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989d42e8 | 1 | // SPDX-License-Identifier: GPL-2.0 |
07e4a3e2 | 2 | /* |
4a3ad20c | 3 | * drivers/base/dd.c - The core device/driver interactions. |
07e4a3e2 | 4 | * |
4a3ad20c GKH |
5 | * This file contains the (sometimes tricky) code that controls the |
6 | * interactions between devices and drivers, which primarily includes | |
7 | * driver binding and unbinding. | |
07e4a3e2 | 8 | * |
4a3ad20c GKH |
9 | * All of this code used to exist in drivers/base/bus.c, but was |
10 | * relocated to here in the name of compartmentalization (since it wasn't | |
11 | * strictly code just for the 'struct bus_type'. | |
07e4a3e2 | 12 | * |
4a3ad20c GKH |
13 | * Copyright (c) 2002-5 Patrick Mochel |
14 | * Copyright (c) 2002-3 Open Source Development Labs | |
b4028437 GKH |
15 | * Copyright (c) 2007-2009 Greg Kroah-Hartman <gregkh@suse.de> |
16 | * Copyright (c) 2007-2009 Novell Inc. | |
07e4a3e2 | 17 | */ |
18 | ||
28af109a | 19 | #include <linux/debugfs.h> |
07e4a3e2 | 20 | #include <linux/device.h> |
216773a7 | 21 | #include <linux/delay.h> |
0a0f0d8b | 22 | #include <linux/dma-map-ops.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 | 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); |
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]; | |
f79f662e | 63 | static bool async_probe_default; |
1ea61b68 | 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 | ||
72a91f19 AF |
72 | static void __device_set_deferred_probe_reason(const struct device *dev, char *reason) |
73 | { | |
74 | kfree(dev->p->deferred_probe_reason); | |
75 | dev->p->deferred_probe_reason = reason; | |
76 | } | |
77 | ||
41575335 | 78 | /* |
d1c3414c GL |
79 | * deferred_probe_work_func() - Retry probing devices in the active list. |
80 | */ | |
81 | static void deferred_probe_work_func(struct work_struct *work) | |
82 | { | |
83 | struct device *dev; | |
ef8a3fd6 | 84 | struct device_private *private; |
d1c3414c GL |
85 | /* |
86 | * This block processes every device in the deferred 'active' list. | |
87 | * Each device is removed from the active list and passed to | |
88 | * bus_probe_device() to re-attempt the probe. The loop continues | |
89 | * until every device in the active list is removed and retried. | |
90 | * | |
91 | * Note: Once the device is removed from the list and the mutex is | |
92 | * released, it is possible for the device get freed by another thread | |
93 | * and cause a illegal pointer dereference. This code uses | |
94 | * get/put_device() to ensure the device structure cannot disappear | |
95 | * from under our feet. | |
96 | */ | |
97 | mutex_lock(&deferred_probe_mutex); | |
98 | while (!list_empty(&deferred_probe_active_list)) { | |
ef8a3fd6 GKH |
99 | private = list_first_entry(&deferred_probe_active_list, |
100 | typeof(*dev->p), deferred_probe); | |
101 | dev = private->device; | |
102 | list_del_init(&private->deferred_probe); | |
d1c3414c GL |
103 | |
104 | get_device(dev); | |
105 | ||
72a91f19 | 106 | __device_set_deferred_probe_reason(dev, NULL); |
f0acf637 | 107 | |
8b0372a2 GKH |
108 | /* |
109 | * Drop the mutex while probing each device; the probe path may | |
110 | * manipulate the deferred list | |
111 | */ | |
d1c3414c | 112 | mutex_unlock(&deferred_probe_mutex); |
8153584e MB |
113 | |
114 | /* | |
115 | * Force the device to the end of the dpm_list since | |
116 | * the PM code assumes that the order we add things to | |
117 | * the list is a good order for suspend but deferred | |
118 | * probe makes that very unsafe. | |
119 | */ | |
494fd7b7 | 120 | device_pm_move_to_tail(dev); |
8153584e | 121 | |
d1c3414c | 122 | dev_dbg(dev, "Retrying from deferred list\n"); |
0a50f61c | 123 | bus_probe_device(dev); |
d1c3414c GL |
124 | mutex_lock(&deferred_probe_mutex); |
125 | ||
126 | put_device(dev); | |
127 | } | |
128 | mutex_unlock(&deferred_probe_mutex); | |
129 | } | |
130 | static DECLARE_WORK(deferred_probe_work, deferred_probe_work_func); | |
131 | ||
e7dd4010 | 132 | void driver_deferred_probe_add(struct device *dev) |
d1c3414c | 133 | { |
f2db85b6 SK |
134 | if (!dev->can_match) |
135 | return; | |
136 | ||
d1c3414c | 137 | mutex_lock(&deferred_probe_mutex); |
ef8a3fd6 | 138 | if (list_empty(&dev->p->deferred_probe)) { |
d1c3414c | 139 | dev_dbg(dev, "Added to deferred list\n"); |
1d29cfa5 | 140 | list_add_tail(&dev->p->deferred_probe, &deferred_probe_pending_list); |
d1c3414c GL |
141 | } |
142 | mutex_unlock(&deferred_probe_mutex); | |
143 | } | |
144 | ||
145 | void driver_deferred_probe_del(struct device *dev) | |
146 | { | |
147 | mutex_lock(&deferred_probe_mutex); | |
ef8a3fd6 | 148 | if (!list_empty(&dev->p->deferred_probe)) { |
d1c3414c | 149 | dev_dbg(dev, "Removed from deferred list\n"); |
ef8a3fd6 | 150 | list_del_init(&dev->p->deferred_probe); |
72a91f19 | 151 | __device_set_deferred_probe_reason(dev, NULL); |
d1c3414c GL |
152 | } |
153 | mutex_unlock(&deferred_probe_mutex); | |
154 | } | |
155 | ||
90158138 | 156 | static bool driver_deferred_probe_enable; |
d1c3414c GL |
157 | /** |
158 | * driver_deferred_probe_trigger() - Kick off re-probing deferred devices | |
159 | * | |
160 | * This functions moves all devices from the pending list to the active | |
161 | * list and schedules the deferred probe workqueue to process them. It | |
162 | * should be called anytime a driver is successfully bound to a device. | |
58b116bc GL |
163 | * |
164 | * Note, there is a race condition in multi-threaded probe. In the case where | |
165 | * more than one device is probing at the same time, it is possible for one | |
166 | * probe to complete successfully while another is about to defer. If the second | |
167 | * depends on the first, then it will get put on the pending list after the | |
9ba8af66 | 168 | * trigger event has already occurred and will be stuck there. |
58b116bc GL |
169 | * |
170 | * The atomic 'deferred_trigger_count' is used to determine if a successful | |
171 | * trigger has occurred in the midst of probing a driver. If the trigger count | |
172 | * changes in the midst of a probe, then deferred processing should be triggered | |
173 | * again. | |
d1c3414c | 174 | */ |
2f8c3ae8 | 175 | void driver_deferred_probe_trigger(void) |
96d8a916 | 176 | { |
999032ec SK |
177 | if (!driver_deferred_probe_enable) |
