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mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -08001/*
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -08002 * drivers/base/dd.c - The core device/driver interactions.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -08003 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -08004 * This file contains the (sometimes tricky) code that controls the
5 * interactions between devices and drivers, which primarily includes
6 * driver binding and unbinding.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -08007 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -08008 * All of this code used to exist in drivers/base/bus.c, but was
9 * relocated to here in the name of compartmentalization (since it wasn't
10 * strictly code just for the 'struct bus_type'.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -080011 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080012 * Copyright (c) 2002-5 Patrick Mochel
13 * Copyright (c) 2002-3 Open Source Development Labs
Greg Kroah-Hartmanb4028432009-05-11 14:16:57 -070014 * Copyright (c) 2007-2009 Greg Kroah-Hartman <gregkh@suse.de>
15 * Copyright (c) 2007-2009 Novell Inc.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -080016 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -080017 * This file is released under the GPLv2
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -080018 */
19
20#include <linux/device.h>
Arjan van de Ven216773a2009-02-14 01:59:06 +010021#include <linux/delay.h>
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -080022#include <linux/module.h>
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -070023#include <linux/kthread.h>
Andrew Morton735a7ff2006-10-27 11:42:37 -070024#include <linux/wait.h>
Arjan van de Ven216773a2009-02-14 01:59:06 +010025#include <linux/async.h>
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +020026#include <linux/pm_runtime.h>
Linus Walleijab780292013-01-22 10:56:14 -070027#include <linux/pinctrl/devinfo.h>
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -080028
29#include "base.h"
30#include "power/power.h"
31
Grant Likelyd1c34142012-03-05 08:47:41 -070032/*
33 * Deferred Probe infrastructure.
34 *
35 * Sometimes driver probe order matters, but the kernel doesn't always have
36 * dependency information which means some drivers will get probed before a
37 * resource it depends on is available. For example, an SDHCI driver may
38 * first need a GPIO line from an i2c GPIO controller before it can be
39 * initialized. If a required resource is not available yet, a driver can
40 * request probing to be deferred by returning -EPROBE_DEFER from its probe hook
41 *
42 * Deferred probe maintains two lists of devices, a pending list and an active
43 * list. A driver returning -EPROBE_DEFER causes the device to be added to the
44 * pending list. A successful driver probe will trigger moving all devices
45 * from the pending to the active list so that the workqueue will eventually
46 * retry them.
47 *
48 * The deferred_probe_mutex must be held any time the deferred_probe_*_list
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -080049 * of the (struct device*)->p->deferred_probe pointers are manipulated
Grant Likelyd1c34142012-03-05 08:47:41 -070050 */
51static DEFINE_MUTEX(deferred_probe_mutex);
52static LIST_HEAD(deferred_probe_pending_list);
53static LIST_HEAD(deferred_probe_active_list);
54static struct workqueue_struct *deferred_wq;
55
56/**
57 * deferred_probe_work_func() - Retry probing devices in the active list.
58 */
59static void deferred_probe_work_func(struct work_struct *work)
60{
61 struct device *dev;
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -080062 struct device_private *private;
Grant Likelyd1c34142012-03-05 08:47:41 -070063 /*
64 * This block processes every device in the deferred 'active' list.
65 * Each device is removed from the active list and passed to
66 * bus_probe_device() to re-attempt the probe. The loop continues
67 * until every device in the active list is removed and retried.
68 *
69 * Note: Once the device is removed from the list and the mutex is
70 * released, it is possible for the device get freed by another thread
71 * and cause a illegal pointer dereference. This code uses
72 * get/put_device() to ensure the device structure cannot disappear
73 * from under our feet.
74 */
75 mutex_lock(&deferred_probe_mutex);
76 while (!list_empty(&deferred_probe_active_list)) {
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -080077 private = list_first_entry(&deferred_probe_active_list,
78 typeof(*dev->p), deferred_probe);
79 dev = private->device;
80 list_del_init(&private->deferred_probe);
Grant Likelyd1c34142012-03-05 08:47:41 -070081
82 get_device(dev);
83
Greg Kroah-Hartman8b0372a2012-03-08 12:20:37 -080084 /*
85 * Drop the mutex while probing each device; the probe path may
86 * manipulate the deferred list
87 */
Grant Likelyd1c34142012-03-05 08:47:41 -070088 mutex_unlock(&deferred_probe_mutex);
Mark Brown81535842012-07-05 14:04:44 +010089
90 /*
91 * Force the device to the end of the dpm_list since
92 * the PM code assumes that the order we add things to
93 * the list is a good order for suspend but deferred
94 * probe makes that very unsafe.
