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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * dock.c - ACPI dock station driver
4 *
5 * Copyright (C) 2006, 2014, Intel Corp.
6 * Author: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
7 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
8 */
9
10#include <linux/kernel.h>
11#include <linux/moduleparam.h>
12#include <linux/slab.h>
13#include <linux/init.h>
14#include <linux/types.h>
15#include <linux/notifier.h>
16#include <linux/platform_device.h>
17#include <linux/jiffies.h>
18#include <linux/stddef.h>
19#include <linux/acpi.h>
20
21#include "internal.h"
22
23ACPI_MODULE_NAME("dock");
24
25static bool immediate_undock = 1;
26module_param(immediate_undock, bool, 0644);
27MODULE_PARM_DESC(immediate_undock, "1 (default) will cause the driver to "
28 "undock immediately when the undock button is pressed, 0 will cause"
29 " the driver to wait for userspace to write the undock sysfs file "
30 " before undocking");
31
32struct dock_station {
33 acpi_handle handle;
34 unsigned long last_dock_time;
35 u32 flags;
36 struct list_head dependent_devices;
37
38 struct list_head sibling;
39 struct platform_device *dock_device;
40};
41static LIST_HEAD(dock_stations);
42static int dock_station_count;
43
44struct dock_dependent_device {
45 struct list_head list;
46 struct acpi_device *adev;
47};
48
49#define DOCK_DOCKING 0x00000001
50#define DOCK_UNDOCKING 0x00000002
51#define DOCK_IS_DOCK 0x00000010
52#define DOCK_IS_ATA 0x00000020
53#define DOCK_IS_BAT 0x00000040
54#define DOCK_EVENT 3
55#define UNDOCK_EVENT 2
56
57enum dock_callback_type {
58 DOCK_CALL_HANDLER,
59 DOCK_CALL_FIXUP,
60 DOCK_CALL_UEVENT,
61};
62
63/*****************************************************************************
64 * Dock Dependent device functions *
65 *****************************************************************************/
66/**
67 * add_dock_dependent_device - associate a device with the dock station
68 * @ds: Dock station.
69 * @adev: Dependent ACPI device object.
70 *
71 * Add the dependent device to the dock's dependent device list.
72 */
73static int add_dock_dependent_device(struct dock_station *ds,
74 struct acpi_device *adev)
75{
76 struct dock_dependent_device *dd;
77
78 dd = kzalloc(sizeof(*dd), GFP_KERNEL);
79 if (!dd)
80 return -ENOMEM;
81
82 dd->adev = adev;
83 INIT_LIST_HEAD(&dd->list);
84 list_add_tail(&dd->list, &ds->dependent_devices);
85
86 return 0;
87}
88
89static void dock_hotplug_event(struct dock_dependent_device *dd, u32 event,
90 enum dock_callback_type cb_type)
91{
92 struct acpi_device *adev = dd->adev;
93
94 acpi_lock_hp_context();
95
96 if (!adev->hp)
97 goto out;
98
99 if (cb_type == DOCK_CALL_FIXUP) {
100 void (*fixup)(struct acpi_device *);
101
102 fixup = adev->hp->fixup;
103 if (fixup) {
104 acpi_unlock_hp_context();
105 fixup(adev);
106 return;
107 }
108 } else if (cb_type == DOCK_CALL_UEVENT) {
109 void (*uevent)(struct acpi_device *, u32);
110
111 uevent = adev->hp->uevent;
112 if (uevent) {
113 acpi_unlock_hp_context();
114 uevent(adev, event);
115 return;
116 }
117 } else {
118 int (*notify)(struct acpi_device *, u32);
119
120 notify = adev->hp->notify;
121 if (notify) {
122 acpi_unlock_hp_context();
123 notify(adev, event);
124 return;
125 }
126 }
127
128 out:
129 acpi_unlock_hp_context();
130}
131
132static struct dock_station *find_dock_station(acpi_handle handle)
133{
134 struct dock_station *ds;
135
136 list_for_each_entry(ds, &dock_stations, sibling)
137 if (ds->handle == handle)
138 return ds;
139
140 return NULL;
141}
142
143/**
144 * find_dock_dependent_device - get a device dependent on this dock
145 * @ds: the dock station
146 * @adev: ACPI device object to find.
147 *
148 * iterate over the dependent device list for this dock. If the
149 * dependent device matches the handle, return.
150 */
151static struct dock_dependent_device *
152find_dock_dependent_device(struct dock_station *ds, struct acpi_device *adev)
153{
154 struct dock_dependent_device *dd;
155
156 list_for_each_entry(dd, &ds->dependent_devices, list)
157 if (adev == dd->adev)
158 return dd;
159
160 return NULL;
161}
162
163void register_dock_dependent_device(struct acpi_device *adev,
164 acpi_handle dshandle)
165{
166 struct dock_station *ds = find_dock_station(dshandle);
167
168 if (ds && !find_dock_dependent_device(ds, adev))
169 add_dock_dependent_device(ds, adev);
170}
171
172/*****************************************************************************
173 * Dock functions *
174 *****************************************************************************/
175
176/**
177 * is_dock_device - see if a device is on a dock station
178 * @adev: ACPI device object to check.
