blob: c9f54089429bde006fad1135017d49a0422fefa5 [file] [log] [blame]
Greg Kroah-Hartman989d42e2017-11-07 17:30:07 +01001// SPDX-License-Identifier: GPL-2.0
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -08002/*
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -08003 * drivers/base/dd.c - The core device/driver interactions.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -08004 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -08005 * This file contains the (sometimes tricky) code that controls the
6 * interactions between devices and drivers, which primarily includes
7 * driver binding and unbinding.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -08008 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -08009 * 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'.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -080012 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080013 * Copyright (c) 2002-5 Patrick Mochel
14 * Copyright (c) 2002-3 Open Source Development Labs
Greg Kroah-Hartmanb4028432009-05-11 14:16:57 -070015 * Copyright (c) 2007-2009 Greg Kroah-Hartman <gregkh@suse.de>
16 * Copyright (c) 2007-2009 Novell Inc.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -080017 */
18
19#include <linux/device.h>
Arjan van de Ven216773a2009-02-14 01:59:06 +010020#include <linux/delay.h>
Sricharan R09515ef2017-04-10 16:51:01 +053021#include <linux/dma-mapping.h>
Todd Poynor1f5000b2017-07-25 16:31:59 -070022#include <linux/init.h>
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -080023#include <linux/module.h>
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -070024#include <linux/kthread.h>
Andrew Morton735a7ff2006-10-27 11:42:37 -070025#include <linux/wait.h>
Arjan van de Ven216773a2009-02-14 01:59:06 +010026#include <linux/async.h>
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +020027#include <linux/pm_runtime.h>
Linus Walleijab780292013-01-22 10:56:14 -070028#include <linux/pinctrl/devinfo.h>
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -080029
30#include "base.h"
31#include "power/power.h"
32
Grant Likelyd1c34142012-03-05 08:47:41 -070033/*
34 * Deferred Probe infrastructure.
35 *
36 * Sometimes driver probe order matters, but the kernel doesn't always have
37 * dependency information which means some drivers will get probed before a
38 * resource it depends on is available. For example, an SDHCI driver may
39 * first need a GPIO line from an i2c GPIO controller before it can be
40 * initialized. If a required resource is not available yet, a driver can
41 * request probing to be deferred by returning -EPROBE_DEFER from its probe hook
42 *
43 * Deferred probe maintains two lists of devices, a pending list and an active
44 * list. A driver returning -EPROBE_DEFER causes the device to be added to the
45 * pending list. A successful driver probe will trigger moving all devices
46 * from the pending to the active list so that the workqueue will eventually
47 * retry them.
48 *
49 * The deferred_probe_mutex must be held any time the deferred_probe_*_list
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -080050 * of the (struct device*)->p->deferred_probe pointers are manipulated
Grant Likelyd1c34142012-03-05 08:47:41 -070051 */
52static DEFINE_MUTEX(deferred_probe_mutex);
53static LIST_HEAD(deferred_probe_pending_list);
54static LIST_HEAD(deferred_probe_active_list);
Grant Likely58b116b2014-04-29 12:05:22 +010055static atomic_t deferred_trigger_count = ATOMIC_INIT(0);
Todd Poynor1f5000b2017-07-25 16:31:59 -070056static bool initcalls_done;
Grant Likelyd1c34142012-03-05 08:47:41 -070057
Thierry Reding41575332014-08-08 15:56:36 +020058/*
Strashko, Grygorii013c0742015-11-10 11:42:34 +020059 * In some cases, like suspend to RAM or hibernation, It might be reasonable
60 * to prohibit probing of devices as it could be unsafe.
61 * Once defer_all_probes is true all drivers probes will be forcibly deferred.
62 */
63static bool defer_all_probes;
64
65/*
Todd Poynor1f5000b2017-07-25 16:31:59 -070066 * For initcall_debug, show the deferred probes executed in late_initcall
67 * processing.
68 */
69static void deferred_probe_debug(struct device *dev)
70{
71 ktime_t calltime, delta, rettime;
72 unsigned long long duration;
73
74 printk(KERN_DEBUG "deferred probe %s @ %i\n", dev_name(dev),
75 task_pid_nr(current));
76 calltime = ktime_get();
77 bus_probe_device(dev);
78 rettime = ktime_get();
79 delta = ktime_sub(rettime, calltime);
80 duration = (unsigned long long) ktime_to_ns(delta) >> 10;
81 printk(KERN_DEBUG "deferred probe %s returned after %lld usecs\n",
82 dev_name(dev), duration);
83}
84
85/*
Grant Likelyd1c34142012-03-05 08:47:41 -070086 * deferred_probe_work_func() - Retry probing devices in the active list.
87 */
88static void deferred_probe_work_func(struct work_struct *work)
89{
90 struct device *dev;
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -080091 struct device_private *private;
Grant Likelyd1c34142012-03-05 08:47:41 -070092 /*
93 * This block processes every device in the deferred 'active' list.
94 * Each device is removed from the active list and passed to
95 * bus_probe_device() to re-attempt the probe. The loop continues
96 * until every device in the active list is removed and retried.
97 *
98 * Note: Once the device is removed from the list and the mutex is
99 * released, it is possible for the device get freed by another thread
100 * and cause a illegal pointer dereference. This code uses
101 * get/put_device() to ensure the device structure cannot disappear
102 * from under our feet.
103 */
104 mutex_lock(&deferred_probe_mutex);
105 while (!list_empty(&deferred_probe_active_list)) {
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -0800106 private = list_first_entry(&deferred_probe_active_list,
107 typeof(*dev->p), deferred_probe);
108 dev = private->device;
109 list_del_init(&private->deferred_probe);
Grant Likelyd1c34142012-03-05 08:47:41 -0700110
111 get_device(dev);
112
Greg Kroah-Hartman8b0372a2012-03-08 12:20:37 -0800113 /*
114 * Drop the mutex while probing each device; the probe path may
115 * manipulate the deferred list
116 */
Grant Likelyd1c34142012-03-05 08:47:41 -0700117 mutex_unlock(&deferred_probe_mutex);
Mark Brown81535842012-07-05 14:04:44 +0100118
119 /*
120 * Force the device to the end of the dpm_list since
121 * the PM code assumes that the order we add things to
122 * the list is a good order for suspend but deferred
123 * probe makes that very unsafe.
