diff options
Diffstat (limited to 'drivers/base/firmware_class.c')
-rw-r--r-- | drivers/base/firmware_class.c | 583 |
1 files changed, 583 insertions, 0 deletions
diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c new file mode 100644 index 000000000000..26c9464af80a --- /dev/null +++ b/drivers/base/firmware_class.c | |||
@@ -0,0 +1,583 @@ | |||
1 | /* | ||
2 | * firmware_class.c - Multi purpose firmware loading support | ||
3 | * | ||
4 | * Copyright (c) 2003 Manuel Estrada Sainz <ranty@debian.org> | ||
5 | * | ||
6 | * Please see Documentation/firmware_class/ for more information. | ||
7 | * | ||
8 | */ | ||
9 | |||
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> | ||
18 | |||
19 | #include <linux/firmware.h> | ||
20 | #include "base.h" | ||
21 | |||
22 | MODULE_AUTHOR("Manuel Estrada Sainz <ranty@debian.org>"); | ||
23 | MODULE_DESCRIPTION("Multi purpose firmware loading support"); | ||
24 | MODULE_LICENSE("GPL"); | ||
25 | |||
26 | enum { | ||
27 | FW_STATUS_LOADING, | ||
28 | FW_STATUS_DONE, | ||
29 | FW_STATUS_ABORT, | ||
30 | FW_STATUS_READY, | ||
31 | }; | ||
32 | |||
33 | static int loading_timeout = 10; /* In seconds */ | ||
34 | |||
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); | ||
38 | |||
39 | struct firmware_priv { | ||
40 | char fw_id[FIRMWARE_NAME_MAX]; | ||
41 | struct completion completion; | ||
42 | struct bin_attribute attr_data; | ||
43 | struct firmware *fw; | ||
44 | unsigned long status; | ||
45 | int alloc_size; | ||
46 | struct timer_list timeout; | ||
47 | }; | ||
48 | |||
49 | static inline void | ||
50 | fw_load_abort(struct firmware_priv *fw_priv) | ||
51 | { | ||
52 | set_bit(FW_STATUS_ABORT, &fw_priv->status); | ||
53 | wmb(); | ||
54 | complete(&fw_priv->completion); | ||
55 | } | ||
56 | |||
57 | static ssize_t | ||
58 | firmware_timeout_show(struct class *class, char *buf) | ||
59 | { | ||
60 | return sprintf(buf, "%d\n", loading_timeout); | ||
61 | } | ||
62 | |||
63 | /** | ||
64 | * firmware_timeout_store: | ||
65 | * Description: | ||
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. | ||
69 | * | ||
70 | * Note: zero means 'wait for ever' | ||
71 | * | ||
72 | **/ | ||
73 | static ssize_t | ||
74 | firmware_timeout_store(struct class *class, const char *buf, size_t count) | ||
75 | { | ||
76 | loading_timeout = simple_strtol(buf, NULL, 10); | ||
77 | return count; | ||
78 | } | ||
79 | |||
80 | static CLASS_ATTR(timeout, 0644, firmware_timeout_show, firmware_timeout_store); | ||
81 | |||
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); | ||
85 | |||
86 | static struct class firmware_class = { | ||
87 | .name = "firmware", | ||
88 | .hotplug = firmware_class_hotplug, | ||
89 | .release = fw_class_dev_release, | ||
90 | }; | ||
91 | |||
92 | int | ||
93 | firmware_class_hotplug(struct class_device *class_dev, char **envp, | ||
94 | int num_envp, char *buffer, int buffer_size) | ||
95 | { | ||
96 | struct firmware_priv *fw_priv = class_get_devdata(class_dev); | ||
97 | int i = 0, len = 0; | ||
98 | |||
99 | if (!test_bit(FW_STATUS_READY, &fw_priv->status)) | ||
100 | return -ENODEV; | ||
101 | |||
102 | if (add_hotplug_env_var(envp, num_envp, &i, buffer, buffer_size, &len, | ||
