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>
38 #define PREFIX "ACPI: "
40 #define ACPI_DOCK_DRIVER_DESCRIPTION "ACPI Dock Station Driver"
42 ACPI_MODULE_NAME("dock");
43 MODULE_AUTHOR("Kristen Carlson Accardi");
44 MODULE_DESCRIPTION(ACPI_DOCK_DRIVER_DESCRIPTION);
45 MODULE_LICENSE("GPL");
47 static bool immediate_undock = 1;
48 module_param(immediate_undock, bool, 0644);
49 MODULE_PARM_DESC(immediate_undock, "1 (default) will cause the driver to "
50 "undock immediately when the undock button is pressed, 0 will cause"
51 " the driver to wait for userspace to write the undock sysfs file "
54 static const struct acpi_device_id dock_device_ids[] = {
58 MODULE_DEVICE_TABLE(acpi, dock_device_ids);
62 unsigned long last_dock_time;
64 struct list_head dependent_devices;
66 struct list_head sibling;
67 struct platform_device *dock_device;
69 static LIST_HEAD(dock_stations);
70 static int dock_station_count;
71 static DEFINE_MUTEX(hotplug_lock);
73 struct dock_dependent_device {
74 struct list_head list;
75 struct acpi_device *adev;
76 const struct acpi_dock_ops *hp_ops;
78 unsigned int hp_refcount;
79 void (*hp_release)(void *);
82 #define DOCK_DOCKING 0x00000001
83 #define DOCK_UNDOCKING 0x00000002
84 #define DOCK_IS_DOCK 0x00000010
85 #define DOCK_IS_ATA 0x00000020
86 #define DOCK_IS_BAT 0x00000040
88 #define UNDOCK_EVENT 2
90 enum dock_callback_type {
96 /*****************************************************************************
97 * Dock Dependent device functions *
98 *****************************************************************************/
100 * add_dock_dependent_device - associate a device with the dock station
102 * @adev: Dependent ACPI device object.
104 * Add the dependent device to the dock's dependent device list.
106 static int add_dock_dependent_device(struct dock_station *ds,
107 struct acpi_device *adev)
109 struct dock_dependent_device *dd;
111 dd = kzalloc(sizeof(*dd), GFP_KERNEL);
116 INIT_LIST_HEAD(&dd->list);
117 list_add_tail(&dd->list, &ds->dependent_devices);
122 static void remove_dock_dependent_devices(struct dock_station *ds)
124 struct dock_dependent_device *dd, *aux;
126 list_for_each_entry_safe(dd, aux, &ds->dependent_devices, list) {
133 * dock_init_hotplug - Initialize a hotplug device on a docking station.
134 * @dd: Dock-dependent device.
135 * @ops: Dock operations to attach to the dependent device.
136 * @context: Data to pass to the @ops callbacks and @release.
137 * @init: Optional initialization routine to run after setting up context.
138 * @release: Optional release routine to run on removal.
140 static int dock_init_hotplug(struct dock_dependent_device *dd,
141 const struct acpi_dock_ops *ops, void *context,
142 void (*init)(void *), void (*release)(void *))
146 mutex_lock(&hotplug_lock);
147 if (WARN_ON(dd->hp_context)) {
152 dd->hp_context = context;
153 dd->hp_release = release;
157 mutex_unlock(&hotplug_lock);
162 * dock_release_hotplug - Decrement hotplug reference counter of dock device.
163 * @dd: Dock-dependent device.
165 * Decrement the reference counter of @dd and if 0, detach its hotplug
166 * operations from it, reset its context pointer and run the optional release
167 * routine if present.
