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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> |
d090b70e | 30 | #include <linux/slab.h> |
07e4a3e2 PM |
31 | |
32 | #include "base.h" | |
33 | #include "power/power.h" | |
34 | ||
d1c3414c GL |
35 | /* |
36 | * Deferred Probe infrastructure. | |
37 | * | |
38 | * Sometimes driver probe order matters, but the kernel doesn't always have | |
39 | * dependency information which means some drivers will get probed before a | |
40 | * resource it depends on is available. For example, an SDHCI driver may | |
41 | * first need a GPIO line from an i2c GPIO controller before it can be | |
42 | * initialized. If a required resource is not available yet, a driver can | |
43 | * request probing to be deferred by returning -EPROBE_DEFER from its probe hook | |
44 | * | |
45 | * Deferred probe maintains two lists of devices, a pending list and an active | |
46 | * list. A driver returning -EPROBE_DEFER causes the device to be added to the | |
47 | * pending list. A successful driver probe will trigger moving all devices | |
48 | * from the pending to the active list so that the workqueue will eventually | |
49 | * retry them. | |
50 | * | |
51 | * The deferred_probe_mutex must be held any time the deferred_probe_*_list | |
ef8a3fd6 | 52 | * of the (struct device*)->p->deferred_probe pointers are manipulated |
d1c3414c GL |
53 | */ |
54 | static DEFINE_MUTEX(deferred_probe_mutex); | |
55 | static LIST_HEAD(deferred_probe_pending_list); | |
56 | static LIST_HEAD(deferred_probe_active_list); | |
58b116bc | 57 | static atomic_t deferred_trigger_count = ATOMIC_INIT(0); |
28af109a | 58 | static struct dentry *deferred_devices; |
25b4e70d | 59 | static bool initcalls_done; |
d1c3414c | 60 | |
1ea61b68 FT |
61 | /* Save the async probe drivers' name from kernel cmdline */ |
62 | #define ASYNC_DRV_NAMES_MAX_LEN 256 | |
63 | static char async_probe_drv_names[ASYNC_DRV_NAMES_MAX_LEN]; | |
64 | ||
013c074f SG |
65 | /* |
66 | * In some cases, like suspend to RAM or hibernation, It might be reasonable | |
67 | * to prohibit probing of devices as it could be unsafe. | |
68 | * Once defer_all_probes is true all drivers probes will be forcibly deferred. | |
69 | */ | |
70 | static bool defer_all_probes; | |
71 | ||
41575335 | 72 | /* |
d1c3414c GL |
73 | * deferred_probe_work_func() - Retry probing devices in the active list. |
74 | */ | |
75 | static void deferred_probe_work_func(struct work_struct *work) | |
76 | { | |
77 | struct device *dev; | |
ef8a3fd6 | 78 | struct device_private *private; |
d1c3414c GL |
79 | /* |
80 | * This block processes every device in the deferred 'active' list. | |
81 | * Each device is removed from the active list and passed to | |
82 | * bus_probe_device() to re-attempt the probe. The loop continues | |
83 | * until every device in the active list is removed and retried. | |
84 | * | |
85 | * Note: Once the device is removed from the list and the mutex is | |
86 | * released, it is possible for the device get freed by another thread | |
87 | * and cause a illegal pointer dereference. This code uses | |
88 | * get/put_device() to ensure the device structure cannot disappear | |
89 | * from under our feet. | |
90 | */ | |
91 | mutex_lock(&deferred_probe_mutex); | |
92 | while (!list_empty(&deferred_probe_active_list)) { | |
ef8a3fd6 GKH |
93 | private = list_first_entry(&deferred_probe_active_list, |
94 | typeof(*dev->p), deferred_probe); | |
95 | dev = private->device; | |
96 | list_del_init(&private->deferred_probe); | |
d1c3414c GL |
97 | |
98 | get_device(dev); | |
99 | ||
8b0372a2 GKH |
100 | /* |
101 | * Drop the mutex while probing each device; the probe path may | |
102 | * manipulate the deferred list | |
103 | */ | |
d1c3414c | 104 | mutex_unlock(&deferred_probe_mutex); |
8153584e MB |
105 | |
106 | /* | |
107 | * Force the device to the end of the dpm_list since | |
108 | * the PM code assumes that the order we add things to | |
109 | * the list is a good order for suspend but deferred | |
110 | * probe makes that very unsafe. | |
111 | */ | |
494fd7b7 | 112 | device_pm_move_to_tail(dev); |
8153584e | 113 | |
d1c3414c | 114 | dev_dbg(dev, "Retrying from deferred list\n"); |
0a50f61c | 115 | bus_probe_device(dev); |
d1c3414c GL |
116 | mutex_lock(&deferred_probe_mutex); |
117 | ||
118 | put_device(dev); | |
119 | } | |
120 | mutex_unlock(&deferred_probe_mutex); | |
121 | } | |
122 | static DECLARE_WORK(deferred_probe_work, deferred_probe_work_func); | |
123 | ||
e7dd4010 | 124 | void driver_deferred_probe_add(struct device *dev) |
d1c3414c GL |
125 | { |
126 | mutex_lock(&deferred_probe_mutex); | |
ef8a3fd6 | 127 | if (list_empty(&dev->p->deferred_probe)) { |
d1c3414c | 128 | dev_dbg(dev, "Added to deferred list\n"); |
1d29cfa5 | 129 | list_add_tail(&dev->p->deferred_probe, &deferred_probe_pending_list); |
d1c3414c GL |
130 | } |
131 | mutex_unlock(&deferred_probe_mutex); | |
132 | } | |
133 | ||
134 | void driver_deferred_probe_del(struct device *dev) | |
135 | { | |
136 | mutex_lock(&deferred_probe_mutex); | |
ef8a3fd6 | 137 | if (!list_empty(&dev->p->deferred_probe)) { |
d1c3414c | 138 | dev_dbg(dev, "Removed from deferred list\n"); |
ef8a3fd6 | 139 | list_del_init(&dev->p->deferred_probe); |
d090b70e AH |
140 | kfree(dev->p->deferred_probe_reason); |
141 | dev->p->deferred_probe_reason = NULL; | |
d1c3414c GL |
142 | } |
143 | mutex_unlock(&deferred_probe_mutex); | |
144 | } | |
145 | ||
146 | static bool driver_deferred_probe_enable = false; | |
147 | /** | |
148 | * driver_deferred_probe_trigger() - Kick off re-probing deferred devices | |
149 | * | |
150 | * This functions moves all devices from the pending list to the active | |
151 | * list and schedules the deferred probe workqueue to process them. It | |
152 | * should be called anytime a driver is successfully bound to a device. | |
58b116bc GL |
153 | * |
154 | * Note, there is a race condition in multi-threaded probe. In the case where | |
155 | * more than one device is probing at the same time, it is possible for one | |