124 */
125 device_pm_lock();
126 device_pm_move_last(dev);
127 device_pm_unlock();
128
Grant Likelyd1c34142012-03-05 08:47:41 -0700129 dev_dbg(dev, "Retrying from deferred list\n");
Todd Poynor1f5000b2017-07-25 16:31:59 -0700130 if (initcall_debug && !initcalls_done)
131 deferred_probe_debug(dev);
132 else
133 bus_probe_device(dev);
Mark Brown81535842012-07-05 14:04:44 +0100134
Grant Likelyd1c34142012-03-05 08:47:41 -0700135 mutex_lock(&deferred_probe_mutex);
136
137 put_device(dev);
138 }
139 mutex_unlock(&deferred_probe_mutex);
140}
141static DECLARE_WORK(deferred_probe_work, deferred_probe_work_func);
142
143static void driver_deferred_probe_add(struct device *dev)
144{
145 mutex_lock(&deferred_probe_mutex);
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -0800146 if (list_empty(&dev->p->deferred_probe)) {
Grant Likelyd1c34142012-03-05 08:47:41 -0700147 dev_dbg(dev, "Added to deferred list\n");
Kuninori Morimoto1d29cfa2012-05-29 18:46:06 -0700148 list_add_tail(&dev->p->deferred_probe, &deferred_probe_pending_list);
Grant Likelyd1c34142012-03-05 08:47:41 -0700149 }
150 mutex_unlock(&deferred_probe_mutex);
151}
152
153void driver_deferred_probe_del(struct device *dev)
154{
155 mutex_lock(&deferred_probe_mutex);
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -0800156 if (!list_empty(&dev->p->deferred_probe)) {
Grant Likelyd1c34142012-03-05 08:47:41 -0700157 dev_dbg(dev, "Removed from deferred list\n");
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -0800158 list_del_init(&dev->p->deferred_probe);
Grant Likelyd1c34142012-03-05 08:47:41 -0700159 }
160 mutex_unlock(&deferred_probe_mutex);
161}
162
163static bool driver_deferred_probe_enable = false;
164/**
165 * driver_deferred_probe_trigger() - Kick off re-probing deferred devices
166 *
167 * This functions moves all devices from the pending list to the active
168 * list and schedules the deferred probe workqueue to process them. It
169 * should be called anytime a driver is successfully bound to a device.
Grant Likely58b116b2014-04-29 12:05:22 +0100170 *
171 * Note, there is a race condition in multi-threaded probe. In the case where
172 * more than one device is probing at the same time, it is possible for one
173 * probe to complete successfully while another is about to defer. If the second
174 * depends on the first, then it will get put on the pending list after the
Shailendra Verma9ba8af62015-05-25 23:46:11 +0530175 * trigger event has already occurred and will be stuck there.
Grant Likely58b116b2014-04-29 12:05:22 +0100176 *
177 * The atomic 'deferred_trigger_count' is used to determine if a successful
178 * trigger has occurred in the midst of probing a driver. If the trigger count
179 * changes in the midst of a probe, then deferred processing should be triggered
180 * again.
Grant Likelyd1c34142012-03-05 08:47:41 -0700181 */
182static void driver_deferred_probe_trigger(void)
183{
184 if (!driver_deferred_probe_enable)
185 return;
186
Greg Kroah-Hartman8b0372a2012-03-08 12:20:37 -0800187 /*
188 * A successful probe means that all the devices in the pending list
Grant Likelyd1c34142012-03-05 08:47:41 -0700189 * should be triggered to be reprobed. Move all the deferred devices
Greg Kroah-Hartman8b0372a2012-03-08 12:20:37 -0800190 * into the active list so they can be retried by the workqueue
191 */
Grant Likelyd1c34142012-03-05 08:47:41 -0700192 mutex_lock(&deferred_probe_mutex);
Grant Likely58b116b2014-04-29 12:05:22 +0100193 atomic_inc(&deferred_trigger_count);
Grant Likelyd1c34142012-03-05 08:47:41 -0700194 list_splice_tail_init(&deferred_probe_pending_list,
195 &deferred_probe_active_list);
196 mutex_unlock(&deferred_probe_mutex);
197
Greg Kroah-Hartman8b0372a2012-03-08 12:20:37 -0800198 /*
199 * Kick the re-probe thread. It may already be scheduled, but it is
200 * safe to kick it again.
201 */
Bhaktipriya Shridhar2c507e42016-08-30 22:45:34 +0530202 schedule_work(&deferred_probe_work);
Grant Likelyd1c34142012-03-05 08:47:41 -0700203}
204
205/**
Strashko, Grygorii013c0742015-11-10 11:42:34 +0200206 * device_block_probing() - Block/defere device's probes
207 *
208 * It will disable probing of devices and defer their probes instead.
209 */
210void device_block_probing(void)
211{
212 defer_all_probes = true;
213 /* sync with probes to avoid races. */
214 wait_for_device_probe();
215}
216
217/**
218 * device_unblock_probing() - Unblock/enable device's probes
219 *
220 * It will restore normal behavior and trigger re-probing of deferred
221 * devices.
222 */
223void device_unblock_probing(void)
224{
225 defer_all_probes = false;
226 driver_deferred_probe_trigger();
227}
228
229/**
Grant Likelyd1c34142012-03-05 08:47:41 -0700230 * deferred_probe_initcall() - Enable probing of deferred devices
231 *
232 * We don't want to get in the way when the bulk of drivers are getting probed.
233 * Instead, this initcall makes sure that deferred probing is delayed until
234 * late_initcall time.
