1 files changed, 646 insertions, 0 deletions

diff --git a/drivers/acpi/dock.c b/drivers/acpi/dock.c
new file mode 100644
index 0000000000..a89bdbe001
--- /dev/null
+++ b/drivers/acpi/dock.c
@@ -0,0 +1,646 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ *  dock.c - ACPI dock station driver
+ *
+ *  Copyright (C) 2006, 2014, Intel Corp.
+ *  Author: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
+ *          Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/moduleparam.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/notifier.h>
+#include <linux/platform_device.h>
+#include <linux/jiffies.h>
+#include <linux/stddef.h>
+#include <linux/acpi.h>
+
+#include "internal.h"
+
+static bool immediate_undock = 1;
+module_param(immediate_undock, bool, 0644);
+MODULE_PARM_DESC(immediate_undock, "1 (default) will cause the driver to "
+	"undock immediately when the undock button is pressed, 0 will cause"
+	" the driver to wait for userspace to write the undock sysfs file "
+	" before undocking");
+
+struct dock_station {
+	acpi_handle handle;
+	unsigned long last_dock_time;
+	u32 flags;
+	struct list_head dependent_devices;
+
+	struct list_head sibling;
+	struct platform_device *dock_device;
+};
+static LIST_HEAD(dock_stations);
+static int dock_station_count;
+
+struct dock_dependent_device {
+	struct list_head list;
+	struct acpi_device *adev;
+};
+
+#define DOCK_DOCKING	0x00000001
+#define DOCK_UNDOCKING  0x00000002
+#define DOCK_IS_DOCK	0x00000010
+#define DOCK_IS_ATA	0x00000020
+#define DOCK_IS_BAT	0x00000040
+#define DOCK_EVENT	3
+#define UNDOCK_EVENT	2
+
+enum dock_callback_type {
+	DOCK_CALL_HANDLER,
+	DOCK_CALL_FIXUP,
+	DOCK_CALL_UEVENT,
+};
+
+/*****************************************************************************
+ *                         Dock Dependent device functions                   *
+ *****************************************************************************/
+/**
+ * add_dock_dependent_device - associate a device with the dock station
+ * @ds: Dock station.
+ * @adev: Dependent ACPI device object.
+ *
+ * Add the dependent device to the dock's dependent device list.
+ */
+static int add_dock_dependent_device(struct dock_station *ds,
+				     struct acpi_device *adev)
+{
+	struct dock_dependent_device *dd;
+
+	dd = kzalloc(sizeof(*dd), GFP_KERNEL);
+	if (!dd)
+		return -ENOMEM;
+
+	dd->adev = adev;
+	INIT_LIST_HEAD(&dd->list);
+	list_add_tail(&dd->list, &ds->dependent_devices);
+
+	return 0;
+}
+
+static void dock_hotplug_event(struct dock_dependent_device *dd, u32 event,
+			       enum dock_callback_type cb_type)
+{
+	struct acpi_device *adev = dd->adev;
+
+	acpi_lock_hp_context();
+
+	if (!adev->hp)
+		goto out;
+
+	if (cb_type == DOCK_CALL_FIXUP) {
+		void (*fixup)(struct acpi_device *);
+
+		fixup = adev->hp->fixup;
+		if (fixup) {
+			acpi_unlock_hp_context();
+			fixup(adev);
+			return;
+		}
+	} else if (cb_type == DOCK_CALL_UEVENT) {
+		void (*uevent)(struct acpi_device *, u32);
+
+		uevent = adev->hp->uevent;
+		if (uevent) {
+			acpi_unlock_hp_context();
+			uevent(adev, event);
+			return;
+		}
+	} else {
+		int (*notify)(struct acpi_device *, u32);
+
+		notify = adev->hp->notify;
+		if (notify) {
+			acpi_unlock_hp_context();
+			notify(adev, event);
+			return;
+		}
+	}
+
+ out:
+	acpi_unlock_hp_context();
+}
+
+static struct dock_station *find_dock_station(acpi_handle handle)
+{
+	struct dock_station *ds;
+
+	list_for_each_entry(ds, &dock_stations, sibling)
+		if (ds->handle == handle)
+			return ds;
+
+	return NULL;
+}
+
+/**
+ * find_dock_dependent_device - get a device dependent on this dock
+ * @ds: the dock station
+ * @adev: ACPI device object to find.
