2 * dock.c - ACPI dock station driver
4 * Copyright (C) 2006 Kristen Carlson Accardi <kristen.c.accardi@intel.com>
6 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or (at
11 * your option) any later version.
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/slab.h>
28 #include <linux/init.h>
29 #include <linux/types.h>
30 #include <linux/notifier.h>
31 #include <linux/platform_device.h>
32 #include <linux/jiffies.h>
33 #include <linux/stddef.h>
34 #include <linux/acpi.h>
36 #define PREFIX "ACPI: "
38 #define ACPI_DOCK_DRIVER_DESCRIPTION "ACPI Dock Station Driver"
40 ACPI_MODULE_NAME("dock");
41 MODULE_AUTHOR("Kristen Carlson Accardi");
42 MODULE_DESCRIPTION(ACPI_DOCK_DRIVER_DESCRIPTION);
43 MODULE_LICENSE("GPL");
45 static bool immediate_undock = 1;
46 module_param(immediate_undock, bool, 0644);
47 MODULE_PARM_DESC(immediate_undock, "1 (default) will cause the driver to "
48 "undock immediately when the undock button is pressed, 0 will cause"
49 " the driver to wait for userspace to write the undock sysfs file "
52 static const struct acpi_device_id dock_device_ids[] = {
56 MODULE_DEVICE_TABLE(acpi, dock_device_ids);
60 unsigned long last_dock_time;
62 struct list_head dependent_devices;
64 struct list_head sibling;
65 struct platform_device *dock_device;
67 static LIST_HEAD(dock_stations);
68 static int dock_station_count;
69 static DEFINE_MUTEX(hotplug_lock);
71 struct dock_dependent_device {
72 struct list_head list;
74 const struct acpi_dock_ops *hp_ops;
76 unsigned int hp_refcount;
77 void (*hp_release)(void *);
80 #define DOCK_DOCKING 0x00000001
81 #define DOCK_UNDOCKING 0x00000002
82 #define DOCK_IS_DOCK 0x00000010
83 #define DOCK_IS_ATA 0x00000020
84 #define DOCK_IS_BAT 0x00000040
86 #define UNDOCK_EVENT 2
88 enum dock_callback_type {
94 /*****************************************************************************
95 * Dock Dependent device functions *
96 *****************************************************************************/
98 * add_dock_dependent_device - associate a device with the dock station
99 * @ds: The dock station
100 * @handle: handle of the dependent device
102 * Add the dependent device to the dock's dependent device list.
105 add_dock_dependent_device(struct dock_station *ds, acpi_handle handle)
107 struct dock_dependent_device *dd;
109 dd = kzalloc(sizeof(*dd), GFP_KERNEL);
114 INIT_LIST_HEAD(&dd->list);
115 list_add_tail(&dd->list, &ds->dependent_devices);
120 static void remove_dock_dependent_devices(struct dock_station *ds)
122 struct dock_dependent_device *dd, *aux;
124 list_for_each_entry_safe(dd, aux, &ds->dependent_devices, list) {
131 * dock_init_hotplug - Initialize a hotplug device on a docking station.
132 * @dd: Dock-dependent device.
133 * @ops: Dock operations to attach to the dependent device.
134 * @context: Data to pass to the @ops callbacks and @release.
135 * @init: Optional initialization routine to run after setting up context.
136 * @release: Optional release routine to run on removal.
138 static int dock_init_hotplug(struct dock_dependent_device *dd,
139 const struct acpi_dock_ops *ops, void *context,
140 void (*init)(void *), void (*release)(void *))
144 mutex_lock(&hotplug_lock);
145 if (WARN_ON(dd->hp_context)) {
150 dd->hp_context = context;
151 dd->hp_release = release;
155 mutex_unlock(&hotplug_lock);
160 * dock_release_hotplug - Decrement hotplug reference counter of dock device.
161 * @dd: Dock-dependent device.
163 * Decrement the reference counter of @dd and if 0, detach its hotplug
164 * operations from it, reset its context pointer and run the optional release
165 * routine if present.