95 */
96 device_pm_lock();
97 device_pm_move_last(dev);
98 device_pm_unlock();
99
Grant Likelyd1c34142012-03-05 08:47:41 -0700100 dev_dbg(dev, "Retrying from deferred list\n");
101 bus_probe_device(dev);
Mark Brown81535842012-07-05 14:04:44 +0100102
Grant Likelyd1c34142012-03-05 08:47:41 -0700103 mutex_lock(&deferred_probe_mutex);
104
105 put_device(dev);
106 }
107 mutex_unlock(&deferred_probe_mutex);
108}
109static DECLARE_WORK(deferred_probe_work, deferred_probe_work_func);
110
111static void driver_deferred_probe_add(struct device *dev)
112{
113 mutex_lock(&deferred_probe_mutex);
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -0800114 if (list_empty(&dev->p->deferred_probe)) {
Grant Likelyd1c34142012-03-05 08:47:41 -0700115 dev_dbg(dev, "Added to deferred list\n");
Kuninori Morimoto1d29cfa52012-05-29 18:46:06 -0700116 list_add_tail(&dev->p->deferred_probe, &deferred_probe_pending_list);
Grant Likelyd1c34142012-03-05 08:47:41 -0700117 }
118 mutex_unlock(&deferred_probe_mutex);
119}
120
121void driver_deferred_probe_del(struct device *dev)
122{
123 mutex_lock(&deferred_probe_mutex);
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -0800124 if (!list_empty(&dev->p->deferred_probe)) {
Grant Likelyd1c34142012-03-05 08:47:41 -0700125 dev_dbg(dev, "Removed from deferred list\n");
Greg Kroah-Hartmanef8a3fd2012-03-08 12:17:22 -0800126 list_del_init(&dev->p->deferred_probe);
Grant Likelyd1c34142012-03-05 08:47:41 -0700127 }
128 mutex_unlock(&deferred_probe_mutex);
129}
130
131static bool driver_deferred_probe_enable = false;
132/**
133 * driver_deferred_probe_trigger() - Kick off re-probing deferred devices
134 *
135 * This functions moves all devices from the pending list to the active
136 * list and schedules the deferred probe workqueue to process them. It
137 * should be called anytime a driver is successfully bound to a device.
138 */
139static void driver_deferred_probe_trigger(void)
140{
141 if (!driver_deferred_probe_enable)
142 return;
143
Greg Kroah-Hartman8b0372a2012-03-08 12:20:37 -0800144 /*
145 * A successful probe means that all the devices in the pending list
Grant Likelyd1c34142012-03-05 08:47:41 -0700146 * should be triggered to be reprobed. Move all the deferred devices
Greg Kroah-Hartman8b0372a2012-03-08 12:20:37 -0800147 * into the active list so they can be retried by the workqueue
148 */
Grant Likelyd1c34142012-03-05 08:47:41 -0700149 mutex_lock(&deferred_probe_mutex);
150 list_splice_tail_init(&deferred_probe_pending_list,
151 &deferred_probe_active_list);
152 mutex_unlock(&deferred_probe_mutex);
153
Greg Kroah-Hartman8b0372a2012-03-08 12:20:37 -0800154 /*
155 * Kick the re-probe thread. It may already be scheduled, but it is
156 * safe to kick it again.
157 */
Grant Likelyd1c34142012-03-05 08:47:41 -0700158 queue_work(deferred_wq, &deferred_probe_work);
159}
160
161/**
162 * deferred_probe_initcall() - Enable probing of deferred devices
163 *
164 * We don't want to get in the way when the bulk of drivers are getting probed.
165 * Instead, this initcall makes sure that deferred probing is delayed until
166 * late_initcall time.