156 | * probe to complete successfully while another is about to defer. If the second | |
157 | * depends on the first, then it will get put on the pending list after the | |
9ba8af66 | 158 | * trigger event has already occurred and will be stuck there. |
58b116bc GL |
159 | * |
160 | * The atomic 'deferred_trigger_count' is used to determine if a successful | |
161 | * trigger has occurred in the midst of probing a driver. If the trigger count | |
162 | * changes in the midst of a probe, then deferred processing should be triggered | |
163 | * again. | |
d1c3414c GL |
164 | */ |
165 | static void driver_deferred_probe_trigger(void) | |
716a7a25 SK |
166 | { |
167 | if (!driver_deferred_probe_enable) | |
168 | return; | |
169 | ||
8b0372a2 GKH |
170 | /* |
171 | * A successful probe means that all the devices in the pending list | |
d1c3414c | 172 | * should be triggered to be reprobed. Move all the deferred devices |
8b0372a2 GKH |
173 | * into the active list so they can be retried by the workqueue |
174 | */ | |
d1c3414c | 175 | mutex_lock(&deferred_probe_mutex); |
58b116bc | 176 | atomic_inc(&deferred_trigger_count); |
d1c3414c GL |
177 | list_splice_tail_init(&deferred_probe_pending_list, |
178 | &deferred_probe_active_list); | |
179 | mutex_unlock(&deferred_probe_mutex); | |
180 | ||
8b0372a2 GKH |
181 | /* |
182 | * Kick the re-probe thread. It may already be scheduled, but it is | |
183 | * safe to kick it again. | |
184 | */ | |
2c507e46 | 185 | schedule_work(&deferred_probe_work); |
d1c3414c GL |
186 | } |
187 | ||
013c074f | 188 | /** |
dbf03d65 | 189 | * device_block_probing() - Block/defer device's probes |
013c074f SG |
190 | * |
191 | * It will disable probing of devices and defer their probes instead. | |
192 | */ | |
193 | void device_block_probing(void) | |
194 | { | |
195 | defer_all_probes = true; | |
196 | /* sync with probes to avoid races. */ | |
197 | wait_for_device_probe(); | |
198 | } | |
199 | ||
200 | /** | |
201 | * device_unblock_probing() - Unblock/enable device's probes | |
202 | * | |
203 | * It will restore normal behavior and trigger re-probing of deferred | |
204 | * devices. | |
205 | */ | |
206 | void device_unblock_probing(void) | |
207 | { | |
208 | defer_all_probes = false; | |
209 | driver_deferred_probe_trigger(); | |
210 | } | |
211 | ||
d090b70e AH |
212 | /** |
213 | * device_set_deferred_probe_reason() - Set defer probe reason message for device | |
214 | * @dev: the pointer to the struct device | |
215 | * @vaf: the pointer to va_format structure with message | |
216 | */ | |
217 | void device_set_deferred_probe_reason(const struct device *dev, struct va_format *vaf) | |
218 | { | |
219 | const char *drv = dev_driver_string(dev); | |
220 | ||
221 | mutex_lock(&deferred_probe_mutex); | |
222 | ||
223 | kfree(dev->p->deferred_probe_reason); | |
224 | dev->p->deferred_probe_reason = kasprintf(GFP_KERNEL, "%s: %pV", drv, vaf); | |
225 | ||
226 | mutex_unlock(&deferred_probe_mutex); | |
227 | } | |
228 | ||
28af109a JMC |
229 | /* |
230 | * deferred_devs_show() - Show the devices in the deferred probe pending list. | |
231 | */ | |
232 | static int deferred_devs_show(struct seq_file *s, void *data) | |
233 | { | |
234 | struct device_private *curr; | |
235 | ||
236 | mutex_lock(&deferred_probe_mutex); | |
237 | ||
238 | list_for_each_entry(curr, &deferred_probe_pending_list, deferred_probe) | |
d090b70e AH |
239 | seq_printf(s, "%s\t%s", dev_name(curr->device), |
240 | curr->device->p->deferred_probe_reason ?: "\n"); | |
28af109a JMC |
241 | |
242 | mutex_unlock(&deferred_probe_mutex); | |
243 | ||
244 | return 0; | |
245 | } | |
246 | DEFINE_SHOW_ATTRIBUTE(deferred_devs); | |
247 | ||
ce68929f | 248 | int driver_deferred_probe_timeout; |
64c775fb | 249 | EXPORT_SYMBOL_GPL(driver_deferred_probe_timeout); |
35a67236 | 250 | static DECLARE_WAIT_QUEUE_HEAD(probe_timeout_waitqueue); |
64c775fb | 251 | |
25b4e70d RH |
252 | static int __init deferred_probe_timeout_setup(char *str) |
253 | { | |
63c98047 MS |
254 | int timeout; |
255 | ||
256 | if (!kstrtoint(str, 10, &timeout)) | |
64c775fb | 257 | driver_deferred_probe_timeout = timeout; |
25b4e70d RH |
258 | return 1; |
259 | } | |
260 | __setup("deferred_probe_timeout=", deferred_probe_timeout_setup); | |
261 | ||
262 | /** | |
263 | * driver_deferred_probe_check_state() - Check deferred probe state | |
264 | * @dev: device to check | |
265 | * | |
c8c43cee JS |
266 | * Return: |
267 | * -ENODEV if initcalls have completed and modules are disabled. | |
268 | * -ETIMEDOUT if the deferred probe timeout was set and has expired | |
269 | * and modules are enabled. | |
270 | * -EPROBE_DEFER in other cases. | |
25b4e70d RH |
271 | * |
272 | * Drivers or subsystems can opt-in to calling this function instead of directly | |
273 | * returning -EPROBE_DEFER. | |
274 | */ | |
275 | int driver_deferred_probe_check_state(struct device *dev) | |
276 | { | |
0e9f8d09 | 277 | if (!IS_ENABLED(CONFIG_MODULES) && initcalls_done) { |
eb7fbc9f | 278 | dev_warn(dev, "ignoring dependency for device, assuming no driver\n"); |
0e9f8d09 JS |
279 | return -ENODEV; |
280 | } | |
62a6bc3a | 281 | |
ce68929f | 282 | if (!driver_deferred_probe_timeout && initcalls_done) { |
c8be6af9 | 283 | dev_warn(dev, "deferred probe timeout, ignoring dependency\n"); |
0e9f8d09 JS |
284 | return -ETIMEDOUT; |
285 | } | |
62a6bc3a | 286 | |
25b4e70d RH |
287 | return -EPROBE_DEFER; |
288 | } | |
289 | ||
290 | static void deferred_probe_timeout_work_func(struct work_struct *work) | |
291 | { | |
292 | struct device_private *private, *p; | |
293 | ||
64c775fb | 294 | driver_deferred_probe_timeout = 0; |
25b4e70d RH |
295 | driver_deferred_probe_trigger(); |
296 | flush_work(&deferred_probe_work); | |
297 | ||
298 | list_for_each_entry_safe(private, p, &deferred_probe_pending_list, deferred_probe) | |
eb7fbc9f | 299 | dev_info(private->device, "deferred probe pending\n"); |
b292b50b | 300 | wake_up_all(&probe_timeout_waitqueue); |
25b4e70d RH |
301 | } |
302 | static DECLARE_DELAYED_WORK(deferred_probe_timeout_work, deferred_probe_timeout_work_func); | |
