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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 | ||
e2cec7d6 JS |
227 | #ifdef CONFIG_MODULES |
228 | /* | |
229 | * In the case of modules, set the default probe timeout to | |
230 | * 30 seconds to give userland some time to load needed modules | |
231 | */ | |
64c775fb | 232 | int driver_deferred_probe_timeout = 30; |
e2cec7d6 JS |
233 | #else |
234 | /* In the case of !modules, no probe timeout needed */ | |
64c775fb | 235 | int driver_deferred_probe_timeout = -1; |
e2cec7d6 | 236 | #endif |
64c775fb JS |
237 | EXPORT_SYMBOL_GPL(driver_deferred_probe_timeout); |
238 | ||
25b4e70d RH |
239 | static int __init deferred_probe_timeout_setup(char *str) |
240 | { | |
63c98047 MS |
241 | int timeout; |
242 | ||
243 | if (!kstrtoint(str, 10, &timeout)) | |
64c775fb | 244 | driver_deferred_probe_timeout = timeout; |
25b4e70d RH |
245 | return 1; |
246 | } | |
247 | __setup("deferred_probe_timeout=", deferred_probe_timeout_setup); | |
248 | ||
249 | /** | |
250 | * driver_deferred_probe_check_state() - Check deferred probe state | |
251 | * @dev: device to check | |
252 | * | |
c8c43cee JS |
253 | * Return: |
254 | * -ENODEV if initcalls have completed and modules are disabled. | |
255 | * -ETIMEDOUT if the deferred probe timeout was set and has expired | |
256 | * and modules are enabled. | |
257 | * -EPROBE_DEFER in other cases. | |
25b4e70d RH |
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 | { | |
0e9f8d09 JS |
264 | if (!IS_ENABLED(CONFIG_MODULES) && initcalls_done) { |
265 | dev_warn(dev, "ignoring dependency for device, assuming no driver"); | |
266 | return -ENODEV; | |
267 | } | |
62a6bc3a | 268 | |
64c775fb | 269 | if (!driver_deferred_probe_timeout) { |
0e9f8d09 JS |
270 | dev_WARN(dev, "deferred probe timeout, ignoring dependency"); |
271 | return -ETIMEDOUT; | |
272 | } | |
62a6bc3a | 273 | |
25b4e70d RH |
274 | return -EPROBE_DEFER; |
275 | } | |
276 | ||
277 | static void deferred_probe_timeout_work_func(struct work_struct *work) | |
278 | { | |
279 | struct device_private *private, *p; | |
280 | ||
64c775fb | 281 | driver_deferred_probe_timeout = 0; |
25b4e70d RH |
282 | driver_deferred_probe_trigger(); |
283 | flush_work(&deferred_probe_work); | |
284 | ||
285 | list_for_each_entry_safe(private, p, &deferred_probe_pending_list, deferred_probe) | |
286 | dev_info(private->device, "deferred probe pending"); | |
287 | } | |
288 | static DECLARE_DELAYED_WORK(deferred_probe_timeout_work, deferred_probe_timeout_work_func); | |
289 | ||
d1c3414c GL |
290 | /** |
291 | * deferred_probe_initcall() - Enable probing of deferred devices | |
292 | * | |
293 | * We don't want to get in the way when the bulk of drivers are getting probed. | |
294 | * Instead, this initcall makes sure that deferred probing is delayed until | |
295 | * late_initcall time. | |
296 | */ | |
297 | static int deferred_probe_initcall(void) | |
298 | { | |
28af109a JMC |
299 | deferred_devices = debugfs_create_file("devices_deferred", 0444, NULL, |
300 | NULL, &deferred_devs_fops); | |
301 | ||
d1c3414c GL |
302 | driver_deferred_probe_enable = true; |
303 | driver_deferred_probe_trigger(); | |
d72cca1e | 304 | /* Sort as many dependencies as possible before exiting initcalls */ |
2c507e46 | 305 | flush_work(&deferred_probe_work); |
25b4e70d RH |
306 | initcalls_done = true; |
307 | ||
308 | /* | |
309 | * Trigger deferred probe again, this time we won't defer anything | |
310 | * that is optional | |
311 | */ | |
312 | driver_deferred_probe_trigger(); | |
313 | flush_work(&deferred_probe_work); | |
314 | ||
64c775fb | 315 | if (driver_deferred_probe_timeout > 0) { |
25b4e70d | 316 | schedule_delayed_work(&deferred_probe_timeout_work, |
64c775fb | 317 | driver_deferred_probe_timeout * HZ); |
25b4e70d | 318 | } |
d1c3414c GL |
319 | return 0; |
320 | } | |
321 | late_initcall(deferred_probe_initcall); | |
07e4a3e2 | 322 | |
28af109a JMC |
323 | static void __exit deferred_probe_exit(void) |
324 | { | |
325 | debugfs_remove_recursive(deferred_devices); | |
326 | } | |
327 | __exitcall(deferred_probe_exit); | |
328 | ||
6b9cb427 TV |
329 | /** |
330 | * device_is_bound() - Check if device is bound to a driver | |
331 | * @dev: device to check | |
332 | * | |
333 | * Returns true if passed device has already finished probing successfully | |
334 | * against a driver. | |
335 | * | |
336 | * This function must be called with the device lock held. | |
337 | */ | |
338 | bool device_is_bound(struct device *dev) | |
339 | { | |
3ded9104 | 340 | return dev->p && klist_node_attached(&dev->p->knode_driver); |
6b9cb427 TV |
341 | } |
342 | ||
1901fb26 | 343 | static void driver_bound(struct device *dev) |
07e4a3e2 | 344 | { |