179 *
180 * If this device is either the dock station itself,
181 * or is a device dependent on the dock station, then it
182 * is a dock device
183 */
184int is_dock_device(struct acpi_device *adev)
185{
186 struct dock_station *dock_station;
187
188 if (!dock_station_count)
189 return 0;
190
191 if (acpi_dock_match(adev->handle))
192 return 1;
193
194 list_for_each_entry(dock_station, &dock_stations, sibling)
195 if (find_dock_dependent_device(dock_station, adev))
196 return 1;
197
198 return 0;
199}
200EXPORT_SYMBOL_GPL(is_dock_device);
201
202/**
203 * dock_present - see if the dock station is present.
204 * @ds: the dock station
205 *
206 * execute the _STA method. note that present does not
207 * imply that we are docked.
208 */
209static int dock_present(struct dock_station *ds)
210{
211 unsigned long long sta;
212 acpi_status status;
213
214 if (ds) {
215 status = acpi_evaluate_integer(ds->handle, "_STA", NULL, &sta);
216 if (ACPI_SUCCESS(status) && sta)
217 return 1;
218 }
219 return 0;
220}
221
222/**
223 * hot_remove_dock_devices - Remove dock station devices.
224 * @ds: Dock station.
225 */
226static void hot_remove_dock_devices(struct dock_station *ds)
227{
228 struct dock_dependent_device *dd;
229
230 /*
231 * Walk the list in reverse order so that devices that have been added
232 * last are removed first (in case there are some indirect dependencies
233 * between them).
234 */
235 list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
236 dock_hotplug_event(dd, ACPI_NOTIFY_EJECT_REQUEST, false);
237
238 list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
239 acpi_bus_trim(dd->adev);
240}
241
242/**
243 * hotplug_dock_devices - Insert devices on a dock station.
244 * @ds: the dock station
245 * @event: either bus check or device check request
246 *
247 * Some devices on the dock station need to have drivers called
248 * to perform hotplug operations after a dock event has occurred.
249 * Traverse the list of dock devices that have registered a
250 * hotplug handler, and call the handler.
251 */
252static void hotplug_dock_devices(struct dock_station *ds, u32 event)
253{
254 struct dock_dependent_device *dd;
255
256 /* Call driver specific post-dock fixups. */
257 list_for_each_entry(dd, &ds->dependent_devices, list)
258 dock_hotplug_event(dd, event, DOCK_CALL_FIXUP);
259
260 /* Call driver specific hotplug functions. */
261 list_for_each_entry(dd, &ds->dependent_devices, list)
262 dock_hotplug_event(dd, event, DOCK_CALL_HANDLER);
263
264 /*
265 * Check if all devices have been enumerated already. If not, run
266 * acpi_bus_scan() for them and that will cause scan handlers to be
267 * attached to device objects or acpi_drivers to be stopped/started if
268 * they are present.
269 */
270 list_for_each_entry(dd, &ds->dependent_devices, list) {
271 struct acpi_device *adev = dd->adev;
272
273 if (!acpi_device_enumerated(adev)) {
274 int ret = acpi_bus_scan(adev->handle);
275 if (ret)
276 dev_dbg(&adev->dev, "scan error %d\n", -ret);
277 }
278 }
279}
280
281static void dock_event(struct dock_station *ds, u32 event, int num)
282{
283 struct device *dev = &ds->dock_device->dev;
284 char event_string[13];
285 char *envp[] = { event_string, NULL };
286 struct dock_dependent_device *dd;
287
288 if (num == UNDOCK_EVENT)
289 sprintf(event_string, "EVENT=undock");
290 else
291 sprintf(event_string, "EVENT=dock");
292
293 /*
294 * Indicate that the status of the dock station has
295 * changed.
296 */
297 if (num == DOCK_EVENT)
298 kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
299
300 list_for_each_entry(dd, &ds->dependent_devices, list)
301 dock_hotplug_event(dd, event, DOCK_CALL_UEVENT);
302
303 if (num != DOCK_EVENT)
304 kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
305}
306
307/**
308 * handle_dock - handle a dock event
309 * @ds: the dock station
310 * @dock: to dock, or undock - that is the question
311 *
312 * Execute the _DCK method in response to an acpi event
313 */
314static void handle_dock(struct dock_station *ds, int dock)
315{
316 acpi_status status;
317 struct acpi_object_list arg_list;
318 union acpi_object arg;
319 unsigned long long value;
320
321 acpi_handle_info(ds->handle, "%s\n", dock ? "docking" : "undocking");
322
323 /* _DCK method has one argument */
324 arg_list.count = 1;
325 arg_list.pointer = &arg;
326 arg.type = ACPI_TYPE_INTEGER;
327 arg.integer.value = dock;
328 status = acpi_evaluate_integer(ds->handle, "_DCK", &arg_list, &value);
329 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
330 acpi_handle_err(ds->handle, "Failed to execute _DCK (0x%x)\n",
331 status);
332}
333
334static inline void dock(struct dock_station *ds)
335{
336 handle_dock(ds, 1);
337}
338
339static inline void undock(struct dock_station *ds)
340{
341 handle_dock(ds, 0);
342}
343
344static inline void begin_dock(struct dock_station *ds)
345{
346 ds->flags |= DOCK_DOCKING;
347}
348
349static inline void complete_dock(struct dock_station *ds)
350{
351 ds->flags &= ~(DOCK_DOCKING);
352 ds->last_dock_time = jiffies;
353}
354
355static inline void begin_undock(struct dock_station *ds)
356{
357 ds->flags |= DOCK_UNDOCKING;
358}
359
360static inline void complete_undock(struct dock_station *ds)
361{
362 ds->flags &= ~(DOCK_UNDOCKING);
363}
364
365/**
366 * dock_in_progress - see if we are in the middle of handling a dock event
367 * @ds: the dock station
368 *
369 * Sometimes while docking, false dock events can be sent to the driver
370 * because good connections aren't made or some other reason. Ignore these
371 * if we are in the middle of doing something.