167 static void dock_release_hotplug(struct dock_dependent_device *dd)
169 mutex_lock(&hotplug_lock);
170 if (dd->hp_context && !--dd->hp_refcount) {
171 void (*release)(void *) = dd->hp_release;
172 void *context = dd->hp_context;
175 dd->hp_context = NULL;
176 dd->hp_release = NULL;
180 mutex_unlock(&hotplug_lock);
183 static void dock_hotplug_event(struct dock_dependent_device *dd, u32 event,
184 enum dock_callback_type cb_type)
186 acpi_notify_handler cb = NULL;
189 mutex_lock(&hotplug_lock);
191 if (dd->hp_context) {
196 case DOCK_CALL_FIXUP:
197 cb = dd->hp_ops->fixup;
199 case DOCK_CALL_UEVENT:
200 cb = dd->hp_ops->uevent;
203 cb = dd->hp_ops->handler;
208 mutex_unlock(&hotplug_lock);
214 cb(dd->handle, event, dd->hp_context);
216 dock_release_hotplug(dd);
220 * find_dock_dependent_device - get a device dependent on this dock
221 * @ds: the dock station
222 * @handle: the acpi_handle of the device we want
224 * iterate over the dependent device list for this dock. If the
225 * dependent device matches the handle, return.
227 static struct dock_dependent_device *
228 find_dock_dependent_device(struct dock_station *ds, acpi_handle handle)
230 struct dock_dependent_device *dd;
232 list_for_each_entry(dd, &ds->dependent_devices, list)
233 if (handle == dd->handle)
239 /*****************************************************************************
241 *****************************************************************************/
242 static int __init is_battery(acpi_handle handle)
244 struct acpi_device_info *info;
247 if (!ACPI_SUCCESS(acpi_get_object_info(handle, &info)))
249 if (!(info->valid & ACPI_VALID_HID))
252 ret = !strcmp("PNP0C0A", info->hardware_id.string);
258 /* Check whether ACPI object is an ejectable battery or disk bay */
259 static bool __init is_ejectable_bay(acpi_handle handle)
261 if (acpi_has_method(handle, "_EJ0") && is_battery(handle))
264 return acpi_bay_match(handle);
268 * is_dock_device - see if a device is on a dock station
269 * @handle: acpi handle of the device
271 * If this device is either the dock station itself,
272 * or is a device dependent on the dock station, then it
275 int is_dock_device(acpi_handle handle)
277 struct dock_station *dock_station;
279 if (!dock_station_count)
282 if (acpi_dock_match(handle))
285 list_for_each_entry(dock_station, &dock_stations, sibling)
286 if (find_dock_dependent_device(dock_station, handle))
291 EXPORT_SYMBOL_GPL(is_dock_device);
294 * dock_present - see if the dock station is present.
295 * @ds: the dock station
297 * execute the _STA method. note that present does not
298 * imply that we are docked.
300 static int dock_present(struct dock_station *ds)
302 unsigned long long sta;
306 status = acpi_evaluate_integer(ds->handle, "_STA", NULL, &sta);
307 if (ACPI_SUCCESS(status) && sta)
314 * dock_create_acpi_device - add new devices to acpi
315 * @handle - handle of the device to add
317 * This function will create a new acpi_device for the given
318 * handle if one does not exist already. This should cause
319 * acpi to scan for drivers for the given devices, and call
320 * matching driver's add routine.
322 static void dock_create_acpi_device(acpi_handle handle)
324 struct acpi_device *device;
327 if (acpi_bus_get_device(handle, &device)) {
329 * no device created for this object,
330 * so we should create one.
332 ret = acpi_bus_scan(handle);
334 pr_debug("error adding bus, %x\n", -ret);
339 * dock_remove_acpi_device - remove the acpi_device struct from acpi
340 * @handle - the handle of the device to remove
342 * Tell acpi to remove the acpi_device. This should cause any loaded
343 * driver to have it's remove routine called.