235 */
236static int deferred_probe_initcall(void)
237{
Grant Likelyd1c34142012-03-05 08:47:41 -0700238 driver_deferred_probe_enable = true;
239 driver_deferred_probe_trigger();
Grant Likelyd72cca12013-02-14 18:14:27 +0000240 /* Sort as many dependencies as possible before exiting initcalls */
Bhaktipriya Shridhar2c507e42016-08-30 22:45:34 +0530241 flush_work(&deferred_probe_work);
Todd Poynor1f5000b2017-07-25 16:31:59 -0700242 initcalls_done = true;
Grant Likelyd1c34142012-03-05 08:47:41 -0700243 return 0;
244}
245late_initcall(deferred_probe_initcall);
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800246
Tomeu Vizoso6b9cb422016-01-07 16:46:12 +0100247/**
248 * device_is_bound() - Check if device is bound to a driver
249 * @dev: device to check
250 *
251 * Returns true if passed device has already finished probing successfully
252 * against a driver.
253 *
254 * This function must be called with the device lock held.
255 */
256bool device_is_bound(struct device *dev)
257{
Rafael J. Wysocki3ded9102016-01-12 01:51:44 +0100258 return dev->p && klist_node_attached(&dev->p->knode_driver);
Tomeu Vizoso6b9cb422016-01-07 16:46:12 +0100259}
260
Kay Sievers1901fb22006-10-07 21:55:55 +0200261static void driver_bound(struct device *dev)
262{
Tomeu Vizoso6b9cb422016-01-07 16:46:12 +0100263 if (device_is_bound(dev)) {
Kay Sievers1901fb22006-10-07 21:55:55 +0200264 printk(KERN_WARNING "%s: device %s already bound\n",
Harvey Harrison2b3a3022008-03-04 16:41:05 -0800265 __func__, kobject_name(&dev->kobj));
Kay Sievers1901fb22006-10-07 21:55:55 +0200266 return;
267 }
268
Frank Rowand94f8cc02014-04-16 17:12:30 -0700269 pr_debug("driver: '%s': %s: bound to device '%s'\n", dev->driver->name,
270 __func__, dev_name(dev));
Kay Sievers1901fb22006-10-07 21:55:55 +0200271
Stefani Seiboldfbb88fa2010-03-06 17:50:14 +0100272 klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices);
Rafael J. Wysocki9ed98952016-10-30 17:32:16 +0100273 device_links_driver_bound(dev);
Stefani Seiboldfbb88fa2010-03-06 17:50:14 +0100274
Tomeu Vizosoaa8e54b52016-01-07 16:46:14 +0100275 device_pm_check_callbacks(dev);
276
Greg Kroah-Hartman8b0372a2012-03-08 12:20:37 -0800277 /*
278 * Make sure the device is no longer in one of the deferred lists and
279 * kick off retrying all pending devices
280 */
Grant Likelyd1c34142012-03-05 08:47:41 -0700281 driver_deferred_probe_del(dev);
282 driver_deferred_probe_trigger();
283
Kay Sievers1901fb22006-10-07 21:55:55 +0200284 if (dev->bus)
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700285 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
Kay Sievers1901fb22006-10-07 21:55:55 +0200286 BUS_NOTIFY_BOUND_DRIVER, dev);
Dmitry Torokhov1455cf82017-07-19 17:24:30 -0700287
288 kobject_uevent(&dev->kobj, KOBJ_BIND);
Kay Sievers1901fb22006-10-07 21:55:55 +0200289}
290
Arend van Spriel3c47d192018-01-11 09:36:38 +0100291static ssize_t coredump_store(struct device *dev, struct device_attribute *attr,
292 const char *buf, size_t count)
293{
294 device_lock(dev);
Arend van Spriel1fe56e02018-03-15 10:55:25 +0100295 dev->driver->coredump(dev);
Arend van Spriel3c47d192018-01-11 09:36:38 +0100296 device_unlock(dev);
297
298 return count;
299}
300static DEVICE_ATTR_WO(coredump);
301
Kay Sievers1901fb22006-10-07 21:55:55 +0200302static int driver_sysfs_add(struct device *dev)
303{
304 int ret;
305
Magnus Damm45daef02010-07-23 19:56:18 +0900306 if (dev->bus)
307 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
308 BUS_NOTIFY_BIND_DRIVER, dev);
309
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800310 ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj,
Arend van Spriel3c47d192018-01-11 09:36:38 +0100311 kobject_name(&dev->kobj));
312 if (ret)
313 goto fail;
314
315 ret = sysfs_create_link(&dev->kobj, &dev->driver->p->kobj,
316 "driver");
317 if (ret)
318 goto rm_dev;
319
320 if (!IS_ENABLED(CONFIG_DEV_COREDUMP) || !dev->driver->coredump ||
321 !device_create_file(dev, &dev_attr_coredump))
322 return 0;
323
324 sysfs_remove_link(&dev->kobj, "driver");
325
326rm_dev:
327 sysfs_remove_link(&dev->driver->p->kobj,
Kay Sievers1901fb22006-10-07 21:55:55 +0200328 kobject_name(&dev->kobj));
Arend van Spriel3c47d192018-01-11 09:36:38 +0100329
330fail:
Kay Sievers1901fb22006-10-07 21:55:55 +0200331 return ret;
332}
333
334static void driver_sysfs_remove(struct device *dev)
335{
336 struct device_driver *drv = dev->driver;
337
338 if (drv) {
Arend van Spriel3c47d192018-01-11 09:36:38 +0100339 if (drv->coredump)
340 device_remove_file(dev, &dev_attr_coredump);
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800341 sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj));
Kay Sievers1901fb22006-10-07 21:55:55 +0200342 sysfs_remove_link(&dev->kobj, "driver");
343 }
344}
345
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800346/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800347 * device_bind_driver - bind a driver to one device.
348 * @dev: device.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800349 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800350 * Allow manual attachment of a driver to a device.
351 * Caller must have already set @dev->driver.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800352 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800353 * Note that this does not modify the bus reference count
354 * nor take the bus's rwsem. Please verify those are accounted
355 * for before calling this. (It is ok to call with no other effort
356 * from a driver's probe() method.)