372 */
373static int dock_in_progress(struct dock_station *ds)
374{
375 if ((ds->flags & DOCK_DOCKING) ||
376 time_before(jiffies, (ds->last_dock_time + HZ)))
377 return 1;
378 return 0;
379}
380
381/**
382 * handle_eject_request - handle an undock request checking for error conditions
383 *
384 * Check to make sure the dock device is still present, then undock and
385 * hotremove all the devices that may need removing.
386 */
387static int handle_eject_request(struct dock_station *ds, u32 event)
388{
389 if (dock_in_progress(ds))
390 return -EBUSY;
391
392 /*
393 * here we need to generate the undock
394 * event prior to actually doing the undock
395 * so that the device struct still exists.
396 * Also, even send the dock event if the
397 * device is not present anymore
398 */
399 dock_event(ds, event, UNDOCK_EVENT);
400
401 hot_remove_dock_devices(ds);
402 undock(ds);
403 acpi_evaluate_lck(ds->handle, 0);
404 acpi_evaluate_ej0(ds->handle);
405 if (dock_present(ds)) {
406 acpi_handle_err(ds->handle, "Unable to undock!\n");
407 return -EBUSY;
408 }
409 complete_undock(ds);
410 return 0;
411}
412
413/**
414 * dock_notify - Handle ACPI dock notification.
415 * @adev: Dock station's ACPI device object.
416 * @event: Event code.
417 *
418 * If we are notified to dock, then check to see if the dock is
419 * present and then dock. Notify all drivers of the dock event,
420 * and then hotplug and devices that may need hotplugging.
421 */
422int dock_notify(struct acpi_device *adev, u32 event)
423{
424 acpi_handle handle = adev->handle;
425 struct dock_station *ds = find_dock_station(handle);
426 int surprise_removal = 0;
427
428 if (!ds)
429 return -ENODEV;
430
431 /*
432 * According to acpi spec 3.0a, if a DEVICE_CHECK notification
433 * is sent and _DCK is present, it is assumed to mean an undock
434 * request.
435 */
436 if ((ds->flags & DOCK_IS_DOCK) && event == ACPI_NOTIFY_DEVICE_CHECK)
437 event = ACPI_NOTIFY_EJECT_REQUEST;
438
439 /*
440 * dock station: BUS_CHECK - docked or surprise removal
441 * DEVICE_CHECK - undocked
442 * other device: BUS_CHECK/DEVICE_CHECK - added or surprise removal
443 *
444 * To simplify event handling, dock dependent device handler always
445 * get ACPI_NOTIFY_BUS_CHECK/ACPI_NOTIFY_DEVICE_CHECK for add and
446 * ACPI_NOTIFY_EJECT_REQUEST for removal
447 */
448 switch (event) {
449 case ACPI_NOTIFY_BUS_CHECK:
450 case ACPI_NOTIFY_DEVICE_CHECK:
451 if (!dock_in_progress(ds) && !acpi_device_enumerated(adev)) {
452 begin_dock(ds);
453 dock(ds);
454 if (!dock_present(ds)) {
455 acpi_handle_err(handle, "Unable to dock!\n");
456 complete_dock(ds);
457 break;
458 }
459 hotplug_dock_devices(ds, event);
460 complete_dock(ds);
461 dock_event(ds, event, DOCK_EVENT);
462 acpi_evaluate_lck(ds->handle, 1);
463 acpi_update_all_gpes();
464 break;
465 }
466 if (dock_present(ds) || dock_in_progress(ds))
467 break;
468 /* This is a surprise removal */
469 surprise_removal = 1;
470 event = ACPI_NOTIFY_EJECT_REQUEST;
471 /* Fall back */
472 fallthrough;
473 case ACPI_NOTIFY_EJECT_REQUEST:
474 begin_undock(ds);
475 if ((immediate_undock && !(ds->flags & DOCK_IS_ATA))
476 || surprise_removal)
477 handle_eject_request(ds, event);
478 else
479 dock_event(ds, event, UNDOCK_EVENT);
480 break;
481 }
482 return 0;
483}
484
485/*
486 * show_docked - read method for "docked" file in sysfs
487 */
488static ssize_t show_docked(struct device *dev,
489 struct device_attribute *attr, char *buf)
490{
491 struct dock_station *dock_station = dev->platform_data;
492 struct acpi_device *adev = NULL;
493
494 acpi_bus_get_device(dock_station->handle, &adev);
495 return snprintf(buf, PAGE_SIZE, "%u\n", acpi_device_enumerated(adev));
496}
497static DEVICE_ATTR(docked, S_IRUGO, show_docked, NULL);
498
499/*
500 * show_flags - read method for flags file in sysfs
501 */
502static ssize_t show_flags(struct device *dev,
503 struct device_attribute *attr, char *buf)
504{
505 struct dock_station *dock_station = dev->platform_data;
506 return snprintf(buf, PAGE_SIZE, "%d\n", dock_station->flags);
507
508}
509static DEVICE_ATTR(flags, S_IRUGO, show_flags, NULL);
510
511/*
512 * write_undock - write method for "undock" file in sysfs
513 */
514static ssize_t write_undock(struct device *dev, struct device_attribute *attr,
