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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 | 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 | 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) | |
716a7a25 SK |
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 | ||
ce68929f | 227 | int driver_deferred_probe_timeout; |
64c775fb | 228 | EXPORT_SYMBOL_GPL(driver_deferred_probe_timeout); |
35a67236 | 229 | static DECLARE_WAIT_QUEUE_HEAD(probe_timeout_waitqueue); |
64c775fb | 230 | |
25b4e70d RH |
231 | static int __init deferred_probe_timeout_setup(char *str) |
232 | { | |
63c98047 MS |
233 | int timeout; |
234 | ||
235 | if (!kstrtoint(str, 10, &timeout)) | |
64c775fb | 236 | driver_deferred_probe_timeout = timeout; |
25b4e70d RH |
237 | return 1; |
238 | } | |
239 | __setup("deferred_probe_timeout=", deferred_probe_timeout_setup); | |
240 | ||
241 | /** | |
242 | * driver_deferred_probe_check_state() - Check deferred probe state | |
243 | * @dev: device to check | |
244 | * | |
c8c43cee JS |
245 | * Return: |
246 | * -ENODEV if initcalls have completed and modules are disabled. | |
247 | * -ETIMEDOUT if the deferred probe timeout was set and has expired | |
248 | * and modules are enabled. | |
249 | * -EPROBE_DEFER in other cases. | |
25b4e70d RH |
250 | * |
251 | * Drivers or subsystems can opt-in to calling this function instead of directly | |
252 | * returning -EPROBE_DEFER. | |
253 | */ | |
254 | int driver_deferred_probe_check_state(struct device *dev) | |
255 | { | |
0e9f8d09 | 256 | if (!IS_ENABLED(CONFIG_MODULES) && initcalls_done) { |
eb7fbc9f | 257 | dev_warn(dev, "ignoring dependency for device, assuming no driver\n"); |
0e9f8d09 JS |
258 | return -ENODEV; |
259 | } | |
62a6bc3a | 260 | |
ce68929f | 261 | if (!driver_deferred_probe_timeout && initcalls_done) { |
c8be6af9 | 262 | dev_warn(dev, "deferred probe timeout, ignoring dependency\n"); |
0e9f8d09 JS |
263 | return -ETIMEDOUT; |
264 | } | |
62a6bc3a | 265 | |
25b4e70d RH |
266 | return -EPROBE_DEFER; |
267 | } | |
268 | ||
269 | static void deferred_probe_timeout_work_func(struct work_struct *work) | |
270 | { | |
271 | struct device_private *private, *p; | |
272 | ||
64c775fb | 273 | driver_deferred_probe_timeout = 0; |
25b4e70d RH |
274 | driver_deferred_probe_trigger(); |
275 | flush_work(&deferred_probe_work); | |
276 | ||
277 | list_for_each_entry_safe(private, p, &deferred_probe_pending_list, deferred_probe) | |
eb7fbc9f | 278 | dev_info(private->device, "deferred probe pending\n"); |
35a67236 | 279 | wake_up(&probe_timeout_waitqueue); |
25b4e70d RH |
280 | } |
281 | static DECLARE_DELAYED_WORK(deferred_probe_timeout_work, deferred_probe_timeout_work_func); | |
282 | ||
d1c3414c GL |
283 | /** |
284 | * deferred_probe_initcall() - Enable probing of deferred devices | |
285 | * | |
286 | * We don't want to get in the way when the bulk of drivers are getting probed. | |
287 | * Instead, this initcall makes sure that deferred probing is delayed until | |
288 | * late_initcall time. | |
289 | */ | |
290 | static int deferred_probe_initcall(void) | |
291 | { | |
28af109a JMC |
292 | deferred_devices = debugfs_create_file("devices_deferred", 0444, NULL, |
293 | NULL, &deferred_devs_fops); | |
294 | ||
d1c3414c GL |
295 | driver_deferred_probe_enable = true; |
296 | driver_deferred_probe_trigger(); | |
d72cca1e | 297 | /* Sort as many dependencies as possible before exiting initcalls */ |
2c507e46 | 298 | flush_work(&deferred_probe_work); |
25b4e70d RH |
299 | initcalls_done = true; |
300 | ||
301 | /* | |
302 | * Trigger deferred probe again, this time we won't defer anything | |
303 | * that is optional | |
304 | */ | |
305 | driver_deferred_probe_trigger(); | |
306 | flush_work(&deferred_probe_work); | |
307 | ||
64c775fb | 308 | if (driver_deferred_probe_timeout > 0) { |
25b4e70d | 309 | schedule_delayed_work(&deferred_probe_timeout_work, |
64c775fb | 310 | driver_deferred_probe_timeout * HZ); |
25b4e70d | 311 | } |
d1c3414c GL |
312 | return 0; |
313 | } | |
314 | late_initcall(deferred_probe_initcall); | |
07e4a3e2 | 315 | |
28af109a JMC |
316 | static void __exit deferred_probe_exit(void) |
317 | { | |
318 | debugfs_remove_recursive(deferred_devices); | |
319 | } | |
320 | __exitcall(deferred_probe_exit); | |
321 | ||
6b9cb427 TV |
322 | /** |
323 | * device_is_bound() - Check if device is bound to a driver | |
324 | * @dev: device to check | |
325 | * | |
326 | * Returns true if passed device has already finished probing successfully | |
327 | * against a driver. | |
328 | * | |
329 | * This function must be called with the device lock held. | |
330 | */ | |
331 | bool device_is_bound(struct device *dev) | |
332 | { | |
3ded9104 | 333 | return dev->p && klist_node_attached(&dev->p->knode_driver); |
6b9cb427 TV |
334 | } |
335 | ||
1901fb26 | 336 | static void driver_bound(struct device *dev) |