169 static void dock_release_hotplug(struct dock_dependent_device *dd)
171 mutex_lock(&hotplug_lock);
172 if (dd->hp_context && !--dd->hp_refcount) {
173 void (*release)(void *) = dd->hp_release;
174 void *context = dd->hp_context;
177 dd->hp_context = NULL;
178 dd->hp_release = NULL;
182 mutex_unlock(&hotplug_lock);
185 static void dock_hotplug_event(struct dock_dependent_device *dd, u32 event,
186 enum dock_callback_type cb_type)
188 struct acpi_device *adev = dd->adev;
189 acpi_notify_handler cb = NULL;
192 acpi_lock_hp_context();
197 if (cb_type == DOCK_CALL_FIXUP) {
198 void (*fixup)(struct acpi_device *);
200 fixup = adev->hp->fixup;
202 acpi_unlock_hp_context();
206 } else if (cb_type == DOCK_CALL_UEVENT) {
207 void (*uevent)(struct acpi_device *, u32);
209 uevent = adev->hp->uevent;
211 acpi_unlock_hp_context();
216 int (*notify)(struct acpi_device *, u32);
218 notify = adev->hp->notify;
220 acpi_unlock_hp_context();
227 acpi_unlock_hp_context();
229 mutex_lock(&hotplug_lock);
231 if (dd->hp_context) {
236 case DOCK_CALL_FIXUP:
237 cb = dd->hp_ops->fixup;
239 case DOCK_CALL_UEVENT:
240 cb = dd->hp_ops->uevent;
243 cb = dd->hp_ops->handler;
248 mutex_unlock(&hotplug_lock);
254 cb(dd->adev->handle, event, dd->hp_context);
256 dock_release_hotplug(dd);
259 static struct dock_station *find_dock_station(acpi_handle handle)
261 struct dock_station *ds;
263 list_for_each_entry(ds, &dock_stations, sibling)
264 if (ds->handle == handle)
271 * find_dock_dependent_device - get a device dependent on this dock
272 * @ds: the dock station
273 * @adev: ACPI device object to find.
275 * iterate over the dependent device list for this dock. If the
276 * dependent device matches the handle, return.
278 static struct dock_dependent_device *
279 find_dock_dependent_device(struct dock_station *ds, struct acpi_device *adev)
281 struct dock_dependent_device *dd;
283 list_for_each_entry(dd, &ds->dependent_devices, list)
284 if (adev == dd->adev)
290 void register_dock_dependent_device(struct acpi_device *adev,
291 acpi_handle dshandle)
293 struct dock_station *ds = find_dock_station(dshandle);
295 if (ds && !find_dock_dependent_device(ds, adev))
296 add_dock_dependent_device(ds, adev);
299 /*****************************************************************************
301 *****************************************************************************/
304 * is_dock_device - see if a device is on a dock station
305 * @adev: ACPI device object to check.
307 * If this device is either the dock station itself,
308 * or is a device dependent on the dock station, then it
311 int is_dock_device(struct acpi_device *adev)
313 struct dock_station *dock_station;
315 if (!dock_station_count)
318 if (acpi_dock_match(adev->handle))
321 list_for_each_entry(dock_station, &dock_stations, sibling)
322 if (find_dock_dependent_device(dock_station, adev))
327 EXPORT_SYMBOL_GPL(is_dock_device);
330 * dock_present - see if the dock station is present.
331 * @ds: the dock station
333 * execute the _STA method. note that present does not
334 * imply that we are docked.
336 static int dock_present(struct dock_station *ds)
338 unsigned long long sta;
342 status = acpi_evaluate_integer(ds->handle, "_STA", NULL, &sta);
343 if (ACPI_SUCCESS(status) && sta)
350 * hot_remove_dock_devices - Remove dock station devices.
353 static void hot_remove_dock_devices(struct dock_station *ds)
355 struct dock_dependent_device *dd;
358 * Walk the list in reverse order so that devices that have been added
359 * last are removed first (in case there are some indirect dependencies
362 list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
363 dock_hotplug_event(dd, ACPI_NOTIFY_EJECT_REQUEST, false);
365 list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
366 acpi_bus_trim(dd->adev);
370 * hotplug_dock_devices - Insert devices on a dock station.
371 * @ds: the dock station
372 * @event: either bus check or device check request
374 * Some devices on the dock station need to have drivers called
375 * to perform hotplug operations after a dock event has occurred.
376 * Traverse the list of dock devices that have registered a
377 * hotplug handler, and call the handler.