6b9cb427 | 345 | if (device_is_bound(dev)) { |
f86db396 | 346 | printk(KERN_WARNING "%s: device %s already bound\n", |
2b3a302a | 347 | __func__, kobject_name(&dev->kobj)); |
1901fb26 | 348 | return; |
f86db396 | 349 | } |
4c898c7f | 350 | |
94f8cc0e FR |
351 | pr_debug("driver: '%s': %s: bound to device '%s'\n", dev->driver->name, |
352 | __func__, dev_name(dev)); | |
116af378 | 353 | |
fbb88fad | 354 | klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices); |
9ed98953 | 355 | device_links_driver_bound(dev); |
fbb88fad | 356 | |
aa8e54b5 TV |
357 | device_pm_check_callbacks(dev); |
358 | ||
8b0372a2 GKH |
359 | /* |
360 | * Make sure the device is no longer in one of the deferred lists and | |
361 | * kick off retrying all pending devices | |
362 | */ | |
d1c3414c GL |
363 | driver_deferred_probe_del(dev); |
364 | driver_deferred_probe_trigger(); | |
365 | ||
116af378 | 366 | if (dev->bus) |
c6f7e72a | 367 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
116af378 | 368 | BUS_NOTIFY_BOUND_DRIVER, dev); |
1455cf8d DT |
369 | |
370 | kobject_uevent(&dev->kobj, KOBJ_BIND); | |
1901fb26 KS |
371 | } |
372 | ||
3c47d19f AS |
373 | static ssize_t coredump_store(struct device *dev, struct device_attribute *attr, |
374 | const char *buf, size_t count) | |
375 | { | |
376 | device_lock(dev); | |
1fe56e0c | 377 | dev->driver->coredump(dev); |
3c47d19f AS |
378 | device_unlock(dev); |
379 | ||
380 | return count; | |
381 | } | |
382 | static DEVICE_ATTR_WO(coredump); | |
383 | ||
1901fb26 KS |
384 | static int driver_sysfs_add(struct device *dev) |
385 | { | |
386 | int ret; | |
387 | ||
45daef0f MD |
388 | if (dev->bus) |
389 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
390 | BUS_NOTIFY_BIND_DRIVER, dev); | |
391 | ||
e5dd1278 | 392 | ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj, |
3c47d19f AS |
393 | kobject_name(&dev->kobj)); |
394 | if (ret) | |
395 | goto fail; | |
396 | ||
397 | ret = sysfs_create_link(&dev->kobj, &dev->driver->p->kobj, | |
398 | "driver"); | |
399 | if (ret) | |
400 | goto rm_dev; | |
401 | ||
402 | if (!IS_ENABLED(CONFIG_DEV_COREDUMP) || !dev->driver->coredump || | |
403 | !device_create_file(dev, &dev_attr_coredump)) | |
404 | return 0; | |
405 | ||
406 | sysfs_remove_link(&dev->kobj, "driver"); | |
407 | ||
408 | rm_dev: | |
409 | sysfs_remove_link(&dev->driver->p->kobj, | |
07e4a3e2 | 410 | kobject_name(&dev->kobj)); |
3c47d19f AS |
411 | |
412 | fail: | |
f86db396 | 413 | return ret; |
07e4a3e2 PM |
414 | } |
415 | ||
1901fb26 KS |
416 | static void driver_sysfs_remove(struct device *dev) |
417 | { | |
418 | struct device_driver *drv = dev->driver; | |
419 | ||
420 | if (drv) { | |
3c47d19f AS |
421 | if (drv->coredump) |
422 | device_remove_file(dev, &dev_attr_coredump); | |
e5dd1278 | 423 | sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj)); |
1901fb26 KS |
424 | sysfs_remove_link(&dev->kobj, "driver"); |
425 | } | |
426 | } | |
427 | ||
428 | /** | |
4a3ad20c GKH |
429 | * device_bind_driver - bind a driver to one device. |
430 | * @dev: device. | |
1901fb26 | 431 | * |
4a3ad20c GKH |
432 | * Allow manual attachment of a driver to a device. |
433 | * Caller must have already set @dev->driver. | |
1901fb26 | 434 | * |
4a3ad20c GKH |
435 | * Note that this does not modify the bus reference count |
436 | * nor take the bus's rwsem. Please verify those are accounted | |
437 | * for before calling this. (It is ok to call with no other effort | |
438 | * from a driver's probe() method.) | |
1901fb26 | 439 | * |
8e9394ce | 440 | * This function must be called with the device lock held. |
1901fb26 KS |
441 | */ |
442 | int device_bind_driver(struct device *dev) | |
443 | { | |
cb986b74 CH |
444 | int ret; |
445 | ||
446 | ret = driver_sysfs_add(dev); | |
447 | if (!ret) | |
448 | driver_bound(dev); | |
14b6257a AS |
449 | else if (dev->bus) |
450 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
451 | BUS_NOTIFY_DRIVER_NOT_BOUND, dev); | |
cb986b74 | 452 | return ret; |
1901fb26 | 453 | } |
4a3ad20c | 454 | EXPORT_SYMBOL_GPL(device_bind_driver); |
1901fb26 | 455 | |
d779249e | 456 | static atomic_t probe_count = ATOMIC_INIT(0); |
735a7ffb AM |
457 | static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue); |
458 | ||
0ff26c66 AH |
459 | static void driver_deferred_probe_add_trigger(struct device *dev, |
460 | int local_trigger_count) | |
461 | { | |
462 | driver_deferred_probe_add(dev); | |
463 | /* Did a trigger occur while probing? Need to re-trigger if yes */ | |
464 | if (local_trigger_count != atomic_read(&deferred_trigger_count)) | |
465 | driver_deferred_probe_trigger(); | |
466 | } | |
467 | ||
21c7f30b | 468 | static int really_probe(struct device *dev, struct device_driver *drv) |
