2 * firmware_class.c - Multi purpose firmware loading support
4 * Copyright (c) 2003 Manuel Estrada Sainz <ranty@debian.org>
6 * Please see Documentation/firmware_class/ for more information.
10 #include <linux/device.h>
11 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/timer.h>
14 #include <linux/vmalloc.h>
15 #include <linux/interrupt.h>
16 #include <linux/bitops.h>
17 #include <asm/semaphore.h>
19 #include <linux/firmware.h>
22 MODULE_AUTHOR("Manuel Estrada Sainz <ranty@debian.org>");
23 MODULE_DESCRIPTION("Multi purpose firmware loading support");
24 MODULE_LICENSE("GPL");
33 static int loading_timeout = 10; /* In seconds */
35 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
36 * guarding for corner cases a global lock should be OK */
37 static DECLARE_MUTEX(fw_lock);
39 struct firmware_priv {
40 char fw_id[FIRMWARE_NAME_MAX];
41 struct completion completion;
42 struct bin_attribute attr_data;
46 struct timer_list timeout;
50 fw_load_abort(struct firmware_priv *fw_priv)
52 set_bit(FW_STATUS_ABORT, &fw_priv->status);
54 complete(&fw_priv->completion);
58 firmware_timeout_show(struct class *class, char *buf)
60 return sprintf(buf, "%d\n", loading_timeout);
64 * firmware_timeout_store:
66 * Sets the number of seconds to wait for the firmware. Once
67 * this expires an error will be return to the driver and no
68 * firmware will be provided.
70 * Note: zero means 'wait for ever'
74 firmware_timeout_store(struct class *class, const char *buf, size_t count)
76 loading_timeout = simple_strtol(buf, NULL, 10);
80 static CLASS_ATTR(timeout, 0644, firmware_timeout_show, firmware_timeout_store);
82 static void fw_class_dev_release(struct class_device *class_dev);
83 int firmware_class_hotplug(struct class_device *dev, char **envp,
84 int num_envp, char *buffer, int buffer_size);
86 static struct class firmware_class = {
88 .hotplug = firmware_class_hotplug,
89 .release = fw_class_dev_release,
93 firmware_class_hotplug(struct class_device *class_dev, char **envp,
94 int num_envp, char *buffer, int buffer_size)
96 struct firmware_priv *fw_priv = class_get_devdata(class_dev);
98 char *scratch = buffer;
100 if (!test_bit(FW_STATUS_READY, &fw_priv->status))
103 if (buffer_size < (FIRMWARE_NAME_MAX + 10))
109 scratch += sprintf(scratch, "FIRMWARE=%s", fw_priv->fw_id) + 1;
114 firmware_loading_show(struct class_device *class_dev, char *buf)
116 struct firmware_priv *fw_priv = class_get_devdata(class_dev);
117 int loading = test_bit(FW_STATUS_LOADING, &fw_priv->status);
118 return sprintf(buf, "%d\n", loading);
122 * firmware_loading_store: - loading control file
124 * The relevant values are:
126 * 1: Start a load, discarding any previous partial load.
127 * 0: Conclude the load and handle the data to the driver code.
128 * -1: Conclude the load with an error and discard any written data.
131 firmware_loading_store(struct class_device *class_dev,
132 const char *buf, size_t count)
134 struct firmware_priv *fw_priv = class_get_devdata(class_dev);
135 int loading = simple_strtol(buf, NULL, 10);
140 vfree(fw_priv->fw->data);
141 fw_priv->fw->data = NULL;
142 fw_priv->fw->size = 0;
143 fw_priv->alloc_size = 0;
144 set_bit(FW_STATUS_LOADING, &fw_priv->status);
148 if (test_bit(FW_STATUS_LOADING, &fw_priv->status)) {
149 complete(&fw_priv->completion);
150 clear_bit(FW_STATUS_LOADING, &fw_priv->status);
155 printk(KERN_ERR "%s: unexpected value (%d)\n", __FUNCTION__,
159 fw_load_abort(fw_priv);
166 static CLASS_DEVICE_ATTR(loading, 0644,
167 firmware_loading_show, firmware_loading_store);
170 firmware_data_read(struct kobject *kobj,
171 char *buffer, loff_t offset, size_t count)
173 struct class_device *class_dev = to_class_dev(kobj);
174 struct firmware_priv *fw_priv = class_get_devdata(class_dev);
176 ssize_t ret_count = count;
180 if (test_bit(FW_STATUS_DONE, &fw_priv->status)) {
184 if (offset > fw->size) {
188 if (offset + ret_count > fw->size)
189 ret_count = fw->size - offset;
191 memcpy(buffer, fw->data + offset, ret_count);
197 fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
201 if (min_size <= fw_priv->alloc_size)
204 new_data = vmalloc(fw_priv->alloc_size + PAGE_SIZE);
206 printk(KERN_ERR "%s: unable to alloc buffer\n", __FUNCTION__);
207 /* Make sure that we don't keep incomplete data */
208 fw_load_abort(fw_priv);
211 fw_priv->alloc_size += PAGE_SIZE;
212 if (fw_priv->fw->data) {
213 memcpy(new_data, fw_priv->fw->data, fw_priv->fw->size);
214 vfree(fw_priv->fw->data);
216 fw_priv->fw->data = new_data;
217 BUG_ON(min_size > fw_priv->alloc_size);
222 * firmware_data_write:
226 * Data written to the 'data' attribute will be later handled to
227 * the driver as a firmware image.