167 */
168static int deferred_probe_initcall(void)
169{
170 deferred_wq = create_singlethread_workqueue("deferwq");
171 if (WARN_ON(!deferred_wq))
172 return -ENOMEM;
173
174 driver_deferred_probe_enable = true;
175 driver_deferred_probe_trigger();
Grant Likelyd72cca12013-02-14 18:14:27 +0000176 /* Sort as many dependencies as possible before exiting initcalls */
177 flush_workqueue(deferred_wq);
Grant Likelyd1c34142012-03-05 08:47:41 -0700178 return 0;
179}
180late_initcall(deferred_probe_initcall);
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800181
Kay Sievers1901fb22006-10-07 21:55:55 +0200182static void driver_bound(struct device *dev)
183{
Greg Kroah-Hartman8940b4f2008-12-16 12:25:49 -0800184 if (klist_node_attached(&dev->p->knode_driver)) {
Kay Sievers1901fb22006-10-07 21:55:55 +0200185 printk(KERN_WARNING "%s: device %s already bound\n",
Harvey Harrison2b3a3022008-03-04 16:41:05 -0800186 __func__, kobject_name(&dev->kobj));
Kay Sievers1901fb22006-10-07 21:55:55 +0200187 return;
188 }
189
Kay Sievers1e0b2cf2008-10-30 01:36:48 +0100190 pr_debug("driver: '%s': %s: bound to device '%s'\n", dev_name(dev),
Harvey Harrison2b3a3022008-03-04 16:41:05 -0800191 __func__, dev->driver->name);
Kay Sievers1901fb22006-10-07 21:55:55 +0200192
Stefani Seiboldfbb88fa2010-03-06 17:50:14 +0100193 klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices);
194
Greg Kroah-Hartman8b0372a2012-03-08 12:20:37 -0800195 /*
196 * Make sure the device is no longer in one of the deferred lists and
197 * kick off retrying all pending devices
198 */
Grant Likelyd1c34142012-03-05 08:47:41 -0700199 driver_deferred_probe_del(dev);
200 driver_deferred_probe_trigger();
201
Kay Sievers1901fb22006-10-07 21:55:55 +0200202 if (dev->bus)
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700203 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
Kay Sievers1901fb22006-10-07 21:55:55 +0200204 BUS_NOTIFY_BOUND_DRIVER, dev);
Kay Sievers1901fb22006-10-07 21:55:55 +0200205}
206
207static int driver_sysfs_add(struct device *dev)
208{
209 int ret;
210
Magnus Damm45daef02010-07-23 19:56:18 +0900211 if (dev->bus)
212 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
213 BUS_NOTIFY_BIND_DRIVER, dev);
214
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800215 ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj,
Kay Sievers1901fb22006-10-07 21:55:55 +0200216 kobject_name(&dev->kobj));
217 if (ret == 0) {
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800218 ret = sysfs_create_link(&dev->kobj, &dev->driver->p->kobj,
Kay Sievers1901fb22006-10-07 21:55:55 +0200219 "driver");
220 if (ret)
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800221 sysfs_remove_link(&dev->driver->p->kobj,
Kay Sievers1901fb22006-10-07 21:55:55 +0200222 kobject_name(&dev->kobj));
223 }
224 return ret;
225}
226
227static void driver_sysfs_remove(struct device *dev)
228{
229 struct device_driver *drv = dev->driver;
230
231 if (drv) {
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800232 sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj));
Kay Sievers1901fb22006-10-07 21:55:55 +0200233 sysfs_remove_link(&dev->kobj, "driver");
234 }
235}
236
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800237/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800238 * device_bind_driver - bind a driver to one device.
239 * @dev: device.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800240 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800241 * Allow manual attachment of a driver to a device.
242 * Caller must have already set @dev->driver.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800243 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800244 * Note that this does not modify the bus reference count
245 * nor take the bus's rwsem. Please verify those are accounted
246 * for before calling this. (It is ok to call with no other effort
247 * from a driver's probe() method.)