515 const char *buf, size_t count)
516{
517 int ret;
518 struct dock_station *dock_station = dev->platform_data;
519
520 if (!count)
521 return -EINVAL;
522
523 acpi_scan_lock_acquire();
524 begin_undock(dock_station);
525 ret = handle_eject_request(dock_station, ACPI_NOTIFY_EJECT_REQUEST);
526 acpi_scan_lock_release();
527 return ret ? ret: count;
528}
529static DEVICE_ATTR(undock, S_IWUSR, NULL, write_undock);
530
531/*
532 * show_dock_uid - read method for "uid" file in sysfs
533 */
534static ssize_t show_dock_uid(struct device *dev,
535 struct device_attribute *attr, char *buf)
536{
537 unsigned long long lbuf;
538 struct dock_station *dock_station = dev->platform_data;
539 acpi_status status = acpi_evaluate_integer(dock_station->handle,
540 "_UID", NULL, &lbuf);
541 if (ACPI_FAILURE(status))
542 return 0;
543
544 return snprintf(buf, PAGE_SIZE, "%llx\n", lbuf);
545}
546static DEVICE_ATTR(uid, S_IRUGO, show_dock_uid, NULL);
547
548static ssize_t show_dock_type(struct device *dev,
549 struct device_attribute *attr, char *buf)
550{
551 struct dock_station *dock_station = dev->platform_data;
552 char *type;
553
554 if (dock_station->flags & DOCK_IS_DOCK)
555 type = "dock_station";
556 else if (dock_station->flags & DOCK_IS_ATA)
557 type = "ata_bay";
558 else if (dock_station->flags & DOCK_IS_BAT)
559 type = "battery_bay";
560 else
561 type = "unknown";
562
563 return snprintf(buf, PAGE_SIZE, "%s\n", type);
564}
565static DEVICE_ATTR(type, S_IRUGO, show_dock_type, NULL);
566
567static struct attribute *dock_attributes[] = {
568 &dev_attr_docked.attr,
569 &dev_attr_flags.attr,
570 &dev_attr_undock.attr,
571 &dev_attr_uid.attr,
572 &dev_attr_type.attr,
573 NULL
574};
575
576static const struct attribute_group dock_attribute_group = {
577 .attrs = dock_attributes
578};
579
580/**
581 * acpi_dock_add - Add a new dock station
582 * @adev: Dock station ACPI device object.
583 *
584 * allocated and initialize a new dock station device.
585 */
586void acpi_dock_add(struct acpi_device *adev)
587{
588 struct dock_station *dock_station, ds = { NULL, };
589 struct platform_device_info pdevinfo;
590 acpi_handle handle = adev->handle;
591 struct platform_device *dd;
592 int ret;
593
594 memset(&pdevinfo, 0, sizeof(pdevinfo));
595 pdevinfo.name = "dock";
596 pdevinfo.id = dock_station_count;
597 pdevinfo.fwnode = acpi_fwnode_handle(adev);
598 pdevinfo.data = &ds;
599 pdevinfo.size_data = sizeof(ds);
600 dd = platform_device_register_full(&pdevinfo);
601 if (IS_ERR(dd))
602 return;
603
604 dock_station = dd->dev.platform_data;
605
606 dock_station->handle = handle;
607 dock_station->dock_device = dd;
608 dock_station->last_dock_time = jiffies - HZ;
609
610 INIT_LIST_HEAD(&dock_station->sibling);
611 INIT_LIST_HEAD(&dock_station->dependent_devices);
612
613 /* we want the dock device to send uevents */
614 dev_set_uevent_suppress(&dd->dev, 0);
615
616 if (acpi_dock_match(handle))
617 dock_station->flags |= DOCK_IS_DOCK;
618 if (acpi_ata_match(handle))
619 dock_station->flags |= DOCK_IS_ATA;
620 if (acpi_device_is_battery(adev))
621 dock_station->flags |= DOCK_IS_BAT;
622
623 ret = sysfs_create_group(&dd->dev.kobj, &dock_attribute_group);
624 if (ret)
625 goto err_unregister;
626
627 /* add the dock station as a device dependent on itself */
628 ret = add_dock_dependent_device(dock_station, adev);
629 if (ret)
630 goto err_rmgroup;
631
632 dock_station_count++;
633 list_add(&dock_station->sibling, &dock_stations);
634 adev->flags.is_dock_station = true;
635 dev_info(&adev->dev, "ACPI dock station (docks/bays count: %d)\n",
636 dock_station_count);
637 return;
638
639err_rmgroup:
640 sysfs_remove_group(&dd->dev.kobj, &dock_attribute_group);
641
642err_unregister:
643 platform_device_unregister(dd);
644 acpi_handle_err(handle, "%s encountered error %d\n", __func__, ret);
645}
1/*
2 * dock.c - ACPI dock station driver
3 *
4 * Copyright (C) 2006, 2014, Intel Corp.
5 * Author: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
6 * Rafael J. Wysocki <rafael.j.wysocki@intel.com>
7 *
8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or (at
13 * your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful, but
16 * WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 * General Public License for more details.