07e4a3e2 | 469 | { |
013c074f | 470 | int ret = -EPROBE_DEFER; |
58b116bc | 471 | int local_trigger_count = atomic_read(&deferred_trigger_count); |
c5f06274 RH |
472 | bool test_remove = IS_ENABLED(CONFIG_DEBUG_TEST_DRIVER_REMOVE) && |
473 | !drv->suppress_bind_attrs; | |
07e4a3e2 | 474 | |
013c074f SG |
475 | if (defer_all_probes) { |
476 | /* | |
477 | * Value of defer_all_probes can be set only by | |
dbf03d65 | 478 | * device_block_probing() which, in turn, will call |
013c074f SG |
479 | * wait_for_device_probe() right after that to avoid any races. |
480 | */ | |
481 | dev_dbg(dev, "Driver %s force probe deferral\n", drv->name); | |
482 | driver_deferred_probe_add(dev); | |
483 | return ret; | |
484 | } | |
485 | ||
9ed98953 | 486 | ret = device_links_check_suppliers(dev); |
0ff26c66 AH |
487 | if (ret == -EPROBE_DEFER) |
488 | driver_deferred_probe_add_trigger(dev, local_trigger_count); | |
9ed98953 RW |
489 | if (ret) |
490 | return ret; | |
491 | ||
d779249e | 492 | atomic_inc(&probe_count); |
7dc72b28 | 493 | pr_debug("bus: '%s': %s: probing driver %s with device %s\n", |
1e0b2cf9 | 494 | drv->bus->name, __func__, drv->name, dev_name(dev)); |
7c35e699 GU |
495 | if (!list_empty(&dev->devres_head)) { |
496 | dev_crit(dev, "Resources present before probing\n"); | |
497 | return -EBUSY; | |
498 | } | |
07e4a3e2 | 499 | |
bea5b158 | 500 | re_probe: |
07e4a3e2 | 501 | dev->driver = drv; |
ab78029e LW |
502 | |
503 | /* If using pinctrl, bind pins now before probing */ | |
504 | ret = pinctrl_bind_pins(dev); | |
505 | if (ret) | |
14b6257a | 506 | goto pinctrl_bind_failed; |
ab78029e | 507 | |
ccf640f4 CH |
508 | if (dev->bus->dma_configure) { |
509 | ret = dev->bus->dma_configure(dev); | |
510 | if (ret) | |
0b777eee | 511 | goto probe_failed; |
ccf640f4 | 512 | } |
09515ef5 | 513 | |
1901fb26 KS |
514 | if (driver_sysfs_add(dev)) { |
515 | printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n", | |
1e0b2cf9 | 516 | __func__, dev_name(dev)); |
1901fb26 KS |
517 | goto probe_failed; |
518 | } | |
519 | ||
e90d5532 RW |
520 | if (dev->pm_domain && dev->pm_domain->activate) { |
521 | ret = dev->pm_domain->activate(dev); | |
522 | if (ret) | |
523 | goto probe_failed; | |
524 | } | |
525 | ||
594c8281 RK |
526 | if (dev->bus->probe) { |
527 | ret = dev->bus->probe(dev); | |
1901fb26 | 528 | if (ret) |
d779249e | 529 | goto probe_failed; |
594c8281 | 530 | } else if (drv->probe) { |
0d3e5a2e | 531 | ret = drv->probe(dev); |
1901fb26 | 532 | if (ret) |
d779249e | 533 | goto probe_failed; |
f86db396 | 534 | } |
1901fb26 | 535 | |
23b69044 DT |
536 | if (device_add_groups(dev, drv->dev_groups)) { |
537 | dev_err(dev, "device_add_groups() failed\n"); | |
538 | goto dev_groups_failed; | |
539 | } | |
540 | ||
bea5b158 RH |
541 | if (test_remove) { |
542 | test_remove = false; | |
543 | ||
23b69044 DT |
544 | device_remove_groups(dev, drv->dev_groups); |
545 | ||
bdacd1b4 | 546 | if (dev->bus->remove) |
bea5b158 RH |
547 | dev->bus->remove(dev); |
548 | else if (drv->remove) | |
549 | drv->remove(dev); | |
550 | ||
551 | devres_release_all(dev); | |
552 | driver_sysfs_remove(dev); | |
553 | dev->driver = NULL; | |
554 | dev_set_drvdata(dev, NULL); | |
555 | if (dev->pm_domain && dev->pm_domain->dismiss) | |
556 | dev->pm_domain->dismiss(dev); | |
557 | pm_runtime_reinit(dev); | |
558 | ||
559 | goto re_probe; | |
560 | } | |
561 | ||
ef0eebc0 DA |
562 | pinctrl_init_done(dev); |
563 | ||
e90d5532 RW |
564 | if (dev->pm_domain && dev->pm_domain->sync) |
565 | dev->pm_domain->sync(dev); | |
566 | ||
1901fb26 | 567 | driver_bound(dev); |
0d3e5a2e | 568 | ret = 1; |
7dc72b28 | 569 | pr_debug("bus: '%s': %s: bound device %s to driver %s\n", |
1e0b2cf9 | 570 | drv->bus->name, __func__, dev_name(dev), drv->name); |
d779249e | 571 | goto done; |
0d3e5a2e | 572 | |
23b69044 DT |
573 | dev_groups_failed: |
574 | if (dev->bus->remove) | |
575 | dev->bus->remove(dev); | |
576 | else if (drv->remove) | |
577 | drv->remove(dev); | |
d779249e | 578 | probe_failed: |
14b6257a AS |
579 | if (dev->bus) |
580 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
581 | BUS_NOTIFY_DRIVER_NOT_BOUND, dev); | |
582 | pinctrl_bind_failed: | |
9ed98953 | 583 | device_links_no_driver(dev); |
9ac7849e | 584 | devres_release_all(dev); |
0b777eee | 585 | arch_teardown_dma_ops(dev); |
1901fb26 KS |
586 | driver_sysfs_remove(dev); |
587 | dev->driver = NULL; | |
0998d063 | 588 | dev_set_drvdata(dev, NULL); |
e90d5532 RW |
589 | if (dev->pm_domain && dev->pm_domain->dismiss) |
590 | dev->pm_domain->dismiss(dev); | |
5de85b9d | 591 | pm_runtime_reinit(dev); |
08810a41 | 592 | dev_pm_set_driver_flags(dev, 0); |
1901fb26 | 593 | |
bb2b4075 SS |
594 | switch (ret) { |
595 | case -EPROBE_DEFER: | |
