mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 1 | /* |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 2 | * drivers/base/dd.c - The core device/driver interactions. |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 3 | * |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 4 | * 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.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 7 | * |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 8 | * 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.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 11 | * |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 12 | * Copyright (c) 2002-5 Patrick Mochel |
| 13 | * Copyright (c) 2002-3 Open Source Development Labs |
Greg Kroah-Hartman | b402843 | 2009-05-11 14:16:57 -0700 | [diff] [blame] | 14 | * Copyright (c) 2007-2009 Greg Kroah-Hartman <gregkh@suse.de> |
| 15 | * Copyright (c) 2007-2009 Novell Inc. |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 16 | * |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 17 | * This file is released under the GPLv2 |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 18 | */ |
| 19 | |
| 20 | #include <linux/device.h> |
Arjan van de Ven | 216773a | 2009-02-14 01:59:06 +0100 | [diff] [blame] | 21 | #include <linux/delay.h> |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 22 | #include <linux/module.h> |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 23 | #include <linux/kthread.h> |
Andrew Morton | 735a7ff | 2006-10-27 11:42:37 -0700 | [diff] [blame] | 24 | #include <linux/wait.h> |
Arjan van de Ven | 216773a | 2009-02-14 01:59:06 +0100 | [diff] [blame] | 25 | #include <linux/async.h> |
Rafael J. Wysocki | 5e928f7 | 2009-08-18 23:38:32 +0200 | [diff] [blame] | 26 | #include <linux/pm_runtime.h> |
Linus Walleij | ab78029 | 2013-01-22 10:56:14 -0700 | [diff] [blame] | 27 | #include <linux/pinctrl/devinfo.h> |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 28 | |
| 29 | #include "base.h" |
| 30 | #include "power/power.h" |
| 31 | |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 32 | /* |
| 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-Hartman | ef8a3fd | 2012-03-08 12:17:22 -0800 | [diff] [blame] | 49 | * of the (struct device*)->p->deferred_probe pointers are manipulated |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 50 | */ |
| 51 | static DEFINE_MUTEX(deferred_probe_mutex); |
| 52 | static LIST_HEAD(deferred_probe_pending_list); |
| 53 | static LIST_HEAD(deferred_probe_active_list); |
| 54 | static struct workqueue_struct *deferred_wq; |
Grant Likely | 58b116b | 2014-04-29 12:05:22 +0100 | [diff] [blame] | 55 | static atomic_t deferred_trigger_count = ATOMIC_INIT(0); |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 56 | |
Thierry Reding | 4157533 | 2014-08-08 15:56:36 +0200 | [diff] [blame] | 57 | /* |
Strashko, Grygorii | 013c074 | 2015-11-10 11:42:34 +0200 | [diff] [blame] | 58 | * In some cases, like suspend to RAM or hibernation, It might be reasonable |
| 59 | * to prohibit probing of devices as it could be unsafe. |
| 60 | * Once defer_all_probes is true all drivers probes will be forcibly deferred. |
| 61 | */ |
| 62 | static bool defer_all_probes; |
| 63 | |
| 64 | /* |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 65 | * deferred_probe_work_func() - Retry probing devices in the active list. |
| 66 | */ |
| 67 | static void deferred_probe_work_func(struct work_struct *work) |
| 68 | { |
| 69 | struct device *dev; |
Greg Kroah-Hartman | ef8a3fd | 2012-03-08 12:17:22 -0800 | [diff] [blame] | 70 | struct device_private *private; |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 71 | /* |
| 72 | * This block processes every device in the deferred 'active' list. |
| 73 | * Each device is removed from the active list and passed to |
| 74 | * bus_probe_device() to re-attempt the probe. The loop continues |
| 75 | * until every device in the active list is removed and retried. |
| 76 | * |
| 77 | * Note: Once the device is removed from the list and the mutex is |
| 78 | * released, it is possible for the device get freed by another thread |
| 79 | * and cause a illegal pointer dereference. This code uses |
| 80 | * get/put_device() to ensure the device structure cannot disappear |
| 81 | * from under our feet. |
| 82 | */ |
| 83 | mutex_lock(&deferred_probe_mutex); |
| 84 | while (!list_empty(&deferred_probe_active_list)) { |
Greg Kroah-Hartman | ef8a3fd | 2012-03-08 12:17:22 -0800 | [diff] [blame] | 85 | private = list_first_entry(&deferred_probe_active_list, |
| 86 | typeof(*dev->p), deferred_probe); |
| 87 | dev = private->device; |
| 88 | list_del_init(&private->deferred_probe); |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 89 | |
| 90 | get_device(dev); |
| 91 | |
Greg Kroah-Hartman | 8b0372a | 2012-03-08 12:20:37 -0800 | [diff] [blame] | 92 | /* |
| 93 | * Drop the mutex while probing each device; the probe path may |
| 94 | * manipulate the deferred list |
| 95 | */ |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 96 | mutex_unlock(&deferred_probe_mutex); |
Mark Brown | 8153584 | 2012-07-05 14:04:44 +0100 | [diff] [blame] | 97 | |
| 98 | /* |
| 99 | * Force the device to the end of the dpm_list since |
| 100 | * the PM code assumes that the order we add things to |
| 101 | * the list is a good order for suspend but deferred |
| 102 | * probe makes that very unsafe. |
| 103 | */ |
| 104 | device_pm_lock(); |
| 105 | device_pm_move_last(dev); |
| 106 | device_pm_unlock(); |
| 107 | |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 108 | dev_dbg(dev, "Retrying from deferred list\n"); |
| 109 | bus_probe_device(dev); |
Mark Brown | 8153584 | 2012-07-05 14:04:44 +0100 | [diff] [blame] | 110 | |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 111 | mutex_lock(&deferred_probe_mutex); |
| 112 | |
| 113 | put_device(dev); |
| 114 | } |
| 115 | mutex_unlock(&deferred_probe_mutex); |
| 116 | } |
| 117 | static DECLARE_WORK(deferred_probe_work, deferred_probe_work_func); |