19 *
20 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
21 */
22
23#include <linux/kernel.h>
24#include <linux/module.h>
25#include <linux/slab.h>
26#include <linux/init.h>
27#include <linux/types.h>
28#include <linux/notifier.h>
29#include <linux/platform_device.h>
30#include <linux/jiffies.h>
31#include <linux/stddef.h>
32#include <linux/acpi.h>
33
34#include "internal.h"
35
36#define ACPI_DOCK_DRIVER_DESCRIPTION "ACPI Dock Station Driver"
37
38ACPI_MODULE_NAME("dock");
39MODULE_AUTHOR("Kristen Carlson Accardi");
40MODULE_DESCRIPTION(ACPI_DOCK_DRIVER_DESCRIPTION);
41MODULE_LICENSE("GPL");
42
43static bool immediate_undock = 1;
44module_param(immediate_undock, bool, 0644);
45MODULE_PARM_DESC(immediate_undock, "1 (default) will cause the driver to "
46 "undock immediately when the undock button is pressed, 0 will cause"
47 " the driver to wait for userspace to write the undock sysfs file "
48 " before undocking");
49
50struct dock_station {
51 acpi_handle handle;
52 unsigned long last_dock_time;
53 u32 flags;
54 struct list_head dependent_devices;
55
56 struct list_head sibling;
57 struct platform_device *dock_device;
58};
59static LIST_HEAD(dock_stations);
60static int dock_station_count;
61
62struct dock_dependent_device {
63 struct list_head list;
64 struct acpi_device *adev;
65};
66
67#define DOCK_DOCKING 0x00000001
68#define DOCK_UNDOCKING 0x00000002
69#define DOCK_IS_DOCK 0x00000010
70#define DOCK_IS_ATA 0x00000020
71#define DOCK_IS_BAT 0x00000040
72#define DOCK_EVENT 3
73#define UNDOCK_EVENT 2
74
75enum dock_callback_type {
76 DOCK_CALL_HANDLER,
77 DOCK_CALL_FIXUP,
78 DOCK_CALL_UEVENT,
79};
80
81/*****************************************************************************
82 * Dock Dependent device functions *
83 *****************************************************************************/
84/**
85 * add_dock_dependent_device - associate a device with the dock station
86 * @ds: Dock station.
87 * @adev: Dependent ACPI device object.
88 *
89 * Add the dependent device to the dock's dependent device list.
90 */
91static int add_dock_dependent_device(struct dock_station *ds,
92 struct acpi_device *adev)
93{
94 struct dock_dependent_device *dd;
95
96 dd = kzalloc(sizeof(*dd), GFP_KERNEL);
97 if (!dd)
98 return -ENOMEM;
99
100 dd->adev = adev;
101 INIT_LIST_HEAD(&dd->list);
102 list_add_tail(&dd->list, &ds->dependent_devices);
103
104 return 0;
105}
106
107static void dock_hotplug_event(struct dock_dependent_device *dd, u32 event,
108 enum dock_callback_type cb_type)
109{
110 struct acpi_device *adev = dd->adev;
111
112 acpi_lock_hp_context();
113
114 if (!adev->hp)
115 goto out;
116
117 if (cb_type == DOCK_CALL_FIXUP) {
118 void (*fixup)(struct acpi_device *);
119
120 fixup = adev->hp->fixup;
121 if (fixup) {
122 acpi_unlock_hp_context();
123 fixup(adev);
124 return;
125 }
126 } else if (cb_type == DOCK_CALL_UEVENT) {
127 void (*uevent)(struct acpi_device *, u32);
128
129 uevent = adev->hp->uevent;
130 if (uevent) {
131 acpi_unlock_hp_context();
132 uevent(adev, event);
133 return;
134 }
135 } else {
136 int (*notify)(struct acpi_device *, u32);
137
138 notify = adev->hp->notify;
139 if (notify) {
140 acpi_unlock_hp_context();
141 notify(adev, event);
142 return;
143 }
144 }
145
146 out:
147 acpi_unlock_hp_context();
148}
149
150static struct dock_station *find_dock_station(acpi_handle handle)
151{
152 struct dock_station *ds;
153
154 list_for_each_entry(ds, &dock_stations, sibling)
155 if (ds->handle == handle)
156 return ds;
157
158 return NULL;
159}
160
161/**
162 * find_dock_dependent_device - get a device dependent on this dock
163 * @ds: the dock station
164 * @adev: ACPI device object to find.
165 *
166 * iterate over the dependent device list for this dock. If the
167 * dependent device matches the handle, return.
168 */
169static struct dock_dependent_device *
170find_dock_dependent_device(struct dock_station *ds, struct acpi_device *adev)
171{
172 struct dock_dependent_device *dd;
173
174 list_for_each_entry(dd, &ds->dependent_devices, list)
175 if (adev == dd->adev)
176 return dd;
177
178 return NULL;
179}
180
181void register_dock_dependent_device(struct acpi_device *adev,
182 acpi_handle dshandle)
183{
184 struct dock_station *ds = find_dock_station(dshandle);
185
186 if (ds && !find_dock_dependent_device(ds, adev))
187 add_dock_dependent_device(ds, adev);
188}
189
190/*****************************************************************************
191 * Dock functions *
192 *****************************************************************************/
193
194/**
195 * is_dock_device - see if a device is on a dock station
196 * @adev: ACPI device object to check.