178 | return; | |
179 | ||
8b0372a2 GKH |
180 | /* |
181 | * A successful probe means that all the devices in the pending list | |
d1c3414c | 182 | * should be triggered to be reprobed. Move all the deferred devices |
8b0372a2 GKH |
183 | * into the active list so they can be retried by the workqueue |
184 | */ | |
d1c3414c | 185 | mutex_lock(&deferred_probe_mutex); |
58b116bc | 186 | atomic_inc(&deferred_trigger_count); |
d1c3414c GL |
187 | list_splice_tail_init(&deferred_probe_pending_list, |
188 | &deferred_probe_active_list); | |
189 | mutex_unlock(&deferred_probe_mutex); | |
190 | ||
8b0372a2 GKH |
191 | /* |
192 | * Kick the re-probe thread. It may already be scheduled, but it is | |
193 | * safe to kick it again. | |
194 | */ | |
e611f8cd | 195 | queue_work(system_unbound_wq, &deferred_probe_work); |
d1c3414c GL |
196 | } |
197 | ||
013c074f | 198 | /** |
dbf03d65 | 199 | * device_block_probing() - Block/defer device's probes |
013c074f SG |
200 | * |
201 | * It will disable probing of devices and defer their probes instead. | |
202 | */ | |
203 | void device_block_probing(void) | |
204 | { | |
205 | defer_all_probes = true; | |
206 | /* sync with probes to avoid races. */ | |
207 | wait_for_device_probe(); | |
208 | } | |
209 | ||
210 | /** | |
211 | * device_unblock_probing() - Unblock/enable device's probes | |
212 | * | |
213 | * It will restore normal behavior and trigger re-probing of deferred | |
214 | * devices. | |
215 | */ | |
216 | void device_unblock_probing(void) | |
217 | { | |
218 | defer_all_probes = false; | |
219 | driver_deferred_probe_trigger(); | |
220 | } | |
221 | ||
d090b70e AH |
222 | /** |
223 | * device_set_deferred_probe_reason() - Set defer probe reason message for device | |
224 | * @dev: the pointer to the struct device | |
225 | * @vaf: the pointer to va_format structure with message | |
226 | */ | |
227 | void device_set_deferred_probe_reason(const struct device *dev, struct va_format *vaf) | |
228 | { | |
229 | const char *drv = dev_driver_string(dev); | |
72a91f19 | 230 | char *reason; |
d090b70e AH |
231 | |
232 | mutex_lock(&deferred_probe_mutex); | |
233 | ||
72a91f19 AF |
234 | reason = kasprintf(GFP_KERNEL, "%s: %pV", drv, vaf); |
235 | __device_set_deferred_probe_reason(dev, reason); | |
d090b70e AH |
236 | |
237 | mutex_unlock(&deferred_probe_mutex); | |
238 | } | |
239 | ||
28af109a JMC |
240 | /* |
241 | * deferred_devs_show() - Show the devices in the deferred probe pending list. | |
242 | */ | |
243 | static int deferred_devs_show(struct seq_file *s, void *data) | |
244 | { | |
245 | struct device_private *curr; | |
246 | ||
247 | mutex_lock(&deferred_probe_mutex); | |
248 | ||
249 | list_for_each_entry(curr, &deferred_probe_pending_list, deferred_probe) | |
d090b70e AH |
250 | seq_printf(s, "%s\t%s", dev_name(curr->device), |
251 | curr->device->p->deferred_probe_reason ?: "\n"); | |
28af109a JMC |
252 | |
253 | mutex_unlock(&deferred_probe_mutex); | |
254 | ||
255 | return 0; | |
256 | } | |
257 | DEFINE_SHOW_ATTRIBUTE(deferred_devs); | |
258 | ||
f516d01b | 259 | #ifdef CONFIG_MODULES |
504fa212 | 260 | static int driver_deferred_probe_timeout = 10; |
f516d01b | 261 | #else |
504fa212 | 262 | static int driver_deferred_probe_timeout; |
f516d01b SK |
263 | #endif |
264 | ||
25b4e70d RH |
265 | static int __init deferred_probe_timeout_setup(char *str) |
266 | { | |
63c98047 MS |
267 | int timeout; |
268 | ||
269 | if (!kstrtoint(str, 10, &timeout)) | |
64c775fb | 270 | driver_deferred_probe_timeout = timeout; |
25b4e70d RH |
271 | return 1; |
272 | } | |
273 | __setup("deferred_probe_timeout=", deferred_probe_timeout_setup); | |
274 | ||
13a8e0f6 SK |
275 | /** |
276 | * driver_deferred_probe_check_state() - Check deferred probe state | |
277 | * @dev: device to check | |
278 | * | |
279 | * Return: | |
280 | * * -ENODEV if initcalls have completed and modules are disabled. | |
281 | * * -ETIMEDOUT if the deferred probe timeout was set and has expired | |
282 | * and modules are enabled. | |
283 | * * -EPROBE_DEFER in other cases. | |
284 | * | |
285 | * Drivers or subsystems can opt-in to calling this function instead of directly | |
286 | * returning -EPROBE_DEFER. | |
287 | */ | |
288 | int driver_deferred_probe_check_state(struct device *dev) | |
289 | { | |
290 | if (!IS_ENABLED(CONFIG_MODULES) && initcalls_done) { | |
291 | dev_warn(dev, "ignoring dependency for device, assuming no driver\n"); | |
292 | return -ENODEV; | |
293 | } | |
294 | ||
295 | if (!driver_deferred_probe_timeout && initcalls_done) { | |
296 | dev_warn(dev, "deferred probe timeout, ignoring dependency\n"); | |
297 | return -ETIMEDOUT; | |
298 | } | |
299 | ||
300 | return -EPROBE_DEFER; | |
301 | } | |
302 | EXPORT_SYMBOL_GPL(driver_deferred_probe_check_state); | |
303 | ||
25b4e70d RH |
304 | static void deferred_probe_timeout_work_func(struct work_struct *work) |
305 | { | |
eed6e418 | 306 | struct device_private *p; |
25b4e70d | 307 | |
d46f3e3e SK |
308 | fw_devlink_drivers_done(); |
309 | ||
13a8e0f6 | 310 | driver_deferred_probe_timeout = 0; |
25b4e70d RH |
311 | driver_deferred_probe_trigger(); |
312 | flush_work(&deferred_probe_work); | |
313 | ||
eed6e418 SK |
314 | mutex_lock(&deferred_probe_mutex); |
315 | list_for_each_entry(p, &deferred_probe_pending_list, deferred_probe) | |
316 | dev_info(p->device, "deferred probe pending\n"); | |
317 | mutex_unlock(&deferred_probe_mutex); | |
25b4e70d RH |
318 | } |
319 | static DECLARE_DELAYED_WORK(deferred_probe_timeout_work, deferred_probe_timeout_work_func); | |
320 | ||
2b28a1a8 SK |
321 | void deferred_probe_extend_timeout(void) |
322 | { | |
323 | /* | |
324 | * If the work hasn't been queued yet or if the work expired, don't | |
325 | * start a new one. | |
326 | */ | |
327 | if (cancel_delayed_work(&deferred_probe_timeout_work)) { | |
328 | schedule_delayed_work(&deferred_probe_timeout_work, | |
329 | driver_deferred_probe_timeout * HZ); | |
330 | pr_debug("Extended deferred probe timeout by %d secs\n", | |
331 | driver_deferred_probe_timeout); | |
332 | } | |
333 | } | |
334 | ||
d1c3414c GL |
335 | /** |
336 | * deferred_probe_initcall() - Enable probing of deferred devices | |
337 | * | |
338 | * We don't want to get in the way when the bulk of drivers are getting probed. | |
339 | * Instead, this initcall makes sure that deferred probing is delayed until | |
