linux/drivers/acpi/dock.c
Rafael J. Wysocki bfee26dba0 ACPI / scan: Make it clear that acpi_bus_trim() cannot fail
Since acpi_bus_trim() cannot fail, change its definition to a void
function, so that its callers don't check the return value in vain
and update the callers.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Acked-by: Toshi Kani <toshi.kani@hp.com>
2013-01-26 00:27:44 +01:00

1058 lines
27 KiB
C

/*
* dock.c - ACPI dock station driver
*
* Copyright (C) 2006 Kristen Carlson Accardi <kristen.c.accardi@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 <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#define PREFIX "ACPI: "
#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");
static struct atomic_notifier_head dock_notifier_list;
static const struct acpi_device_id dock_device_ids[] = {
{"LNXDOCK", 0},
{"", 0},
};
MODULE_DEVICE_TABLE(acpi, dock_device_ids);
struct dock_station {
acpi_handle handle;
unsigned long last_dock_time;
u32 flags;
spinlock_t dd_lock;
struct mutex hp_lock;
struct list_head dependent_devices;
struct list_head hotplug_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 list_head hotplug_list;
acpi_handle handle;
const struct acpi_dock_ops *ops;
void *context;
};
#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
/*****************************************************************************
* Dock Dependent device functions *
*****************************************************************************/
/**
* add_dock_dependent_device - associate a device with the dock station
* @ds: The dock station
* @handle: handle of the dependent device
*
* Add the dependent device to the dock's dependent device list.
*/
static int
add_dock_dependent_device(struct dock_station *ds, acpi_handle handle)
{
struct dock_dependent_device *dd;
dd = kzalloc(sizeof(*dd), GFP_KERNEL);
if (!dd)
return -ENOMEM;
dd->handle = handle;
INIT_LIST_HEAD(&dd->list);
INIT_LIST_HEAD(&dd->hotplug_list);
spin_lock(&ds->dd_lock);
list_add_tail(&dd->list, &ds->dependent_devices);
spin_unlock(&ds->dd_lock);
return 0;
}
/**
* dock_add_hotplug_device - associate a hotplug handler with the dock station
* @ds: The dock station
* @dd: The dependent device struct
*
* Add the dependent device to the dock's hotplug device list
*/
static void
dock_add_hotplug_device(struct dock_station *ds,
struct dock_dependent_device *dd)
{
mutex_lock(&ds->hp_lock);
list_add_tail(&dd->hotplug_list, &ds->hotplug_devices);
mutex_unlock(&ds->hp_lock);
}
/**
* dock_del_hotplug_device - remove a hotplug handler from the dock station
* @ds: The dock station
* @dd: the dependent device struct
*
* Delete the dependent device from the dock's hotplug device list
*/
static void
dock_del_hotplug_device(struct dock_station *ds,
struct dock_dependent_device *dd)
{
mutex_lock(&ds->hp_lock);
list_del(&dd->hotplug_list);
mutex_unlock(&ds->hp_lock);
}
/**
* find_dock_dependent_device - get a device dependent on this dock
* @ds: the dock station
* @handle: the acpi_handle of the device we want
*
* 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, acpi_handle handle)
{
struct dock_dependent_device *dd;
spin_lock(&ds->dd_lock);
list_for_each_entry(dd, &ds->dependent_devices, list) {
if (handle == dd->handle) {
spin_unlock(&ds->dd_lock);
return dd;
}
}
spin_unlock(&ds->dd_lock);
return NULL;
}
/*****************************************************************************
* Dock functions *
*****************************************************************************/
/**
* is_dock - see if a device is a dock station
* @handle: acpi handle of the device
*
* If an acpi object has a _DCK method, then it is by definition a dock
* station, so return true.
