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v5.9
  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}
v3.15
 
  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 *  You should have received a copy of the GNU General Public License along
 21 *  with this program; if not, write to the Free Software Foundation, Inc.,
 22 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 23 *
 24 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 25 */
 26
 27#include <linux/kernel.h>
 28#include <linux/module.h>
 29#include <linux/slab.h>
 30#include <linux/init.h>
 31#include <linux/types.h>
 32#include <linux/notifier.h>
 33#include <linux/platform_device.h>
 34#include <linux/jiffies.h>
 35#include <linux/stddef.h>
 36#include <linux/acpi.h>
 37
 38#include "internal.h"
 39
 40#define ACPI_DOCK_DRIVER_DESCRIPTION "ACPI Dock Station Driver"
 41
 42ACPI_MODULE_NAME("dock");
 43MODULE_AUTHOR("Kristen Carlson Accardi");
 44MODULE_DESCRIPTION(ACPI_DOCK_DRIVER_DESCRIPTION);
 45MODULE_LICENSE("GPL");
 46
 47static bool immediate_undock = 1;
 48module_param(immediate_undock, bool, 0644);
 49MODULE_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 "
 52	" before undocking");
 53
 54struct dock_station {
 55	acpi_handle handle;
 56	unsigned long last_dock_time;
 57	u32 flags;
 58	struct list_head dependent_devices;
 59
 60	struct list_head sibling;
 61	struct platform_device *dock_device;
 62};
 63static LIST_HEAD(dock_stations);
 64static int dock_station_count;
 65
 66struct dock_dependent_device {
 67	struct list_head list;
 68	struct acpi_device *adev;
 69};
 70
 71#define DOCK_DOCKING	0x00000001
 72#define DOCK_UNDOCKING  0x00000002
 73#define DOCK_IS_DOCK	0x00000010
 74#define DOCK_IS_ATA	0x00000020
 75#define DOCK_IS_BAT	0x00000040
 76#define DOCK_EVENT	3
 77#define UNDOCK_EVENT	2
 78
 79enum dock_callback_type {
 80	DOCK_CALL_HANDLER,
 81	DOCK_CALL_FIXUP,
 82	DOCK_CALL_UEVENT,
 83};
 84
 85/*****************************************************************************
 86 *                         Dock Dependent device functions                   *
 87 *****************************************************************************/
 88/**
 89 * add_dock_dependent_device - associate a device with the dock station
 90 * @ds: Dock station.
 91 * @adev: Dependent ACPI device object.
 92 *
 93 * Add the dependent device to the dock's dependent device list.
 94 */
 95static int add_dock_dependent_device(struct dock_station *ds,
 96				     struct acpi_device *adev)
 97{
 98	struct dock_dependent_device *dd;
 99
100	dd = kzalloc(sizeof(*dd), GFP_KERNEL);
101	if (!dd)
102		return -ENOMEM;
103
104	dd->adev = adev;
105	INIT_LIST_HEAD(&dd->list);
106	list_add_tail(&dd->list, &ds->dependent_devices);
107
108	return 0;
109}
110
111static void dock_hotplug_event(struct dock_dependent_device *dd, u32 event,
112			       enum dock_callback_type cb_type)
113{
114	struct acpi_device *adev = dd->adev;
115
116	acpi_lock_hp_context();
117
118	if (!adev->hp)
119		goto out;
120
121	if (cb_type == DOCK_CALL_FIXUP) {
122		void (*fixup)(struct acpi_device *);
123
124		fixup = adev->hp->fixup;
125		if (fixup) {
126			acpi_unlock_hp_context();
127			fixup(adev);
128			return;
129		}
130	} else if (cb_type == DOCK_CALL_UEVENT) {
131		void (*uevent)(struct acpi_device *, u32);
132
133		uevent = adev->hp->uevent;
134		if (uevent) {
135			acpi_unlock_hp_context();
136			uevent(adev, event);
137			return;
138		}
139	} else {
140		int (*notify)(struct acpi_device *, u32);
141
142		notify = adev->hp->notify;
143		if (notify) {
144			acpi_unlock_hp_context();
145			notify(adev, event);
146			return;
147		}
148	}
149
150 out:
151	acpi_unlock_hp_context();
152}
153
154static struct dock_station *find_dock_station(acpi_handle handle)
155{
156	struct dock_station *ds;
157
158	list_for_each_entry(ds, &dock_stations, sibling)
159		if (ds->handle == handle)
160			return ds;
161
162	return NULL;
163}
164
165/**
166 * find_dock_dependent_device - get a device dependent on this dock
167 * @ds: the dock station
168 * @adev: ACPI device object to find.