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700357 *
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800358 * This function must be called with the device lock held.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800359 */
Andrew Mortonf86db392006-08-14 22:43:20 -0700360int device_bind_driver(struct device *dev)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800361{
Cornelia Huckcb986b72006-11-27 10:35:12 +0100362 int ret;
363
364 ret = driver_sysfs_add(dev);
365 if (!ret)
366 driver_bound(dev);
Andy Shevchenko14b62572015-12-04 23:49:17 +0200367 else if (dev->bus)
368 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
369 BUS_NOTIFY_DRIVER_NOT_BOUND, dev);
Cornelia Huckcb986b72006-11-27 10:35:12 +0100370 return ret;
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800371}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800372EXPORT_SYMBOL_GPL(device_bind_driver);
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800373
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700374static atomic_t probe_count = ATOMIC_INIT(0);
Andrew Morton735a7ff2006-10-27 11:42:37 -0700375static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue);
376
Adrian Hunter0ff26c62017-11-02 11:22:53 +0200377static void driver_deferred_probe_add_trigger(struct device *dev,
378 int local_trigger_count)
379{
380 driver_deferred_probe_add(dev);
381 /* Did a trigger occur while probing? Need to re-trigger if yes */
382 if (local_trigger_count != atomic_read(&deferred_trigger_count))
383 driver_deferred_probe_trigger();
384}
385
Cornelia Huck21c7f302007-02-05 16:15:25 -0800386static int really_probe(struct device *dev, struct device_driver *drv)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800387{
Strashko, Grygorii013c0742015-11-10 11:42:34 +0200388 int ret = -EPROBE_DEFER;
Grant Likely58b116b2014-04-29 12:05:22 +0100389 int local_trigger_count = atomic_read(&deferred_trigger_count);
Rob Herringc5f06272016-10-11 13:41:02 -0500390 bool test_remove = IS_ENABLED(CONFIG_DEBUG_TEST_DRIVER_REMOVE) &&
391 !drv->suppress_bind_attrs;
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800392
Strashko, Grygorii013c0742015-11-10 11:42:34 +0200393 if (defer_all_probes) {
394 /*
395 * Value of defer_all_probes can be set only by
396 * device_defer_all_probes_enable() which, in turn, will call
397 * wait_for_device_probe() right after that to avoid any races.
398 */
399 dev_dbg(dev, "Driver %s force probe deferral\n", drv->name);
400 driver_deferred_probe_add(dev);
401 return ret;
402 }
403
Rafael J. Wysocki9ed98952016-10-30 17:32:16 +0100404 ret = device_links_check_suppliers(dev);
Adrian Hunter0ff26c62017-11-02 11:22:53 +0200405 if (ret == -EPROBE_DEFER)
406 driver_deferred_probe_add_trigger(dev, local_trigger_count);
Rafael J. Wysocki9ed98952016-10-30 17:32:16 +0100407 if (ret)
408 return ret;
409
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700410 atomic_inc(&probe_count);
Greg Kroah-Hartman7dc72b22007-11-28 23:49:41 -0800411 pr_debug("bus: '%s': %s: probing driver %s with device %s\n",
Kay Sievers1e0b2cf2008-10-30 01:36:48 +0100412 drv->bus->name, __func__, drv->name, dev_name(dev));
Tejun Heo9ac78492007-01-20 16:00:26 +0900413 WARN_ON(!list_empty(&dev->devres_head));
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800414
Rob Herringbea5b152016-08-11 10:20:58 -0500415re_probe:
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800416 dev->driver = drv;
Linus Walleijab780292013-01-22 10:56:14 -0700417
418 /* If using pinctrl, bind pins now before probing */
419 ret = pinctrl_bind_pins(dev);
420 if (ret)
Andy Shevchenko14b62572015-12-04 23:49:17 +0200421 goto pinctrl_bind_failed;
Linus Walleijab780292013-01-22 10:56:14 -0700422
Sricharan R09515ef2017-04-10 16:51:01 +0530423 ret = dma_configure(dev);
424 if (ret)
425 goto dma_failed;
426
Kay Sievers1901fb22006-10-07 21:55:55 +0200427 if (driver_sysfs_add(dev)) {
428 printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n",
Kay Sievers1e0b2cf2008-10-30 01:36:48 +0100429 __func__, dev_name(dev));
Kay Sievers1901fb22006-10-07 21:55:55 +0200430 goto probe_failed;
431 }
432
Rafael J. Wysockie90d5532015-03-20 13:59:27 +0100433 if (dev->pm_domain && dev->pm_domain->activate) {
434 ret = dev->pm_domain->activate(dev);
435 if (ret)
436 goto probe_failed;
437 }
438
Grygorii Strashko52cdbdd2015-07-27 20:43:01 +0300439 /*
440 * Ensure devices are listed in devices_kset in correct order
441 * It's important to move Dev to the end of devices_kset before
442 * calling .probe, because it could be recursive and parent Dev
443 * should always go first
444 */
445 devices_kset_move_last(dev);
446
Russell King594c8282006-01-05 14:29:51 +0000447 if (dev->bus->probe) {
448 ret = dev->bus->probe(dev);
Kay Sievers1901fb22006-10-07 21:55:55 +0200449 if (ret)
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700450 goto probe_failed;
Russell King594c8282006-01-05 14:29:51 +0000451 } else if (drv->probe) {
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700452 ret = drv->probe(dev);
Kay Sievers1901fb22006-10-07 21:55:55 +0200453 if (ret)
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700454 goto probe_failed;
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800455 }
Kay Sievers1901fb22006-10-07 21:55:55 +0200456
Rob Herringbea5b152016-08-11 10:20:58 -0500457 if (test_remove) {
458 test_remove = false;
459
Rob Herringbdacd1b2016-10-11 13:41:03 -0500460 if (dev->bus->remove)
Rob Herringbea5b152016-08-11 10:20:58 -0500461 dev->bus->remove(dev);
462 else if (drv->remove)
463 drv->remove(dev);
464