379 static void hotplug_dock_devices(struct dock_station *ds, u32 event)
381 struct dock_dependent_device *dd;
383 /* Call driver specific post-dock fixups. */
384 list_for_each_entry(dd, &ds->dependent_devices, list)
385 dock_hotplug_event(dd, event, DOCK_CALL_FIXUP);
387 /* Call driver specific hotplug functions. */
388 list_for_each_entry(dd, &ds->dependent_devices, list)
389 dock_hotplug_event(dd, event, DOCK_CALL_HANDLER);
392 * Check if all devices have been enumerated already. If not, run
393 * acpi_bus_scan() for them and that will cause scan handlers to be
394 * attached to device objects or acpi_drivers to be stopped/started if
397 list_for_each_entry(dd, &ds->dependent_devices, list) {
398 struct acpi_device *adev = dd->adev;
400 if (!acpi_device_enumerated(adev)) {
401 int ret = acpi_bus_scan(adev->handle);
403 dev_dbg(&adev->dev, "scan error %d\n", -ret);
408 static void dock_event(struct dock_station *ds, u32 event, int num)
410 struct device *dev = &ds->dock_device->dev;
411 char event_string[13];
412 char *envp[] = { event_string, NULL };
413 struct dock_dependent_device *dd;
415 if (num == UNDOCK_EVENT)
416 sprintf(event_string, "EVENT=undock");
418 sprintf(event_string, "EVENT=dock");
421 * Indicate that the status of the dock station has
424 if (num == DOCK_EVENT)
425 kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
427 list_for_each_entry(dd, &ds->dependent_devices, list)
428 dock_hotplug_event(dd, event, DOCK_CALL_UEVENT);
430 if (num != DOCK_EVENT)
431 kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
435 * handle_dock - handle a dock event
436 * @ds: the dock station
437 * @dock: to dock, or undock - that is the question
439 * Execute the _DCK method in response to an acpi event
441 static void handle_dock(struct dock_station *ds, int dock)
444 struct acpi_object_list arg_list;
445 union acpi_object arg;
446 unsigned long long value;
448 acpi_handle_info(ds->handle, "%s\n", dock ? "docking" : "undocking");
450 /* _DCK method has one argument */
452 arg_list.pointer = &arg;
453 arg.type = ACPI_TYPE_INTEGER;
454 arg.integer.value = dock;
455 status = acpi_evaluate_integer(ds->handle, "_DCK", &arg_list, &value);
456 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
457 acpi_handle_err(ds->handle, "Failed to execute _DCK (0x%x)\n",
461 static inline void dock(struct dock_station *ds)
466 static inline void undock(struct dock_station *ds)
471 static inline void begin_dock(struct dock_station *ds)
473 ds->flags |= DOCK_DOCKING;
476 static inline void complete_dock(struct dock_station *ds)
478 ds->flags &= ~(DOCK_DOCKING);
479 ds->last_dock_time = jiffies;
482 static inline void begin_undock(struct dock_station *ds)
484 ds->flags |= DOCK_UNDOCKING;
487 static inline void complete_undock(struct dock_station *ds)
489 ds->flags &= ~(DOCK_UNDOCKING);
493 * dock_in_progress - see if we are in the middle of handling a dock event
494 * @ds: the dock station
496 * Sometimes while docking, false dock events can be sent to the driver
497 * because good connections aren't made or some other reason. Ignore these
498 * if we are in the middle of doing something.
500 static int dock_in_progress(struct dock_station *ds)
502 if ((ds->flags & DOCK_DOCKING) ||
503 time_before(jiffies, (ds->last_dock_time + HZ)))
509 * register_hotplug_dock_device - register a hotplug function
510 * @handle: the handle of the device
511 * @ops: handlers to call after docking
512 * @context: device specific data
513 * @init: Optional initialization routine to run after registration
514 * @release: Optional release routine to run on unregistration
516 * If a driver would like to perform a hotplug operation after a dock
517 * event, they can register an acpi_notifiy_handler to be called by
518 * the dock driver after _DCK is executed.
520 int register_hotplug_dock_device(acpi_handle handle,
521 const struct acpi_dock_ops *ops, void *context,
522 void (*init)(void *), void (*release)(void *))
524 struct dock_dependent_device *dd;
525 struct dock_station *dock_station;
526 struct acpi_device *adev;
529 if (WARN_ON(!context))
532 if (!dock_station_count)
535 ret = acpi_bus_get_device(handle, &adev);
540 * make sure this handle is for a device dependent on the dock,
541 * this would include the dock station itself
543 list_for_each_entry(dock_station, &dock_stations, sibling) {
545 * An ATA bay can be in a dock and itself can be ejected
546 * separately, so there are two 'dock stations' which need the
549 dd = find_dock_dependent_device(dock_station, adev);
550 if (dd && !dock_init_hotplug(dd, ops, context, init, release))
556 EXPORT_SYMBOL_GPL(register_hotplug_dock_device);
559 * unregister_hotplug_dock_device - remove yourself from the hotplug list
560 * @handle: the acpi handle of the device
562 void unregister_hotplug_dock_device(acpi_handle handle)
564 struct dock_dependent_device *dd;
565 struct dock_station *dock_station;
566 struct acpi_device *adev;
568 if (!dock_station_count)
571 if (acpi_bus_get_device(handle, &adev))
574 list_for_each_entry(dock_station, &dock_stations, sibling) {
575 dd = find_dock_dependent_device(dock_station, adev);
577 dock_release_hotplug(dd);
580 EXPORT_SYMBOL_GPL(unregister_hotplug_dock_device);
583 * handle_eject_request - handle an undock request checking for error conditions
585 * Check to make sure the dock device is still present, then undock and
586 * hotremove all the devices that may need removing.