| 118 | |
| 119 | static void driver_deferred_probe_add(struct device *dev) |
| 120 | { |
| 121 | mutex_lock(&deferred_probe_mutex); |
Greg Kroah-Hartman | ef8a3fd | 2012-03-08 12:17:22 -0800 | [diff] [blame] | 122 | if (list_empty(&dev->p->deferred_probe)) { |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 123 | dev_dbg(dev, "Added to deferred list\n"); |
Kuninori Morimoto | 1d29cfa5 | 2012-05-29 18:46:06 -0700 | [diff] [blame] | 124 | list_add_tail(&dev->p->deferred_probe, &deferred_probe_pending_list); |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 125 | } |
| 126 | mutex_unlock(&deferred_probe_mutex); |
| 127 | } |
| 128 | |
| 129 | void driver_deferred_probe_del(struct device *dev) |
| 130 | { |
| 131 | mutex_lock(&deferred_probe_mutex); |
Greg Kroah-Hartman | ef8a3fd | 2012-03-08 12:17:22 -0800 | [diff] [blame] | 132 | if (!list_empty(&dev->p->deferred_probe)) { |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 133 | dev_dbg(dev, "Removed from deferred list\n"); |
Greg Kroah-Hartman | ef8a3fd | 2012-03-08 12:17:22 -0800 | [diff] [blame] | 134 | list_del_init(&dev->p->deferred_probe); |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 135 | } |
| 136 | mutex_unlock(&deferred_probe_mutex); |
| 137 | } |
| 138 | |
| 139 | static bool driver_deferred_probe_enable = false; |
| 140 | /** |
| 141 | * driver_deferred_probe_trigger() - Kick off re-probing deferred devices |
| 142 | * |
| 143 | * This functions moves all devices from the pending list to the active |
| 144 | * list and schedules the deferred probe workqueue to process them. It |
| 145 | * should be called anytime a driver is successfully bound to a device. |
Grant Likely | 58b116b | 2014-04-29 12:05:22 +0100 | [diff] [blame] | 146 | * |
| 147 | * Note, there is a race condition in multi-threaded probe. In the case where |
| 148 | * more than one device is probing at the same time, it is possible for one |
| 149 | * probe to complete successfully while another is about to defer. If the second |
| 150 | * depends on the first, then it will get put on the pending list after the |
Shailendra Verma | 9ba8af6 | 2015-05-25 23:46:11 +0530 | [diff] [blame] | 151 | * trigger event has already occurred and will be stuck there. |
Grant Likely | 58b116b | 2014-04-29 12:05:22 +0100 | [diff] [blame] | 152 | * |
| 153 | * The atomic 'deferred_trigger_count' is used to determine if a successful |
| 154 | * trigger has occurred in the midst of probing a driver. If the trigger count |
| 155 | * changes in the midst of a probe, then deferred processing should be triggered |
| 156 | * again. |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 157 | */ |
| 158 | static void driver_deferred_probe_trigger(void) |
| 159 | { |
| 160 | if (!driver_deferred_probe_enable) |
| 161 | return; |
| 162 | |
Greg Kroah-Hartman | 8b0372a | 2012-03-08 12:20:37 -0800 | [diff] [blame] | 163 | /* |
| 164 | * A successful probe means that all the devices in the pending list |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 165 | * should be triggered to be reprobed. Move all the deferred devices |
Greg Kroah-Hartman | 8b0372a | 2012-03-08 12:20:37 -0800 | [diff] [blame] | 166 | * into the active list so they can be retried by the workqueue |
| 167 | */ |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 168 | mutex_lock(&deferred_probe_mutex); |
Grant Likely | 58b116b | 2014-04-29 12:05:22 +0100 | [diff] [blame] | 169 | atomic_inc(&deferred_trigger_count); |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 170 | list_splice_tail_init(&deferred_probe_pending_list, |
| 171 | &deferred_probe_active_list); |
| 172 | mutex_unlock(&deferred_probe_mutex); |
| 173 | |
Greg Kroah-Hartman | 8b0372a | 2012-03-08 12:20:37 -0800 | [diff] [blame] | 174 | /* |
| 175 | * Kick the re-probe thread. It may already be scheduled, but it is |
| 176 | * safe to kick it again. |
| 177 | */ |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 178 | queue_work(deferred_wq, &deferred_probe_work); |
| 179 | } |
| 180 | |
| 181 | /** |
Strashko, Grygorii | 013c074 | 2015-11-10 11:42:34 +0200 | [diff] [blame] | 182 | * device_block_probing() - Block/defere device's probes |
| 183 | * |
| 184 | * It will disable probing of devices and defer their probes instead. |
| 185 | */ |
| 186 | void device_block_probing(void) |
| 187 | { |
| 188 | defer_all_probes = true; |
| 189 | /* sync with probes to avoid races. */ |
| 190 | wait_for_device_probe(); |
| 191 | } |
| 192 | |
| 193 | /** |
| 194 | * device_unblock_probing() - Unblock/enable device's probes |
| 195 | * |
| 196 | * It will restore normal behavior and trigger re-probing of deferred |
| 197 | * devices. |
| 198 | */ |
| 199 | void device_unblock_probing(void) |
| 200 | { |
| 201 | defer_all_probes = false; |
| 202 | driver_deferred_probe_trigger(); |
| 203 | } |
| 204 | |
| 205 | /** |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 206 | * deferred_probe_initcall() - Enable probing of deferred devices |
| 207 | * |
| 208 | * We don't want to get in the way when the bulk of drivers are getting probed. |
| 209 | * Instead, this initcall makes sure that deferred probing is delayed until |
| 210 | * late_initcall time. |
| 211 | */ |
| 212 | static int deferred_probe_initcall(void) |
| 213 | { |
| 214 | deferred_wq = create_singlethread_workqueue("deferwq"); |
| 215 | if (WARN_ON(!deferred_wq)) |
| 216 | return -ENOMEM; |
| 217 | |
| 218 | driver_deferred_probe_enable = true; |
| 219 | driver_deferred_probe_trigger(); |
Grant Likely | d72cca1 | 2013-02-14 18:14:27 +0000 | [diff] [blame] | 220 | /* Sort as many dependencies as possible before exiting initcalls */ |
| 221 | flush_workqueue(deferred_wq); |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 222 | return 0; |
| 223 | } |
| 224 | late_initcall(deferred_probe_initcall); |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 225 | |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 226 | static void driver_bound(struct device *dev) |
| 227 | { |