*/
static int is_dock(acpi_handle handle)
{
acpi_status status;
acpi_handle tmp;
status = acpi_get_handle(handle, "_DCK", &tmp);
if (ACPI_FAILURE(status))
return 0;
return 1;
}
static int is_ejectable(acpi_handle handle)
{
acpi_status status;
acpi_handle tmp;
status = acpi_get_handle(handle, "_EJ0", &tmp);
if (ACPI_FAILURE(status))
return 0;
return 1;
}
static int is_ata(acpi_handle handle)
{
acpi_handle tmp;
if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) ||
(ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) ||
(ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) ||
(ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp))))
return 1;
return 0;
}
static int is_battery(acpi_handle handle)
{
struct acpi_device_info *info;
int ret = 1;
if (!ACPI_SUCCESS(acpi_get_object_info(handle, &info)))
return 0;
if (!(info->valid & ACPI_VALID_HID))
ret = 0;
else
ret = !strcmp("PNP0C0A", info->hardware_id.string);
kfree(info);
return ret;
}
static int is_ejectable_bay(acpi_handle handle)
{
acpi_handle phandle;
if (!is_ejectable(handle))
return 0;
if (is_battery(handle) || is_ata(handle))
return 1;
if (!acpi_get_parent(handle, &phandle) && is_ata(phandle))
return 1;
return 0;
}
/**
* is_dock_device - see if a device is on a dock station
* @handle: acpi handle of the device
*
* 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(acpi_handle handle)
{
struct dock_station *dock_station;
if (!dock_station_count)
return 0;
if (is_dock(handle))
return 1;
list_for_each_entry(dock_station, &dock_stations, sibling)
if (find_dock_dependent_device(dock_station, handle))
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;
}
/**
* dock_create_acpi_device - add new devices to acpi
* @handle - handle of the device to add
*
* This function will create a new acpi_device for the given
* handle if one does not exist already. This should cause
* acpi to scan for drivers for the given devices, and call
* matching driver's add routine.
*
* Returns a pointer to the acpi_device corresponding to the handle.
*/
static struct acpi_device * dock_create_acpi_device(acpi_handle handle)
{
struct acpi_device *device;
int ret;
if (acpi_bus_get_device(handle, &device)) {
/*
* no device created for this object,
* so we should create one.
*/
ret = acpi_bus_scan(handle);
if (ret)
pr_debug("error adding bus, %x\n", -ret);
acpi_bus_get_device(handle, &device);
}
return device;
}
/**
* dock_remove_acpi_device - remove the acpi_device struct from acpi
* @handle - the handle of the device to remove
*
* Tell acpi to remove the acpi_device. This should cause any loaded
* driver to have it's remove routine called.
*/
static void dock_remove_acpi_device(acpi_handle handle)
{
struct acpi_device *device;
if (!acpi_bus_get_device(handle, &device))
acpi_bus_trim(device);
}
/**
* hotplug_dock_devices - insert or remove devices on the dock station
* @ds: the dock station
* @event: either bus check or eject 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;
mutex_lock(&ds->hp_lock);
/*
* First call driver specific hotplug functions
*/
list_for_each_entry(dd, &ds->hotplug_devices, hotplug_list)
if (dd->ops && dd->ops->handler)
dd->ops->handler(dd->handle, event, dd->context);
/*
* Now make sure that an acpi_device is created for each
* dependent device, or removed if this is an eject request.
* This will cause acpi_drivers to be stopped/started if they
* exist
*/
list_for_each_entry(dd, &ds->dependent_devices, list) {
if (event == ACPI_NOTIFY_EJECT_REQUEST)
dock_remove_acpi_device(dd->handle);
else
dock_create_acpi_device(dd->handle);
}
mutex_unlock(&ds->hp_lock);
}
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->hotplug_devices, hotplug_list)
if (dd->ops && dd->ops->uevent)
dd->ops->uevent(dd->handle, event, dd->context);
if (num != DOCK_EVENT)
kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
}
/**
* eject_dock - respond to a dock eject request
* @ds: the dock station
*
* This is called after _DCK is called, to execute the dock station's
* _EJ0 method.