d1c3414c | 596 | /* Driver requested deferred probing */ |
13fcffbb | 597 | dev_dbg(dev, "Driver %s requests probe deferral\n", drv->name); |
0ff26c66 | 598 | driver_deferred_probe_add_trigger(dev, local_trigger_count); |
bb2b4075 SS |
599 | break; |
600 | case -ENODEV: | |
601 | case -ENXIO: | |
602 | pr_debug("%s: probe of %s rejects match %d\n", | |
603 | drv->name, dev_name(dev), ret); | |
604 | break; | |
605 | default: | |
0d3e5a2e PM |
606 | /* driver matched but the probe failed */ |
607 | printk(KERN_WARNING | |
608 | "%s: probe of %s failed with error %d\n", | |
1e0b2cf9 | 609 | drv->name, dev_name(dev), ret); |
0d3e5a2e | 610 | } |
c578abbc CH |
611 | /* |
612 | * Ignore errors returned by ->probe so that the next driver can try | |
613 | * its luck. | |
614 | */ | |
615 | ret = 0; | |
d779249e | 616 | done: |
d779249e | 617 | atomic_dec(&probe_count); |
735a7ffb | 618 | wake_up(&probe_waitqueue); |
d779249e GKH |
619 | return ret; |
620 | } | |
621 | ||
0a50f61c TP |
622 | /* |
623 | * For initcall_debug, show the driver probe time. | |
624 | */ | |
625 | static int really_probe_debug(struct device *dev, struct device_driver *drv) | |
626 | { | |
627 | ktime_t calltime, delta, rettime; | |
628 | int ret; | |
629 | ||
630 | calltime = ktime_get(); | |
631 | ret = really_probe(dev, drv); | |
632 | rettime = ktime_get(); | |
633 | delta = ktime_sub(rettime, calltime); | |
634 | printk(KERN_DEBUG "probe of %s returned %d after %lld usecs\n", | |
635 | dev_name(dev), ret, (s64) ktime_to_us(delta)); | |
636 | return ret; | |
637 | } | |
638 | ||
d779249e GKH |
639 | /** |
640 | * driver_probe_done | |
641 | * Determine if the probe sequence is finished or not. | |
642 | * | |
643 | * Should somehow figure out how to use a semaphore, not an atomic variable... | |
644 | */ | |
645 | int driver_probe_done(void) | |
646 | { | |
927f8287 AS |
647 | int local_probe_count = atomic_read(&probe_count); |
648 | ||
649 | pr_debug("%s: probe_count = %d\n", __func__, local_probe_count); | |
650 | if (local_probe_count) | |
d779249e GKH |
651 | return -EBUSY; |
652 | return 0; | |
653 | } | |
654 | ||
216773a7 AV |
655 | /** |
656 | * wait_for_device_probe | |
657 | * Wait for device probing to be completed. | |
216773a7 | 658 | */ |
b23530eb | 659 | void wait_for_device_probe(void) |
216773a7 | 660 | { |
013c074f | 661 | /* wait for the deferred probe workqueue to finish */ |
2c507e46 | 662 | flush_work(&deferred_probe_work); |
013c074f | 663 | |
216773a7 | 664 | /* wait for the known devices to complete their probing */ |
b23530eb | 665 | wait_event(probe_waitqueue, atomic_read(&probe_count) == 0); |
216773a7 | 666 | async_synchronize_full(); |
216773a7 | 667 | } |
d4d5291c | 668 | EXPORT_SYMBOL_GPL(wait_for_device_probe); |
216773a7 | 669 | |
d779249e GKH |
670 | /** |
671 | * driver_probe_device - attempt to bind device & driver together | |
672 | * @drv: driver to bind a device to | |
673 | * @dev: device to try to bind to the driver | |
674 | * | |
49b420a1 | 675 | * This function returns -ENODEV if the device is not registered, |
af901ca1 | 676 | * 1 if the device is bound successfully and 0 otherwise. |
d779249e | 677 | * |
8e9394ce GKH |
678 | * This function must be called with @dev lock held. When called for a |
679 | * USB interface, @dev->parent lock must be held as well. | |
ddef08dd RW |
680 | * |
681 | * If the device has a parent, runtime-resume the parent before driver probing. | |
d779249e | 682 | */ |
4a3ad20c | 683 | int driver_probe_device(struct device_driver *drv, struct device *dev) |
d779249e | 684 | { |
d779249e GKH |
685 | int ret = 0; |
686 | ||
f2eaae19 AS |
687 | if (!device_is_registered(dev)) |
688 | return -ENODEV; | |
d779249e | 689 | |
7dc72b28 | 690 | pr_debug("bus: '%s': %s: matched device %s with driver %s\n", |
1e0b2cf9 | 691 | drv->bus->name, __func__, dev_name(dev), drv->name); |
d779249e | 692 | |
b06c0b2f | 693 | pm_runtime_get_suppliers(dev); |
ddef08dd RW |
694 | if (dev->parent) |
695 | pm_runtime_get_sync(dev->parent); | |
696 | ||
5e928f77 | 697 | pm_runtime_barrier(dev); |
0a50f61c TP |
698 | if (initcall_debug) |
699 | ret = really_probe_debug(dev, drv); | |
700 | else | |
701 | ret = really_probe(dev, drv); | |
fa180eb4 | 702 | pm_request_idle(dev); |
d779249e | 703 | |
ddef08dd RW |
704 | if (dev->parent) |
705 | pm_runtime_put(dev->parent); | |
706 | ||
b06c0b2f | 707 | pm_runtime_put_suppliers(dev); |
0d3e5a2e | 708 | return ret; |
07e4a3e2 PM |
709 | } |
710 | ||
1ea61b68 FT |
711 | static inline bool cmdline_requested_async_probing(const char *drv_name) |
712 | { | |
713 | return parse_option_str(async_probe_drv_names, drv_name); | |
714 | } | |
715 | ||
