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989d42e8 | 1 | // SPDX-License-Identifier: GPL-2.0 |
07e4a3e2 | 2 | /* |
4a3ad20c | 3 | * drivers/base/dd.c - The core device/driver interactions. |
07e4a3e2 | 4 | * |
4a3ad20c GKH |
5 | * This file contains the (sometimes tricky) code that controls the |
6 | * interactions between devices and drivers, which primarily includes | |
7 | * driver binding and unbinding. | |
07e4a3e2 | 8 | * |
4a3ad20c GKH |
9 | * All of this code used to exist in drivers/base/bus.c, but was |
10 | * relocated to here in the name of compartmentalization (since it wasn't | |
11 | * strictly code just for the 'struct bus_type'. | |
07e4a3e2 | 12 | * |
4a3ad20c GKH |
13 | * Copyright (c) 2002-5 Patrick Mochel |
14 | * Copyright (c) 2002-3 Open Source Development Labs | |
b4028437 GKH |
15 | * Copyright (c) 2007-2009 Greg Kroah-Hartman <gregkh@suse.de> |
16 | * Copyright (c) 2007-2009 Novell Inc. | |
07e4a3e2 PM |
17 | */ |
18 | ||
28af109a | 19 | #include <linux/debugfs.h> |
07e4a3e2 | 20 | #include <linux/device.h> |
216773a7 | 21 | #include <linux/delay.h> |
09515ef5 | 22 | #include <linux/dma-mapping.h> |
1f5000bd | 23 | #include <linux/init.h> |
07e4a3e2 | 24 | #include <linux/module.h> |
d779249e | 25 | #include <linux/kthread.h> |
735a7ffb | 26 | #include <linux/wait.h> |
216773a7 | 27 | #include <linux/async.h> |
5e928f77 | 28 | #include <linux/pm_runtime.h> |
ab78029e | 29 | #include <linux/pinctrl/devinfo.h> |
07e4a3e2 PM |
30 | |
31 | #include "base.h" | |
32 | #include "power/power.h" | |
33 | ||
d1c3414c GL |
34 | /* |
35 | * Deferred Probe infrastructure. | |
36 | * | |
37 | * Sometimes driver probe order matters, but the kernel doesn't always have | |
38 | * dependency information which means some drivers will get probed before a | |
39 | * resource it depends on is available. For example, an SDHCI driver may | |
40 | * first need a GPIO line from an i2c GPIO controller before it can be | |
41 | * initialized. If a required resource is not available yet, a driver can | |
42 | * request probing to be deferred by returning -EPROBE_DEFER from its probe hook | |
43 | * | |
44 | * Deferred probe maintains two lists of devices, a pending list and an active | |
45 | * list. A driver returning -EPROBE_DEFER causes the device to be added to the | |
46 | * pending list. A successful driver probe will trigger moving all devices | |
47 | * from the pending to the active list so that the workqueue will eventually | |
48 | * retry them. | |
49 | * | |
50 | * The deferred_probe_mutex must be held any time the deferred_probe_*_list | |
ef8a3fd6 | 51 | * of the (struct device*)->p->deferred_probe pointers are manipulated |
d1c3414c GL |
52 | */ |
53 | static DEFINE_MUTEX(deferred_probe_mutex); | |
54 | static LIST_HEAD(deferred_probe_pending_list); | |
55 | static LIST_HEAD(deferred_probe_active_list); | |
58b116bc | 56 | static atomic_t deferred_trigger_count = ATOMIC_INIT(0); |
28af109a | 57 | static struct dentry *deferred_devices; |
25b4e70d | 58 | static bool initcalls_done; |
d1c3414c | 59 | |
1ea61b68 FT |
60 | /* Save the async probe drivers' name from kernel cmdline */ |
61 | #define ASYNC_DRV_NAMES_MAX_LEN 256 | |
62 | static char async_probe_drv_names[ASYNC_DRV_NAMES_MAX_LEN]; | |
63 | ||
013c074f SG |
64 | /* |
65 | * In some cases, like suspend to RAM or hibernation, It might be reasonable | |
66 | * to prohibit probing of devices as it could be unsafe. | |
67 | * Once defer_all_probes is true all drivers probes will be forcibly deferred. | |
68 | */ | |
69 | static bool defer_all_probes; | |
70 | ||
41575335 | 71 | /* |
d1c3414c GL |
72 | * deferred_probe_work_func() - Retry probing devices in the active list. |
73 | */ | |
74 | static void deferred_probe_work_func(struct work_struct *work) | |
75 | { | |
76 | struct device *dev; | |
ef8a3fd6 | 77 | struct device_private *private; |
d1c3414c GL |
78 | /* |
79 | * This block processes every device in the deferred 'active' list. | |
80 | * Each device is removed from the active list and passed to | |
81 | * bus_probe_device() to re-attempt the probe. The loop continues | |
82 | * until every device in the active list is removed and retried. | |
83 | * | |
84 | * Note: Once the device is removed from the list and the mutex is | |
85 | * released, it is possible for the device get freed by another thread | |
86 | * and cause a illegal pointer dereference. This code uses | |
87 | * get/put_device() to ensure the device structure cannot disappear | |
88 | * from under our feet. | |
89 | */ | |
90 | mutex_lock(&deferred_probe_mutex); | |
91 | while (!list_empty(&deferred_probe_active_list)) { | |
ef8a3fd6 GKH |
92 | private = list_first_entry(&deferred_probe_active_list, |
93 | typeof(*dev->p), deferred_probe); | |
94 | dev = private->device; | |
95 | list_del_init(&private->deferred_probe); | |
d1c3414c GL |
96 | |
97 | get_device(dev); | |
98 | ||
8b0372a2 GKH |
99 | /* |
100 | * Drop the mutex while probing each device; the probe path may | |
101 | * manipulate the deferred list | |
102 | */ | |
d1c3414c | 103 | mutex_unlock(&deferred_probe_mutex); |
8153584e MB |
104 | |
105 | /* | |
106 | * Force the device to the end of the dpm_list since | |
107 | * the PM code assumes that the order we add things to | |
108 | * the list is a good order for suspend but deferred | |
109 | * probe makes that very unsafe. | |
110 | */ | |
494fd7b7 | 111 | device_pm_move_to_tail(dev); |
8153584e | 112 | |
d1c3414c | 113 | dev_dbg(dev, "Retrying from deferred list\n"); |
0a50f61c | 114 | bus_probe_device(dev); |
d1c3414c GL |
115 | mutex_lock(&deferred_probe_mutex); |
116 | ||
117 | put_device(dev); | |
118 | } | |
119 | mutex_unlock(&deferred_probe_mutex); | |
120 | } | |
121 | static DECLARE_WORK(deferred_probe_work, deferred_probe_work_func); | |
122 | ||
e7dd4010 | 123 | void driver_deferred_probe_add(struct device *dev) |
d1c3414c GL |
124 | { |
125 | mutex_lock(&deferred_probe_mutex); | |
ef8a3fd6 | 126 | if (list_empty(&dev->p->deferred_probe)) { |
d1c3414c | 127 | dev_dbg(dev, "Added to deferred list\n"); |