*/
static void eject_dock(struct dock_station *ds)
{
struct acpi_object_list arg_list;
union acpi_object arg;
acpi_status status;
acpi_handle tmp;
/* all dock devices should have _EJ0, but check anyway */
status = acpi_get_handle(ds->handle, "_EJ0", &tmp);
if (ACPI_FAILURE(status)) {
pr_debug("No _EJ0 support for dock device\n");
return;
}
arg_list.count = 1;
arg_list.pointer = &arg;
arg.type = ACPI_TYPE_INTEGER;
arg.integer.value = 1;
status = acpi_evaluate_object(ds->handle, "_EJ0", &arg_list, NULL);
if (ACPI_FAILURE(status))
pr_debug("Failed to evaluate _EJ0!\n");
}
/**
* 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;
struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
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_object(ds->handle, "_DCK", &arg_list, &buffer);
if (ACPI_FAILURE(status) && status != AE_NOT_FOUND)
acpi_handle_err(ds->handle, "Failed to execute _DCK (0x%x)\n",
status);
kfree(buffer.pointer);
}
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);
}
static void dock_lock(struct dock_station *ds, int lock)
{
struct acpi_object_list arg_list;
union acpi_object arg;
acpi_status status;
arg_list.count = 1;
arg_list.pointer = &arg;
arg.type = ACPI_TYPE_INTEGER;
arg.integer.value = !!lock;
status = acpi_evaluate_object(ds->handle, "_LCK", &arg_list, NULL);
if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
if (lock)
acpi_handle_warn(ds->handle,
"Locking device failed (0x%x)\n", status);
else
acpi_handle_warn(ds->handle,
"Unlocking device failed (0x%x)\n", status);
}
}
/**
* 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;
}
/**
* register_dock_notifier - add yourself to the dock notifier list
* @nb: the callers notifier block
*
* If a driver wishes to be notified about dock events, they can
* use this function to put a notifier block on the dock notifier list.
* this notifier call chain will be called after a dock event, but
* before hotplugging any new devices.
*/
int register_dock_notifier(struct notifier_block *nb)
{
if (!dock_station_count)
return -ENODEV;
return atomic_notifier_chain_register(&dock_notifier_list, nb);
}
EXPORT_SYMBOL_GPL(register_dock_notifier);
/**
* unregister_dock_notifier - remove yourself from the dock notifier list
* @nb: the callers notifier block
*/
void unregister_dock_notifier(struct notifier_block *nb)
{
if (!dock_station_count)
return;
atomic_notifier_chain_unregister(&dock_notifier_list, nb);
}
EXPORT_SYMBOL_GPL(unregister_dock_notifier);
/**
* register_hotplug_dock_device - register a hotplug function
* @handle: the handle of the device
* @ops: handlers to call after docking
* @context: device specific data
*
* If a driver would like to perform a hotplug operation after a dock
* event, they can register an acpi_notifiy_handler to be called by
* the dock driver after _DCK is executed.
*/
int
register_hotplug_dock_device(acpi_handle handle, const struct acpi_dock_ops *ops,
void *context)
{
struct dock_dependent_device *dd;
struct dock_station *dock_station;
int ret = -EINVAL;
if (!dock_station_count)
return -ENODEV;
/*
* make sure this handle is for a device dependent on the dock,
* this would include the dock station itself
*/
list_for_each_entry(dock_station, &dock_stations, sibling) {
/*
* An ATA bay can be in a dock and itself can be ejected
* separately, so there are two 'dock stations' which need the
* ops
*/
dd = find_dock_dependent_device(dock_station, handle);
if (dd) {
dd->ops = ops;
dd->context = context;
dock_add_hotplug_device(dock_station, dd);
ret = 0;
}
}
return ret;
}
EXPORT_SYMBOL_GPL(register_hotplug_dock_device);
/**
* unregister_hotplug_dock_device - remove yourself from the hotplug list
* @handle: the acpi handle of the device
*/
void unregister_hotplug_dock_device(acpi_handle handle)
{
struct dock_dependent_device *dd;
struct dock_station *dock_station;
if (!dock_station_count)
return;
list_for_each_entry(dock_station, &dock_stations, sibling) {
dd = find_dock_dependent_device(dock_station, handle);
if (dd)
dock_del_hotplug_device(dock_station, dd);
}
}
EXPORT_SYMBOL_GPL(unregister_hotplug_dock_device);
/**
* 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);
hotplug_dock_devices(ds, ACPI_NOTIFY_EJECT_REQUEST);
undock(ds);
dock_lock(ds, 0);
eject_dock(ds);
if (dock_present(ds)) {
acpi_handle_err(ds->handle, "Unable to undock!\n");
return -EBUSY;
}
complete_undock(ds);
return 0;
}
/**
* dock_notify - act upon an acpi dock notification
* @handle: the dock station handle
* @event: the acpi event
* @data: our driver data struct
*
* 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.