Greg Kroah-Hartman | 8940b4f | 2008-12-16 12:25:49 -0800 | [diff] [blame] | 228 | if (klist_node_attached(&dev->p->knode_driver)) { |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 229 | printk(KERN_WARNING "%s: device %s already bound\n", |
Harvey Harrison | 2b3a302 | 2008-03-04 16:41:05 -0800 | [diff] [blame] | 230 | __func__, kobject_name(&dev->kobj)); |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 231 | return; |
| 232 | } |
| 233 | |
Frank Rowand | 94f8cc0 | 2014-04-16 17:12:30 -0700 | [diff] [blame] | 234 | pr_debug("driver: '%s': %s: bound to device '%s'\n", dev->driver->name, |
| 235 | __func__, dev_name(dev)); |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 236 | |
Stefani Seibold | fbb88fa | 2010-03-06 17:50:14 +0100 | [diff] [blame] | 237 | klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices); |
| 238 | |
Greg Kroah-Hartman | 8b0372a | 2012-03-08 12:20:37 -0800 | [diff] [blame] | 239 | /* |
| 240 | * Make sure the device is no longer in one of the deferred lists and |
| 241 | * kick off retrying all pending devices |
| 242 | */ |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 243 | driver_deferred_probe_del(dev); |
| 244 | driver_deferred_probe_trigger(); |
| 245 | |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 246 | if (dev->bus) |
Greg Kroah-Hartman | c6f7e72 | 2007-11-01 19:41:16 -0700 | [diff] [blame] | 247 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 248 | BUS_NOTIFY_BOUND_DRIVER, dev); |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 249 | } |
| 250 | |
| 251 | static int driver_sysfs_add(struct device *dev) |
| 252 | { |
| 253 | int ret; |
| 254 | |
Magnus Damm | 45daef0 | 2010-07-23 19:56:18 +0900 | [diff] [blame] | 255 | if (dev->bus) |
| 256 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
| 257 | BUS_NOTIFY_BIND_DRIVER, dev); |
| 258 | |
Greg Kroah-Hartman | e5dd127 | 2007-11-28 15:59:15 -0800 | [diff] [blame] | 259 | ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj, |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 260 | kobject_name(&dev->kobj)); |
| 261 | if (ret == 0) { |
Greg Kroah-Hartman | e5dd127 | 2007-11-28 15:59:15 -0800 | [diff] [blame] | 262 | ret = sysfs_create_link(&dev->kobj, &dev->driver->p->kobj, |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 263 | "driver"); |
| 264 | if (ret) |
Greg Kroah-Hartman | e5dd127 | 2007-11-28 15:59:15 -0800 | [diff] [blame] | 265 | sysfs_remove_link(&dev->driver->p->kobj, |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 266 | kobject_name(&dev->kobj)); |
| 267 | } |
| 268 | return ret; |
| 269 | } |
| 270 | |
| 271 | static void driver_sysfs_remove(struct device *dev) |
| 272 | { |
| 273 | struct device_driver *drv = dev->driver; |
| 274 | |
| 275 | if (drv) { |
Greg Kroah-Hartman | e5dd127 | 2007-11-28 15:59:15 -0800 | [diff] [blame] | 276 | sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj)); |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 277 | sysfs_remove_link(&dev->kobj, "driver"); |
| 278 | } |
| 279 | } |
| 280 | |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 281 | /** |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 282 | * device_bind_driver - bind a driver to one device. |
| 283 | * @dev: device. |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 284 | * |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 285 | * Allow manual attachment of a driver to a device. |
| 286 | * Caller must have already set @dev->driver. |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 287 | * |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 288 | * Note that this does not modify the bus reference count |
| 289 | * nor take the bus's rwsem. Please verify those are accounted |
| 290 | * for before calling this. (It is ok to call with no other effort |
| 291 | * from a driver's probe() method.) |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 292 | * |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 293 | * This function must be called with the device lock held. |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 294 | */ |
Andrew Morton | f86db39 | 2006-08-14 22:43:20 -0700 | [diff] [blame] | 295 | int device_bind_driver(struct device *dev) |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 296 | { |
Cornelia Huck | cb986b7 | 2006-11-27 10:35:12 +0100 | [diff] [blame] | 297 | int ret; |
| 298 | |
| 299 | ret = driver_sysfs_add(dev); |
| 300 | if (!ret) |
| 301 | driver_bound(dev); |
Andy Shevchenko | 14b6257 | 2015-12-04 23:49:17 +0200 | [diff] [blame] | 302 | else if (dev->bus) |
| 303 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
| 304 | BUS_NOTIFY_DRIVER_NOT_BOUND, dev); |
Cornelia Huck | cb986b7 | 2006-11-27 10:35:12 +0100 | [diff] [blame] | 305 | return ret; |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 306 | } |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 307 | EXPORT_SYMBOL_GPL(device_bind_driver); |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 308 | |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 309 | static atomic_t probe_count = ATOMIC_INIT(0); |
Andrew Morton | 735a7ff | 2006-10-27 11:42:37 -0700 | [diff] [blame] | 310 | static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue); |
| 311 | |
Cornelia Huck | 21c7f30 | 2007-02-05 16:15:25 -0800 | [diff] [blame] | 312 | static int really_probe(struct device *dev, struct device_driver *drv) |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 313 | { |
Strashko, Grygorii | 013c074 | 2015-11-10 11:42:34 +0200 | [diff] [blame] | 314 | int ret = -EPROBE_DEFER; |
Grant Likely | 58b116b | 2014-04-29 12:05:22 +0100 | [diff] [blame] | 315 | int local_trigger_count = atomic_read(&deferred_trigger_count); |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 316 | |
Strashko, Grygorii | 013c074 | 2015-11-10 11:42:34 +0200 | [diff] [blame] | 317 | if (defer_all_probes) { |
| 318 | /* |
| 319 | * Value of defer_all_probes can be set only by |
| 320 | * device_defer_all_probes_enable() which, in turn, will call |
| 321 | * wait_for_device_probe() right after that to avoid any races. |
