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20#include <linux/device.h>
21#include <linux/delay.h>
22#include <linux/module.h>
23#include <linux/kthread.h>
24#include <linux/wait.h>
25#include <linux/async.h>
26#include <linux/pm_runtime.h>
27
28#include "base.h"
29#include "power/power.h"
30
31
32static void driver_bound(struct device *dev)
33{
34 if (klist_node_attached(&dev->p->knode_driver)) {
35 printk(KERN_WARNING "%s: device %s already bound\n",
36 __func__, kobject_name(&dev->kobj));
37 return;
38 }
39
40 pr_debug("driver: '%s': %s: bound to device '%s'\n", dev_name(dev),
41 __func__, dev->driver->name);
42
43 klist_add_tail(&dev->p->knode_driver, &dev->driver->p->klist_devices);
44
45 if (dev->bus)
46 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
47 BUS_NOTIFY_BOUND_DRIVER, dev);
48}
49
50static int driver_sysfs_add(struct device *dev)
51{
52 int ret;
53
54 if (dev->bus)
55 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
56 BUS_NOTIFY_BIND_DRIVER, dev);
57
58 ret = sysfs_create_link(&dev->driver->p->kobj, &dev->kobj,
59 kobject_name(&dev->kobj));
60 if (ret == 0) {
61 ret = sysfs_create_link(&dev->kobj, &dev->driver->p->kobj,
62 "driver");
63 if (ret)
64 sysfs_remove_link(&dev->driver->p->kobj,
65 kobject_name(&dev->kobj));
66 }
67 return ret;
68}
69
70static void driver_sysfs_remove(struct device *dev)
71{
72 struct device_driver *drv = dev->driver;
73
74 if (drv) {
75 sysfs_remove_link(&drv->p->kobj, kobject_name(&dev->kobj));
76 sysfs_remove_link(&dev->kobj, "driver");
77 }
78}
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93
94int device_bind_driver(struct device *dev)
95{
96 int ret;
97
98 ret = driver_sysfs_add(dev);
99 if (!ret)
100 driver_bound(dev);
101 return ret;
102}
103EXPORT_SYMBOL_GPL(device_bind_driver);
104
105static atomic_t probe_count = ATOMIC_INIT(0);
106static DECLARE_WAIT_QUEUE_HEAD(probe_waitqueue);
107
108static int really_probe(struct device *dev, struct device_driver *drv)
109{
110 int ret = 0;
111
112 atomic_inc(&probe_count);
113 pr_debug("bus: '%s': %s: probing driver %s with device %s\n",
114 drv->bus->name, __func__, drv->name, dev_name(dev));
115 WARN_ON(!list_empty(&dev->devres_head));
116
117 dev->driver = drv;
118 if (driver_sysfs_add(dev)) {
119 printk(KERN_ERR "%s: driver_sysfs_add(%s) failed\n",
120 __func__, dev_name(dev));
121 goto probe_failed;
122 }
123
124 if (dev->bus->probe) {
125 ret = dev->bus->probe(dev);
126 if (ret)
127 goto probe_failed;
128 } else if (drv->probe) {
129 ret = drv->probe(dev);
130 if (ret)
131 goto probe_failed;
132 }
133
134 driver_bound(dev);
135 ret = 1;
136 pr_debug("bus: '%s': %s: bound device %s to driver %s\n",
137 drv->bus->name, __func__, dev_name(dev), drv->name);
138 goto done;
139
140probe_failed:
141 devres_release_all(dev);
142 driver_sysfs_remove(dev);
143 dev->driver = NULL;
144
145 if (ret != -ENODEV && ret != -ENXIO) {
146
147 printk(KERN_WARNING
148 "%s: probe of %s failed with error %d\n",
149 drv->name, dev_name(dev), ret);
150 }
151
152
153
154
155 ret = 0;
156done:
157 atomic_dec(&probe_count);
158 wake_up(&probe_waitqueue);
159 return ret;
160}
161
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166
167
168int driver_probe_done(void)
169{
170 pr_debug("%s: probe_count = %d\n", __func__,
171 atomic_read(&probe_count));
172 if (atomic_read(&probe_count))
173 return -EBUSY;
174 return 0;
175}
176
177
178
179
180
181void wait_for_device_probe(void)
182{
183
184 wait_event(probe_waitqueue, atomic_read(&probe_count) == 0);
185 async_synchronize_full();
186}
187EXPORT_SYMBOL_GPL(wait_for_device_probe);
188
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198
199
200int driver_probe_device(struct device_driver *drv, struct device *dev)
201{
202 int ret = 0;
203
204 if (!device_is_registered(dev))
205 return -ENODEV;
206
207 pr_debug("bus: '%s': %s: matched device %s with driver %s\n",
208 drv->bus->name, __func__, dev_name(dev), drv->name);
209
210 pm_runtime_get_noresume(dev);