303 | ||
d1c3414c GL |
304 | /** |
305 | * deferred_probe_initcall() - Enable probing of deferred devices | |
306 | * | |
307 | * We don't want to get in the way when the bulk of drivers are getting probed. | |
308 | * Instead, this initcall makes sure that deferred probing is delayed until | |
309 | * late_initcall time. | |
310 | */ | |
311 | static int deferred_probe_initcall(void) | |
312 | { | |
28af109a JMC |
313 | deferred_devices = debugfs_create_file("devices_deferred", 0444, NULL, |
314 | NULL, &deferred_devs_fops); | |
315 | ||
d1c3414c GL |
316 | driver_deferred_probe_enable = true; |
317 | driver_deferred_probe_trigger(); | |
d72cca1e | 318 | /* Sort as many dependencies as possible before exiting initcalls */ |
2c507e46 | 319 | flush_work(&deferred_probe_work); |
25b4e70d RH |
320 | initcalls_done = true; |
321 | ||
322 | /* | |
323 | * Trigger deferred probe again, this time we won't defer anything | |
324 | * that is optional | |
325 | */ | |
326 | driver_deferred_probe_trigger(); | |
327 | flush_work(&deferred_probe_work); | |
328 | ||
64c775fb | 329 | if (driver_deferred_probe_timeout > 0) { |
25b4e70d | 330 | schedule_delayed_work(&deferred_probe_timeout_work, |
64c775fb | 331 | driver_deferred_probe_timeout * HZ); |
25b4e70d | 332 | } |
d1c3414c GL |
333 | return 0; |
334 | } | |
335 | late_initcall(deferred_probe_initcall); | |
07e4a3e2 | 336 | |
28af109a JMC |
337 | static void __exit deferred_probe_exit(void) |
338 | { | |
339 | debugfs_remove_recursive(deferred_devices); | |
340 | } | |
341 | __exitcall(deferred_probe_exit); | |
342 | ||
6b9cb427 TV |
343 | /** |
344 | * device_is_bound() - Check if device is bound to a driver | |
345 | * @dev: device to check | |
346 | * | |
347 | * Returns true if passed device has already finished probing successfully | |
348 | * against a driver. | |
349 | * | |
350 | * This function must be called with the device lock held. | |
351 | */ | |
352 | bool device_is_bound(struct device *dev) | |
353 | { | |
3ded9104 | 354 | return dev->p && klist_node_attached(&dev->p->knode_driver); |
6b9cb427 TV |
355 | } |
356 | ||
1901fb26 | 357 | static void driver_bound(struct device *dev) |
07e4a3e2 | 358 | { |
6b9cb427 | 359 | if (device_is_bound(dev)) { |
eb7fbc9f | 360 | pr_warn("%s: device %s already bound\n", |
2b3a302a | 361 | __func__, kobject_name(&dev->kobj)); |
1901fb26 | 362 | return; |
f86db396 | 363 | } |
4c898c7f | 364 | |
94f8cc0e FR |
365 | pr_debug("driver: '%s': %s: bound to device '%s'\n", dev->driver->name, |
366 | __func__, dev_name(dev)); | |
116af378 | 367 | |
fbb88fad | 368 | klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices); |
9ed98953 | 369 | device_links_driver_bound(dev); |
fbb88fad | 370 | |
aa8e54b5 TV |
371 | device_pm_check_callbacks(dev); |
372 | ||
8b0372a2 GKH |
373 | /* |
374 | * Make sure the device is no longer in one of the deferred lists and | |
375 | * kick off retrying all pending devices | |
376 | */ | |
d1c3414c GL |
377 | driver_deferred_probe_del(dev); |
378 | driver_deferred_probe_trigger(); | |
379 | ||
116af378 | 380 | if (dev->bus) |
c6f7e72a | 381 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
116af378 | 382 | BUS_NOTIFY_BOUND_DRIVER, dev); |
1455cf8d DT |
383 | |
384 | kobject_uevent(&dev->kobj, KOBJ_BIND); | |
1901fb26 KS |
385 | } |
386 | ||
3c47d19f AS |
387 | static ssize_t coredump_store(struct device *dev, struct device_attribute *attr, |
388 | const char *buf, size_t count) | |
389 | { | |
390 | device_lock(dev); | |
1fe56e0c | 391 | dev->driver->coredump(dev); |
3c47d19f AS |
392 | device_unlock(dev); |
393 | ||
394 | return count; | |
395 | } | |
396 | static DEVICE_ATTR_WO(coredump); | |
397 | ||
1901fb26 KS |
398 | static int driver_sysfs_add(struct device *dev) |
399 | { | |
400 | int ret; | |
401 | ||
45daef0f MD |
402 | if (dev->bus) |
403 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
404 | BUS_NOTIFY_BIND_DRIVER, dev); | |
405 | ||
e5dd1278 | 406 | ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj, |
3c47d19f AS |
407 | kobject_name(&dev->kobj)); |
408 | if (ret) | |
409 | goto fail; | |
410 | ||
411 | ret = sysfs_create_link(&dev->kobj, &dev->driver->p->kobj, | |
412 | "driver"); | |
413 | if (ret) | |
414 | goto rm_dev; | |
415 | ||
416 | if (!IS_ENABLED(CONFIG_DEV_COREDUMP) || !dev->driver->coredump || | |
417 | !device_create_file(dev, &dev_attr_coredump)) | |
418 | return 0; | |
419 | ||
420 | sysfs_remove_link(&dev->kobj, "driver"); | |
421 | ||
422 | rm_dev: | |
423 | sysfs_remove_link(&dev->driver->p->kobj, | |
07e4a3e2 | 424 | kobject_name(&dev->kobj)); |
3c47d19f AS |
425 | |
426 | fail: | |
f86db396 | 427 | return ret; |
07e4a3e2 PM |
428 | } |
429 | ||
1901fb26 KS |
430 | static void driver_sysfs_remove(struct device *dev) |
431 | { | |
432 | struct device_driver *drv = dev->driver; | |
433 | ||
434 | if (drv) { | |
3c47d19f AS |
435 | if (drv->coredump) |
436 | device_remove_file(dev, &dev_attr_coredump); | |
e5dd1278 | 437 | sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj)); |
1901fb26 KS |
438 | sysfs_remove_link(&dev->kobj, "driver"); |
439 | } | |
440 | } | |
441 | ||
442 | /** | |
4a3ad20c GKH |
443 | * device_bind_driver - bind a driver to one device. |
444 | * @dev: device. | |
1901fb26 | 445 | * |
4a3ad20c GKH |
446 | * Allow manual attachment of a driver to a device. |
447 | * Caller must have already set @dev->driver. | |
1901fb26 | 448 | * |
fe940d73 LW |
449 | * Note that this does not modify the bus reference count. |
450 | * Please verify that is accounted for before calling this. | |
451 | * (It is ok to call with no other effort from a driver's probe() method.) | |
1901fb26 | 452 | * |
8e9394ce | 453 | * This function must be called with the device lock held. |
1901fb26 KS |
454 | */ |
455 | int device_bind_driver(struct device *dev) | |
456 | { | |
cb986b74 CH |
457 | int ret; |
458 | ||
459 | ret = driver_sysfs_add(dev); | |
460 | if (!ret) | |
461 | driver_bound(dev); | |
14b6257a AS |
462 | else if (dev->bus) |
463 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
