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>
25 #define to_dev(obj) container_of(obj, struct device, kobj)
27 MODULE_AUTHOR("Manuel Estrada Sainz");
28 MODULE_DESCRIPTION("Multi purpose firmware loading support");
29 MODULE_LICENSE("GPL");
31 /* Builtin firmware support */
33 #ifdef CONFIG_FW_LOADER
35 extern struct builtin_fw __start_builtin_fw[];
36 extern struct builtin_fw __end_builtin_fw[];
38 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
40 struct builtin_fw *b_fw;
42 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
43 if (strcmp(name, b_fw->name) == 0) {
44 fw->size = b_fw->size;
45 fw->data = b_fw->data;
53 static bool fw_is_builtin_firmware(const struct firmware *fw)
55 struct builtin_fw *b_fw;
57 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
58 if (fw->data == b_fw->data)
64 #else /* Module case - no builtin firmware support */
66 static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
71 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
83 static int loading_timeout = 60; /* In seconds */
85 static inline long firmware_loading_timeout(void)
87 return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
90 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
91 * guarding for corner cases a global lock should be OK */
92 static DEFINE_MUTEX(fw_lock);
94 struct firmware_priv {
95 struct completion completion;
101 struct timer_list timeout;
107 static struct firmware_priv *to_firmware_priv(struct device *dev)
109 return container_of(dev, struct firmware_priv, dev);
112 static void fw_load_abort(struct firmware_priv *fw_priv)
114 set_bit(FW_STATUS_ABORT, &fw_priv->status);
116 complete(&fw_priv->completion);
119 static ssize_t firmware_timeout_show(struct class *class,
120 struct class_attribute *attr,
123 return sprintf(buf, "%d\n", loading_timeout);
127 * firmware_timeout_store - set number of seconds to wait for firmware
128 * @class: device class pointer
129 * @attr: device attribute pointer
130 * @buf: buffer to scan for timeout value
131 * @count: number of bytes in @buf
133 * Sets the number of seconds to wait for the firmware. Once
134 * this expires an error will be returned to the driver and no
135 * firmware will be provided.
137 * Note: zero means 'wait forever'.
139 static ssize_t firmware_timeout_store(struct class *class,
140 struct class_attribute *attr,
141 const char *buf, size_t count)
143 loading_timeout = simple_strtol(buf, NULL, 10);
144 if (loading_timeout < 0)
150 static struct class_attribute firmware_class_attrs[] = {
151 __ATTR(timeout, S_IWUSR | S_IRUGO,
152 firmware_timeout_show, firmware_timeout_store),
156 static void fw_dev_release(struct device *dev)
158 struct firmware_priv *fw_priv = to_firmware_priv(dev);
161 for (i = 0; i < fw_priv->nr_pages; i++)
162 __free_page(fw_priv->pages[i]);
163 kfree(fw_priv->pages);
166 module_put(THIS_MODULE);
169 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
171 struct firmware_priv *fw_priv = to_firmware_priv(dev);
173 if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->fw_id))
175 if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
177 if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
183 static struct class firmware_class = {
185 .class_attrs = firmware_class_attrs,
186 .dev_uevent = firmware_uevent,
187 .dev_release = fw_dev_release,
190 static ssize_t firmware_loading_show(struct device *dev,
191 struct device_attribute *attr, char *buf)
193 struct firmware_priv *fw_priv = to_firmware_priv(dev);
194 int loading = test_bit(FW_STATUS_LOADING, &fw_priv->status);
196 return sprintf(buf, "%d\n", loading);
199 static void firmware_free_data(const struct firmware *fw)
204 for (i = 0; i < PFN_UP(fw->size); i++)
205 __free_page(fw->pages[i]);
210 /* Some architectures don't have PAGE_KERNEL_RO */
211 #ifndef PAGE_KERNEL_RO
212 #define PAGE_KERNEL_RO PAGE_KERNEL
215 * firmware_loading_store - set value in the 'loading' control file
216 * @dev: device pointer
217 * @attr: device attribute pointer
218 * @buf: buffer to scan for loading control value
219 * @count: number of bytes in @buf
221 * The relevant values are:
223 * 1: Start a load, discarding any previous partial load.