716 | /* The option format is "driver_async_probe=drv_name1,drv_name2,..." */ | |
717 | static int __init save_async_options(char *buf) | |
718 | { | |
719 | if (strlen(buf) >= ASYNC_DRV_NAMES_MAX_LEN) | |
720 | printk(KERN_WARNING | |
721 | "Too long list of driver names for 'driver_async_probe'!\n"); | |
722 | ||
723 | strlcpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN); | |
724 | return 0; | |
725 | } | |
726 | __setup("driver_async_probe=", save_async_options); | |
727 | ||
765230b5 | 728 | bool driver_allows_async_probing(struct device_driver *drv) |
2287c322 | 729 | { |
d173a137 LR |
730 | switch (drv->probe_type) { |
731 | case PROBE_PREFER_ASYNCHRONOUS: | |
f2411da7 LR |
732 | return true; |
733 | ||
d173a137 LR |
734 | case PROBE_FORCE_SYNCHRONOUS: |
735 | return false; | |
736 | ||
737 | default: | |
1ea61b68 FT |
738 | if (cmdline_requested_async_probing(drv->name)) |
739 | return true; | |
740 | ||
80c6e146 | 741 | if (module_requested_async_probing(drv->owner)) |
d173a137 | 742 | return true; |
f2411da7 | 743 | |
d173a137 LR |
744 | return false; |
745 | } | |
765230b5 DT |
746 | } |
747 | ||
748 | struct device_attach_data { | |
749 | struct device *dev; | |
750 | ||
751 | /* | |
752 | * Indicates whether we are are considering asynchronous probing or | |
753 | * not. Only initial binding after device or driver registration | |
754 | * (including deferral processing) may be done asynchronously, the | |
755 | * rest is always synchronous, as we expect it is being done by | |
756 | * request from userspace. | |
757 | */ | |
758 | bool check_async; | |
759 | ||
760 | /* | |
761 | * Indicates if we are binding synchronous or asynchronous drivers. | |
762 | * When asynchronous probing is enabled we'll execute 2 passes | |
763 | * over drivers: first pass doing synchronous probing and second | |
764 | * doing asynchronous probing (if synchronous did not succeed - | |
765 | * most likely because there was no driver requiring synchronous | |
766 | * probing - and we found asynchronous driver during first pass). | |
767 | * The 2 passes are done because we can't shoot asynchronous | |
768 | * probe for given device and driver from bus_for_each_drv() since | |
769 | * driver pointer is not guaranteed to stay valid once | |
770 | * bus_for_each_drv() iterates to the next driver on the bus. | |
771 | */ | |
772 | bool want_async; | |
773 | ||
774 | /* | |
775 | * We'll set have_async to 'true' if, while scanning for matching | |
776 | * driver, we'll encounter one that requests asynchronous probing. | |
777 | */ | |
778 | bool have_async; | |
779 | }; | |
780 | ||
781 | static int __device_attach_driver(struct device_driver *drv, void *_data) | |
782 | { | |
783 | struct device_attach_data *data = _data; | |
784 | struct device *dev = data->dev; | |
785 | bool async_allowed; | |
656b8035 | 786 | int ret; |
765230b5 | 787 | |
656b8035 TV |
788 | ret = driver_match_device(drv, dev); |
789 | if (ret == 0) { | |
790 | /* no match */ | |
49b420a1 | 791 | return 0; |
656b8035 TV |
792 | } else if (ret == -EPROBE_DEFER) { |
793 | dev_dbg(dev, "Device match requests probe deferral\n"); | |
794 | driver_deferred_probe_add(dev); | |
795 | } else if (ret < 0) { | |
796 | dev_dbg(dev, "Bus failed to match device: %d", ret); | |
797 | return ret; | |
798 | } /* ret > 0 means positive match */ | |
49b420a1 | 799 | |
765230b5 DT |
800 | async_allowed = driver_allows_async_probing(drv); |
801 | ||
802 | if (async_allowed) | |
803 | data->have_async = true; | |
804 | ||
805 | if (data->check_async && async_allowed != data->want_async) | |
806 | return 0; | |
807 | ||
0d3e5a2e | 808 | return driver_probe_device(drv, dev); |
2287c322 PM |
809 | } |
810 | ||
765230b5 DT |
811 | static void __device_attach_async_helper(void *_dev, async_cookie_t cookie) |
812 | { | |
813 | struct device *dev = _dev; | |
814 | struct device_attach_data data = { | |
815 | .dev = dev, | |
816 | .check_async = true, | |
817 | .want_async = true, | |
818 | }; | |
819 | ||
820 | device_lock(dev); | |
821 | ||
3451a495 AD |
822 | /* |
823 | * Check if device has already been removed or claimed. This may | |
824 | * happen with driver loading, device discovery/registration, | |
825 | * and deferred probe processing happens all at once with | |
826 | * multiple threads. | |
827 | */ | |
828 | if (dev->p->dead || dev->driver) | |
829 | goto out_unlock; | |
830 | ||
ddef08dd RW |
831 | if (dev->parent) |
832 | pm_runtime_get_sync(dev->parent); | |
833 | ||
765230b5 DT |
834 | bus_for_each_drv(dev->bus, NULL, &data, __device_attach_driver); |
835 | dev_dbg(dev, "async probe completed\n"); | |
836 | ||
837 | pm_request_idle(dev); | |
838 | ||
ddef08dd RW |
839 | if (dev->parent) |
840 | pm_runtime_put(dev->parent); | |