1d29cfa5 | 128 | list_add_tail(&dev->p->deferred_probe, &deferred_probe_pending_list); |
d1c3414c GL |
129 | } |
130 | mutex_unlock(&deferred_probe_mutex); | |
131 | } | |
132 | ||
133 | void driver_deferred_probe_del(struct device *dev) | |
134 | { | |
135 | mutex_lock(&deferred_probe_mutex); | |
ef8a3fd6 | 136 | if (!list_empty(&dev->p->deferred_probe)) { |
d1c3414c | 137 | dev_dbg(dev, "Removed from deferred list\n"); |
ef8a3fd6 | 138 | list_del_init(&dev->p->deferred_probe); |
d1c3414c GL |
139 | } |
140 | mutex_unlock(&deferred_probe_mutex); | |
141 | } | |
142 | ||
143 | static bool driver_deferred_probe_enable = false; | |
144 | /** | |
145 | * driver_deferred_probe_trigger() - Kick off re-probing deferred devices | |
146 | * | |
147 | * This functions moves all devices from the pending list to the active | |
148 | * list and schedules the deferred probe workqueue to process them. It | |
149 | * should be called anytime a driver is successfully bound to a device. | |
58b116bc GL |
150 | * |
151 | * Note, there is a race condition in multi-threaded probe. In the case where | |
152 | * more than one device is probing at the same time, it is possible for one | |
153 | * probe to complete successfully while another is about to defer. If the second | |
154 | * depends on the first, then it will get put on the pending list after the | |
9ba8af66 | 155 | * trigger event has already occurred and will be stuck there. |
58b116bc GL |
156 | * |
157 | * The atomic 'deferred_trigger_count' is used to determine if a successful | |
158 | * trigger has occurred in the midst of probing a driver. If the trigger count | |
159 | * changes in the midst of a probe, then deferred processing should be triggered | |
160 | * again. | |
d1c3414c GL |
161 | */ |
162 | static void driver_deferred_probe_trigger(void) | |
163 | { | |
164 | if (!driver_deferred_probe_enable) | |
165 | return; | |
166 | ||
8b0372a2 GKH |
167 | /* |
168 | * A successful probe means that all the devices in the pending list | |
d1c3414c | 169 | * should be triggered to be reprobed. Move all the deferred devices |
8b0372a2 GKH |
170 | * into the active list so they can be retried by the workqueue |
171 | */ | |
d1c3414c | 172 | mutex_lock(&deferred_probe_mutex); |
58b116bc | 173 | atomic_inc(&deferred_trigger_count); |
d1c3414c GL |
174 | list_splice_tail_init(&deferred_probe_pending_list, |
175 | &deferred_probe_active_list); | |
176 | mutex_unlock(&deferred_probe_mutex); | |
177 | ||
8b0372a2 GKH |
178 | /* |
179 | * Kick the re-probe thread. It may already be scheduled, but it is | |
180 | * safe to kick it again. | |
181 | */ | |
2c507e46 | 182 | schedule_work(&deferred_probe_work); |
d1c3414c GL |
183 | } |
184 | ||
013c074f | 185 | /** |
dbf03d65 | 186 | * device_block_probing() - Block/defer device's probes |
013c074f SG |
187 | * |
188 | * It will disable probing of devices and defer their probes instead. | |
189 | */ | |
190 | void device_block_probing(void) | |
191 | { | |
192 | defer_all_probes = true; | |
193 | /* sync with probes to avoid races. */ | |
194 | wait_for_device_probe(); | |
195 | } | |
196 | ||
197 | /** | |
198 | * device_unblock_probing() - Unblock/enable device's probes | |
199 | * | |
200 | * It will restore normal behavior and trigger re-probing of deferred | |
201 | * devices. | |
202 | */ | |
203 | void device_unblock_probing(void) | |
204 | { | |
205 | defer_all_probes = false; | |
206 | driver_deferred_probe_trigger(); | |
207 | } | |
208 | ||
28af109a JMC |
209 | /* |
210 | * deferred_devs_show() - Show the devices in the deferred probe pending list. | |
211 | */ | |
212 | static int deferred_devs_show(struct seq_file *s, void *data) | |
213 | { | |
214 | struct device_private *curr; | |
215 | ||
216 | mutex_lock(&deferred_probe_mutex); | |
217 | ||
218 | list_for_each_entry(curr, &deferred_probe_pending_list, deferred_probe) | |
219 | seq_printf(s, "%s\n", dev_name(curr->device)); | |
220 | ||
221 | mutex_unlock(&deferred_probe_mutex); | |
222 | ||
223 | return 0; | |
224 | } | |
225 | DEFINE_SHOW_ATTRIBUTE(deferred_devs); | |
226 | ||
25b4e70d RH |
227 | static int deferred_probe_timeout = -1; |
228 | static int __init deferred_probe_timeout_setup(char *str) | |
229 | { | |
63c98047 MS |
230 | int timeout; |
231 | ||
232 | if (!kstrtoint(str, 10, &timeout)) | |
233 | deferred_probe_timeout = timeout; | |
25b4e70d RH |
234 | return 1; |
235 | } | |
236 | __setup("deferred_probe_timeout=", deferred_probe_timeout_setup); | |
237 | ||
62a6bc3a TR |
238 | static int __driver_deferred_probe_check_state(struct device *dev) |
239 | { | |
240 | if (!initcalls_done) | |
241 | return -EPROBE_DEFER; | |
242 | ||
243 | if (!deferred_probe_timeout) { | |
244 | dev_WARN(dev, "deferred probe timeout, ignoring dependency"); | |
245 | return -ETIMEDOUT; | |
246 | } | |
247 | ||
248 | return 0; | |
249 | } | |
250 | ||
25b4e70d RH |
251 | /** |
252 | * driver_deferred_probe_check_state() - Check deferred probe state | |
253 | * @dev: device to check | |
254 | * | |
255 | * Returns -ENODEV if init is done and all built-in drivers have had a chance | |
256 | * to probe (i.e. initcalls are done), -ETIMEDOUT if deferred probe debug | |
257 | * timeout has expired, or -EPROBE_DEFER if none of those conditions are met. | |
258 | * | |
259 | * Drivers or subsystems can opt-in to calling this function instead of directly | |
260 | * returning -EPROBE_DEFER. | |
261 | */ | |
262 | int driver_deferred_probe_check_state(struct device *dev) | |
263 | { | |
62a6bc3a TR |
264 | int ret; |
265 | ||
266 | ret = __driver_deferred_probe_check_state(dev); | |
267 | if (ret < 0) | |
268 | return ret; | |
269 | ||
270 | dev_warn(dev, "ignoring dependency for device, assuming no driver"); | |
271 | ||
272 | return -ENODEV; | |
273 | } | |
274 | ||
275 | /** | |
276 | * driver_deferred_probe_check_state_continue() - check deferred probe state | |
277 | * @dev: device to check | |
278 | * | |
279 | * Returns -ETIMEDOUT if deferred probe debug timeout has expired, or | |
280 | * -EPROBE_DEFER otherwise. | |
281 | * | |