| 322 | */ |
| 323 | dev_dbg(dev, "Driver %s force probe deferral\n", drv->name); |
| 324 | driver_deferred_probe_add(dev); |
| 325 | return ret; |
| 326 | } |
| 327 | |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 328 | atomic_inc(&probe_count); |
Greg Kroah-Hartman | 7dc72b2 | 2007-11-28 23:49:41 -0800 | [diff] [blame] | 329 | pr_debug("bus: '%s': %s: probing driver %s with device %s\n", |
Kay Sievers | 1e0b2cf | 2008-10-30 01:36:48 +0100 | [diff] [blame] | 330 | drv->bus->name, __func__, drv->name, dev_name(dev)); |
Tejun Heo | 9ac7849 | 2007-01-20 16:00:26 +0900 | [diff] [blame] | 331 | WARN_ON(!list_empty(&dev->devres_head)); |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 332 | |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 333 | dev->driver = drv; |
Linus Walleij | ab78029 | 2013-01-22 10:56:14 -0700 | [diff] [blame] | 334 | |
| 335 | /* If using pinctrl, bind pins now before probing */ |
| 336 | ret = pinctrl_bind_pins(dev); |
| 337 | if (ret) |
Andy Shevchenko | 14b6257 | 2015-12-04 23:49:17 +0200 | [diff] [blame] | 338 | goto pinctrl_bind_failed; |
Linus Walleij | ab78029 | 2013-01-22 10:56:14 -0700 | [diff] [blame] | 339 | |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 340 | if (driver_sysfs_add(dev)) { |
| 341 | printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n", |
Kay Sievers | 1e0b2cf | 2008-10-30 01:36:48 +0100 | [diff] [blame] | 342 | __func__, dev_name(dev)); |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 343 | goto probe_failed; |
| 344 | } |
| 345 | |
Rafael J. Wysocki | e90d553 | 2015-03-20 13:59:27 +0100 | [diff] [blame] | 346 | if (dev->pm_domain && dev->pm_domain->activate) { |
| 347 | ret = dev->pm_domain->activate(dev); |
| 348 | if (ret) |
| 349 | goto probe_failed; |
| 350 | } |
| 351 | |
Grygorii Strashko | 52cdbdd | 2015-07-27 20:43:01 +0300 | [diff] [blame] | 352 | /* |
| 353 | * Ensure devices are listed in devices_kset in correct order |
| 354 | * It's important to move Dev to the end of devices_kset before |
| 355 | * calling .probe, because it could be recursive and parent Dev |
| 356 | * should always go first |
| 357 | */ |
| 358 | devices_kset_move_last(dev); |
| 359 | |
Russell King | 594c828 | 2006-01-05 14:29:51 +0000 | [diff] [blame] | 360 | if (dev->bus->probe) { |
| 361 | ret = dev->bus->probe(dev); |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 362 | if (ret) |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 363 | goto probe_failed; |
Russell King | 594c828 | 2006-01-05 14:29:51 +0000 | [diff] [blame] | 364 | } else if (drv->probe) { |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 365 | ret = drv->probe(dev); |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 366 | if (ret) |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 367 | goto probe_failed; |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 368 | } |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 369 | |
Douglas Anderson | ef0eebc | 2015-10-20 21:15:06 -0700 | [diff] [blame] | 370 | pinctrl_init_done(dev); |
| 371 | |
Rafael J. Wysocki | e90d553 | 2015-03-20 13:59:27 +0100 | [diff] [blame] | 372 | if (dev->pm_domain && dev->pm_domain->sync) |
| 373 | dev->pm_domain->sync(dev); |
| 374 | |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 375 | driver_bound(dev); |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 376 | ret = 1; |
Greg Kroah-Hartman | 7dc72b2 | 2007-11-28 23:49:41 -0800 | [diff] [blame] | 377 | pr_debug("bus: '%s': %s: bound device %s to driver %s\n", |
Kay Sievers | 1e0b2cf | 2008-10-30 01:36:48 +0100 | [diff] [blame] | 378 | drv->bus->name, __func__, dev_name(dev), drv->name); |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 379 | goto done; |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 380 | |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 381 | probe_failed: |
Andy Shevchenko | 14b6257 | 2015-12-04 23:49:17 +0200 | [diff] [blame] | 382 | if (dev->bus) |
| 383 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
| 384 | BUS_NOTIFY_DRIVER_NOT_BOUND, dev); |
| 385 | pinctrl_bind_failed: |
Tejun Heo | 9ac7849 | 2007-01-20 16:00:26 +0900 | [diff] [blame] | 386 | devres_release_all(dev); |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 387 | driver_sysfs_remove(dev); |
| 388 | dev->driver = NULL; |
Hans de Goede | 0998d06 | 2012-05-23 00:09:34 +0200 | [diff] [blame] | 389 | dev_set_drvdata(dev, NULL); |
Rafael J. Wysocki | e90d553 | 2015-03-20 13:59:27 +0100 | [diff] [blame] | 390 | if (dev->pm_domain && dev->pm_domain->dismiss) |
| 391 | dev->pm_domain->dismiss(dev); |
Ulf Hansson | 5de85b9 | 2015-11-18 11:48:39 +0100 | [diff] [blame] | 392 | pm_runtime_reinit(dev); |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 393 | |
Sergei Shtylyov | bb2b407 | 2015-01-17 22:14:41 +0300 | [diff] [blame] | 394 | switch (ret) { |
| 395 | case -EPROBE_DEFER: |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 396 | /* Driver requested deferred probing */ |
Mark Brown | 13fcffb | 2015-03-10 11:55:49 +0000 | [diff] [blame] | 397 | dev_dbg(dev, "Driver %s requests probe deferral\n", drv->name); |
Grant Likely | d1c3414 | 2012-03-05 08:47:41 -0700 | [diff] [blame] | 398 | driver_deferred_probe_add(dev); |
Grant Likely | 58b116b | 2014-04-29 12:05:22 +0100 | [diff] [blame] | 399 | /* Did a trigger occur while probing? Need to re-trigger if yes */ |
| 400 | if (local_trigger_count != atomic_read(&deferred_trigger_count)) |
| 401 | driver_deferred_probe_trigger(); |
Sergei Shtylyov | bb2b407 | 2015-01-17 22:14:41 +0300 | [diff] [blame] | 402 | break; |
| 403 | case -ENODEV: |
| 404 | case -ENXIO: |
| 405 | pr_debug("%s: probe of %s rejects match %d\n", |
| 406 | drv->name, dev_name(dev), ret); |
| 407 | break; |
| 408 | default: |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 409 | /* driver matched but the probe failed */ |
| 410 | printk(KERN_WARNING |
| 411 | "%s: probe of %s failed with error %d\n", |