3451a495 | 841 | out_unlock: |
765230b5 DT |
842 | device_unlock(dev); |
843 | ||
844 | put_device(dev); | |
845 | } | |
846 | ||
802a87fd | 847 | static int __device_attach(struct device *dev, bool allow_async) |
07e4a3e2 | 848 | { |
0d3e5a2e PM |
849 | int ret = 0; |
850 | ||
8e9394ce | 851 | device_lock(dev); |
07e4a3e2 | 852 | if (dev->driver) { |
6b9cb427 | 853 | if (device_is_bound(dev)) { |
8497d6a2 SO |
854 | ret = 1; |
855 | goto out_unlock; | |
856 | } | |
f86db396 AM |
857 | ret = device_bind_driver(dev); |
858 | if (ret == 0) | |
859 | ret = 1; | |
c6a46696 CH |
860 | else { |
861 | dev->driver = NULL; | |
862 | ret = 0; | |
863 | } | |
21c7f30b | 864 | } else { |
765230b5 DT |
865 | struct device_attach_data data = { |
866 | .dev = dev, | |
867 | .check_async = allow_async, | |
868 | .want_async = false, | |
869 | }; | |
870 | ||
ddef08dd RW |
871 | if (dev->parent) |
872 | pm_runtime_get_sync(dev->parent); | |
873 | ||
765230b5 DT |
874 | ret = bus_for_each_drv(dev->bus, NULL, &data, |
875 | __device_attach_driver); | |
876 | if (!ret && allow_async && data.have_async) { | |
877 | /* | |
878 | * If we could not find appropriate driver | |
879 | * synchronously and we are allowed to do | |
880 | * async probes and there are drivers that | |
881 | * want to probe asynchronously, we'll | |
882 | * try them. | |
883 | */ | |
884 | dev_dbg(dev, "scheduling asynchronous probe\n"); | |
885 | get_device(dev); | |
c37e20ea | 886 | async_schedule_dev(__device_attach_async_helper, dev); |
765230b5 DT |
887 | } else { |
888 | pm_request_idle(dev); | |
889 | } | |
ddef08dd RW |
890 | |
891 | if (dev->parent) | |
892 | pm_runtime_put(dev->parent); | |
21c7f30b | 893 | } |
8497d6a2 | 894 | out_unlock: |
8e9394ce | 895 | device_unlock(dev); |
0d3e5a2e | 896 | return ret; |
2287c322 | 897 | } |
765230b5 DT |
898 | |
899 | /** | |
900 | * device_attach - try to attach device to a driver. | |
901 | * @dev: device. | |
902 | * | |
903 | * Walk the list of drivers that the bus has and call | |
904 | * driver_probe_device() for each pair. If a compatible | |
905 | * pair is found, break out and return. | |
906 | * | |
907 | * Returns 1 if the device was bound to a driver; | |
908 | * 0 if no matching driver was found; | |
909 | * -ENODEV if the device is not registered. | |
910 | * | |
911 | * When called for a USB interface, @dev->parent lock must be held. | |
912 | */ | |
913 | int device_attach(struct device *dev) | |
914 | { | |
915 | return __device_attach(dev, false); | |
916 | } | |
4a3ad20c | 917 | EXPORT_SYMBOL_GPL(device_attach); |
2287c322 | 918 | |
765230b5 DT |
919 | void device_initial_probe(struct device *dev) |
920 | { | |
921 | __device_attach(dev, true); | |
922 | } | |
923 | ||
ed88747c AD |
924 | /* |
925 | * __device_driver_lock - acquire locks needed to manipulate dev->drv | |
926 | * @dev: Device we will update driver info for | |
927 | * @parent: Parent device. Needed if the bus requires parent lock | |
928 | * | |
929 | * This function will take the required locks for manipulating dev->drv. | |
930 | * Normally this will just be the @dev lock, but when called for a USB | |
931 | * interface, @parent lock will be held as well. | |
932 | */ | |
933 | static void __device_driver_lock(struct device *dev, struct device *parent) | |
934 | { | |
935 | if (parent && dev->bus->need_parent_lock) | |
936 | device_lock(parent); | |
937 | device_lock(dev); | |
938 | } | |
939 | ||
940 | /* | |
941 | * __device_driver_unlock - release locks needed to manipulate dev->drv | |
942 | * @dev: Device we will update driver info for | |
943 | * @parent: Parent device. Needed if the bus requires parent lock | |
944 | * | |
945 | * This function will release the required locks for manipulating dev->drv. | |
946 | * Normally this will just be the the @dev lock, but when called for a | |
947 | * USB interface, @parent lock will be released as well. | |
948 | */ | |
949 | static void __device_driver_unlock(struct device *dev, struct device *parent) | |
950 | { | |
951 | device_unlock(dev); | |
952 | if (parent && dev->bus->need_parent_lock) | |
953 | device_unlock(parent); | |
954 | } | |
955 | ||
956 | /** | |
957 | * device_driver_attach - attach a specific driver to a specific device | |
958 | * @drv: Driver to attach | |
959 | * @dev: Device to attach it to | |
960 | * | |
961 | * Manually attach driver to a device. Will acquire both @dev lock and | |
962 | * @dev->parent lock if needed. | |
963 | */ | |
964 | int device_driver_attach(struct device_driver *drv, struct device *dev) | |
965 | { | |
966 | int ret = 0; | |
967 | ||
968 | __device_driver_lock(dev, dev->parent); | |
969 | ||
970 | /* | |
971 | * If device has been removed or someone has already successfully | |
