/*
* 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.acpi_node.companion = 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);
}