465 devres_release_all(dev);
466 driver_sysfs_remove(dev);
467 dev->driver = NULL;
468 dev_set_drvdata(dev, NULL);
469 if (dev->pm_domain && dev->pm_domain->dismiss)
470 dev->pm_domain->dismiss(dev);
471 pm_runtime_reinit(dev);
472
473 goto re_probe;
474 }
475
Douglas Andersonef0eebc2015-10-20 21:15:06 -0700476 pinctrl_init_done(dev);
477
Rafael J. Wysockie90d5532015-03-20 13:59:27 +0100478 if (dev->pm_domain && dev->pm_domain->sync)
479 dev->pm_domain->sync(dev);
480
Kay Sievers1901fb22006-10-07 21:55:55 +0200481 driver_bound(dev);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700482 ret = 1;
Greg Kroah-Hartman7dc72b22007-11-28 23:49:41 -0800483 pr_debug("bus: '%s': %s: bound device %s to driver %s\n",
Kay Sievers1e0b2cf2008-10-30 01:36:48 +0100484 drv->bus->name, __func__, dev_name(dev), drv->name);
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700485 goto done;
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700486
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700487probe_failed:
Sricharan R09515ef2017-04-10 16:51:01 +0530488 dma_deconfigure(dev);
489dma_failed:
Andy Shevchenko14b62572015-12-04 23:49:17 +0200490 if (dev->bus)
491 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
492 BUS_NOTIFY_DRIVER_NOT_BOUND, dev);
493pinctrl_bind_failed:
Rafael J. Wysocki9ed98952016-10-30 17:32:16 +0100494 device_links_no_driver(dev);
Tejun Heo9ac78492007-01-20 16:00:26 +0900495 devres_release_all(dev);
Kay Sievers1901fb22006-10-07 21:55:55 +0200496 driver_sysfs_remove(dev);
497 dev->driver = NULL;
Hans de Goede0998d062012-05-23 00:09:34 +0200498 dev_set_drvdata(dev, NULL);
Rafael J. Wysockie90d5532015-03-20 13:59:27 +0100499 if (dev->pm_domain && dev->pm_domain->dismiss)
500 dev->pm_domain->dismiss(dev);
Ulf Hansson5de85b92015-11-18 11:48:39 +0100501 pm_runtime_reinit(dev);
Rafael J. Wysocki08810a42017-10-25 14:12:29 +0200502 dev_pm_set_driver_flags(dev, 0);
Kay Sievers1901fb22006-10-07 21:55:55 +0200503
Sergei Shtylyovbb2b40752015-01-17 22:14:41 +0300504 switch (ret) {
505 case -EPROBE_DEFER:
Grant Likelyd1c34142012-03-05 08:47:41 -0700506 /* Driver requested deferred probing */
Mark Brown13fcffb2015-03-10 11:55:49 +0000507 dev_dbg(dev, "Driver %s requests probe deferral\n", drv->name);
Adrian Hunter0ff26c62017-11-02 11:22:53 +0200508 driver_deferred_probe_add_trigger(dev, local_trigger_count);
Sergei Shtylyovbb2b40752015-01-17 22:14:41 +0300509 break;
510 case -ENODEV:
511 case -ENXIO:
512 pr_debug("%s: probe of %s rejects match %d\n",
513 drv->name, dev_name(dev), ret);
514 break;
515 default:
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700516 /* driver matched but the probe failed */
517 printk(KERN_WARNING
518 "%s: probe of %s failed with error %d\n",
Kay Sievers1e0b2cf2008-10-30 01:36:48 +0100519 drv->name, dev_name(dev), ret);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700520 }
Cornelia Huckc578abb2006-11-27 10:35:10 +0100521 /*
522 * Ignore errors returned by ->probe so that the next driver can try
523 * its luck.
524 */
525 ret = 0;
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700526done:
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700527 atomic_dec(&probe_count);
Andrew Morton735a7ff2006-10-27 11:42:37 -0700528 wake_up(&probe_waitqueue);
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700529 return ret;
530}
531
532/**
533 * driver_probe_done
534 * Determine if the probe sequence is finished or not.
535 *
536 * Should somehow figure out how to use a semaphore, not an atomic variable...
537 */
538int driver_probe_done(void)
539{
Harvey Harrison2b3a3022008-03-04 16:41:05 -0800540 pr_debug("%s: probe_count = %d\n", __func__,
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700541 atomic_read(&probe_count));
542 if (atomic_read(&probe_count))
543 return -EBUSY;
544 return 0;
545}
546
547/**
Arjan van de Ven216773a2009-02-14 01:59:06 +0100548 * wait_for_device_probe
549 * Wait for device probing to be completed.
Arjan van de Ven216773a2009-02-14 01:59:06 +0100550 */
Ming Leib23530e2009-02-21 16:45:07 +0800551void wait_for_device_probe(void)
Arjan van de Ven216773a2009-02-14 01:59:06 +0100552{
Strashko, Grygorii013c0742015-11-10 11:42:34 +0200553 /* wait for the deferred probe workqueue to finish */
Bhaktipriya Shridhar2c507e42016-08-30 22:45:34 +0530554 flush_work(&deferred_probe_work);
Strashko, Grygorii013c0742015-11-10 11:42:34 +0200555
Arjan van de Ven216773a2009-02-14 01:59:06 +0100556 /* wait for the known devices to complete their probing */
Ming Leib23530e2009-02-21 16:45:07 +0800557 wait_event(probe_waitqueue, atomic_read(&probe_count) == 0);
Arjan van de Ven216773a2009-02-14 01:59:06 +0100558 async_synchronize_full();
Arjan van de Ven216773a2009-02-14 01:59:06 +0100559}
Arjan van de Vend4d52912009-04-21 13:32:54 -0700560EXPORT_SYMBOL_GPL(wait_for_device_probe);
Arjan van de Ven216773a2009-02-14 01:59:06 +0100561
562/**
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700563 * driver_probe_device - attempt to bind device & driver together
564 * @drv: driver to bind a device to
565 * @dev: device to try to bind to the driver
566 *
Ming Lei49b420a2009-01-21 23:27:47 +0800567 * This function returns -ENODEV if the device is not registered,
André Goddard Rosaaf901ca2009-11-14 13:09:05 -0200568 * 1 if the device is bound successfully and 0 otherwise.
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700569 *
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800570 * This function must be called with @dev lock held. When called for a
571 * USB interface, @dev->parent lock must be held as well.