07e4a3e2 | 337 | { |
6b9cb427 | 338 | if (device_is_bound(dev)) { |
eb7fbc9f | 339 | pr_warn("%s: device %s already bound\n", |
2b3a302a | 340 | __func__, kobject_name(&dev->kobj)); |
1901fb26 | 341 | return; |
f86db396 | 342 | } |
4c898c7f | 343 | |
94f8cc0e FR |
344 | pr_debug("driver: '%s': %s: bound to device '%s'\n", dev->driver->name, |
345 | __func__, dev_name(dev)); | |
116af378 | 346 | |
fbb88fad | 347 | klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices); |
9ed98953 | 348 | device_links_driver_bound(dev); |
fbb88fad | 349 | |
aa8e54b5 TV |
350 | device_pm_check_callbacks(dev); |
351 | ||
8b0372a2 GKH |
352 | /* |
353 | * Make sure the device is no longer in one of the deferred lists and | |
354 | * kick off retrying all pending devices | |
355 | */ | |
d1c3414c GL |
356 | driver_deferred_probe_del(dev); |
357 | driver_deferred_probe_trigger(); | |
358 | ||
116af378 | 359 | if (dev->bus) |
c6f7e72a | 360 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
116af378 | 361 | BUS_NOTIFY_BOUND_DRIVER, dev); |
1455cf8d DT |
362 | |
363 | kobject_uevent(&dev->kobj, KOBJ_BIND); | |
1901fb26 KS |
364 | } |
365 | ||
3c47d19f AS |
366 | static ssize_t coredump_store(struct device *dev, struct device_attribute *attr, |
367 | const char *buf, size_t count) | |
368 | { | |
369 | device_lock(dev); | |
1fe56e0c | 370 | dev->driver->coredump(dev); |
3c47d19f AS |
371 | device_unlock(dev); |
372 | ||
373 | return count; | |
374 | } | |
375 | static DEVICE_ATTR_WO(coredump); | |
376 | ||
1901fb26 KS |
377 | static int driver_sysfs_add(struct device *dev) |
378 | { | |
379 | int ret; | |
380 | ||
45daef0f MD |
381 | if (dev->bus) |
382 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
383 | BUS_NOTIFY_BIND_DRIVER, dev); | |
384 | ||
e5dd1278 | 385 | ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj, |
3c47d19f AS |
386 | kobject_name(&dev->kobj)); |
387 | if (ret) | |
388 | goto fail; | |
389 | ||
390 | ret = sysfs_create_link(&dev->kobj, &dev->driver->p->kobj, | |
391 | "driver"); | |
392 | if (ret) | |
393 | goto rm_dev; | |
394 | ||
395 | if (!IS_ENABLED(CONFIG_DEV_COREDUMP) || !dev->driver->coredump || | |
396 | !device_create_file(dev, &dev_attr_coredump)) | |
397 | return 0; | |
398 | ||
399 | sysfs_remove_link(&dev->kobj, "driver"); | |
400 | ||
401 | rm_dev: | |
402 | sysfs_remove_link(&dev->driver->p->kobj, | |
07e4a3e2 | 403 | kobject_name(&dev->kobj)); |
3c47d19f AS |
404 | |
405 | fail: | |
f86db396 | 406 | return ret; |
07e4a3e2 | 407 | } |
408 | ||
1901fb26 KS |
409 | static void driver_sysfs_remove(struct device *dev) |
410 | { | |
411 | struct device_driver *drv = dev->driver; | |
412 | ||
413 | if (drv) { | |
3c47d19f AS |
414 | if (drv->coredump) |
415 | device_remove_file(dev, &dev_attr_coredump); | |
e5dd1278 | 416 | sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj)); |
1901fb26 KS |
417 | sysfs_remove_link(&dev->kobj, "driver"); |
418 | } | |
419 | } | |
420 | ||
421 | /** | |
4a3ad20c GKH |
422 | * device_bind_driver - bind a driver to one device. |
423 | * @dev: device. | |
1901fb26 | 424 | * |
4a3ad20c GKH |
425 | * Allow manual attachment of a driver to a device. |
426 | * Caller must have already set @dev->driver. | |
1901fb26 | 427 | * |
fe940d73 LW |
428 | * Note that this does not modify the bus reference count. |
429 | * Please verify that is accounted for before calling this. | |
430 | * (It is ok to call with no other effort from a driver's probe() method.) | |
1901fb26 | 431 | * |
8e9394ce | 432 | * This function must be called with the device lock held. |
1901fb26 KS |
433 | */ |
434 | int device_bind_driver(struct device *dev) | |
435 | { | |
cb986b74 CH |
436 | int ret; |
437 | ||
438 | ret = driver_sysfs_add(dev); | |
439 | if (!ret) | |
440 | driver_bound(dev); | |
14b6257a AS |
441 | else if (dev->bus) |
442 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
443 | BUS_NOTIFY_DRIVER_NOT_BOUND, dev); | |
cb986b74 | 444 | return ret; |
1901fb26 | 445 | } |
4a3ad20c | 446 | EXPORT_SYMBOL_GPL(device_bind_driver); |
1901fb26 | 447 | |
d779249e | 448 | static atomic_t probe_count = ATOMIC_INIT(0); |
735a7ffb AM |
449 | static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue); |
450 | ||
0ff26c66 AH |
451 | static void driver_deferred_probe_add_trigger(struct device *dev, |
452 | int local_trigger_count) | |
453 | { | |
454 | driver_deferred_probe_add(dev); | |
455 | /* Did a trigger occur while probing? Need to re-trigger if yes */ | |
456 | if (local_trigger_count != atomic_read(&deferred_trigger_count)) | |
457 | driver_deferred_probe_trigger(); | |
458 | } | |
459 | ||
8fd456ec SK |
460 | static ssize_t state_synced_show(struct device *dev, |
461 | struct device_attribute *attr, char *buf) | |
462 | { | |
463 | bool val; | |
464 | ||
465 | device_lock(dev); | |
466 | val = dev->state_synced; | |
467 | device_unlock(dev); | |