103 | "FIRMWARE=%s", fw_priv->fw_id)) | ||
104 | return -ENOMEM; | ||
105 | |||
106 | envp[i] = NULL; | ||
107 | |||
108 | return 0; | ||
109 | } | ||
110 | |||
111 | static ssize_t | ||
112 | firmware_loading_show(struct class_device *class_dev, char *buf) | ||
113 | { | ||
114 | struct firmware_priv *fw_priv = class_get_devdata(class_dev); | ||
115 | int loading = test_bit(FW_STATUS_LOADING, &fw_priv->status); | ||
116 | return sprintf(buf, "%d\n", loading); | ||
117 | } | ||
118 | |||
119 | /** | ||
120 | * firmware_loading_store: - loading control file | ||
121 | * Description: | ||
122 | * The relevant values are: | ||
123 | * | ||
124 | * 1: Start a load, discarding any previous partial load. | ||
125 | * 0: Conclude the load and handle the data to the driver code. | ||
126 | * -1: Conclude the load with an error and discard any written data. | ||
127 | **/ | ||
128 | static ssize_t | ||
129 | firmware_loading_store(struct class_device *class_dev, | ||
130 | const char *buf, size_t count) | ||
131 | { | ||
132 | struct firmware_priv *fw_priv = class_get_devdata(class_dev); | ||
133 | int loading = simple_strtol(buf, NULL, 10); | ||
134 | |||
135 | switch (loading) { | ||
136 | case 1: | ||
137 | down(&fw_lock); | ||
138 | vfree(fw_priv->fw->data); | ||
139 | fw_priv->fw->data = NULL; | ||
140 | fw_priv->fw->size = 0; | ||
141 | fw_priv->alloc_size = 0; | ||
142 | set_bit(FW_STATUS_LOADING, &fw_priv->status); | ||
143 | up(&fw_lock); | ||
144 | break; | ||
145 | case 0: | ||
146 | if (test_bit(FW_STATUS_LOADING, &fw_priv->status)) { | ||
147 | complete(&fw_priv->completion); | ||
148 | clear_bit(FW_STATUS_LOADING, &fw_priv->status); | ||
149 | break; | ||
150 | } | ||
151 | /* fallthrough */ | ||
152 | default: | ||
153 | printk(KERN_ERR "%s: unexpected value (%d)\n", __FUNCTION__, | ||
154 | loading); | ||
155 | /* fallthrough */ | ||
156 | case -1: | ||
157 | fw_load_abort(fw_priv); | ||
158 | break; | ||
159 | } | ||
160 | |||
161 | return count; | ||
162 | } | ||
163 | |||
164 | static CLASS_DEVICE_ATTR(loading, 0644, | ||
165 | firmware_loading_show, firmware_loading_store); | ||
166 | |||
167 | static ssize_t | ||
168 | firmware_data_read(struct kobject *kobj, | ||
169 | char *buffer, loff_t offset, size_t count) | ||
170 | { | ||
171 | struct class_device *class_dev = to_class_dev(kobj); | ||
172 | struct firmware_priv *fw_priv = class_get_devdata(class_dev); | ||
173 | struct firmware *fw; | ||
174 | ssize_t ret_count = count; | ||
175 | |||
176 | down(&fw_lock); | ||
177 | fw = fw_priv->fw; | ||
178 | if (test_bit(FW_STATUS_DONE, &fw_priv->status)) { | ||
179 | ret_count = -ENODEV; | ||
180 | goto out; | ||
181 | } | ||
182 | if (offset > fw->size) { | ||
183 | ret_count = 0; | ||
184 | goto out; | ||
185 | } | ||
186 | if (offset + ret_count > fw->size) | ||
187 | ret_count = fw->size - offset; | ||
188 | |||
189 | memcpy(buffer, fw->data + offset, ret_count); | ||
190 | out: | ||
191 | up(&fw_lock); | ||
192 | return ret_count; | ||
193 | } | ||
194 | static int | ||
195 | fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size) | ||
196 | { | ||
197 | u8 *new_data; | ||
198 | |||
199 | if (min_size <= fw_priv->alloc_size) | ||