211 pm_runtime_barrier(dev);
212 ret = really_probe(dev, drv);
213 pm_runtime_put_sync(dev);
214
215 return ret;
216}
217
218static int __device_attach(struct device_driver *drv, void *data)
219{
220 struct device *dev = data;
221
222 if (!driver_match_device(drv, dev))
223 return 0;
224
225 return driver_probe_device(drv, dev);
226}
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241
242int device_attach(struct device *dev)
243{
244 int ret = 0;
245
246 device_lock(dev);
247 if (dev->driver) {
248 if (klist_node_attached(&dev->p->knode_driver)) {
249 ret = 1;
250 goto out_unlock;
251 }
252 ret = device_bind_driver(dev);
253 if (ret == 0)
254 ret = 1;
255 else {
256 dev->driver = NULL;
257 ret = 0;
258 }
259 } else {
260 pm_runtime_get_noresume(dev);
261 ret = bus_for_each_drv(dev->bus, NULL, dev, __device_attach);
262 pm_runtime_put_sync(dev);
263 }
264out_unlock:
265 device_unlock(dev);
266 return ret;
267}
268EXPORT_SYMBOL_GPL(device_attach);
269
270static int __driver_attach(struct device *dev, void *data)
271{
272 struct device_driver *drv = data;
273
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282
283
284 if (!driver_match_device(drv, dev))
285 return 0;
286
287 if (dev->parent)
288 device_lock(dev->parent);
289 device_lock(dev);
290 if (!dev->driver)
291 driver_probe_device(drv, dev);
292 device_unlock(dev);
293 if (dev->parent)
294 device_unlock(dev->parent);
295
296 return 0;
297}
298
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306
307
308int driver_attach(struct device_driver *drv)
309{
310 return bus_for_each_dev(drv->bus, NULL, drv, __driver_attach);
311}
312EXPORT_SYMBOL_GPL(driver_attach);
313
314
315
316
317
318static void __device_release_driver(struct device *dev)
319{
320 struct device_driver *drv;
321
322 drv = dev->driver;
323 if (drv) {
324 pm_runtime_get_sync(dev);
325
326 driver_sysfs_remove(dev);
327
328 if (dev->bus)
329 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
330 BUS_NOTIFY_UNBIND_DRIVER,
331 dev);
332
333 pm_runtime_put_sync(dev);
334
335 if (dev->bus && dev->bus->remove)
336 dev->bus->remove(dev);
337 else if (drv->remove)
338 drv->remove(dev);
339 devres_release_all(dev);
340 dev->driver = NULL;
341 klist_remove(&dev->p->knode_driver);
342 if (dev->bus)
343 blocking_notifier_call_chain(&dev->bus->p->bus_notifier,
344 BUS_NOTIFY_UNBOUND_DRIVER,
345 dev);
346
347 }
348}
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356
357void device_release_driver(struct device *dev)
358{
359
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363
364 device_lock(dev);
365 __device_release_driver(dev);
366 device_unlock(dev);
367}
368EXPORT_SYMBOL_GPL(device_release_driver);
369
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373
374void driver_detach(struct device_driver *drv)
375{
376 struct device_private *dev_prv;
377 struct device *dev;
378
379 for (;;) {
380 spin_lock(&drv->p->klist_devices.k_lock);
381 if (list_empty(&drv->p->klist_devices.k_list)) {
382 spin_unlock(&drv->p->klist_devices.k_lock);
383 break;
384 }
385 dev_prv = list_entry(drv->p->klist_devices.k_list.prev,
386 struct device_private,
387 knode_driver.n_node);
388 dev = dev_prv->device;
389 get_device(dev);
390 spin_unlock(&drv->p->klist_devices.k_lock);
391
392 if (dev->parent)
393 device_lock(dev->parent);
394 device_lock(dev);
395 if (dev->driver == drv)
396 __device_release_driver(dev);
397 device_unlock(dev);
398 if (dev->parent)
399 device_unlock(dev->parent);
400 put_device(dev);
401 }
402}
403
404
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406
407
408void *dev_get_drvdata(const struct device *dev)
409{
410 if (dev && dev->p)
411 return dev->p->driver_data;
412 return NULL;
413}
414EXPORT_SYMBOL(dev_get_drvdata);
415
416int dev_set_drvdata(struct device *dev, void *data)
417{
418 int error;
419
420 if (!dev->p) {
421 error = device_private_init(dev);
422 if (error)
423 return error;
424 }
425 dev->p->driver_data = data;
426 return 0;
427}
428EXPORT_SYMBOL(dev_set_drvdata);
429