340 | * late_initcall time. | |
341 | */ | |
342 | static int deferred_probe_initcall(void) | |
343 | { | |
2942df67 GKH |
344 | debugfs_create_file("devices_deferred", 0444, NULL, NULL, |
345 | &deferred_devs_fops); | |
28af109a | 346 | |
d1c3414c GL |
347 | driver_deferred_probe_enable = true; |
348 | driver_deferred_probe_trigger(); | |
d72cca1e | 349 | /* Sort as many dependencies as possible before exiting initcalls */ |
2c507e46 | 350 | flush_work(&deferred_probe_work); |
25b4e70d RH |
351 | initcalls_done = true; |
352 | ||
d46f3e3e SK |
353 | if (!IS_ENABLED(CONFIG_MODULES)) |
354 | fw_devlink_drivers_done(); | |
355 | ||
25b4e70d RH |
356 | /* |
357 | * Trigger deferred probe again, this time we won't defer anything | |
358 | * that is optional | |
359 | */ | |
360 | driver_deferred_probe_trigger(); | |
361 | flush_work(&deferred_probe_work); | |
362 | ||
64c775fb | 363 | if (driver_deferred_probe_timeout > 0) { |
25b4e70d | 364 | schedule_delayed_work(&deferred_probe_timeout_work, |
64c775fb | 365 | driver_deferred_probe_timeout * HZ); |
25b4e70d | 366 | } |
d1c3414c GL |
367 | return 0; |
368 | } | |
369 | late_initcall(deferred_probe_initcall); | |
07e4a3e2 | 370 | |
28af109a JMC |
371 | static void __exit deferred_probe_exit(void) |
372 | { | |
36c893d3 | 373 | debugfs_lookup_and_remove("devices_deferred", NULL); |
28af109a JMC |
374 | } |
375 | __exitcall(deferred_probe_exit); | |
376 | ||
6b9cb427 TV |
377 | /** |
378 | * device_is_bound() - Check if device is bound to a driver | |
379 | * @dev: device to check | |
380 | * | |
381 | * Returns true if passed device has already finished probing successfully | |
382 | * against a driver. | |
383 | * | |
384 | * This function must be called with the device lock held. | |
385 | */ | |
386 | bool device_is_bound(struct device *dev) | |
387 | { | |
3ded9104 | 388 | return dev->p && klist_node_attached(&dev->p->knode_driver); |
6b9cb427 TV |
389 | } |
390 | ||
1901fb26 | 391 | static void driver_bound(struct device *dev) |
07e4a3e2 | 392 | { |
6b9cb427 | 393 | if (device_is_bound(dev)) { |
eb7fbc9f | 394 | pr_warn("%s: device %s already bound\n", |
2b3a302a | 395 | __func__, kobject_name(&dev->kobj)); |
1901fb26 | 396 | return; |
f86db396 | 397 | } |
4c898c7f | 398 | |
94f8cc0e FR |
399 | pr_debug("driver: '%s': %s: bound to device '%s'\n", dev->driver->name, |
400 | __func__, dev_name(dev)); | |
116af378 | 401 | |
fbb88fad | 402 | klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices); |
9ed98953 | 403 | device_links_driver_bound(dev); |
fbb88fad | 404 | |
aa8e54b5 TV |
405 | device_pm_check_callbacks(dev); |
406 | ||
8b0372a2 GKH |
407 | /* |
408 | * Make sure the device is no longer in one of the deferred lists and | |
409 | * kick off retrying all pending devices | |
410 | */ | |
d1c3414c GL |
411 | driver_deferred_probe_del(dev); |
412 | driver_deferred_probe_trigger(); | |
413 | ||
ed9f9181 | 414 | bus_notify(dev, BUS_NOTIFY_BOUND_DRIVER); |
1455cf8d | 415 | kobject_uevent(&dev->kobj, KOBJ_BIND); |
1901fb26 KS |
416 | } |
417 | ||
3c47d19f AS |
418 | static ssize_t coredump_store(struct device *dev, struct device_attribute *attr, |
419 | const char *buf, size_t count) | |
420 | { | |
421 | device_lock(dev); | |
1fe56e0c | 422 | dev->driver->coredump(dev); |
3c47d19f AS |
423 | device_unlock(dev); |
424 | ||
425 | return count; | |
426 | } | |
427 | static DEVICE_ATTR_WO(coredump); | |
428 | ||
1901fb26 KS |
429 | static int driver_sysfs_add(struct device *dev) |
430 | { | |
431 | int ret; | |
432 | ||
ed9f9181 | 433 | bus_notify(dev, BUS_NOTIFY_BIND_DRIVER); |
45daef0f | 434 | |
e5dd1278 | 435 | ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj, |
3c47d19f AS |
436 | kobject_name(&dev->kobj)); |
437 | if (ret) | |
438 | goto fail; | |
439 | ||
440 | ret = sysfs_create_link(&dev->kobj, &dev->driver->p->kobj, | |
441 | "driver"); | |
442 | if (ret) | |
443 | goto rm_dev; | |
444 | ||
d225ef6f JJB |
445 | if (!IS_ENABLED(CONFIG_DEV_COREDUMP) || !dev->driver->coredump) |
446 | return 0; | |
447 | ||
448 | ret = device_create_file(dev, &dev_attr_coredump); | |
449 | if (!ret) | |
3c47d19f AS |
450 | return 0; |
451 | ||
452 | sysfs_remove_link(&dev->kobj, "driver"); | |
453 | ||
454 | rm_dev: | |
455 | sysfs_remove_link(&dev->driver->p->kobj, | |
07e4a3e2 | 456 | kobject_name(&dev->kobj)); |
3c47d19f AS |
457 | |
458 | fail: | |
f86db396 | 459 | return ret; |
07e4a3e2 | 460 | } |
461 | ||
1901fb26 KS |
462 | static void driver_sysfs_remove(struct device *dev) |
463 | { | |
464 | struct device_driver *drv = dev->driver; | |
465 | ||
466 | if (drv) { | |
3c47d19f AS |
467 | if (drv->coredump) |
468 | device_remove_file(dev, &dev_attr_coredump); | |
e5dd1278 | 469 | sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj)); |
1901fb26 KS |
470 | sysfs_remove_link(&dev->kobj, "driver"); |
471 | } | |
472 | } | |
473 | ||
474 | /** | |
4a3ad20c GKH |
475 | * device_bind_driver - bind a driver to one device. |
476 | * @dev: device. | |
1901fb26 | 477 | * |
4a3ad20c GKH |
478 | * Allow manual attachment of a driver to a device. |
479 | * Caller must have already set @dev->driver. | |
1901fb26 | 480 | * |
fe940d73 LW |
481 | * Note that this does not modify the bus reference count. |
482 | * Please verify that is accounted for before calling this. | |
483 | * (It is ok to call with no other effort from a driver's probe() method.) | |
1901fb26 | 484 | * |
8e9394ce | 485 | * This function must be called with the device lock held. |
0d9f837c JG |
486 | * |
487 | * Callers should prefer to use device_driver_attach() instead. | |
1901fb26 KS |
488 | */ |
489 | int device_bind_driver(struct device *dev) | |
490 | { | |
cb986b74 CH |
491 | int ret; |
492 | ||
493 | ret = driver_sysfs_add(dev); | |
b6f617df SK |
494 | if (!ret) { |
495 | device_links_force_bind(dev); | |
cb986b74 | 496 | driver_bound(dev); |
b6f617df | 497 | } |
ed9f9181 GKH |
498 | else |
499 | bus_notify(dev, BUS_NOTIFY_DRIVER_NOT_BOUND); | |
cb986b74 | 500 | return ret; |
1901fb26 | 501 | } |
4a3ad20c | 502 | EXPORT_SYMBOL_GPL(device_bind_driver); |
1901fb26 | 503 | |
d779249e | 504 | static atomic_t probe_count = ATOMIC_INIT(0); |
735a7ffb AM |
505 | static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue); |
506 | ||
8fd456ec SK |