468 | return sprintf(buf, "%u\n", val); | |
469 | } | |
470 | static DEVICE_ATTR_RO(state_synced); | |
471 | ||
21c7f30b | 472 | static int really_probe(struct device *dev, struct device_driver *drv) |
07e4a3e2 | 473 | { |
013c074f | 474 | int ret = -EPROBE_DEFER; |
58b116bc | 475 | int local_trigger_count = atomic_read(&deferred_trigger_count); |
c5f06274 RH |
476 | bool test_remove = IS_ENABLED(CONFIG_DEBUG_TEST_DRIVER_REMOVE) && |
477 | !drv->suppress_bind_attrs; | |
07e4a3e2 | 478 | |
013c074f SG |
479 | if (defer_all_probes) { |
480 | /* | |
481 | * Value of defer_all_probes can be set only by | |
dbf03d65 | 482 | * device_block_probing() which, in turn, will call |
013c074f SG |
483 | * wait_for_device_probe() right after that to avoid any races. |
484 | */ | |
485 | dev_dbg(dev, "Driver %s force probe deferral\n", drv->name); | |
486 | driver_deferred_probe_add(dev); | |
487 | return ret; | |
488 | } | |
489 | ||
9ed98953 | 490 | ret = device_links_check_suppliers(dev); |
0ff26c66 AH |
491 | if (ret == -EPROBE_DEFER) |
492 | driver_deferred_probe_add_trigger(dev, local_trigger_count); | |
9ed98953 RW |
493 | if (ret) |
494 | return ret; | |
495 | ||
d779249e | 496 | atomic_inc(&probe_count); |
7dc72b28 | 497 | pr_debug("bus: '%s': %s: probing driver %s with device %s\n", |
1e0b2cf9 | 498 | drv->bus->name, __func__, drv->name, dev_name(dev)); |
7c35e699 GU |
499 | if (!list_empty(&dev->devres_head)) { |
500 | dev_crit(dev, "Resources present before probing\n"); | |
501 | return -EBUSY; | |
502 | } | |
07e4a3e2 | 503 | |
bea5b158 | 504 | re_probe: |
07e4a3e2 | 505 | dev->driver = drv; |
ab78029e LW |
506 | |
507 | /* If using pinctrl, bind pins now before probing */ | |
508 | ret = pinctrl_bind_pins(dev); | |
509 | if (ret) | |
14b6257a | 510 | goto pinctrl_bind_failed; |
ab78029e | 511 | |
ccf640f4 CH |
512 | if (dev->bus->dma_configure) { |
513 | ret = dev->bus->dma_configure(dev); | |
514 | if (ret) | |
0b777eee | 515 | goto probe_failed; |
ccf640f4 | 516 | } |
09515ef5 | 517 | |
1901fb26 | 518 | if (driver_sysfs_add(dev)) { |
eb7fbc9f CJ |
519 | pr_err("%s: driver_sysfs_add(%s) failed\n", |
520 | __func__, dev_name(dev)); | |
1901fb26 KS |
521 | goto probe_failed; |
522 | } | |
523 | ||
e90d5532 RW |
524 | if (dev->pm_domain && dev->pm_domain->activate) { |
525 | ret = dev->pm_domain->activate(dev); | |
526 | if (ret) | |
527 | goto probe_failed; | |
528 | } | |
529 | ||
594c8281 RK |
530 | if (dev->bus->probe) { |
531 | ret = dev->bus->probe(dev); | |
1901fb26 | 532 | if (ret) |
d779249e | 533 | goto probe_failed; |
594c8281 | 534 | } else if (drv->probe) { |
0d3e5a2e | 535 | ret = drv->probe(dev); |
1901fb26 | 536 | if (ret) |
d779249e | 537 | goto probe_failed; |
f86db396 | 538 | } |
1901fb26 | 539 | |
23b69044 DT |
540 | if (device_add_groups(dev, drv->dev_groups)) { |
541 | dev_err(dev, "device_add_groups() failed\n"); | |
542 | goto dev_groups_failed; | |
543 | } | |
544 | ||
8fd456ec SK |
545 | if (dev_has_sync_state(dev) && |
546 | device_create_file(dev, &dev_attr_state_synced)) { | |
547 | dev_err(dev, "state_synced sysfs add failed\n"); | |
548 | goto dev_sysfs_state_synced_failed; | |
549 | } | |
550 | ||
bea5b158 RH |
551 | if (test_remove) { |
552 | test_remove = false; | |
553 | ||
8fd456ec | 554 | device_remove_file(dev, &dev_attr_state_synced); |
23b69044 DT |
555 | device_remove_groups(dev, drv->dev_groups); |
556 | ||
bdacd1b4 | 557 | if (dev->bus->remove) |
bea5b158 RH |
558 | dev->bus->remove(dev); |
559 | else if (drv->remove) | |
560 | drv->remove(dev); | |
561 | ||
562 | devres_release_all(dev); | |
563 | driver_sysfs_remove(dev); | |
564 | dev->driver = NULL; | |
565 | dev_set_drvdata(dev, NULL); | |
566 | if (dev->pm_domain && dev->pm_domain->dismiss) | |
567 | dev->pm_domain->dismiss(dev); | |
568 | pm_runtime_reinit(dev); | |
569 | ||
570 | goto re_probe; | |
571 | } | |
572 | ||
ef0eebc0 DA |
573 | pinctrl_init_done(dev); |
574 | ||
e90d5532 RW |
575 | if (dev->pm_domain && dev->pm_domain->sync) |
576 | dev->pm_domain->sync(dev); | |
577 | ||
1901fb26 | 578 | driver_bound(dev); |
0d3e5a2e | 579 | ret = 1; |
7dc72b28 | 580 | pr_debug("bus: '%s': %s: bound device %s to driver %s\n", |
1e0b2cf9 | 581 | drv->bus->name, __func__, dev_name(dev), drv->name); |
d779249e | 582 | goto done; |
0d3e5a2e | 583 | |
8fd456ec SK |
584 | dev_sysfs_state_synced_failed: |
585 | device_remove_groups(dev, drv->dev_groups); | |
23b69044 DT |
586 | dev_groups_failed: |
587 | if (dev->bus->remove) | |
588 | dev->bus->remove(dev); | |
589 | else if (drv->remove) | |
590 | drv->remove(dev); | |
d779249e | 591 | probe_failed: |
14b6257a AS |
592 | if (dev->bus) |
593 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
594 | BUS_NOTIFY_DRIVER_NOT_BOUND, dev); | |
595 | pinctrl_bind_failed: | |
9ed98953 | 596 | device_links_no_driver(dev); |
9ac7849e | 597 | devres_release_all(dev); |