*/
static void dock_notify(acpi_handle handle, u32 event, void *data)
{
struct dock_station *ds = data;
struct acpi_device *tmp;
int surprise_removal = 0;
/*
* 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_bus_get_device(ds->handle,
&tmp)) {
begin_dock(ds);
dock(ds);
if (!dock_present(ds)) {
acpi_handle_err(handle, "Unable to dock!\n");
complete_dock(ds);
break;
}
atomic_notifier_call_chain(&dock_notifier_list,
event, NULL);
hotplug_dock_devices(ds, event);
complete_dock(ds);
dock_event(ds, event, DOCK_EVENT);
dock_lock(ds, 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;
default:
acpi_handle_err(handle, "Unknown dock event %d\n", event);
}
}
struct dock_data {
acpi_handle handle;
unsigned long event;
struct dock_station *ds;
};
static void acpi_dock_deferred_cb(void *context)
{
struct dock_data *data = context;
dock_notify(data->handle, data->event, data->ds);
kfree(data);
}
static int acpi_dock_notifier_call(struct notifier_block *this,
unsigned long event, void *data)
{
struct dock_station *dock_station;
acpi_handle handle = data;
if (event != ACPI_NOTIFY_BUS_CHECK && event != ACPI_NOTIFY_DEVICE_CHECK
&& event != ACPI_NOTIFY_EJECT_REQUEST)
return 0;
list_for_each_entry(dock_station, &dock_stations, sibling) {
if (dock_station->handle == handle) {
struct dock_data *dd;
dd = kmalloc(sizeof(*dd), GFP_KERNEL);
if (!dd)
return 0;
dd->handle = handle;
dd->event = event;
dd->ds = dock_station;
acpi_os_hotplug_execute(acpi_dock_deferred_cb, dd);
return 0 ;
}
}
return 0;
}
static struct notifier_block dock_acpi_notifier = {
.notifier_call = acpi_dock_notifier_call,
};
/**
* find_dock_devices - find devices on the dock station
* @handle: the handle of the device we are examining
* @lvl: unused
* @context: the dock station private data
* @rv: unused
*
* This function is called by acpi_walk_namespace. It will
* check to see if an object has an _EJD method. If it does, then it
* will see if it is dependent on the dock station.
*/
static acpi_status
find_dock_devices(acpi_handle handle, u32 lvl, void *context, void **rv)
{
acpi_status status;
acpi_handle tmp, parent;
struct dock_station *ds = context;
status = acpi_bus_get_ejd(handle, &tmp);
if (ACPI_FAILURE(status)) {
/* try the parent device as well */
status = acpi_get_parent(handle, &parent);
if (ACPI_FAILURE(status))
goto fdd_out;
/* see if parent is dependent on dock */
status = acpi_bus_get_ejd(parent, &tmp);
if (ACPI_FAILURE(status))
goto fdd_out;
}
if (tmp == ds->handle)
add_dock_dependent_device(ds, handle);
fdd_out:
return AE_OK;
}
/*
* show_docked - read method for "docked" file in sysfs
*/
static ssize_t show_docked(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct acpi_device *tmp;
struct dock_station *dock_station = dev->platform_data;
if (ACPI_SUCCESS(acpi_bus_get_device(dock_station->handle, &tmp)))
return snprintf(buf, PAGE_SIZE, "1\n");
return snprintf(buf, PAGE_SIZE, "0\n");
}
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;
begin_undock(dock_station);
ret = handle_eject_request(dock_station, ACPI_NOTIFY_EJECT_REQUEST);
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
};
/**
* dock_add - add a new dock station
* @handle: the dock station handle
*
* allocated and initialize a new dock station device. Find all devices
* that are on the dock station, and register for dock event notifications.