345 static void dock_remove_acpi_device(acpi_handle handle)
347 struct acpi_device *device;
349 if (!acpi_bus_get_device(handle, &device))
350 acpi_bus_trim(device);
354 * hot_remove_dock_devices - Remove dock station devices.
357 static void hot_remove_dock_devices(struct dock_station *ds)
359 struct dock_dependent_device *dd;
362 * Walk the list in reverse order so that devices that have been added
363 * last are removed first (in case there are some indirect dependencies
366 list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
367 dock_hotplug_event(dd, ACPI_NOTIFY_EJECT_REQUEST, false);
369 list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
370 dock_remove_acpi_device(dd->handle);
374 * hotplug_dock_devices - Insert devices on a dock station.
375 * @ds: the dock station
376 * @event: either bus check or device check request
378 * Some devices on the dock station need to have drivers called
379 * to perform hotplug operations after a dock event has occurred.
380 * Traverse the list of dock devices that have registered a
381 * hotplug handler, and call the handler.
383 static void hotplug_dock_devices(struct dock_station *ds, u32 event)
385 struct dock_dependent_device *dd;
387 /* Call driver specific post-dock fixups. */
388 list_for_each_entry(dd, &ds->dependent_devices, list)
389 dock_hotplug_event(dd, event, DOCK_CALL_FIXUP);
391 /* Call driver specific hotplug functions. */
392 list_for_each_entry(dd, &ds->dependent_devices, list)
393 dock_hotplug_event(dd, event, DOCK_CALL_HANDLER);
396 * Now make sure that an acpi_device is created for each dependent
397 * device. That will cause scan handlers to be attached to device
398 * objects or acpi_drivers to be stopped/started if they are present.
400 list_for_each_entry(dd, &ds->dependent_devices, list)
401 dock_create_acpi_device(dd->handle);
404 static void dock_event(struct dock_station *ds, u32 event, int num)
406 struct device *dev = &ds->dock_device->dev;
407 char event_string[13];
408 char *envp[] = { event_string, NULL };
409 struct dock_dependent_device *dd;
411 if (num == UNDOCK_EVENT)
412 sprintf(event_string, "EVENT=undock");
414 sprintf(event_string, "EVENT=dock");
417 * Indicate that the status of the dock station has
420 if (num == DOCK_EVENT)
421 kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
423 list_for_each_entry(dd, &ds->dependent_devices, list)
424 dock_hotplug_event(dd, event, DOCK_CALL_UEVENT);
426 if (num != DOCK_EVENT)
427 kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
431 * handle_dock - handle a dock event
432 * @ds: the dock station
433 * @dock: to dock, or undock - that is the question
435 * Execute the _DCK method in response to an acpi event
437 static void handle_dock(struct dock_station *ds, int dock)
440 struct acpi_object_list arg_list;
441 union acpi_object arg;
442 unsigned long long value;
444 acpi_handle_info(ds->handle, "%s\n", dock ? "docking" : "undocking");
446 /* _DCK method has one argument */
448 arg_list.pointer = &arg;
449 arg.type = ACPI_TYPE_INTEGER;
450 arg.integer.value = dock;
451 status = acpi_evaluate_integer(ds->handle, "_DCK", &arg_list, &value);
452 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
453 acpi_handle_err(ds->handle, "Failed to execute _DCK (0x%x)\n",
457 static inline void dock(struct dock_station *ds)
462 static inline void undock(struct dock_station *ds)
467 static inline void begin_dock(struct dock_station *ds)
469 ds->flags |= DOCK_DOCKING;
472 static inline void complete_dock(struct dock_station *ds)
474 ds->flags &= ~(DOCK_DOCKING);
475 ds->last_dock_time = jiffies;
478 static inline void begin_undock(struct dock_station *ds)
480 ds->flags |= DOCK_UNDOCKING;
483 static inline void complete_undock(struct dock_station *ds)
485 ds->flags &= ~(DOCK_UNDOCKING);
489 * dock_in_progress - see if we are in the middle of handling a dock event
490 * @ds: the dock station
492 * Sometimes while docking, false dock events can be sent to the driver
493 * because good connections aren't made or some other reason. Ignore these
494 * if we are in the middle of doing something.