464 | BUS_NOTIFY_DRIVER_NOT_BOUND, dev); | |
cb986b74 | 465 | return ret; |
1901fb26 | 466 | } |
4a3ad20c | 467 | EXPORT_SYMBOL_GPL(device_bind_driver); |
1901fb26 | 468 | |
d779249e | 469 | static atomic_t probe_count = ATOMIC_INIT(0); |
735a7ffb AM |
470 | static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue); |
471 | ||
0ff26c66 AH |
472 | static void driver_deferred_probe_add_trigger(struct device *dev, |
473 | int local_trigger_count) | |
474 | { | |
475 | driver_deferred_probe_add(dev); | |
476 | /* Did a trigger occur while probing? Need to re-trigger if yes */ | |
477 | if (local_trigger_count != atomic_read(&deferred_trigger_count)) | |
478 | driver_deferred_probe_trigger(); | |
479 | } | |
480 | ||
8fd456ec SK |
481 | static ssize_t state_synced_show(struct device *dev, |
482 | struct device_attribute *attr, char *buf) | |
483 | { | |
484 | bool val; | |
485 | ||
486 | device_lock(dev); | |
487 | val = dev->state_synced; | |
488 | device_unlock(dev); | |
948b3edb | 489 | |
aa838896 | 490 | return sysfs_emit(buf, "%u\n", val); |
8fd456ec SK |
491 | } |
492 | static DEVICE_ATTR_RO(state_synced); | |
493 | ||
21c7f30b | 494 | static int really_probe(struct device *dev, struct device_driver *drv) |
07e4a3e2 | 495 | { |
013c074f | 496 | int ret = -EPROBE_DEFER; |
58b116bc | 497 | int local_trigger_count = atomic_read(&deferred_trigger_count); |
c5f06274 RH |
498 | bool test_remove = IS_ENABLED(CONFIG_DEBUG_TEST_DRIVER_REMOVE) && |
499 | !drv->suppress_bind_attrs; | |
07e4a3e2 | 500 | |
013c074f SG |
501 | if (defer_all_probes) { |
502 | /* | |
503 | * Value of defer_all_probes can be set only by | |
dbf03d65 | 504 | * device_block_probing() which, in turn, will call |
013c074f SG |
505 | * wait_for_device_probe() right after that to avoid any races. |
506 | */ | |
507 | dev_dbg(dev, "Driver %s force probe deferral\n", drv->name); | |
508 | driver_deferred_probe_add(dev); | |
509 | return ret; | |
510 | } | |
511 | ||
9ed98953 | 512 | ret = device_links_check_suppliers(dev); |
0ff26c66 AH |
513 | if (ret == -EPROBE_DEFER) |
514 | driver_deferred_probe_add_trigger(dev, local_trigger_count); | |
9ed98953 RW |
515 | if (ret) |
516 | return ret; | |
517 | ||
d779249e | 518 | atomic_inc(&probe_count); |
7dc72b28 | 519 | pr_debug("bus: '%s': %s: probing driver %s with device %s\n", |
1e0b2cf9 | 520 | drv->bus->name, __func__, drv->name, dev_name(dev)); |
7c35e699 GU |
521 | if (!list_empty(&dev->devres_head)) { |
522 | dev_crit(dev, "Resources present before probing\n"); | |
b292b50b TH |
523 | ret = -EBUSY; |
524 | goto done; | |
7c35e699 | 525 | } |
07e4a3e2 | 526 | |
bea5b158 | 527 | re_probe: |
07e4a3e2 | 528 | dev->driver = drv; |
ab78029e LW |
529 | |
530 | /* If using pinctrl, bind pins now before probing */ | |
531 | ret = pinctrl_bind_pins(dev); | |
532 | if (ret) | |
14b6257a | 533 | goto pinctrl_bind_failed; |
ab78029e | 534 | |
ccf640f4 CH |
535 | if (dev->bus->dma_configure) { |
536 | ret = dev->bus->dma_configure(dev); | |
537 | if (ret) | |
0b777eee | 538 | goto probe_failed; |
ccf640f4 | 539 | } |
09515ef5 | 540 | |
1901fb26 | 541 | if (driver_sysfs_add(dev)) { |
eb7fbc9f CJ |
542 | pr_err("%s: driver_sysfs_add(%s) failed\n", |
543 | __func__, dev_name(dev)); | |
1901fb26 KS |
544 | goto probe_failed; |
545 | } | |
546 | ||
e90d5532 RW |
547 | if (dev->pm_domain && dev->pm_domain->activate) { |
548 | ret = dev->pm_domain->activate(dev); | |
549 | if (ret) | |
550 | goto probe_failed; | |
551 | } | |
552 | ||
594c8281 RK |
553 | if (dev->bus->probe) { |
554 | ret = dev->bus->probe(dev); | |
1901fb26 | 555 | if (ret) |
d779249e | 556 | goto probe_failed; |
594c8281 | 557 | } else if (drv->probe) { |
0d3e5a2e | 558 | ret = drv->probe(dev); |
1901fb26 | 559 | if (ret) |
d779249e | 560 | goto probe_failed; |
f86db396 | 561 | } |
1901fb26 | 562 | |
23b69044 DT |
563 | if (device_add_groups(dev, drv->dev_groups)) { |
564 | dev_err(dev, "device_add_groups() failed\n"); | |
565 | goto dev_groups_failed; | |
566 | } | |
567 | ||
8fd456ec SK |
568 | if (dev_has_sync_state(dev) && |
569 | device_create_file(dev, &dev_attr_state_synced)) { | |
570 | dev_err(dev, "state_synced sysfs add failed\n"); | |
571 | goto dev_sysfs_state_synced_failed; | |
572 | } | |
573 | ||
bea5b158 RH |
574 | if (test_remove) { |
575 | test_remove = false; | |
576 | ||
8fd456ec | 577 | device_remove_file(dev, &dev_attr_state_synced); |
23b69044 DT |
578 | device_remove_groups(dev, drv->dev_groups); |
579 | ||
bdacd1b4 | 580 | if (dev->bus->remove) |
bea5b158 RH |
581 | dev->bus->remove(dev); |
582 | else if (drv->remove) | |
583 | drv->remove(dev); | |
584 | ||
585 | devres_release_all(dev); | |
586 | driver_sysfs_remove(dev); | |
587 | dev->driver = NULL; | |
588 | dev_set_drvdata(dev, NULL); | |
589 | if (dev->pm_domain && dev->pm_domain->dismiss) | |
590 | dev->pm_domain->dismiss(dev); | |
591 | pm_runtime_reinit(dev); | |
592 | ||
593 | goto re_probe; | |
594 | } | |
595 | ||
ef0eebc0 DA |
596 | pinctrl_init_done(dev); |
597 | ||
e90d5532 RW |
598 | if (dev->pm_domain && dev->pm_domain->sync) |
599 | dev->pm_domain->sync(dev); | |
600 | ||
1901fb26 | 601 | driver_bound(dev); |
0d3e5a2e | 602 | ret = 1; |
7dc72b28 | 603 | pr_debug("bus: '%s': %s: bound device %s to driver %s\n", |
1e0b2cf9 | 604 | drv->bus->name, __func__, dev_name(dev), drv->name); |
d779249e | 605 | goto done; |
0d3e5a2e | 606 | |
8fd456ec SK |
607 | dev_sysfs_state_synced_failed: |
608 | device_remove_groups(dev, drv->dev_groups); | |
23b69044 DT |
609 | dev_groups_failed: |
610 | if (dev->bus->remove) | |
611 | dev->bus->remove(dev); | |
612 | else if (drv->remove) | |
613 | drv->remove(dev); | |
d779249e | 614 | probe_failed: |
14b6257a AS |
615 | if (dev->bus) |
616 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
617 | BUS_NOTIFY_DRIVER_NOT_BOUND, dev); | |
618 | pinctrl_bind_failed: | |
9ed98953 | 619 | device_links_no_driver(dev); |
9ac7849e | 620 | devres_release_all(dev); |
0b777eee | 621 | arch_teardown_dma_ops(dev); |
1901fb26 KS |
622 | driver_sysfs_remove(dev); |
623 | dev->driver = NULL; | |