224 * 0: Conclude the load and hand the data to the driver code.
225 * -1: Conclude the load with an error and discard any written data.
227 static ssize_t firmware_loading_store(struct device *dev,
228 struct device_attribute *attr,
229 const char *buf, size_t count)
231 struct firmware_priv *fw_priv = to_firmware_priv(dev);
232 int loading = simple_strtol(buf, NULL, 10);
235 mutex_lock(&fw_lock);
242 firmware_free_data(fw_priv->fw);
243 memset(fw_priv->fw, 0, sizeof(struct firmware));
244 /* If the pages are not owned by 'struct firmware' */
245 for (i = 0; i < fw_priv->nr_pages; i++)
246 __free_page(fw_priv->pages[i]);
247 kfree(fw_priv->pages);
248 fw_priv->pages = NULL;
249 fw_priv->page_array_size = 0;
250 fw_priv->nr_pages = 0;
251 set_bit(FW_STATUS_LOADING, &fw_priv->status);
254 if (test_bit(FW_STATUS_LOADING, &fw_priv->status)) {
255 vunmap(fw_priv->fw->data);
256 fw_priv->fw->data = vmap(fw_priv->pages,
259 if (!fw_priv->fw->data) {
260 dev_err(dev, "%s: vmap() failed\n", __func__);
263 /* Pages are now owned by 'struct firmware' */
264 fw_priv->fw->pages = fw_priv->pages;
265 fw_priv->pages = NULL;
267 fw_priv->page_array_size = 0;
268 fw_priv->nr_pages = 0;
269 complete(&fw_priv->completion);
270 clear_bit(FW_STATUS_LOADING, &fw_priv->status);
275 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
279 fw_load_abort(fw_priv);
283 mutex_unlock(&fw_lock);
287 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
289 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
290 struct bin_attribute *bin_attr,
291 char *buffer, loff_t offset, size_t count)
293 struct device *dev = to_dev(kobj);
294 struct firmware_priv *fw_priv = to_firmware_priv(dev);
298 mutex_lock(&fw_lock);
300 if (!fw || test_bit(FW_STATUS_DONE, &fw_priv->status)) {
304 if (offset > fw->size) {
308 if (count > fw->size - offset)
309 count = fw->size - offset;
315 int page_nr = offset >> PAGE_SHIFT;
316 int page_ofs = offset & (PAGE_SIZE-1);
317 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
319 page_data = kmap(fw_priv->pages[page_nr]);
321 memcpy(buffer, page_data + page_ofs, page_cnt);
323 kunmap(fw_priv->pages[page_nr]);
329 mutex_unlock(&fw_lock);
333 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
335 int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
337 /* If the array of pages is too small, grow it... */
338 if (fw_priv->page_array_size < pages_needed) {
339 int new_array_size = max(pages_needed,
340 fw_priv->page_array_size * 2);
341 struct page **new_pages;
343 new_pages = kmalloc(new_array_size * sizeof(void *),
346 fw_load_abort(fw_priv);
349 memcpy(new_pages, fw_priv->pages,
350 fw_priv->page_array_size * sizeof(void *));
351 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
352 (new_array_size - fw_priv->page_array_size));
353 kfree(fw_priv->pages);
354 fw_priv->pages = new_pages;
355 fw_priv->page_array_size = new_array_size;
358 while (fw_priv->nr_pages < pages_needed) {
359 fw_priv->pages[fw_priv->nr_pages] =
360 alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
362 if (!fw_priv->pages[fw_priv->nr_pages]) {
363 fw_load_abort(fw_priv);
372 * firmware_data_write - write method for firmware
373 * @filp: open sysfs file
374 * @kobj: kobject for the device
375 * @bin_attr: bin_attr structure
376 * @buffer: buffer being written
377 * @offset: buffer offset for write in total data store area
378 * @count: buffer size
380 * Data written to the 'data' attribute will be later handed to
381 * the driver as a firmware image.