0b777eee | 598 | arch_teardown_dma_ops(dev); |
1901fb26 KS |
599 | driver_sysfs_remove(dev); |
600 | dev->driver = NULL; | |
0998d063 | 601 | dev_set_drvdata(dev, NULL); |
e90d5532 RW |
602 | if (dev->pm_domain && dev->pm_domain->dismiss) |
603 | dev->pm_domain->dismiss(dev); | |
5de85b9d | 604 | pm_runtime_reinit(dev); |
08810a41 | 605 | dev_pm_set_driver_flags(dev, 0); |
1901fb26 | 606 | |
bb2b4075 SS |
607 | switch (ret) { |
608 | case -EPROBE_DEFER: | |
d1c3414c | 609 | /* Driver requested deferred probing */ |
13fcffbb | 610 | dev_dbg(dev, "Driver %s requests probe deferral\n", drv->name); |
0ff26c66 | 611 | driver_deferred_probe_add_trigger(dev, local_trigger_count); |
bb2b4075 SS |
612 | break; |
613 | case -ENODEV: | |
614 | case -ENXIO: | |
615 | pr_debug("%s: probe of %s rejects match %d\n", | |
616 | drv->name, dev_name(dev), ret); | |
617 | break; | |
618 | default: | |
0d3e5a2e | 619 | /* driver matched but the probe failed */ |
eb7fbc9f CJ |
620 | pr_warn("%s: probe of %s failed with error %d\n", |
621 | drv->name, dev_name(dev), ret); | |
0d3e5a2e | 622 | } |
c578abbc CH |
623 | /* |
624 | * Ignore errors returned by ->probe so that the next driver can try | |
625 | * its luck. | |
626 | */ | |
627 | ret = 0; | |
d779249e | 628 | done: |
d779249e | 629 | atomic_dec(&probe_count); |
735a7ffb | 630 | wake_up(&probe_waitqueue); |
d779249e GKH |
631 | return ret; |
632 | } | |
633 | ||
0a50f61c TP |
634 | /* |
635 | * For initcall_debug, show the driver probe time. | |
636 | */ | |
637 | static int really_probe_debug(struct device *dev, struct device_driver *drv) | |
638 | { | |
639 | ktime_t calltime, delta, rettime; | |
640 | int ret; | |
641 | ||
642 | calltime = ktime_get(); | |
643 | ret = really_probe(dev, drv); | |
644 | rettime = ktime_get(); | |
645 | delta = ktime_sub(rettime, calltime); | |
eb7fbc9f CJ |
646 | pr_debug("probe of %s returned %d after %lld usecs\n", |
647 | dev_name(dev), ret, (s64) ktime_to_us(delta)); | |
0a50f61c TP |
648 | return ret; |
649 | } | |
650 | ||
d779249e GKH |
651 | /** |
652 | * driver_probe_done | |
653 | * Determine if the probe sequence is finished or not. | |
654 | * | |
655 | * Should somehow figure out how to use a semaphore, not an atomic variable... | |
656 | */ | |
657 | int driver_probe_done(void) | |
658 | { | |
927f8287 AS |
659 | int local_probe_count = atomic_read(&probe_count); |
660 | ||
661 | pr_debug("%s: probe_count = %d\n", __func__, local_probe_count); | |
662 | if (local_probe_count) | |
d779249e GKH |
663 | return -EBUSY; |
664 | return 0; | |
665 | } | |
666 | ||
216773a7 AV |
667 | /** |
668 | * wait_for_device_probe | |
669 | * Wait for device probing to be completed. | |
216773a7 | 670 | */ |
b23530eb | 671 | void wait_for_device_probe(void) |
216773a7 | 672 | { |
35a67236 JS |
673 | /* wait for probe timeout */ |
674 | wait_event(probe_timeout_waitqueue, !driver_deferred_probe_timeout); | |
675 | ||
013c074f | 676 | /* wait for the deferred probe workqueue to finish */ |
2c507e46 | 677 | flush_work(&deferred_probe_work); |
013c074f | 678 | |
216773a7 | 679 | /* wait for the known devices to complete their probing */ |
b23530eb | 680 | wait_event(probe_waitqueue, atomic_read(&probe_count) == 0); |
216773a7 | 681 | async_synchronize_full(); |
216773a7 | 682 | } |
d4d5291c | 683 | EXPORT_SYMBOL_GPL(wait_for_device_probe); |
216773a7 | 684 | |
d779249e GKH |
685 | /** |
686 | * driver_probe_device - attempt to bind device & driver together | |
687 | * @drv: driver to bind a device to | |
688 | * @dev: device to try to bind to the driver | |
689 | * | |
49b420a1 | 690 | * This function returns -ENODEV if the device is not registered, |
af901ca1 | 691 | * 1 if the device is bound successfully and 0 otherwise. |
d779249e | 692 | * |
8e9394ce GKH |
693 | * This function must be called with @dev lock held. When called for a |
694 | * USB interface, @dev->parent lock must be held as well. | |
ddef08dd RW |
695 | * |
696 | * If the device has a parent, runtime-resume the parent before driver probing. | |
d779249e | 697 | */ |
4a3ad20c | 698 | int driver_probe_device(struct device_driver *drv, struct device *dev) |
d779249e | 699 | { |
d779249e GKH |
700 | int ret = 0; |
701 | ||
f2eaae19 AS |
702 | if (!device_is_registered(dev)) |
703 | return -ENODEV; | |
d779249e | 704 | |
7dc72b28 | 705 | pr_debug("bus: '%s': %s: matched device %s with driver %s\n", |
1e0b2cf9 | 706 | drv->bus->name, __func__, dev_name(dev), drv->name); |
d779249e | 707 | |
b06c0b2f | 708 | pm_runtime_get_suppliers(dev); |
ddef08dd RW |
709 | if (dev->parent) |
710 | pm_runtime_get_sync(dev->parent); | |
711 | ||
5e928f77 | 712 | pm_runtime_barrier(dev); |
0a50f61c TP |
713 | if (initcall_debug) |
714 | ret = really_probe_debug(dev, drv); | |
715 | else | |
716 | ret = really_probe(dev, drv); | |
fa180eb4 | 717 | pm_request_idle(dev); |