0998d063 | 624 | dev_set_drvdata(dev, NULL); |
e90d5532 RW |
625 | if (dev->pm_domain && dev->pm_domain->dismiss) |
626 | dev->pm_domain->dismiss(dev); | |
5de85b9d | 627 | pm_runtime_reinit(dev); |
08810a41 | 628 | dev_pm_set_driver_flags(dev, 0); |
1901fb26 | 629 | |
bb2b4075 SS |
630 | switch (ret) { |
631 | case -EPROBE_DEFER: | |
d1c3414c | 632 | /* Driver requested deferred probing */ |
13fcffbb | 633 | dev_dbg(dev, "Driver %s requests probe deferral\n", drv->name); |
0ff26c66 | 634 | driver_deferred_probe_add_trigger(dev, local_trigger_count); |
bb2b4075 SS |
635 | break; |
636 | case -ENODEV: | |
637 | case -ENXIO: | |
638 | pr_debug("%s: probe of %s rejects match %d\n", | |
639 | drv->name, dev_name(dev), ret); | |
640 | break; | |
641 | default: | |
0d3e5a2e | 642 | /* driver matched but the probe failed */ |
eb7fbc9f CJ |
643 | pr_warn("%s: probe of %s failed with error %d\n", |
644 | drv->name, dev_name(dev), ret); | |
0d3e5a2e | 645 | } |
c578abbc CH |
646 | /* |
647 | * Ignore errors returned by ->probe so that the next driver can try | |
648 | * its luck. | |
649 | */ | |
650 | ret = 0; | |
d779249e | 651 | done: |
d779249e | 652 | atomic_dec(&probe_count); |
b292b50b | 653 | wake_up_all(&probe_waitqueue); |
d779249e GKH |
654 | return ret; |
655 | } | |
656 | ||
0a50f61c TP |
657 | /* |
658 | * For initcall_debug, show the driver probe time. | |
659 | */ | |
660 | static int really_probe_debug(struct device *dev, struct device_driver *drv) | |
661 | { | |
e3aa745f | 662 | ktime_t calltime, rettime; |
0a50f61c TP |
663 | int ret; |
664 | ||
665 | calltime = ktime_get(); | |
666 | ret = really_probe(dev, drv); | |
667 | rettime = ktime_get(); | |
eb7fbc9f | 668 | pr_debug("probe of %s returned %d after %lld usecs\n", |
e3aa745f | 669 | dev_name(dev), ret, ktime_us_delta(rettime, calltime)); |
0a50f61c TP |
670 | return ret; |
671 | } | |
672 | ||
d779249e GKH |
673 | /** |
674 | * driver_probe_done | |
675 | * Determine if the probe sequence is finished or not. | |
676 | * | |
677 | * Should somehow figure out how to use a semaphore, not an atomic variable... | |
678 | */ | |
679 | int driver_probe_done(void) | |
680 | { | |
927f8287 AS |
681 | int local_probe_count = atomic_read(&probe_count); |
682 | ||
683 | pr_debug("%s: probe_count = %d\n", __func__, local_probe_count); | |
684 | if (local_probe_count) | |
d779249e GKH |
685 | return -EBUSY; |
686 | return 0; | |
687 | } | |
688 | ||
216773a7 AV |
689 | /** |
690 | * wait_for_device_probe | |
691 | * Wait for device probing to be completed. | |
216773a7 | 692 | */ |
b23530eb | 693 | void wait_for_device_probe(void) |
216773a7 | 694 | { |
35a67236 JS |
695 | /* wait for probe timeout */ |
696 | wait_event(probe_timeout_waitqueue, !driver_deferred_probe_timeout); | |
697 | ||
013c074f | 698 | /* wait for the deferred probe workqueue to finish */ |
2c507e46 | 699 | flush_work(&deferred_probe_work); |
013c074f | 700 | |
216773a7 | 701 | /* wait for the known devices to complete their probing */ |
b23530eb | 702 | wait_event(probe_waitqueue, atomic_read(&probe_count) == 0); |
216773a7 | 703 | async_synchronize_full(); |
216773a7 | 704 | } |
d4d5291c | 705 | EXPORT_SYMBOL_GPL(wait_for_device_probe); |
216773a7 | 706 | |
d779249e GKH |
707 | /** |
708 | * driver_probe_device - attempt to bind device & driver together | |
709 | * @drv: driver to bind a device to | |
710 | * @dev: device to try to bind to the driver | |
711 | * | |
49b420a1 | 712 | * This function returns -ENODEV if the device is not registered, |
af901ca1 | 713 | * 1 if the device is bound successfully and 0 otherwise. |
d779249e | 714 | * |
8e9394ce GKH |
715 | * This function must be called with @dev lock held. When called for a |
716 | * USB interface, @dev->parent lock must be held as well. | |
ddef08dd RW |
717 | * |
718 | * If the device has a parent, runtime-resume the parent before driver probing. | |
d779249e | 719 | */ |
4a3ad20c | 720 | int driver_probe_device(struct device_driver *drv, struct device *dev) |
d779249e | 721 | { |
d779249e GKH |
722 | int ret = 0; |
723 | ||
f2eaae19 AS |
724 | if (!device_is_registered(dev)) |
725 | return -ENODEV; | |
d779249e | 726 | |
7dc72b28 | 727 | pr_debug("bus: '%s': %s: matched device %s with driver %s\n", |
1e0b2cf9 | 728 | drv->bus->name, __func__, dev_name(dev), drv->name); |
d779249e | 729 | |
b06c0b2f | 730 | pm_runtime_get_suppliers(dev); |
ddef08dd RW |
731 | if (dev->parent) |
732 | pm_runtime_get_sync(dev->parent); | |
733 | ||
5e928f77 | 734 | pm_runtime_barrier(dev); |
0a50f61c TP |
735 | if (initcall_debug) |
736 | ret = really_probe_debug(dev, drv); | |
737 | else | |
738 | ret = really_probe(dev, drv); | |
fa180eb4 | 739 | pm_request_idle(dev); |
d779249e | 740 | |
ddef08dd RW |
741 | if (dev->parent) |
742 | pm_runtime_put(dev->parent); | |
743 | ||
b06c0b2f | 744 | pm_runtime_put_suppliers(dev); |
0d3e5a2e | 745 | return ret; |
07e4a3e2 PM |
746 | } |
747 | ||
1ea61b68 FT |
748 | static inline bool cmdline_requested_async_probing(const char *drv_name) |
749 | { | |
750 | return parse_option_str(async_probe_drv_names, drv_name); | |
751 | } | |
752 | ||
753 | /* The option format is "driver_async_probe=drv_name1,drv_name2,..." */ | |
754 | static int __init save_async_options(char *buf) | |
755 | { | |
756 | if (strlen(buf) >= ASYNC_DRV_NAMES_MAX_LEN) | |
eb7fbc9f | 757 | pr_warn("Too long list of driver names for 'driver_async_probe'!\n"); |
1ea61b68 FT |
758 | |
759 | strlcpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN); | |
760 | return 0; | |
761 | } | |
762 | __setup("driver_async_probe=", save_async_options); | |
763 | ||
765230b5 | 764 | bool driver_allows_async_probing(struct device_driver *drv) |
2287c322 | 765 | { |
d173a137 LR |
766 | switch (drv->probe_type) { |
767 | case PROBE_PREFER_ASYNCHRONOUS: | |
f2411da7 LR |
768 | return true; |
769 | ||
d173a137 LR |
770 | case PROBE_FORCE_SYNCHRONOUS: |
771 | return false; | |
772 | ||
773 | default: | |
1ea61b68 FT |
774 | if (cmdline_requested_async_probing(drv->name)) |
775 | return true; | |
776 | ||