282 | * Drivers or subsystems can opt-in to calling this function instead of | |
283 | * directly returning -EPROBE_DEFER. | |
284 | * | |
285 | * This is similar to driver_deferred_probe_check_state(), but it allows the | |
286 | * subsystem to keep deferring probe after built-in drivers have had a chance | |
287 | * to probe. One scenario where that is useful is if built-in drivers rely on | |
288 | * resources that are provided by modular drivers. | |
289 | */ | |
290 | int driver_deferred_probe_check_state_continue(struct device *dev) | |
291 | { | |
292 | int ret; | |
293 | ||
294 | ret = __driver_deferred_probe_check_state(dev); | |
295 | if (ret < 0) | |
296 | return ret; | |
297 | ||
25b4e70d RH |
298 | return -EPROBE_DEFER; |
299 | } | |
300 | ||
301 | static void deferred_probe_timeout_work_func(struct work_struct *work) | |
302 | { | |
303 | struct device_private *private, *p; | |
304 | ||
305 | deferred_probe_timeout = 0; | |
306 | driver_deferred_probe_trigger(); | |
307 | flush_work(&deferred_probe_work); | |
308 | ||
309 | list_for_each_entry_safe(private, p, &deferred_probe_pending_list, deferred_probe) | |
310 | dev_info(private->device, "deferred probe pending"); | |
311 | } | |
312 | static DECLARE_DELAYED_WORK(deferred_probe_timeout_work, deferred_probe_timeout_work_func); | |
313 | ||
d1c3414c GL |
314 | /** |
315 | * deferred_probe_initcall() - Enable probing of deferred devices | |
316 | * | |
317 | * We don't want to get in the way when the bulk of drivers are getting probed. | |
318 | * Instead, this initcall makes sure that deferred probing is delayed until | |
319 | * late_initcall time. | |
320 | */ | |
321 | static int deferred_probe_initcall(void) | |
322 | { | |
28af109a JMC |
323 | deferred_devices = debugfs_create_file("devices_deferred", 0444, NULL, |
324 | NULL, &deferred_devs_fops); | |
325 | ||
d1c3414c GL |
326 | driver_deferred_probe_enable = true; |
327 | driver_deferred_probe_trigger(); | |
d72cca1e | 328 | /* Sort as many dependencies as possible before exiting initcalls */ |
2c507e46 | 329 | flush_work(&deferred_probe_work); |
25b4e70d RH |
330 | initcalls_done = true; |
331 | ||
332 | /* | |
333 | * Trigger deferred probe again, this time we won't defer anything | |
334 | * that is optional | |
335 | */ | |
336 | driver_deferred_probe_trigger(); | |
337 | flush_work(&deferred_probe_work); | |
338 | ||
339 | if (deferred_probe_timeout > 0) { | |
340 | schedule_delayed_work(&deferred_probe_timeout_work, | |
341 | deferred_probe_timeout * HZ); | |
342 | } | |
d1c3414c GL |
343 | return 0; |
344 | } | |
345 | late_initcall(deferred_probe_initcall); | |
07e4a3e2 | 346 | |
28af109a JMC |
347 | static void __exit deferred_probe_exit(void) |
348 | { | |
349 | debugfs_remove_recursive(deferred_devices); | |
350 | } | |
351 | __exitcall(deferred_probe_exit); | |
352 | ||
6b9cb427 TV |
353 | /** |
354 | * device_is_bound() - Check if device is bound to a driver | |
355 | * @dev: device to check | |
356 | * | |
357 | * Returns true if passed device has already finished probing successfully | |
358 | * against a driver. | |
359 | * | |
360 | * This function must be called with the device lock held. | |
361 | */ | |
362 | bool device_is_bound(struct device *dev) | |
363 | { | |
3ded9104 | 364 | return dev->p && klist_node_attached(&dev->p->knode_driver); |
6b9cb427 TV |
365 | } |
366 | ||
1901fb26 | 367 | static void driver_bound(struct device *dev) |
07e4a3e2 | 368 | { |
6b9cb427 | 369 | if (device_is_bound(dev)) { |
f86db396 | 370 | printk(KERN_WARNING "%s: device %s already bound\n", |
2b3a302a | 371 | __func__, kobject_name(&dev->kobj)); |
1901fb26 | 372 | return; |
f86db396 | 373 | } |
4c898c7f | 374 | |
94f8cc0e FR |
375 | pr_debug("driver: '%s': %s: bound to device '%s'\n", dev->driver->name, |
376 | __func__, dev_name(dev)); | |
116af378 | 377 | |
fbb88fad | 378 | klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices); |
9ed98953 | 379 | device_links_driver_bound(dev); |
fbb88fad | 380 | |
aa8e54b5 TV |
381 | device_pm_check_callbacks(dev); |
382 | ||
8b0372a2 GKH |
383 | /* |
384 | * Make sure the device is no longer in one of the deferred lists and | |
385 | * kick off retrying all pending devices | |
386 | */ | |
d1c3414c GL |
387 | driver_deferred_probe_del(dev); |
388 | driver_deferred_probe_trigger(); | |
389 | ||
116af378 | 390 | if (dev->bus) |
c6f7e72a | 391 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
116af378 | 392 | BUS_NOTIFY_BOUND_DRIVER, dev); |
1455cf8d DT |
393 | |
394 | kobject_uevent(&dev->kobj, KOBJ_BIND); | |
1901fb26 KS |
395 | } |
396 | ||
3c47d19f AS |
397 | static ssize_t coredump_store(struct device *dev, struct device_attribute *attr, |
398 | const char *buf, size_t count) | |
399 | { | |
400 | device_lock(dev); | |
1fe56e0c | 401 | dev->driver->coredump(dev); |
3c47d19f AS |
402 | device_unlock(dev); |
403 | ||
404 | return count; | |
405 | } | |
406 | static DEVICE_ATTR_WO(coredump); | |
407 | ||
1901fb26 KS |
408 | static int driver_sysfs_add(struct device *dev) |
409 | { | |
410 | int ret; | |
411 | ||
45daef0f MD |
412 | if (dev->bus) |
413 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
414 | BUS_NOTIFY_BIND_DRIVER, dev); | |
415 | ||
e5dd1278 | 416 | ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj, |
3c47d19f AS |
417 | kobject_name(&dev->kobj)); |
418 | if (ret) | |
419 | goto fail; | |
420 | ||
421 | ret = sysfs_create_link(&dev->kobj, &dev->driver->p->kobj, | |
422 | "driver"); | |
423 | if (ret) | |
424 | goto rm_dev; | |
425 | ||
426 | if (!IS_ENABLED(CONFIG_DEV_COREDUMP) || !dev->driver->coredump || | |
427 | !device_create_file(dev, &dev_attr_coredump)) | |
428 | return 0; | |
429 | ||
430 | sysfs_remove_link(&dev->kobj, "driver"); | |
431 | ||
432 | rm_dev: | |
433 | sysfs_remove_link(&dev->driver->p->kobj, | |
07e4a3e2 | 434 | kobject_name(&dev->kobj)); |
3c47d19f AS |
435 | |
436 | fail: | |
f86db396 | 437 | return ret; |
07e4a3e2 PM |
438 | } |
439 | ||
1901fb26 KS |
440 | static void driver_sysfs_remove(struct device *dev) |
441 | { | |
442 | struct device_driver *drv = dev->driver; | |