588 static int handle_eject_request(struct dock_station *ds, u32 event)
590 if (dock_in_progress(ds))
594 * here we need to generate the undock
595 * event prior to actually doing the undock
596 * so that the device struct still exists.
597 * Also, even send the dock event if the
598 * device is not present anymore
600 dock_event(ds, event, UNDOCK_EVENT);
602 hot_remove_dock_devices(ds);
604 acpi_evaluate_lck(ds->handle, 0);
605 acpi_evaluate_ej0(ds->handle);
606 if (dock_present(ds)) {
607 acpi_handle_err(ds->handle, "Unable to undock!\n");
615 * dock_notify - Handle ACPI dock notification.
616 * @adev: Dock station's ACPI device object.
617 * @event: Event code.
619 * If we are notified to dock, then check to see if the dock is
620 * present and then dock. Notify all drivers of the dock event,
621 * and then hotplug and devices that may need hotplugging.
623 int dock_notify(struct acpi_device *adev, u32 event)
625 acpi_handle handle = adev->handle;
626 struct dock_station *ds = find_dock_station(handle);
627 int surprise_removal = 0;
633 * According to acpi spec 3.0a, if a DEVICE_CHECK notification
634 * is sent and _DCK is present, it is assumed to mean an undock
637 if ((ds->flags & DOCK_IS_DOCK) && event == ACPI_NOTIFY_DEVICE_CHECK)
638 event = ACPI_NOTIFY_EJECT_REQUEST;
641 * dock station: BUS_CHECK - docked or surprise removal
642 * DEVICE_CHECK - undocked
643 * other device: BUS_CHECK/DEVICE_CHECK - added or surprise removal
645 * To simplify event handling, dock dependent device handler always
646 * get ACPI_NOTIFY_BUS_CHECK/ACPI_NOTIFY_DEVICE_CHECK for add and
647 * ACPI_NOTIFY_EJECT_REQUEST for removal
650 case ACPI_NOTIFY_BUS_CHECK:
651 case ACPI_NOTIFY_DEVICE_CHECK:
652 if (!dock_in_progress(ds) && !acpi_device_enumerated(adev)) {
655 if (!dock_present(ds)) {
656 acpi_handle_err(handle, "Unable to dock!\n");
660 hotplug_dock_devices(ds, event);
662 dock_event(ds, event, DOCK_EVENT);
663 acpi_evaluate_lck(ds->handle, 1);
664 acpi_update_all_gpes();
667 if (dock_present(ds) || dock_in_progress(ds))
669 /* This is a surprise removal */
670 surprise_removal = 1;
671 event = ACPI_NOTIFY_EJECT_REQUEST;
673 case ACPI_NOTIFY_EJECT_REQUEST:
675 if ((immediate_undock && !(ds->flags & DOCK_IS_ATA))
677 handle_eject_request(ds, event);
679 dock_event(ds, event, UNDOCK_EVENT);
686 * show_docked - read method for "docked" file in sysfs
688 static ssize_t show_docked(struct device *dev,
689 struct device_attribute *attr, char *buf)
691 struct dock_station *dock_station = dev->platform_data;
692 struct acpi_device *adev = NULL;
694 acpi_bus_get_device(dock_station->handle, &adev);
695 return snprintf(buf, PAGE_SIZE, "%u\n", acpi_device_enumerated(adev));
697 static DEVICE_ATTR(docked, S_IRUGO, show_docked, NULL);
700 * show_flags - read method for flags file in sysfs
702 static ssize_t show_flags(struct device *dev,
703 struct device_attribute *attr, char *buf)
705 struct dock_station *dock_station = dev->platform_data;
706 return snprintf(buf, PAGE_SIZE, "%d\n", dock_station->flags);
709 static DEVICE_ATTR(flags, S_IRUGO, show_flags, NULL);
712 * write_undock - write method for "undock" file in sysfs
714 static ssize_t write_undock(struct device *dev, struct device_attribute *attr,
715 const char *buf, size_t count)