Kay Sievers | 1e0b2cf | 2008-10-30 01:36:48 +0100 | [diff] [blame] | 412 | drv->name, dev_name(dev), ret); |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 413 | } |
Cornelia Huck | c578abb | 2006-11-27 10:35:10 +0100 | [diff] [blame] | 414 | /* |
| 415 | * Ignore errors returned by ->probe so that the next driver can try |
| 416 | * its luck. |
| 417 | */ |
| 418 | ret = 0; |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 419 | done: |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 420 | atomic_dec(&probe_count); |
Andrew Morton | 735a7ff | 2006-10-27 11:42:37 -0700 | [diff] [blame] | 421 | wake_up(&probe_waitqueue); |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 422 | return ret; |
| 423 | } |
| 424 | |
| 425 | /** |
| 426 | * driver_probe_done |
| 427 | * Determine if the probe sequence is finished or not. |
| 428 | * |
| 429 | * Should somehow figure out how to use a semaphore, not an atomic variable... |
| 430 | */ |
| 431 | int driver_probe_done(void) |
| 432 | { |
Harvey Harrison | 2b3a302 | 2008-03-04 16:41:05 -0800 | [diff] [blame] | 433 | pr_debug("%s: probe_count = %d\n", __func__, |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 434 | atomic_read(&probe_count)); |
| 435 | if (atomic_read(&probe_count)) |
| 436 | return -EBUSY; |
| 437 | return 0; |
| 438 | } |
| 439 | |
| 440 | /** |
Arjan van de Ven | 216773a | 2009-02-14 01:59:06 +0100 | [diff] [blame] | 441 | * wait_for_device_probe |
| 442 | * Wait for device probing to be completed. |
Arjan van de Ven | 216773a | 2009-02-14 01:59:06 +0100 | [diff] [blame] | 443 | */ |
Ming Lei | b23530e | 2009-02-21 16:45:07 +0800 | [diff] [blame] | 444 | void wait_for_device_probe(void) |
Arjan van de Ven | 216773a | 2009-02-14 01:59:06 +0100 | [diff] [blame] | 445 | { |
Strashko, Grygorii | 013c074 | 2015-11-10 11:42:34 +0200 | [diff] [blame] | 446 | /* wait for the deferred probe workqueue to finish */ |
| 447 | if (driver_deferred_probe_enable) |
| 448 | flush_workqueue(deferred_wq); |
| 449 | |
Arjan van de Ven | 216773a | 2009-02-14 01:59:06 +0100 | [diff] [blame] | 450 | /* wait for the known devices to complete their probing */ |
Ming Lei | b23530e | 2009-02-21 16:45:07 +0800 | [diff] [blame] | 451 | wait_event(probe_waitqueue, atomic_read(&probe_count) == 0); |
Arjan van de Ven | 216773a | 2009-02-14 01:59:06 +0100 | [diff] [blame] | 452 | async_synchronize_full(); |
Arjan van de Ven | 216773a | 2009-02-14 01:59:06 +0100 | [diff] [blame] | 453 | } |
Arjan van de Ven | d4d5291 | 2009-04-21 13:32:54 -0700 | [diff] [blame] | 454 | EXPORT_SYMBOL_GPL(wait_for_device_probe); |
Arjan van de Ven | 216773a | 2009-02-14 01:59:06 +0100 | [diff] [blame] | 455 | |
| 456 | /** |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 457 | * driver_probe_device - attempt to bind device & driver together |
| 458 | * @drv: driver to bind a device to |
| 459 | * @dev: device to try to bind to the driver |
| 460 | * |
Ming Lei | 49b420a | 2009-01-21 23:27:47 +0800 | [diff] [blame] | 461 | * This function returns -ENODEV if the device is not registered, |
André Goddard Rosa | af901ca | 2009-11-14 13:09:05 -0200 | [diff] [blame] | 462 | * 1 if the device is bound successfully and 0 otherwise. |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 463 | * |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 464 | * This function must be called with @dev lock held. When called for a |
| 465 | * USB interface, @dev->parent lock must be held as well. |
Rafael J. Wysocki | ddef08d | 2015-07-27 18:03:58 +0300 | [diff] [blame] | 466 | * |
| 467 | * If the device has a parent, runtime-resume the parent before driver probing. |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 468 | */ |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 469 | int driver_probe_device(struct device_driver *drv, struct device *dev) |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 470 | { |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 471 | int ret = 0; |
| 472 | |
Alan Stern | f2eaae1 | 2006-09-18 16:22:34 -0400 | [diff] [blame] | 473 | if (!device_is_registered(dev)) |
| 474 | return -ENODEV; |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 475 | |
Greg Kroah-Hartman | 7dc72b2 | 2007-11-28 23:49:41 -0800 | [diff] [blame] | 476 | pr_debug("bus: '%s': %s: matched device %s with driver %s\n", |
Kay Sievers | 1e0b2cf | 2008-10-30 01:36:48 +0100 | [diff] [blame] | 477 | drv->bus->name, __func__, dev_name(dev), drv->name); |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 478 | |
Rafael J. Wysocki | ddef08d | 2015-07-27 18:03:58 +0300 | [diff] [blame] | 479 | if (dev->parent) |
| 480 | pm_runtime_get_sync(dev->parent); |
| 481 | |
Rafael J. Wysocki | 5e928f7 | 2009-08-18 23:38:32 +0200 | [diff] [blame] | 482 | pm_runtime_barrier(dev); |
Cornelia Huck | 21c7f30 | 2007-02-05 16:15:25 -0800 | [diff] [blame] | 483 | ret = really_probe(dev, drv); |
Ulf Hansson | fa180eb | 2013-04-10 17:00:48 +0200 | [diff] [blame] | 484 | pm_request_idle(dev); |
Greg Kroah-Hartman | d779249 | 2006-07-18 10:59:59 -0700 | [diff] [blame] | 485 | |
Rafael J. Wysocki | ddef08d | 2015-07-27 18:03:58 +0300 | [diff] [blame] | 486 | if (dev->parent) |
| 487 | pm_runtime_put(dev->parent); |
| 488 | |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 489 | return ret; |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 490 | } |
| 491 | |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 492 | bool driver_allows_async_probing(struct device_driver *drv) |
mochel@digitalimplant.org | 2287c32 | 2005-03-24 10:50:24 -0800 | [diff] [blame] | 493 | { |
Luis R. Rodriguez | d173a13 | 2015-03-30 16:20:06 -0700 | [diff] [blame] | 494 | switch (drv->probe_type) { |
| 495 | case PROBE_PREFER_ASYNCHRONOUS: |
Luis R. Rodriguez | f2411da | 2015-03-30 16:20:05 -0700 | [diff] [blame] | 496 | return true; |
| 497 | |
Luis R. Rodriguez | d173a13 | 2015-03-30 16:20:06 -0700 | [diff] [blame] | 498 | case PROBE_FORCE_SYNCHRONOUS: |
| 499 | return false; |
Luis R. Rodriguez | f2411da | 2015-03-30 16:20:05 -0700 | [diff] [blame] | 500 | |
Luis R. Rodriguez | d173a13 | 2015-03-30 16:20:06 -0700 | [diff] [blame] | 501 | default: |