507 | static ssize_t state_synced_show(struct device *dev, |
508 | struct device_attribute *attr, char *buf) | |
509 | { | |
510 | bool val; | |
511 | ||
512 | device_lock(dev); | |
513 | val = dev->state_synced; | |
514 | device_unlock(dev); | |
948b3edb | 515 | |
aa838896 | 516 | return sysfs_emit(buf, "%u\n", val); |
8fd456ec SK |
517 | } |
518 | static DEVICE_ATTR_RO(state_synced); | |
519 | ||
9ad30721 RH |
520 | static void device_unbind_cleanup(struct device *dev) |
521 | { | |
522 | devres_release_all(dev); | |
523 | arch_teardown_dma_ops(dev); | |
524 | kfree(dev->dma_range_map); | |
525 | dev->dma_range_map = NULL; | |
526 | dev->driver = NULL; | |
527 | dev_set_drvdata(dev, NULL); | |
528 | if (dev->pm_domain && dev->pm_domain->dismiss) | |
529 | dev->pm_domain->dismiss(dev); | |
530 | pm_runtime_reinit(dev); | |
531 | dev_pm_set_driver_flags(dev, 0); | |
532 | } | |
e1499647 | 533 | |
4b775aaf RH |
534 | static void device_remove(struct device *dev) |
535 | { | |
536 | device_remove_file(dev, &dev_attr_state_synced); | |
537 | device_remove_groups(dev, dev->driver->dev_groups); | |
538 | ||
539 | if (dev->bus && dev->bus->remove) | |
540 | dev->bus->remove(dev); | |
541 | else if (dev->driver->remove) | |
542 | dev->driver->remove(dev); | |
543 | } | |
544 | ||
e1499647 CH |
545 | static int call_driver_probe(struct device *dev, struct device_driver *drv) |
546 | { | |
547 | int ret = 0; | |
548 | ||
549 | if (dev->bus->probe) | |
550 | ret = dev->bus->probe(dev); | |
551 | else if (drv->probe) | |
552 | ret = drv->probe(dev); | |
553 | ||
554 | switch (ret) { | |
555 | case 0: | |
556 | break; | |
557 | case -EPROBE_DEFER: | |
558 | /* Driver requested deferred probing */ | |
559 | dev_dbg(dev, "Driver %s requests probe deferral\n", drv->name); | |
560 | break; | |
561 | case -ENODEV: | |
562 | case -ENXIO: | |
563 | pr_debug("%s: probe of %s rejects match %d\n", | |
564 | drv->name, dev_name(dev), ret); | |
565 | break; | |
566 | default: | |
567 | /* driver matched but the probe failed */ | |
568 | pr_warn("%s: probe of %s failed with error %d\n", | |
569 | drv->name, dev_name(dev), ret); | |
570 | break; | |
571 | } | |
572 | ||
573 | return ret; | |
574 | } | |
575 | ||
21c7f30b | 576 | static int really_probe(struct device *dev, struct device_driver *drv) |
07e4a3e2 | 577 | { |
c5f06274 RH |
578 | bool test_remove = IS_ENABLED(CONFIG_DEBUG_TEST_DRIVER_REMOVE) && |
579 | !drv->suppress_bind_attrs; | |
2f8c3ae8 | 580 | int ret, link_ret; |
07e4a3e2 | 581 | |
013c074f SG |
582 | if (defer_all_probes) { |
583 | /* | |
584 | * Value of defer_all_probes can be set only by | |
dbf03d65 | 585 | * device_block_probing() which, in turn, will call |
013c074f SG |
586 | * wait_for_device_probe() right after that to avoid any races. |
587 | */ | |
588 | dev_dbg(dev, "Driver %s force probe deferral\n", drv->name); | |
45ddcb42 | 589 | return -EPROBE_DEFER; |
013c074f SG |
590 | } |
591 | ||
2f8c3ae8 SK |
592 | link_ret = device_links_check_suppliers(dev); |
593 | if (link_ret == -EPROBE_DEFER) | |
594 | return link_ret; | |
9ed98953 | 595 | |
7dc72b28 | 596 | pr_debug("bus: '%s': %s: probing driver %s with device %s\n", |
1e0b2cf9 | 597 | drv->bus->name, __func__, drv->name, dev_name(dev)); |
7c35e699 GU |
598 | if (!list_empty(&dev->devres_head)) { |
599 | dev_crit(dev, "Resources present before probing\n"); | |
b292b50b TH |
600 | ret = -EBUSY; |
601 | goto done; | |
7c35e699 | 602 | } |
07e4a3e2 | 603 | |
bea5b158 | 604 | re_probe: |
07e4a3e2 | 605 | dev->driver = drv; |
ab78029e LW |
606 | |
607 | /* If using pinctrl, bind pins now before probing */ | |
608 | ret = pinctrl_bind_pins(dev); | |
609 | if (ret) | |
14b6257a | 610 | goto pinctrl_bind_failed; |
ab78029e | 611 | |
ccf640f4 CH |
612 | if (dev->bus->dma_configure) { |
613 | ret = dev->bus->dma_configure(dev); | |
614 | if (ret) | |
00eb74ea | 615 | goto pinctrl_bind_failed; |
ccf640f4 | 616 | } |
09515ef5 | 617 | |
f04948de ZL |
618 | ret = driver_sysfs_add(dev); |
619 | if (ret) { | |
eb7fbc9f CJ |
620 | pr_err("%s: driver_sysfs_add(%s) failed\n", |
621 | __func__, dev_name(dev)); | |
885e5025 | 622 | goto sysfs_failed; |
1901fb26 KS |
623 | } |
624 | ||
e90d5532 RW |
625 | if (dev->pm_domain && dev->pm_domain->activate) { |
626 | ret = dev->pm_domain->activate(dev); | |
627 | if (ret) | |
628 | goto probe_failed; | |
629 | } | |
630 | ||
45ddcb42 CH |
631 | ret = call_driver_probe(dev, drv); |
632 | if (ret) { | |
2f8c3ae8 SK |
633 | /* |
634 | * If fw_devlink_best_effort is active (denoted by -EAGAIN), the | |
635 | * device might actually probe properly once some of its missing | |
636 | * suppliers have probed. So, treat this as if the driver | |
637 | * returned -EPROBE_DEFER. | |
638 | */ | |
639 | if (link_ret == -EAGAIN) | |
640 | ret = -EPROBE_DEFER; | |
641 | ||
e1499647 | 642 | /* |
ef6dcbdd CH |
643 | * Return probe errors as positive values so that the callers |
644 | * can distinguish them from other errors. | |
e1499647 | 645 | */ |
45ddcb42 | 646 | ret = -ret; |
e1499647 | 647 | goto probe_failed; |
f86db396 | 648 | } |
1901fb26 | 649 | |
f04948de ZL |
650 | ret = device_add_groups(dev, drv->dev_groups); |
651 | if (ret) { | |
23b69044 DT |
652 | dev_err(dev, "device_add_groups() failed\n"); |
653 | goto dev_groups_failed; | |
654 | } | |
655 | ||
f04948de ZL |
656 | if (dev_has_sync_state(dev)) { |
657 | ret = device_create_file(dev, &dev_attr_state_synced); | |
658 | if (ret) { | |
659 | dev_err(dev, "state_synced sysfs add failed\n"); | |
660 | goto dev_sysfs_state_synced_failed; | |
661 | } | |
8fd456ec SK |
662 | } |
663 | ||
bea5b158 RH |
664 | if (test_remove) { |
665 | test_remove = false; | |
666 | ||
4b775aaf | 667 | device_remove(dev); |
bea5b158 | 668 | driver_sysfs_remove(dev); |
9ad30721 | 669 | device_unbind_cleanup(dev); |
bea5b158 RH |
670 | |
671 | goto re_probe; | |
672 | } | |
673 | ||
ef0eebc0 DA |
674 | pinctrl_init_done(dev); |
675 | ||
e90d5532 RW |
676 | if (dev->pm_domain && dev->pm_domain->sync) |
677 | dev->pm_domain->sync(dev); | |
678 | ||
1901fb26 | 679 | driver_bound(dev); |
7dc72b28 | 680 | pr_debug("bus: '%s': %s: bound device %s to driver %s\n", |
1e0b2cf9 | 681 | drv->bus->name, __func__, dev_name(dev), drv->name); |
d779249e | 682 | goto done; |
0d3e5a2e | 683 | |
8fd456ec | 684 | dev_sysfs_state_synced_failed: |