d779249e | 718 | |
ddef08dd RW |
719 | if (dev->parent) |
720 | pm_runtime_put(dev->parent); | |
721 | ||
b06c0b2f | 722 | pm_runtime_put_suppliers(dev); |
0d3e5a2e | 723 | return ret; |
07e4a3e2 | 724 | } |
725 | ||
1ea61b68 FT |
726 | static inline bool cmdline_requested_async_probing(const char *drv_name) |
727 | { | |
728 | return parse_option_str(async_probe_drv_names, drv_name); | |
729 | } | |
730 | ||
731 | /* The option format is "driver_async_probe=drv_name1,drv_name2,..." */ | |
732 | static int __init save_async_options(char *buf) | |
733 | { | |
734 | if (strlen(buf) >= ASYNC_DRV_NAMES_MAX_LEN) | |
eb7fbc9f | 735 | pr_warn("Too long list of driver names for 'driver_async_probe'!\n"); |
1ea61b68 FT |
736 | |
737 | strlcpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN); | |
738 | return 0; | |
739 | } | |
740 | __setup("driver_async_probe=", save_async_options); | |
741 | ||
765230b5 | 742 | bool driver_allows_async_probing(struct device_driver *drv) |
2287c322 | 743 | { |
d173a137 LR |
744 | switch (drv->probe_type) { |
745 | case PROBE_PREFER_ASYNCHRONOUS: | |
f2411da7 LR |
746 | return true; |
747 | ||
d173a137 LR |
748 | case PROBE_FORCE_SYNCHRONOUS: |
749 | return false; | |
750 | ||
751 | default: | |
1ea61b68 FT |
752 | if (cmdline_requested_async_probing(drv->name)) |
753 | return true; | |
754 | ||
80c6e146 | 755 | if (module_requested_async_probing(drv->owner)) |
d173a137 | 756 | return true; |
f2411da7 | 757 | |
d173a137 LR |
758 | return false; |
759 | } | |
765230b5 DT |
760 | } |
761 | ||
762 | struct device_attach_data { | |
763 | struct device *dev; | |
764 | ||
765 | /* | |
766 | * Indicates whether we are are considering asynchronous probing or | |
767 | * not. Only initial binding after device or driver registration | |
768 | * (including deferral processing) may be done asynchronously, the | |
769 | * rest is always synchronous, as we expect it is being done by | |
770 | * request from userspace. | |
771 | */ | |
772 | bool check_async; | |
773 | ||
774 | /* | |
775 | * Indicates if we are binding synchronous or asynchronous drivers. | |
776 | * When asynchronous probing is enabled we'll execute 2 passes | |
777 | * over drivers: first pass doing synchronous probing and second | |
778 | * doing asynchronous probing (if synchronous did not succeed - | |
779 | * most likely because there was no driver requiring synchronous | |
780 | * probing - and we found asynchronous driver during first pass). | |
781 | * The 2 passes are done because we can't shoot asynchronous | |
782 | * probe for given device and driver from bus_for_each_drv() since | |
783 | * driver pointer is not guaranteed to stay valid once | |
784 | * bus_for_each_drv() iterates to the next driver on the bus. | |
785 | */ | |
786 | bool want_async; | |
787 | ||
788 | /* | |
789 | * We'll set have_async to 'true' if, while scanning for matching | |
790 | * driver, we'll encounter one that requests asynchronous probing. | |
791 | */ | |
792 | bool have_async; | |
793 | }; | |
794 | ||
795 | static int __device_attach_driver(struct device_driver *drv, void *_data) | |
796 | { | |
797 | struct device_attach_data *data = _data; | |
798 | struct device *dev = data->dev; | |
799 | bool async_allowed; | |
656b8035 | 800 | int ret; |
765230b5 | 801 | |
656b8035 TV |
802 | ret = driver_match_device(drv, dev); |
803 | if (ret == 0) { | |
804 | /* no match */ | |
49b420a1 | 805 | return 0; |
656b8035 TV |
806 | } else if (ret == -EPROBE_DEFER) { |
807 | dev_dbg(dev, "Device match requests probe deferral\n"); | |
808 | driver_deferred_probe_add(dev); | |
809 | } else if (ret < 0) { | |
eb7fbc9f | 810 | dev_dbg(dev, "Bus failed to match device: %d\n", ret); |
656b8035 TV |
811 | return ret; |
812 | } /* ret > 0 means positive match */ | |
49b420a1 | 813 | |
765230b5 DT |
814 | async_allowed = driver_allows_async_probing(drv); |
815 | ||
816 | if (async_allowed) | |
817 | data->have_async = true; | |
818 | ||
819 | if (data->check_async && async_allowed != data->want_async) | |
820 | return 0; | |
821 | ||
0d3e5a2e | 822 | return driver_probe_device(drv, dev); |
2287c322 | 823 | } |
824 | ||
765230b5 DT |
825 | static void __device_attach_async_helper(void *_dev, async_cookie_t cookie) |
826 | { | |
827 | struct device *dev = _dev; | |
828 | struct device_attach_data data = { | |
829 | .dev = dev, | |
830 | .check_async = true, | |
831 | .want_async = true, | |
832 | }; | |
833 | ||
834 | device_lock(dev); | |
835 | ||
3451a495 AD |
836 | /* |
837 | * Check if device has already been removed or claimed. This may | |
838 | * happen with driver loading, device discovery/registration, | |
839 | * and deferred probe processing happens all at once with | |
840 | * multiple threads. | |
841 | */ | |
842 | if (dev->p->dead || dev->driver) | |
843 | goto out_unlock; | |
844 | ||
ddef08dd RW |
845 | if (dev->parent) |