+ *
+ * iterate over the dependent device list for this dock.  If the
+ * dependent device matches the handle, return.
+ */
+static struct dock_dependent_device *
+find_dock_dependent_device(struct dock_station *ds, struct acpi_device *adev)
+{
+	struct dock_dependent_device *dd;
+
+	list_for_each_entry(dd, &ds->dependent_devices, list)
+		if (adev == dd->adev)
+			return dd;
+
+	return NULL;
+}
+
+void register_dock_dependent_device(struct acpi_device *adev,
+				    acpi_handle dshandle)
+{
+	struct dock_station *ds = find_dock_station(dshandle);
+
+	if (ds && !find_dock_dependent_device(ds, adev))
+		add_dock_dependent_device(ds, adev);
+}
+
+/*****************************************************************************
+ *                         Dock functions                                    *
+ *****************************************************************************/
+
+/**
+ * is_dock_device - see if a device is on a dock station
+ * @adev: ACPI device object to check.
+ *
+ * If this device is either the dock station itself,
+ * or is a device dependent on the dock station, then it
+ * is a dock device
+ */
+int is_dock_device(struct acpi_device *adev)
+{
+	struct dock_station *dock_station;
+
+	if (!dock_station_count)
+		return 0;
+
+	if (acpi_dock_match(adev->handle))
+		return 1;
+
+	list_for_each_entry(dock_station, &dock_stations, sibling)
+		if (find_dock_dependent_device(dock_station, adev))
+			return 1;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(is_dock_device);
+
+/**
+ * dock_present - see if the dock station is present.
+ * @ds: the dock station
+ *
+ * execute the _STA method.  note that present does not
+ * imply that we are docked.
+ */
+static int dock_present(struct dock_station *ds)
+{
+	unsigned long long sta;
+	acpi_status status;
+
+	if (ds) {
+		status = acpi_evaluate_integer(ds->handle, "_STA", NULL, &sta);
+		if (ACPI_SUCCESS(status) && sta)
+			return 1;
+	}
+	return 0;
+}
+
+/**
+ * hot_remove_dock_devices - Remove dock station devices.
+ * @ds: Dock station.
+ */
+static void hot_remove_dock_devices(struct dock_station *ds)
+{
+	struct dock_dependent_device *dd;
+
+	/*
+	 * Walk the list in reverse order so that devices that have been added
+	 * last are removed first (in case there are some indirect dependencies
+	 * between them).
+	 */
+	list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
+		dock_hotplug_event(dd, ACPI_NOTIFY_EJECT_REQUEST,
+				   DOCK_CALL_HANDLER);
+
+	list_for_each_entry_reverse(dd, &ds->dependent_devices, list)
+		acpi_bus_trim(dd->adev);
+}
+
+/**
+ * hotplug_dock_devices - Insert devices on a dock station.
+ * @ds: the dock station
+ * @event: either bus check or device check request
+ *
+ * Some devices on the dock station need to have drivers called
+ * to perform hotplug operations after a dock event has occurred.
+ * Traverse the list of dock devices that have registered a
+ * hotplug handler, and call the handler.
+ */
+static void hotplug_dock_devices(struct dock_station *ds, u32 event)
+{
+	struct dock_dependent_device *dd;
+
+	/* Call driver specific post-dock fixups. */
+	list_for_each_entry(dd, &ds->dependent_devices, list)
+		dock_hotplug_event(dd, event, DOCK_CALL_FIXUP);
+
+	/* Call driver specific hotplug functions. */
+	list_for_each_entry(dd, &ds->dependent_devices, list)
+		dock_hotplug_event(dd, event, DOCK_CALL_HANDLER);
+
+	/*
+	 * Check if all devices have been enumerated already.  If not, run
+	 * acpi_bus_scan() for them and that will cause scan handlers to be
+	 * attached to device objects or acpi_drivers to be stopped/started if
+	 * they are present.