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700248 *
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800249 * This function must be called with the device lock held.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800250 */
Andrew Mortonf86db392006-08-14 22:43:20 -0700251int device_bind_driver(struct device *dev)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800252{
Cornelia Huckcb986b72006-11-27 10:35:12 +0100253 int ret;
254
255 ret = driver_sysfs_add(dev);
256 if (!ret)
257 driver_bound(dev);
258 return ret;
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800259}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800260EXPORT_SYMBOL_GPL(device_bind_driver);
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800261
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700262static atomic_t probe_count = ATOMIC_INIT(0);
Andrew Morton735a7ff2006-10-27 11:42:37 -0700263static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue);
264
Cornelia Huck21c7f302007-02-05 16:15:25 -0800265static int really_probe(struct device *dev, struct device_driver *drv)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800266{
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700267 int ret = 0;
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800268
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700269 atomic_inc(&probe_count);
Greg Kroah-Hartman7dc72b22007-11-28 23:49:41 -0800270 pr_debug("bus: '%s': %s: probing driver %s with device %s\n",
Kay Sievers1e0b2cf2008-10-30 01:36:48 +0100271 drv->bus->name, __func__, drv->name, dev_name(dev));
Tejun Heo9ac78492007-01-20 16:00:26 +0900272 WARN_ON(!list_empty(&dev->devres_head));
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800273
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800274 dev->driver = drv;
Linus Walleijab780292013-01-22 10:56:14 -0700275
276 /* If using pinctrl, bind pins now before probing */
277 ret = pinctrl_bind_pins(dev);
278 if (ret)
279 goto probe_failed;
280
Kay Sievers1901fb22006-10-07 21:55:55 +0200281 if (driver_sysfs_add(dev)) {
282 printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n",
Kay Sievers1e0b2cf2008-10-30 01:36:48 +0100283 __func__, dev_name(dev));
Kay Sievers1901fb22006-10-07 21:55:55 +0200284 goto probe_failed;
285 }
286
Russell King594c8282006-01-05 14:29:51 +0000287 if (dev->bus->probe) {
288 ret = dev->bus->probe(dev);
Kay Sievers1901fb22006-10-07 21:55:55 +0200289 if (ret)
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700290 goto probe_failed;
Russell King594c8282006-01-05 14:29:51 +0000291 } else if (drv->probe) {
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700292 ret = drv->probe(dev);
Kay Sievers1901fb22006-10-07 21:55:55 +0200293 if (ret)
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700294 goto probe_failed;
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800295 }
Kay Sievers1901fb22006-10-07 21:55:55 +0200296
297 driver_bound(dev);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700298 ret = 1;
Greg Kroah-Hartman7dc72b22007-11-28 23:49:41 -0800299 pr_debug("bus: '%s': %s: bound device %s to driver %s\n",
Kay Sievers1e0b2cf2008-10-30 01:36:48 +0100300 drv->bus->name, __func__, dev_name(dev), drv->name);
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700301 goto done;
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700302
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700303probe_failed:
Tejun Heo9ac78492007-01-20 16:00:26 +0900304 devres_release_all(dev);
Kay Sievers1901fb22006-10-07 21:55:55 +0200305 driver_sysfs_remove(dev);
306 dev->driver = NULL;
Hans de Goede0998d062012-05-23 00:09:34 +0200307 dev_set_drvdata(dev, NULL);
Kay Sievers1901fb22006-10-07 21:55:55 +0200308
Grant Likelyd1c34142012-03-05 08:47:41 -0700309 if (ret == -EPROBE_DEFER) {
310 /* Driver requested deferred probing */
311 dev_info(dev, "Driver %s requests probe deferral\n", drv->name);
312 driver_deferred_probe_add(dev);
313 } else if (ret != -ENODEV && ret != -ENXIO) {
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700314 /* driver matched but the probe failed */
315 printk(KERN_WARNING
316 "%s: probe of %s failed with error %d\n",
Kay Sievers1e0b2cf2008-10-30 01:36:48 +0100317 drv->name, dev_name(dev), ret);
Wolfram Sangbcbe4f92011-09-20 19:41:17 +0200318 } else {
319 pr_debug("%s: probe of %s rejects match %d\n",
320 drv->name, dev_name(dev), ret);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700321 }
Cornelia Huckc578abb2006-11-27 10:35:10 +0100322 /*
323 * Ignore errors returned by ->probe so that the next driver can try
324 * its luck.
325 */
326 ret = 0;
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700327done:
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700328 atomic_dec(&probe_count);
Andrew Morton735a7ff2006-10-27 11:42:37 -0700329 wake_up(&probe_waitqueue);
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700330 return ret;
331}
332
333/**
334 * driver_probe_done
335 * Determine if the probe sequence is finished or not.
336 *
337 * Should somehow figure out how to use a semaphore, not an atomic variable...
338 */
339int driver_probe_done(void)
340{
Harvey Harrison2b3a3022008-03-04 16:41:05 -0800341 pr_debug("%s: probe_count = %d\n", __func__,
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700342 atomic_read(&probe_count));
343 if (atomic_read(&probe_count))
344 return -EBUSY;
345 return 0;
346}
347
348/**
Arjan van de Ven216773a2009-02-14 01:59:06 +0100349 * wait_for_device_probe
350 * Wait for device probing to be completed.