23b69044 | 685 | dev_groups_failed: |
4b775aaf | 686 | device_remove(dev); |
d779249e | 687 | probe_failed: |
885e5025 LB |
688 | driver_sysfs_remove(dev); |
689 | sysfs_failed: | |
ed9f9181 | 690 | bus_notify(dev, BUS_NOTIFY_DRIVER_NOT_BOUND); |
25f3bcfc LB |
691 | if (dev->bus && dev->bus->dma_cleanup) |
692 | dev->bus->dma_cleanup(dev); | |
14b6257a | 693 | pinctrl_bind_failed: |
9ed98953 | 694 | device_links_no_driver(dev); |
9ad30721 | 695 | device_unbind_cleanup(dev); |
d779249e | 696 | done: |
d779249e GKH |
697 | return ret; |
698 | } | |
699 | ||
0a50f61c TP |
700 | /* |
701 | * For initcall_debug, show the driver probe time. | |
702 | */ | |
703 | static int really_probe_debug(struct device *dev, struct device_driver *drv) | |
704 | { | |
e3aa745f | 705 | ktime_t calltime, rettime; |
0a50f61c TP |
706 | int ret; |
707 | ||
708 | calltime = ktime_get(); | |
709 | ret = really_probe(dev, drv); | |
710 | rettime = ktime_get(); | |
eb7fbc9f | 711 | pr_debug("probe of %s returned %d after %lld usecs\n", |
e3aa745f | 712 | dev_name(dev), ret, ktime_us_delta(rettime, calltime)); |
0a50f61c TP |
713 | return ret; |
714 | } | |
715 | ||
d779249e GKH |
716 | /** |
717 | * driver_probe_done | |
718 | * Determine if the probe sequence is finished or not. | |
719 | * | |
720 | * Should somehow figure out how to use a semaphore, not an atomic variable... | |
721 | */ | |
722 | int driver_probe_done(void) | |
723 | { | |
927f8287 AS |
724 | int local_probe_count = atomic_read(&probe_count); |
725 | ||
726 | pr_debug("%s: probe_count = %d\n", __func__, local_probe_count); | |
727 | if (local_probe_count) | |
d779249e GKH |
728 | return -EBUSY; |
729 | return 0; | |
730 | } | |
731 | ||
216773a7 AV |
732 | /** |
733 | * wait_for_device_probe | |
734 | * Wait for device probing to be completed. | |
216773a7 | 735 | */ |
b23530eb | 736 | void wait_for_device_probe(void) |
216773a7 | 737 | { |
013c074f | 738 | /* wait for the deferred probe workqueue to finish */ |
2c507e46 | 739 | flush_work(&deferred_probe_work); |
013c074f | 740 | |
216773a7 | 741 | /* wait for the known devices to complete their probing */ |
b23530eb | 742 | wait_event(probe_waitqueue, atomic_read(&probe_count) == 0); |
216773a7 | 743 | async_synchronize_full(); |
216773a7 | 744 | } |
d4d5291c | 745 | EXPORT_SYMBOL_GPL(wait_for_device_probe); |
216773a7 | 746 | |
45ddcb42 | 747 | static int __driver_probe_device(struct device_driver *drv, struct device *dev) |
d779249e | 748 | { |
d779249e GKH |
749 | int ret = 0; |
750 | ||
204db60c | 751 | if (dev->p->dead || !device_is_registered(dev)) |
f2eaae19 | 752 | return -ENODEV; |
204db60c JG |
753 | if (dev->driver) |
754 | return -EBUSY; | |
d779249e | 755 | |
f2db85b6 | 756 | dev->can_match = true; |
7dc72b28 | 757 | pr_debug("bus: '%s': %s: matched device %s with driver %s\n", |
1e0b2cf9 | 758 | drv->bus->name, __func__, dev_name(dev), drv->name); |
d779249e | 759 | |
b06c0b2f | 760 | pm_runtime_get_suppliers(dev); |
ddef08dd RW |
761 | if (dev->parent) |
762 | pm_runtime_get_sync(dev->parent); | |
763 | ||
5e928f77 | 764 | pm_runtime_barrier(dev); |
0a50f61c TP |
765 | if (initcall_debug) |
766 | ret = really_probe_debug(dev, drv); | |
767 | else | |
768 | ret = really_probe(dev, drv); | |
fa180eb4 | 769 | pm_request_idle(dev); |
d779249e | 770 | |
ddef08dd RW |
771 | if (dev->parent) |
772 | pm_runtime_put(dev->parent); | |
773 | ||
b06c0b2f | 774 | pm_runtime_put_suppliers(dev); |
0d3e5a2e | 775 | return ret; |
07e4a3e2 | 776 | } |
777 | ||
45ddcb42 CH |
778 | /** |
779 | * driver_probe_device - attempt to bind device & driver together | |
780 | * @drv: driver to bind a device to | |
781 | * @dev: device to try to bind to the driver | |
782 | * | |
783 | * This function returns -ENODEV if the device is not registered, -EBUSY if it | |
784 | * already has a driver, 0 if the device is bound successfully and a positive | |
785 | * (inverted) error code for failures from the ->probe method. | |
786 | * | |
787 | * This function must be called with @dev lock held. When called for a | |
788 | * USB interface, @dev->parent lock must be held as well. | |
789 | * | |
790 | * If the device has a parent, runtime-resume the parent before driver probing. | |
791 | */ | |
792 | static int driver_probe_device(struct device_driver *drv, struct device *dev) | |
793 | { | |
794 | int trigger_count = atomic_read(&deferred_trigger_count); | |
795 | int ret; | |
796 | ||
797 | atomic_inc(&probe_count); | |
798 | ret = __driver_probe_device(drv, dev); | |
799 | if (ret == -EPROBE_DEFER || ret == EPROBE_DEFER) { | |
800 | driver_deferred_probe_add(dev); | |
801 | ||
802 | /* | |
803 | * Did a trigger occur while probing? Need to re-trigger if yes | |
804 | */ | |
805 | if (trigger_count != atomic_read(&deferred_trigger_count) && | |
806 | !defer_all_probes) | |
807 | driver_deferred_probe_trigger(); | |
808 | } | |
809 | atomic_dec(&probe_count); | |
810 | wake_up_all(&probe_waitqueue); | |
811 | return ret; | |
812 | } | |
813 | ||
1ea61b68 FT |
814 | static inline bool cmdline_requested_async_probing(const char *drv_name) |
815 | { | |
f79f662e SK |
816 | bool async_drv; |
817 | ||
818 | async_drv = parse_option_str(async_probe_drv_names, drv_name); | |
819 | ||
820 | return (async_probe_default != async_drv); | |
1ea61b68 FT |
821 | } |
822 | ||
823 | /* The option format is "driver_async_probe=drv_name1,drv_name2,..." */ | |
824 | static int __init save_async_options(char *buf) | |
825 | { | |
826 | if (strlen(buf) >= ASYNC_DRV_NAMES_MAX_LEN) | |
eb7fbc9f | 827 | pr_warn("Too long list of driver names for 'driver_async_probe'!\n"); |
1ea61b68 | 828 | |
07b7b883 | 829 | strscpy(async_probe_drv_names, buf, ASYNC_DRV_NAMES_MAX_LEN); |
f79f662e SK |
830 | async_probe_default = parse_option_str(async_probe_drv_names, "*"); |
831 | ||
f2aad547 | 832 | return 1; |
1ea61b68 FT |
833 | } |
834 | __setup("driver_async_probe=", save_async_options); | |
835 | ||
189a87f8 | 836 | static bool driver_allows_async_probing(struct device_driver *drv) |
2287c322 | 837 | { |
d173a137 LR |
838 | switch (drv->probe_type) { |
839 | case PROBE_PREFER_ASYNCHRONOUS: | |
f2411da7 LR |
840 | return true; |
841 | ||
d173a137 LR |
842 | case PROBE_FORCE_SYNCHRONOUS: |
843 | return false; | |
844 | ||
845 | default: | |
1ea61b68 FT |