230 firmware_data_write(struct kobject *kobj,
231 char *buffer, loff_t offset, size_t count)
233 struct class_device *class_dev = to_class_dev(kobj);
234 struct firmware_priv *fw_priv = class_get_devdata(class_dev);
238 if (!capable(CAP_SYS_RAWIO))
242 if (test_bit(FW_STATUS_DONE, &fw_priv->status)) {
246 retval = fw_realloc_buffer(fw_priv, offset + count);
250 memcpy(fw->data + offset, buffer, count);
252 fw->size = max_t(size_t, offset + count, fw->size);
258 static struct bin_attribute firmware_attr_data_tmpl = {
259 .attr = {.name = "data", .mode = 0644, .owner = THIS_MODULE},
261 .read = firmware_data_read,
262 .write = firmware_data_write,
266 fw_class_dev_release(struct class_device *class_dev)
268 struct firmware_priv *fw_priv = class_get_devdata(class_dev);
273 module_put(THIS_MODULE);
277 firmware_class_timeout(u_long data)
279 struct firmware_priv *fw_priv = (struct firmware_priv *) data;
280 fw_load_abort(fw_priv);
284 fw_setup_class_device_id(struct class_device *class_dev, struct device *dev)
286 /* XXX warning we should watch out for name collisions */
287 strlcpy(class_dev->class_id, dev->bus_id, BUS_ID_SIZE);
291 fw_register_class_device(struct class_device **class_dev_p,
292 const char *fw_name, struct device *device)
295 struct firmware_priv *fw_priv = kmalloc(sizeof (struct firmware_priv),
297 struct class_device *class_dev = kmalloc(sizeof (struct class_device),
302 if (!fw_priv || !class_dev) {
303 printk(KERN_ERR "%s: kmalloc failed\n", __FUNCTION__);
307 memset(fw_priv, 0, sizeof (*fw_priv));
308 memset(class_dev, 0, sizeof (*class_dev));
310 init_completion(&fw_priv->completion);
311 fw_priv->attr_data = firmware_attr_data_tmpl;
312 strlcpy(fw_priv->fw_id, fw_name, FIRMWARE_NAME_MAX);
314 fw_priv->timeout.function = firmware_class_timeout;
315 fw_priv->timeout.data = (u_long) fw_priv;
316 init_timer(&fw_priv->timeout);
318 fw_setup_class_device_id(class_dev, device);
319 class_dev->dev = device;
320 class_dev->class = &firmware_class;
321 class_set_devdata(class_dev, fw_priv);
322 retval = class_device_register(class_dev);
324 printk(KERN_ERR "%s: class_device_register failed\n",
328 *class_dev_p = class_dev;
338 fw_setup_class_device(struct firmware *fw, struct class_device **class_dev_p,
339 const char *fw_name, struct device *device)
341 struct class_device *class_dev;
342 struct firmware_priv *fw_priv;
346 retval = fw_register_class_device(&class_dev, fw_name, device);
350 /* Need to pin this module until class device is destroyed */
351 __module_get(THIS_MODULE);
353 fw_priv = class_get_devdata(class_dev);
356 retval = sysfs_create_bin_file(&class_dev->kobj, &fw_priv->attr_data);
358 printk(KERN_ERR "%s: sysfs_create_bin_file failed\n",
363 retval = class_device_create_file(class_dev,
364 &class_device_attr_loading);
366 printk(KERN_ERR "%s: class_device_create_file failed\n",
371 set_bit(FW_STATUS_READY, &fw_priv->status);
372 *class_dev_p = class_dev;
376 class_device_unregister(class_dev);
382 * request_firmware: - request firmware to hotplug and wait for it
384 * @firmware will be used to return a firmware image by the name
385 * of @name for device @device.