443 | ||
444 | if (drv) { | |
3c47d19f AS |
445 | if (drv->coredump) |
446 | device_remove_file(dev, &dev_attr_coredump); | |
e5dd1278 | 447 | sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj)); |
1901fb26 KS |
448 | sysfs_remove_link(&dev->kobj, "driver"); |
449 | } | |
450 | } | |
451 | ||
452 | /** | |
4a3ad20c GKH |
453 | * device_bind_driver - bind a driver to one device. |
454 | * @dev: device. | |
1901fb26 | 455 | * |
4a3ad20c GKH |
456 | * Allow manual attachment of a driver to a device. |
457 | * Caller must have already set @dev->driver. | |
1901fb26 | 458 | * |
4a3ad20c GKH |
459 | * Note that this does not modify the bus reference count |
460 | * nor take the bus's rwsem. Please verify those are accounted | |
461 | * for before calling this. (It is ok to call with no other effort | |
462 | * from a driver's probe() method.) | |
1901fb26 | 463 | * |
8e9394ce | 464 | * This function must be called with the device lock held. |
1901fb26 KS |
465 | */ |
466 | int device_bind_driver(struct device *dev) | |
467 | { | |
cb986b74 CH |
468 | int ret; |
469 | ||
470 | ret = driver_sysfs_add(dev); | |
471 | if (!ret) | |
472 | driver_bound(dev); | |
14b6257a AS |
473 | else if (dev->bus) |
474 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
475 | BUS_NOTIFY_DRIVER_NOT_BOUND, dev); | |
cb986b74 | 476 | return ret; |
1901fb26 | 477 | } |
4a3ad20c | 478 | EXPORT_SYMBOL_GPL(device_bind_driver); |
1901fb26 | 479 | |
d779249e | 480 | static atomic_t probe_count = ATOMIC_INIT(0); |
735a7ffb AM |
481 | static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue); |
482 | ||
0ff26c66 AH |
483 | static void driver_deferred_probe_add_trigger(struct device *dev, |
484 | int local_trigger_count) | |
485 | { | |
486 | driver_deferred_probe_add(dev); | |
487 | /* Did a trigger occur while probing? Need to re-trigger if yes */ | |
488 | if (local_trigger_count != atomic_read(&deferred_trigger_count)) | |
489 | driver_deferred_probe_trigger(); | |
490 | } | |
491 | ||
21c7f30b | 492 | static int really_probe(struct device *dev, struct device_driver *drv) |
07e4a3e2 | 493 | { |
013c074f | 494 | int ret = -EPROBE_DEFER; |
58b116bc | 495 | int local_trigger_count = atomic_read(&deferred_trigger_count); |
c5f06274 RH |
496 | bool test_remove = IS_ENABLED(CONFIG_DEBUG_TEST_DRIVER_REMOVE) && |
497 | !drv->suppress_bind_attrs; | |
07e4a3e2 | 498 | |
013c074f SG |
499 | if (defer_all_probes) { |
500 | /* | |
501 | * Value of defer_all_probes can be set only by | |
dbf03d65 | 502 | * device_block_probing() which, in turn, will call |
013c074f SG |
503 | * wait_for_device_probe() right after that to avoid any races. |
504 | */ | |
505 | dev_dbg(dev, "Driver %s force probe deferral\n", drv->name); | |
506 | driver_deferred_probe_add(dev); | |
507 | return ret; | |
508 | } | |
509 | ||
9ed98953 | 510 | ret = device_links_check_suppliers(dev); |
0ff26c66 AH |
511 | if (ret == -EPROBE_DEFER) |
512 | driver_deferred_probe_add_trigger(dev, local_trigger_count); | |
9ed98953 RW |
513 | if (ret) |
514 | return ret; | |
515 | ||
d779249e | 516 | atomic_inc(&probe_count); |
7dc72b28 | 517 | pr_debug("bus: '%s': %s: probing driver %s with device %s\n", |
1e0b2cf9 | 518 | drv->bus->name, __func__, drv->name, dev_name(dev)); |
7c35e699 GU |
519 | if (!list_empty(&dev->devres_head)) { |
520 | dev_crit(dev, "Resources present before probing\n"); | |
521 | return -EBUSY; | |
522 | } | |
07e4a3e2 | 523 | |
bea5b158 | 524 | re_probe: |
07e4a3e2 | 525 | dev->driver = drv; |
ab78029e LW |
526 | |
527 | /* If using pinctrl, bind pins now before probing */ | |
528 | ret = pinctrl_bind_pins(dev); | |
529 | if (ret) | |
14b6257a | 530 | goto pinctrl_bind_failed; |
ab78029e | 531 | |
ccf640f4 CH |
532 | if (dev->bus->dma_configure) { |
533 | ret = dev->bus->dma_configure(dev); | |
534 | if (ret) | |
0b777eee | 535 | goto probe_failed; |
ccf640f4 | 536 | } |
09515ef5 | 537 | |
1901fb26 KS |
538 | if (driver_sysfs_add(dev)) { |
539 | printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n", | |
1e0b2cf9 | 540 | __func__, dev_name(dev)); |
1901fb26 KS |
541 | goto probe_failed; |
542 | } | |
543 | ||
e90d5532 RW |
544 | if (dev->pm_domain && dev->pm_domain->activate) { |
545 | ret = dev->pm_domain->activate(dev); | |
546 | if (ret) | |
547 | goto probe_failed; | |
548 | } | |
549 | ||
594c8281 RK |
550 | if (dev->bus->probe) { |
551 | ret = dev->bus->probe(dev); | |
1901fb26 | 552 | if (ret) |
d779249e | 553 | goto probe_failed; |
594c8281 | 554 | } else if (drv->probe) { |
0d3e5a2e | 555 | ret = drv->probe(dev); |
1901fb26 | 556 | if (ret) |
d779249e | 557 | goto probe_failed; |
f86db396 | 558 | } |
1901fb26 | 559 | |
23b69044 DT |
560 | if (device_add_groups(dev, drv->dev_groups)) { |
561 | dev_err(dev, "device_add_groups() failed\n"); | |
562 | goto dev_groups_failed; | |
563 | } | |
564 | ||
bea5b158 RH |
565 | if (test_remove) { |
566 | test_remove = false; | |
567 | ||
23b69044 DT |
568 | device_remove_groups(dev, drv->dev_groups); |
569 | ||
bdacd1b4 | 570 | if (dev->bus->remove) |
bea5b158 RH |
571 | dev->bus->remove(dev); |
572 | else if (drv->remove) | |
573 | drv->remove(dev); | |
574 | ||
575 | devres_release_all(dev); | |
576 | driver_sysfs_remove(dev); | |
577 | dev->driver = NULL; | |
578 | dev_set_drvdata(dev, NULL); | |
579 | if (dev->pm_domain && dev->pm_domain->dismiss) | |
580 | dev->pm_domain->dismiss(dev); | |
581 | pm_runtime_reinit(dev); | |
582 | ||
583 | goto re_probe; | |
584 | } | |
585 | ||
ef0eebc0 DA |
586 | pinctrl_init_done(dev); |
587 | ||
e90d5532 RW |
588 | if (dev->pm_domain && dev->pm_domain->sync) |
589 | dev->pm_domain->sync(dev); | |
590 | ||
1901fb26 | 591 | driver_bound(dev); |
0d3e5a2e | 592 | ret = 1; |
7dc72b28 | 593 | pr_debug("bus: '%s': %s: bound device %s to driver %s\n", |
1e0b2cf9 | 594 | drv->bus->name, __func__, dev_name(dev), drv->name); |
d779249e | 595 | goto done; |
0d3e5a2e | 596 | |
23b69044 DT |
597 | dev_groups_failed: |
598 | if (dev->bus->remove) | |
599 | dev->bus->remove(dev); | |
600 | else if (drv->remove) | |
601 | drv->remove(dev); | |