846 | if (cmdline_requested_async_probing(drv->name)) |
847 | return true; | |
848 | ||
80c6e146 | 849 | if (module_requested_async_probing(drv->owner)) |
d173a137 | 850 | return true; |
f2411da7 | 851 | |
d173a137 LR |
852 | return false; |
853 | } | |
765230b5 DT |
854 | } |
855 | ||
856 | struct device_attach_data { | |
857 | struct device *dev; | |
858 | ||
859 | /* | |
b4ae8c2f | 860 | * Indicates whether we are considering asynchronous probing or |
765230b5 DT |
861 | * not. Only initial binding after device or driver registration |
862 | * (including deferral processing) may be done asynchronously, the | |
863 | * rest is always synchronous, as we expect it is being done by | |
864 | * request from userspace. | |
865 | */ | |
866 | bool check_async; | |
867 | ||
868 | /* | |
869 | * Indicates if we are binding synchronous or asynchronous drivers. | |
870 | * When asynchronous probing is enabled we'll execute 2 passes | |
871 | * over drivers: first pass doing synchronous probing and second | |
872 | * doing asynchronous probing (if synchronous did not succeed - | |
873 | * most likely because there was no driver requiring synchronous | |
874 | * probing - and we found asynchronous driver during first pass). | |
875 | * The 2 passes are done because we can't shoot asynchronous | |
876 | * probe for given device and driver from bus_for_each_drv() since | |
877 | * driver pointer is not guaranteed to stay valid once | |
878 | * bus_for_each_drv() iterates to the next driver on the bus. | |
879 | */ | |
880 | bool want_async; | |
881 | ||
882 | /* | |
883 | * We'll set have_async to 'true' if, while scanning for matching | |
884 | * driver, we'll encounter one that requests asynchronous probing. | |
885 | */ | |
886 | bool have_async; | |
887 | }; | |
888 | ||
889 | static int __device_attach_driver(struct device_driver *drv, void *_data) | |
890 | { | |
891 | struct device_attach_data *data = _data; | |
892 | struct device *dev = data->dev; | |
893 | bool async_allowed; | |
656b8035 | 894 | int ret; |
765230b5 | 895 | |
656b8035 TV |
896 | ret = driver_match_device(drv, dev); |
897 | if (ret == 0) { | |
898 | /* no match */ | |
49b420a1 | 899 | return 0; |
656b8035 TV |
900 | } else if (ret == -EPROBE_DEFER) { |
901 | dev_dbg(dev, "Device match requests probe deferral\n"); | |
f2db85b6 | 902 | dev->can_match = true; |
656b8035 | 903 | driver_deferred_probe_add(dev); |
25e9fbf0 IM |
904 | /* |
905 | * Device can't match with a driver right now, so don't attempt | |
906 | * to match or bind with other drivers on the bus. | |
907 | */ | |
908 | return ret; | |
656b8035 | 909 | } else if (ret < 0) { |
eb7fbc9f | 910 | dev_dbg(dev, "Bus failed to match device: %d\n", ret); |
656b8035 TV |
911 | return ret; |
912 | } /* ret > 0 means positive match */ | |
49b420a1 | 913 | |
765230b5 DT |
914 | async_allowed = driver_allows_async_probing(drv); |
915 | ||
916 | if (async_allowed) | |
917 | data->have_async = true; | |
918 | ||
919 | if (data->check_async && async_allowed != data->want_async) | |
920 | return 0; | |
921 | ||
ef6dcbdd CH |
922 | /* |
923 | * Ignore errors returned by ->probe so that the next driver can try | |
924 | * its luck. | |
925 | */ | |
926 | ret = driver_probe_device(drv, dev); | |
927 | if (ret < 0) | |
928 | return ret; | |
929 | return ret == 0; | |
2287c322 | 930 | } |
931 | ||
765230b5 DT |
932 | static void __device_attach_async_helper(void *_dev, async_cookie_t cookie) |
933 | { | |
934 | struct device *dev = _dev; | |
935 | struct device_attach_data data = { | |
936 | .dev = dev, | |
937 | .check_async = true, | |
938 | .want_async = true, | |
939 | }; | |
940 | ||
941 | device_lock(dev); | |
942 | ||
3451a495 AD |
943 | /* |
944 | * Check if device has already been removed or claimed. This may | |
945 | * happen with driver loading, device discovery/registration, | |
946 | * and deferred probe processing happens all at once with | |
947 | * multiple threads. | |
948 | */ | |
949 | if (dev->p->dead || dev->driver) | |
950 | goto out_unlock; | |
951 | ||
ddef08dd RW |
952 | if (dev->parent) |
953 | pm_runtime_get_sync(dev->parent); | |
954 | ||
765230b5 DT |
955 | bus_for_each_drv(dev->bus, NULL, &data, __device_attach_driver); |
956 | dev_dbg(dev, "async probe completed\n"); | |
957 | ||
958 | pm_request_idle(dev); | |
959 | ||
ddef08dd RW |
960 | if (dev->parent) |
961 | pm_runtime_put(dev->parent); | |
3451a495 | 962 | out_unlock: |
765230b5 DT |
963 | device_unlock(dev); |
964 | ||
965 | put_device(dev); | |
966 | } | |
967 | ||
802a87fd | 968 | static int __device_attach(struct device *dev, bool allow_async) |
07e4a3e2 | 969 | { |
0d3e5a2e | 970 | int ret = 0; |
b232b02b | 971 | bool async = false; |
0d3e5a2e | 972 | |
8e9394ce | 973 | device_lock(dev); |
65488832 LW |
974 | if (dev->p->dead) { |
975 | goto out_unlock; | |
976 | } else if (dev->driver) { | |
6b9cb427 | 977 | if (device_is_bound(dev)) { |
8497d6a2 SO |
978 | ret = 1; |
979 | goto out_unlock; | |
980 | } | |
f86db396 AM |
981 | ret = device_bind_driver(dev); |
982 | if (ret == 0) | |
983 | ret = 1; | |
c6a46696 CH |
984 | else { |
985 | dev->driver = NULL; | |
986 | ret = 0; | |
987 | } | |
21c7f30b | 988 | } else { |
765230b5 DT |
989 | struct device_attach_data data = { |
990 | .dev = dev, | |
991 | .check_async = allow_async, | |
992 | .want_async = false, | |
993 | }; | |
994 | ||
ddef08dd RW |
995 | if (dev->parent) |
996 | pm_runtime_get_sync(dev->parent); | |
997 | ||
765230b5 DT |
998 | ret = bus_for_each_drv(dev->bus, NULL, &data, |
999 | __device_attach_driver); | |
1000 | if (!ret && allow_async && data.have_async) { | |
1001 | /* | |
1002 | * If we could not find appropriate driver | |
1003 | * synchronously and we are allowed to do | |
1004 | * async probes and there are drivers that | |
1005 | * want to probe asynchronously, we'll | |
1006 | * try them. | |
1007 | */ | |
1008 | dev_dbg(dev, "scheduling asynchronous probe\n"); | |
1009 | get_device(dev); | |
b232b02b | 1010 | async = true; |
765230b5 DT |
1011 | } else { |
1012 | pm_request_idle(dev); | |
1013 | } | |
ddef08dd RW |
1014 | |
1015 | if (dev->parent) | |
1016 | pm_runtime_put(dev->parent); | |
21c7f30b | 1017 | } |
8497d6a2 | 1018 | out_unlock: |
8e9394ce | 1019 | device_unlock(dev); |
b232b02b ZW |
1020 | if (async) |