Dmitry Torokhov | 80c6e14 | 2015-05-21 15:49:37 -0700 | [diff] [blame] | 502 | if (module_requested_async_probing(drv->owner)) |
Luis R. Rodriguez | d173a13 | 2015-03-30 16:20:06 -0700 | [diff] [blame] | 503 | return true; |
| 504 | |
| 505 | return false; |
| 506 | } |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 507 | } |
| 508 | |
| 509 | struct device_attach_data { |
| 510 | struct device *dev; |
| 511 | |
| 512 | /* |
| 513 | * Indicates whether we are are considering asynchronous probing or |
| 514 | * not. Only initial binding after device or driver registration |
| 515 | * (including deferral processing) may be done asynchronously, the |
| 516 | * rest is always synchronous, as we expect it is being done by |
| 517 | * request from userspace. |
| 518 | */ |
| 519 | bool check_async; |
| 520 | |
| 521 | /* |
| 522 | * Indicates if we are binding synchronous or asynchronous drivers. |
| 523 | * When asynchronous probing is enabled we'll execute 2 passes |
| 524 | * over drivers: first pass doing synchronous probing and second |
| 525 | * doing asynchronous probing (if synchronous did not succeed - |
| 526 | * most likely because there was no driver requiring synchronous |
| 527 | * probing - and we found asynchronous driver during first pass). |
| 528 | * The 2 passes are done because we can't shoot asynchronous |
| 529 | * probe for given device and driver from bus_for_each_drv() since |
| 530 | * driver pointer is not guaranteed to stay valid once |
| 531 | * bus_for_each_drv() iterates to the next driver on the bus. |
| 532 | */ |
| 533 | bool want_async; |
| 534 | |
| 535 | /* |
| 536 | * We'll set have_async to 'true' if, while scanning for matching |
| 537 | * driver, we'll encounter one that requests asynchronous probing. |
| 538 | */ |
| 539 | bool have_async; |
| 540 | }; |
| 541 | |
| 542 | static int __device_attach_driver(struct device_driver *drv, void *_data) |
| 543 | { |
| 544 | struct device_attach_data *data = _data; |
| 545 | struct device *dev = data->dev; |
| 546 | bool async_allowed; |
| 547 | |
| 548 | /* |
| 549 | * Check if device has already been claimed. This may |
| 550 | * happen with driver loading, device discovery/registration, |
| 551 | * and deferred probe processing happens all at once with |
| 552 | * multiple threads. |
| 553 | */ |
| 554 | if (dev->driver) |
| 555 | return -EBUSY; |
Ming Lei | 49b420a | 2009-01-21 23:27:47 +0800 | [diff] [blame] | 556 | |
| 557 | if (!driver_match_device(drv, dev)) |
| 558 | return 0; |
| 559 | |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 560 | async_allowed = driver_allows_async_probing(drv); |
| 561 | |
| 562 | if (async_allowed) |
| 563 | data->have_async = true; |
| 564 | |
| 565 | if (data->check_async && async_allowed != data->want_async) |
| 566 | return 0; |
| 567 | |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 568 | return driver_probe_device(drv, dev); |
mochel@digitalimplant.org | 2287c32 | 2005-03-24 10:50:24 -0800 | [diff] [blame] | 569 | } |
| 570 | |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 571 | static void __device_attach_async_helper(void *_dev, async_cookie_t cookie) |
| 572 | { |
| 573 | struct device *dev = _dev; |
| 574 | struct device_attach_data data = { |
| 575 | .dev = dev, |
| 576 | .check_async = true, |
| 577 | .want_async = true, |
| 578 | }; |
| 579 | |
| 580 | device_lock(dev); |
| 581 | |
Rafael J. Wysocki | ddef08d | 2015-07-27 18:03:58 +0300 | [diff] [blame] | 582 | if (dev->parent) |
| 583 | pm_runtime_get_sync(dev->parent); |
| 584 | |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 585 | bus_for_each_drv(dev->bus, NULL, &data, __device_attach_driver); |
| 586 | dev_dbg(dev, "async probe completed\n"); |
| 587 | |
| 588 | pm_request_idle(dev); |
| 589 | |
Rafael J. Wysocki | ddef08d | 2015-07-27 18:03:58 +0300 | [diff] [blame] | 590 | if (dev->parent) |
| 591 | pm_runtime_put(dev->parent); |
| 592 | |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 593 | device_unlock(dev); |
| 594 | |
| 595 | put_device(dev); |
| 596 | } |
| 597 | |
Dmitry Torokhov | 802a87f | 2015-05-20 16:36:31 -0700 | [diff] [blame] | 598 | static int __device_attach(struct device *dev, bool allow_async) |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 599 | { |
| 600 | int ret = 0; |
| 601 | |
| 602 | device_lock(dev); |
| 603 | if (dev->driver) { |
| 604 | if (klist_node_attached(&dev->p->knode_driver)) { |
| 605 | ret = 1; |
| 606 | goto out_unlock; |
| 607 | } |
| 608 | ret = device_bind_driver(dev); |
| 609 | if (ret == 0) |
| 610 | ret = 1; |
| 611 | else { |
| 612 | dev->driver = NULL; |
| 613 | ret = 0; |
| 614 | } |
| 615 | } else { |
| 616 | struct device_attach_data data = { |
| 617 | .dev = dev, |
| 618 | .check_async = allow_async, |
| 619 | .want_async = false, |
| 620 | }; |
| 621 | |
Rafael J. Wysocki | ddef08d | 2015-07-27 18:03:58 +0300 | [diff] [blame] | 622 | if (dev->parent) |
| 623 | pm_runtime_get_sync(dev->parent); |
| 624 | |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 625 | ret = bus_for_each_drv(dev->bus, NULL, &data, |
| 626 | __device_attach_driver); |
| 627 | if (!ret && allow_async && data.have_async) { |
| 628 | /* |
| 629 | * If we could not find appropriate driver |
| 630 | * synchronously and we are allowed to do |
| 631 | * async probes and there are drivers that |
| 632 | * want to probe asynchronously, we'll |
| 633 | * try them. |
| 634 | */ |
| 635 | dev_dbg(dev, "scheduling asynchronous probe\n"); |
| 636 | get_device(dev); |
| 637 | async_schedule(__device_attach_async_helper, dev); |
| 638 | } else { |
| 639 | pm_request_idle(dev); |
| 640 | } |
Rafael J. Wysocki | ddef08d | 2015-07-27 18:03:58 +0300 | [diff] [blame] | 641 | |
| 642 | if (dev->parent) |
| 643 | pm_runtime_put(dev->parent); |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 644 | } |
| 645 | out_unlock: |
| 646 | device_unlock(dev); |
| 647 | return ret; |
| 648 | } |