d779249e | 602 | probe_failed: |
14b6257a AS |
603 | if (dev->bus) |
604 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
605 | BUS_NOTIFY_DRIVER_NOT_BOUND, dev); | |
606 | pinctrl_bind_failed: | |
9ed98953 | 607 | device_links_no_driver(dev); |
9ac7849e | 608 | devres_release_all(dev); |
0b777eee | 609 | arch_teardown_dma_ops(dev); |
1901fb26 KS |
610 | driver_sysfs_remove(dev); |
611 | dev->driver = NULL; | |
0998d063 | 612 | dev_set_drvdata(dev, NULL); |
e90d5532 RW |
613 | if (dev->pm_domain && dev->pm_domain->dismiss) |
614 | dev->pm_domain->dismiss(dev); | |
5de85b9d | 615 | pm_runtime_reinit(dev); |
08810a41 | 616 | dev_pm_set_driver_flags(dev, 0); |
1901fb26 | 617 | |
bb2b4075 SS |
618 | switch (ret) { |
619 | case -EPROBE_DEFER: | |
d1c3414c | 620 | /* Driver requested deferred probing */ |
13fcffbb | 621 | dev_dbg(dev, "Driver %s requests probe deferral\n", drv->name); |
0ff26c66 | 622 | driver_deferred_probe_add_trigger(dev, local_trigger_count); |
bb2b4075 SS |
623 | break; |
624 | case -ENODEV: | |
625 | case -ENXIO: | |
626 | pr_debug("%s: probe of %s rejects match %d\n", | |
627 | drv->name, dev_name(dev), ret); | |
628 | break; | |
629 | default: | |
0d3e5a2e PM |
630 | /* driver matched but the probe failed */ |
631 | printk(KERN_WARNING | |
632 | "%s: probe of %s failed with error %d\n", | |
1e0b2cf9 | 633 | drv->name, dev_name(dev), ret); |
0d3e5a2e | 634 | } |
c578abbc CH |
635 | /* |
636 | * Ignore errors returned by ->probe so that the next driver can try | |
637 | * its luck. | |
638 | */ | |
639 | ret = 0; | |
d779249e | 640 | done: |
d779249e | 641 | atomic_dec(&probe_count); |
735a7ffb | 642 | wake_up(&probe_waitqueue); |
d779249e GKH |
643 | return ret; |
644 | } | |
645 | ||
0a50f61c TP |
646 | /* |
647 | * For initcall_debug, show the driver probe time. | |
648 | */ | |
649 | static int really_probe_debug(struct device *dev, struct device_driver *drv) | |
650 | { | |
651 | ktime_t calltime, delta, rettime; | |
652 | int ret; | |
653 | ||
654 | calltime = ktime_get(); | |
655 | ret = really_probe(dev, drv); | |
656 | rettime = ktime_get(); | |
657 | delta = ktime_sub(rettime, calltime); | |
658 | printk(KERN_DEBUG "probe of %s returned %d after %lld usecs\n", | |
659 | dev_name(dev), ret, (s64) ktime_to_us(delta)); | |
660 | return ret; | |
661 | } | |
662 | ||
d779249e GKH |
663 | /** |
664 | * driver_probe_done | |
665 | * Determine if the probe sequence is finished or not. | |
666 | * | |
667 | * Should somehow figure out how to use a semaphore, not an atomic variable... | |
668 | */ | |
669 | int driver_probe_done(void) | |
670 | { | |
2b3a302a | 671 | pr_debug("%s: probe_count = %d\n", __func__, |
d779249e GKH |
672 | atomic_read(&probe_count)); |
673 | if (atomic_read(&probe_count)) | |
674 | return -EBUSY; | |
675 | return 0; | |
676 | } | |
677 | ||
216773a7 AV |
678 | /** |
679 | * wait_for_device_probe | |
680 | * Wait for device probing to be completed. | |
216773a7 | 681 | */ |
b23530eb | 682 | void wait_for_device_probe(void) |
216773a7 | 683 | { |
013c074f | 684 | /* wait for the deferred probe workqueue to finish */ |
2c507e46 | 685 | flush_work(&deferred_probe_work); |
013c074f | 686 | |
216773a7 | 687 | /* wait for the known devices to complete their probing */ |
b23530eb | 688 | wait_event(probe_waitqueue, atomic_read(&probe_count) == 0); |
216773a7 | 689 | async_synchronize_full(); |
216773a7 | 690 | } |
d4d5291c | 691 | EXPORT_SYMBOL_GPL(wait_for_device_probe); |
216773a7 | 692 | |
d779249e GKH |
693 | /** |
694 | * driver_probe_device - attempt to bind device & driver together | |
695 | * @drv: driver to bind a device to | |
696 | * @dev: device to try to bind to the driver | |
697 | * | |
49b420a1 | 698 | * This function returns -ENODEV if the device is not registered, |
af901ca1 | 699 | * 1 if the device is bound successfully and 0 otherwise. |
d779249e | 700 | * |
8e9394ce GKH |
701 | * This function must be called with @dev lock held. When called for a |
702 | * USB interface, @dev->parent lock must be held as well. | |
ddef08dd RW |
703 | * |
704 | * If the device has a parent, runtime-resume the parent before driver probing. | |
d779249e | 705 | */ |
4a3ad20c | 706 | int driver_probe_device(struct device_driver *drv, struct device *dev) |
d779249e | 707 | { |
d779249e GKH |
708 | int ret = 0; |
709 | ||
f2eaae19 AS |
710 | if (!device_is_registered(dev)) |
711 | return -ENODEV; | |
d779249e | 712 | |
7dc72b28 | 713 | pr_debug("bus: '%s': %s: matched device %s with driver %s\n", |
1e0b2cf9 | 714 | drv->bus->name, __func__, dev_name(dev), drv->name); |
d779249e | 715 | |
b06c0b2f | 716 | pm_runtime_get_suppliers(dev); |
ddef08dd RW |
717 | if (dev->parent) |
718 | pm_runtime_get_sync(dev->parent); | |
719 | ||
5e928f77 | 720 | pm_runtime_barrier(dev); |
0a50f61c TP |
721 | if (initcall_debug) |
722 | ret = really_probe_debug(dev, drv); | |
723 | else | |
724 | ret = really_probe(dev, drv); | |
fa180eb4 | 725 | pm_request_idle(dev); |
d779249e | 726 | |
ddef08dd RW |
727 | if (dev->parent) |
728 | pm_runtime_put(dev->parent); | |
729 | ||
b06c0b2f | 730 | pm_runtime_put_suppliers(dev); |
0d3e5a2e | 731 | return ret; |
07e4a3e2 PM |
732 | } |
733 | ||
1ea61b68 FT |
734 | static inline bool cmdline_requested_async_probing(const char *drv_name) |
735 | { | |
736 | return parse_option_str(async_probe_drv_names, drv_name); | |
737 | } | |
738 | ||
739 | /* The option format is "driver_async_probe=drv_name1,drv_name2,..." */ | |
740 | static int __init save_async_options(char *buf) | |
741 | { | |
742 | if (strlen(buf) >= ASYNC_DRV_NAMES_MAX_LEN) | |
743 | printk(KERN_WARNING | |
744 | "Too long list of driver names for 'driver_async_probe'!\n"); | |
745 | ||
746 | strlcpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN); | |
747 | return 0; | |
748 | } | |
749 | __setup("driver_async_probe=", save_async_options); | |
750 | ||
765230b5 | 751 | bool driver_allows_async_probing(struct device_driver *drv) |
2287c322 | 752 | { |
d173a137 LR |
753 | switch (drv->probe_type) { |
754 | case PROBE_PREFER_ASYNCHRONOUS: | |
f2411da7 LR |
755 | return true; |