169 *
170 * iterate over the dependent device list for this dock.  If the
171 * dependent device matches the handle, return.
172 */
173static struct dock_dependent_device *
174find_dock_dependent_device(struct dock_station *ds, struct acpi_device *adev)
175{
176	struct dock_dependent_device *dd;
177
178	list_for_each_entry(dd, &ds->dependent_devices, list)
179		if (adev == dd->adev)
180			return dd;
181
182	return NULL;
183}
184
185void register_dock_dependent_device(struct acpi_device *adev,
186				    acpi_handle dshandle)
187{
188	struct dock_station *ds = find_dock_station(dshandle);
189
190	if (ds && !find_dock_dependent_device(ds, adev))
191		add_dock_dependent_device(ds, adev);
192}
193
194/*****************************************************************************
195 *                         Dock functions                                    *
196 *****************************************************************************/
197
198/**
199 * is_dock_device - see if a device is on a dock station
200 * @adev: ACPI device object to check.
201 *
202 * If this device is either the dock station itself,
203 * or is a device dependent on the dock station, then it
204 * is a dock device
205 */
206int is_dock_device(struct acpi_device *adev)
207{
208	struct dock_station *dock_station;
209
210	if (!dock_station_count)
211		return 0;
212
213	if (acpi_dock_match(adev->handle))
214		return 1;
215
216	list_for_each_entry(dock_station, &dock_stations, sibling)
217		if (find_dock_dependent_device(dock_station, adev))
218			return 1;
219
220	return 0;
221}
222EXPORT_SYMBOL_GPL(is_dock_device);
223
224/**
225 * dock_present - see if the dock station is present.
226 * @ds: the dock station
227 *
228 * execute the _STA method.  note that present does not
229 * imply that we are docked.
230 */
231static int dock_present(struct dock_station *ds)
232{
233	unsigned long long sta;
234	acpi_status status;
235
236	if (ds) {
237		status = acpi_evaluate_integer(ds->handle, "_STA", NULL, &sta);
238		if (ACPI_SUCCESS(status) && sta)
239			return 1;
240	}
241	return 0;
242}
243
244/**
245 * hot_remove_dock_devices - Remove dock station devices.
246 * @ds: Dock station.
247 */
248static void hot_remove_dock_devices(struct dock_station *ds)
249{
250	struct dock_dependent_device *dd;
251
252	/*
253	 * Walk the list in reverse order so that devices that have been added
254	 * last are removed first (in case there are some indirect dependencies
255	 * between them).
256	 */
257	list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
258		dock_hotplug_event(dd, ACPI_NOTIFY_EJECT_REQUEST, false);
259
260	list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
261		acpi_bus_trim(dd->adev);
262}
263
264/**
265 * hotplug_dock_devices - Insert devices on a dock station.
266 * @ds: the dock station
267 * @event: either bus check or device check request
268 *
269 * Some devices on the dock station need to have drivers called
270 * to perform hotplug operations after a dock event has occurred.
271 * Traverse the list of dock devices that have registered a
272 * hotplug handler, and call the handler.
273 */
274static void hotplug_dock_devices(struct dock_station *ds, u32 event)
275{
276	struct dock_dependent_device *dd;
277
278	/* Call driver specific post-dock fixups. */
279	list_for_each_entry(dd, &ds->dependent_devices, list)
280		dock_hotplug_event(dd, event, DOCK_CALL_FIXUP);
281
282	/* Call driver specific hotplug functions. */
283	list_for_each_entry(dd, &ds->dependent_devices, list)
284		dock_hotplug_event(dd, event, DOCK_CALL_HANDLER);
285
286	/*
287	 * Check if all devices have been enumerated already.  If not, run
288	 * acpi_bus_scan() for them and that will cause scan handlers to be
289	 * attached to device objects or acpi_drivers to be stopped/started if
290	 * they are present.