972 | * bound a driver before us just skip the driver probe call. | |
973 | */ | |
974 | if (!dev->p->dead && !dev->driver) | |
975 | ret = driver_probe_device(drv, dev); | |
976 | ||
977 | __device_driver_unlock(dev, dev->parent); | |
978 | ||
979 | return ret; | |
980 | } | |
981 | ||
ef0ff683 AD |
982 | static void __driver_attach_async_helper(void *_dev, async_cookie_t cookie) |
983 | { | |
984 | struct device *dev = _dev; | |
985 | struct device_driver *drv; | |
986 | int ret = 0; | |
987 | ||
988 | __device_driver_lock(dev, dev->parent); | |
989 | ||
990 | drv = dev->p->async_driver; | |
991 | ||
992 | /* | |
993 | * If device has been removed or someone has already successfully | |
994 | * bound a driver before us just skip the driver probe call. | |
995 | */ | |
996 | if (!dev->p->dead && !dev->driver) | |
997 | ret = driver_probe_device(drv, dev); | |
998 | ||
999 | __device_driver_unlock(dev, dev->parent); | |
1000 | ||
1001 | dev_dbg(dev, "driver %s async attach completed: %d\n", drv->name, ret); | |
1002 | ||
1003 | put_device(dev); | |
1004 | } | |
1005 | ||
4a3ad20c | 1006 | static int __driver_attach(struct device *dev, void *data) |
2287c322 | 1007 | { |
4a3ad20c | 1008 | struct device_driver *drv = data; |
656b8035 | 1009 | int ret; |
0d3e5a2e PM |
1010 | |
1011 | /* | |
1012 | * Lock device and try to bind to it. We drop the error | |
1013 | * here and always return 0, because we need to keep trying | |
1014 | * to bind to devices and some drivers will return an error | |
1015 | * simply if it didn't support the device. | |
1016 | * | |
1017 | * driver_probe_device() will spit a warning if there | |
1018 | * is an error. | |
1019 | */ | |
1020 | ||
656b8035 TV |
1021 | ret = driver_match_device(drv, dev); |
1022 | if (ret == 0) { | |
1023 | /* no match */ | |
6cd49586 | 1024 | return 0; |
656b8035 TV |
1025 | } else if (ret == -EPROBE_DEFER) { |
1026 | dev_dbg(dev, "Device match requests probe deferral\n"); | |
1027 | driver_deferred_probe_add(dev); | |
1028 | } else if (ret < 0) { | |
1029 | dev_dbg(dev, "Bus failed to match device: %d", ret); | |
1030 | return ret; | |
1031 | } /* ret > 0 means positive match */ | |
6cd49586 | 1032 | |
ef0ff683 AD |
1033 | if (driver_allows_async_probing(drv)) { |
1034 | /* | |
1035 | * Instead of probing the device synchronously we will | |
1036 | * probe it asynchronously to allow for more parallelism. | |
1037 | * | |
1038 | * We only take the device lock here in order to guarantee | |
1039 | * that the dev->driver and async_driver fields are protected | |
1040 | */ | |
1041 | dev_dbg(dev, "probing driver %s asynchronously\n", drv->name); | |
1042 | device_lock(dev); | |
1043 | if (!dev->driver) { | |
1044 | get_device(dev); | |
1045 | dev->p->async_driver = drv; | |
c37e20ea | 1046 | async_schedule_dev(__driver_attach_async_helper, dev); |
ef0ff683 AD |
1047 | } |
1048 | device_unlock(dev); | |
1049 | return 0; | |
1050 | } | |
1051 | ||
ed88747c | 1052 | device_driver_attach(drv, dev); |
0d3e5a2e | 1053 | |
07e4a3e2 PM |
1054 | return 0; |
1055 | } | |
1056 | ||
1057 | /** | |
4a3ad20c GKH |
1058 | * driver_attach - try to bind driver to devices. |
1059 | * @drv: driver. | |
07e4a3e2 | 1060 | * |
4a3ad20c GKH |
1061 | * Walk the list of devices that the bus has on it and try to |
1062 | * match the driver with each one. If driver_probe_device() | |
1063 | * returns 0 and the @dev->driver is set, we've found a | |
1064 | * compatible pair. | |
07e4a3e2 | 1065 | */ |
4a3ad20c | 1066 | int driver_attach(struct device_driver *drv) |
07e4a3e2 | 1067 | { |
f86db396 | 1068 | return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach); |
07e4a3e2 | 1069 | } |
4a3ad20c | 1070 | EXPORT_SYMBOL_GPL(driver_attach); |
07e4a3e2 | 1071 | |
ab71c6f0 | 1072 | /* |
8e9394ce GKH |
1073 | * __device_release_driver() must be called with @dev lock held. |
1074 | * When called for a USB interface, @dev->parent lock must be held as well. | |
07e4a3e2 | 1075 | */ |
9ed98953 | 1076 | static void __device_release_driver(struct device *dev, struct device *parent) |
07e4a3e2 | 1077 | { |
4a3ad20c | 1078 | struct device_driver *drv; |
07e4a3e2 | 1079 | |
ef2c5174 | 1080 | drv = dev->driver; |
c95a6b05 | 1081 | if (drv) { |
9ed98953 | 1082 | while (device_links_busy(dev)) { |
ed88747c | 1083 | __device_driver_unlock(dev, parent); |
9ed98953 RW |
1084 | |
1085 | device_links_unbind_consumers(dev); | |
9ed98953 | 1086 | |
ed88747c | 1087 | __device_driver_lock(dev, parent); |
9ed98953 RW |
1088 | /* |
1089 | * A concurrent invocation of the same function might | |
1090 | * have released the driver successfully while this one | |
1091 | * was waiting, so check for that. | |
1092 | */ | |
1093 | if (dev->driver != drv) | |