| 649 | |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 650 | /** |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 651 | * device_attach - try to attach device to a driver. |
| 652 | * @dev: device. |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 653 | * |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 654 | * Walk the list of drivers that the bus has and call |
| 655 | * driver_probe_device() for each pair. If a compatible |
| 656 | * pair is found, break out and return. |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 657 | * |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 658 | * Returns 1 if the device was bound to a driver; |
Dmitry Torokhov | 59a3cd7 | 2009-05-05 20:38:28 -0700 | [diff] [blame] | 659 | * 0 if no matching driver was found; |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 660 | * -ENODEV if the device is not registered. |
Alan Stern | bf74ad5 | 2005-11-17 16:54:12 -0500 | [diff] [blame] | 661 | * |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 662 | * When called for a USB interface, @dev->parent lock must be held. |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 663 | */ |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 664 | int device_attach(struct device *dev) |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 665 | { |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 666 | return __device_attach(dev, false); |
mochel@digitalimplant.org | 2287c32 | 2005-03-24 10:50:24 -0800 | [diff] [blame] | 667 | } |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 668 | EXPORT_SYMBOL_GPL(device_attach); |
mochel@digitalimplant.org | 2287c32 | 2005-03-24 10:50:24 -0800 | [diff] [blame] | 669 | |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 670 | void device_initial_probe(struct device *dev) |
| 671 | { |
| 672 | __device_attach(dev, true); |
| 673 | } |
| 674 | |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 675 | static int __driver_attach(struct device *dev, void *data) |
mochel@digitalimplant.org | 2287c32 | 2005-03-24 10:50:24 -0800 | [diff] [blame] | 676 | { |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 677 | struct device_driver *drv = data; |
mochel@digitalimplant.org | 2287c32 | 2005-03-24 10:50:24 -0800 | [diff] [blame] | 678 | |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 679 | /* |
| 680 | * Lock device and try to bind to it. We drop the error |
| 681 | * here and always return 0, because we need to keep trying |
| 682 | * to bind to devices and some drivers will return an error |
| 683 | * simply if it didn't support the device. |
| 684 | * |
| 685 | * driver_probe_device() will spit a warning if there |
| 686 | * is an error. |
| 687 | */ |
| 688 | |
Ming Lei | 49b420a | 2009-01-21 23:27:47 +0800 | [diff] [blame] | 689 | if (!driver_match_device(drv, dev)) |
Arjan van de Ven | 6cd4958 | 2008-09-14 08:32:06 -0700 | [diff] [blame] | 690 | return 0; |
| 691 | |
Alan Stern | bf74ad5 | 2005-11-17 16:54:12 -0500 | [diff] [blame] | 692 | if (dev->parent) /* Needed for USB */ |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 693 | device_lock(dev->parent); |
| 694 | device_lock(dev); |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 695 | if (!dev->driver) |
| 696 | driver_probe_device(drv, dev); |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 697 | device_unlock(dev); |
Alan Stern | bf74ad5 | 2005-11-17 16:54:12 -0500 | [diff] [blame] | 698 | if (dev->parent) |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 699 | device_unlock(dev->parent); |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 700 | |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 701 | return 0; |
| 702 | } |
| 703 | |
| 704 | /** |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 705 | * driver_attach - try to bind driver to devices. |
| 706 | * @drv: driver. |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 707 | * |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 708 | * Walk the list of devices that the bus has on it and try to |
| 709 | * match the driver with each one. If driver_probe_device() |
| 710 | * returns 0 and the @dev->driver is set, we've found a |
| 711 | * compatible pair. |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 712 | */ |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 713 | int driver_attach(struct device_driver *drv) |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 714 | { |
Andrew Morton | f86db39 | 2006-08-14 22:43:20 -0700 | [diff] [blame] | 715 | return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach); |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 716 | } |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 717 | EXPORT_SYMBOL_GPL(driver_attach); |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 718 | |
Stefan Richter | ab71c6f | 2007-06-17 11:02:12 +0200 | [diff] [blame] | 719 | /* |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 720 | * __device_release_driver() must be called with @dev lock held. |
| 721 | * When called for a USB interface, @dev->parent lock must be held as well. |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 722 | */ |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 723 | static void __device_release_driver(struct device *dev) |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 724 | { |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 725 | struct device_driver *drv; |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 726 | |
Alan Stern | ef2c517 | 2007-11-16 11:57:28 -0500 | [diff] [blame] | 727 | drv = dev->driver; |
Alan Stern | c95a6b0 | 2005-05-06 15:38:33 -0400 | [diff] [blame] | 728 | if (drv) { |
Dmitry Torokhov | 765230b | 2015-03-30 16:20:04 -0700 | [diff] [blame] | 729 | if (driver_allows_async_probing(drv)) |
| 730 | async_synchronize_full(); |
| 731 | |
Rafael J. Wysocki | e1866b3 | 2011-04-29 00:33:45 +0200 | [diff] [blame] | 732 | pm_runtime_get_sync(dev); |
Rafael J. Wysocki | 5e928f7 | 2009-08-18 23:38:32 +0200 | [diff] [blame] | 733 | |