200 | return 0; | ||
201 | |||
202 | new_data = vmalloc(fw_priv->alloc_size + PAGE_SIZE); | ||
203 | if (!new_data) { | ||
204 | printk(KERN_ERR "%s: unable to alloc buffer\n", __FUNCTION__); | ||
205 | /* Make sure that we don't keep incomplete data */ | ||
206 | fw_load_abort(fw_priv); | ||
207 | return -ENOMEM; | ||
208 | } | ||
209 | fw_priv->alloc_size += PAGE_SIZE; | ||
210 | if (fw_priv->fw->data) { | ||
211 | memcpy(new_data, fw_priv->fw->data, fw_priv->fw->size); | ||
212 | vfree(fw_priv->fw->data); | ||
213 | } | ||
214 | fw_priv->fw->data = new_data; | ||
215 | BUG_ON(min_size > fw_priv->alloc_size); | ||
216 | return 0; | ||
217 | } | ||
218 | |||
219 | /** | ||
220 | * firmware_data_write: | ||
221 | * | ||
222 | * Description: | ||
223 | * | ||
224 | * Data written to the 'data' attribute will be later handled to | ||
225 | * the driver as a firmware image. | ||
226 | **/ | ||
227 | static ssize_t | ||
228 | firmware_data_write(struct kobject *kobj, | ||
229 | char *buffer, loff_t offset, size_t count) | ||
230 | { | ||
231 | struct class_device *class_dev = to_class_dev(kobj); | ||
232 | struct firmware_priv *fw_priv = class_get_devdata(class_dev); | ||
233 | struct firmware *fw; | ||
234 | ssize_t retval; | ||
235 | |||
236 | if (!capable(CAP_SYS_RAWIO)) | ||
237 | return -EPERM; | ||
238 | down(&fw_lock); | ||
239 | fw = fw_priv->fw; | ||
240 | if (test_bit(FW_STATUS_DONE, &fw_priv->status)) { | ||
241 | retval = -ENODEV; | ||
242 | goto out; | ||
243 | } | ||
244 | retval = fw_realloc_buffer(fw_priv, offset + count); | ||
245 | if (retval) | ||
246 | goto out; | ||
247 | |||
248 | memcpy(fw->data + offset, buffer, count); | ||
249 | |||
250 | fw->size = max_t(size_t, offset + count, fw->size); | ||
251 | retval = count; | ||
252 | out: | ||
253 | up(&fw_lock); | ||
254 | return retval; | ||
255 | } | ||
256 | static struct bin_attribute firmware_attr_data_tmpl = { | ||
257 | .attr = {.name = "data", .mode = 0644, .owner = THIS_MODULE}, | ||
258 | .size = 0, | ||
259 | .read = firmware_data_read, | ||
260 | .write = firmware_data_write, | ||
261 | }; | ||
262 | |||
263 | static void | ||
264 | fw_class_dev_release(struct class_device *class_dev) | ||
265 | { | ||
266 | struct firmware_priv *fw_priv = class_get_devdata(class_dev); | ||
267 | |||
268 | kfree(fw_priv); | ||
269 | kfree(class_dev); | ||
270 | |||
271 | module_put(THIS_MODULE); | ||
272 | } | ||
273 | |||
274 | static void | ||
275 | firmware_class_timeout(u_long data) | ||
276 | { | ||
277 | struct firmware_priv *fw_priv = (struct firmware_priv *) data; | ||
278 | fw_load_abort(fw_priv); | ||
279 | } | ||
280 | |||
281 | static inline void | ||
282 | fw_setup_class_device_id(struct class_device *class_dev, struct device *dev) | ||
283 | { | ||
284 | /* XXX warning we should watch out for name collisions */ | ||
285 | strlcpy(class_dev->class_id, dev->bus_id, BUS_ID_SIZE); | ||
286 | } | ||
287 | |||
288 | static int | ||
289 | fw_register_class_device(struct class_device **class_dev_p, | ||
290 | const char *fw_name, struct device *device) | ||
291 | { | ||
292 | int retval; | ||
293 | struct firmware_priv *fw_priv = kmalloc(sizeof (struct firmware_priv), | ||