496 static int dock_in_progress(struct dock_station *ds)
498 if ((ds->flags & DOCK_DOCKING) ||
499 time_before(jiffies, (ds->last_dock_time + HZ)))
505 * register_hotplug_dock_device - register a hotplug function
506 * @handle: the handle of the device
507 * @ops: handlers to call after docking
508 * @context: device specific data
509 * @init: Optional initialization routine to run after registration
510 * @release: Optional release routine to run on unregistration
512 * If a driver would like to perform a hotplug operation after a dock
513 * event, they can register an acpi_notifiy_handler to be called by
514 * the dock driver after _DCK is executed.
516 int register_hotplug_dock_device(acpi_handle handle,
517 const struct acpi_dock_ops *ops, void *context,
518 void (*init)(void *), void (*release)(void *))
520 struct dock_dependent_device *dd;
521 struct dock_station *dock_station;
524 if (WARN_ON(!context))
527 if (!dock_station_count)
531 * make sure this handle is for a device dependent on the dock,
532 * this would include the dock station itself
534 list_for_each_entry(dock_station, &dock_stations, sibling) {
536 * An ATA bay can be in a dock and itself can be ejected
537 * separately, so there are two 'dock stations' which need the
540 dd = find_dock_dependent_device(dock_station, handle);
541 if (dd && !dock_init_hotplug(dd, ops, context, init, release))
547 EXPORT_SYMBOL_GPL(register_hotplug_dock_device);
550 * unregister_hotplug_dock_device - remove yourself from the hotplug list
551 * @handle: the acpi handle of the device
553 void unregister_hotplug_dock_device(acpi_handle handle)
555 struct dock_dependent_device *dd;
556 struct dock_station *dock_station;
558 if (!dock_station_count)
561 list_for_each_entry(dock_station, &dock_stations, sibling) {
562 dd = find_dock_dependent_device(dock_station, handle);
564 dock_release_hotplug(dd);
567 EXPORT_SYMBOL_GPL(unregister_hotplug_dock_device);
570 * handle_eject_request - handle an undock request checking for error conditions
572 * Check to make sure the dock device is still present, then undock and
573 * hotremove all the devices that may need removing.
575 static int handle_eject_request(struct dock_station *ds, u32 event)
577 if (dock_in_progress(ds))
581 * here we need to generate the undock
582 * event prior to actually doing the undock
583 * so that the device struct still exists.
584 * Also, even send the dock event if the
585 * device is not present anymore
587 dock_event(ds, event, UNDOCK_EVENT);
589 hot_remove_dock_devices(ds);
591 acpi_evaluate_lck(ds->handle, 0);
592 acpi_evaluate_ej0(ds->handle);
593 if (dock_present(ds)) {
594 acpi_handle_err(ds->handle, "Unable to undock!\n");
602 * dock_notify - act upon an acpi dock notification
604 * @event: the acpi event
606 * If we are notified to dock, then check to see if the dock is
607 * present and then dock. Notify all drivers of the dock event,
608 * and then hotplug and devices that may need hotplugging.