+	 */
+	list_for_each_entry(dd, &ds->dependent_devices, list) {
+		struct acpi_device *adev = dd->adev;
+
+		if (!acpi_device_enumerated(adev)) {
+			int ret = acpi_bus_scan(adev->handle);
+
+			if (ret)
+				dev_dbg(&adev->dev, "scan error %d\n", -ret);
+		}
+	}
+}
+
+static void dock_event(struct dock_station *ds, u32 event, int num)
+{
+	struct device *dev = &ds->dock_device->dev;
+	char event_string[13];
+	char *envp[] = { event_string, NULL };
+	struct dock_dependent_device *dd;
+
+	if (num == UNDOCK_EVENT)
+		sprintf(event_string, "EVENT=undock");
+	else
+		sprintf(event_string, "EVENT=dock");
+
+	/*
+	 * Indicate that the status of the dock station has
+	 * changed.
+	 */
+	if (num == DOCK_EVENT)
+		kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
+
+	list_for_each_entry(dd, &ds->dependent_devices, list)
+		dock_hotplug_event(dd, event, DOCK_CALL_UEVENT);
+
+	if (num != DOCK_EVENT)
+		kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
+}
+
+/**
+ * handle_dock - handle a dock event
+ * @ds: the dock station
+ * @dock: to dock, or undock - that is the question
+ *
+ * Execute the _DCK method in response to an acpi event
+ */
+static void handle_dock(struct dock_station *ds, int dock)
+{
+	acpi_status status;
+	struct acpi_object_list arg_list;
+	union acpi_object arg;
+	unsigned long long value;
+
+	acpi_handle_info(ds->handle, "%s\n", dock ? "docking" : "undocking");
+
+	/* _DCK method has one argument */
+	arg_list.count = 1;
+	arg_list.pointer = &arg;
+	arg.type = ACPI_TYPE_INTEGER;
+	arg.integer.value = dock;
+	status = acpi_evaluate_integer(ds->handle, "_DCK", &arg_list, &value);
+	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
+		acpi_handle_err(ds->handle, "Failed to execute _DCK (0x%x)\n",
+				status);
+}
+
+static inline void dock(struct dock_station *ds)
+{
+	handle_dock(ds, 1);
+}
+
+static inline void undock(struct dock_station *ds)
+{
+	handle_dock(ds, 0);
+}
+
+static inline void begin_dock(struct dock_station *ds)
+{
+	ds->flags |= DOCK_DOCKING;
+}
+
+static inline void complete_dock(struct dock_station *ds)
+{
+	ds->flags &= ~(DOCK_DOCKING);
+	ds->last_dock_time = jiffies;
+}
+
+static inline void begin_undock(struct dock_station *ds)
+{
+	ds->flags |= DOCK_UNDOCKING;
+}
+
+static inline void complete_undock(struct dock_station *ds)
+{
+	ds->flags &= ~(DOCK_UNDOCKING);
+}
+
+/**
+ * dock_in_progress - see if we are in the middle of handling a dock event
+ * @ds: the dock station
+ *
+ * Sometimes while docking, false dock events can be sent to the driver
+ * because good connections aren't made or some other reason.  Ignore these
+ * if we are in the middle of doing something.
+ */
+static int dock_in_progress(struct dock_station *ds)
+{
+	if ((ds->flags & DOCK_DOCKING) ||
+	    time_before(jiffies, (ds->last_dock_time + HZ)))
+		return 1;
+	return 0;
+}
+
+/**
+ * handle_eject_request - handle an undock request checking for error conditions
+ *
+ * Check to make sure the dock device is still present, then undock and
+ * hotremove all the devices that may need removing.
+ */
+static int handle_eject_request(struct dock_station *ds, u32 event)
+{
+	if (dock_in_progress(ds))
+		return -EBUSY;
+
+	/*
+	 * here we need to generate the undock
+	 * event prior to actually doing the undock
+	 * so that the device struct still exists.
+	 * Also, even send the dock event if the
+	 * device is not present anymore
+	 */
+	dock_event(ds, event, UNDOCK_EVENT);
+
+	hot_remove_dock_devices(ds);
+	undock(ds);
+	acpi_evaluate_lck(ds->handle, 0);
+	acpi_evaluate_ej0(ds->handle);
+	if (dock_present(ds)) {
+		acpi_handle_err(ds->handle, "Unable to undock!\n");
+		return -EBUSY;
+	}
+	complete_undock(ds);
+	return 0;
+}
+
+/**
+ * dock_notify - Handle ACPI dock notification.