383 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
384 struct bin_attribute *bin_attr,
385 char *buffer, loff_t offset, size_t count)
387 struct device *dev = to_dev(kobj);
388 struct firmware_priv *fw_priv = to_firmware_priv(dev);
392 if (!capable(CAP_SYS_RAWIO))
395 mutex_lock(&fw_lock);
397 if (!fw || test_bit(FW_STATUS_DONE, &fw_priv->status)) {
401 retval = fw_realloc_buffer(fw_priv, offset + count);
409 int page_nr = offset >> PAGE_SHIFT;
410 int page_ofs = offset & (PAGE_SIZE - 1);
411 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
413 page_data = kmap(fw_priv->pages[page_nr]);
415 memcpy(page_data + page_ofs, buffer, page_cnt);
417 kunmap(fw_priv->pages[page_nr]);
423 fw->size = max_t(size_t, offset, fw->size);
425 mutex_unlock(&fw_lock);
429 static struct bin_attribute firmware_attr_data = {
430 .attr = { .name = "data", .mode = 0644 },
432 .read = firmware_data_read,
433 .write = firmware_data_write,
436 static void firmware_class_timeout(u_long data)
438 struct firmware_priv *fw_priv = (struct firmware_priv *) data;
440 fw_load_abort(fw_priv);
443 static struct firmware_priv *
444 fw_create_instance(struct firmware *firmware, const char *fw_name,
445 struct device *device, bool uevent, bool nowait)
447 struct firmware_priv *fw_priv;
448 struct device *f_dev;
450 fw_priv = kzalloc(sizeof(*fw_priv) + strlen(fw_name) + 1 , GFP_KERNEL);
452 dev_err(device, "%s: kmalloc failed\n", __func__);
453 return ERR_PTR(-ENOMEM);
456 fw_priv->fw = firmware;
457 fw_priv->nowait = nowait;
458 strcpy(fw_priv->fw_id, fw_name);
459 init_completion(&fw_priv->completion);
460 setup_timer(&fw_priv->timeout,
461 firmware_class_timeout, (u_long) fw_priv);
463 f_dev = &fw_priv->dev;
465 device_initialize(f_dev);
466 dev_set_name(f_dev, "%s", dev_name(device));
467 f_dev->parent = device;
468 f_dev->class = &firmware_class;
473 static struct firmware_priv *
474 _request_firmware_prepare(const struct firmware **firmware_p, const char *name,
475 struct device *device, bool uevent, bool nowait)
477 struct firmware *firmware;
478 struct firmware_priv *fw_priv;
481 return ERR_PTR(-EINVAL);
483 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
485 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
487 return ERR_PTR(-ENOMEM);
490 if (fw_get_builtin_firmware(firmware, name)) {
491 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
495 fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
496 if (IS_ERR(fw_priv)) {
497 release_firmware(firmware);
503 static void _request_firmware_cleanup(const struct firmware **firmware_p)
505 release_firmware(*firmware_p);
509 static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
513 struct device *f_dev = &fw_priv->dev;
515 dev_set_uevent_suppress(f_dev, true);
517 /* Need to pin this module until class device is destroyed */
518 __module_get(THIS_MODULE);
520 retval = device_add(f_dev);
522 dev_err(f_dev, "%s: device_register failed\n", __func__);
526 retval = device_create_bin_file(f_dev, &firmware_attr_data);
528 dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
532 retval = device_create_file(f_dev, &dev_attr_loading);
534 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
535 goto err_del_bin_attr;
539 dev_set_uevent_suppress(f_dev, false);
540 dev_dbg(f_dev, "firmware: requesting %s\n", fw_priv->fw_id);
541 if (timeout != MAX_SCHEDULE_TIMEOUT)
542 mod_timer(&fw_priv->timeout,
543 round_jiffies_up(jiffies + timeout));
545 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
548 wait_for_completion(&fw_priv->completion);
550 set_bit(FW_STATUS_DONE, &fw_priv->status);
551 del_timer_sync(&fw_priv->timeout);
553 mutex_lock(&fw_lock);
554 if (!fw_priv->fw->size || test_bit(FW_STATUS_ABORT, &fw_priv->status))
557 mutex_unlock(&fw_lock);
559 device_remove_file(f_dev, &dev_attr_loading);
561 device_remove_bin_file(f_dev, &firmware_attr_data);
570 * request_firmware: - send firmware request and wait for it
571 * @firmware_p: pointer to firmware image
572 * @name: name of firmware file
573 * @device: device for which firmware is being loaded
575 * @firmware_p will be used to return a firmware image by the name
576 * of @name for device @device.