197 *
198 * If this device is either the dock station itself,
199 * or is a device dependent on the dock station, then it
200 * is a dock device
201 */
202int is_dock_device(struct acpi_device *adev)
203{
204 struct dock_station *dock_station;
205
206 if (!dock_station_count)
207 return 0;
208
209 if (acpi_dock_match(adev->handle))
210 return 1;
211
212 list_for_each_entry(dock_station, &dock_stations, sibling)
213 if (find_dock_dependent_device(dock_station, adev))
214 return 1;
215
216 return 0;
217}
218EXPORT_SYMBOL_GPL(is_dock_device);
219
220/**
221 * dock_present - see if the dock station is present.
222 * @ds: the dock station
223 *
224 * execute the _STA method. note that present does not
225 * imply that we are docked.
226 */
227static int dock_present(struct dock_station *ds)
228{
229 unsigned long long sta;
230 acpi_status status;
231
232 if (ds) {
233 status = acpi_evaluate_integer(ds->handle, "_STA", NULL, &sta);
234 if (ACPI_SUCCESS(status) && sta)
235 return 1;
236 }
237 return 0;
238}
239
240/**
241 * hot_remove_dock_devices - Remove dock station devices.
242 * @ds: Dock station.
243 */
244static void hot_remove_dock_devices(struct dock_station *ds)
245{
246 struct dock_dependent_device *dd;
247
248 /*
249 * Walk the list in reverse order so that devices that have been added
250 * last are removed first (in case there are some indirect dependencies
251 * between them).
252 */
253 list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
254 dock_hotplug_event(dd, ACPI_NOTIFY_EJECT_REQUEST, false);
255
256 list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
257 acpi_bus_trim(dd->adev);
258}
259
260/**
261 * hotplug_dock_devices - Insert devices on a dock station.
262 * @ds: the dock station
263 * @event: either bus check or device check request
264 *
265 * Some devices on the dock station need to have drivers called
266 * to perform hotplug operations after a dock event has occurred.
267 * Traverse the list of dock devices that have registered a
268 * hotplug handler, and call the handler.
269 */
270static void hotplug_dock_devices(struct dock_station *ds, u32 event)
271{
272 struct dock_dependent_device *dd;
273
274 /* Call driver specific post-dock fixups. */
275 list_for_each_entry(dd, &ds->dependent_devices, list)
276 dock_hotplug_event(dd, event, DOCK_CALL_FIXUP);
277
278 /* Call driver specific hotplug functions. */
279 list_for_each_entry(dd, &ds->dependent_devices, list)
280 dock_hotplug_event(dd, event, DOCK_CALL_HANDLER);
281
282 /*
283 * Check if all devices have been enumerated already. If not, run
284 * acpi_bus_scan() for them and that will cause scan handlers to be
285 * attached to device objects or acpi_drivers to be stopped/started if
286 * they are present.
287 */
288 list_for_each_entry(dd, &ds->dependent_devices, list) {
289 struct acpi_device *adev = dd->adev;
290
291 if (!acpi_device_enumerated(adev)) {
292 int ret = acpi_bus_scan(adev->handle);
293 if (ret)
294 dev_dbg(&adev->dev, "scan error %d\n", -ret);
295 }
296 }
297}
298
299static void dock_event(struct dock_station *ds, u32 event, int num)
300{
301 struct device *dev = &ds->dock_device->dev;
302 char event_string[13];
303 char *envp[] = { event_string, NULL };
304 struct dock_dependent_device *dd;
305
306 if (num == UNDOCK_EVENT)
307 sprintf(event_string, "EVENT=undock");
308 else
309 sprintf(event_string, "EVENT=dock");
310
311 /*
312 * Indicate that the status of the dock station has
313 * changed.
314 */
315 if (num == DOCK_EVENT)
316 kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
317
318 list_for_each_entry(dd, &ds->dependent_devices, list)
319 dock_hotplug_event(dd, event, DOCK_CALL_UEVENT);
320
321 if (num != DOCK_EVENT)
322 kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
323}
324
325/**
326 * handle_dock - handle a dock event
327 * @ds: the dock station
328 * @dock: to dock, or undock - that is the question
329 *
330 * Execute the _DCK method in response to an acpi event
331 */
332static void handle_dock(struct dock_station *ds, int dock)
333{
334 acpi_status status;
335 struct acpi_object_list arg_list;
336 union acpi_object arg;
337 unsigned long long value;
338
339 acpi_handle_info(ds->handle, "%s\n", dock ? "docking" : "undocking");
340
341 /* _DCK method has one argument */
342 arg_list.count = 1;
343 arg_list.pointer = &arg;
344 arg.type = ACPI_TYPE_INTEGER;
345 arg.integer.value = dock;
346 status = acpi_evaluate_integer(ds->handle, "_DCK", &arg_list, &value);
347 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
348 acpi_handle_err(ds->handle, "Failed to execute _DCK (0x%x)\n",
349 status);
350}
351
352static inline void dock(struct dock_station *ds)
353{
354 handle_dock(ds, 1);
355}
356
357static inline void undock(struct dock_station *ds)
358{
359 handle_dock(ds, 0);
360}
361
362static inline void begin_dock(struct dock_station *ds)
363{
364 ds->flags |= DOCK_DOCKING;
365}
366
367static inline void complete_dock(struct dock_station *ds)
368{
369 ds->flags &= ~(DOCK_DOCKING);
370 ds->last_dock_time = jiffies;
371}
372
373static inline void begin_undock(struct dock_station *ds)
374{
375 ds->flags |= DOCK_UNDOCKING;
376}
377
378static inline void complete_undock(struct dock_station *ds)
379{
380 ds->flags &= ~(DOCK_UNDOCKING);
381}
382
383/**
384 * dock_in_progress - see if we are in the middle of handling a dock event
385 * @ds: the dock station
386 *
387 * Sometimes while docking, false dock events can be sent to the driver
388 * because good connections aren't made or some other reason. Ignore these
389 * if we are in the middle of doing something.