756 | ||
d173a137 LR |
757 | case PROBE_FORCE_SYNCHRONOUS: |
758 | return false; | |
759 | ||
760 | default: | |
1ea61b68 FT |
761 | if (cmdline_requested_async_probing(drv->name)) |
762 | return true; | |
763 | ||
80c6e146 | 764 | if (module_requested_async_probing(drv->owner)) |
d173a137 | 765 | return true; |
f2411da7 | 766 | |
d173a137 LR |
767 | return false; |
768 | } | |
765230b5 DT |
769 | } |
770 | ||
771 | struct device_attach_data { | |
772 | struct device *dev; | |
773 | ||
774 | /* | |
775 | * Indicates whether we are are considering asynchronous probing or | |
776 | * not. Only initial binding after device or driver registration | |
777 | * (including deferral processing) may be done asynchronously, the | |
778 | * rest is always synchronous, as we expect it is being done by | |
779 | * request from userspace. | |
780 | */ | |
781 | bool check_async; | |
782 | ||
783 | /* | |
784 | * Indicates if we are binding synchronous or asynchronous drivers. | |
785 | * When asynchronous probing is enabled we'll execute 2 passes | |
786 | * over drivers: first pass doing synchronous probing and second | |
787 | * doing asynchronous probing (if synchronous did not succeed - | |
788 | * most likely because there was no driver requiring synchronous | |
789 | * probing - and we found asynchronous driver during first pass). | |
790 | * The 2 passes are done because we can't shoot asynchronous | |
791 | * probe for given device and driver from bus_for_each_drv() since | |
792 | * driver pointer is not guaranteed to stay valid once | |
793 | * bus_for_each_drv() iterates to the next driver on the bus. | |
794 | */ | |
795 | bool want_async; | |
796 | ||
797 | /* | |
798 | * We'll set have_async to 'true' if, while scanning for matching | |
799 | * driver, we'll encounter one that requests asynchronous probing. | |
800 | */ | |
801 | bool have_async; | |
802 | }; | |
803 | ||
804 | static int __device_attach_driver(struct device_driver *drv, void *_data) | |
805 | { | |
806 | struct device_attach_data *data = _data; | |
807 | struct device *dev = data->dev; | |
808 | bool async_allowed; | |
656b8035 | 809 | int ret; |
765230b5 | 810 | |
656b8035 TV |
811 | ret = driver_match_device(drv, dev); |
812 | if (ret == 0) { | |
813 | /* no match */ | |
49b420a1 | 814 | return 0; |
656b8035 TV |
815 | } else if (ret == -EPROBE_DEFER) { |
816 | dev_dbg(dev, "Device match requests probe deferral\n"); | |
817 | driver_deferred_probe_add(dev); | |
818 | } else if (ret < 0) { | |
819 | dev_dbg(dev, "Bus failed to match device: %d", ret); | |
820 | return ret; | |
821 | } /* ret > 0 means positive match */ | |
49b420a1 | 822 | |
765230b5 DT |
823 | async_allowed = driver_allows_async_probing(drv); |
824 | ||
825 | if (async_allowed) | |
826 | data->have_async = true; | |
827 | ||
828 | if (data->check_async && async_allowed != data->want_async) | |
829 | return 0; | |
830 | ||
0d3e5a2e | 831 | return driver_probe_device(drv, dev); |
2287c322 PM |
832 | } |
833 | ||
765230b5 DT |
834 | static void __device_attach_async_helper(void *_dev, async_cookie_t cookie) |
835 | { | |
836 | struct device *dev = _dev; | |
837 | struct device_attach_data data = { | |
838 | .dev = dev, | |
839 | .check_async = true, | |
840 | .want_async = true, | |
841 | }; | |
842 | ||
843 | device_lock(dev); | |
844 | ||
3451a495 AD |
845 | /* |
846 | * Check if device has already been removed or claimed. This may | |
847 | * happen with driver loading, device discovery/registration, | |
848 | * and deferred probe processing happens all at once with | |
849 | * multiple threads. | |
850 | */ | |
851 | if (dev->p->dead || dev->driver) | |
852 | goto out_unlock; | |
853 | ||
ddef08dd RW |
854 | if (dev->parent) |
855 | pm_runtime_get_sync(dev->parent); | |
856 | ||
765230b5 DT |
857 | bus_for_each_drv(dev->bus, NULL, &data, __device_attach_driver); |
858 | dev_dbg(dev, "async probe completed\n"); | |
859 | ||
860 | pm_request_idle(dev); | |
861 | ||
ddef08dd RW |
862 | if (dev->parent) |
863 | pm_runtime_put(dev->parent); | |
3451a495 | 864 | out_unlock: |
765230b5 DT |
865 | device_unlock(dev); |
866 | ||
867 | put_device(dev); | |
868 | } | |
869 | ||
802a87fd | 870 | static int __device_attach(struct device *dev, bool allow_async) |
07e4a3e2 | 871 | { |
0d3e5a2e PM |
872 | int ret = 0; |
873 | ||
8e9394ce | 874 | device_lock(dev); |
07e4a3e2 | 875 | if (dev->driver) { |
6b9cb427 | 876 | if (device_is_bound(dev)) { |
8497d6a2 SO |
877 | ret = 1; |
878 | goto out_unlock; | |
879 | } | |
f86db396 AM |
880 | ret = device_bind_driver(dev); |
881 | if (ret == 0) | |
882 | ret = 1; | |
c6a46696 CH |
883 | else { |
884 | dev->driver = NULL; | |
885 | ret = 0; | |
886 | } | |
21c7f30b | 887 | } else { |
765230b5 DT |
888 | struct device_attach_data data = { |
889 | .dev = dev, | |
890 | .check_async = allow_async, | |
891 | .want_async = false, | |
892 | }; | |
893 | ||
ddef08dd RW |
894 | if (dev->parent) |
895 | pm_runtime_get_sync(dev->parent); | |
896 | ||
765230b5 DT |
897 | ret = bus_for_each_drv(dev->bus, NULL, &data, |
898 | __device_attach_driver); | |
899 | if (!ret && allow_async && data.have_async) { | |
900 | /* | |
901 | * If we could not find appropriate driver | |
902 | * synchronously and we are allowed to do | |
903 | * async probes and there are drivers that | |
904 | * want to probe asynchronously, we'll | |
905 | * try them. | |
906 | */ | |
907 | dev_dbg(dev, "scheduling asynchronous probe\n"); | |
908 | get_device(dev); | |
c37e20ea | 909 | async_schedule_dev(__device_attach_async_helper, dev); |
765230b5 DT |
910 | } else { |
911 | pm_request_idle(dev); | |
912 | } | |
ddef08dd RW |
913 | |
914 | if (dev->parent) | |
915 | pm_runtime_put(dev->parent); | |
21c7f30b | 916 | } |
8497d6a2 | 917 | out_unlock: |
8e9394ce | 918 | device_unlock(dev); |
0d3e5a2e | 919 | return ret; |
2287c322 | 920 | } |
765230b5 DT |
921 | |
922 | /** | |
923 | * device_attach - try to attach device to a driver. | |
924 | * @dev: device. | |
925 | * | |
926 | * Walk the list of drivers that the bus has and call | |