Arjan van de Ven216773a2009-02-14 01:59:06 +0100351 */
Ming Leib23530e2009-02-21 16:45:07 +0800352void wait_for_device_probe(void)
Arjan van de Ven216773a2009-02-14 01:59:06 +0100353{
354 /* wait for the known devices to complete their probing */
Ming Leib23530e2009-02-21 16:45:07 +0800355 wait_event(probe_waitqueue, atomic_read(&probe_count) == 0);
Arjan van de Ven216773a2009-02-14 01:59:06 +0100356 async_synchronize_full();
Arjan van de Ven216773a2009-02-14 01:59:06 +0100357}
Arjan van de Vend4d52912009-04-21 13:32:54 -0700358EXPORT_SYMBOL_GPL(wait_for_device_probe);
Arjan van de Ven216773a2009-02-14 01:59:06 +0100359
360/**
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700361 * driver_probe_device - attempt to bind device & driver together
362 * @drv: driver to bind a device to
363 * @dev: device to try to bind to the driver
364 *
Ming Lei49b420a2009-01-21 23:27:47 +0800365 * This function returns -ENODEV if the device is not registered,
André Goddard Rosaaf901ca2009-11-14 13:09:05 -0200366 * 1 if the device is bound successfully and 0 otherwise.
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700367 *
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800368 * This function must be called with @dev lock held. When called for a
369 * USB interface, @dev->parent lock must be held as well.
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700370 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800371int driver_probe_device(struct device_driver *drv, struct device *dev)
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700372{
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700373 int ret = 0;
374
Alan Sternf2eaae12006-09-18 16:22:34 -0400375 if (!device_is_registered(dev))
376 return -ENODEV;
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700377
Greg Kroah-Hartman7dc72b22007-11-28 23:49:41 -0800378 pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
Kay Sievers1e0b2cf2008-10-30 01:36:48 +0100379 drv->bus->name, __func__, dev_name(dev), drv->name);
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700380
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +0200381 pm_runtime_barrier(dev);
Cornelia Huck21c7f302007-02-05 16:15:25 -0800382 ret = really_probe(dev, drv);
Ulf Hanssonfa180eb2013-04-10 17:00:48 +0200383 pm_request_idle(dev);
Greg Kroah-Hartmand7792492006-07-18 10:59:59 -0700384
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700385 return ret;
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800386}
387
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800388static int __device_attach(struct device_driver *drv, void *data)
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800389{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800390 struct device *dev = data;
Ming Lei49b420a2009-01-21 23:27:47 +0800391
392 if (!driver_match_device(drv, dev))
393 return 0;
394
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700395 return driver_probe_device(drv, dev);
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800396}
397
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800398/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800399 * device_attach - try to attach device to a driver.
400 * @dev: device.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800401 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800402 * Walk the list of drivers that the bus has and call
403 * driver_probe_device() for each pair. If a compatible
404 * pair is found, break out and return.
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700405 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800406 * Returns 1 if the device was bound to a driver;
Dmitry Torokhov59a3cd72009-05-05 20:38:28 -0700407 * 0 if no matching driver was found;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800408 * -ENODEV if the device is not registered.
Alan Sternbf74ad52005-11-17 16:54:12 -0500409 *
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800410 * When called for a USB interface, @dev->parent lock must be held.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800411 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800412int device_attach(struct device *dev)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800413{
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700414 int ret = 0;
415
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800416 device_lock(dev);
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800417 if (dev->driver) {
Sebastian Ott8497d6a2011-04-12 19:05:37 +0200418 if (klist_node_attached(&dev->p->knode_driver)) {
419 ret = 1;
420 goto out_unlock;
421 }
Andrew Mortonf86db392006-08-14 22:43:20 -0700422 ret = device_bind_driver(dev);
423 if (ret == 0)
424 ret = 1;
Cornelia Huckc6a46692007-02-05 16:15:26 -0800425 else {
426 dev->driver = NULL;
427 ret = 0;
428 }
Cornelia Huck21c7f302007-02-05 16:15:25 -0800429 } else {
Adrian Bunk5adc55d2007-03-27 03:02:51 +0200430 ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach);
Ulf Hanssonfa180eb2013-04-10 17:00:48 +0200431 pm_request_idle(dev);
Cornelia Huck21c7f302007-02-05 16:15:25 -0800432 }
Sebastian Ott8497d6a2011-04-12 19:05:37 +0200433out_unlock:
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800434 device_unlock(dev);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700435 return ret;
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800436}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800437EXPORT_SYMBOL_GPL(device_attach);
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800438
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800439static int __driver_attach(struct device *dev, void *data)
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800440{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800441 struct device_driver *drv = data;
mochel@digitalimplant.org2287c322005-03-24 10:50:24 -0800442
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700443 /*
444 * Lock device and try to bind to it. We drop the error
445 * here and always return 0, because we need to keep trying
446 * to bind to devices and some drivers will return an error
447 * simply if it didn't support the device.
