SLEEP
1686	unregister_syscore_ops(&fw_syscore_ops);
1687	unregister_pm_notifier(&fw_cache.pm_notify);
1688#endif
1689#ifdef CONFIG_FW_LOADER_USER_HELPER
1690	unregister_reboot_notifier(&fw_shutdown_nb);
1691	class_unregister(&firmware_class);
1692#endif
1693}
1694
1695fs_initcall(firmware_class_init);
1696module_exit(firmware_class_exit);
1697