1021 | async_schedule_dev(__device_attach_async_helper, dev); | |
0d3e5a2e | 1022 | return ret; |
2287c322 | 1023 | } |
765230b5 DT |
1024 | |
1025 | /** | |
1026 | * device_attach - try to attach device to a driver. | |
1027 | * @dev: device. | |
1028 | * | |
1029 | * Walk the list of drivers that the bus has and call | |
1030 | * driver_probe_device() for each pair. If a compatible | |
1031 | * pair is found, break out and return. | |
1032 | * | |
1033 | * Returns 1 if the device was bound to a driver; | |
1034 | * 0 if no matching driver was found; | |
1035 | * -ENODEV if the device is not registered. | |
1036 | * | |
1037 | * When called for a USB interface, @dev->parent lock must be held. | |
1038 | */ | |
1039 | int device_attach(struct device *dev) | |
1040 | { | |
1041 | return __device_attach(dev, false); | |
1042 | } | |
4a3ad20c | 1043 | EXPORT_SYMBOL_GPL(device_attach); |
2287c322 | 1044 | |
765230b5 DT |
1045 | void device_initial_probe(struct device *dev) |
1046 | { | |
1047 | __device_attach(dev, true); | |
1048 | } | |
1049 | ||
ed88747c AD |
1050 | /* |
1051 | * __device_driver_lock - acquire locks needed to manipulate dev->drv | |
1052 | * @dev: Device we will update driver info for | |
1053 | * @parent: Parent device. Needed if the bus requires parent lock | |
1054 | * | |
1055 | * This function will take the required locks for manipulating dev->drv. | |
1056 | * Normally this will just be the @dev lock, but when called for a USB | |
1057 | * interface, @parent lock will be held as well. | |
1058 | */ | |
1059 | static void __device_driver_lock(struct device *dev, struct device *parent) | |
1060 | { | |
1061 | if (parent && dev->bus->need_parent_lock) | |
1062 | device_lock(parent); | |
1063 | device_lock(dev); | |
1064 | } | |
1065 | ||
1066 | /* | |
1067 | * __device_driver_unlock - release locks needed to manipulate dev->drv | |
1068 | * @dev: Device we will update driver info for | |
1069 | * @parent: Parent device. Needed if the bus requires parent lock | |
1070 | * | |
1071 | * This function will release the required locks for manipulating dev->drv. | |
b4ae8c2f | 1072 | * Normally this will just be the @dev lock, but when called for a |
ed88747c AD |
1073 | * USB interface, @parent lock will be released as well. |
1074 | */ | |
1075 | static void __device_driver_unlock(struct device *dev, struct device *parent) | |
1076 | { | |
1077 | device_unlock(dev); | |
1078 | if (parent && dev->bus->need_parent_lock) | |
1079 | device_unlock(parent); | |
1080 | } | |
1081 | ||
1082 | /** | |
1083 | * device_driver_attach - attach a specific driver to a specific device | |
1084 | * @drv: Driver to attach | |
1085 | * @dev: Device to attach it to | |
1086 | * | |
1087 | * Manually attach driver to a device. Will acquire both @dev lock and | |
ef6dcbdd | 1088 | * @dev->parent lock if needed. Returns 0 on success, -ERR on failure. |
ed88747c AD |
1089 | */ |
1090 | int device_driver_attach(struct device_driver *drv, struct device *dev) | |
1091 | { | |
204db60c | 1092 | int ret; |
ed88747c AD |
1093 | |
1094 | __device_driver_lock(dev, dev->parent); | |
45ddcb42 | 1095 | ret = __driver_probe_device(drv, dev); |
ed88747c AD |
1096 | __device_driver_unlock(dev, dev->parent); |
1097 | ||
ef6dcbdd CH |
1098 | /* also return probe errors as normal negative errnos */ |
1099 | if (ret > 0) | |
1100 | ret = -ret; | |
45ddcb42 CH |
1101 | if (ret == -EPROBE_DEFER) |
1102 | return -EAGAIN; | |
ed88747c AD |
1103 | return ret; |
1104 | } | |
0d9f837c | 1105 | EXPORT_SYMBOL_GPL(device_driver_attach); |
ed88747c | 1106 | |
ef0ff683 AD |
1107 | static void __driver_attach_async_helper(void *_dev, async_cookie_t cookie) |
1108 | { | |
1109 | struct device *dev = _dev; | |
1110 | struct device_driver *drv; | |
204db60c | 1111 | int ret; |
ef0ff683 AD |
1112 | |
1113 | __device_driver_lock(dev, dev->parent); | |
ef0ff683 | 1114 | drv = dev->p->async_driver; |
84e7c678 | 1115 | dev->p->async_driver = NULL; |
204db60c | 1116 | ret = driver_probe_device(drv, dev); |
ef0ff683 AD |
1117 | __device_driver_unlock(dev, dev->parent); |
1118 | ||
1119 | dev_dbg(dev, "driver %s async attach completed: %d\n", drv->name, ret); | |
1120 | ||
1121 | put_device(dev); | |
1122 | } | |
1123 | ||
4a3ad20c | 1124 | static int __driver_attach(struct device *dev, void *data) |
2287c322 | 1125 | { |
4a3ad20c | 1126 | struct device_driver *drv = data; |
70fe7583 | 1127 | bool async = false; |
656b8035 | 1128 | int ret; |
0d3e5a2e PM |
1129 | |
1130 | /* | |
1131 | * Lock device and try to bind to it. We drop the error | |
1132 | * here and always return 0, because we need to keep trying | |
1133 | * to bind to devices and some drivers will return an error | |
1134 | * simply if it didn't support the device. | |
1135 | * | |
1136 | * driver_probe_device() will spit a warning if there | |
1137 | * is an error. | |
1138 | */ | |
1139 | ||
656b8035 TV |
1140 | ret = driver_match_device(drv, dev); |
1141 | if (ret == 0) { | |
1142 | /* no match */ | |
6cd49586 | 1143 | return 0; |
656b8035 TV |
1144 | } else if (ret == -EPROBE_DEFER) { |
1145 | dev_dbg(dev, "Device match requests probe deferral\n"); | |
f2db85b6 | 1146 | dev->can_match = true; |
656b8035 | 1147 | driver_deferred_probe_add(dev); |
25e9fbf0 IM |
1148 | /* |
1149 | * Driver could not match with device, but may match with | |
1150 | * another device on the bus. | |
1151 | */ | |
1152 | return 0; | |
656b8035 | 1153 | } else if (ret < 0) { |
eb7fbc9f | 1154 | dev_dbg(dev, "Bus failed to match device: %d\n", ret); |
27c0d217 IM |
1155 | /* |
1156 | * Driver could not match with device, but may match with | |
1157 | * another device on the bus. | |
1158 | */ | |
1159 | return 0; | |
656b8035 | 1160 | } /* ret > 0 means positive match */ |
6cd49586 | 1161 | |
ef0ff683 AD |
1162 | if (driver_allows_async_probing(drv)) { |
1163 | /* | |
1164 | * Instead of probing the device synchronously we will | |
1165 | * probe it asynchronously to allow for more parallelism. | |
1166 | * | |
1167 | * We only take the device lock here in order to guarantee | |
1168 | * that the dev->driver and async_driver fields are protected | |
1169 | */ | |
1170 | dev_dbg(dev, "probing driver %s asynchronously\n", drv->name); | |
1171 | device_lock(dev); | |
84e7c678 | 1172 | if (!dev->driver && !dev->p->async_driver) { |
ef0ff683 AD |