610 static void dock_notify(struct dock_station *ds, u32 event)
612 acpi_handle handle = ds->handle;
613 struct acpi_device *ad;
614 int surprise_removal = 0;
617 * According to acpi spec 3.0a, if a DEVICE_CHECK notification
618 * is sent and _DCK is present, it is assumed to mean an undock
621 if ((ds->flags & DOCK_IS_DOCK) && event == ACPI_NOTIFY_DEVICE_CHECK)
622 event = ACPI_NOTIFY_EJECT_REQUEST;
625 * dock station: BUS_CHECK - docked or surprise removal
626 * DEVICE_CHECK - undocked
627 * other device: BUS_CHECK/DEVICE_CHECK - added or surprise removal
629 * To simplify event handling, dock dependent device handler always
630 * get ACPI_NOTIFY_BUS_CHECK/ACPI_NOTIFY_DEVICE_CHECK for add and
631 * ACPI_NOTIFY_EJECT_REQUEST for removal
634 case ACPI_NOTIFY_BUS_CHECK:
635 case ACPI_NOTIFY_DEVICE_CHECK:
636 if (!dock_in_progress(ds) && acpi_bus_get_device(handle, &ad)) {
639 if (!dock_present(ds)) {
640 acpi_handle_err(handle, "Unable to dock!\n");
644 hotplug_dock_devices(ds, event);
646 dock_event(ds, event, DOCK_EVENT);
647 acpi_evaluate_lck(ds->handle, 1);
648 acpi_update_all_gpes();
651 if (dock_present(ds) || dock_in_progress(ds))
653 /* This is a surprise removal */
654 surprise_removal = 1;
655 event = ACPI_NOTIFY_EJECT_REQUEST;
657 case ACPI_NOTIFY_EJECT_REQUEST:
659 if ((immediate_undock && !(ds->flags & DOCK_IS_ATA))
661 handle_eject_request(ds, event);
663 dock_event(ds, event, UNDOCK_EVENT);
666 acpi_handle_err(handle, "Unknown dock event %d\n", event);
670 static void acpi_dock_deferred_cb(void *data, u32 event)
672 acpi_scan_lock_acquire();
673 dock_notify(data, event);
674 acpi_scan_lock_release();
677 static void dock_notify_handler(acpi_handle handle, u32 event, void *data)
679 if (event != ACPI_NOTIFY_BUS_CHECK && event != ACPI_NOTIFY_DEVICE_CHECK
680 && event != ACPI_NOTIFY_EJECT_REQUEST)
683 acpi_hotplug_execute(acpi_dock_deferred_cb, data, event);
687 * find_dock_devices - find devices on the dock station
688 * @handle: the handle of the device we are examining
690 * @context: the dock station private data
693 * This function is called by acpi_walk_namespace. It will
694 * check to see if an object has an _EJD method. If it does, then it
695 * will see if it is dependent on the dock station.
697 static acpi_status __init find_dock_devices(acpi_handle handle, u32 lvl,
698 void *context, void **rv)
700 struct dock_station *ds = context;
701 acpi_handle ejd = NULL;
703 acpi_bus_get_ejd(handle, &ejd);
704 if (ejd == ds->handle)
705 add_dock_dependent_device(ds, handle);
711 * show_docked - read method for "docked" file in sysfs
713 static ssize_t show_docked(struct device *dev,
714 struct device_attribute *attr, char *buf)
716 struct acpi_device *tmp;
718 struct dock_station *dock_station = dev->platform_data;
720 if (!acpi_bus_get_device(dock_station->handle, &tmp))
721 return snprintf(buf, PAGE_SIZE, "1\n");
722 return snprintf(buf, PAGE_SIZE, "0\n");
724 static DEVICE_ATTR(docked, S_IRUGO, show_docked, NULL);
727 * show_flags - read method for flags file in sysfs
729 static ssize_t show_flags(struct device *dev,
730 struct device_attribute *attr, char *buf)
732 struct dock_station *dock_station = dev->platform_data;
733 return snprintf(buf, PAGE_SIZE, "%d\n", dock_station->flags);
736 static DEVICE_ATTR(flags, S_IRUGO, show_flags, NULL);
739 * write_undock - write method for "undock" file in sysfs
741 static ssize_t write_undock(struct device *dev, struct device_attribute *attr,
742 const char *buf, size_t count)
745 struct dock_station *dock_station = dev->platform_data;
750 acpi_scan_lock_acquire();
751 begin_undock(dock_station);
752 ret = handle_eject_request(dock_station, ACPI_NOTIFY_EJECT_REQUEST);
753 acpi_scan_lock_release();