80c6e146 | 777 | if (module_requested_async_probing(drv->owner)) |
d173a137 | 778 | return true; |
f2411da7 | 779 | |
d173a137 LR |
780 | return false; |
781 | } | |
765230b5 DT |
782 | } |
783 | ||
784 | struct device_attach_data { | |
785 | struct device *dev; | |
786 | ||
787 | /* | |
788 | * Indicates whether we are are considering asynchronous probing or | |
789 | * not. Only initial binding after device or driver registration | |
790 | * (including deferral processing) may be done asynchronously, the | |
791 | * rest is always synchronous, as we expect it is being done by | |
792 | * request from userspace. | |
793 | */ | |
794 | bool check_async; | |
795 | ||
796 | /* | |
797 | * Indicates if we are binding synchronous or asynchronous drivers. | |
798 | * When asynchronous probing is enabled we'll execute 2 passes | |
799 | * over drivers: first pass doing synchronous probing and second | |
800 | * doing asynchronous probing (if synchronous did not succeed - | |
801 | * most likely because there was no driver requiring synchronous | |
802 | * probing - and we found asynchronous driver during first pass). | |
803 | * The 2 passes are done because we can't shoot asynchronous | |
804 | * probe for given device and driver from bus_for_each_drv() since | |
805 | * driver pointer is not guaranteed to stay valid once | |
806 | * bus_for_each_drv() iterates to the next driver on the bus. | |
807 | */ | |
808 | bool want_async; | |
809 | ||
810 | /* | |
811 | * We'll set have_async to 'true' if, while scanning for matching | |
812 | * driver, we'll encounter one that requests asynchronous probing. | |
813 | */ | |
814 | bool have_async; | |
815 | }; | |
816 | ||
817 | static int __device_attach_driver(struct device_driver *drv, void *_data) | |
818 | { | |
819 | struct device_attach_data *data = _data; | |
820 | struct device *dev = data->dev; | |
821 | bool async_allowed; | |
656b8035 | 822 | int ret; |
765230b5 | 823 | |
656b8035 TV |
824 | ret = driver_match_device(drv, dev); |
825 | if (ret == 0) { | |
826 | /* no match */ | |
49b420a1 | 827 | return 0; |
656b8035 TV |
828 | } else if (ret == -EPROBE_DEFER) { |
829 | dev_dbg(dev, "Device match requests probe deferral\n"); | |
830 | driver_deferred_probe_add(dev); | |
831 | } else if (ret < 0) { | |
eb7fbc9f | 832 | dev_dbg(dev, "Bus failed to match device: %d\n", ret); |
656b8035 TV |
833 | return ret; |
834 | } /* ret > 0 means positive match */ | |
49b420a1 | 835 | |
765230b5 DT |
836 | async_allowed = driver_allows_async_probing(drv); |
837 | ||
838 | if (async_allowed) | |
839 | data->have_async = true; | |
840 | ||
841 | if (data->check_async && async_allowed != data->want_async) | |
842 | return 0; | |
843 | ||
0d3e5a2e | 844 | return driver_probe_device(drv, dev); |
2287c322 PM |
845 | } |
846 | ||
765230b5 DT |
847 | static void __device_attach_async_helper(void *_dev, async_cookie_t cookie) |
848 | { | |
849 | struct device *dev = _dev; | |
850 | struct device_attach_data data = { | |
851 | .dev = dev, | |
852 | .check_async = true, | |
853 | .want_async = true, | |
854 | }; | |
855 | ||
856 | device_lock(dev); | |
857 | ||
3451a495 AD |
858 | /* |
859 | * Check if device has already been removed or claimed. This may | |
860 | * happen with driver loading, device discovery/registration, | |
861 | * and deferred probe processing happens all at once with | |
862 | * multiple threads. | |
863 | */ | |
864 | if (dev->p->dead || dev->driver) | |
865 | goto out_unlock; | |
866 | ||
ddef08dd RW |
867 | if (dev->parent) |
868 | pm_runtime_get_sync(dev->parent); | |
869 | ||
765230b5 DT |
870 | bus_for_each_drv(dev->bus, NULL, &data, __device_attach_driver); |
871 | dev_dbg(dev, "async probe completed\n"); | |
872 | ||
873 | pm_request_idle(dev); | |
874 | ||
ddef08dd RW |
875 | if (dev->parent) |
876 | pm_runtime_put(dev->parent); | |
3451a495 | 877 | out_unlock: |
765230b5 DT |
878 | device_unlock(dev); |
879 | ||
880 | put_device(dev); | |
881 | } | |
882 | ||
802a87fd | 883 | static int __device_attach(struct device *dev, bool allow_async) |
07e4a3e2 | 884 | { |
0d3e5a2e PM |
885 | int ret = 0; |
886 | ||
8e9394ce | 887 | device_lock(dev); |
65488832 LW |
888 | if (dev->p->dead) { |
889 | goto out_unlock; | |
890 | } else if (dev->driver) { | |
6b9cb427 | 891 | if (device_is_bound(dev)) { |
8497d6a2 SO |
892 | ret = 1; |
893 | goto out_unlock; | |
894 | } | |
f86db396 AM |
895 | ret = device_bind_driver(dev); |
896 | if (ret == 0) | |
897 | ret = 1; | |
c6a46696 CH |
898 | else { |
899 | dev->driver = NULL; | |
900 | ret = 0; | |
901 | } | |
21c7f30b | 902 | } else { |
765230b5 DT |
903 | struct device_attach_data data = { |
904 | .dev = dev, | |
905 | .check_async = allow_async, | |
906 | .want_async = false, | |
907 | }; | |
908 | ||
ddef08dd RW |
909 | if (dev->parent) |
910 | pm_runtime_get_sync(dev->parent); | |
911 | ||
765230b5 DT |
912 | ret = bus_for_each_drv(dev->bus, NULL, &data, |
913 | __device_attach_driver); | |
914 | if (!ret && allow_async && data.have_async) { | |
915 | /* | |
916 | * If we could not find appropriate driver | |
917 | * synchronously and we are allowed to do | |
918 | * async probes and there are drivers that | |
919 | * want to probe asynchronously, we'll | |
920 | * try them. | |
921 | */ | |
922 | dev_dbg(dev, "scheduling asynchronous probe\n"); | |
923 | get_device(dev); | |
c37e20ea | 924 | async_schedule_dev(__device_attach_async_helper, dev); |
765230b5 DT |
925 | } else { |
926 | pm_request_idle(dev); | |
927 | } | |
ddef08dd RW |
928 | |
929 | if (dev->parent) | |
930 | pm_runtime_put(dev->parent); | |
21c7f30b | 931 | } |
8497d6a2 | 932 | out_unlock: |
8e9394ce | 933 | device_unlock(dev); |
0d3e5a2e | 934 | return ret; |
2287c322 | 935 | } |
765230b5 DT |
936 | |
937 | /** | |
938 | * device_attach - try to attach device to a driver. | |
939 | * @dev: device. | |
940 | * | |
941 | * Walk the list of drivers that the bus has and call | |
942 | * driver_probe_device() for each pair. If a compatible | |
943 | * pair is found, break out and return. | |
944 | * | |
945 | * Returns 1 if the device was bound to a driver; | |