291	 */
292	list_for_each_entry(dd, &ds->dependent_devices, list) {
293		struct acpi_device *adev = dd->adev;
294
295		if (!acpi_device_enumerated(adev)) {
296			int ret = acpi_bus_scan(adev->handle);
297			if (ret)
298				dev_dbg(&adev->dev, "scan error %d\n", -ret);
299		}
300	}
301}
302
303static void dock_event(struct dock_station *ds, u32 event, int num)
304{
305	struct device *dev = &ds->dock_device->dev;
306	char event_string[13];
307	char *envp[] = { event_string, NULL };
308	struct dock_dependent_device *dd;
309
310	if (num == UNDOCK_EVENT)
311		sprintf(event_string, "EVENT=undock");
312	else
313		sprintf(event_string, "EVENT=dock");
314
315	/*
316	 * Indicate that the status of the dock station has
317	 * changed.
318	 */
319	if (num == DOCK_EVENT)
320		kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
321
322	list_for_each_entry(dd, &ds->dependent_devices, list)
323		dock_hotplug_event(dd, event, DOCK_CALL_UEVENT);
324
325	if (num != DOCK_EVENT)
326		kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
327}
328
329/**
330 * handle_dock - handle a dock event
331 * @ds: the dock station
332 * @dock: to dock, or undock - that is the question
333 *
334 * Execute the _DCK method in response to an acpi event
335 */
336static void handle_dock(struct dock_station *ds, int dock)
337{
338	acpi_status status;
339	struct acpi_object_list arg_list;
340	union acpi_object arg;
341	unsigned long long value;
342
343	acpi_handle_info(ds->handle, "%s\n", dock ? "docking" : "undocking");
344
345	/* _DCK method has one argument */
346	arg_list.count = 1;
347	arg_list.pointer = &arg;
348	arg.type = ACPI_TYPE_INTEGER;
349	arg.integer.value = dock;
350	status = acpi_evaluate_integer(ds->handle, "_DCK", &arg_list, &value);
351	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
352		acpi_handle_err(ds->handle, "Failed to execute _DCK (0x%x)\n",
353				status);
354}
355
356static inline void dock(struct dock_station *ds)
357{
358	handle_dock(ds, 1);
359}
360
361static inline void undock(struct dock_station *ds)
362{
363	handle_dock(ds, 0);
364}
365
366static inline void begin_dock(struct dock_station *ds)
367{
368	ds->flags |= DOCK_DOCKING;
369}
370
371static inline void complete_dock(struct dock_station *ds)
372{
373	ds->flags &= ~(DOCK_DOCKING);
374	ds->last_dock_time = jiffies;
375}
376
377static inline void begin_undock(struct dock_station *ds)
378{
379	ds->flags |= DOCK_UNDOCKING;
380}
381
382static inline void complete_undock(struct dock_station *ds)
383{
384	ds->flags &= ~(DOCK_UNDOCKING);
385}
386
387/**
388 * dock_in_progress - see if we are in the middle of handling a dock event
389 * @ds: the dock station
390 *
391 * Sometimes while docking, false dock events can be sent to the driver
392 * because good connections aren't made or some other reason.  Ignore these
393 * if we are in the middle of doing something.
394 */
395static int dock_in_progress(struct dock_station *ds)
396{
397	if ((ds->flags & DOCK_DOCKING) ||
398	    time_before(jiffies, (ds->last_dock_time + HZ)))
399		return 1;
400	return 0;
401}
402
403/**
404 * handle_eject_request - handle an undock request checking for error conditions
405 *
406 * Check to make sure the dock device is still present, then undock and
407 * hotremove all the devices that may need removing.
408 */
409static int handle_eject_request(struct dock_station *ds, u32 event)
410{
411	if (dock_in_progress(ds))
412		return -EBUSY;
413
414	/*
415	 * here we need to generate the undock
416	 * event prior to actually doing the undock
417	 * so that the device struct still exists.
418	 * Also, even send the dock event if the
419	 * device is not present anymore
420	 */
421	dock_event(ds, event, UNDOCK_EVENT);
422
423	hot_remove_dock_devices(ds);
424	undock(ds);
425	acpi_evaluate_lck(ds->handle, 0);
426	acpi_evaluate_ej0(ds->handle);
427	if (dock_present(ds)) {
428		acpi_handle_err(ds->handle, "Unable to undock!\n");
429		return -EBUSY;
430	}
431	complete_undock(ds);
432	return 0;
433}
434
435/**
436 * dock_notify - Handle ACPI dock notification.