294 | GFP_KERNEL); | ||
295 | struct class_device *class_dev = kmalloc(sizeof (struct class_device), | ||
296 | GFP_KERNEL); | ||
297 | |||
298 | *class_dev_p = NULL; | ||
299 | |||
300 | if (!fw_priv || !class_dev) { | ||
301 | printk(KERN_ERR "%s: kmalloc failed\n", __FUNCTION__); | ||
302 | retval = -ENOMEM; | ||
303 | goto error_kfree; | ||
304 | } | ||
305 | memset(fw_priv, 0, sizeof (*fw_priv)); | ||
306 | memset(class_dev, 0, sizeof (*class_dev)); | ||
307 | |||
308 | init_completion(&fw_priv->completion); | ||
309 | fw_priv->attr_data = firmware_attr_data_tmpl; | ||
310 | strlcpy(fw_priv->fw_id, fw_name, FIRMWARE_NAME_MAX); | ||
311 | |||
312 | fw_priv->timeout.function = firmware_class_timeout; | ||
313 | fw_priv->timeout.data = (u_long) fw_priv; | ||
314 | init_timer(&fw_priv->timeout); | ||
315 | |||
316 | fw_setup_class_device_id(class_dev, device); | ||
317 | class_dev->dev = device; | ||
318 | class_dev->class = &firmware_class; | ||
319 | class_set_devdata(class_dev, fw_priv); | ||
320 | retval = class_device_register(class_dev); | ||
321 | if (retval) { | ||
322 | printk(KERN_ERR "%s: class_device_register failed\n", | ||
323 | __FUNCTION__); | ||
324 | goto error_kfree; | ||
325 | } | ||
326 | *class_dev_p = class_dev; | ||
327 | return 0; | ||
328 | |||
329 | error_kfree: | ||
330 | kfree(fw_priv); | ||
331 | kfree(class_dev); | ||
332 | return retval; | ||
333 | } | ||
334 | |||
335 | static int | ||
336 | fw_setup_class_device(struct firmware *fw, struct class_device **class_dev_p, | ||
337 | const char *fw_name, struct device *device) | ||
338 | { | ||
339 | struct class_device *class_dev; | ||
340 | struct firmware_priv *fw_priv; | ||
341 | int retval; | ||
342 | |||
343 | *class_dev_p = NULL; | ||
344 | retval = fw_register_class_device(&class_dev, fw_name, device); | ||
345 | if (retval) | ||
346 | goto out; | ||
347 | |||
348 | /* Need to pin this module until class device is destroyed */ | ||
349 | __module_get(THIS_MODULE); | ||
350 | |||
351 | fw_priv = class_get_devdata(class_dev); | ||
352 | |||
353 | fw_priv->fw = fw; | ||
354 | retval = sysfs_create_bin_file(&class_dev->kobj, &fw_priv->attr_data); | ||
355 | if (retval) { | ||
356 | printk(KERN_ERR "%s: sysfs_create_bin_file failed\n", | ||
357 | __FUNCTION__); | ||
358 | goto error_unreg; | ||
359 | } | ||
360 | |||
361 | retval = class_device_create_file(class_dev, | ||
362 | &class_device_attr_loading); | ||
363 | if (retval) { | ||
364 | printk(KERN_ERR "%s: class_device_create_file failed\n", | ||
365 | __FUNCTION__); | ||
366 | goto error_unreg; | ||
367 | } | ||
368 | |||
369 | set_bit(FW_STATUS_READY, &fw_priv->status); | ||
370 | *class_dev_p = class_dev; | ||
371 | goto out; | ||
372 | |||
373 | error_unreg: | ||
374 | class_device_unregister(class_dev); | ||
375 | out: | ||
376 | return retval; | ||
377 | } | ||
378 | |||
379 | /** | ||
380 | * request_firmware: - request firmware to hotplug and wait for it | ||
381 | * Description: | ||
382 | * @firmware will be used to return a firmware image by the name | ||
383 | * of @name for device @device. | ||
384 | * | ||
385 | * Should be called from user context where sleeping is allowed. | ||