846 | pm_runtime_get_sync(dev->parent); | |
847 | ||
765230b5 DT |
848 | bus_for_each_drv(dev->bus, NULL, &data, __device_attach_driver); |
849 | dev_dbg(dev, "async probe completed\n"); | |
850 | ||
851 | pm_request_idle(dev); | |
852 | ||
ddef08dd RW |
853 | if (dev->parent) |
854 | pm_runtime_put(dev->parent); | |
3451a495 | 855 | out_unlock: |
765230b5 DT |
856 | device_unlock(dev); |
857 | ||
858 | put_device(dev); | |
859 | } | |
860 | ||
802a87fd | 861 | static int __device_attach(struct device *dev, bool allow_async) |
07e4a3e2 | 862 | { |
0d3e5a2e PM |
863 | int ret = 0; |
864 | ||
8e9394ce | 865 | device_lock(dev); |
07e4a3e2 | 866 | if (dev->driver) { |
6b9cb427 | 867 | if (device_is_bound(dev)) { |
8497d6a2 SO |
868 | ret = 1; |
869 | goto out_unlock; | |
870 | } | |
f86db396 AM |
871 | ret = device_bind_driver(dev); |
872 | if (ret == 0) | |
873 | ret = 1; | |
c6a46696 CH |
874 | else { |
875 | dev->driver = NULL; | |
876 | ret = 0; | |
877 | } | |
21c7f30b | 878 | } else { |
765230b5 DT |
879 | struct device_attach_data data = { |
880 | .dev = dev, | |
881 | .check_async = allow_async, | |
882 | .want_async = false, | |
883 | }; | |
884 | ||
ddef08dd RW |
885 | if (dev->parent) |
886 | pm_runtime_get_sync(dev->parent); | |
887 | ||
765230b5 DT |
888 | ret = bus_for_each_drv(dev->bus, NULL, &data, |
889 | __device_attach_driver); | |
890 | if (!ret && allow_async && data.have_async) { | |
891 | /* | |
892 | * If we could not find appropriate driver | |
893 | * synchronously and we are allowed to do | |
894 | * async probes and there are drivers that | |
895 | * want to probe asynchronously, we'll | |
896 | * try them. | |
897 | */ | |
898 | dev_dbg(dev, "scheduling asynchronous probe\n"); | |
899 | get_device(dev); | |
c37e20ea | 900 | async_schedule_dev(__device_attach_async_helper, dev); |
765230b5 DT |
901 | } else { |
902 | pm_request_idle(dev); | |
903 | } | |
ddef08dd RW |
904 | |
905 | if (dev->parent) | |
906 | pm_runtime_put(dev->parent); | |
21c7f30b | 907 | } |
8497d6a2 | 908 | out_unlock: |
8e9394ce | 909 | device_unlock(dev); |
0d3e5a2e | 910 | return ret; |
2287c322 | 911 | } |
765230b5 DT |
912 | |
913 | /** | |
914 | * device_attach - try to attach device to a driver. | |
915 | * @dev: device. | |
916 | * | |
917 | * Walk the list of drivers that the bus has and call | |
918 | * driver_probe_device() for each pair. If a compatible | |
919 | * pair is found, break out and return. | |
920 | * | |
921 | * Returns 1 if the device was bound to a driver; | |
922 | * 0 if no matching driver was found; | |
923 | * -ENODEV if the device is not registered. | |
924 | * | |
925 | * When called for a USB interface, @dev->parent lock must be held. | |
926 | */ | |
927 | int device_attach(struct device *dev) | |
928 | { | |
929 | return __device_attach(dev, false); | |
930 | } | |
4a3ad20c | 931 | EXPORT_SYMBOL_GPL(device_attach); |
2287c322 | 932 | |
765230b5 DT |
933 | void device_initial_probe(struct device *dev) |
934 | { | |
935 | __device_attach(dev, true); | |
936 | } | |
937 | ||
ed88747c AD |
938 | /* |
939 | * __device_driver_lock - acquire locks needed to manipulate dev->drv | |
940 | * @dev: Device we will update driver info for | |
941 | * @parent: Parent device. Needed if the bus requires parent lock | |
942 | * | |
943 | * This function will take the required locks for manipulating dev->drv. | |
944 | * Normally this will just be the @dev lock, but when called for a USB | |
945 | * interface, @parent lock will be held as well. | |
946 | */ | |
947 | static void __device_driver_lock(struct device *dev, struct device *parent) | |
948 | { | |
949 | if (parent && dev->bus->need_parent_lock) | |
950 | device_lock(parent); | |
951 | device_lock(dev); | |
952 | } | |
953 | ||
954 | /* | |
955 | * __device_driver_unlock - release locks needed to manipulate dev->drv | |
956 | * @dev: Device we will update driver info for | |
957 | * @parent: Parent device. Needed if the bus requires parent lock | |
958 | * | |
959 | * This function will release the required locks for manipulating dev->drv. | |
960 | * Normally this will just be the the @dev lock, but when called for a | |
961 | * USB interface, @parent lock will be released as well. | |
962 | */ | |
963 | static void __device_driver_unlock(struct device *dev, struct device *parent) | |
964 | { | |
965 | device_unlock(dev); | |
966 | if (parent && dev->bus->need_parent_lock) | |
967 | device_unlock(parent); | |
968 | } | |
969 | ||
970 | /** | |
971 | * device_driver_attach - attach a specific driver to a specific device | |
972 | * @drv: Driver to attach | |
973 | * @dev: Device to attach it to | |
974 | * | |
975 | * Manually attach driver to a device. Will acquire both @dev lock and | |
976 | * @dev->parent lock if needed. | |
977 | */ | |
978 | int device_driver_attach(struct device_driver *drv, struct device *dev) | |