437 * @adev: Dock station's ACPI device object.
438 * @event: Event code.
439 *
440 * If we are notified to dock, then check to see if the dock is
441 * present and then dock.  Notify all drivers of the dock event,
442 * and then hotplug and devices that may need hotplugging.
443 */
444int dock_notify(struct acpi_device *adev, u32 event)
445{
446	acpi_handle handle = adev->handle;
447	struct dock_station *ds = find_dock_station(handle);
448	int surprise_removal = 0;
449
450	if (!ds)
451		return -ENODEV;
452
453	/*
454	 * According to acpi spec 3.0a, if a DEVICE_CHECK notification
455	 * is sent and _DCK is present, it is assumed to mean an undock
456	 * request.
457	 */
458	if ((ds->flags & DOCK_IS_DOCK) && event == ACPI_NOTIFY_DEVICE_CHECK)
459		event = ACPI_NOTIFY_EJECT_REQUEST;
460
461	/*
462	 * dock station: BUS_CHECK - docked or surprise removal
463	 *		 DEVICE_CHECK - undocked
464	 * other device: BUS_CHECK/DEVICE_CHECK - added or surprise removal
465	 *
466	 * To simplify event handling, dock dependent device handler always
467	 * get ACPI_NOTIFY_BUS_CHECK/ACPI_NOTIFY_DEVICE_CHECK for add and
468	 * ACPI_NOTIFY_EJECT_REQUEST for removal
469	 */
470	switch (event) {
471	case ACPI_NOTIFY_BUS_CHECK:
472	case ACPI_NOTIFY_DEVICE_CHECK:
473		if (!dock_in_progress(ds) && !acpi_device_enumerated(adev)) {
474			begin_dock(ds);
475			dock(ds);
476			if (!dock_present(ds)) {
477				acpi_handle_err(handle, "Unable to dock!\n");
478				complete_dock(ds);
479				break;
480			}
481			hotplug_dock_devices(ds, event);
482			complete_dock(ds);
483			dock_event(ds, event, DOCK_EVENT);
484			acpi_evaluate_lck(ds->handle, 1);
485			acpi_update_all_gpes();
486			break;
487		}
488		if (dock_present(ds) || dock_in_progress(ds))
489			break;
490		/* This is a surprise removal */
491		surprise_removal = 1;
492		event = ACPI_NOTIFY_EJECT_REQUEST;
493		/* Fall back */
 
494	case ACPI_NOTIFY_EJECT_REQUEST:
495		begin_undock(ds);
496		if ((immediate_undock && !(ds->flags & DOCK_IS_ATA))
497		   || surprise_removal)
498			handle_eject_request(ds, event);
499		else
500			dock_event(ds, event, UNDOCK_EVENT);
501		break;
502	}
503	return 0;
504}
505
506/*
507 * show_docked - read method for "docked" file in sysfs
508 */
509static ssize_t show_docked(struct device *dev,
510			   struct device_attribute *attr, char *buf)
511{
512	struct dock_station *dock_station = dev->platform_data;
513	struct acpi_device *adev = NULL;
514
515	acpi_bus_get_device(dock_station->handle, &adev);
516	return snprintf(buf, PAGE_SIZE, "%u\n", acpi_device_enumerated(adev));
517}
518static DEVICE_ATTR(docked, S_IRUGO, show_docked, NULL);
519
520/*
521 * show_flags - read method for flags file in sysfs
522 */
523static ssize_t show_flags(struct device *dev,
524			  struct device_attribute *attr, char *buf)
525{
526	struct dock_station *dock_station = dev->platform_data;
527	return snprintf(buf, PAGE_SIZE, "%d\n", dock_station->flags);
528
529}
530static DEVICE_ATTR(flags, S_IRUGO, show_flags, NULL);
531
532/*
533 * write_undock - write method for "undock" file in sysfs
534 */
535static ssize_t write_undock(struct device *dev, struct device_attribute *attr,
536			   const char *buf, size_t count)
537{
538	int ret;
539	struct dock_station *dock_station = dev->platform_data;
540
541	if (!count)
542		return -EINVAL;
543
544	acpi_scan_lock_acquire();
545	begin_undock(dock_station);
546	ret = handle_eject_request(dock_station, ACPI_NOTIFY_EJECT_REQUEST);
547	acpi_scan_lock_release();
548	return ret ? ret: count;