1173 | get_device(dev); |
1174 | dev->p->async_driver = drv; | |
70fe7583 | 1175 | async = true; |
ef0ff683 AD |
1176 | } |
1177 | device_unlock(dev); | |
70fe7583 ZW |
1178 | if (async) |
1179 | async_schedule_dev(__driver_attach_async_helper, dev); | |
ef0ff683 AD |
1180 | return 0; |
1181 | } | |
1182 | ||
ef6dcbdd CH |
1183 | __device_driver_lock(dev, dev->parent); |
1184 | driver_probe_device(drv, dev); | |
1185 | __device_driver_unlock(dev, dev->parent); | |
0d3e5a2e | 1186 | |
07e4a3e2 | 1187 | return 0; |
1188 | } | |
1189 | ||
1190 | /** | |
4a3ad20c GKH |
1191 | * driver_attach - try to bind driver to devices. |
1192 | * @drv: driver. | |
07e4a3e2 | 1193 | * |
4a3ad20c GKH |
1194 | * Walk the list of devices that the bus has on it and try to |
1195 | * match the driver with each one. If driver_probe_device() | |
1196 | * returns 0 and the @dev->driver is set, we've found a | |
1197 | * compatible pair. | |
07e4a3e2 | 1198 | */ |
4a3ad20c | 1199 | int driver_attach(struct device_driver *drv) |
07e4a3e2 | 1200 | { |
f86db396 | 1201 | return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach); |
07e4a3e2 | 1202 | } |
4a3ad20c | 1203 | EXPORT_SYMBOL_GPL(driver_attach); |
07e4a3e2 | 1204 | |
ab71c6f0 | 1205 | /* |
8e9394ce GKH |
1206 | * __device_release_driver() must be called with @dev lock held. |
1207 | * When called for a USB interface, @dev->parent lock must be held as well. | |
07e4a3e2 | 1208 | */ |
9ed98953 | 1209 | static void __device_release_driver(struct device *dev, struct device *parent) |
07e4a3e2 | 1210 | { |
4a3ad20c | 1211 | struct device_driver *drv; |
07e4a3e2 | 1212 | |
ef2c5174 | 1213 | drv = dev->driver; |
c95a6b05 | 1214 | if (drv) { |
9226c504 RW |
1215 | pm_runtime_get_sync(dev); |
1216 | ||
9ed98953 | 1217 | while (device_links_busy(dev)) { |
ed88747c | 1218 | __device_driver_unlock(dev, parent); |
9ed98953 RW |
1219 | |
1220 | device_links_unbind_consumers(dev); | |
9ed98953 | 1221 | |
ed88747c | 1222 | __device_driver_lock(dev, parent); |
9ed98953 RW |
1223 | /* |
1224 | * A concurrent invocation of the same function might | |
1225 | * have released the driver successfully while this one | |
1226 | * was waiting, so check for that. | |
1227 | */ | |
9226c504 RW |
1228 | if (dev->driver != drv) { |
1229 | pm_runtime_put(dev); | |
9ed98953 | 1230 | return; |
9226c504 | 1231 | } |
9ed98953 RW |
1232 | } |
1233 | ||
1901fb26 | 1234 | driver_sysfs_remove(dev); |
0d3e5a2e | 1235 | |
ed9f9181 | 1236 | bus_notify(dev, BUS_NOTIFY_UNBIND_DRIVER); |
116af378 | 1237 | |
baab52de | 1238 | pm_runtime_put_sync(dev); |
e1866b33 | 1239 | |
4b775aaf | 1240 | device_remove(dev); |
9ed98953 | 1241 | |
25f3bcfc LB |
1242 | if (dev->bus && dev->bus->dma_cleanup) |
1243 | dev->bus->dma_cleanup(dev); | |
1244 | ||
9ed98953 | 1245 | device_links_driver_cleanup(dev); |
9ad30721 | 1246 | device_unbind_cleanup(dev); |
e90d5532 | 1247 | |
8940b4f3 | 1248 | klist_remove(&dev->p->knode_driver); |
aa8e54b5 | 1249 | device_pm_check_callbacks(dev); |
1455cf8d | 1250 | |
ed9f9181 | 1251 | bus_notify(dev, BUS_NOTIFY_UNBOUND_DRIVER); |
1455cf8d | 1252 | kobject_uevent(&dev->kobj, KOBJ_UNBIND); |
0d3e5a2e | 1253 | } |
07e4a3e2 | 1254 | } |
1255 | ||
9ed98953 RW |
1256 | void device_release_driver_internal(struct device *dev, |
1257 | struct device_driver *drv, | |
1258 | struct device *parent) | |
4bdb3550 | 1259 | { |
ed88747c | 1260 | __device_driver_lock(dev, parent); |
4bdb3550 | 1261 | |
4bdb3550 | 1262 | if (!drv || drv == dev->driver) |
9ed98953 | 1263 | __device_release_driver(dev, parent); |
4bdb3550 | 1264 | |
ed88747c | 1265 | __device_driver_unlock(dev, parent); |
4bdb3550 RW |
1266 | } |
1267 | ||
ab71c6f0 | 1268 | /** |
4a3ad20c GKH |
1269 | * device_release_driver - manually detach device from driver. |
1270 | * @dev: device. | |
ab71c6f0 | 1271 | * |
4a3ad20c | 1272 | * Manually detach device from driver. |
8e9394ce | 1273 | * When called for a USB interface, @dev->parent lock must be held. |
9ed98953 RW |
1274 | * |
1275 | * If this function is to be called with @dev->parent lock held, ensure that | |
1276 | * the device's consumers are unbound in advance or that their locks can be | |
1277 | * acquired under the @dev->parent lock. | |
ab71c6f0 | 1278 | */ |
4a3ad20c | 1279 | void device_release_driver(struct device *dev) |
94e7b1c5 | 1280 | { |
c95a6b05 AS |
1281 | /* |
1282 | * If anyone calls device_release_driver() recursively from | |
1283 | * within their ->remove callback for the same device, they | |
1284 | * will deadlock right here. | |
1285 | */ | |
4bdb3550 | 1286 | device_release_driver_internal(dev, NULL, NULL); |
94e7b1c5 | 1287 | } |
4a3ad20c | 1288 | EXPORT_SYMBOL_GPL(device_release_driver); |
c95a6b05 | 1289 | |
ed88747c AD |
1290 | /** |
1291 | * device_driver_detach - detach driver from a specific device | |
1292 | * @dev: device to detach driver from | |
1293 | * | |
1294 | * Detach driver from device. Will acquire both @dev lock and @dev->parent | |
1295 | * lock if needed. | |
1296 | */ | |
1297 | void device_driver_detach(struct device *dev) | |
1298 | { | |
1299 | device_release_driver_internal(dev, NULL, dev->parent); | |
1300 | } | |
1301 | ||
07e4a3e2 | 1302 | /** |
1303 | * driver_detach - detach driver from all devices it controls. | |
1304 | * @drv: driver. | |
1305 | */ | |
4a3ad20c | 1306 | void driver_detach(struct device_driver *drv) |
07e4a3e2 | 1307 | { |
8940b4f3 | 1308 | struct device_private *dev_prv; |
4a3ad20c | 1309 | struct device *dev; |
c95a6b05 | 1310 | |
c37d721c AD |
1311 | if (driver_allows_async_probing(drv)) |
1312 | async_synchronize_full(); | |
1313 | ||
c95a6b05 | 1314 | for (;;) { |
e5dd1278 GKH |
1315 | spin_lock(&drv->p->klist_devices.k_lock); |
1316 | if (list_empty(&drv->p->klist_devices.k_list)) { | |
1317 | spin_unlock(&drv->p->klist_devices.k_lock); | |
c95a6b05 AS |
1318 | break; |
1319 | } | |
a3a87d66 | 1320 | dev_prv = list_last_entry(&drv->p->klist_devices.k_list, |
8940b4f3 GKH |
1321 | struct device_private, |
1322 | knode_driver.n_node); | |
1323 | dev = dev_prv->device; | |
c95a6b05 | 1324 | get_device(dev); |
e5dd1278 | 1325 | spin_unlock(&drv->p->klist_devices.k_lock); |
4bdb3550 | 1326 | device_release_driver_internal(dev, drv, dev->parent); |
c95a6b05 AS |
1327 | put_device(dev); |
1328 | } | |
07e4a3e2 | 1329 | } |