386 | * | ||
387 | * @name will be use as $FIRMWARE in the hotplug environment and | ||
388 | * should be distinctive enough not to be confused with any other | ||
389 | * firmware image for this or any other device. | ||
390 | **/ | ||
391 | int | ||
392 | request_firmware(const struct firmware **firmware_p, const char *name, | ||
393 | struct device *device) | ||
394 | { | ||
395 | struct class_device *class_dev; | ||
396 | struct firmware_priv *fw_priv; | ||
397 | struct firmware *firmware; | ||
398 | int retval; | ||
399 | |||
400 | if (!firmware_p) | ||
401 | return -EINVAL; | ||
402 | |||
403 | *firmware_p = firmware = kmalloc(sizeof (struct firmware), GFP_KERNEL); | ||
404 | if (!firmware) { | ||
405 | printk(KERN_ERR "%s: kmalloc(struct firmware) failed\n", | ||
406 | __FUNCTION__); | ||
407 | retval = -ENOMEM; | ||
408 | goto out; | ||
409 | } | ||
410 | memset(firmware, 0, sizeof (*firmware)); | ||
411 | |||
412 | retval = fw_setup_class_device(firmware, &class_dev, name, device); | ||
413 | if (retval) | ||
414 | goto error_kfree_fw; | ||
415 | |||
416 | fw_priv = class_get_devdata(class_dev); | ||
417 | |||
418 | if (loading_timeout) { | ||
419 | fw_priv->timeout.expires = jiffies + loading_timeout * HZ; | ||
420 | add_timer(&fw_priv->timeout); | ||
421 | } | ||
422 | |||
423 | kobject_hotplug(&class_dev->kobj, KOBJ_ADD); | ||
424 | wait_for_completion(&fw_priv->completion); | ||
425 | set_bit(FW_STATUS_DONE, &fw_priv->status); | ||
426 | |||
427 | del_timer_sync(&fw_priv->timeout); | ||
428 | |||
429 | down(&fw_lock); | ||
430 | if (!fw_priv->fw->size || test_bit(FW_STATUS_ABORT, &fw_priv->status)) { | ||
431 | retval = -ENOENT; | ||
432 | release_firmware(fw_priv->fw); | ||
433 | *firmware_p = NULL; | ||
434 | } | ||
435 | fw_priv->fw = NULL; | ||
436 | up(&fw_lock); | ||
437 | class_device_unregister(class_dev); | ||
438 | goto out; | ||
439 | |||
440 | error_kfree_fw: | ||
441 | kfree(firmware); | ||
442 | *firmware_p = NULL; | ||
443 | out: | ||
444 | return retval; | ||
445 | } | ||
446 | |||
447 | /** | ||
448 | * release_firmware: - release the resource associated with a firmware image | ||
449 | **/ | ||
450 | void | ||
451 | release_firmware(const struct firmware *fw) | ||
452 | { | ||
453 | if (fw) { | ||
454 | vfree(fw->data); | ||
455 | kfree(fw); | ||
456 | } | ||
457 | } | ||
458 | |||
459 | /** | ||
460 | * register_firmware: - provide a firmware image for later usage | ||
461 | * | ||
462 | * Description: | ||
463 | * Make sure that @data will be available by requesting firmware @name. | ||
464 | * | ||
465 | * Note: This will not be possible until some kind of persistence | ||
466 | * is available. | ||
467 | **/ | ||
468 | void | ||
469 | register_firmware(const char *name, const u8 *data, size_t size) | ||
470 | { | ||
471 | /* This is meaningless without firmware caching, so until we | ||
472 | * decide if firmware caching is reasonable just leave it as a | ||
473 | * noop */ | ||
474 | } | ||
475 | |||
476 | /* Async support */ | ||
477 | struct firmware_work { | ||
478 | struct work_struct work; | ||
479 | struct module *module; | ||
480 | const char *name; | ||
481 | struct device *device; | ||