Rafael J. Wysockiddef08d2015-07-27 18:03:58 +0300572 *
573 * If the device has a parent, runtime-resume the parent before driver probing.
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700574 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800575int driver_probe_device(struct device_driver *drv, struct device *dev)
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700576{
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700577 int ret = 0;
578
Alan Sternf2eaae12006-09-18 16:22:34 -0400579 if (!device_is_registered(dev))
580 return -ENODEV;
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700581
Greg Kroah-Hartman7dc72b22007-11-28 23:49:41 -0800582 pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
Kay Sievers1e0b2cf2008-10-30 01:36:48 +0100583 drv->bus->name, __func__, dev_name(dev), drv->name);
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700584
Rafael J. Wysocki21d5c572016-10-30 17:32:31 +0100585 pm_runtime_get_suppliers(dev);
Rafael J. Wysockiddef08d2015-07-27 18:03:58 +0300586 if (dev->parent)
587 pm_runtime_get_sync(dev->parent);
588
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +0200589 pm_runtime_barrier(dev);
Cornelia Huck21c7f302007-02-05 16:15:25 -0800590 ret = really_probe(dev, drv);
Ulf Hanssonfa180eb2013-04-10 17:00:48 +0200591 pm_request_idle(dev);
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700592
Rafael J. Wysockiddef08d2015-07-27 18:03:58 +0300593 if (dev->parent)
594 pm_runtime_put(dev->parent);
595
Rafael J. Wysocki21d5c572016-10-30 17:32:31 +0100596 pm_runtime_put_suppliers(dev);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700597 return ret;
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800598}
599
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700600bool driver_allows_async_probing(struct device_driver *drv)
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800601{
Luis R. Rodriguezd173a132015-03-30 16:20:06 -0700602 switch (drv->probe_type) {
603 case PROBE_PREFER_ASYNCHRONOUS:
Luis R. Rodriguezf2411da2015-03-30 16:20:05 -0700604 return true;
605
Luis R. Rodriguezd173a132015-03-30 16:20:06 -0700606 case PROBE_FORCE_SYNCHRONOUS:
607 return false;
Luis R. Rodriguezf2411da2015-03-30 16:20:05 -0700608
Luis R. Rodriguezd173a132015-03-30 16:20:06 -0700609 default:
Dmitry Torokhov80c6e142015-05-21 15:49:37 -0700610 if (module_requested_async_probing(drv->owner))
Luis R. Rodriguezd173a132015-03-30 16:20:06 -0700611 return true;
612
613 return false;
614 }
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700615}
616
617struct device_attach_data {
618 struct device *dev;
619
620 /*
621 * Indicates whether we are are considering asynchronous probing or
622 * not. Only initial binding after device or driver registration
623 * (including deferral processing) may be done asynchronously, the
624 * rest is always synchronous, as we expect it is being done by
625 * request from userspace.
626 */
627 bool check_async;
628
629 /*
630 * Indicates if we are binding synchronous or asynchronous drivers.
631 * When asynchronous probing is enabled we'll execute 2 passes
632 * over drivers: first pass doing synchronous probing and second
633 * doing asynchronous probing (if synchronous did not succeed -
634 * most likely because there was no driver requiring synchronous
635 * probing - and we found asynchronous driver during first pass).
636 * The 2 passes are done because we can't shoot asynchronous
637 * probe for given device and driver from bus_for_each_drv() since
638 * driver pointer is not guaranteed to stay valid once
639 * bus_for_each_drv() iterates to the next driver on the bus.
640 */
641 bool want_async;
642
643 /*
644 * We'll set have_async to 'true' if, while scanning for matching
645 * driver, we'll encounter one that requests asynchronous probing.
646 */
647 bool have_async;
648};
649
650static int __device_attach_driver(struct device_driver *drv, void *_data)
651{
652 struct device_attach_data *data = _data;
653 struct device *dev = data->dev;
654 bool async_allowed;
Tomeu Vizoso656b8032016-02-15 09:25:06 +0100655 int ret;
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700656
657 /*
658 * Check if device has already been claimed. This may
659 * happen with driver loading, device discovery/registration,
660 * and deferred probe processing happens all at once with
661 * multiple threads.
662 */
663 if (dev->driver)
664 return -EBUSY;
Ming Lei49b420a2009-01-21 23:27:47 +0800665
Tomeu Vizoso656b8032016-02-15 09:25:06 +0100666 ret = driver_match_device(drv, dev);
667 if (ret == 0) {
668 /* no match */
Ming Lei49b420a2009-01-21 23:27:47 +0800669 return 0;
Tomeu Vizoso656b8032016-02-15 09:25:06 +0100670 } else if (ret == -EPROBE_DEFER) {
671 dev_dbg(dev, "Device match requests probe deferral\n");
672 driver_deferred_probe_add(dev);
673 } else if (ret < 0) {
674 dev_dbg(dev, "Bus failed to match device: %d", ret);
675 return ret;
676 } /* ret > 0 means positive match */
Ming Lei49b420a2009-01-21 23:27:47 +0800677
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700678 async_allowed = driver_allows_async_probing(drv);
679
680 if (async_allowed)
681 data->have_async = true;
682
683 if (data->check_async && async_allowed != data->want_async)
684 return 0;
685
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700686 return driver_probe_device(drv, dev);
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800687}
688
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700689static void __device_attach_async_helper(void *_dev, async_cookie_t cookie)
690{
691 struct device *dev = _dev;
692 struct device_attach_data data = {
693 .dev = dev,
694 .check_async = true,
695 .want_async = true,
696 };
697
698 device_lock(dev);
699
Rafael J. Wysockiddef08d2015-07-27 18:03:58 +0300700 if (dev->parent)
701 pm_runtime_get_sync(dev->parent);
702
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700703 bus_for_each_drv(dev->bus, NULL, &data, __device_attach_driver);
704 dev_dbg(dev, "async probe completed\n");
705
706 pm_request_idle(dev);
707
Rafael J. Wysockiddef08d2015-07-27 18:03:58 +0300708 if (dev->parent)
709 pm_runtime_put(dev->parent);
710
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700711 device_unlock(dev);
712
713 put_device(dev);
714}
715
Dmitry Torokhov802a87f2015-05-20 16:36:31 -0700716static int __device_attach(struct device *dev, bool allow_async)
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700717{
718 int ret = 0;
719
720 device_lock(dev);
721 if (dev->driver) {
Tomeu Vizoso6b9cb422016-01-07 16:46:12 +0100722 if (device_is_bound(dev)) {
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700723 ret = 1;
724 goto out_unlock;
725 }
726 ret = device_bind_driver(dev);
727 if (ret == 0)
728 ret = 1;
729 else {
730 dev->driver = NULL;
731 ret = 0;
732 }
733 } else {
734 struct device_attach_data data = {
735 .dev = dev,
736 .check_async = allow_async,
737 .want_async = false,
738 };
739
Rafael J. Wysockiddef08d2015-07-27 18:03:58 +0300740 if (dev->parent)
741 pm_runtime_get_sync(dev->parent);
742
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700743 ret = bus_for_each_drv(dev->bus, NULL, &data,
744 __device_attach_driver);
745 if (!ret && allow_async && data.have_async) {
746 /*
747 * If we could not find appropriate driver
748 * synchronously and we are allowed to do
749 * async probes and there are drivers that
750 * want to probe asynchronously, we'll
751 * try them.