*/
static int __init dock_add(acpi_handle handle)
{
int ret, id;
struct dock_station ds, *dock_station;
struct platform_device *dd;
id = dock_station_count;
memset(&ds, 0, sizeof(ds));
dd = platform_device_register_data(NULL, "dock", id, &ds, sizeof(ds));
if (IS_ERR(dd))
return PTR_ERR(dd);
dock_station = dd->dev.platform_data;
dock_station->handle = handle;
dock_station->dock_device = dd;
dock_station->last_dock_time = jiffies - HZ;
mutex_init(&dock_station->hp_lock);
spin_lock_init(&dock_station->dd_lock);
INIT_LIST_HEAD(&dock_station->sibling);
INIT_LIST_HEAD(&dock_station->hotplug_devices);
ATOMIC_INIT_NOTIFIER_HEAD(&dock_notifier_list);
INIT_LIST_HEAD(&dock_station->dependent_devices);
/* we want the dock device to send uevents */
dev_set_uevent_suppress(&dd->dev, 0);
if (is_dock(handle))
dock_station->flags |= DOCK_IS_DOCK;
if (is_ata(handle))
dock_station->flags |= DOCK_IS_ATA;
if (is_battery(handle))
dock_station->flags |= DOCK_IS_BAT;
ret = sysfs_create_group(&dd->dev.kobj, &dock_attribute_group);
if (ret)
goto err_unregister;
/* Find dependent devices */
acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
ACPI_UINT32_MAX, find_dock_devices, NULL,
dock_station, NULL);
/* add the dock station as a device dependent on itself */
ret = add_dock_dependent_device(dock_station, handle);
if (ret)
goto err_rmgroup;
dock_station_count++;
list_add(&dock_station->sibling, &dock_stations);
return 0;
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);
return ret;
}
/**
* dock_remove - free up resources related to the dock station
*/
static int dock_remove(struct dock_station *ds)
{
struct dock_dependent_device *dd, *tmp;
struct platform_device *dock_device = ds->dock_device;
if (!dock_station_count)
return 0;
/* remove dependent devices */
list_for_each_entry_safe(dd, tmp, &ds->dependent_devices, list)
kfree(dd);
list_del(&ds->sibling);
/* cleanup sysfs */
sysfs_remove_group(&dock_device->dev.kobj, &dock_attribute_group);
platform_device_unregister(dock_device);
return 0;
}
/**
* find_dock_and_bay - look for dock stations and bays
* @handle: acpi handle of a device
* @lvl: unused
* @context: unused
* @rv: unused
*
* This is called by acpi_walk_namespace to look for dock stations and bays.
*/
static __init acpi_status
find_dock_and_bay(acpi_handle handle, u32 lvl, void *context, void **rv)
{
if (is_dock(handle) || is_ejectable_bay(handle))
dock_add(handle);
return AE_OK;
}
static int __init dock_init(void)
{
if (acpi_disabled)
return 0;
/* look for dock stations and bays */
acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
ACPI_UINT32_MAX, find_dock_and_bay, NULL, NULL, NULL);
if (!dock_station_count) {
pr_info(PREFIX "No dock devices found.\n");
return 0;
}
register_acpi_bus_notifier(&dock_acpi_notifier);
pr_info(PREFIX "%s: %d docks/bays found\n",
ACPI_DOCK_DRIVER_DESCRIPTION, dock_station_count);
return 0;
}
static void __exit dock_exit(void)
{
struct dock_station *tmp, *dock_station;
unregister_acpi_bus_notifier(&dock_acpi_notifier);
list_for_each_entry_safe(dock_station, tmp, &dock_stations, sibling)
dock_remove(dock_station);
}
/*
* Must be called before drivers of devices in dock, otherwise we can't know
* which devices are in a dock
*/
subsys_initcall(dock_init);
module_exit(dock_exit);