+ * @adev: Dock station's ACPI device object.
+ * @event: Event code.
+ *
+ * If we are notified to dock, then check to see if the dock is
+ * present and then dock.  Notify all drivers of the dock event,
+ * and then hotplug and devices that may need hotplugging.
+ */
+int dock_notify(struct acpi_device *adev, u32 event)
+{
+	acpi_handle handle = adev->handle;
+	struct dock_station *ds = find_dock_station(handle);
+	int surprise_removal = 0;
+
+	if (!ds)
+		return -ENODEV;
+
+	/*
+	 * According to acpi spec 3.0a, if a DEVICE_CHECK notification
+	 * is sent and _DCK is present, it is assumed to mean an undock
+	 * request.
+	 */
+	if ((ds->flags & DOCK_IS_DOCK) && event == ACPI_NOTIFY_DEVICE_CHECK)
+		event = ACPI_NOTIFY_EJECT_REQUEST;
+
+	/*
+	 * dock station: BUS_CHECK - docked or surprise removal
+	 *		 DEVICE_CHECK - undocked
+	 * other device: BUS_CHECK/DEVICE_CHECK - added or surprise removal
+	 *
+	 * To simplify event handling, dock dependent device handler always
+	 * get ACPI_NOTIFY_BUS_CHECK/ACPI_NOTIFY_DEVICE_CHECK for add and
+	 * ACPI_NOTIFY_EJECT_REQUEST for removal
+	 */
+	switch (event) {
+	case ACPI_NOTIFY_BUS_CHECK:
+	case ACPI_NOTIFY_DEVICE_CHECK:
+		if (!dock_in_progress(ds) && !acpi_device_enumerated(adev)) {
+			begin_dock(ds);
+			dock(ds);
+			if (!dock_present(ds)) {
+				acpi_handle_err(handle, "Unable to dock!\n");
+				complete_dock(ds);
+				break;
+			}
+			hotplug_dock_devices(ds, event);
+			complete_dock(ds);
+			dock_event(ds, event, DOCK_EVENT);
+			acpi_evaluate_lck(ds->handle, 1);
+			acpi_update_all_gpes();
+			break;
+		}
+		if (dock_present(ds) || dock_in_progress(ds))
+			break;
+		/* This is a surprise removal */
+		surprise_removal = 1;
+		event = ACPI_NOTIFY_EJECT_REQUEST;
+		/* Fall back */
+		fallthrough;
+	case ACPI_NOTIFY_EJECT_REQUEST:
+		begin_undock(ds);
+		if ((immediate_undock && !(ds->flags & DOCK_IS_ATA))
+		   || surprise_removal)
+			handle_eject_request(ds, event);
+		else
+			dock_event(ds, event, UNDOCK_EVENT);
+		break;
+	}
+	return 0;
+}
+
+/*
+ * show_docked - read method for "docked" file in sysfs
+ */
+static ssize_t docked_show(struct device *dev,
+			   struct device_attribute *attr, char *buf)
+{
+	struct dock_station *dock_station = dev->platform_data;
+	struct acpi_device *adev = acpi_fetch_acpi_dev(dock_station->handle);
+
+	return sysfs_emit(buf, "%u\n", acpi_device_enumerated(adev));
+}
+static DEVICE_ATTR_RO(docked);
+
+/*
+ * show_flags - read method for flags file in sysfs
+ */
+static ssize_t flags_show(struct device *dev,
+			  struct device_attribute *attr, char *buf)
+{
+	struct dock_station *dock_station = dev->platform_data;
+
+	return sysfs_emit(buf, "%d\n", dock_station->flags);
+
+}
+static DEVICE_ATTR_RO(flags);
+
+/*
+ * write_undock - write method for "undock" file in sysfs
+ */
+static ssize_t undock_store(struct device *dev, struct device_attribute *attr,
+			    const char *buf, size_t count)
+{
+	int ret;
+	struct dock_station *dock_station = dev->platform_data;
+
+	if (!count)
+		return -EINVAL;
+
+	acpi_scan_lock_acquire();
+	begin_undock(dock_station);
+	ret = handle_eject_request(dock_station, ACPI_NOTIFY_EJECT_REQUEST);
+	acpi_scan_lock_release();