752 */
753 dev_dbg(dev, "scheduling asynchronous probe\n");
754 get_device(dev);
755 async_schedule(__device_attach_async_helper, dev);
756 } else {
757 pm_request_idle(dev);
758 }
Rafael J. Wysockiddef08d2015-07-27 18:03:58 +0300759
760 if (dev->parent)
761 pm_runtime_put(dev->parent);
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700762 }
763out_unlock:
764 device_unlock(dev);
765 return ret;
766}
767
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800768/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800769 * device_attach - try to attach device to a driver.
770 * @dev: device.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800771 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800772 * Walk the list of drivers that the bus has and call
773 * driver_probe_device() for each pair. If a compatible
774 * pair is found, break out and return.
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700775 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800776 * Returns 1 if the device was bound to a driver;
Dmitry Torokhov59a3cd72009-05-05 20:38:28 -0700777 * 0 if no matching driver was found;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800778 * -ENODEV if the device is not registered.
Alan Sternbf74ad52005-11-17 16:54:12 -0500779 *
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800780 * When called for a USB interface, @dev->parent lock must be held.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800781 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800782int device_attach(struct device *dev)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800783{
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700784 return __device_attach(dev, false);
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800785}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800786EXPORT_SYMBOL_GPL(device_attach);
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800787
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700788void device_initial_probe(struct device *dev)
789{
790 __device_attach(dev, true);
791}
792
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800793static int __driver_attach(struct device *dev, void *data)
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800794{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800795 struct device_driver *drv = data;
Tomeu Vizoso656b8032016-02-15 09:25:06 +0100796 int ret;
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800797
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700798 /*
799 * Lock device and try to bind to it. We drop the error
800 * here and always return 0, because we need to keep trying
801 * to bind to devices and some drivers will return an error
802 * simply if it didn't support the device.
803 *
804 * driver_probe_device() will spit a warning if there
805 * is an error.
806 */
807
Tomeu Vizoso656b8032016-02-15 09:25:06 +0100808 ret = driver_match_device(drv, dev);
809 if (ret == 0) {
810 /* no match */
Arjan van de Ven6cd49582008-09-14 08:32:06 -0700811 return 0;
Tomeu Vizoso656b8032016-02-15 09:25:06 +0100812 } else if (ret == -EPROBE_DEFER) {
813 dev_dbg(dev, "Device match requests probe deferral\n");
814 driver_deferred_probe_add(dev);
815 } else if (ret < 0) {
816 dev_dbg(dev, "Bus failed to match device: %d", ret);
817 return ret;
818 } /* ret > 0 means positive match */
Arjan van de Ven6cd49582008-09-14 08:32:06 -0700819
Alan Sternbf74ad52005-11-17 16:54:12 -0500820 if (dev->parent) /* Needed for USB */
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800821 device_lock(dev->parent);
822 device_lock(dev);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700823 if (!dev->driver)
824 driver_probe_device(drv, dev);
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800825 device_unlock(dev);
Alan Sternbf74ad52005-11-17 16:54:12 -0500826 if (dev->parent)
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800827 device_unlock(dev->parent);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700828
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800829 return 0;
830}
831
832/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800833 * driver_attach - try to bind driver to devices.
834 * @drv: driver.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800835 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800836 * Walk the list of devices that the bus has on it and try to
837 * match the driver with each one. If driver_probe_device()
838 * returns 0 and the @dev->driver is set, we've found a
839 * compatible pair.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800840 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800841int driver_attach(struct device_driver *drv)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800842{
Andrew Mortonf86db392006-08-14 22:43:20 -0700843 return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach);
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800844}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800845EXPORT_SYMBOL_GPL(driver_attach);
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800846
Stefan Richterab71c6f2007-06-17 11:02:12 +0200847/*
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800848 * __device_release_driver() must be called with @dev lock held.
849 * When called for a USB interface, @dev->parent lock must be held as well.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800850 */
Rafael J. Wysocki9ed98952016-10-30 17:32:16 +0100851static void __device_release_driver(struct device *dev, struct device *parent)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800852{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800853 struct device_driver *drv;
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800854
Alan Sternef2c5172007-11-16 11:57:28 -0500855 drv = dev->driver;
Alan Sternc95a6b02005-05-06 15:38:33 -0400856 if (drv) {
Dmitry Torokhov765230b2015-03-30 16:20:04 -0700857 if (driver_allows_async_probing(drv))
858 async_synchronize_full();
859
Rafael J. Wysocki9ed98952016-10-30 17:32:16 +0100860 while (device_links_busy(dev)) {
861 device_unlock(dev);
862 if (parent)
863 device_unlock(parent);
864
865 device_links_unbind_consumers(dev);
866 if (parent)
867 device_lock(parent);
868
869 device_lock(dev);
870 /*
871 * A concurrent invocation of the same function might
872 * have released the driver successfully while this one
873 * was waiting, so check for that.