946 | * 0 if no matching driver was found; | |
947 | * -ENODEV if the device is not registered. | |
948 | * | |
949 | * When called for a USB interface, @dev->parent lock must be held. | |
950 | */ | |
951 | int device_attach(struct device *dev) | |
952 | { | |
953 | return __device_attach(dev, false); | |
954 | } | |
4a3ad20c | 955 | EXPORT_SYMBOL_GPL(device_attach); |
2287c322 | 956 | |
765230b5 DT |
957 | void device_initial_probe(struct device *dev) |
958 | { | |
959 | __device_attach(dev, true); | |
960 | } | |
961 | ||
ed88747c AD |
962 | /* |
963 | * __device_driver_lock - acquire locks needed to manipulate dev->drv | |
964 | * @dev: Device we will update driver info for | |
965 | * @parent: Parent device. Needed if the bus requires parent lock | |
966 | * | |
967 | * This function will take the required locks for manipulating dev->drv. | |
968 | * Normally this will just be the @dev lock, but when called for a USB | |
969 | * interface, @parent lock will be held as well. | |
970 | */ | |
971 | static void __device_driver_lock(struct device *dev, struct device *parent) | |
972 | { | |
973 | if (parent && dev->bus->need_parent_lock) | |
974 | device_lock(parent); | |
975 | device_lock(dev); | |
976 | } | |
977 | ||
978 | /* | |
979 | * __device_driver_unlock - release locks needed to manipulate dev->drv | |
980 | * @dev: Device we will update driver info for | |
981 | * @parent: Parent device. Needed if the bus requires parent lock | |
982 | * | |
983 | * This function will release the required locks for manipulating dev->drv. | |
984 | * Normally this will just be the the @dev lock, but when called for a | |
985 | * USB interface, @parent lock will be released as well. | |
986 | */ | |
987 | static void __device_driver_unlock(struct device *dev, struct device *parent) | |
988 | { | |
989 | device_unlock(dev); | |
990 | if (parent && dev->bus->need_parent_lock) | |
991 | device_unlock(parent); | |
992 | } | |
993 | ||
994 | /** | |
995 | * device_driver_attach - attach a specific driver to a specific device | |
996 | * @drv: Driver to attach | |
997 | * @dev: Device to attach it to | |
998 | * | |
999 | * Manually attach driver to a device. Will acquire both @dev lock and | |
1000 | * @dev->parent lock if needed. | |
1001 | */ | |
1002 | int device_driver_attach(struct device_driver *drv, struct device *dev) | |
1003 | { | |
1004 | int ret = 0; | |
1005 | ||
1006 | __device_driver_lock(dev, dev->parent); | |
1007 | ||
1008 | /* | |
1009 | * If device has been removed or someone has already successfully | |
1010 | * bound a driver before us just skip the driver probe call. | |
1011 | */ | |
1012 | if (!dev->p->dead && !dev->driver) | |
1013 | ret = driver_probe_device(drv, dev); | |
1014 | ||
1015 | __device_driver_unlock(dev, dev->parent); | |
1016 | ||
1017 | return ret; | |
1018 | } | |
1019 | ||
ef0ff683 AD |
1020 | static void __driver_attach_async_helper(void *_dev, async_cookie_t cookie) |
1021 | { | |
1022 | struct device *dev = _dev; | |
1023 | struct device_driver *drv; | |
1024 | int ret = 0; | |
1025 | ||
1026 | __device_driver_lock(dev, dev->parent); | |
1027 | ||
1028 | drv = dev->p->async_driver; | |
1029 | ||
1030 | /* | |
1031 | * If device has been removed or someone has already successfully | |
1032 | * bound a driver before us just skip the driver probe call. | |
1033 | */ | |
1034 | if (!dev->p->dead && !dev->driver) | |
1035 | ret = driver_probe_device(drv, dev); | |
1036 | ||
1037 | __device_driver_unlock(dev, dev->parent); | |
1038 | ||
1039 | dev_dbg(dev, "driver %s async attach completed: %d\n", drv->name, ret); | |
1040 | ||
1041 | put_device(dev); | |
1042 | } | |
1043 | ||
4a3ad20c | 1044 | static int __driver_attach(struct device *dev, void *data) |
2287c322 | 1045 | { |
4a3ad20c | 1046 | struct device_driver *drv = data; |
656b8035 | 1047 | int ret; |
0d3e5a2e PM |
1048 | |
1049 | /* | |
1050 | * Lock device and try to bind to it. We drop the error | |
1051 | * here and always return 0, because we need to keep trying | |
1052 | * to bind to devices and some drivers will return an error | |
1053 | * simply if it didn't support the device. | |
1054 | * | |
1055 | * driver_probe_device() will spit a warning if there | |
1056 | * is an error. | |
1057 | */ | |
1058 | ||
656b8035 TV |
1059 | ret = driver_match_device(drv, dev); |
1060 | if (ret == 0) { | |
1061 | /* no match */ | |
6cd49586 | 1062 | return 0; |
656b8035 TV |
1063 | } else if (ret == -EPROBE_DEFER) { |
1064 | dev_dbg(dev, "Device match requests probe deferral\n"); | |
1065 | driver_deferred_probe_add(dev); | |
1066 | } else if (ret < 0) { | |
eb7fbc9f | 1067 | dev_dbg(dev, "Bus failed to match device: %d\n", ret); |
656b8035 TV |
1068 | return ret; |
1069 | } /* ret > 0 means positive match */ | |
6cd49586 | 1070 | |
ef0ff683 AD |
1071 | if (driver_allows_async_probing(drv)) { |
1072 | /* | |
1073 | * Instead of probing the device synchronously we will | |
1074 | * probe it asynchronously to allow for more parallelism. | |
1075 | * | |
1076 | * We only take the device lock here in order to guarantee | |
1077 | * that the dev->driver and async_driver fields are protected | |
1078 | */ | |
1079 | dev_dbg(dev, "probing driver %s asynchronously\n", drv->name); | |
1080 | device_lock(dev); | |
1081 | if (!dev->driver) { | |
1082 | get_device(dev); | |
1083 | dev->p->async_driver = drv; | |
c37e20ea | 1084 | async_schedule_dev(__driver_attach_async_helper, dev); |
ef0ff683 AD |
1085 | } |
1086 | device_unlock(dev); | |
1087 | return 0; | |
1088 | } | |
1089 | ||
ed88747c | 1090 | device_driver_attach(drv, dev); |
0d3e5a2e | 1091 | |
07e4a3e2 PM |
1092 | return 0; |
1093 | } | |
1094 | ||
1095 | /** | |
4a3ad20c GKH |
1096 | * driver_attach - try to bind driver to devices. |
1097 | * @drv: driver. | |
07e4a3e2 | 1098 | * |
4a3ad20c GKH |
1099 | * Walk the list of devices that the bus has on it and try to |
1100 | * match the driver with each one. If driver_probe_device() | |
1101 | * returns 0 and the @dev->driver is set, we've found a | |
1102 | * compatible pair. | |