927 | * driver_probe_device() for each pair. If a compatible | |
928 | * pair is found, break out and return. | |
929 | * | |
930 | * Returns 1 if the device was bound to a driver; | |
931 | * 0 if no matching driver was found; | |
932 | * -ENODEV if the device is not registered. | |
933 | * | |
934 | * When called for a USB interface, @dev->parent lock must be held. | |
935 | */ | |
936 | int device_attach(struct device *dev) | |
937 | { | |
938 | return __device_attach(dev, false); | |
939 | } | |
4a3ad20c | 940 | EXPORT_SYMBOL_GPL(device_attach); |
2287c322 | 941 | |
765230b5 DT |
942 | void device_initial_probe(struct device *dev) |
943 | { | |
944 | __device_attach(dev, true); | |
945 | } | |
946 | ||
ed88747c AD |
947 | /* |
948 | * __device_driver_lock - acquire locks needed to manipulate dev->drv | |
949 | * @dev: Device we will update driver info for | |
950 | * @parent: Parent device. Needed if the bus requires parent lock | |
951 | * | |
952 | * This function will take the required locks for manipulating dev->drv. | |
953 | * Normally this will just be the @dev lock, but when called for a USB | |
954 | * interface, @parent lock will be held as well. | |
955 | */ | |
956 | static void __device_driver_lock(struct device *dev, struct device *parent) | |
957 | { | |
958 | if (parent && dev->bus->need_parent_lock) | |
959 | device_lock(parent); | |
960 | device_lock(dev); | |
961 | } | |
962 | ||
963 | /* | |
964 | * __device_driver_unlock - release locks needed to manipulate dev->drv | |
965 | * @dev: Device we will update driver info for | |
966 | * @parent: Parent device. Needed if the bus requires parent lock | |
967 | * | |
968 | * This function will release the required locks for manipulating dev->drv. | |
969 | * Normally this will just be the the @dev lock, but when called for a | |
970 | * USB interface, @parent lock will be released as well. | |
971 | */ | |
972 | static void __device_driver_unlock(struct device *dev, struct device *parent) | |
973 | { | |
974 | device_unlock(dev); | |
975 | if (parent && dev->bus->need_parent_lock) | |
976 | device_unlock(parent); | |
977 | } | |
978 | ||
979 | /** | |
980 | * device_driver_attach - attach a specific driver to a specific device | |
981 | * @drv: Driver to attach | |
982 | * @dev: Device to attach it to | |
983 | * | |
984 | * Manually attach driver to a device. Will acquire both @dev lock and | |
985 | * @dev->parent lock if needed. | |
986 | */ | |
987 | int device_driver_attach(struct device_driver *drv, struct device *dev) | |
988 | { | |
989 | int ret = 0; | |
990 | ||
991 | __device_driver_lock(dev, dev->parent); | |
992 | ||
993 | /* | |
994 | * If device has been removed or someone has already successfully | |
995 | * bound a driver before us just skip the driver probe call. | |
996 | */ | |
997 | if (!dev->p->dead && !dev->driver) | |
998 | ret = driver_probe_device(drv, dev); | |
999 | ||
1000 | __device_driver_unlock(dev, dev->parent); | |
1001 | ||
1002 | return ret; | |
1003 | } | |
1004 | ||
ef0ff683 AD |
1005 | static void __driver_attach_async_helper(void *_dev, async_cookie_t cookie) |
1006 | { | |
1007 | struct device *dev = _dev; | |
1008 | struct device_driver *drv; | |
1009 | int ret = 0; | |
1010 | ||
1011 | __device_driver_lock(dev, dev->parent); | |
1012 | ||
1013 | drv = dev->p->async_driver; | |
1014 | ||
1015 | /* | |
1016 | * If device has been removed or someone has already successfully | |
1017 | * bound a driver before us just skip the driver probe call. | |
1018 | */ | |
1019 | if (!dev->p->dead && !dev->driver) | |
1020 | ret = driver_probe_device(drv, dev); | |
1021 | ||
1022 | __device_driver_unlock(dev, dev->parent); | |
1023 | ||
1024 | dev_dbg(dev, "driver %s async attach completed: %d\n", drv->name, ret); | |
1025 | ||
1026 | put_device(dev); | |
1027 | } | |
1028 | ||
4a3ad20c | 1029 | static int __driver_attach(struct device *dev, void *data) |
2287c322 | 1030 | { |
4a3ad20c | 1031 | struct device_driver *drv = data; |
656b8035 | 1032 | int ret; |
0d3e5a2e PM |
1033 | |
1034 | /* | |
1035 | * Lock device and try to bind to it. We drop the error | |
1036 | * here and always return 0, because we need to keep trying | |
1037 | * to bind to devices and some drivers will return an error | |
1038 | * simply if it didn't support the device. | |
1039 | * | |
1040 | * driver_probe_device() will spit a warning if there | |
1041 | * is an error. | |
1042 | */ | |
1043 | ||
656b8035 TV |
1044 | ret = driver_match_device(drv, dev); |
1045 | if (ret == 0) { | |
1046 | /* no match */ | |
6cd49586 | 1047 | return 0; |
656b8035 TV |
1048 | } else if (ret == -EPROBE_DEFER) { |
1049 | dev_dbg(dev, "Device match requests probe deferral\n"); | |
1050 | driver_deferred_probe_add(dev); | |
1051 | } else if (ret < 0) { | |
1052 | dev_dbg(dev, "Bus failed to match device: %d", ret); | |
1053 | return ret; | |
1054 | } /* ret > 0 means positive match */ | |
6cd49586 | 1055 | |
ef0ff683 AD |
1056 | if (driver_allows_async_probing(drv)) { |
1057 | /* | |
1058 | * Instead of probing the device synchronously we will | |
1059 | * probe it asynchronously to allow for more parallelism. | |
1060 | * | |
1061 | * We only take the device lock here in order to guarantee | |
1062 | * that the dev->driver and async_driver fields are protected | |
1063 | */ | |
1064 | dev_dbg(dev, "probing driver %s asynchronously\n", drv->name); | |
1065 | device_lock(dev); | |
1066 | if (!dev->driver) { | |
1067 | get_device(dev); | |
1068 | dev->p->async_driver = drv; | |
c37e20ea | 1069 | async_schedule_dev(__driver_attach_async_helper, dev); |
ef0ff683 AD |
1070 | } |
1071 | device_unlock(dev); | |
1072 | return 0; | |
1073 | } | |
1074 | ||
ed88747c | 1075 | device_driver_attach(drv, dev); |
0d3e5a2e | 1076 | |
07e4a3e2 PM |
1077 | return 0; |
1078 | } | |
1079 | ||
1080 | /** | |
4a3ad20c GKH |
1081 | * driver_attach - try to bind driver to devices. |
1082 | * @drv: driver. | |
07e4a3e2 | 1083 | * |
4a3ad20c GKH |
1084 | * Walk the list of devices that the bus has on it and try to |
1085 | * match the driver with each one. If driver_probe_device() | |