874 */
875 if (dev->driver != drv)
876 return;
877 }
878
Rafael J. Wysockie1866b32011-04-29 00:33:45 +0200879 pm_runtime_get_sync(dev);
Rafael J. Wysocki21d5c572016-10-30 17:32:31 +0100880 pm_runtime_clean_up_links(dev);
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +0200881
Kay Sievers1901fb22006-10-07 21:55:55 +0200882 driver_sysfs_remove(dev);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700883
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000884 if (dev->bus)
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700885 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000886 BUS_NOTIFY_UNBIND_DRIVER,
887 dev);
888
Rafael J. Wysockibaab52d2013-11-07 01:51:15 +0100889 pm_runtime_put_sync(dev);
Rafael J. Wysockie1866b32011-04-29 00:33:45 +0200890
Alan Stern0f836ca2006-03-31 11:52:25 -0500891 if (dev->bus && dev->bus->remove)
Russell King594c8282006-01-05 14:29:51 +0000892 dev->bus->remove(dev);
893 else if (drv->remove)
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700894 drv->remove(dev);
Rafael J. Wysocki9ed98952016-10-30 17:32:16 +0100895
896 device_links_driver_cleanup(dev);
Sricharan R09515ef2017-04-10 16:51:01 +0530897 dma_deconfigure(dev);
898
Tejun Heo9ac78492007-01-20 16:00:26 +0900899 devres_release_all(dev);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700900 dev->driver = NULL;
Hans de Goede0998d062012-05-23 00:09:34 +0200901 dev_set_drvdata(dev, NULL);
Rafael J. Wysockie90d5532015-03-20 13:59:27 +0100902 if (dev->pm_domain && dev->pm_domain->dismiss)
903 dev->pm_domain->dismiss(dev);
Ulf Hansson5de85b92015-11-18 11:48:39 +0100904 pm_runtime_reinit(dev);
Rafael J. Wysocki08810a42017-10-25 14:12:29 +0200905 dev_pm_set_driver_flags(dev, 0);
Rafael J. Wysockie90d5532015-03-20 13:59:27 +0100906
Greg Kroah-Hartman8940b4f2008-12-16 12:25:49 -0800907 klist_remove(&dev->p->knode_driver);
Tomeu Vizosoaa8e54b52016-01-07 16:46:14 +0100908 device_pm_check_callbacks(dev);
Joerg Roedel309b7d62009-04-24 14:57:00 +0200909 if (dev->bus)
910 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
911 BUS_NOTIFY_UNBOUND_DRIVER,
912 dev);
Dmitry Torokhov1455cf82017-07-19 17:24:30 -0700913
914 kobject_uevent(&dev->kobj, KOBJ_UNBIND);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700915 }
Alan Sternc95a6b02005-05-06 15:38:33 -0400916}
917
Rafael J. Wysocki9ed98952016-10-30 17:32:16 +0100918void device_release_driver_internal(struct device *dev,
919 struct device_driver *drv,
920 struct device *parent)
Rafael J. Wysocki4bdb3552016-10-10 14:37:56 +0200921{
922 if (parent)
923 device_lock(parent);
924
925 device_lock(dev);
926 if (!drv || drv == dev->driver)
Rafael J. Wysocki9ed98952016-10-30 17:32:16 +0100927 __device_release_driver(dev, parent);
Rafael J. Wysocki4bdb3552016-10-10 14:37:56 +0200928
929 device_unlock(dev);
930 if (parent)
931 device_unlock(parent);
932}
933
Stefan Richterab71c6f2007-06-17 11:02:12 +0200934/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800935 * device_release_driver - manually detach device from driver.
936 * @dev: device.
Stefan Richterab71c6f2007-06-17 11:02:12 +0200937 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800938 * Manually detach device from driver.
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800939 * When called for a USB interface, @dev->parent lock must be held.
Rafael J. Wysocki9ed98952016-10-30 17:32:16 +0100940 *
941 * If this function is to be called with @dev->parent lock held, ensure that
942 * the device's consumers are unbound in advance or that their locks can be
943 * acquired under the @dev->parent lock.
Stefan Richterab71c6f2007-06-17 11:02:12 +0200944 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800945void device_release_driver(struct device *dev)
Alan Sternc95a6b02005-05-06 15:38:33 -0400946{
947 /*
948 * If anyone calls device_release_driver() recursively from
949 * within their ->remove callback for the same device, they
950 * will deadlock right here.
951 */
Rafael J. Wysocki4bdb3552016-10-10 14:37:56 +0200952 device_release_driver_internal(dev, NULL, NULL);
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800953}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800954EXPORT_SYMBOL_GPL(device_release_driver);
mochel@digitalimplant.org94e7b1c52005-03-21 12:25:36 -0800955
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800956/**
957 * driver_detach - detach driver from all devices it controls.
958 * @drv: driver.
959 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800960void driver_detach(struct device_driver *drv)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800961{
Greg Kroah-Hartman8940b4f2008-12-16 12:25:49 -0800962 struct device_private *dev_prv;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800963 struct device *dev;
Alan Sternc95a6b02005-05-06 15:38:33 -0400964
965 for (;;) {
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800966 spin_lock(&drv->p->klist_devices.k_lock);
967 if (list_empty(&drv->p->klist_devices.k_list)) {
968 spin_unlock(&drv->p->klist_devices.k_lock);
Alan Sternc95a6b02005-05-06 15:38:33 -0400969 break;
970 }
Greg Kroah-Hartman8940b4f2008-12-16 12:25:49 -0800971 dev_prv = list_entry(drv->p->klist_devices.k_list.prev,
972 struct device_private,
973 knode_driver.n_node);
974 dev = dev_prv->device;
Alan Sternc95a6b02005-05-06 15:38:33 -0400975 get_device(dev);
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800976 spin_unlock(&drv->p->klist_devices.k_lock);
Rafael J. Wysocki4bdb3552016-10-10 14:37:56 +0200977 device_release_driver_internal(dev, drv, dev->parent);
Alan Sternc95a6b02005-05-06 15:38:33 -0400978 put_device(dev);
979 }
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800980}