Kay Sievers | 1901fb2 | 2006-10-07 21:55:55 +0200 | [diff] [blame] | 734 | driver_sysfs_remove(dev); |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 735 | |
Benjamin Herrenschmidt | 116af37 | 2006-10-25 13:44:59 +1000 | [diff] [blame] | 736 | if (dev->bus) |
Greg Kroah-Hartman | c6f7e72 | 2007-11-01 19:41:16 -0700 | [diff] [blame] | 737 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
Benjamin Herrenschmidt | 116af37 | 2006-10-25 13:44:59 +1000 | [diff] [blame] | 738 | BUS_NOTIFY_UNBIND_DRIVER, |
| 739 | dev); |
| 740 | |
Rafael J. Wysocki | baab52d | 2013-11-07 01:51:15 +0100 | [diff] [blame] | 741 | pm_runtime_put_sync(dev); |
Rafael J. Wysocki | e1866b3 | 2011-04-29 00:33:45 +0200 | [diff] [blame] | 742 | |
Alan Stern | 0f836ca | 2006-03-31 11:52:25 -0500 | [diff] [blame] | 743 | if (dev->bus && dev->bus->remove) |
Russell King | 594c828 | 2006-01-05 14:29:51 +0000 | [diff] [blame] | 744 | dev->bus->remove(dev); |
| 745 | else if (drv->remove) |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 746 | drv->remove(dev); |
Tejun Heo | 9ac7849 | 2007-01-20 16:00:26 +0900 | [diff] [blame] | 747 | devres_release_all(dev); |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 748 | dev->driver = NULL; |
Hans de Goede | 0998d06 | 2012-05-23 00:09:34 +0200 | [diff] [blame] | 749 | dev_set_drvdata(dev, NULL); |
Rafael J. Wysocki | e90d553 | 2015-03-20 13:59:27 +0100 | [diff] [blame] | 750 | if (dev->pm_domain && dev->pm_domain->dismiss) |
| 751 | dev->pm_domain->dismiss(dev); |
Ulf Hansson | 5de85b9 | 2015-11-18 11:48:39 +0100 | [diff] [blame] | 752 | pm_runtime_reinit(dev); |
Rafael J. Wysocki | e90d553 | 2015-03-20 13:59:27 +0100 | [diff] [blame] | 753 | |
Greg Kroah-Hartman | 8940b4f | 2008-12-16 12:25:49 -0800 | [diff] [blame] | 754 | klist_remove(&dev->p->knode_driver); |
Joerg Roedel | 309b7d6 | 2009-04-24 14:57:00 +0200 | [diff] [blame] | 755 | if (dev->bus) |
| 756 | blocking_notifier_call_chain(&dev->bus->p->bus_notifier, |
| 757 | BUS_NOTIFY_UNBOUND_DRIVER, |
| 758 | dev); |
Patrick Mochel | 0d3e5a2 | 2005-04-05 23:46:33 -0700 | [diff] [blame] | 759 | } |
Alan Stern | c95a6b0 | 2005-05-06 15:38:33 -0400 | [diff] [blame] | 760 | } |
| 761 | |
Stefan Richter | ab71c6f | 2007-06-17 11:02:12 +0200 | [diff] [blame] | 762 | /** |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 763 | * device_release_driver - manually detach device from driver. |
| 764 | * @dev: device. |
Stefan Richter | ab71c6f | 2007-06-17 11:02:12 +0200 | [diff] [blame] | 765 | * |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 766 | * Manually detach device from driver. |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 767 | * When called for a USB interface, @dev->parent lock must be held. |
Stefan Richter | ab71c6f | 2007-06-17 11:02:12 +0200 | [diff] [blame] | 768 | */ |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 769 | void device_release_driver(struct device *dev) |
Alan Stern | c95a6b0 | 2005-05-06 15:38:33 -0400 | [diff] [blame] | 770 | { |
| 771 | /* |
| 772 | * If anyone calls device_release_driver() recursively from |
| 773 | * within their ->remove callback for the same device, they |
| 774 | * will deadlock right here. |
| 775 | */ |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 776 | device_lock(dev); |
Alan Stern | c95a6b0 | 2005-05-06 15:38:33 -0400 | [diff] [blame] | 777 | __device_release_driver(dev); |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 778 | device_unlock(dev); |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 779 | } |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 780 | EXPORT_SYMBOL_GPL(device_release_driver); |
mochel@digitalimplant.org | 94e7b1c5 | 2005-03-21 12:25:36 -0800 | [diff] [blame] | 781 | |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 782 | /** |
| 783 | * driver_detach - detach driver from all devices it controls. |
| 784 | * @drv: driver. |
| 785 | */ |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 786 | void driver_detach(struct device_driver *drv) |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 787 | { |
Greg Kroah-Hartman | 8940b4f | 2008-12-16 12:25:49 -0800 | [diff] [blame] | 788 | struct device_private *dev_prv; |
Greg Kroah-Hartman | 4a3ad20 | 2008-01-24 22:50:12 -0800 | [diff] [blame] | 789 | struct device *dev; |
Alan Stern | c95a6b0 | 2005-05-06 15:38:33 -0400 | [diff] [blame] | 790 | |
| 791 | for (;;) { |
Greg Kroah-Hartman | e5dd127 | 2007-11-28 15:59:15 -0800 | [diff] [blame] | 792 | spin_lock(&drv->p->klist_devices.k_lock); |
| 793 | if (list_empty(&drv->p->klist_devices.k_list)) { |
| 794 | spin_unlock(&drv->p->klist_devices.k_lock); |
Alan Stern | c95a6b0 | 2005-05-06 15:38:33 -0400 | [diff] [blame] | 795 | break; |
| 796 | } |
Greg Kroah-Hartman | 8940b4f | 2008-12-16 12:25:49 -0800 | [diff] [blame] | 797 | dev_prv = list_entry(drv->p->klist_devices.k_list.prev, |
| 798 | struct device_private, |
| 799 | knode_driver.n_node); |
| 800 | dev = dev_prv->device; |
Alan Stern | c95a6b0 | 2005-05-06 15:38:33 -0400 | [diff] [blame] | 801 | get_device(dev); |
Greg Kroah-Hartman | e5dd127 | 2007-11-28 15:59:15 -0800 | [diff] [blame] | 802 | spin_unlock(&drv->p->klist_devices.k_lock); |
Alan Stern | c95a6b0 | 2005-05-06 15:38:33 -0400 | [diff] [blame] | 803 | |
Alan Stern | bf74ad5 | 2005-11-17 16:54:12 -0500 | [diff] [blame] | 804 | if (dev->parent) /* Needed for USB */ |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 805 | device_lock(dev->parent); |
| 806 | device_lock(dev); |
Alan Stern | c95a6b0 | 2005-05-06 15:38:33 -0400 | [diff] [blame] | 807 | if (dev->driver == drv) |
| 808 | __device_release_driver(dev); |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 809 | device_unlock(dev); |
Alan Stern | bf74ad5 | 2005-11-17 16:54:12 -0500 | [diff] [blame] | 810 | if (dev->parent) |
Greg Kroah-Hartman | 8e9394c | 2010-02-17 10:57:05 -0800 | [diff] [blame] | 811 | device_unlock(dev->parent); |
Alan Stern | c95a6b0 | 2005-05-06 15:38:33 -0400 | [diff] [blame] | 812 | put_device(dev); |
| 813 | } |
mochel@digitalimplant.org | 07e4a3e | 2005-03-21 10:52:54 -0800 | [diff] [blame] | 814 | } |