448 *
449 * driver_probe_device() will spit a warning if there
450 * is an error.
451 */
452
Ming Lei49b420a2009-01-21 23:27:47 +0800453 if (!driver_match_device(drv, dev))
Arjan van de Ven6cd49582008-09-14 08:32:06 -0700454 return 0;
455
Alan Sternbf74ad52005-11-17 16:54:12 -0500456 if (dev->parent) /* Needed for USB */
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800457 device_lock(dev->parent);
458 device_lock(dev);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700459 if (!dev->driver)
460 driver_probe_device(drv, dev);
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800461 device_unlock(dev);
Alan Sternbf74ad52005-11-17 16:54:12 -0500462 if (dev->parent)
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800463 device_unlock(dev->parent);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700464
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800465 return 0;
466}
467
468/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800469 * driver_attach - try to bind driver to devices.
470 * @drv: driver.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800471 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800472 * Walk the list of devices that the bus has on it and try to
473 * match the driver with each one. If driver_probe_device()
474 * returns 0 and the @dev->driver is set, we've found a
475 * compatible pair.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800476 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800477int driver_attach(struct device_driver *drv)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800478{
Andrew Mortonf86db392006-08-14 22:43:20 -0700479 return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach);
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800480}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800481EXPORT_SYMBOL_GPL(driver_attach);
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800482
Stefan Richterab71c6f2007-06-17 11:02:12 +0200483/*
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800484 * __device_release_driver() must be called with @dev lock held.
485 * When called for a USB interface, @dev->parent lock must be held as well.
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800486 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800487static void __device_release_driver(struct device *dev)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800488{
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800489 struct device_driver *drv;
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800490
Alan Sternef2c5172007-11-16 11:57:28 -0500491 drv = dev->driver;
Alan Sternc95a6b02005-05-06 15:38:33 -0400492 if (drv) {
Rafael J. Wysockie1866b32011-04-29 00:33:45 +0200493 pm_runtime_get_sync(dev);
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +0200494
Kay Sievers1901fb22006-10-07 21:55:55 +0200495 driver_sysfs_remove(dev);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700496
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000497 if (dev->bus)
Greg Kroah-Hartmanc6f7e722007-11-01 19:41:16 -0700498 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
Benjamin Herrenschmidt116af372006-10-25 13:44:59 +1000499 BUS_NOTIFY_UNBIND_DRIVER,
500 dev);
501
Ulf Hanssonfa180eb2013-04-10 17:00:48 +0200502 pm_runtime_put(dev);
Rafael J. Wysockie1866b32011-04-29 00:33:45 +0200503
Alan Stern0f836ca2006-03-31 11:52:25 -0500504 if (dev->bus && dev->bus->remove)
Russell King594c8282006-01-05 14:29:51 +0000505 dev->bus->remove(dev);
506 else if (drv->remove)
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700507 drv->remove(dev);
Tejun Heo9ac78492007-01-20 16:00:26 +0900508 devres_release_all(dev);
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700509 dev->driver = NULL;
Hans de Goede0998d062012-05-23 00:09:34 +0200510 dev_set_drvdata(dev, NULL);
Greg Kroah-Hartman8940b4f2008-12-16 12:25:49 -0800511 klist_remove(&dev->p->knode_driver);
Joerg Roedel309b7d62009-04-24 14:57:00 +0200512 if (dev->bus)
513 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
514 BUS_NOTIFY_UNBOUND_DRIVER,
515 dev);
Rafael J. Wysocki5e928f72009-08-18 23:38:32 +0200516
Patrick Mochel0d3e5a22005-04-05 23:46:33 -0700517 }
Alan Sternc95a6b02005-05-06 15:38:33 -0400518}
519
Stefan Richterab71c6f2007-06-17 11:02:12 +0200520/**
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800521 * device_release_driver - manually detach device from driver.