387 * Should be called from user context where sleeping is allowed.
389 * @name will be use as $FIRMWARE in the hotplug environment and
390 * should be distinctive enough not to be confused with any other
391 * firmware image for this or any other device.
394 request_firmware(const struct firmware **firmware_p, const char *name,
395 struct device *device)
397 struct class_device *class_dev;
398 struct firmware_priv *fw_priv;
399 struct firmware *firmware;
405 *firmware_p = firmware = kmalloc(sizeof (struct firmware), GFP_KERNEL);
407 printk(KERN_ERR "%s: kmalloc(struct firmware) failed\n",
412 memset(firmware, 0, sizeof (*firmware));
414 retval = fw_setup_class_device(firmware, &class_dev, name, device);
418 fw_priv = class_get_devdata(class_dev);
420 if (loading_timeout) {
421 fw_priv->timeout.expires = jiffies + loading_timeout * HZ;
422 add_timer(&fw_priv->timeout);
425 kobject_hotplug("add", &class_dev->kobj);
426 wait_for_completion(&fw_priv->completion);
427 set_bit(FW_STATUS_DONE, &fw_priv->status);
429 del_timer_sync(&fw_priv->timeout);
432 if (!fw_priv->fw->size || test_bit(FW_STATUS_ABORT, &fw_priv->status)) {
434 release_firmware(fw_priv->fw);
439 class_device_unregister(class_dev);
449 * release_firmware: - release the resource associated with a firmware image
452 release_firmware(const struct firmware *fw)
461 * register_firmware: - provide a firmware image for later usage
464 * Make sure that @data will be available by requesting firmware @name.
466 * Note: This will not be possible until some kind of persistence
470 register_firmware(const char *name, const u8 *data, size_t size)
472 /* This is meaningless without firmware caching, so until we
473 * decide if firmware caching is reasonable just leave it as a
478 struct firmware_work {
479 struct work_struct work;
480 struct module *module;
482 struct device *device;
484 void (*cont)(const struct firmware *fw, void *context);
488 request_firmware_work_func(void *arg)
490 struct firmware_work *fw_work = arg;
491 const struct firmware *fw;
496 daemonize("%s/%s", "firmware", fw_work->name);
497 request_firmware(&fw, fw_work->name, fw_work->device);
498 fw_work->cont(fw, fw_work->context);
499 release_firmware(fw);
500 module_put(fw_work->module);
506 * request_firmware_nowait:
509 * Asynchronous variant of request_firmware() for contexts where
510 * it is not possible to sleep.
512 * @cont will be called asynchronously when the firmware request is over.
514 * @context will be passed over to @cont.
516 * @fw may be %NULL if firmware request fails.
520 request_firmware_nowait(
521 struct module *module,
522 const char *name, struct device *device, void *context,
523 void (*cont)(const struct firmware *fw, void *context))
525 struct firmware_work *fw_work = kmalloc(sizeof (struct firmware_work),
531 if (!try_module_get(module)) {
536 *fw_work = (struct firmware_work) {
544 ret = kernel_thread(request_firmware_work_func, fw_work,
545 CLONE_FS | CLONE_FILES);
548 fw_work->cont(NULL, fw_work->context);
555 firmware_class_init(void)
558 error = class_register(&firmware_class);
560 printk(KERN_ERR "%s: class_register failed\n", __FUNCTION__);
563 error = class_create_file(&firmware_class, &class_attr_timeout);
565 printk(KERN_ERR "%s: class_create_file failed\n",
567 class_unregister(&firmware_class);
573 firmware_class_exit(void)
575 class_unregister(&firmware_class);
578 module_init(firmware_class_init);
579 module_exit(firmware_class_exit);
581 EXPORT_SYMBOL(release_firmware);
582 EXPORT_SYMBOL(request_firmware);
583 EXPORT_SYMBOL(request_firmware_nowait);
584 EXPORT_SYMBOL(register_firmware);
585 EXPORT_SYMBOL(firmware_class);