482 | void *context; | ||
483 | void (*cont)(const struct firmware *fw, void *context); | ||
484 | }; | ||
485 | |||
486 | static int | ||
487 | request_firmware_work_func(void *arg) | ||
488 | { | ||
489 | struct firmware_work *fw_work = arg; | ||
490 | const struct firmware *fw; | ||
491 | if (!arg) { | ||
492 | WARN_ON(1); | ||
493 | return 0; | ||
494 | } | ||
495 | daemonize("%s/%s", "firmware", fw_work->name); | ||
496 | request_firmware(&fw, fw_work->name, fw_work->device); | ||
497 | fw_work->cont(fw, fw_work->context); | ||
498 | release_firmware(fw); | ||
499 | module_put(fw_work->module); | ||
500 | kfree(fw_work); | ||
501 | return 0; | ||
502 | } | ||
503 | |||
504 | /** | ||
505 | * request_firmware_nowait: | ||
506 | * | ||
507 | * Description: | ||
508 | * Asynchronous variant of request_firmware() for contexts where | ||
509 | * it is not possible to sleep. | ||
510 | * | ||
511 | * @cont will be called asynchronously when the firmware request is over. | ||
512 | * | ||
513 | * @context will be passed over to @cont. | ||
514 | * | ||
515 | * @fw may be %NULL if firmware request fails. | ||
516 | * | ||
517 | **/ | ||
518 | int | ||
519 | request_firmware_nowait( | ||
520 | struct module *module, | ||
521 | const char *name, struct device *device, void *context, | ||
522 | void (*cont)(const struct firmware *fw, void *context)) | ||
523 | { | ||
524 | struct firmware_work *fw_work = kmalloc(sizeof (struct firmware_work), | ||
525 | GFP_ATOMIC); | ||
526 | int ret; | ||
527 | |||
528 | if (!fw_work) | ||
529 | return -ENOMEM; | ||
530 | if (!try_module_get(module)) { | ||
531 | kfree(fw_work); | ||
532 | return -EFAULT; | ||
533 | } | ||
534 | |||
535 | *fw_work = (struct firmware_work) { | ||
536 | .module = module, | ||
537 | .name = name, | ||
538 | .device = device, | ||
539 | .context = context, | ||
540 | .cont = cont, | ||
541 | }; | ||
542 | |||
543 | ret = kernel_thread(request_firmware_work_func, fw_work, | ||
544 | CLONE_FS | CLONE_FILES); | ||
545 | |||
546 | if (ret < 0) { | ||
547 | fw_work->cont(NULL, fw_work->context); | ||
548 | return ret; | ||
549 | } | ||
550 | return 0; | ||
551 | } | ||
552 | |||
553 | static int __init | ||
554 | firmware_class_init(void) | ||
555 | { | ||
556 | int error; | ||
557 | error = class_register(&firmware_class); | ||
558 | if (error) { | ||
559 | printk(KERN_ERR "%s: class_register failed\n", __FUNCTION__); | ||
560 | return error; | ||
561 | } | ||
562 | error = class_create_file(&firmware_class, &class_attr_timeout); | ||
563 | if (error) { | ||
564 | printk(KERN_ERR "%s: class_create_file failed\n", | ||
565 | __FUNCTION__); | ||
566 | class_unregister(&firmware_class); | ||
567 | } | ||
568 | return error; | ||
569 | |||
570 | } | ||
571 | static void __exit | ||
572 | firmware_class_exit(void) | ||
573 | { | ||
574 | class_unregister(&firmware_class); | ||
575 | } | ||
576 | |||
577 | module_init(firmware_class_init); | ||
578 | module_exit(firmware_class_exit); | ||
579 | |||
580 | EXPORT_SYMBOL(release_firmware); | ||
581 | EXPORT_SYMBOL(request_firmware); | ||
582 | EXPORT_SYMBOL(request_firmware_nowait); | ||
583 | EXPORT_SYMBOL(register_firmware); | ||