578 * Should be called from user context where sleeping is allowed.
580 * @name will be used as $FIRMWARE in the uevent environment and
581 * should be distinctive enough not to be confused with any other
582 * firmware image for this or any other device.
585 request_firmware(const struct firmware **firmware_p, const char *name,
586 struct device *device)
588 struct firmware_priv *fw_priv;
591 fw_priv = _request_firmware_prepare(firmware_p, name, device, true,
593 if (IS_ERR_OR_NULL(fw_priv))
594 return PTR_RET(fw_priv);
596 ret = usermodehelper_read_trylock();
598 dev_err(device, "firmware: %s will not be loaded\n", name);
600 ret = _request_firmware_load(fw_priv, true,
601 firmware_loading_timeout());
602 usermodehelper_read_unlock();
605 _request_firmware_cleanup(firmware_p);
611 * release_firmware: - release the resource associated with a firmware image
612 * @fw: firmware resource to release
614 void release_firmware(const struct firmware *fw)
617 if (!fw_is_builtin_firmware(fw))
618 firmware_free_data(fw);
624 struct firmware_work {
625 struct work_struct work;
626 struct module *module;
628 struct device *device;
630 void (*cont)(const struct firmware *fw, void *context);
634 static void request_firmware_work_func(struct work_struct *work)
636 struct firmware_work *fw_work;
637 const struct firmware *fw;
638 struct firmware_priv *fw_priv;
642 fw_work = container_of(work, struct firmware_work, work);
643 fw_priv = _request_firmware_prepare(&fw, fw_work->name, fw_work->device,
644 fw_work->uevent, true);
645 if (IS_ERR_OR_NULL(fw_priv)) {
646 ret = PTR_RET(fw_priv);
650 timeout = usermodehelper_read_lock_wait(firmware_loading_timeout());
652 ret = _request_firmware_load(fw_priv, fw_work->uevent, timeout);
653 usermodehelper_read_unlock();
655 dev_dbg(fw_work->device, "firmware: %s loading timed out\n",
660 _request_firmware_cleanup(&fw);
663 fw_work->cont(fw, fw_work->context);
665 module_put(fw_work->module);
670 * request_firmware_nowait - asynchronous version of request_firmware
671 * @module: module requesting the firmware
672 * @uevent: sends uevent to copy the firmware image if this flag
673 * is non-zero else the firmware copy must be done manually.
674 * @name: name of firmware file
675 * @device: device for which firmware is being loaded
676 * @gfp: allocation flags
677 * @context: will be passed over to @cont, and
678 * @fw may be %NULL if firmware request fails.
679 * @cont: function will be called asynchronously when the firmware
682 * Asynchronous variant of request_firmware() for user contexts where
683 * it is not possible to sleep for long time. It can't be called
684 * in atomic contexts.
687 request_firmware_nowait(
688 struct module *module, bool uevent,
689 const char *name, struct device *device, gfp_t gfp, void *context,
690 void (*cont)(const struct firmware *fw, void *context))
692 struct firmware_work *fw_work;
694 fw_work = kzalloc(sizeof (struct firmware_work), gfp);
698 fw_work->module = module;
699 fw_work->name = name;
700 fw_work->device = device;
701 fw_work->context = context;
702 fw_work->cont = cont;
703 fw_work->uevent = uevent;
705 if (!try_module_get(module)) {
710 INIT_WORK(&fw_work->work, request_firmware_work_func);
711 schedule_work(&fw_work->work);
715 static int __init firmware_class_init(void)
717 return class_register(&firmware_class);
720 static void __exit firmware_class_exit(void)
722 class_unregister(&firmware_class);
725 fs_initcall(firmware_class_init);
726 module_exit(firmware_class_exit);
728 EXPORT_SYMBOL(release_firmware);
729 EXPORT_SYMBOL(request_firmware);
730 EXPORT_SYMBOL(request_firmware_nowait);