718 struct dock_station *dock_station = dev->platform_data;
723 acpi_scan_lock_acquire();
724 begin_undock(dock_station);
725 ret = handle_eject_request(dock_station, ACPI_NOTIFY_EJECT_REQUEST);
726 acpi_scan_lock_release();
727 return ret ? ret: count;
729 static DEVICE_ATTR(undock, S_IWUSR, NULL, write_undock);
732 * show_dock_uid - read method for "uid" file in sysfs
734 static ssize_t show_dock_uid(struct device *dev,
735 struct device_attribute *attr, char *buf)
737 unsigned long long lbuf;
738 struct dock_station *dock_station = dev->platform_data;
739 acpi_status status = acpi_evaluate_integer(dock_station->handle,
740 "_UID", NULL, &lbuf);
741 if (ACPI_FAILURE(status))
744 return snprintf(buf, PAGE_SIZE, "%llx\n", lbuf);
746 static DEVICE_ATTR(uid, S_IRUGO, show_dock_uid, NULL);
748 static ssize_t show_dock_type(struct device *dev,
749 struct device_attribute *attr, char *buf)
751 struct dock_station *dock_station = dev->platform_data;
754 if (dock_station->flags & DOCK_IS_DOCK)
755 type = "dock_station";
756 else if (dock_station->flags & DOCK_IS_ATA)
758 else if (dock_station->flags & DOCK_IS_BAT)
759 type = "battery_bay";
763 return snprintf(buf, PAGE_SIZE, "%s\n", type);
765 static DEVICE_ATTR(type, S_IRUGO, show_dock_type, NULL);
767 static struct attribute *dock_attributes[] = {
768 &dev_attr_docked.attr,
769 &dev_attr_flags.attr,
770 &dev_attr_undock.attr,
776 static struct attribute_group dock_attribute_group = {
777 .attrs = dock_attributes
781 * acpi_dock_add - Add a new dock station
782 * @adev: Dock station ACPI device object.
784 * allocated and initialize a new dock station device.
786 void acpi_dock_add(struct acpi_device *adev)
788 struct dock_station *dock_station, ds = { NULL, };
789 struct platform_device_info pdevinfo;
790 acpi_handle handle = adev->handle;
791 struct platform_device *dd;
794 memset(&pdevinfo, 0, sizeof(pdevinfo));
795 pdevinfo.name = "dock";
796 pdevinfo.id = dock_station_count;
797 pdevinfo.acpi_node.companion = adev;
799 pdevinfo.size_data = sizeof(ds);
800 dd = platform_device_register_full(&pdevinfo);
804 dock_station = dd->dev.platform_data;
806 dock_station->handle = handle;
807 dock_station->dock_device = dd;
808 dock_station->last_dock_time = jiffies - HZ;
810 INIT_LIST_HEAD(&dock_station->sibling);
811 INIT_LIST_HEAD(&dock_station->dependent_devices);
813 /* we want the dock device to send uevents */
814 dev_set_uevent_suppress(&dd->dev, 0);
816 if (acpi_dock_match(handle))
817 dock_station->flags |= DOCK_IS_DOCK;
818 if (acpi_ata_match(handle))
819 dock_station->flags |= DOCK_IS_ATA;
820 if (acpi_device_is_battery(adev))
821 dock_station->flags |= DOCK_IS_BAT;
823 ret = sysfs_create_group(&dd->dev.kobj, &dock_attribute_group);
827 /* add the dock station as a device dependent on itself */
828 ret = add_dock_dependent_device(dock_station, adev);
832 dock_station_count++;
833 list_add(&dock_station->sibling, &dock_stations);
834 adev->flags.is_dock_station = true;
835 dev_info(&adev->dev, "ACPI dock station (docks/bays count: %d)\n",
840 remove_dock_dependent_devices(dock_station);
841 sysfs_remove_group(&dd->dev.kobj, &dock_attribute_group);
843 platform_device_unregister(dd);
844 acpi_handle_err(handle, "%s encountered error %d\n", __func__, ret);