1094 | return; | |
1095 | } | |
1096 | ||
e1866b33 | 1097 | pm_runtime_get_sync(dev); |
21d5c57b | 1098 | pm_runtime_clean_up_links(dev); |
5e928f77 | 1099 | |
1901fb26 | 1100 | driver_sysfs_remove(dev); |
0d3e5a2e | 1101 | |
116af378 | 1102 | if (dev->bus) |
c6f7e72a | 1103 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
116af378 BH |
1104 | BUS_NOTIFY_UNBIND_DRIVER, |
1105 | dev); | |
1106 | ||
baab52de | 1107 | pm_runtime_put_sync(dev); |
e1866b33 | 1108 | |
23b69044 DT |
1109 | device_remove_groups(dev, drv->dev_groups); |
1110 | ||
0f836ca4 | 1111 | if (dev->bus && dev->bus->remove) |
594c8281 RK |
1112 | dev->bus->remove(dev); |
1113 | else if (drv->remove) | |
0d3e5a2e | 1114 | drv->remove(dev); |
9ed98953 RW |
1115 | |
1116 | device_links_driver_cleanup(dev); | |
09515ef5 | 1117 | |
9ac7849e | 1118 | devres_release_all(dev); |
376991db | 1119 | arch_teardown_dma_ops(dev); |
0d3e5a2e | 1120 | dev->driver = NULL; |
0998d063 | 1121 | dev_set_drvdata(dev, NULL); |
e90d5532 RW |
1122 | if (dev->pm_domain && dev->pm_domain->dismiss) |
1123 | dev->pm_domain->dismiss(dev); | |
5de85b9d | 1124 | pm_runtime_reinit(dev); |
08810a41 | 1125 | dev_pm_set_driver_flags(dev, 0); |
e90d5532 | 1126 | |
8940b4f3 | 1127 | klist_remove(&dev->p->knode_driver); |
aa8e54b5 | 1128 | device_pm_check_callbacks(dev); |
309b7d60 JR |
1129 | if (dev->bus) |
1130 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
1131 | BUS_NOTIFY_UNBOUND_DRIVER, | |
1132 | dev); | |
1455cf8d DT |
1133 | |
1134 | kobject_uevent(&dev->kobj, KOBJ_UNBIND); | |
0d3e5a2e | 1135 | } |
07e4a3e2 PM |
1136 | } |
1137 | ||
9ed98953 RW |
1138 | void device_release_driver_internal(struct device *dev, |
1139 | struct device_driver *drv, | |
1140 | struct device *parent) | |
4bdb3550 | 1141 | { |
ed88747c | 1142 | __device_driver_lock(dev, parent); |
4bdb3550 | 1143 | |
4bdb3550 | 1144 | if (!drv || drv == dev->driver) |
9ed98953 | 1145 | __device_release_driver(dev, parent); |
4bdb3550 | 1146 | |
ed88747c | 1147 | __device_driver_unlock(dev, parent); |
4bdb3550 RW |
1148 | } |
1149 | ||
ab71c6f0 | 1150 | /** |
4a3ad20c GKH |
1151 | * device_release_driver - manually detach device from driver. |
1152 | * @dev: device. | |
ab71c6f0 | 1153 | * |
4a3ad20c | 1154 | * Manually detach device from driver. |
8e9394ce | 1155 | * When called for a USB interface, @dev->parent lock must be held. |
9ed98953 RW |
1156 | * |
1157 | * If this function is to be called with @dev->parent lock held, ensure that | |
1158 | * the device's consumers are unbound in advance or that their locks can be | |
1159 | * acquired under the @dev->parent lock. | |
ab71c6f0 | 1160 | */ |
4a3ad20c | 1161 | void device_release_driver(struct device *dev) |
94e7b1c5 | 1162 | { |
c95a6b05 AS |
1163 | /* |
1164 | * If anyone calls device_release_driver() recursively from | |
1165 | * within their ->remove callback for the same device, they | |
1166 | * will deadlock right here. | |
1167 | */ | |
4bdb3550 | 1168 | device_release_driver_internal(dev, NULL, NULL); |
94e7b1c5 | 1169 | } |
4a3ad20c | 1170 | EXPORT_SYMBOL_GPL(device_release_driver); |
c95a6b05 | 1171 | |
ed88747c AD |
1172 | /** |
1173 | * device_driver_detach - detach driver from a specific device | |
1174 | * @dev: device to detach driver from | |
1175 | * | |
1176 | * Detach driver from device. Will acquire both @dev lock and @dev->parent | |
1177 | * lock if needed. | |
1178 | */ | |
1179 | void device_driver_detach(struct device *dev) | |
1180 | { | |
1181 | device_release_driver_internal(dev, NULL, dev->parent); | |
1182 | } | |
1183 | ||
07e4a3e2 PM |
1184 | /** |
1185 | * driver_detach - detach driver from all devices it controls. | |
1186 | * @drv: driver. | |
1187 | */ | |
4a3ad20c | 1188 | void driver_detach(struct device_driver *drv) |
07e4a3e2 | 1189 | { |
8940b4f3 | 1190 | struct device_private *dev_prv; |
4a3ad20c | 1191 | struct device *dev; |
c95a6b05 | 1192 | |
c37d721c AD |
1193 | if (driver_allows_async_probing(drv)) |
1194 | async_synchronize_full(); | |
1195 | ||
c95a6b05 | 1196 | for (;;) { |
e5dd1278 GKH |
1197 | spin_lock(&drv->p->klist_devices.k_lock); |
1198 | if (list_empty(&drv->p->klist_devices.k_list)) { | |
1199 | spin_unlock(&drv->p->klist_devices.k_lock); | |
c95a6b05 AS |
1200 | break; |
1201 | } | |
a3a87d66 | 1202 | dev_prv = list_last_entry(&drv->p->klist_devices.k_list, |
8940b4f3 GKH |
1203 | struct device_private, |
1204 | knode_driver.n_node); | |
1205 | dev = dev_prv->device; | |
c95a6b05 | 1206 | get_device(dev); |
e5dd1278 | 1207 | spin_unlock(&drv->p->klist_devices.k_lock); |
4bdb3550 | 1208 | device_release_driver_internal(dev, drv, dev->parent); |
c95a6b05 AS |
1209 | put_device(dev); |
1210 | } | |
07e4a3e2 | 1211 | } |