07e4a3e2 | 1103 | */ |
4a3ad20c | 1104 | int driver_attach(struct device_driver *drv) |
07e4a3e2 | 1105 | { |
f86db396 | 1106 | return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach); |
07e4a3e2 | 1107 | } |
4a3ad20c | 1108 | EXPORT_SYMBOL_GPL(driver_attach); |
07e4a3e2 | 1109 | |
ab71c6f0 | 1110 | /* |
8e9394ce GKH |
1111 | * __device_release_driver() must be called with @dev lock held. |
1112 | * When called for a USB interface, @dev->parent lock must be held as well. | |
07e4a3e2 | 1113 | */ |
9ed98953 | 1114 | static void __device_release_driver(struct device *dev, struct device *parent) |
07e4a3e2 | 1115 | { |
4a3ad20c | 1116 | struct device_driver *drv; |
07e4a3e2 | 1117 | |
ef2c5174 | 1118 | drv = dev->driver; |
c95a6b05 | 1119 | if (drv) { |
9ed98953 | 1120 | while (device_links_busy(dev)) { |
ed88747c | 1121 | __device_driver_unlock(dev, parent); |
9ed98953 RW |
1122 | |
1123 | device_links_unbind_consumers(dev); | |
9ed98953 | 1124 | |
ed88747c | 1125 | __device_driver_lock(dev, parent); |
9ed98953 RW |
1126 | /* |
1127 | * A concurrent invocation of the same function might | |
1128 | * have released the driver successfully while this one | |
1129 | * was waiting, so check for that. | |
1130 | */ | |
1131 | if (dev->driver != drv) | |
1132 | return; | |
1133 | } | |
1134 | ||
e1866b33 | 1135 | pm_runtime_get_sync(dev); |
21d5c57b | 1136 | pm_runtime_clean_up_links(dev); |
5e928f77 | 1137 | |
1901fb26 | 1138 | driver_sysfs_remove(dev); |
0d3e5a2e | 1139 | |
116af378 | 1140 | if (dev->bus) |
c6f7e72a | 1141 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
116af378 BH |
1142 | BUS_NOTIFY_UNBIND_DRIVER, |
1143 | dev); | |
1144 | ||
baab52de | 1145 | pm_runtime_put_sync(dev); |
e1866b33 | 1146 | |
8fd456ec | 1147 | device_remove_file(dev, &dev_attr_state_synced); |
23b69044 DT |
1148 | device_remove_groups(dev, drv->dev_groups); |
1149 | ||
0f836ca4 | 1150 | if (dev->bus && dev->bus->remove) |
594c8281 RK |
1151 | dev->bus->remove(dev); |
1152 | else if (drv->remove) | |
0d3e5a2e | 1153 | drv->remove(dev); |
9ed98953 RW |
1154 | |
1155 | device_links_driver_cleanup(dev); | |
09515ef5 | 1156 | |
9ac7849e | 1157 | devres_release_all(dev); |
376991db | 1158 | arch_teardown_dma_ops(dev); |
0d3e5a2e | 1159 | dev->driver = NULL; |
0998d063 | 1160 | dev_set_drvdata(dev, NULL); |
e90d5532 RW |
1161 | if (dev->pm_domain && dev->pm_domain->dismiss) |
1162 | dev->pm_domain->dismiss(dev); | |
5de85b9d | 1163 | pm_runtime_reinit(dev); |
08810a41 | 1164 | dev_pm_set_driver_flags(dev, 0); |
e90d5532 | 1165 | |
8940b4f3 | 1166 | klist_remove(&dev->p->knode_driver); |
aa8e54b5 | 1167 | device_pm_check_callbacks(dev); |
309b7d60 JR |
1168 | if (dev->bus) |
1169 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, | |
1170 | BUS_NOTIFY_UNBOUND_DRIVER, | |
1171 | dev); | |
1455cf8d DT |
1172 | |
1173 | kobject_uevent(&dev->kobj, KOBJ_UNBIND); | |
0d3e5a2e | 1174 | } |
07e4a3e2 PM |
1175 | } |
1176 | ||
9ed98953 RW |
1177 | void device_release_driver_internal(struct device *dev, |
1178 | struct device_driver *drv, | |
1179 | struct device *parent) | |
4bdb3550 | 1180 | { |
ed88747c | 1181 | __device_driver_lock(dev, parent); |
4bdb3550 | 1182 | |
4bdb3550 | 1183 | if (!drv || drv == dev->driver) |
9ed98953 | 1184 | __device_release_driver(dev, parent); |
4bdb3550 | 1185 | |
ed88747c | 1186 | __device_driver_unlock(dev, parent); |
4bdb3550 RW |
1187 | } |
1188 | ||
ab71c6f0 | 1189 | /** |
4a3ad20c GKH |
1190 | * device_release_driver - manually detach device from driver. |
1191 | * @dev: device. | |
ab71c6f0 | 1192 | * |
4a3ad20c | 1193 | * Manually detach device from driver. |
8e9394ce | 1194 | * When called for a USB interface, @dev->parent lock must be held. |
9ed98953 RW |
1195 | * |
1196 | * If this function is to be called with @dev->parent lock held, ensure that | |
1197 | * the device's consumers are unbound in advance or that their locks can be | |
1198 | * acquired under the @dev->parent lock. | |
ab71c6f0 | 1199 | */ |
4a3ad20c | 1200 | void device_release_driver(struct device *dev) |
94e7b1c5 | 1201 | { |
c95a6b05 AS |
1202 | /* |
1203 | * If anyone calls device_release_driver() recursively from | |
1204 | * within their ->remove callback for the same device, they | |
1205 | * will deadlock right here. | |
1206 | */ | |
4bdb3550 | 1207 | device_release_driver_internal(dev, NULL, NULL); |
94e7b1c5 | 1208 | } |
4a3ad20c | 1209 | EXPORT_SYMBOL_GPL(device_release_driver); |
c95a6b05 | 1210 | |
ed88747c AD |
1211 | /** |
1212 | * device_driver_detach - detach driver from a specific device | |
1213 | * @dev: device to detach driver from | |
1214 | * | |
1215 | * Detach driver from device. Will acquire both @dev lock and @dev->parent | |
1216 | * lock if needed. | |
1217 | */ | |
1218 | void device_driver_detach(struct device *dev) | |
1219 | { | |
1220 | device_release_driver_internal(dev, NULL, dev->parent); | |
1221 | } | |
1222 | ||
07e4a3e2 PM |
1223 | /** |
1224 | * driver_detach - detach driver from all devices it controls. | |
1225 | * @drv: driver. | |
1226 | */ | |
4a3ad20c | 1227 | void driver_detach(struct device_driver *drv) |
07e4a3e2 | 1228 | { |
8940b4f3 | 1229 | struct device_private *dev_prv; |
4a3ad20c | 1230 | struct device *dev; |
c95a6b05 | 1231 | |
c37d721c AD |
1232 | if (driver_allows_async_probing(drv)) |
1233 | async_synchronize_full(); | |
1234 | ||
c95a6b05 | 1235 | for (;;) { |
e5dd1278 GKH |
1236 | spin_lock(&drv->p->klist_devices.k_lock); |
1237 | if (list_empty(&drv->p->klist_devices.k_list)) { | |
1238 | spin_unlock(&drv->p->klist_devices.k_lock); | |
c95a6b05 AS |
1239 | break; |
1240 | } | |
a3a87d66 | 1241 | dev_prv = list_last_entry(&drv->p->klist_devices.k_list, |
8940b4f3 GKH |
1242 | struct device_private, |
1243 | knode_driver.n_node); | |
1244 | dev = dev_prv->device; | |
c95a6b05 | 1245 | get_device(dev); |
e5dd1278 | 1246 | spin_unlock(&drv->p->klist_devices.k_lock); |
4bdb3550 | 1247 | device_release_driver_internal(dev, drv, dev->parent); |
c95a6b05 AS |
1248 | put_device(dev); |
1249 | } | |
07e4a3e2 | 1250 | } |