522 * @dev: device.
Stefan Richterab71c6f2007-06-17 11:02:12 +0200523 *
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800524 * Manually detach device from driver.
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800525 * When called for a USB interface, @dev->parent lock must be held.
Stefan Richterab71c6f2007-06-17 11:02:12 +0200526 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800527void device_release_driver(struct device *dev)
Alan Sternc95a6b02005-05-06 15:38:33 -0400528{
529 /*
530 * If anyone calls device_release_driver() recursively from
531 * within their ->remove callback for the same device, they
532 * will deadlock right here.
533 */
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800534 device_lock(dev);
Alan Sternc95a6b02005-05-06 15:38:33 -0400535 __device_release_driver(dev);
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800536 device_unlock(dev);
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800537}
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800538EXPORT_SYMBOL_GPL(device_release_driver);
mochel@digitalimplant.org94e7b1c52005-03-21 12:25:36 -0800539
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800540/**
541 * driver_detach - detach driver from all devices it controls.
542 * @drv: driver.
543 */
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800544void driver_detach(struct device_driver *drv)
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800545{
Greg Kroah-Hartman8940b4f2008-12-16 12:25:49 -0800546 struct device_private *dev_prv;
Greg Kroah-Hartman4a3ad202008-01-24 22:50:12 -0800547 struct device *dev;
Alan Sternc95a6b02005-05-06 15:38:33 -0400548
549 for (;;) {
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800550 spin_lock(&drv->p->klist_devices.k_lock);
551 if (list_empty(&drv->p->klist_devices.k_list)) {
552 spin_unlock(&drv->p->klist_devices.k_lock);
Alan Sternc95a6b02005-05-06 15:38:33 -0400553 break;
554 }
Greg Kroah-Hartman8940b4f2008-12-16 12:25:49 -0800555 dev_prv = list_entry(drv->p->klist_devices.k_list.prev,
556 struct device_private,
557 knode_driver.n_node);
558 dev = dev_prv->device;
Alan Sternc95a6b02005-05-06 15:38:33 -0400559 get_device(dev);
Greg Kroah-Hartmane5dd1272007-11-28 15:59:15 -0800560 spin_unlock(&drv->p->klist_devices.k_lock);
Alan Sternc95a6b02005-05-06 15:38:33 -0400561
Alan Sternbf74ad52005-11-17 16:54:12 -0500562 if (dev->parent) /* Needed for USB */
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800563 device_lock(dev->parent);
564 device_lock(dev);
Alan Sternc95a6b02005-05-06 15:38:33 -0400565 if (dev->driver == drv)
566 __device_release_driver(dev);
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800567 device_unlock(dev);
Alan Sternbf74ad52005-11-17 16:54:12 -0500568 if (dev->parent)
Greg Kroah-Hartman8e9394c2010-02-17 10:57:05 -0800569 device_unlock(dev->parent);
Alan Sternc95a6b02005-05-06 15:38:33 -0400570 put_device(dev);
571 }
mochel@digitalimplant.org07e4a3e2005-03-21 10:52:54 -0800572}
Greg Kroah-Hartmanb4028432009-05-11 14:16:57 -0700573
574/*
575 * These exports can't be _GPL due to .h files using this within them, and it
576 * might break something that was previously working...
577 */
578void *dev_get_drvdata(const struct device *dev)
579{
580 if (dev && dev->p)
581 return dev->p->driver_data;
582 return NULL;
583}
584EXPORT_SYMBOL(dev_get_drvdata);
585
Uwe Kleine-Königc8705082011-04-20 09:44:46 +0200586int dev_set_drvdata(struct device *dev, void *data)
Greg Kroah-Hartmanb4028432009-05-11 14:16:57 -0700587{
588 int error;
589
Greg Kroah-Hartmanb4028432009-05-11 14:16:57 -0700590 if (!dev->p) {
591 error = device_private_init(dev);
592 if (error)
Uwe Kleine-Königc8705082011-04-20 09:44:46 +0200593 return error;
Greg Kroah-Hartmanb4028432009-05-11 14:16:57 -0700594 }
595 dev->p->driver_data = data;
Uwe Kleine-Königc8705082011-04-20 09:44:46 +0200596 return 0;
Greg Kroah-Hartmanb4028432009-05-11 14:16:57 -0700597}
598EXPORT_SYMBOL(dev_set_drvdata);