979 | { | |
980 | int ret = 0; | |
981 | ||
982 | __device_driver_lock(dev, dev->parent); | |
983 | ||
984 | /* | |
985 | * If device has been removed or someone has already successfully | |
986 | * bound a driver before us just skip the driver probe call. | |
987 | */ | |
988 | if (!dev->p->dead && !dev->driver) | |
989 | ret = driver_probe_device(drv, dev); | |
990 | ||
991 | __device_driver_unlock(dev, dev->parent); | |
992 | ||
993 | return ret; | |
994 | } | |
995 | ||
ef0ff683 AD |
996 | static void __driver_attach_async_helper(void *_dev, async_cookie_t cookie) |
997 | { | |
998 | struct device *dev = _dev; | |
999 | struct device_driver *drv; | |
1000 | int ret = 0; | |
1001 | ||
1002 | __device_driver_lock(dev, dev->parent); | |
1003 | ||
1004 | drv = dev->p->async_driver; | |
1005 | ||
1006 | /* | |
1007 | * If device has been removed or someone has already successfully | |
1008 | * bound a driver before us just skip the driver probe call. | |
1009 | */ | |
1010 | if (!dev->p->dead && !dev->driver) | |
1011 | ret = driver_probe_device(drv, dev); | |
1012 | ||
1013 | __device_driver_unlock(dev, dev->parent); | |
1014 | ||
1015 | dev_dbg(dev, "driver %s async attach completed: %d\n", drv->name, ret); | |
1016 | ||
1017 | put_device(dev); | |
1018 | } | |
1019 | ||
4a3ad20c | 1020 | static int __driver_attach(struct device *dev, void *data) |
2287c322 | 1021 | { |
4a3ad20c | 1022 | struct device_driver *drv = data; |
656b8035 | 1023 | int ret; |
0d3e5a2e PM |
1024 | |
1025 | /* | |
1026 | * Lock device and try to bind to it. We drop the error | |
1027 | * here and always return 0, because we need to keep trying | |
1028 | * to bind to devices and some drivers will return an error | |
1029 | * simply if it didn't support the device. | |
1030 | * | |
1031 | * driver_probe_device() will spit a warning if there | |
1032 | * is an error. | |
1033 | */ | |
1034 | ||
656b8035 TV |
1035 | ret = driver_match_device(drv, dev); |
1036 | if (ret == 0) { | |
1037 | /* no match */ | |
6cd49586 | 1038 | return 0; |
656b8035 TV |
1039 | } else if (ret == -EPROBE_DEFER) { |
1040 | dev_dbg(dev, "Device match requests probe deferral\n"); | |
1041 | driver_deferred_probe_add(dev); | |
1042 | } else if (ret < 0) { | |
eb7fbc9f | 1043 | dev_dbg(dev, "Bus failed to match device: %d\n", ret); |
656b8035 TV |
1044 | return ret; |
1045 | } /* ret > 0 means positive match */ | |
6cd49586 | 1046 | |
ef0ff683 AD |
1047 | if (driver_allows_async_probing(drv)) { |
1048 | /* | |
1049 | * Instead of probing the device synchronously we will | |
1050 | * probe it asynchronously to allow for more parallelism. | |
1051 | * | |
1052 | * We only take the device lock here in order to guarantee | |
1053 | * that the dev->driver and async_driver fields are protected | |
1054 | */ | |
1055 | dev_dbg(dev, "probing driver %s asynchronously\n", drv->name); | |
1056 | device_lock(dev); | |
1057 | if (!dev->driver) { | |
1058 | get_device(dev); | |
1059 | dev->p->async_driver = drv; | |
c37e20ea | 1060 | async_schedule_dev(__driver_attach_async_helper, dev); |
ef0ff683 AD |
1061 | } |
1062 | device_unlock(dev); | |
1063 | return 0; | |
1064 | } | |
1065 | ||
ed88747c | 1066 | device_driver_attach(drv, dev); |
0d3e5a2e | 1067 | |
07e4a3e2 | 1068 | return 0; |
1069 | } | |
1070 | ||
1071 | /** | |
4a3ad20c GKH |
1072 | * driver_attach - try to bind driver to devices. |
1073 | * @drv: driver. | |
07e4a3e2 | 1074 | * |
4a3ad20c GKH |
1075 | * Walk the list of devices that the bus has on it and try to |
1076 | * match the driver with each one. If driver_probe_device() | |
1077 | * returns 0 and the @dev->driver is set, we've found a | |
1078 | * compatible pair. | |
07e4a3e2 | 1079 | */ |
4a3ad20c | 1080 | int driver_attach(struct device_driver *drv) |
07e4a3e2 | 1081 | { |
f86db396 | 1082 | return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach); |
07e4a3e2 | 1083 | } |
4a3ad20c | 1084 | EXPORT_SYMBOL_GPL(driver_attach); |
07e4a3e2 | 1085 | |
ab71c6f0 | 1086 | /* |
8e9394ce GKH |
1087 | * __device_release_driver() must be called with @dev lock held. |
1088 | * When called for a USB interface, @dev->parent lock must be held as well. | |
07e4a3e2 | 1089 | */ |
9ed98953 | 1090 | static void __device_release_driver(struct device *dev, struct device *parent) |
07e4a3e2 | 1091 | { |
4a3ad20c | 1092 | struct device_driver *drv; |
07e4a3e2 | 1093 | |
ef2c5174 | 1094 | drv = dev->driver; |
c95a6b05 | 1095 | if (drv) { |
9ed98953 | 1096 | while (device_links_busy(dev)) { |
ed88747c | 1097 | __device_driver_unlock(dev, parent); |
9ed98953 RW |
1098 | |
1099 | device_links_unbind_consumers(dev); | |
9ed98953 | 1100 | |
ed88747c | 1101 | __device_driver_lock(dev, parent); |
9ed98953 RW |
1102 | /* |
1103 | * A concurrent invocation of the same function might | |
1104 | * have released the driver successfully while this one | |