+	return ret ? ret : count;
+}
+static DEVICE_ATTR_WO(undock);
+
+/*
+ * show_dock_uid - read method for "uid" file in sysfs
+ */
+static ssize_t uid_show(struct device *dev,
+			struct device_attribute *attr, char *buf)
+{
+	unsigned long long lbuf;
+	struct dock_station *dock_station = dev->platform_data;
+
+	acpi_status status = acpi_evaluate_integer(dock_station->handle,
+					"_UID", NULL, &lbuf);
+	if (ACPI_FAILURE(status))
+		return 0;
+
+	return sysfs_emit(buf, "%llx\n", lbuf);
+}
+static DEVICE_ATTR_RO(uid);
+
+static ssize_t type_show(struct device *dev,
+			 struct device_attribute *attr, char *buf)
+{
+	struct dock_station *dock_station = dev->platform_data;
+	char *type;
+
+	if (dock_station->flags & DOCK_IS_DOCK)
+		type = "dock_station";
+	else if (dock_station->flags & DOCK_IS_ATA)
+		type = "ata_bay";
+	else if (dock_station->flags & DOCK_IS_BAT)
+		type = "battery_bay";
+	else
+		type = "unknown";
+
+	return sysfs_emit(buf, "%s\n", type);
+}
+static DEVICE_ATTR_RO(type);
+
+static struct attribute *dock_attributes[] = {
+	&dev_attr_docked.attr,
+	&dev_attr_flags.attr,
+	&dev_attr_undock.attr,
+	&dev_attr_uid.attr,
+	&dev_attr_type.attr,
+	NULL
+};
+
+static const struct attribute_group dock_attribute_group = {
+	.attrs = dock_attributes
+};
+
+/**
+ * acpi_dock_add - Add a new dock station
+ * @adev: Dock station ACPI device object.
+ *
+ * allocated and initialize a new dock station device.
+ */
+void acpi_dock_add(struct acpi_device *adev)
+{
+	struct dock_station *dock_station, ds = { NULL, };
+	struct platform_device_info pdevinfo;
+	acpi_handle handle = adev->handle;
+	struct platform_device *dd;
+	int ret;
+
+	memset(&pdevinfo, 0, sizeof(pdevinfo));
+	pdevinfo.name = "dock";
+	pdevinfo.id = dock_station_count;
+	pdevinfo.fwnode = acpi_fwnode_handle(adev);
+	pdevinfo.data = &ds;
+	pdevinfo.size_data = sizeof(ds);
+	dd = platform_device_register_full(&pdevinfo);
+	if (IS_ERR(dd))
+		return;
+
+	dock_station = dd->dev.platform_data;
+
+	dock_station->handle = handle;
+	dock_station->dock_device = dd;
+	dock_station->last_dock_time = jiffies - HZ;
+
+	INIT_LIST_HEAD(&dock_station->sibling);
+	INIT_LIST_HEAD(&dock_station->dependent_devices);
+
+	/* we want the dock device to send uevents */
+	dev_set_uevent_suppress(&dd->dev, 0);
+
+	if (acpi_dock_match(handle))
+		dock_station->flags |= DOCK_IS_DOCK;
+	if (acpi_ata_match(handle))
+		dock_station->flags |= DOCK_IS_ATA;
+	if (acpi_device_is_battery(adev))
+		dock_station->flags |= DOCK_IS_BAT;
+
+	ret = sysfs_create_group(&dd->dev.kobj, &dock_attribute_group);
+	if (ret)
+		goto err_unregister;
+
+	/* add the dock station as a device dependent on itself */
+	ret = add_dock_dependent_device(dock_station, adev);
+	if (ret)
+		goto err_rmgroup;
+
+	dock_station_count++;
+	list_add(&dock_station->sibling, &dock_stations);
+	adev->flags.is_dock_station = true;
+	dev_info(&adev->dev, "ACPI dock station (docks/bays count: %d)\n",
+		 dock_station_count);
+	return;
+
+err_rmgroup:
+	sysfs_remove_group(&dd->dev.kobj, &dock_attribute_group);
+
+err_unregister:
+	platform_device_unregister(dd);
+	acpi_handle_err(handle, "%s encountered error %d\n", __func__, ret);
+}