754 return ret ? ret: count;
756 static DEVICE_ATTR(undock, S_IWUSR, NULL, write_undock);
759 * show_dock_uid - read method for "uid" file in sysfs
761 static ssize_t show_dock_uid(struct device *dev,
762 struct device_attribute *attr, char *buf)
764 unsigned long long lbuf;
765 struct dock_station *dock_station = dev->platform_data;
766 acpi_status status = acpi_evaluate_integer(dock_station->handle,
767 "_UID", NULL, &lbuf);
768 if (ACPI_FAILURE(status))
771 return snprintf(buf, PAGE_SIZE, "%llx\n", lbuf);
773 static DEVICE_ATTR(uid, S_IRUGO, show_dock_uid, NULL);
775 static ssize_t show_dock_type(struct device *dev,
776 struct device_attribute *attr, char *buf)
778 struct dock_station *dock_station = dev->platform_data;
781 if (dock_station->flags & DOCK_IS_DOCK)
782 type = "dock_station";
783 else if (dock_station->flags & DOCK_IS_ATA)
785 else if (dock_station->flags & DOCK_IS_BAT)
786 type = "battery_bay";
790 return snprintf(buf, PAGE_SIZE, "%s\n", type);
792 static DEVICE_ATTR(type, S_IRUGO, show_dock_type, NULL);
794 static struct attribute *dock_attributes[] = {
795 &dev_attr_docked.attr,
796 &dev_attr_flags.attr,
797 &dev_attr_undock.attr,
803 static struct attribute_group dock_attribute_group = {
804 .attrs = dock_attributes
808 * dock_add - add a new dock station
809 * @handle: the dock station handle
811 * allocated and initialize a new dock station device. Find all devices
812 * that are on the dock station, and register for dock event notifications.
814 static int __init dock_add(acpi_handle handle)
816 struct dock_station *dock_station, ds = { NULL, };
817 struct platform_device *dd;
821 dd = platform_device_register_data(NULL, "dock", dock_station_count,
826 dock_station = dd->dev.platform_data;
828 dock_station->handle = handle;
829 dock_station->dock_device = dd;
830 dock_station->last_dock_time = jiffies - HZ;
832 INIT_LIST_HEAD(&dock_station->sibling);
833 INIT_LIST_HEAD(&dock_station->dependent_devices);
835 /* we want the dock device to send uevents */
836 dev_set_uevent_suppress(&dd->dev, 0);
838 if (acpi_dock_match(handle))
839 dock_station->flags |= DOCK_IS_DOCK;
840 if (acpi_ata_match(handle))
841 dock_station->flags |= DOCK_IS_ATA;
842 if (is_battery(handle))
843 dock_station->flags |= DOCK_IS_BAT;
845 ret = sysfs_create_group(&dd->dev.kobj, &dock_attribute_group);
849 /* Find dependent devices */
850 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
851 ACPI_UINT32_MAX, find_dock_devices, NULL,
854 /* add the dock station as a device dependent on itself */
855 ret = add_dock_dependent_device(dock_station, handle);
859 status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
860 dock_notify_handler, dock_station);
861 if (ACPI_FAILURE(status)) {
866 dock_station_count++;
867 list_add(&dock_station->sibling, &dock_stations);
871 remove_dock_dependent_devices(dock_station);
872 sysfs_remove_group(&dd->dev.kobj, &dock_attribute_group);
874 platform_device_unregister(dd);
875 acpi_handle_err(handle, "%s encountered error %d\n", __func__, ret);
880 * find_dock_and_bay - look for dock stations and bays
881 * @handle: acpi handle of a device
886 * This is called by acpi_walk_namespace to look for dock stations and bays.
888 static acpi_status __init
889 find_dock_and_bay(acpi_handle handle, u32 lvl, void *context, void **rv)
891 if (acpi_dock_match(handle) || is_ejectable_bay(handle))
897 void __init acpi_dock_init(void)
902 /* look for dock stations and bays */
903 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
904 ACPI_UINT32_MAX, find_dock_and_bay, NULL, NULL, NULL);
906 if (!dock_station_count) {
907 pr_info(PREFIX "No dock devices found.\n");
911 pr_info(PREFIX "%s: %d docks/bays found\n",
912 ACPI_DOCK_DRIVER_DESCRIPTION, dock_station_count);