1086 | * returns 0 and the @dev->driver is set, we've found a | |
1087 | * compatible pair. | |
07e4a3e2 | 1088 | */ |
4a3ad20c | 1089 | int driver_attach(struct device_driver *drv) |
07e4a3e2 | 1090 | { |
f86db396 | 1091 | return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach); |
07e4a3e2 | 1092 | } |
4a3ad20c | 1093 | EXPORT_SYMBOL_GPL(driver_attach); |
07e4a3e2 | 1094 | |
ab71c6f0 | 1095 | /* |
8e9394ce GKH |
1096 | * __device_release_driver() must be called with @dev lock held. |
1097 | * When called for a USB interface, @dev->parent lock must be held as well. | |
07e4a3e2 | 1098 | */ |
9ed98953 | 1099 | static void __device_release_driver(struct device *dev, struct device *parent) |
07e4a3e2 | 1100 | { |
4a3ad20c | 1101 | struct device_driver *drv; |
07e4a3e2 | 1102 | |
ef2c5174 | 1103 | drv = dev->driver; |
c95a6b05 | 1104 | if (drv) { |
9ed98953 | 1105 | while (device_links_busy(dev)) { |
ed88747c | 1106 | __device_driver_unlock(dev, parent); |
9ed98953 RW |
1107 | |
1108 | device_links_unbind_consumers(dev); | |
9ed98953 | 1109 | |
ed88747c | 1110 | __device_driver_lock(dev, parent); |
9ed98953 RW |
1111 | /* |
1112 | * A concurrent invocation of the same function might | |
1113 | * have released the driver successfully while this one | |
1114 | * was waiting, so check for that. | |
1115 | */ | |
1116 | if (dev->driver != drv) | |
1117 | return; | |
1118 | } | |
1119 | ||
e1866b33 | 1120 | pm_runtime_get_sync(dev); |
21d5c57b | 1121 | pm_runtime_clean_up_links(dev); |
5e928f77 | 1122 | |
1901fb26 | 1123 | driver_sysfs_remove(dev); |
0d3e5a2e | 1124 | |
116af378 | 1125 | if (dev->bus) |
c6f7e72a | 1126 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
116af378 BH |
1127 | BUS_NOTIFY_UNBIND_DRIVER, |
1128 | dev); | |
1129 | ||
baab52de | 1130 | pm_runtime_put_sync(dev); |
e1866b33 | 1131 | |
23b69044 DT |
1132 | device_remove_groups(dev, drv->dev_groups); |
1133 | ||
0f836ca4 | 1134 | if (dev->bus && dev->bus->remove) |
594c8281 RK |
1135 | dev->bus->remove(dev); |
1136 | else if (drv->remove) | |
0d3e5a2e | 1137 | drv->remove(dev); |
9ed98953 RW |
1138 | |
1139 | device_links_driver_cleanup(dev); | |
09515ef5 | 1140 | |
9ac7849e | 1141 | devres_release_all(dev); |
376991db | 1142 | arch_teardown_dma_ops(dev); |
0d3e5a2e | 1143 | dev->driver = NULL; |
0998d063 | 1144 | dev_set_drvdata(dev, NULL); |
e90d5532 RW |
1145 | if (dev->pm_domain && dev->pm_domain->dismiss) |
1146 | dev->pm_domain->dismiss(dev); | |
5de85b9d | 1147 | pm_runtime_reinit(dev); |
08810a41 | 1148 | dev_pm_set_driver_flags(dev, 0); |
e90d5532 | 1149 | |
8940b4f3 | 1150 | klist_remove(&dev->p->knode_driver); |
aa8e54b5 | 1151 | device_pm_check_callbacks(dev); |
309b7d60 JR |
1152 | if (dev->bus) |
1153 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
1154 | BUS_NOTIFY_UNBOUND_DRIVER, | |
1155 | dev); | |
1455cf8d DT |
1156 | |
1157 | kobject_uevent(&dev->kobj, KOBJ_UNBIND); | |
0d3e5a2e | 1158 | } |
07e4a3e2 PM |
1159 | } |
1160 | ||
9ed98953 RW |
1161 | void device_release_driver_internal(struct device *dev, |
1162 | struct device_driver *drv, | |
1163 | struct device *parent) | |
4bdb3550 | 1164 | { |
ed88747c | 1165 | __device_driver_lock(dev, parent); |
4bdb3550 | 1166 | |
4bdb3550 | 1167 | if (!drv || drv == dev->driver) |
9ed98953 | 1168 | __device_release_driver(dev, parent); |
4bdb3550 | 1169 | |
ed88747c | 1170 | __device_driver_unlock(dev, parent); |
4bdb3550 RW |
1171 | } |
1172 | ||
ab71c6f0 | 1173 | /** |
4a3ad20c GKH |
1174 | * device_release_driver - manually detach device from driver. |
1175 | * @dev: device. | |
ab71c6f0 | 1176 | * |
4a3ad20c | 1177 | * Manually detach device from driver. |
8e9394ce | 1178 | * When called for a USB interface, @dev->parent lock must be held. |
9ed98953 RW |
1179 | * |
1180 | * If this function is to be called with @dev->parent lock held, ensure that | |
1181 | * the device's consumers are unbound in advance or that their locks can be | |
1182 | * acquired under the @dev->parent lock. | |
ab71c6f0 | 1183 | */ |
4a3ad20c | 1184 | void device_release_driver(struct device *dev) |
94e7b1c5 | 1185 | { |
c95a6b05 AS |
1186 | /* |
1187 | * If anyone calls device_release_driver() recursively from | |
1188 | * within their ->remove callback for the same device, they | |
1189 | * will deadlock right here. | |
1190 | */ | |
4bdb3550 | 1191 | device_release_driver_internal(dev, NULL, NULL); |
94e7b1c5 | 1192 | } |
4a3ad20c | 1193 | EXPORT_SYMBOL_GPL(device_release_driver); |
c95a6b05 | 1194 | |
ed88747c AD |
1195 | /** |
1196 | * device_driver_detach - detach driver from a specific device | |
1197 | * @dev: device to detach driver from | |
1198 | * | |
1199 | * Detach driver from device. Will acquire both @dev lock and @dev->parent | |
1200 | * lock if needed. | |
1201 | */ | |
1202 | void device_driver_detach(struct device *dev) | |
1203 | { | |
1204 | device_release_driver_internal(dev, NULL, dev->parent); | |
1205 | } | |
1206 | ||
07e4a3e2 PM |
1207 | /** |
1208 | * driver_detach - detach driver from all devices it controls. | |
1209 | * @drv: driver. | |
1210 | */ | |
4a3ad20c | 1211 | void driver_detach(struct device_driver *drv) |
07e4a3e2 | 1212 | { |
8940b4f3 | 1213 | struct device_private *dev_prv; |
4a3ad20c | 1214 | struct device *dev; |
c95a6b05 | 1215 | |
c37d721c AD |
1216 | if (driver_allows_async_probing(drv)) |
1217 | async_synchronize_full(); | |
1218 | ||
c95a6b05 | 1219 | for (;;) { |
e5dd1278 GKH |
1220 | spin_lock(&drv->p->klist_devices.k_lock); |
1221 | if (list_empty(&drv->p->klist_devices.k_list)) { | |
1222 | spin_unlock(&drv->p->klist_devices.k_lock); | |
c95a6b05 AS |
1223 | break; |
1224 | } | |
8940b4f3 GKH |
1225 | dev_prv = list_entry(drv->p->klist_devices.k_list.prev, |
1226 | struct device_private, | |
1227 | knode_driver.n_node); | |
1228 | dev = dev_prv->device; | |
c95a6b05 | 1229 | get_device(dev); |
e5dd1278 | 1230 | spin_unlock(&drv->p->klist_devices.k_lock); |
4bdb3550 | 1231 | device_release_driver_internal(dev, drv, dev->parent); |
c95a6b05 AS |
1232 | put_device(dev); |
1233 | } | |
07e4a3e2 | 1234 | } |