1105 | * was waiting, so check for that. | |
1106 | */ | |
1107 | if (dev->driver != drv) | |
1108 | return; | |
1109 | } | |
1110 | ||
e1866b33 | 1111 | pm_runtime_get_sync(dev); |
21d5c57b | 1112 | pm_runtime_clean_up_links(dev); |
5e928f77 | 1113 | |
1901fb26 | 1114 | driver_sysfs_remove(dev); |
0d3e5a2e | 1115 | |
116af378 | 1116 | if (dev->bus) |
c6f7e72a | 1117 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
116af378 BH |
1118 | BUS_NOTIFY_UNBIND_DRIVER, |
1119 | dev); | |
1120 | ||
baab52de | 1121 | pm_runtime_put_sync(dev); |
e1866b33 | 1122 | |
8fd456ec | 1123 | device_remove_file(dev, &dev_attr_state_synced); |
23b69044 DT |
1124 | device_remove_groups(dev, drv->dev_groups); |
1125 | ||
0f836ca4 | 1126 | if (dev->bus && dev->bus->remove) |
594c8281 RK |
1127 | dev->bus->remove(dev); |
1128 | else if (drv->remove) | |
0d3e5a2e | 1129 | drv->remove(dev); |
9ed98953 RW |
1130 | |
1131 | device_links_driver_cleanup(dev); | |
09515ef5 | 1132 | |
9ac7849e | 1133 | devres_release_all(dev); |
376991db | 1134 | arch_teardown_dma_ops(dev); |
0d3e5a2e | 1135 | dev->driver = NULL; |
0998d063 | 1136 | dev_set_drvdata(dev, NULL); |
e90d5532 RW |
1137 | if (dev->pm_domain && dev->pm_domain->dismiss) |
1138 | dev->pm_domain->dismiss(dev); | |
5de85b9d | 1139 | pm_runtime_reinit(dev); |
08810a41 | 1140 | dev_pm_set_driver_flags(dev, 0); |
e90d5532 | 1141 | |
8940b4f3 | 1142 | klist_remove(&dev->p->knode_driver); |
aa8e54b5 | 1143 | device_pm_check_callbacks(dev); |
309b7d60 JR |
1144 | if (dev->bus) |
1145 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
1146 | BUS_NOTIFY_UNBOUND_DRIVER, | |
1147 | dev); | |
1455cf8d DT |
1148 | |
1149 | kobject_uevent(&dev->kobj, KOBJ_UNBIND); | |
0d3e5a2e | 1150 | } |
07e4a3e2 | 1151 | } |
1152 | ||
9ed98953 RW |
1153 | void device_release_driver_internal(struct device *dev, |
1154 | struct device_driver *drv, | |
1155 | struct device *parent) | |
4bdb3550 | 1156 | { |
ed88747c | 1157 | __device_driver_lock(dev, parent); |
4bdb3550 | 1158 | |
4bdb3550 | 1159 | if (!drv || drv == dev->driver) |
9ed98953 | 1160 | __device_release_driver(dev, parent); |
4bdb3550 | 1161 | |
ed88747c | 1162 | __device_driver_unlock(dev, parent); |
4bdb3550 RW |
1163 | } |
1164 | ||
ab71c6f0 | 1165 | /** |
4a3ad20c GKH |
1166 | * device_release_driver - manually detach device from driver. |
1167 | * @dev: device. | |
ab71c6f0 | 1168 | * |
4a3ad20c | 1169 | * Manually detach device from driver. |
8e9394ce | 1170 | * When called for a USB interface, @dev->parent lock must be held. |
9ed98953 RW |
1171 | * |
1172 | * If this function is to be called with @dev->parent lock held, ensure that | |
1173 | * the device's consumers are unbound in advance or that their locks can be | |
1174 | * acquired under the @dev->parent lock. | |
ab71c6f0 | 1175 | */ |
4a3ad20c | 1176 | void device_release_driver(struct device *dev) |
94e7b1c5 | 1177 | { |
c95a6b05 AS |
1178 | /* |
1179 | * If anyone calls device_release_driver() recursively from | |
1180 | * within their ->remove callback for the same device, they | |
1181 | * will deadlock right here. | |
1182 | */ | |
4bdb3550 | 1183 | device_release_driver_internal(dev, NULL, NULL); |
94e7b1c5 | 1184 | } |
4a3ad20c | 1185 | EXPORT_SYMBOL_GPL(device_release_driver); |
c95a6b05 | 1186 | |
ed88747c AD |
1187 | /** |
1188 | * device_driver_detach - detach driver from a specific device | |
1189 | * @dev: device to detach driver from | |
1190 | * | |
1191 | * Detach driver from device. Will acquire both @dev lock and @dev->parent | |
1192 | * lock if needed. | |
1193 | */ | |
1194 | void device_driver_detach(struct device *dev) | |
1195 | { | |
1196 | device_release_driver_internal(dev, NULL, dev->parent); | |
1197 | } | |
1198 | ||
07e4a3e2 | 1199 | /** |
1200 | * driver_detach - detach driver from all devices it controls. | |
1201 | * @drv: driver. | |
1202 | */ | |
4a3ad20c | 1203 | void driver_detach(struct device_driver *drv) |
07e4a3e2 | 1204 | { |
8940b4f3 | 1205 | struct device_private *dev_prv; |
4a3ad20c | 1206 | struct device *dev; |
c95a6b05 | 1207 | |
c37d721c AD |
1208 | if (driver_allows_async_probing(drv)) |
1209 | async_synchronize_full(); | |
1210 | ||
c95a6b05 | 1211 | for (;;) { |
e5dd1278 GKH |
1212 | spin_lock(&drv->p->klist_devices.k_lock); |
1213 | if (list_empty(&drv->p->klist_devices.k_list)) { | |
1214 | spin_unlock(&drv->p->klist_devices.k_lock); | |
c95a6b05 AS |
1215 | break; |
1216 | } | |
a3a87d66 | 1217 | dev_prv = list_last_entry(&drv->p->klist_devices.k_list, |
8940b4f3 GKH |
1218 | struct device_private, |
1219 | knode_driver.n_node); | |
1220 | dev = dev_prv->device; | |
c95a6b05 | 1221 | get_device(dev); |
e5dd1278 | 1222 | spin_unlock(&drv->p->klist_devices.k_lock); |
4bdb3550 | 1223 | device_release_driver_internal(dev, drv, dev->parent); |
c95a6b05 AS |
1224 | put_device(dev); |
1225 | } | |
07e4a3e2 | 1226 | } |