390 */
391static int dock_in_progress(struct dock_station *ds)
392{
393 if ((ds->flags & DOCK_DOCKING) ||
394 time_before(jiffies, (ds->last_dock_time + HZ)))
395 return 1;
396 return 0;
397}
398
399/**
400 * handle_eject_request - handle an undock request checking for error conditions
401 *
402 * Check to make sure the dock device is still present, then undock and
403 * hotremove all the devices that may need removing.
404 */
405static int handle_eject_request(struct dock_station *ds, u32 event)
406{
407 if (dock_in_progress(ds))
408 return -EBUSY;
409
410 /*
411 * here we need to generate the undock
412 * event prior to actually doing the undock
413 * so that the device struct still exists.
414 * Also, even send the dock event if the
415 * device is not present anymore
416 */
417 dock_event(ds, event, UNDOCK_EVENT);
418
419 hot_remove_dock_devices(ds);
420 undock(ds);
421 acpi_evaluate_lck(ds->handle, 0);
422 acpi_evaluate_ej0(ds->handle);
423 if (dock_present(ds)) {
424 acpi_handle_err(ds->handle, "Unable to undock!\n");
425 return -EBUSY;
426 }
427 complete_undock(ds);
428 return 0;
429}
430
431/**
432 * dock_notify - Handle ACPI dock notification.
433 * @adev: Dock station's ACPI device object.
434 * @event: Event code.
435 *
436 * If we are notified to dock, then check to see if the dock is
437 * present and then dock. Notify all drivers of the dock event,
438 * and then hotplug and devices that may need hotplugging.
439 */
440int dock_notify(struct acpi_device *adev, u32 event)
441{
442 acpi_handle handle = adev->handle;
443 struct dock_station *ds = find_dock_station(handle);
444 int surprise_removal = 0;
445
446 if (!ds)
447 return -ENODEV;
448
449 /*
450 * According to acpi spec 3.0a, if a DEVICE_CHECK notification
451 * is sent and _DCK is present, it is assumed to mean an undock
452 * request.
453 */
454 if ((ds->flags & DOCK_IS_DOCK) && event == ACPI_NOTIFY_DEVICE_CHECK)
455 event = ACPI_NOTIFY_EJECT_REQUEST;
456
457 /*
458 * dock station: BUS_CHECK - docked or surprise removal
459 * DEVICE_CHECK - undocked
460 * other device: BUS_CHECK/DEVICE_CHECK - added or surprise removal
461 *
462 * To simplify event handling, dock dependent device handler always
463 * get ACPI_NOTIFY_BUS_CHECK/ACPI_NOTIFY_DEVICE_CHECK for add and
464 * ACPI_NOTIFY_EJECT_REQUEST for removal
465 */
466 switch (event) {
467 case ACPI_NOTIFY_BUS_CHECK:
468 case ACPI_NOTIFY_DEVICE_CHECK:
469 if (!dock_in_progress(ds) && !acpi_device_enumerated(adev)) {
470 begin_dock(ds);
471 dock(ds);
472 if (!dock_present(ds)) {
473 acpi_handle_err(handle, "Unable to dock!\n");
474 complete_dock(ds);
475 break;
476 }
477 hotplug_dock_devices(ds, event);
478 complete_dock(ds);
479 dock_event(ds, event, DOCK_EVENT);
480 acpi_evaluate_lck(ds->handle, 1);
481 acpi_update_all_gpes();
482 break;
483 }
484 if (dock_present(ds) || dock_in_progress(ds))
485 break;
486 /* This is a surprise removal */
487 surprise_removal = 1;
488 event = ACPI_NOTIFY_EJECT_REQUEST;
489 /* Fall back */
490 case ACPI_NOTIFY_EJECT_REQUEST:
491 begin_undock(ds);
492 if ((immediate_undock && !(ds->flags & DOCK_IS_ATA))
493 || surprise_removal)
494 handle_eject_request(ds, event);
495 else
496 dock_event(ds, event, UNDOCK_EVENT);
497 break;
498 }
499 return 0;
500}
501
502/*
503 * show_docked - read method for "docked" file in sysfs
504 */
505static ssize_t show_docked(struct device *dev,
506 struct device_attribute *attr, char *buf)
507{
508 struct dock_station *dock_station = dev->platform_data;
509 struct acpi_device *adev = NULL;
510
511 acpi_bus_get_device(dock_station->handle, &adev);
512 return snprintf(buf, PAGE_SIZE, "%u\n", acpi_device_enumerated(adev));
513}
514static DEVICE_ATTR(docked, S_IRUGO, show_docked, NULL);
515
516/*
517 * show_flags - read method for flags file in sysfs
518 */
519static ssize_t show_flags(struct device *dev,
520 struct device_attribute *attr, char *buf)
521{
522 struct dock_station *dock_station = dev->platform_data;
523 return snprintf(buf, PAGE_SIZE, "%d\n", dock_station->flags);
524
525}
