diff options
Diffstat (limited to 'kernel/drivers/acpi/dock.c')
| -rw-r--r-- | kernel/drivers/acpi/dock.c | 666 |
1 files changed, 666 insertions, 0 deletions
diff --git a/kernel/drivers/acpi/dock.c b/kernel/drivers/acpi/dock.c new file mode 100644 index 000000000..a688aa243 --- /dev/null +++ b/kernel/drivers/acpi/dock.c @@ -0,0 +1,666 @@ +/* + * 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> + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or (at + * your option) any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. + * + * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + */ + +#include <linux/kernel.h> +#include <linux/module.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" + +#define ACPI_DOCK_DRIVER_DESCRIPTION "ACPI Dock Station Driver" + +ACPI_MODULE_NAME("dock"); +MODULE_AUTHOR("Kristen Carlson Accardi"); +MODULE_DESCRIPTION(ACPI_DOCK_DRIVER_DESCRIPTION); +MODULE_LICENSE("GPL"); + +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, false); + + 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 */ + 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 show_docked(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dock_station *dock_station = dev->platform_data; + struct acpi_device *adev = NULL; + + acpi_bus_get_device(dock_station->handle, &adev); + return snprintf(buf, PAGE_SIZE, "%u\n", acpi_device_enumerated(adev)); +} +static DEVICE_ATTR(docked, S_IRUGO, show_docked, NULL); + +/* + * show_flags - read method for flags file in sysfs + */ +static ssize_t show_flags(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct dock_station *dock_station = dev->platform_data; + return snprintf(buf, PAGE_SIZE, "%d\n", dock_station->flags); + +} +static DEVICE_ATTR(flags, S_IRUGO, show_flags, NULL); + +/* + * write_undock - write method for "undock" file in sysfs + */ +static ssize_t write_undock(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(undock, S_IWUSR, NULL, write_undock); + +/* + * show_dock_uid - read method for "uid" file in sysfs + */ +static ssize_t show_dock_uid(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 snprintf(buf, PAGE_SIZE, "%llx\n", lbuf); +} +static DEVICE_ATTR(uid, S_IRUGO, show_dock_uid, NULL); + +static ssize_t show_dock_type(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 snprintf(buf, PAGE_SIZE, "%s\n", type); +} +static DEVICE_ATTR(type, S_IRUGO, show_dock_type, NULL); + +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 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); +} |