549}
550static DEVICE_ATTR(undock, S_IWUSR, NULL, write_undock);
551
552/*
553 * show_dock_uid - read method for "uid" file in sysfs
554 */
555static ssize_t show_dock_uid(struct device *dev,
556			     struct device_attribute *attr, char *buf)
557{
558	unsigned long long lbuf;
559	struct dock_station *dock_station = dev->platform_data;
560	acpi_status status = acpi_evaluate_integer(dock_station->handle,
561					"_UID", NULL, &lbuf);
562	if (ACPI_FAILURE(status))
563	    return 0;
564
565	return snprintf(buf, PAGE_SIZE, "%llx\n", lbuf);
566}
567static DEVICE_ATTR(uid, S_IRUGO, show_dock_uid, NULL);
568
569static ssize_t show_dock_type(struct device *dev,
570		struct device_attribute *attr, char *buf)
571{
572	struct dock_station *dock_station = dev->platform_data;
573	char *type;
574
575	if (dock_station->flags & DOCK_IS_DOCK)
576		type = "dock_station";
577	else if (dock_station->flags & DOCK_IS_ATA)
578		type = "ata_bay";
579	else if (dock_station->flags & DOCK_IS_BAT)
580		type = "battery_bay";
581	else
582		type = "unknown";
583
584	return snprintf(buf, PAGE_SIZE, "%s\n", type);
585}
586static DEVICE_ATTR(type, S_IRUGO, show_dock_type, NULL);
587
588static struct attribute *dock_attributes[] = {
589	&dev_attr_docked.attr,
590	&dev_attr_flags.attr,
591	&dev_attr_undock.attr,
592	&dev_attr_uid.attr,
593	&dev_attr_type.attr,
594	NULL
595};
596
597static struct attribute_group dock_attribute_group = {
598	.attrs = dock_attributes
599};
600
601/**
602 * acpi_dock_add - Add a new dock station
603 * @adev: Dock station ACPI device object.
604 *
605 * allocated and initialize a new dock station device.
606 */
607void acpi_dock_add(struct acpi_device *adev)
608{
609	struct dock_station *dock_station, ds = { NULL, };
610	struct platform_device_info pdevinfo;
611	acpi_handle handle = adev->handle;
612	struct platform_device *dd;
613	int ret;
614
615	memset(&pdevinfo, 0, sizeof(pdevinfo));
616	pdevinfo.name = "dock";
617	pdevinfo.id = dock_station_count;
618	pdevinfo.acpi_node.companion = adev;
619	pdevinfo.data = &ds;
620	pdevinfo.size_data = sizeof(ds);
621	dd = platform_device_register_full(&pdevinfo);
622	if (IS_ERR(dd))
623		return;
624
625	dock_station = dd->dev.platform_data;
626
627	dock_station->handle = handle;
628	dock_station->dock_device = dd;
629	dock_station->last_dock_time = jiffies - HZ;
630
631	INIT_LIST_HEAD(&dock_station->sibling);
632	INIT_LIST_HEAD(&dock_station->dependent_devices);
633
634	/* we want the dock device to send uevents */
635	dev_set_uevent_suppress(&dd->dev, 0);
636
637	if (acpi_dock_match(handle))
638		dock_station->flags |= DOCK_IS_DOCK;
639	if (acpi_ata_match(handle))
640		dock_station->flags |= DOCK_IS_ATA;
641	if (acpi_device_is_battery(adev))
642		dock_station->flags |= DOCK_IS_BAT;
643
644	ret = sysfs_create_group(&dd->dev.kobj, &dock_attribute_group);
645	if (ret)
646		goto err_unregister;
647
648	/* add the dock station as a device dependent on itself */
649	ret = add_dock_dependent_device(dock_station, adev);
650	if (ret)
651		goto err_rmgroup;
652
653	dock_station_count++;
654	list_add(&dock_station->sibling, &dock_stations);
655	adev->flags.is_dock_station = true;
656	dev_info(&adev->dev, "ACPI dock station (docks/bays count: %d)\n",
657		 dock_station_count);
658	return;
659
660err_rmgroup:
661	sysfs_remove_group(&dd->dev.kobj, &dock_attribute_group);
662
663err_unregister:
664	platform_device_unregister(dd);
665	acpi_handle_err(handle, "%s encountered error %d\n", __func__, ret);
666}