526static DEVICE_ATTR(flags, S_IRUGO, show_flags, NULL);
527
528/*
529 * write_undock - write method for "undock" file in sysfs
530 */
531static ssize_t write_undock(struct device *dev, struct device_attribute *attr,
532 const char *buf, size_t count)
533{
534 int ret;
535 struct dock_station *dock_station = dev->platform_data;
536
537 if (!count)
538 return -EINVAL;
539
540 acpi_scan_lock_acquire();
541 begin_undock(dock_station);
542 ret = handle_eject_request(dock_station, ACPI_NOTIFY_EJECT_REQUEST);
543 acpi_scan_lock_release();
544 return ret ? ret: count;
545}
546static DEVICE_ATTR(undock, S_IWUSR, NULL, write_undock);
547
548/*
549 * show_dock_uid - read method for "uid" file in sysfs
550 */
551static ssize_t show_dock_uid(struct device *dev,
552 struct device_attribute *attr, char *buf)
553{
554 unsigned long long lbuf;
555 struct dock_station *dock_station = dev->platform_data;
556 acpi_status status = acpi_evaluate_integer(dock_station->handle,
557 "_UID", NULL, &lbuf);
558 if (ACPI_FAILURE(status))
559 return 0;
560
561 return snprintf(buf, PAGE_SIZE, "%llx\n", lbuf);
562}
563static DEVICE_ATTR(uid, S_IRUGO, show_dock_uid, NULL);
564
565static ssize_t show_dock_type(struct device *dev,
566 struct device_attribute *attr, char *buf)
567{
568 struct dock_station *dock_station = dev->platform_data;
569 char *type;
570
571 if (dock_station->flags & DOCK_IS_DOCK)
572 type = "dock_station";
573 else if (dock_station->flags & DOCK_IS_ATA)
574 type = "ata_bay";
575 else if (dock_station->flags & DOCK_IS_BAT)
576 type = "battery_bay";
577 else
578 type = "unknown";
579
580 return snprintf(buf, PAGE_SIZE, "%s\n", type);
581}
582static DEVICE_ATTR(type, S_IRUGO, show_dock_type, NULL);
583
584static struct attribute *dock_attributes[] = {
585 &dev_attr_docked.attr,
586 &dev_attr_flags.attr,
587 &dev_attr_undock.attr,
588 &dev_attr_uid.attr,
589 &dev_attr_type.attr,
590 NULL
591};
592
593static struct attribute_group dock_attribute_group = {
594 .attrs = dock_attributes
595};
596
597/**
598 * acpi_dock_add - Add a new dock station
599 * @adev: Dock station ACPI device object.
600 *
601 * allocated and initialize a new dock station device.
602 */
603void acpi_dock_add(struct acpi_device *adev)
604{
605 struct dock_station *dock_station, ds = { NULL, };
606 struct platform_device_info pdevinfo;
607 acpi_handle handle = adev->handle;
608 struct platform_device *dd;
609 int ret;
610
611 memset(&pdevinfo, 0, sizeof(pdevinfo));
612 pdevinfo.name = "dock";
613 pdevinfo.id = dock_station_count;
614 pdevinfo.fwnode = acpi_fwnode_handle(adev);
615 pdevinfo.data = &ds;
616 pdevinfo.size_data = sizeof(ds);
617 dd = platform_device_register_full(&pdevinfo);
618 if (IS_ERR(dd))
619 return;
620
621 dock_station = dd->dev.platform_data;
622
623 dock_station->handle = handle;
624 dock_station->dock_device = dd;
625 dock_station->last_dock_time = jiffies - HZ;
626
627 INIT_LIST_HEAD(&dock_station->sibling);
628 INIT_LIST_HEAD(&dock_station->dependent_devices);
629
630 /* we want the dock device to send uevents */
631 dev_set_uevent_suppress(&dd->dev, 0);
632
633 if (acpi_dock_match(handle))
634 dock_station->flags |= DOCK_IS_DOCK;
635 if (acpi_ata_match(handle))
636 dock_station->flags |= DOCK_IS_ATA;
637 if (acpi_device_is_battery(adev))
638 dock_station->flags |= DOCK_IS_BAT;
639
640 ret = sysfs_create_group(&dd->dev.kobj, &dock_attribute_group);
641 if (ret)
642 goto err_unregister;
643
644 /* add the dock station as a device dependent on itself */
645 ret = add_dock_dependent_device(dock_station, adev);
646 if (ret)
647 goto err_rmgroup;
648
649 dock_station_count++;
650 list_add(&dock_station->sibling, &dock_stations);
651 adev->flags.is_dock_station = true;
652 dev_info(&adev->dev, "ACPI dock station (docks/bays count: %d)\n",
653 dock_station_count);
654 return;
655
656err_rmgroup:
657 sysfs_remove_group(&dd->dev.kobj, &dock_attribute_group);
658
659err_unregister:
660 platform_device_unregister(dd);
661 acpi_handle_err(handle, "%s encountered error %d\n", __func__, ret);
662}